generations 2 - 2009

Generations A magazine published by ABB Marine. In this second issue of 2009, come aboard Oasis of the Seas, the world’s biggest cruise ship! We explore China, and discuss the finance crisis with Wang Jinlian of CANSI. Read how ferry operators cut fuel costs, how shore-power regulations are developing and much, much more!

A close-up look at semiconductors

The rules that frame our work are in constant change. This page looks at one change.

This time: Shore power.

This section shares some of the unique vocabulary on Russian and Norwegian ship bridges

News from the world of ABB Marine – production, R&D, projects, support.

News of innovations in ABB that may soon change your marine business too

We surveyed over 50 maritime professionals in Asia about shipbuilding and rules leadership.

Look closer and it gets more and more complex. Delve into the details of ContraRotating Azipod®.

feature content Generations Poll 01 Here & Now 02 House Rules 03

The common denominator for all of us is that we are problem solvers. Here, we see how ferry operators have used new technology to cut fuel costs.

Tech Porn 04 Slang 06 Power Provider 07 Microscope 08 Problem Solved 10

Some questions are common to all of us in the marine business. This article looks at the latest thinking on… training for demanding operations.

Professional Endeavour 16 Fieldbook 19 Market Survey 20 Q&A 26 Brains Trust 30 Perspectives 34

You probably like to read, but don’t have much time.

We pick out a few good titles for you. This time: Doing business in China.

We look at life in one country for marine professionals.

Let’s go to China!

Learn from experience.

We go one-on-one with a leader with an exclusive, in-depth interview. This issue: Wang Jinlian of the China Association for the National Shipbuilding Industry (CANSI)!

360° Customer 40 Just as it sounds, we look at a major customer from many different angles. We dive into Royal Caribbean Cruise Ltd.

Interviews with many people involved in designing the power systems for the world’s biggest cruise ship.

A dream team of engineers imagine futuristic answers to real problems. This time we streamline electric propulsion.

Examining ways to lower the likelihood of blackouts

Rethinking how to distribute electrical power around a ship

Semiconductor advances will lead to better power systems

What does a ship need to be ready for shore connection?

Shore power: good for the planet, but needing conversion

technical content 49 shore connection – 50-60Hz power conversion 53 shore connection – onboard installation 57 power semicondutors 64 innovative ship distribution systems 70 blackout prevention and recovery 78 deepwater piplayer 81 azipod xo 86 crp azipod 90 marine academy – SINGAPORE 95 voltage and frequency control Isochronous or speed drop control of diesel engines?

Educating a new generation of seafarers

Design considerations in the contra-rotating Azipod®

Innovations in the next generation Azipod®

Going to China to see crane vessels and dredgers

WRITERS Heikki Soljama Ji-Seung Yoo Joanne Jing Gu Johs Ensby Juha Koskela

Munaf Rahimo

Roar Nyheim

Ryan Skinner

Scott LaHart

Gery Yao

Lauri Tiainen

William (Bill) Wright

Rolf Taxt

Karl Morten Wiklund

Kai Levander

Jyri Jusslin

Anders Aasen

Harri Kulovaara

Kari Pihlajaniemi

Jarmo Orava

Vesa Juola

Marko Turunen

Antti Lehtelä

Arto Uuskallio

microscope

Marcus Martelin

David Bingui-Li

Anders Røed

Klaus Vänskä

Jennifer Varino

EDITORIAL Alf-Kåre Ådnanes

3600 profile

Jan Fredrik Hansen

Iulian Nistorch

ABB Marine editorial board: Heikki Soljama, Gery Yao, Alf-Kåre Ådnanes, Jyri Jusslin, Juha Koskela, Rune Lysebo, Anders Røed & Julia Cai ||| Managing Editors: Say – PR & Communications, www.say.biz (Daniel Barradas, Johs Ensby & Ryan Skinner) Design & Art Direction: Daniel Barradas Journalism, photography & illustration: See article by-lines ||| Uncredited photos: ABB image bank or shutterstock.com Printing: ColorMaster Norge

Eric Leong

David-BingHui Li

Andreas Hämmerli

Jan-Fredrik Hansen

power provider

Alf Kåre Ådnanes

Alexander Wardwell

perspectives Thomas Voelkel

house Rules

Sergey Shevchuk

Pål Nikolaysen

Brains Trust

Ross E. Berg

Arun Dev

problem solved

William YiLiang Huang

Evan E

Alf-Kåre Ådnanes

Klaus Vanska

Wang Jinlian Meng Guang Li

Kiyoshi Takaoka

q&a

slang

professional endeavour

This Generation

Otto

Daniel Barradas

DESIGN Kathryn Rathke

PHOTO

João António

Yuichi Adachi

Rune Lysebo Shutterstock

Juoni Saaristo

Milla Johansson

Martin Schiefer

Marcus Martelin ABB image bank

Lutz Thurm Wang Zhihui

Karen Liow Wang Hua

Jyri Jusslin Tomi Veikonheimo

Tobias Wikström

Julia Cai

Every issue of Generations is a massive collaborative effort. Here are the sources (above) and the production team (below) that made this issue happen.

ILLUSTRATION

Generations magazine ||| Issue 2-2009 ||| All rights reserved ||| Generations is published twice annually by ABB Marine, a business unit of ABB ||| The opinions expressed in this magazine are those of the authors or persons interviewed and do not necessarily reflect the views of the editors or ABB Marine ||| This magazine is not a retail product ||| For subscription information, go to www.abb.com/marine

How will the recession end?

It already has, some might say. And, yes, the recession has technically ended in many major markets. But it doesn’t feel that way, and the maritime industry, in particular, is still hurting. We asked a few colleagues and customers back in spring to describe how they saw the recession ending. Here are their answers.

Wing Hau Chia Sales Engineer, ABB Marine Singapore

Since the credit crunch, the way businesses operate has changed fundamentally. Many businesses used to leverage heavily on debtbased financing to operate, which put them in a difficult situation during the credit crunch.

This forced them to restructure their business towards a more stable and reliable growth model.

This restructuring is a good start, as companies refocus on their business strategies in the current economic situation.

Sadly, unemployment has hit the job market.

This exerts a downward pressure on wages, personal income and consumer spending, which reduces demand and corporate earnings. If unemployment persists, it may pose a risk to the recovery.

Many countries have introduced monetary and fiscal stimulus policies to soften the economic impact of the financial crisis.

However, this may lead to higher inflation, with colossal sums of money introduced into the financial system. The risk will grow if the excess liquidity of credit is not reduced in time to prevent a jump in commodities prices.

In sum, this recession may end with high unemployment and slower growth, due to soft demand for goods and services. In addition, the risk of inflation will also play a crucial role in determining the speed of the economic recovery.

Ronald Jansen Regional Technical Advisor Power Generation and Distribution, ABB Marine Miramar, Florida, USA

From an engineer’s perspective, which may be different than that of an economist, I believe that the recession will end favorably as consumer fears subside.

There is a silver lining in all that has happened. Numerous incentives from companies and stimulus packages from the government have been offered to consumers, especially for fuel efficient vehicles and home appliances.

Advantageous purchases are the key to helping the economy’s upturn. Those who have the ability to make energy efficient changes in their cars and/or home appliances will benefit in the long run.

For example, we recently replaced our air conditioning unit, and our electrical bill dropped by 25 per cent a month. Plus we will receive up to 30 per cent of the cost in a government stimulus savings tax credit. A relative small investment today will save us big money in the future because energy prices will continue to rise.

Together we can work on a brighter future.

J. Martin Kennerley Senior Electrical Manager, Carnival Cruise Lines

I believe the financial institutions and banks of the world hold the key to the end of the economic recession.

Yes! The same people who contributed greatly in accelerating the recession during 2008, with various bad investments, will ultimately be the ones who provide the confidence to return into the market place.

Credit and investment are fundamental supports to businesses large and small, without which it is almost impossible to grow and prosper.

The recent credit crunch is starting to relax and, provided loans and investments (at reasonable rates) are given based on sound experience, this will stimulate growth.

Consumers ultimately need confidence to spend money; this is how the recession will end.

I hope at the end of 2010 we will have emerged from these uncertain times and can look back at the lessons to be learned.

Kimmo Kokkila Lead Engineer, Technical Sales Support, ABB Marine Helsinki, Finland

The recession will end by unwinding excessive debt in the West. This will lead to a plunge in demand, destruction of capacity and bankruptcies, globally. Whether this unwinding takes a year or a decade remains hazy, but eventually demand will pick up to meet the remaining capacity.

But let’s go further and ask how we can play our part in ending it.

We can take a lesson from the Great Depression. In addition to ingenuity in business or technology, winning companies generally shared one common factor: they continued to invest in marketing to promote their brand to customers. Also today, we can apply the same: what is the value of having the best solution if the customer does not see it?

To play our part, we must have the best deal and ensure our customers know it.

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Generations Poll

What is Asia’s take on elementary shipping issues?

We surveyed over 50 different shipping professionals from Korea, Singapore, Japan, India and China.

What is the primary mission of the shipping industry?

After China, which do you think is the world’s fastest growing shipbuilder?

India Brazil Vietnam Russia Philippines UAE Malaysia Indonesia

What energy source will create a revolution in shipping in the 21st Century?

Natural gas Batteries Hydrogen Sun Biofuel Nuclear power Wind Tides Clean coal

Which national government is the best at managing the shipping industry?

Singapore Japan Korea China UK Germany USA India

generations poll

Move goods safely Serve global businesses Move goods cheaply Maintain world trade Ensure supply of resources Ensure global production of goods Keep the world’s shipping fleet in optimal shape Serve cargo owners

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Here & Now ABB won a contract to deliver electrical power, thruster drive and drilling drive systems to two new drillships to be built at Samsung Heavy Industries for Schahin and Etesco. ABB will provide generators, highvoltage distribution systems and electric drilling and thruster drive systems.

The world’s biggest cruise vessel, Oasis of the Seas, completed its sea trials, and was delivered to RCCL in October. Her sister ship – Allure of the Seas – will be launched in November. ABB has delivered a power plant and three 20 MW Azipod® propulsion systems to each vessel.

japan ABB won a contract to supply electric propulsion systems, including transformers, variable-speed drives and electric motors, to four supply ships under construction at Universal Shipbuilding Corporation for Sanco Shipping.

norway In October 2009 ABB undertook acceptance testing of the ABB Diesel Generator Monitoring System (DGMS). The DGMS compares the performance of each generator set to its expected behaviour and to other running units, and warns of faults early enough for controllers to perform a controlled shutdown. Benefits include greater availability, lower risk of blackout and improved data logging compared to traditional systems.

south korea

here & now

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china ABB has decided to establish a production line for its compact Azipod® propulsion systems in Shanghai. Products from this factory will commence sales in the 1st quarter of 2010, with first deliveries scheduled for 1st half 2011.

Compact Azipod®

finland

singapore ABB has launched a new Drilling Drive Diagnostics system, an add-on component that logs critical drive system data for failure diagnostics and troubleshooting. Logged data can be either packed and e-mailed to ABB’s support team for fault diagnostics or analyzed by ABB via a secure Internet connection. norway ABB replicated the stators for the NEBB generators of the DSV Pelican, owned

by Subsea7, based on original drawings. The ship’s generators were originally supplied by NEBB, a popular but now defunct producer of electrical motors and generators, which was later integrated in ABB. This kind of service is highly specialised, unique and valuable, as Subsea7 could extend the lifetime of its vessel without making costly modifications to fit new generators. |||

house rules

Shore Juice?

Green-minded ports and cruise lines have pioneered the use of shore power for moored ships.

But ongoing work on policy, technology, cost and utility will determine how the practice spreads worldwide. Here’s a glimpse of the future.

Ryan Skinner ||| illustration: Otto

in 2001, princess cruises began using shore power in Juneau, Alaska, where legislators were moving early to protect air quality. It was a first for shipping companies. With this precedent, legislators elsewhere opened their eyes to shore power.

The IMO, the EU and state and local governments in the USA and Europe are all moving on ship emissions regulations, and many of them are including shore-based power in their rules. Why? It allows ships to shut down auxiliary engines burning dirty heavy fuel oil.

Detractors point out that it is expensive, and may just move the emissions problem to land.

Both shore power’s critics and allies recognize the need to establish standards for shore power, and rules that make sense for ports, shippers and the public. Standards will be in place soon. Rules are further off.

“We aimed for a single technical standard for all ships, like in the aviation industry,” says Thomas Voelkel of ABB in Germany. “But the power needs and capacities of ships differ so much, we found it simplest to establish a few, similar standards instead.”

Voelkel led an IEC working group in Germany to create a standard for shore power, and later contributed to the work of a worldwide group that has put forward a common set of specifications in the IEC, IEEE and ISO. If the proposed standards are ratified as expected, there will be a global standard by year’s end.

According to Voelkel, the biggest challenge was not ship-side or shore-side, but the connecclosest to simplest

tion from ship to shore. Eventually, they settled on one connection for container ships, another for cruise and a third for all other ships. “Container, passenger and tanker terminals are all unique anyway,” he said. coming to a regime near you Shore power is available in ports from Long Beach and Seattle to Gothenburg, Sweden and Antwerp, Belgium. Governments can’t force shore power on anyone yet; for that, it’s too expensive.

Yet, shore power is making it into the law books in the EU and in California. A 2005 EU directive set very low sulphur caps to ship fuel while in EU ports starting in 2010, with an exception for ships hooked up to shore power.

Given the cost of such fuel, the EU hopes to entice ships to choose shore power.

California, on the other hand, has set a schedule requiring increasing use of shore power from 2014 to 2020, with an option for shipowners to reduce NOX and particulate emissions by other means, if they can and wish.

IMO MARPOL rules also look set to spur shore power, with very tough fuel standards coming into place over the next ten years.

Meanwhile, states worldwide are funding studies and infrastructure to help more ships get their power from shore. |||

house rules – SHORE JUICE?

writer:

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Tech porn

Potent little devices They’re in personal computers, telephones, TV remote controls, and coffee brewers, but few recognise them or what they can do. Semiconductor devices have an amazing potential to improve our world. writer:

tech porn – semiconductors

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Alf Kåre Ådnanes

semiconductor devices are digital electrical switches. They can be open or closed, allowing electrical current to pass, or stopping it or allowing it to pass in one direction only. And they can switch current flow thousands of times in a second. They can thereby control power with extreme accuracy and precision, with efficiency around 98-99 per cent.

They are not the solution to the world’s energy needs, but they help us to utilize energy in an environmentally friendly way.

Different kinds of semiconductor devices A diode is a kind of semiconductor that conducts current in one direction only, like a hatch in plumbing.

Symbol: Plumbing analogy:

Forward conducting Reverse blocking

A thyristor, like a diode, conducts current in one direction only. But, in addition, a thyristor can stop conducting in both directions. The opening time of the flow direction can be controlled.

Symbol: Plumbing analogy:

Forward, OFF blocking Forward, ON conducting Reverse blocking

Transistors and gate turn-off thyristors (GTO) can stop the flow of current altogether, and then – via a signal – allow current to pass in either direction. Another signal can close a GTO. Forward, OFF blocking

Symbol: Plumbing analogy:

Forward, ON conducting Reverse freewheeling

No thicker than a few millimeters nor wider than a centimeter or two, a silicon wafer like this can conduct thousands of Amperes or block kilovolts – all controlled by electric signals

Generations data sheet Name: Semiconducting device Measurements: Millimeters wide and ultra-flat Favorite activities: Saving energy Favorite place: In a cold, tight spot Guilty pleasures: turn-ons and turn-offs, 1000s of times a second Turn-ons: Electric stimulation.

Turn-offs: Milliseconds after turn-ons

tech porn – semiconductors

Most embarrassing moment: Confusing a turn-on for a turn-off.

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SLANG

Hear the producer of uncensored speech Much Norwegian and Russian terminology for items on or around a ship’s bridge stem from their origin, or their likeness to animals. So don’t be surprised to hear about an ape’s fist, a wind-mill or a samovar on these bridges. writer:

Ryan Skinner ||| illustration: João António

Wind-mill [ВeТpЯК - Vetryak] : Russian for weather station, this is literally translated as wind-mill or wind-drive, as older weather stations had blades to measure windspeed.

slang

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Bed-bug squeezer [КЛОПОДВ - Klopodav] : Russian term for the mechanical morse key. Literally translated, this word means “bed-bug squeezer”, as the original machine was ideal for smashing bed-bugs.

Sputnik [СПУТНИК - Sputnik]: Russian term for the global positioning system (GPS), which uses satellites (descendents of sputnik) to report a ship’s coordinates.

Monkey island Norwegian term for the deck over the bridge. Why? Who knows, but the English use the same term.

Producer of uncensored speech

Donkey man

[MaТЮГaЛЬНИК - Matyugalnik] : This word means roughly “producer of uncensored speech” in Russian, and refers to the loudspeaker – occasionally manned by a foul-mouthed mate.

[Donkeymann] : Originally the stoker, this Norwegian term now refers to the mate responsible for clearing trash

Intestines [КИШКa - Kishka] : Russian for intestines, this word is used for a fire hose for obvious reasons.

Tractor [Tpaktop - Tractor] : On Russian bridges, this word is used to refer to the start and reverse console. Mates who came to the merchant fleet from Russia’s navy were accustomed to breaking ice like a tractor plows earth.

Ape’s fist [Apeneve] : This Norwegian term refers to the knob on the end of a heaving line, which – apparently – resembles a monkey’s fist.

Dog’s shift [Hundevakt] : Norwegians give this unflattering name to the unpopular shift on the bridge from midnight until 4 A.M.

Power provider ABB is a global leader in power and automation technologies. New ways to create and deliver power in other industries may soon impact the marine market. Here’s some of those innovations…

All new ABB standard and industrial drives from the beginning of 2009 will include a built-in calculator that measures how much energy the drive saves, the value in local currency and the reduction in carbon emissions.

ABB’s variable speed drives were designed to conserve energy compared to conventional methods of fan and pump control. These drives have documented reduced energy consumption by 30 to 50 per cent, and as much as 80 per cent. Now the energy efficiency calculator makes those savings visible in terms of kilowatt-hours or megawatt-hours, and dollars, euro, RMB or any other currency, and tons of carbon.

opc unified architecture ABB contributed to creating a new standard for interconnectivity in state-of-the-art industrial automation technology called OPC Unified Architecture (OPC UA). This will enable different products from different vendors to communicate on a common interface. The first ABB product supporting OPC UA is already on the market.

The new standard was developed by over 30 major automation vendors over five years, and is published as IEC 62541. It employs web services technology, making it platform-independent and capable of more applications.

Further, OPC UA allows seamless integration with Manufacturing Execution Systems (MES) and Enterprise Resource Planning (ERP) systems.

innovating robots welds A new piece of software from ABB allows robot operators to perfect the welding procedure from their desks.

The welding simulator, called VirtualArc, allows an operator to run several test simulations of a weld before programming the robot.

The software uses a sophisticated simulator that incorporates information on the equipment available, such as the welding device and the power supply, and application data, such as the materials to be used, the plate thickness, joint configuration, etc.

This is the first simulator allowing per-weld analysis, and allows optimisation of the robot in a few minutes – a fraction of the time used on a conventional test. irrigation control solution A wireless irrigation solution from ABB has reduced energy consumption by 30 per cent, improved agricultural productivity by 25 per cent and saved enough water to meet the annual needs of 2.3 million people, in an arid region of Spain.

The system uses remote terminal units and the GPRS telecommunications network to provide a highly flexible and low-cost remote-controlled solution. 7,900 RTUs control 10,700 sets of water valves and counters. Powered by solar panels, these communicate wirelessly with a central control centre. |||

power provider

energy efficiency calculator

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Better manoeuvrability Azipod turning angles are +/- 135 degrees normally, with another option being a free, 360-degree rotation.

The better manoeuvrability of the CRP Azipod® system eliminates the need for a stern thruster.

microscope – CRP azipod

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Steering As long as the Azipod propeller is within the slipstream of the main propeller, then efficiency gains are maximised. The aim is to get 7-to 10-degree turning without going outside of the slipstream. This steering angle range covers autopilot operation.

Efficiency With forward propeller rotation energy utilised in the aft propeller, CRP Azipod® takes rotational losses and recovers them in a closed system. In fact, the higher loaded the propeller is – i.e. the more rotational losses there are in the slipstream – the more valuable the CRP Azipod is due to larger efficiency gains picked up by slipstream recovery. The system also benefits from a single skeg design, where the advantage of better hull efficiency is utilised.

Microscope

CRP Azipod®: High power and speed in a small diameter Scott LaHart

Featuring a steerable Azipod unit mounted immediatedly behind – and rotating in the opposite direction of – the shaft-driven standard propeller, the CRP Azipod® is an extremely resourceful system for high-power, high-speed vessels with propeller diameter limitations. Indeed, the contrarotation of the independent propulsion systems makes for great efficiency improvements.

After the crp (contra-rotating propulsion) was installed for the first time on the ShinNihonkai Ferry RoPax fast ferries in Japan in 2004, the benefits were immediate. They included a 20% savings in fuel consumption, 15% more transportation capacity and 25% faster vehicle turnaround.

For a more technical discussion of the Azipod® CRP technology, see the article in Chapter B, page 86!

Control arrangements The CRP Azipod control system automatically maintains the optimum power split window between the main propeller and Azipod propeller. This tends to be around a 70% load ratio on the main propeller and 30% load ratio on the aft (Azipod). A lower percentage ratio for the aft would not allow it to pick up the efficiency gains from the slipstream that it is intended for. CRP’s manual mode, however, allows the captain to change main and aft propeller power splits in order to assist with manoeuvring.

Shaftline drive Since podded drives have better overall efficiency, a power plant with a lower nominal output can be chosen without raising utilisation. This means that auxiliary appliances can have lower power ratings as well – thereby leading to lower power consumption on the vessel.

Propeller differences In order for CRP Azipod to work properly, there must be variations between the main and Azipod propellers. The Azipod propeller diameter is smaller than the main propeller to prevent main propeller tip vortex cavitation from hitting the Azipod propeller in autopilot steering angles.

There are also differences in the number of blades on the two propellers in order to avoid blade resonance.

Tugboats needed no longer While conventional twin-screw ferries need tugboat assistance in wind speeds over 13 m/s, ferries equipped with the CRP Azipod® system can manoeuvre without tug assistance in wind conditions of up to 18 m/s.

Less power (& fuel) needed – and it’s redundant, too When the concepts were studied for the ShinNihonkai Ferry RoPax fast ferries, it was found that a twin screw propeller system would require 59 MW of power, while the CRP Azipod® system reduced power needs to 52 MW. Fuel consumption reduced accordingly – from approximately 220 tonnes/day to 190 tonnes/day.

Another major added CRP Azipod® benefit is redundancy. If something were to happen with the main propulsion system, then the Azipod® aft propeller would still provide enough power and manoeuvrability to transport the vessel where it needs to go – albeit at lower speeds (from 32 knots to around 20).

microscope – CRP azipod

writer:

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problem solved

Problem: reduce fuel consumption!

Anyone owning, operating or chartering a ship shares the problem. Two different ferry operators, with completely different operations, each solved it by exploring and investing in new propulsion technology. The result is fuel savings ranging from 10 to 20 per cent. writer:

problem solverd – reducing fuel consumption

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Ryan Skinner ||| maps: Daniel Barradas ||| photos: Shin Nihonkai Ferry Co., Ltd. (SNF) and Sinorail Bohai Train Ferry Co.

when shin nihonkai ferry co., ltd. (snf), an operator of high speed coastal ferries in Japan, was engineering fuel efficient designs for its latest two newbuildings early in 2003, the bunker fuel price was over JPY25,000 per kiloliter. Six months later, it was almost JPY30,000. And by 2008, it was over JPY90,000. This year, it subsided again to around JPY50,000. The motives behind SNF’s desire to cut fuel consumption were compounded by the actual development in fuel prices.

It is a common challenge, but one particularly close to the heart of ferry operators. Ferries market their services to very price-sensitive consumers, their high-speed port-to-port operations are energy intensive and, in some cases, they are forced to use a grade of marine fuel

one or several steps cleaner and more expensive than conventional heavy fuel oils.

This issue of Generations studies how two ferry operators solved this problem, if only partially, by choosing new propulsion systems that would meet their unique operating profiles and cut fuel costs. Both have been a success, and each have expressed an interest in building on their experiences with newbuildings with even lower fuel consumption.

Conventional service 3 vessels x 20 knots Otaru

Maizuru

background The first company to open a ferry route in the Sea of Japan, in 1970, Shin Nihonkai Ferries (SNF) was also the first to operate large high-speed ferries when it took delivery of Suzuran and Suisen (max. speed of 31 knots) in 1995.

Early this decade, the company set out to revolutionize its service between Maizuru and Otaru, which – at 573 nautical miles in distance – required three ferries operating at 20 knots in order to maintain a daily service. SNF wanted to serve the route with only two ferries.

In order to do this, however, the company would need to run larger ferries at a service speed of 30.5 knots over the choppy Sea of

Fast ferry CRP Azipod service

Vessel type

• Faster service • Reduced fuel consumption

Maizuru

the solution In meetings with ABB, SNF immediately expressed interest in the CRP (contra-rotating propeller) Azipod technology.

The technology had never been exploited on a commercial vessel, but ABB could document that CRP Azipod improved fuel efficiency by 15 per cent. SNF contacted a shipyard, Mitsubishi Heavy Industries, and together they began designing a high-speed RoPax ferry using CRP Azipod.

CRP Azipod’s advantages for high-speed, high-power applications, such as large >>>

Shin Nihonkai direct comparison

2 vessels x 30 knots • Increased cargo volume

Japan. Based upon its experiences with Suzuran and Suisen, SNF concluded that fuel costs made a similar solution for this route prohibitively expensive. In order to launch such a service, SNF would need to find a radical, but realistic, way to reduce fuel consumption.

problem solverd – reducing fuel consumption

Case study #1: Shin Nihonkai ferries’ Hamanasu and Akashia

Otaru

Fuel oil consumption southward

Fuel oil consumption northward

Conventional diesel-shaft line fast ferry

125,000 L

122,000 L

CRP Azipod-powered diesel electric fast ferry

110,000 L

102,000 L

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problem solverd – reducing fuel consumption

container ships, LNG carriers or RoPax ferries, were intuitive. The design builds on a single skeg, but replaces the rudder with a fully-rotating Azipod unit pulling directly behind the main propeller. The effect is an improved cavitation profile and an enhanced hull form.

ABB Marine had been testing these principles since 2000, together with SINTEF Marintek in Norway, Samsung Heavy Industries, Aker Finnyards and Wärtsilä, and finally in the Mitsubishi model basin. Computational fluid dynamics testing and models demonstrated the performance of CRP Azipod, and ABB Marine had marketed it to likely users without getting a first order.

success. First of all, Hamanasu clocked an astounding top speed of 32.04 knots. Even better, the ferry’s fuel oil consumption beat SNF’s own prognoses.

Then, in 2003 SNF ordered two ferries using the CRP Azipod technology from ABB Marine at Mitsubishi Heavy Industries, believing the ferry design could achieve SNF’s goal of a 10 per cent reduction in fuel consumption. In signing the deal, SNF President Yasuo Iritani said it was acting upon its successful studies of the concept: “The ships are somewhat more expensive than conventional ferries but the operational savings are big enough for us to recover the initial expense.”

In May of the following year, SNF took delivery of Hamanasu and eagerly sought to start sea trials. These were an overwhelming

Hamanasu demonstrated a reduction in fuel oil consumption that exceeded 20 per cent, even when operating at a slightly higher speed (approximately one knot). This performance confirmed the results from Mitsubishi’s test basin in Nagasaki.

A subsequent test showed an even more remarkable result. In 2006, Akashia was put into a service together with Suisen, allowing a direct ship-to-ship comparison. Over 6 days, Akashia averaged over 20 per cent less fuel oil consumption in a northward leg against the current, and going south with the current.

Finally, a test in May 2009 moderated these

the results Depending on the study and the situation, the two new CRP ships (Hamanasu and Akashia) use anywhere from 15 to 25 per cent less fuel compared to the somewhat older, conventional high-speed ferries Suzuran and Suisen.

Initial tests could not directly compare fuel performance, as a parallel test with a CRP Azipod-driven ship and a conventional ship was impossible. Nevertheless, the earliest trials of

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the impact It is difficult to estimate how much of SNF’s operating costs stem from bunker fuel prices alone, as these are constantly fluctuating, but industry experience suggests that it can easily exceed 50 per cent. SNF pays a particularly steep price, as it is required to use a relatively clean standard of fuel (180cSt HFO)

by Japanese authorities.

Kiyoshi Takaoka, SNF’s director for ship’s operation, was able to estimate the fuel cost savings per ship per year to as much as USD 3 million, given today’s fuel prices. With fuel prices like those in 2008, the savings are comparatively greater.

Ironically, the improved fuel consumption has been achieved while improving other commercial aspects of the ferries, not hurting them.

Thanks to the more efficient design made possible by a single skeg and the CRP Azipod’s flexible diesel-electric layout, Hamanasu and Akashia have 15 per cent more cargo volume.

On average, the ships operate faster too, and can maintain cruising speeds in wave heights that force Suzuran and Suisen to slow down.

Lastly, the electrical system allows power used for refrigeration on one leg to feed the propulsion system on the return.

SNF’s success with the CRP Azipod system has not gone unnoticed. Japanese Mitsui O.S.K. Lines, Ltd. (MOL), one of the world’s leading car carrier companies, recently launched a concept ship that can reduce carbon emissions by 50 per cent, in many cases by increasing fuel efficiency. The design incorporates a contra-rotating propeller system, which it credits for increasing efficiency by 17 per cent.

Case study #2: Sinorail Bohai Train Ferry Co. Train ferries 1, 2 & 3 background In 2003, Chinese authorities gave the green light to an investment project designed to provide a train ferry service across the Yellow Sea from Yantai to Dalian. This service would cut the travel distance between these two key economic centres by 1800 kilometres and tie them closer to Shanghai and the Yangtze River Delta region to the south.

Sinorail Bohai Train Ferry Company, the company created to manage this route, brought a flexible approach to the operating environment that its future ships would face. First of all, the ships could operate at the relatively slow cruising speed of 16-18 knots. Secondly, the ferries would need high manoeuvrability and reliability, given the regularity of traffic, the rough and icy conditions of Bohai Bay and the great amount of time spent in or near the terminal compared to cruising time. Finally, the company needed to keep costs low enough to make the voyage attractive compared to >>> the circuitous route around Bohai Bay.

C H INA

Dalian

B O H AI B AY

Yantai

problem solverd – reducing fuel consumption

results, but still showed a reduction in fuel oil consumption near 15 per cent. In this instance, the two CRP Azipod-powered ferries were compared directly with Suzuran and Suisen on another route, from Tsuruga to Tomakomai and back. Here Hamanasu and Akashia consumed 12 per cent less fuel with the current, and 18 per cent less against the current.

13

After a long and intensive period of study and co-operation with the Shanghai Merchant Ship Design & Research Institute and the shipyard, Tianjin Xingang Shipyard, Sinorail Bohai chose to equip its RoPax ferries with a diesel electric propulsion system powering two Compact Azipod units.

Sinorail Bohai’s technical director Meng Guang Li described how the company settled on the Compact Azipod solution. First of all, the company weighed a traditional mechanical propulsion arrangement against a diesel-electric arrangement.

are most efficient when they run at their rated speed. Running at lower speeds cause higher fuel consumption and potential mechanical damage. With the diesel-electric system, we can run the engines at rated speed and adjust the number of generators according to the load,” said Guang Li. Sinorail Bohai chose to equip its first three rail ferries with the Compact Azipods in 2007.

The solution included full electrical propulsion systems, including generators, switchboards, transformers, drives and two 4.088 MW compact azipods per vessel.

“The diesel electric system had an advantage because we do not need the space-consuming engine and shaft line arrangement.

Thus we could optimize our engine room placement and get more cargo onboard,” said Guang Li. “The diesel-electric system is smaller. We could use a high/medium-speed diesel engine, which is much cheaper than a low-speed one. And the diesel electric system’s mechanical weight is as much as 30 per cent less.”

The diesel electric system’s ability to perform efficiently at low speeds was another vital point for Sinorail Bohai. “Diesel engines

the results The Compact Azipods made it possible to optimize the ferries’ hull form. Also due to the more efficient running of engines and the reduced need for power to manoeuvre in port, Sinorail Bohai knew it would see reduced fuel costs from its rail ferries. Initially, the question was how much.

“We have compared the train ferries with other ferries of a similar size that are running on the same route with conventional propulsion. Based on these comparisons, we can estimate that fuel consumption for the Compact Azipod ferries is at least 20 per cent lower,” said Guang Li. In fact, one direct comparison

the solution

problem solverd – reducing fuel consumption

14

Ship’s tonnage

Cargo tonnage

Service speed

Service power

Oil cost per ton-mile

Conventional diesel-shaft line train ferry

16000

11138

16.5

70%

4.218

Compact Azipod-powered diesel electric train ferry

24975

17548

16

85%

3.310

between a diesel engine ferry operating as efficiently as possible (at 70 per cent load levels) and the Compact Azipod ferry still shows an advantage of 20 to 30 per cent.

Today ABB Marine is undertaking a more complete survey of Sinorail Bohai’s operations, and particularly savings in terms of fuel consumption.

In terms of sheer numbers, the impact Compact Azipod propulsion has had on Sinorail Bohai’s operations is tangible and impressive. Consider that the company estimates fuel expense at approximately 50 per cent of the ship’s overall operating costs. Thus, a 20 per cent reduction in fuel costs is roughly equivalent to a reduction of 10 per cent to the company’s overall operating costs. the impact

“We have three train ferries equipped with Compact Azipod. Each ferry can save roughly four tons of fuel oil, which equates to an annual saving of approximately

problem solverd – reducing fuel consumption

Vessel type

RMB 15 million to our bottom line.”

Meng Guang Li, Technical Director, Sinorail Bohai

In addition to the reduction in fuel consumption, Sinorail Bohai has felt a number of other advantages to Compact Azipod propulsion. Specifically, the ship’s manoeuvrability is significantly enhanced, as its turning radius is small and it can move breadthwise. This, in turn, has lead to lower expenses for tugs, and better performance in heavy weather. The ship can approach port without a tug even in force 8 winds.

Further, because the Compact Azipod’s propellers can adapt to a load change, they are less liable to breaking when they strike ice, than in a traditional engine and shaft line arrangement. Lastly, noise and vibration are reduced in Sinorail Bohai’s newest train ferries, as the propeller and the engine driving it are not attached to one another.

“We have three train ferries equipped with Compact Azipod. Each ferry can save roughly four tons of fuel oil, which equates to an annual saving of approximately RMB 15 million to our bottom line,” said Guang Li. “With other fuel-saving efforts, such as low cruising speed and fuel additives, we can come to the market with a very competitive offer.”

He confirms that the company plans to continue to equip its ships with Compact Azipod propulsion systems, and explains that basic design work has already begun on one such newbuilding.

Sinorail Bohai’s train ferry service from Dalian to Yantai and back have the potential of shortening transit of 18 million tons of cargo and 7 million people by 1800 kilometres. The value of this saved distance in terms of time, emissions and money is enabling increased growth in some of China’s most powerful economic hubs. |||

15

Professional Endeavour

Combining training and operations The need for training is a reality that must coexist with the running of a company. Is combining rigorous training and demanding operations difficult? In a word, yes. And, as an area that impacts the work of every professional, training’s importance is critical. In this article, we will touch upon the challenge of time and scheduling in addition to the type of training, its integration into the workplace, employee retention and the need for flexibility. To bring you the latest thinking, we connected with an expert in Singapore and two practitioners, one in the United States and one in Denmark.. professional endeavour – training and operations

16

writer:

Jennifer Varino ||| illustration: Otto

being in a time crunch is a common challenge in today’s world. Dr. Arun Dev, Director of Newcastle University Marine International (NUMI) in Singapore, says, “People involved in operations are always short of time – no matter how much time is given. I have even heard that managers come in boiler suits and fall asleep during training.” This tiredness could be accounted for by the fact that managerial positions arguably require the most training.

And, Dr. Dev stresses that the training they really need is soft skills, such as team building. “The human side is so very important and we can’t lose sight of that. We want to avoid situations where, for example, colleagues sitting next to each other email instead of having direct contact.”

All agree that a focus on the volume of employees who have been trained is not a useful metric. While it may look good for quality assurance or marketing, the number of hours or persons in the classroom does not establish competency. Training must be effective – or it risks being a waste of valuable time. So how can we be assured that the skills learned are successfully integrated into the job?

Pride International has a very practical solution. As one of the world’s largest offshore drilling companies, the company trains many, many employees. Its standard is to require effective training

an employee who has completed training to demonstrate his or her competency for a supervisor, who then rates the employees performance.

Pride’s Training Manager for the Gulf of Mexico, Ross E. Berg elaborates, “We require a vast quantity of training – in particular because of our work with new builds. Hands-on time in the field is a critical component – for example, you have to examine the equipment, see it installed, understand it.” Berg estimates that approximately 50 percent of Pride’s training occurs on the job and every position requires not only classroom training, but also on-the-job training.

Dr. Dev adds that he sees communications skills as critical to the effective integration of training – or indeed for being successful at work in the first place. He says, “The most important skill to have on the first day of any job is communication. He stresses the importance of English skills for non-native speakers and

Singapore spurs training on To cut corners on training during challenging economic times is short-term thinking. The Skills Programme for Upgrading and Resilience (SPUR) initiative is a two-year enhanced financial support scheme that strives to help Singaporean companies manage the economic downturn and invest in skills for the recovery. It brings together a full range of skills upgrading programs, covering over 800 courses for companies and workers to tap into until December 2010.

Ross Berg’s tips for combining training and operations: 1. Have a plan 2. Be flexible 3. Set priorities

professional endeavour – training and operations

4. Schedule longer shift lengths (for those in the field)

17

business communication skills for those who are already secure in the language. “Those who do not speak or write English well may produce good work but what about their future?”

Training requires a large investment from a company, so employee retention – which makes sense in any industry – really pays off. Pride makes a concerted effort to support all employees, from entry level to top management. Berg says, “At Pride, we use a building blocks approach. It is designed to not only accomplish the tasks of a particular position, but to move you to the next. Higher level positions receive more advanced training, but the quantity and quality do not change.”

He continues, “We want people to move up from the inside. Our goal is to hire at the lowest level and then keep the employees so that we can fill all positions internally. We provide leadership training to all of our employees so that everybody knows their input is a vital part of our success.” keeping your employees

Even though it means that additional training is needed, Berg explains that the impact of new equipment is positive. “There are lots of people who want to work on the newest and best equipment and that is what we’ve got now.

So we attract top individuals who want to keep their work interesting. And with newbuilds, our plan is that our people are fully competent on day one when we start for our customers.” flexibility is key Would simply increasing the number of employees ease the logistical challenges surrounding the combination of training and operations? “No,” says Berg, explaining that the limited bed space on the rig allows only a certain number on it at any one time. He suggests instead adapting a 28-dayson/28-days-off schedule. The longer time off the rig allows for more flexibility to fit in training and also respects the employee’s private time. “If you are working a 14/14 schedule, you will lose 50 percent of your family time if I schedule you for a one-week class. But if you

Five-Star Rig Training Late last year when Maersk Drilling prepared a team made up of around 90 specialists from 14 nationalities to start up a highly advanced, deepwater development semi-submersible rig, the training task was entirely too large and complex to handle at company offices. Instead, they rented an entire hotel in Denmark and carried it out there – for a full two months at a time.

The Hotel Grand Park session wasn’t a one-off. Maersk Drilling had already carried out a similar assembly the previous year for its first deepwater semi-submersible rig in a professional endeavour – training and operations

18

are working 28/28, I have only taken 25 percent of that time.” In addition, developmental training, though important, can be flexible enough to fit into the schedule after required training dates are already established.

“Maintaining a membership with your respective professional institute or society is an excellent way to stay on top of continuing professional development (CPD),” states Dr. Dev. Such affiliation provides a great opportunity for professional status, recognition and networking within the relevant professional community itself – in addition to seminars, courses, meetings, discussion groups, etc. He adds,

Dr. Dev encourages us to think out of the box— or classroom: 1. Integrate training into the workplace or it is useless 2. Create a knowledge center, an in-house “university” 3. Be open to others – you may at times learn more from fellow trainees in your class than from the instructor 4. Maintain membership in your professional society – these organizations are a great resource for continuing professional development.

series of three. They were so pleased with the results that they repeated the procedure for the second vessel in the series, turning to this comprehensive training model due to the sophisticated nature of the rigs.

During the first two months of the training period, all of the specialists that needed expert knowledge on drilling equipment, subsea equipment, dynamic positioning and so on carried out training sessions at vendor locations themselves.

Afterwards, when everyone assembled at the hotel, three classrooms were put into place – one for drilling, one for marine operations, and a third for maintenance, along with a drilling and crane simulator.

“I believe companies should support this through a subsidy for employees as many hesitate to pay the annual membership fees.”

In stark contrast, the developing world, Dr. Dev points out, struggles with the absence of training good enough to produce an appropriately skilled workforce. Poor families in countries such as Bangladesh pay fees to small local shipyards or steel fabrication companies because there are not sufficient training facilities. These workers then move overseas and work mainly for subcontractors who do not normally cover any long-term training costs for foreign employees. |||

Fieldbook

Read, then do business in China Western businesses have flooded into China since the early 1990s, and more will come.

Here’s a selection of their accumulated wisdom.

doing business in china

fieldbook - business in china

China CEO: Voices of experience from 20 international business leaders – Juan Antonio Fernandez and Laurie Underwood A professor of business at IESE in Spain and a journalist team up to bring insights from British Petroleum, General Motors, Philips and Unilever, among others, on how to “crack” the Chinese market.

Chinese business negotiating style – Tony Fang A classic. Fang began as a naval architect and negotiator for Chinese shipyards, but his path led him to Sweden where he studied management. This gives an insider’s tips to closing deals in China.

Doing business in China: How to profit in the world’s fastest growing market – Ted Plafker The Economist’s Beijing correspondent describes the opportunity in China, along with the pitfalls, while killing some myths (such as, he says, that spoken Chinese is difficult to learn) business etiquette in china

The lowdown: Business etiquette in China – Florian Loloum “…will give you practical tips on how to navigate your way through a business trip to China, and on how to behave and how NOT to behave in both business and business socialising situations..”

The art of the deal in China: A practical guide to business etiquette and the 36 martial strategies employed by Chinese businessmen – Laurence J. Brahm Extract: “‘Yes’ is always the first word in a negotiation, not the last, in China. Too often when foreign investors and businessmen hear the word ‘yes’ in China, they assume the deal is done.”

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Web-sites and Blogs Doing Business in China: The World Bank www.doingbusiness.org/china The Federation of International Trade Associations www.china.fita.org The Economist www.economist.com/countries/china China Business Services www.chinabusinessservices.com/blog Asia Biz Blog www.asiabizblog.com China-based news analysis www.allroadsleadtochina.com Law and business in China www.experiencenotlogic.com

Market survey

Building giants in China China’s rise as a shipbuilding nation has been driven by a government’s determination, plentiful labour, rapid modernization and thousands of aspiring entrepreneurs. Today China can look around the world at shipbuilding peers. But how will the current crisis impact Chinese aspirations? Here we present a quick market survey of major shipbuilding regions, yards and ports, as well as some vital maritime statistics, and a quick look at China’s response to the market downturn. writer:

Ryan Skinner ||| photos: Shutterstock ||| map: Daniel Barradas

Five major shipyards Dalian Shipyard – Dalian Shipbuilding Industry Corporation

market survey - china

20

(DSIC) (China Shipbuilding Industry Corporation – CSIC) Based in China’s northern city of Dalian, this shipyard has set impressive growth targets: 6 million dwt by 2010, 8 million tons by 2015 and 10 million dwt by 2020. It specialises in several designs, including a 300,000 dwt VLCC, a 4,668 TEU container ship, a 230,000 dwt FPSO, a 28,000 multi-purpose vessel, a 44,000 dwt product tanker and a 12,300 dwt Ro-Ro vessel.

Hudong – Hudong-Zhonghua Shipbuilding (Group) Co., Ltd. (China Shipbuilding Group Corporation – CSSC) A Shanghai-based shipyard, Hudong is situated along both sides for Huangpo River, and covers 1.35 km2 and 2 km of coastline.

This yard is the result of a merger between Hudong and Zhongua shipyards, and builds merchant and naval ships. Merchant tonnage includes large container ships, LPG carriers, chemical carriers, RoRo ships, FPSO, crude oil tankers and passenger ships.

Jiangnan (China Shipbuilding Group Corporation – CSSC) Located in the Puxi area of Shanghai, this is a relatively new shipyard scheduled to start operation in 2010, with an area of 5.6 km2 and 3700 meters of coastline. The yard’s annual capacity will be 4.5 million dwt, with capability of building a variety of naval and merchant vessels, and marine structures. This is one of six pilot businesses chosen by China’s government as centres of technology innovation.

NACKS – Nantong COSCO KHI Ship Engineering Co., Ltd. A joint-venture between COSCO and Kawasaki Heavy, NACKS is approximately one hour’s drive northwest of Shanghai. Main build types include 150-300,000 dwt oil tankers, Ro-Ro vessels, 10,000 TEU container ships and 300,000 dwt ore carriers.This yard sprang up after a total investment of RMB 3.6 billion by its two owners.

Waigaoqiao – Shanghai Waigaoqiao Shipyard (China Shipbuilding Group Corporation – CSSC) This shipyard covers 5 km2 on Changxing Island near Shanghai. Its shipbuilding capacity totals roughly 7 million dwt, including capesize and panamax bulk carriers, VLCC oil tankers, FPSOs and semisubmersible drilling rigs.

The top ten ports in China, by tonnage Shanghai – Feeding hinterlands of the Yangtze River Delta and Yangtze River Valley Shenzen – Feeds the economic hinterland for Hong Kong trade with the mainland

Qingdao – A natural deepwater port, Qingdao moved 300 million tons of cargo

Ningbo – Located on the rich coastal province of Zhejiang and features large, modern terminals

Guangzhou – The largest comprehensive port in South China, this port is a vital hub for the entire region Tianjing – The closest major port to Beijing, Tianjing features the largest man-made port in China.

Xiamen – An important deep-water port that can handle 6th generation large container vessels.

Dalian – The most northern ice-free port in China, and the largest multi-purpose port in NE China.

Lianyun – The largest port in China to import alumina and export wheat and veneer. Aims to reach 100 million tons of cargo.

Zhongshan – In Guangzhou and close to Macau and Hong Kong, this port serves a rich hinterland for manufacturing.

Ports Shanghai

2

Shenzen

3

Qingdao

4

Ningbo

5

Guangzhon

6

Tianjing

7

Xiamen

8

Dalian

9

Lianyun

10

Zhongshan

Shipbuilding and shipping in China

LIAONING

8

Shipyards A

NACKS

B

Waigaoqiao

C

Hudong

D

Jiangnan

E

Dalian

The number of shipyards scattered along China’s 14,500 kilometer long coastline reaches into the thousands. They are clumped around three major shipbuilding areas, and have varying degrees of privatisation. Here’s a look at some of those hubs:

E

6 TIANJIN

3

Bohai Bay area The northernmost shipbuilding hub, Bohai Bay boasts a number of major ports and shipping cities, including Dalian, Yantai, Tianjin and Qingdao.

SHANDONG

JIANGSU 9 S H A N G H AI A

4

ZHEJIANG

FUJIAN 7

1 B C

D

Province

Proportion of Chinese shipbuilding, by ton

Liaoning

17.48%

Tianjin

0.36%

Shandong

6.07%

Yangtze River Delta This hub encompasses a number of provinces where the Yangtze River meets the sea. The Yangtze River Delta includes the Shanghai region, and other major centres like Ningbo and Zhenjiang.

Province

Proportion of Chinese shipbuilding, by ton

Jiangsu

34.52%

Shanghai

20.49%

Zhejiang

9.97%

Pearl Delta GUANGDONG 10

5

2

The southernmost shipbuilding hub, this region features many smaller yards, scattered around a cluster called the Longxue Area.

Province

Proportion of Chinese shipbuilding, by ton

Fujian

1.81%

Guangdong

5.83%

market survey - china

1

21

Average starting monthly salary for engineer – RMB 1500 – 3500 (USD 220 – 500)

Average cost of a standard Dell PC in Shanghai – RMB 3-7000 (USD 440 – 1000)

market survey – china

22

Leading recruitment channels for Chinese shipping

Leading organisations in the Chinese maritime sector

China Ship News www.chinashipnews.com.cn

China Society of Naval Architects and Marine Engineers (CSNAME) www.csname.org.cn Established in 1943, this society that focuses on technical communication within the maritime industry. CSNAME currently has approximately 30,000 individual members, 800 company members and 18 branch societies.

China Shipping www.shipbuilding.com.cn/hr.php Shipping online www.shippingonline.cn Shipfriends.net www.shipfriends.net/b/jobs.php http://ship.jdjob88.com

Leading maritime exhibitions Marintec China www.marintecchina.com 1 – 4, December, 2009

Shanghai International Boat Show www.boatshowchina.com 8 – 11, April, 2010

Shiport China www.shiport.com.cn 26 – 28, October, 2010

INMEX China www.maritimeshows.com/china 8 – 10, December, 2010

Major maritime media titles in China China Ship News www.chinashipnews.com.cn Technology and Economy Information of Shipbuilding Industry Shipbuilding of China Shipping Engineering www.cbgc.com.cn China Ship Survey http://cs.ccs.org.cn/

China Association for the National Shipbuilding Industry (CANSI) www.cansi.org.cn Established in 1995 as a non-profit organisation to unite Chinese shipbuilding disciplines, CANSI includes shipbuilders, ship repair yards, marine equipment manufacturers, R&D institutes, professional schools and universities. It currently numbers over 530 enterprise members.

Maritime Safety Administration of the People’s Republic of China (MSA) www.msa.gov.cn China’s Maritime Safety Administration operates 20 regional authorities, including 97 local branches. It implements policy, supervises safety, prevents pollution and administers inspections and controls, in the maritime and fluvial areas.

China Classification Society (CCS) www.ccs.org.cn China’s Classification Society dates from 1956, and is the only organisation of its kind in China. It seeks to provide independent, impartial and integral classification and statutory services to ships and offshore installations.

China Shipowners’ Association (CSA) www.csoa.cn China’s Shipowners’ Association was founded in 1993, and has the same responsibilities as its peers across the globe, in acting as a voice for the industry, protecting members’ rights, contributing to the international dialogue around shipping, etc.

Cost of ship steel at major Chinese shipyards Material (board deck, middle thickness)

Size (mm)

Producer

Price (RMB)

A387 Grade 91 Class 2

20x1500x6000

Fushun Steel

13,000

A387 Grade 22 Class 1

12x1500x6000

Wugang Steel

13,400

A387 Grade 22 Class 1

6x1500x6000

Wugang Steel

13,500

A387 Grade 11 Class 3

19x1500x6000

Fushun Steel

13,000

A36

12x1500x6000

Jiyuan Steel

5,320

A36

6x1500x6000

Jiyuan Steel

5,720

A387 Grade 11

20x1500x6000

Fushun Steel

13,200

380Cst (USD/ton)

180Cst (USD/ton)

LDO (USD/ton)

Dalian

443-444

450-451

630-635

Qinghuangdao

443-444

457-458

639-644

457-458

695-700

457-458

630-635

457-458

632-637

Port name

Tianjin Qingdao

440-441

Lianyungang Shanghai

451-452

460-461

640-645

Guangzhou

441-442

448-449

637-642

Zhanjiang

446-447

454-455

637-642

Ningbo

452-453

460-461

650-655

Fangcheng

443-444

457-458

637-642

Container shipping costs, as of July 2009 (all prices in USD) Port

Average price, from Shanghai

Specific shippers’ prices, from Shanghai

Average price, to Shanghai

Rotterdam

1235

1000 (MISC)

700

Long Beach

1550

1075 (CSCL)

900

Dubai

785

975 (UASC)

385

Singapore

350

225 (YML)

450

market survey – china

Bunker prices at major Chinese ports, as of July 2009

23

Chinese shipbuilding in crisis the chinese government has great ambitions for the country’s shipbuilding industry.

So far, these have proceeded according to plan. The financial crisis, however, challenges the entire industry, and Chinese authorities are moving quickly to respond, and preserve the country’s rate of growth. there are three pillars to the shipbuilding crisis and recovery in today’s China:

market survey – china

24

overcapacity China’s Ministry of Industry and Information Technology, which monitors the development of the country’s shipbuilding industry, warned earlier this year that overcapacity in the country exceeded 16 million deadweight tonnes. China’s volume shipbuilding market had expanded rapidly during the boom years, but – after the financial crisis struck – it was overextended.

As an example, an article in Shanghai Business Daily described the quandary of CSSC and COSCO, which had invested heavily in new shipbuilding bases in the Yangtze Delta and Zhu Jiang delta over the past two years. These efficient production sites will suffer from painful under-utilisation if the market does not improve.

By 2012 at the latest, the problem of overcapacity will become increasingly acute,

Huangpu river, Shanghai

“Our government has determined to eliminate part of the production capacity, and accelerate their regrouping. [...] Shipbuilding is likely to continue to decline throughout 2009 and in the first half of 2010.”

– Chief of China’s Ministry of Industry and Information Technology Shipbuilding Department (Source: Shanghai Business Daily)

as many yards run completely dry of work.

For the time being, Chinese authorities have placed a 3-year hiatus on new capacity projects to help this situation.

A problem that will haunt Chinese shipbuilders for some time is ships that were built before orders (in effect, to stay ahead of demand, when capacity was at a premium). Today many such ships are rusting and tying up capital along China’s coastline.

Even if China’s orderbook is strong, it is vulnerable. First and foremost, Chinese yards risk a string of cancellations. Figures vary, but a report by CSERC gave the number of cancellations per May 2009 at 125 ships.

Another challenge is delays. According to one newspaper article, as many as 1/3 of newbuilding orders at China’s largest shipyards have been subject to a request to delay delivery, as shipowners struggle to allocate the necessary funds. cancellations

stimulus Overcapacity and cancellations will each be eased by an improvement in conditions for ship buyers, and improved financing. China’s Shipbuilding Stimulus Package addresses both:

China’s shipbuilding stimulus package – main points 1. Encourage financial institutions to increase credit funds for shipowners 2. Extend the term of financial support for transocean vessels sold to domestic owners to year 2012 3. Work out relevant plans for discarding or refitting obsolete ships, and scrap single-hull tankers 4. Terminate shipyard and slipway extensions for three years 5. Start projects to support R&D in high-tech and novel ship types, ocean engineering projects and affiliated equipment

General Manager of China State Shipbuilding Corporation

Chairman of China Association of the National Shipbuilding Industry

market survey – china

USD 2 billion

Zhang Guangqin

Unknown

51

President of China Shipping (Group) Company

79

Germany

Li Shaode

Turkey

Director, Department of Equipment Industry, Ministry of Industry and Information Technology of People’s Republic of China

3.23 million dwt

Zhang Xiangmu

Unknown

125

Tan Zuojun

220

PRC

President of China Classification Society

Korea

Li Kejun

Value or volume of cancellations

Director of China Society of Naval Architects and Marine Engineers

Newbuildings cancelled

Huang Pingtao

Country

Chairman of China CSSC Holdings Limited

(Source: CSERC)

Chen Xiaojin

Cancellations among major shipbuilding nations – Dec. 2007 to May 2009

General Manager of China Shipbuilding Industry Corporation

Lastly, Chinese yards that have been contracted by other shipyards, in Korea or elsewhere, to supply extra capacity now find these contracts drying up. The contracting shipyard, suffering its own slow-down, seeks to employ its own extra manpower.

Li Changyin

– Zhang Guangqin, CANSI Chairman

President of China Ocean Shipping (Group) Company

even 200 billion is not enough.”

Wei Jiafu

has approved a quota of 20 billion; in my view,

Leaders in the Chinese shipping world

“China’s shipbuilding industry investment fund

25

q & a – wang Jilian

26

Q&A

Generations is happy to present this exclusive interview with Wang Jinlian, General Secretary of the China Association for the National Shipbuilding Industry (CANSI). He describes the scope of the crisis facing China’s shipbuilders and discusses how his organisation is advising government and business to tackle it. As head of CANSI and with a strong industry background, Jinlian is in a perfect position to talk strategy. writers:

Wang Hua and Wang Zhihui ||| photo: Shutterstock ||| illustration: Kathryn Rathke

What are the ties between the global economy, marine shipping and shipbuilding?

These three are very closely linked. The decline in the global economy has resulted in a decrease in international trade, which directly affects the marine shipping market. In 2009, demand for global shipping fell sharply overall, but investment in global shipping capabilities for the same period actually increased, resulting in an even faster decline in the marine shipping market and a considerable drop in the cost of shipping. This slump in the marine shipping market ultimately affected the shipbuilding market and caused a considerable drop in orders for new ships worldwide.

This is in contrast to a large upswing in the shipbuilding production capacity over the past few years. In sum, the shipbuilding market faces some serious changes. The global economy is still in the process of recovering and so the marine shipping and shipbuilding

markets will remain at a low point for some time. My view on overall development is not entirely optimistic.

In terms of management of global shipbuilding, what areas are in urgent need of change?

The global shipping industry is an organic whole. Both competition and co-operation exist between shipbuilding countries. We should deepen communication and work together to face problems in the market. The development of the shipbuilding industry is linked to the development of other industries. As a major shipbuilding country, China drives not only other industries here in China, but also development of related industries in Europe.

The “China element” is becoming a driving force in world economic development. This is why we should all work together to strengthen co-operation and push the development >>> of the global shipbuilding industry.

q & a – wang Jilian

Wang Jinlian 27

q & a – wang Jilian

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What is the situation facing China’s shipbuilding industry today?

China’s shipbuilding industry is in a very precarious situation and faces a number of crises. There are four major issues to address: fewer orders, difficulties in delivery, financing and low profit. From January to August of this year, Chinese ship makers received 1.098 million DWT in orders for new ships, down 82 per cent from the same period last year – a result of an overabundance of shipping capability in the marine shipping market. This has resulted in increased delays in starting work and delivering new ships. The price for new ships has also fallen up to 20-30 per cent overall, with the price for some ship types falling over 50 per cent. Products offered by China’s shipbuilders are also too similar, resulting in an increasingly competitive market. In addition to this, the implementation of new standards and specifications are testing China’s shipbuilders even more.

How should China’s shipbuilding industry deal with the current crisis?

First, it should fully understand the situation. The shipbuilding industry has yet to recover and the market will remain at a low

Huangpu river, Shanghai harbour

point for some time. They need to prepare for this. Second, ship producers have to work on improving from the inside by increasing efficiency. Dealing with this crisis has to start from inside the company. Third, shipbuilders and manufacturers of related products have to support each other, coordinating development to make it through these difficult times. Fourth, an overall reworking of the industry structure should be carried out, not only in the area of production capability, but also in terms of product offerings and services. Shipbuilders should also keep up with changes in the market, strengthening contact between shipowners.

Will new environmental standards be a barrier to the development of China’s shipbuilding industry?

The International Maritime Organization (IMO) has recently become increasingly focused on environmental protection and has released a series of new standards and specifications, including the phasing out of single hull tankers, new coating standards and others.

These are all in the interest of environmental protection and are a big test for China’s shipbuilding industry. As these new standards and

What are the goals of China’s shipbuilding industry over the next 5-10 years?

According to the Plan for Ship Industry Reworking and Stimulation, China’s total shipbuilding production capacity should reach 50 million DWT by 2011, with installation of domestically produced ship products on the three major ship types reaching 65 per cent. This plan also estimates that by 2015 China will work to become the world’s most important shipbuilding country.

How has CANSI been able to achieve and maintain such a high position in the industry?

The ship industry today in China is very complex with state-owned companies, private companies, joint-ventures and wholly-owned foreign companies existing together. This creates a tough environment for coordination.

This, along with the effects from the financial crisis, means that the number of problems that need to be solved in the industry has increased.

CANSI must act as a bridge between government and business, adapting to current development trends and enhancing its management role in the industry.

CANSI has made a lot of valuable contributions over the years. Which of these makes you most proud?

There are three areas that I think we can be proud of. First is our ability to actively relate the requirements of business to the government. Second is our proactive participation in planning and policy work related to the shipbuilding industry. Last is our ability to quickly provide recommendations and opinions on the operation of China’s ship industry.

What is your view on the application of electric propulsion technology in ships?

Electric propulsion technology is the future.

In April of this year, I was lucky enough to visit ABB. Their advanced management and production techniques left a deep impression on me.

I’m confident that electric propulsion technology will be used widely in ships in the future.

If you could do anything you wanted right now, what would it be?

After being in the ship industry for so many years, I still feel that ship-related industries (ship technology suppliers) in China have yet to catch up to the shipbuilding industry. China has been using licensed trade practices for some time now. ABB has many producers in China and we have included ABB in the scope of domestic production. However, domestic production of ship-related products is still quite low in China. What I would really like to do is increase domestic production of China’s ship-related products by increasing independent innovation.

Outside of work, what other interests do you have?

I like to play cards, Chinese chess and find a better way of thinking about my work. |||

Wang Jinlian Born in October 1945, he graduated from the Beijing Institute of Aviation in 1969 with a BA in automation control and is a senior engineer. He worked as a technician, technology team leader and general motor production chief at the Hubei Yichang Diesel Ship Engine Factory. He also worked as a vice department head and then department head for planning at the China State Shipbuilding Corporation (CSSC), later becoming chief engineer for related equipment, bureau chief for the international section and ultimately director of development planning. He has also served on the board of directors of the Shanghai Waigaoqiao Shipbuilding Co., Ltd. and Hudong Heavy Machinery Co., Ltd. He held the position of director at the CSSC Economic Research Centre and chief engineer at the Guangzhou Zhongchuan Nanshalongxue Construction Development Co., Ltd. He is currently the General Secretary of the China Association of the National Shipbuilding Industry (CANSI).

q & a – wang Jilian

specifications come into effect, China needs to step up research and adopt measures to deal with these changes.

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brains trust

How to reduce the number of components in an electrical propulsion system?

In each issue of Generations, we launch a thought experiment. A small group of ABB’s marine business unit creative engineers, a writer and an illustrator combine their diverse skills to present ideas about how the future might be.

What new technologies might emerge to solve intractable problems facing us today? The second ever meeting of the “Brains Trust” took place in Shanghai and sought to answer the question: How can you reduce the number of components in an electrical propulsion system? writer:

brains trust - reducing components

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Ryan Skinner ||| photos: Daniel Barradas ||| illustration: Otto

every engineer should be familiar with Rube Goldberg. This American eccentric gained notoriety for his inscrutable machine inventions.

Consider the “self-operating napkin”: A diner raises a spoon to his mouth, which pulls a string that launches a cracker. The cracker attracts a parrot, which flies up. The parrot’s perch then tilts and spills seeds into a cup that then weighs down a cigarette lighter, and so on and so forth until a napkin wipes the diner’s chin.

Goldberg’s absurd machines put engineering on its head. It turns one simple action into countless steps. In this issue of Generations, the brains trust endeavoured to un-Goldberg an electrical propulsion system. If such a system could be compared to a series of steps (power production, conversion, distribution and application), what can be done to reduce the steps?

In late April in Shanghai, a team of engineers in ABB’s marine business unit met to study how an electric propulsion system could theoretically be pared down to fewer elements.

The benefits of such a reduction stem from reduced cost, reduced maintenance and increased efficiency (every time electricity is converted, losses mount). the challenge The brains trust workshop’s leader, Alf Kåre Ådnanes, sketched out the fundamental challenge of reducing components in such a system. Simply speaking, each component in an electrical system has a vital func-

tion. The generator turns mechanical power into electrical power. Transformers allow the electrical power to be distributed efficiently.

Switchboards direct the electrical power to where it is needed. If you take away any element, the system fails.

Thus, in order to make any progress, the brains trust would need to propose unconventional systems. The challenge was then to reconsider what was going into the system, what was coming out of the system or what the shipowner expected from the system. The inventor of the Post-It note, for example, had to abandon the value of a simple piece of paper (a note) and a piece of tape in order to realise the value of combining them.

After an afternoon of headscratching and intense discussions, the group settled on two different answers to the question.

The first answer sidesteps much of the technical aspects of the question. In effect, it reduces the number of electrical components requiring investment by the owner and maintenance by the ship’s crew to zero. This model establishes a new commercial model for supplying electrical power systems. The owner pays for the thrust provided by the system. The system’s provider can thus optimize the system in terms of the ratio of cost to thrust.

The second answer rethinks the fundamentals of a shipboard electrical grid by replacthe solutions

pay-as-you-go Pay-as-you-go’s opportunity lies in how an electrical system is optimized.

Today electrical systems are designed to provide a constant level of power at the same voltage and frequency, to both the ship’s thrust and its auxiliary power needs (hotel and control).

Effectively, this results in a reliable and easy source of energy – dumb electricity.

“There is considerable room for improvement in terms of how electricity is controlled and distributed, so that the amount of thrust is optimized. Thus, given a fixed amount of electrical production, in megawatts, we could offer an electrical management system that produces the most thrust in any condition,” said one brains trust member.

The electrical distribution system could be described as an Electrical Power Compatibility Layer, or EPCL. Such an EPCL would convert a given amount of mechanical energy into electrical energy at the highest possible efficiency.

It would be this torque and energy that forms the owner’s bill to the supplier, and not the cost of buying all of the elements in the production plant. The EPCL would be defined by the system integrator, and provided by the supplier of the generating equipment.

The advantage to a shipowner would be that it pays only for what it wants – electrical power and propulsion thrust. Additionally, it buys only the electrical production, in terms of engines, boilers and/or motors, and propulsion equipment, such as shaft-lines, propellors, Azipods® or thrusters. All of the components in between are conflated into a single system, the EPCL. Even if it is possible and beneficial, such a

The team Alf-Kåre Ådnanes Working from Singapore, Ådnanes leads research and development work in ABB Marine.

Klaus Vanska With experience in Asia and Europe, Vanska has some experience translating complex technical issues to readily understandable concepts.

Evan E E is a project lead engineer in the engineering department of ABB Marine in Shanghai.

William Huang An electrical engineer in ABB Marine’s team in Shanghai, Huang helps Chinese shipyards implement electrical propulsion systems onboard newbuildings.

pay-as-you-go set-up faces one major challenge.

If the ship has substandard thrust, then the supplier loses revenue but the ship and its owners face much greater losses. In other words, the commercial risk associated with the ship’s operations would need to be reflected in the contract between supplier and owner, perhaps in the form of a strict performance guarantee.

brains trust - reducing components

ing the existing AC distribution systems with a DC distribution system. With a common DC distribution system, there would be fewer transformations and less AC distribution infrastructure. Another striking advantage of such a system is that different energy sources could be combined in a common network, opening up to solar power, batteries and other sources.

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Conventional power set-up Power is generated at fixed voltage and frequency, and then distributed as alternating current (AC) via a system of switchboards and distribution transformers to accommodate different electric consumers throughout the ship. This set-up allows designers to use common electrical equipment, but it forces the power to undergo numerous conversions.

Conventional power generation

brains trust - reducing components

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power generation

distribution

Optimized power set-up Power that is developed as direct current (DC) is distributed as direct current, and passes to the propulsion system and auxiliary with fewer conversions. In this set-up, the main consumer (propulsion, which accounts for at least 70 to 80 per cent of all power consumption) is prioritised, and the entire power system is made simpler and more efficient.

power generation

transformer

propulsion

propulsion

transformer

transformer

propulsion

auxiliary

Matrix power set-up The matrix DC electric power plant turns the ship’s energy users (say the thrusters) into efficient parasites of the ship’s overall electrical generation. Thus, each thruster can be programmed to pull electricity from the producer that, for example, produces the power cheapest. In fact, the electricity generation could be arranged such that the different sources of energy go to those applications that can use them best, and cheapest.

Optimized power generation

power generation

power generation

distribution

The parasite (power-site) plant The matrix set-up’s capability of selecting the power that suits best is akin to a parasite, say a mosquito, that can find nourishment from many sources, but selects the one that fits its needs closest. Imagine a hungry mosquito with a huge brain that constantly calculates where it can get its meal cheapest, from solar power, batteries, wind, gas, diesel, biodiesel – whatever power sources are available to it. A matrix set-up enables this new paradigm of smart energy management onboard a ship.

propulsion

propulsion

propulsion

auxiliary

Matrix power generation

propulsion

power generation

propulsion

propulsion

power generation

auxiliary

the common grid dc distribution set-up

This technical set-up provided such inspiration within the brains trust group that one member wrote a technical paper describing it in detail.

This can be read in Chapter B of this magazine – see “Innovative Distribution Systems for Ships with Electric Propulsion” on page 64.

Here we provide only a layman’s version of the same story.

Today’s electrical power systems take AC (alternating current) power from the generators and transforms it for different voltage levels that are distributed throughout the ship.

Most of the power is converted to DC (direct current) within frequency converters, and then converted back to AC to power the motors that propel the ship. Other AC power is directed through switchboards to the ship’s electricity needs, powering everything from bridge equipment to deck cranes and crew television sets.

Further, today’s systems run at a consistent level of voltage and frequency within the EPCL. In terms of components, this has been a benefit, as they can be produced and controlled en masse according to accepted

industry standards. This benefit can be superseded by the development of better digital controllers and benefits of producers of energy that vary in terms of voltage and frequency.

In fact, a DC distribution system has many benefits, most of which relate to increased efficiency and flexibility. Without distributing and transforming AC for different voltage levels (except for auxiliary purposes), ships could forgo a significant amount of equipment. Further, a DC distribution system accommodates different energy sources more easily.

A so-called DC matrix system allows each electricity user to pull power from all of the electricity generators, instead of a typical setup where all of the power is pooled and then divided between the consumers. Such a system could easily tap the energy source that is most efficient at the moment, be it solar panels, batteries, diesel engines or otherwise. With reference to the work of last issue’s brains trust on the GREEN Cell shipping network (a conceptual system for powering ships without fossil fuels), this is particularly appropriate. |||

brains trust - reducing components

ABB Marine’s R&D head Alf-Kåre Ådnanes plots out the future of marine power systems, with the mighty skyline of Shanghai as backdrop.

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PERSPECTIVES

Bigger and better – in every way writer:

Scott LaHart ||| photos: Scott LaHart, Juoni Saaristo & RCCL

Perspectives 1. THE VALUE OF A LONG-TERM RELATIONSHIP

PERSPECTIVES – oasis of the seas power systems

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A history together helps lead to a shorthand – you know the other company’s values and way of working, and have already invested time in maximising processes. It also brings about continuity, which helps a project sail smoother. You can also look to other projects for evidence of what works well and what can be improved. In essence, you’re removing as many of the question marks as possible, easing your way to the final goal.

while the timing may not seem the most auspicious given the current state of the global economy, the grand scale and sheer innovation of Royal Caribbean’s Oasis of the Seas cruise vessel appears primed to trump any challenges placed before it.

Judging by the media coverage, interest in the 220,000-tonne vessel is unprecedented.

And with 40 percent more passenger space than any cruise ship that has come before it, and an entertainment package including diving and swimming show extravaganzas at the AquaTheater, a lush park containing sculptures and thousands of plants in the middle of the vessel and twenty-four restaurants, why not?

Such a large step up in size brings about added challenges in ship construction and operation – especially regarding the propulsion and power package, which includes a third turning Azipod® for the first time. Good thing then that Royal Caribbean, shipbuilder STX Europe, and power system provider ABB Marine have been working together on RCCL vessels since 1997. We’ve spoken with both ABB Marine and Royal Caribbean players on the front line of system development to get their viewpoints, as well as highlighted areas of note where views concur with one another, shedding light on some of the keys to project success.

2. IT TAKES TIME TO DO THE FIRST VESSEL IN A SERIES RIGHT Initial vessels in a series oftentimes call for new solutions.

And one small change one place can lead to a whole chain of changes across the board. It’s also fair to add that the larger the vessel is compared to previous series, the longer it will take as well. If all parties understand that such situations call for extra time, then the framework is in place for a long-term, forward-thinking result that will likely breed benefits for the remaining vessels in the series as well.

3. RESPONSIVENESS & TRUST In order to be a true partner, you need to be responsive when issues arise and take care of them. And problems will always arise. Instead of causing irreparable rifts between companies, if they are taken care of properly, problems can lead to a new level of trust between the two partners.

4. SOLVING MULTIPLE ISSUES WITH A SINGLE SOLUTION As vessels become larger, then equipment tends to become more advanced as well. It’s worth remembering here that this can be used to the vessel’s – and shipowner’s – advantage. If shipowners look beyond simple solutions for a single issue then they may pay more upfront. However, the benefits from these solutions may provide new possibilities – and new synergies – that far outweigh their alternatives.

relationship between abb marine, royal caribbean cruise lines

RCCL wanted us as part of the power package, based on their positive experiences with us from before. The main reason for this is the Azipods. When they decided to go in the Azipod direction for the Oasis class of vessels, then they automatically chose us.

STX, RCCL and ABB have been working together for a long time. We’ve cooperated with RCCL on at least 14 vessels, and we’ve worked on 10 vessels at STX’s Turku, Finland shipyard over the last 10 years. Many of the people we’re working with in Turku – such as system coordinator Heikki Laihinen – have been there since the beginning.

Vesa Juola

ABB systems lead engineer

Marko Turunen

ABB Azipod lead engineer

Jarmo Orava

ABB Marine project manager for Oasis project

abb marine deliveries to oasis of the seas We started working with hydrodynamic testing in 2004/2005, so ABB has been more or less involved with the Oasis of the Seas since the very beginning of vessel planning. There were several different alternatives tested here before agreeing upon the final system that’s set to be placed into use.

We delivered a great deal more on this vessel than on previous RCCL deliveries. In addition to the Oasis of the Seas’ propulsion and power system, we also delivered three turning Azipods – which is a first.

The main reason for the three turning Azipods on the Oasis of the Seas was the sheer size of the vessel. Adding the third Azipod was important for redundancy and increased manoeuvrability, which is essential when going into and coming out of certain ports – such as Miami. The biggest difference between having two turning Azipods on a vessel and three was the software designed to control them all: an entirely new software system had to be put into place because of this.

In addition to the pods, ABB has delivered the generators, main switchboards, frequency converters, transformers and remote control systems. It’s impossible to go into full specifics here – our “scope of supply” document for the vessel was a good 70-80 pages. abb marine presence at the shipyard during the project The vessel itself costs about €1.2 billion, and our share of the costs is approximately €35 million, so our overall contribution at that level might seem small. However, when you look at the contract sizes for the suppliers, we are one of the biggest. In fact, we’re always one of the biggest suppliers when it comes to cruise vessels.

PERSPECTIVES – oasis of the seas power systems

(rccl) & stx europe

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most critical & time-demanding aspects of

On the power plant side, we have six generators (three larger and three smaller) and a main switchboard divided into three parts. While this is a normal setup, this is a much larger switchboard than usual. Then we have five AC compressors, and four bow thrusters with starters. Additionally, we have some engine room transformers that provide the machinery with power, and substation transformers.

The most critical and demanding part for us is the propulsion systems – which consist of a total of six transformers, along with the converters and Azipods.

For sheer hours, though, the cabling may take up the most time. We are using a great deal more serial lines on the Oasis of the Seas than in previous vessels. There are 5000 kilometres of electric cables used on this vessel, and about 100,000 electric points. power system development

PERSPECTIVES – oasis of the seas power systems

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project challenges & getting past them

Planning for the Oasis of the Seas was difficult, because it was so different to any vessels that had been constructed before. The reference vessel, for example, had only two moving Azipods, so there were disparities from the very beginning.

As a brand-new type of vessel, there were a lot of “scope of supply” modifications on the Oasis of the Seas compared to many others. For example, all of the transformer details needed to be changed later. But part of the reason for the large number of changes is simply the result of a holistic system – one variation to the electrical system, for example, has ramifications for the equipment and the installations for a whole host of other areas of the vessel as well.

If we compare our scope of supply here to the Freedom class of RCCL vessels, it is

totally new. Since the Azipods have more power (20MW each), the cooling system is totally new. The Azipod steering system also had to be modified due to more challenging vessel manoevrability, and the drives and frequency converters are completely new types.

The power supply for the hull is completely different this time around as well.

We’ve been able to utilise our experience from RCCL cruise ships from before, but some things here were starting more or less from scratch. RCCL has shown understanding that this process takes time. They already knew that, no matter what the time calculations are on the first vessel, some of those hours will have to be transferred over to the second vessel as well. Now that everything is in place for the first vessel, it will make things easier for the remaining vessels in the series. ensuring good communication & cooperation

Project meetings from the beginning and commissioning meetings over the last year or so have tended to take place about every week. ABB does most of their work from Helsinki, but it’s close enough to Turku – just a few hours by car – to make meeting up and constant interaction fairly seamless.

STX is most active on the communication side – as this is the natural role of the shipyard. They called us and RCCL in for meetings on a regular basis, along with subcontractors such as Kongsberg Maritime. project trust There’s quite a good trust already in place from STX and RCCL due to previous projects that we’ve worked on together. While there have been some problems from time to time, we’ve managed to solve them without a great deal of fuss.

In fact, solving problems helps create an even greater level of trust.

It’s easy to get along with everything is running smoothly; it’s when there’s a problem that relationships really are brought to the test. If you’re able to make it out to the other side, then the relationship tends to be strengthened.

There were some challenges in the beginning, but we managed to solve them by flying in staff from Norway and a software engineer from Germany by helicopter. Carrying out work above and beyond the normal call of duty helps develop a layer of trust with the shipowner. what could have been done differently

Some preliminary designs needed to be scrapped, but this is part of the natural state of events when working on a brandnew class of vessel for the very first time – and especially one as large as this one.

While clients may want old, proven technology, this isn’t always possible with new vessels. recent changes in the market Deadlines are getting shorter and shorter, even though vessels are getting larger and larger. Part of the reason for this is that shipowners, by necessity, aren’t making decisions before they absolutely have to. As vessel financing becomes more difficult, several fronts need to be worked on simultaneously.

This means that, on the supplier side, you’re already late even at the beginning of a project.

Kari Pihlajaniemi

RCCL manager of newbuilding technology relationship between abb marine, royal caribbean cruise lines (rccl) & stx europe

While I’m not able to put any words in STX’s mouth, I believe that there’s a common interest from both sides to continue to work with ABB. Both have worked with ABB since around 1997, so there’s no sense in putting a new player in place without a reason. And we have no reason to do so.

The pod configuration on our cruise vessels was chosen a number of years back after considering a host of variables, and at this point there’s no reason to go back to a standard thruster setup. We wanted a reliable, well-proven system like we’d already experienced on many occasions with ABB – and one that gives us more flexibility to operate the vessel as well.

ABB Marine offers advanced equipment and design, and our cooperation with them has been excellent since day 1.

This relationship, along with reliability, life-cycle and affordability, are all key to our continued collaboration. We’re able to give them our input and feedback, and we get input back from them as well. It’s all part of a continuous dialogue.

PERSPECTIVES – oasis of the seas power systems

sea trial feedback

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PERSPECTIVES – oasis of the seas power systems

Anders Aasen, (left) RCCL’s Associate Vice President, Marine Technical Services and Jyri Jusslin, Senior Vice President, ABB Marine, in the control room aboard the Oasis of the Seas. rccl’s input on decision to utilise three

We came to a joint decision with STX that, instead of having two different Azipods, we could utilise three Azipods to maximise manoeuvrability. The three Azipod system increases the availability of the equipment – if one of the Azipods doesn’t work, then there are still two others that do. This adds desired redundancy. If one of the Azipods were to go out of service, we could more or less maintain the same vessel behaviour.

This system is more expensive, of course – the mounting block is more costly, and we have to add additional communications channels and controls. However, it’s worth it for us to gain added flexibility and redundancy – and this is the best way to do it. azipods on oasis of the seas

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process & considerations surrounding

The design process has three main players – the builder, the buyer/owner, and the maker. We always have to take into account the way the yard is planning, the design of the vessel, what sort power system development

of space they would have available, and so on. The maker we chose – ABB – both had to and wanted to be part of the process from the very beginning.

There were different considerations this time around due to the sheer size of the vessel. In addition to creating a larger vessel, we were also increasing the dedicated power output (from 14 MW units to 20 MW units) and had a different vessel design. All of these variables make for a number of challenges.

One of the biggest issues was the design configuration. It was done for the Solstice class before, but never before in Turku.

This included both the sizing, and type of converter/main drive unit. We also had a requirement from our management that while we are building two different classes with the same output, we should have a similar design in order to have spare pod units for both projects.

The 20-MW power output was the largest ever built by ABB with this design configuration, but everything went to plan and now we have a spare pod that will fit Oasis,

most critical aspects of power system

There were very few events during the trial that would raise any alarms, and no real problems with the pods. While there was a propulsion control failure when we left the Turku archipelago, we’re aware of why this took place. While in Germany we can run full propulsion from the start when we carry out sea trials, it isn’t possible to run at full propulsion in Turku before we’re farther out at sea.

While ABB had a single component failure, they flew specialists from Norway and Switzerland out by helicopter to the vessel, and they took care of the problem. We were very impressed with their responsiveness.

If you’re looking historically at our relationship with ABB, then it would have to be the generators. The same ones have been operational since 1999, and they’ve proven themselves from day 1.

We haven’t had any problems with them whatsoever – no major breakdowns and no major issues. As for the Azipods themselves, we haven’t had any unplanned dry dockings as a result of them since our very first vessel with the pod – the Voyager of the Seas – in October 1999.

Given our stock in the Azipod products, then our high priorities on the power system side relate to propulsion control, main switchboards and transformers. One of the most critical items on the Oasis now is the steering. ABB has now utilised Kongsberg Maritime to deliver the ship steering system, so our main concern was how to integrate ABB, Kongsberg and systems from the previous ship steering supplier.

All partners have room for improvement, and one area that stands out here is a better communications structure. Communications should be organised in such a way that a third party could come into the room and ask where we are now on Oasis and get the information back in a structured manner that would be accessible to all parties.

sea trial feedback The first sea trial met all of our expectations. Our chairman was visiting when we were sailing full speed ahead, 20 MW on each pod, and we didn’t notice anything out of the ordinary. It was very smooth sailing.

recent changes in the market The economic situation is the same for shipowners, shipbuilders and equipment suppliers alike, and I feel that it’s even more important during these times to have a solid cooperation platform. |||

development

what could have been done differently

In the future we will improve the integration process for the various partners involved.

This includes bringing in some of the subsuppliers – such as Kongsberg Maritime – at a much earlier stage. While ABB, RCCL and Kongsberg were doing their parts on time, the integrated knowledge that Kongsberg’s input, for example, matched ours, was lacking. the

importance

of

communication

PERSPECTIVES – oasis of the seas power systems

Solstice and Radiance class vessels. It was a great exercise from a company point of view.

Given that vessels have a life of about 30 years, life-cycle costs will always be one of the main drivers – much more so than just the initial installation costs. As the Azipod configuration has already proven to be more efficient, this is another important consideration.

It took two years to finalise the design and approval process. While this was quite a bit of time, it was time well spent.

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360° PROFILE

Evolution, not revolution As the world’s largest cruise ship, RCCL’s Oasis of the Seas represents a quantum leap for the industry.

But a closer look at the development, design and construction of this titan tells us a lot about the company and its history of innovation. writer:

360o profile – RCCL

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Alexander Wardwell ||| photos: Juoni Saaristo & RCCL

try, if you can, to forget about how big it is.

Not easy, when you consider that RCCL’s latest cruise ship, Oasis of the Seas, is 360 meters long and 47 meters abeam, providing enough space for 6,300 passengers. Or that it stands 65 meters above the waterline, measures 225,000 GRT and displaces 100,000 tons of water, making it the largest cruise ship ever constructed. By far.

To put it another way, if you stood the vessel upright bow-to-stern, it would dwarf New York’s Chrysler Building.

And for the moment, anyway, let’s try to ignore how much fun it would be for you and your family to take a cruise aboard the Oasis of the Seas.

Try not to imagine yourself enjoying the twostory loft suites, the climbing wall, solarium, miniature golf, a zip line, swimming pools, a water park for kids, the basketball court, spa and fitness centre, ice skating rink, twin outdoor Flowrider surf simulators, outdoor waterthemed amphitheatre, the traditional working carousel, and the dozens of shops, restaurants, and bars – including one which is mounted on hydraulics, so it can travel between decks. Oasis even has its own open-air park, which stretches almost the length of the vessel, which will support 12,000 individual plants, flowers and trees.

Instead, let’s look at Oasis of the Seas from another perspective. That is, Oasis of the Seas is certainly large and equipped to deliver a truly unique passenger experience, but the vessel tells us as much about Royal Caribbean works as it does about cutting-edge shipbuilding. >>>

“We did not build the largest cruise ship in the world to set a record.

Oasis of the Seas is large for one reason – to enable us to enrich the passenger experience.”

Harri Kulovaara, Executive Vice President, Maritime (RCCL)

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360o profile – rccl

>>> In many ways, the story of Oasis of the Seas is also a story about RCCL’s values and enduring spirit of innovation. It is, more than anything, a story about cooperation.

According to Harri Kulovaara, RCCL’s Executive Vice President, (Maritime), RCCL’s spirit of cooperative innovation can traced back to its roots. “From the very beginning, the company has had the courage, resources and vision to create vessels which offered truly unique passenger experiences,” he says. “While the size, complexity and variety of onboard services have expanded significantly since then, the idea remains the same.”

360o profile – rccl

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a history of cooperation Royal Caribbean Cruise Line was founded in 1968 by three Norwegian shipowners, Anders Wilhelmsen & Company, I.M. Skaugen & Company, and Gotaas Larsen. Two years later, the company launched its first vessel, Song of Norway. Kulovaara says that the vessel was the industry’s first purposebuilt cruise ship, design specifically for warmweather cruising. “We view the development of our cruise concepts as an evolutionary process, so that one vessel class builds on the features of the previous class,” he says. “You can find design elements on Oasis of the Seas which were first introduced four decades ago, on Song of Norway.” Indeed, the famous Viking Crown, a feature of every RCCL vessels built since the 1970s, remains a key element of Oasis of the Seas.

While ownership of RCCL (now part of Royal Caribbean International) has changed over the years, the spirit of innovation remains.

“Many of the ideas you see on Oasis of the Seas may seem new, but most are really concepts we have been working with for years.”

For example, Kulovaara says, the split, open air superstructure found on Oasis began with an atrium – a multi-deck open space in the middle of the vessel – first introduced in the in Sovereign Class vessels in the late 1980s. This concept was later expanded to create the Royal Promenade, a much larger open space, lined

with shops, restaurants and (crucially) inward facing cabins with windows, introduced in the Voyager class vessels almost ten years ago. ”The technology which enabled us to build an open air park on Oasis of the Seas did not happen overnight,” he says. “It looks revolutionary, but in fact, it is evolutionary.”

As the size and complexity of the vessels grew, RCCL has increasingly relied on the skill and expertise of its network of suppliers to help the company achieve its ambitions.

RCCL’s long term relationship with shipyards, such as Meyer Werft and STX Europe (which now owns both Chantiers de l’Atlantique in France and the Turku shipyard in Finland), has developed over time. innovation, one class at a time Kai Levander, who recently retired as Senior Vice President of naval architecture for STX Europe and worked on many Royal Caribbean vessels throughout his long, distinguished career, says that the company was very effective in collecting consumer data from passengers and travel agents and translating that information into more innovative designs. “RCCL has been successful in identifying changing demographics and expectations of cruise passengers,” he says. “This data has lead to new concepts, which RCCL shares with the yard. Our job has been to provide naval architecture, engineering and design solutions to help them achieve their ambitions.

RCCL always puts the passenger first, and they never let us forget that.”

Kai Levander explains that as more young people and families started to go on cruises in the late 1980s, the demand for more choice and activities onboard grew, which lead to increasingly large vessels. At the same time, RCCL recognised the passenger preference for balconies and windows, which created some innovative design challenges. “To get more balconies, we added more decks and developed the Royal Promenade concept to offer passengers inward facing windows, and later, a split superstruc-

cooperative approach to innovation In addition to shipyards, Royal Caribbean has built long-term relationships with a broad network of trusted suppliers. According to Anders Aasen, Associate Vice President, Marine Technical Services for Royal Caribbean, the company’s close cooperation with suppliers is in part a reflection of changes in the shipbuilding industry.

“Over the past decade, shipyards have embraced an outsourcing production model,” he says. “In addition, the increased size and complexity of the vessels we build demands close cooperation, so we tend to work with companies and people who share our values and business culture.”

360o profile – rccl

ture to provide inward-facing balconies, as you see on Oasis,” he says. “These steps required that we rethink how passengers and crew move around the vessel, both from a safety perspective and to avoid congestion,” he says.

Adding more decks required some unique design solutions to assure both stability and structural strength and split superstructure designs required a fresh approach to ship design.

Indeed, Levander says that construction of Oasis could not begin without first mathematically modelling every plate, frame and beam to complete Finite Element (FEM) calculations.

Other long-term technical innovations include refinements to the vessel production process to reduce construction costs and improve maintenance, improved passenger facilities and onboard services, improvements in fire protection, passenger flow, life saving appliances, more fuel efficient diesel electric power plants, and new layout solutions to open up more space for all these features.

But Kai Levander notes that to fully understand RCCL, shipbuilders, like STX Europe, have to understand the end user. “RCCL vessels have not only become larger, but they have become a lot safer,” says Levander. “In my view, Oasis represents a crowning achievement for the company, but in the end, the passengers will decide whether or not we got it right.”

Above: Oasis of the Seas was constructed in 181 separately assembled blocks, which were joined together in sections. Below: The stern of the Oasis holds the Aqua Theater, which will include automated water fountains and a spectacular diving show. At the bow, space for four bow thrusters can be seen behind the bulb.

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Above: Oasis of the Seas is equipped with three fully rotating Azipods, a first for RCL. The vessel was floated in November, 2008. Below: Oasis of the Seas, during its first sea trials last summer. The vessel is scheduled to sail to Florida in November, where it will begin its maiden cruise in December.

Aasen says the company has embraced what he calls a “cost-sharing” model of development. ”We work in partnership with suppliers to develop better solutions,” explains Aasen.

“We get a better vessel, and they get product refinements that help them gain market share.”

Aasen (who in addition to being a marine engineer, has cruised aboard all Royal Caribbean vessels to better understand the passenger experience) notes that unlike many competing cruise companies, RCCL employs many experienced engineers and technicians, which not only verify design concepts during the development process, but contribute valuable ideas.

ABB Marine, has supplied 41 Azipods to Royal Caribbean (including vessels and newbuildings operated by RCCL and Celebrity Cruises) over the past decade, acknowledges RCCL’s technical contributions. ”It’s a true partnership,” says Jyri Jusslin, Senior Vice President ABB Marine. “RCCL is very demanding. They know what they want and have good ideas on how to get there.”

There are three fully rotating Azipods on Oasis of the Seas – a first for both companies -- and according to Jusslin, the reliability of these pods is critical for RCCL. “The first Azipods we provided to RCCL went two and a half years between drydocks,” he says. “Together with RCCL, we have pushed periods between dry docks to five years. Our shared goal is to reach 10 years between Azipod-related drydocks.”

Aasen says that the reliability of the ABB Azipods has exceeded expectations. “We have in excess of 1.2 million running hours with ABB and no unscheduled drydocks due to faulty Azipods,” he says. “That kind of performance builds confidence.”

In addition to working closely with its suppliers, Aasen says RCCL also encourages suppliers to work together. “Managing the relationship between owner, the yard and the hundreds of suppliers working on any single critical reliability

vessel is one of the most challenging aspects of any build, which is why close cooperation is important,” he says. “While coordinating suppliers is mostly the responsibility of the yard, the owner sets the tone and we look for suppliers who share our cooperative spirit.”

One area where suppliers must work together with Royal Caribbean is in the bridge control system. Captain William (Bill) Wright, Senior Vice President of RCCL and the Captain of Oasis of the Seas, says that many different components had to come together to make the system meet RCCL’s requirements for such a large vessel. “Oasis has about 15,000 square meters of sail area, so manoeuvring the vessel in and out of small or busy ports in challenging wind and sea conditions requires a powerful and dynamic control system,” he says. “Oasis would not be possible without the control, flexibility and power these ABB Azipods provide.”

With six diesel electric engines delivering close to 100 MW of power to three 20MW Azipods and four large 5MW bow thrusters, Oasis has a complex and powerful propulsion system.

To transfer all that power to the bridge fell to Kongsberg Maritime which was contracted to supply the power management system and the dynamic positioning (DP) system, among other automation systems.

According to Rolf Taxt, Kongsberg Marine’s Project Manager (Integrated Control Systems), the company worked closely with the yard and RCCL and a number of sub-suppliers to deliver the right systems. “Oasis is among the largest, most challenging projects we’ve ever worked on,” he says. “It is a credit to RCCL’s personnel and the yard that everything has gone smoothly. If they don’t like something, they let us know, and we fix it. We both want the best solutions, not conflict.”

Indeed, Captain Wright was heavily involved in the control system, from concept development to the factory acceptance test, and cruise control

While the open air split superstructure Oasis of the Seas represents a remarkable technical achievement, the vessel’s unique design created some significant challenges Det Norske Veritas (DNV), tasked with ensuring the vessel’s safety. According to Karl Morten Wiklund, DNV’s Director of Passenger Ships, Oasis’s design does not conform to existing prescriptive regulations for cruise ships. “We worked together with RCL and STX Europe to ensure that Oasis complied with existing functional regulations where applicable, and worked with flag state officials and the IMO to develop, verify and document all new aspects of the ship,” he says. “It was a lot of work, but throughout the process, RCL consistently demonstrated their commitment to the safety of their passengers and crew.”

Wiklund, who has been involved in the Oasis project since 2004, says a number of the vessel’s features required special attention. For example, the split superstructure, which includes both the Royal Promenade and the open air Central Park and Boardwalk, created some challenges with regard to establishing fire safe zones, while the unusually large lifeboats (each large enough for 370 people) required a lengthy documentation and approvals process with relevant maritime authorities. “I would describe our relationship with RCL, STX Europe and flag state officials as a true partnership,” he says. “We all work together to achieve a common goal.”

Ideed, Wiklund notes that the relationship between DNV, RCL and STX Europe’s shipyard in Turku has lasted for four decades. “RCL has long been a pioneer in the cruise ship industry, and over the years, has worked with maritime authorities to expand rules to include everything from new muster routines to establishing redundant propulsion systems -- and now on Oasis, redundant engine rooms,” says Wiklund. “Each class of RCL vessels grows by about 30 per cent, which requires new ways of looking at ship design, statutory regulations and class rules. They push us, which has helped DNV retain and develop our technical expertise in the cruise segment.”

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A class act

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Artist’s rendering of the Boardwalk (complete with working carousel), one of seven neighbourhoods aboard the Oasis of the Seas. Note the zip line, which allows more adventurous passengers to fly from one end of the vessel to the other.

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will continue to offer feedback as he becomes more comfortable at the helm. In addition to making suggestions on the position of certain control throttles on the bridge, Captain Wright (who has experience using DP systems from his career in the offshore industry and other RCCL vessels) suggested some software refinements to ensure the system’s DP was optimised for the Oasis. “There were some functions we didn’t need and others we wanted, and with Kongsberg’s help, we ended up with a system which meets our requirements,” he says.

“In fact, there are elements to the DP system aboard the Oasis which I am confident would be of interest to the offshore industry.”

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“Oasis would not be possible without the control, flexibility and power the ABB Azipods provide.”

Captain William (”Bill”) Wright, Senior Vice President, Marine

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Artists renderings of the completed vessel, which show the Pool and Sports Zone, the Royal Promenade, and Central Park, an open air park which will be planted with about 12,000 living plants, flowers and trees.

Operations, RCCL

This story of close cooperation is common to suppliers, both large and small, who have enjoyed long-term relationships with RCCL. From Wartsila which designed the vessel’s six energy efficient diesel electric engines to Jotun Marine which provided a unique anti-fouling coating solution to the hull; Det Norske Veritas, a class society which certified the vessels and provided critical support for a number of new concepts, to the maritime consulting company, Delta Marine.

All of RCCL’s vast network of suppliers have both contributed – and benefitted – from their relationship to RCCL and work on the Oasis.

“We welcome participation of our network of suppliers, but in the end, the value of Oasis cannot be measured by cost, size, features or innovative design,” says Kulovaara. “After all, we did not build the largest cruise ship in the world to set a record. Oasis of the Seas is large for one reason – to enrich the passenger experience.” ||| the passenger decides

How to turn a harbour into a living area?

In many cities the harbor is located close to the town center. The scenery of the harbor given by water and huge vessels attracts almost everybody. If the air pollution, the noise and vibrations can be reduced, the whole area gets upgraded for working, shopping, living and cultural events. The city becomes more attractive due to the enhanced life quality.

Andreas Hämmerli – andreas.haemmerli@ch.abb.com

one measure to reduce the emissions of the ships while at berth, is to provide electricity from the national grid instead of producing electricity by the ships own auxiliary diesel generators. This method is known as Shore Connection or “Cold Ironing”, where the electricity for the onboard installation is provided by an Onshore Power Supply.

To provide ships with electricity, a shore-side electricity supply arrangement is required. In most of the Americas, electricity is distributed at 60Hz, which is compatible to most of the ship installations.

However, in other countries, including Europe and Asia, the electricity frequency in the grid is at 50 Hz while most of the ship installations have a 60Hz in-

Typical Vessels

stallation. Therefore a ship using 60 Hz electricity will require that the frequency is converted to 60 Hz before connecting to the grid. system requirements of connecting a vessel

The power consumption of a ship depends on the type and size. Ferries, Ro-Ro ships and freighters usually have a low consumption of power. Others like container ships with slots for refrigerator containers, LNG tankers and cruise ships have a power demand while at berth of approximately 10 MVA. The table 1 gives some typical data.

The grid voltage is reduced by a transformer, the following converter changes the frequency from 50 to

Frame Size

Supply Voltage

Leisure boats Ferries Freighters

>25kW < 1MVA

400…690V

Single Power Supply for each ship Onboard installation common

Ferries Freighters Oil Tanker Ro-Ro-Vessels

1 … 3MVA

400…690V 6.6kV

Single Power Supply

Ferries General Cargo Ro-Ro-Vessels

3 … 9MVA

6.6kV 11kV

Container Ships LNG Tanker

3 … 9MVA

Container Ships LNG Tanker

9 …18MVA

6.6kV 11kV

Group Power Supply

Megayachts and small Cruise Ships

9 …18MVA

690V 6.6kV

Single power Supply for each ship

> 18MVA

6.6kV 11kV

Group Power Supply

Cruise Ships

Onshore Power Supply Concept

Group Power Supply feeds several berths

Single power Supply for each ship

shore connection – 50-60Hz power conversion

author:

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shore connection â&#x20AC;&#x201C; 50-60Hz power conversion

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Figure 2: The structure of an Onshore Power Supply

60Hz and finally in a shore side kiosk a second transformer separates the onshore grid from the onboard grid. This is required since the earthing systems of the two grids are very different.

Finally there is a control system and of course the cable to the ship. For container vessels the cable wheel is preferably located on board since the space along the terminal is used by cranes. In contrast to that the cable wheels are based on the terminal for cruise ships. group power supply A port or terminal hence needs to be able to accommodate several vessels at one time with an aggregated power demand of 15â&#x20AC;Ś50 MVA. For container terminals and ro/ro terminals goods, cargo and containers there is heavy traffic around the quays and all space is used for either storage of goods or for roads. In city-ports houses, commercial centers, roads and pedestrian zones are all in the vicinity of the quay giving no or little possibility to build necessary installations for shore-side electricity. More over the aesthetics is important for all ports but especially to the city ports where all installation needs to be built to fit into surrounding environment. To solve this problem ABB has developed an onshore power supply concept

based on a centralized indoor frequency converter allowing the port to place the equipment far away from the busy quay and moreover design it to fit the surrounding architecture. frequency converter pcs 6000 ops The state of the art frequency converter PCS 6000 OPS connects two grids of two different frequencies and converts 50Hz into 60Hz or vice versa. Apart from the capability to transmit real power, the converter allows to control the reactive power on the ship as well as on the shore side. This function offers a maximum flexibility to adjust to the customers needs. The converter is designed for Medium Voltage Shore Connection Systems. The draft of the IEC specification 60092-510 is already considered.

The converter is assembled on a solid Aluminum frame that fits into any substation building. For outdoor use a fully containerized solution is well established in many applications.

The latest IGCT (Integrated Gate Commutated Thyristor) technology is employed which combines both the advantages of a common GTO and the IGBT (Insulated Gate Bipolar Transistor), the low conducting losses and controlled state transition, respectively.

shore connection – 50-60Hz power conversion

Figure 3: On-shore installations at a terminal.

The water cooling system with redundant pumps conveys the water-glycol mix to the power converter and the heat exchanger. The losses are dissipated to the ambient air via the heat exchanger. Additionally to the water/air heat exchanger a heat pump can be installed to heat any tap water.

The optimum solution for the high-speed control requirements of power converters is provided by the well known AC 800PEC controller. This is a high-end controller belonging to ABB’s AC 800 family. It is configured and programmed with ABB’s Control IT ®) for

Figure 4: CS6000 static power converter, a voltage source inverter with IGCT semiconductors.

open and closed loop control functions. The controller combines a very powerful CPU (PowerPC) and large Field-Programmable Gate Array, which suits AC 800PEC to control demanding power electronic systems. The AC 800PEC I/O modules are connected via high-speed point-to-point fiber optic connections.

The PCS 6000 frequency converter is employed in many applications also such as railway grids and wind power and has proven its high reliability and availability. |||

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ABB solution greens global shipping A pioneering ABB solution that cuts greenhouse gas emissions and reduces ship fuel costs has helped the major North Sea port of Gothenburg win its second international award for cleaning up shipping and the seas. was developed for a ro-ro (roll onroll off) terminal at the Swedish port of Gothenburg in 2000 and was the first in the world to provide ships with high voltage electric power delivered by cable from onshore during their time in port.

The ABB solution helped the Port of Gothenburg win two environmental awards, the 2008 Clean Seas Award given by Lloyd’s List and the 2004 Clean Marine Award given by the European Union.

The process provides a ship at berth with shoreside electrical power when its main and auxiliary engines are turned off. In this way, its equipment, refrigeration, cooling, heating and lighting can receive continuous electrical power in loading and unloading.

the abb solution

shore connection – 50-60Hz power conversion

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In total, Sweden’s shore-to-ship electrical connections - at Gothenburg, Stockholm, Helsingborg and Pitea - save about 1,900 tonnes of fuel each year and reduce carbon dioxide emissions by 6,000 metric tons, according to the Swedish Environmental Research Institute (IVL).

Ships plug into an onshore grid, in contrast to the previous method in which ships used their auxiliary diesel engines to generate electricity in port, consuming large volumes of fuel and emitting high levels of greenhouse gases and noise.

The Gothenburg installation has been so successful that an additional three terminals at the port have since been equipped with the ABB solution, helping the port authority to become the international benchmark for shore-to-ship power supply.

Providing shore-side electrical power is also known as “cold ironing,” referring to a time when ships had coal-fired iron engines. Ships docked in port, turned off the engines and let them go cold, hence the term. cold ironing

“Shore-side electricity has a large potential to reduce the impact from shipping on health and on the environment,” IVL research Erik Fridell told a conference on shore connections at Northern Maritime University in May 2009. “The main advantage is the reduction in emissions of toxic gases in port cities.”

Harbor facilities around the world have begun to take a closer look at shore-to-ship connections as a means to reduce emissions from ships in port and improve air quality in surrounding communities.

Shore connections are now available at ports in the United States, including Los Angeles, Long Beach, San Francisco, San Diego, Seattle and Juneau, in Canada at Vancouver, and in Europe at ports in Germany, Sweden, Finland and Holland.

In the U.K. the port of Southhampton announced in July 2009 it will also consider implementing shore-to-ship electrical connections for cruise vessels in port.

In May 2009, European Commissioner for Maritime Affairs and Fisheries Joe Borg told a conference of European cruise companies in Rome that shore connections is one of the policies being pushed by the EU as part of an Integrated Maritime Policy.

Compared to standard high-sulfur engine fuel, the ABB high voltage solution reduces carbon dioxide emissions by 50 percent and other greenhouse gases by up to 97 percent. The emission reduction is significant, even compared to the low-sulfur fuel that is set to become mandatory for ships visiting European ports in 2010.

If connected to a renewable energy source like wind, hydro or solar power – which the port of Gothenburg is considering - the solution has the potential to eliminate greenhouse gas emissions during ship stopovers.

Known as High Voltage Shore Connection (HVSC), the ABB solution is a complete, compact, modular and highly flexible system. About a dozen cruise ships are currently outfitted with the technology.

The products used in the solution – substation, transformers and frequency converters (also known as AC drives) – are core ABB technologies in which ABB is the global market leader. ||| supported by eu

Shore connection; onboard installation Shore power connection to avoid the use of auxiliary engines in port is gaining wider acceptance. Marcus Martelin, (Business Development for Marine Service), assesses the lessons learned so far and their application to retrofitting existing ships.

Marcus Martelin â&#x20AC;&#x201C; marcus.martelin@fi.abb.com

High Voltage Shore Connection (HVSC), the ABB solution for retrofit comes as a complete, safe and highly flexible system. ABB has retrofitted such solutions for cruise vessels in operation in North America.

The concept is to provide ship electrical loads with power from the onshore grid, with seamless connection and disconnection, and without disturbance to the electric power system on board.

The driving force behind the installation of HVSC is increased environmental concern, and the request from shore authorities to reduce emissions of NOx, SOx, and particulates in harbours. In such areas, the density of ships is high and the emissions from running auxiliary engines are a significant contributor to the local pollution.

known as

The ABB solution includes switchgear, control and supervision hardware and software, high voltage and low voltage cables, and the power management system onboard the vessel. The design is based on the strictest requirements for safety and reliability, in compliance with IEC standard 60092-510, which is still in the draft phase.

Typically, the vessel power plant onboard cruise vessels consists of 5 or more diesel engine driven generators, with power generator capacity of more than 40MW, and a shore power demand that may exceed 10MW. The ship network voltage level is typically 11kV at 60Hz frequency. Where the on-shore grid is 60Hz, e.g. in the USA, frequency conversion is not needed.

In contrast, other geographical areas operate using 50Hz distribution system.

Figure 1: Shore connection system; onboard installation; single line diagram.

shore connection â&#x20AC;&#x201C; onboard instalation

author:

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shore connection – onboard instalation

main principle The shore connection system onboard the vessel comprises of the following main components, Figure 1: - Shore connection (or embarkation or OPS) cabinet, where the feeding power cables are connected - Sockets for the cable connections - Cables between the embarkation cabinet and main switchboard - Cubicle in the vessel’s main switchboard for connection to vessel’s network - Protection and control systems - Monitoring PC panel with mimic functions - Accessories like cable tension monitoring, shell door and splash screen

Figure 2: Shore connection switchboard

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The power and signal cables from the shore side supply are connected to the shore connection cabinet. The cabinet is a factory-assembled three-phase, air–insulated switchgear and it must be provided at a suitable location, near to the supply point, for the easy reception of the heavy shore connection cables. The main components in this cabinet are: - Circuit breaker (Marked as “A” in the single line diagram) - Control and measuring items, like the IAS Remote I/O unit to provide the Integration of the “Shore Connection” functionality into “IAS”.

- Multifunction protection relay (REM/REF) - Shore Power Plugs and Neutral / Ground Cable Plug The shore connection cabinet is equipped with a marine approved circuit breaker, the purpose of which is to provide connection and disconnection and also to facilitate protection of the cable between the shore connection cabinet and the main switchboard.

A REM/REF protection relay unit is used for protection, measurement, and monitoring of the ship’s shore connection.

Figure 3: Connection sockets.

vessel’s main switchboard There has to be a dedicated cubicle in the ship’s main switchboard for the connection of shore power. For retrofit projects the cubicle can be a spare cubicle within the existing switchboard or an add-on cubicle, equipped in a similar way

Typically, new VDU pages are also created in the vessel automation, in order to monitor the sequence and power consumption.

The protection philosophy fulfills the existing IEC and ISO standards and is designed to minimise the possibility of personnel injury.

Furthermore, the purpose of the protection system is to prevent or minimise damages by generating an alarm or disconnecting faulty parts to prevent the failure from propagating to the rest of the power system.

To fulfill safety rules, the termination of the shore cable in MV equipment is only allowed when the system is earthed. For this reason there are interlocked earthing switches in both shore side and ship side switchboards. protection philosophy

Figure 4: Typical VDU for Power Management System

Normally, the selectivity in the ship network is based on the high short circuit power of the generators. When fed from the shore side grid the selectivity is evaluated case by case for the ship in question.

The secondary circuit breaker on the shore side has to ensure the protection of the feeding cable and ship network.

The following protection functions are typically included in the MV switchboard.

- Short circuit over-current - Non-directional over-current - Directional over-current - Differential current - Over-voltage - Under-voltage - Reverse power - Under-frequency - Negative phase sequence - Earth fault - ARC protection Furthermore, if one of the circuit breakers on the vessel side is opened, the shore side CB will also open automatically.

Cable tension is monitored and safety measures are taken before the energised cable can be unexpectedly pulled out by external force.

The possibility of human error is further reduced by implementing a detailed connection and disconnection procedure and authorisation protocol.

shore connection – onboard instalation

to a generator incoming feeder. The solution depends on the ship’s original design; which varies from vessel to vessel.

This circuit breaker “B” is the one that provides the actual connection with the “Shore Side” and is involved in all the procedures for synchronization and connection, the interface with the existing PMS arrangement and the new “shore side” network unit.

In order to operate the shore connection with a power transfer in a continuous and safe sequence, the vessel automation and PMS system need to be modified. Generally speaking the shore grid is treated as an additional generator that is connected to the vessel’s network.

The shore connection logic sequence is implemented in the shore connection PLC. The “Shore Connection Mode” application software takes into consideration all interfaces involved as: 1. The main switch board.

2. The diesel generator set and load characteristics.

3. The diesel generator set governors and mode of operation.

4. Generator’s voltage regulators (AVR) and mode of operation.

5. The new hardware unit with circuit breaker interface with all related safety and control circuits.

6. The IAS and PMS interfaces with their new logic and operating modes

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shore connection – onboard instalation

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Figure 5: Cable entrance through the vessel’s hull.

shore connection operation The following main sequence is used to ensure safe connection of the shore termination: 1. The secondary CB on the shore is open and both CBs on the ship side (shore connection cabinet and main switchboard) are open 2. All earthing switches are closed (not possible to close CB) 3. Safety checks 4. Manual connection of all cables to the shore connection cabinet 5. Circuit breakers A and B can be inserted 6. ECR panel key and “permission” activated by the user

Once all these requirements have been fulfilled, the “MODE SELECTION” on VDU screen will popup and the operator is allowed to select the “START SHORE MODE” function. At the same time as the “START SHORE MODE” is activated, any heavy use of the PMS is inhibited.

As soon as the operator chooses the “START SHORE MODE”, the logic sends “authorisation” to shore, which allows closure of the secondary circuit breaker on the shore side transformer. This circuit breaker will then be closed manually from the shore side. The cables are live and when the correct voltage and phase sequence are detected, an input to IAS will be activated. IAS will then give order to circuit breaker “A” to close.

After the circuit breaker “A” is closed, the synchronizer in the main switchboard will be started and the running diesel generator will be put in droop mode.

The AVR will enter voltage matching mode. As soon as the synchronizer detects the correct phase sequence, the circuit breaker B closes and a load ramp-down function is activated to download the generator set.

The ramp down brings the load down and the diesel generator’s circuit breaker is opened; followed by a “standard” cooling down and stopping sequence on the diesel generator set. The setting of the ramp can be done on the VDU. As shore connection of vessels is used more widely vessels already in operation will increasingly deman modification and the retrofit installation of medium voltage switchboard panels and control systems. As noted, ABB has provided such systems for cruise vessels operating in Northern Americas, and similar systems are expected to be required also for other vessel types; such as tankers, LNG carriers and container vessels. As the onboard power demand can range above 10MW in magnitude, the shore connection has to be at medium voltage levels. For retrofit installations of cruise vessels made by ABB, 11kV has been applied; while for other vessels, 6.6kV may also be applicable.

Despite the fact that the actual connection to shore power is fully automated, the possibility of human error must still be minimised. This is achieved with a well designed protection system, together with implementation of adequate operating procedures and safety checks both to the crew and the personnel on shore. ||| references

International Standardization: /1/ IEC/PAS 60092-510:2009: Electrical installations in ships -- Special features -- High Voltage Shore Connection Systems (HVSC-Systems) /2/ ISO/CD 29501: Ships and marine technology -- On shore Power supply, “Cold Ironing”

The future is high powered Recent advances in the field of high voltage power semiconductor devices with applications in the marine industry provide a feasible path for future higher power systems with exceptional performance. authors:

Iulian Nistor – iulian.nistor@ch.abb.com ||| Munaf Rahimo – munaf.rahimo@ch.abb.com ||| Tobias Wikström – tobias.wikstroem@ch.abb.com

such as Insulated Gate Bipolar Transistor (IGBT), Integrated Gate Commutated Thyristors (IGCT) and their counterpart diodes have enabled a tremendous technical revolution in the field of AC drives. Nowadays, the benefits of AC drives or frequency converters are widely acknowledged by end users in the marine industry.

Modern AC drives provide high system functionality and integrity, yielding long term benefits. Smooth control, energy savings and soft start capabilities are strong advantages found in applications controlled by frequency converters. Improved efficiency, reliability and serviceability in a compact physical size have increased the demand for such AC drives: through continuous innovation ABB has become the world’s leading supplier of variable speed drives for the marine industry.

Power semiconductors are to be found at the core of all of these converters - tiny Si chips, or large Si wafers – which silently and relentlessly turn on and off the flow of the electrical current, allowing for unprecedented levels of control, reliability, and power density. The recent developments of these two power semiconductor platforms have enabled higher power ratings and better overall electrical performance.

ABB offers a complete range of semiconductor products for drives applications, for example IGBTs and IGCTs.

Figure 1: ABB IGCT showing the GCT component with the integrated gate control unit (4.5kV IGCT 5SHY 55L4500) or 3D exploded package

IGCT& MV Drives The introduction of IGCTs signaled the start of a true revolution in the area of Medium Voltage Drives (MVD) - ABB introduced its first IGCT based MVD in 1998. The previous design of MVDs based on GTOs required dV/dt snubbers in the circuit. The IGCT, turning off like a transistor, eliminates the need for the snubber, thus substantially decreasing the size and the cost of the system. In such applications IGCTs are normally used in two or three level topologies (2L or 3L-NPC) as one device per function. 3L-NPC voltage source inverter topologies are particularly preferred at higher voltages because of the limited voltage rating of the semiconductors. IGCT based MVDs today are offered in phase-to-phase voltage classes of 2.3, 3.3, and 4.16 kV rms.

the integrated gate commutated thyristor (igct)

Since its market introduction in 1996, the IGCT has gained importance as a semiconductor switch characterised by inherent advantages: – low on-state – fast switching capability – possibility to fit a single device with a current capability of thousands of Amperes.

The IGCT concept is based on a development of GTO devices. As such, the IGCT is a bipolar device with a thyristor structure and conducts the current

IGBT & LV, MV Drives IGBTs require no snubber circuits so the design of drives is simplified significantly. The IGBT can inherently limit the short circuit current in the case of a failure, in such a manner that the device can be safely turned-off without damage. In addition, compared to IGCTs which require an inductor to limit the speed of the commutation process, the IGBT can be efficiently controlled only by changing the value of the gate resistor. Similar 2L or 3L-NPC topologies as for IGCTs are used for IGBT based converters.

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Figure 2: The Standard IGBT HiPak module family

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Figure 3: The SOA capability of the last three generations of 91 mm, 4.5kV IGCTs at 25°C and 125°C. The new HPT technology has led to a change in how the SOA is limited; previously, the cold SOA was limiting – with HPT, SOA is high temperature limited (as with IGBTs).

with low on-state losses. The device is very compact, having the gate drive unit incorporated to minimise the stray gate inductance in the circuit connecting gate and cathode (Figure 1). This allows the IGCT to be turned-off like a transistor, in a “hard driven” mode, where the anode current is commutated from the cathode to an external capacitor during turn-off.

Very high di/dt’s (thousands of amps/us) are normally reached during this fast turn-off process. Thanks to this, IGCTs have become a top choice today in numerous applications such as converters (industrial medium-voltage drives or MVDs), as well as railway interties and other energy management systems (typically above 2MW). At the same time, the high ratio between the active silicon area and the junction termination area has made the IGCTs a very attractive choice in high voltage applications (above 6.5 kV). Currently, IGCT products are available from ABB as either single wafer devices - Asymmetric IGCT (AS), or monolithically integrated with the freewheeling diodes – or Reverse Conducting IGCTs (RC),with current and voltage ratings starting at 4500V and a few hundred amps up to 6500V and 4000A. Therefore, it is no surprise that IGCTs became the power semiconductors of choice for the powerful and versatile ACS6000 drive widely used in the marine industry. This multi megawatt drive successfully addresses the requirements of modern propulsion schemes for floating production facilities, dynamically positioned drilling vessels, shuttle tankers, service ships and large passenger vessels. Up to now, ABB has equipped over 500 vessels and floating structures with ACS6000 medium voltage variable speed drives. This is equivalent to a total rated power in excess of 6,500MW. the insulated gate bipolar transistor (igbt

Figure 4: Turn-off waveforms for the 4.5kV 91mm HPT-IGCT at 25°C.

)

As early as 1992, the ABB researchers presented the world’s first sample of a 4.5 kV, 600 A IGBT module.

Following this success, the full scale manufacturing of IGBTs started in 1998 at the ABB factory in Lenzburg, Switzerland. This factory remains the only factory in the world dedicated exclusively to the manufacturing of high power IGBTs. Since its introduction, IGBT voltage and current ranges have been continuously increased and, over the past two decades, many performance breakthroughs

Figure 5: Evolution of IGBT technology.

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have been achieved [5]. The IGBT presents a number of inherent advantages and is now directly competing with IGCTs in various megawatt power electronic applications. These advantages include: – controlled low power driving requirement – short circuit self limiting capability – it presents no unstable state between turn-on and turn-off The IGBT concept is based on a bipolar transistor with the base current delivered through a MOS gate controlled channel. Two competing technologies are now present in the market, one based on planar cell design (more common at IGBT voltage ranges higher than 2500V), and the second based on trench gate design (typical for IGBTs with voltage ratings lower than 1700V). Due to the presence of a MOS controlled channel, the IGBT current will inherently saturate in the conduction state. In addition, the turn-off process is less complex than in the case of the IGCT. Once the positive voltage that creates the inversion channel is removed from the gate terminal, the current is prevented from flowing in the base of the IGBT and the device will turn-off like a normal bipolar transistor.

ABB now offers a wide range of IGBT products targeted to provide megawatt applications such as traction, industrial drives and transmission and distribution. Today, high power IGBT press-pack and insulated modules are available in voltage/current ratings ranging from 1700V/3600A to 6500V/750A.

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Figure 6: SPT+ IGBT on-state Vce(sat) reduction for voltage ratings up to 6500V.

igct hpt technology: wide safe-operating-area

Despite its advantages, one of the main limitations of the IGCT was the scaling of its Safe Operating Area (SOA) with the device size. The SOA is defined in connection with the maximum controllable turn-off current of the IGCT. In small area IGCTs, the SOA has been shown to exceed 1MW/cm2, however for large area devices the SOA has been restricted to values of 200-300kW/cm2.

The HPT platform has been introduced to address this sub-linear SOA scaling issue for large area devices. The HPT incorporates an advanced corrugated p-base design that ensures controlled and uniform dynamic avalanche operation with better homogeneity over the diameter of the wafer during device turn-off.

The HPT has been proven for IGCT products with voltage ratings up to 6.5kV. Fig. (3) shows an example of

Figure 7: 3.3kV SPT+ IGBT turn-off SOA under extreme conditions.

IGCT vs. IGBT cell design and operation Both the IGCT and IGBT wafers consist of a massive parallel connection of smaller segments or unit cells. In the case of the IGCT, every unit cell has the structure of a thyristor.

For a 91mm IGCT wafer for example, not less than 2700 segments are connected in parallel, laid out concentrically in ten segment rings. In the case of the IGBT, the unit cell is basically a MOS-controlled bipolar transistor. Every IGBT chip can contain up to 100.000 such cells per cm2. There are a number of differences between these devices. First, as the IGCT is a thyristor with a diode-like on-state, it can be regarded as a benchmark for an optimal IGBT. Intricacies of IGBT operation make it difficult to achieve IGCT-like

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Fun facts The electrical losses in power semiconductor are converted in heat. The heat flow can be as high as 100W/cm2, and has to be efficiently and rapidly removed from the semiconductor by using cooling systems. For comparison, a cooking plate that would generate a similar amount of heat as a power semiconductor would be able to bring the water to the boiling point in about 5 seconds!

on-state. Second, the high-impedance MOS gate of the IGBT facilitates less control effort compared to the IGCT. Third, the current-limiting feature is inherited from the MOSFET in the IGBT, which lends intrinsic short-circuit protection to a well-designed device. And fourth; since the IGBT does not pass through a meta-stable state when switching, the device can be controlled via the gate during switching. This feature can be used to reduce the number of passive components in the system. Recent IGBT technology advances have erased the loss performance gap to a large extent, leading to that there are very few applications where the optimal choice of technology is trivial.

igbt spt+ technology: lower losses and larger safe-operating-area

The IGBT has benefited from rapid progress in cell designs (planar, trench, enhancement layers) and bulk technologies (Punch-Through PT, Non-Punch-Through NPT, Soft-Punch-Through SPT or Field Stop FS) which developed from low current and low voltage beginnings. The most recent low loss and high SOA improvements for high voltage IGBTs were mainly due to the introduction of the SPT or FS thinner silicon concepts combined with advanced enhanced planar or trench emitter structures. Similar advances were also achieved for the anti-parallel freewheeling diode to match the continuously improving IGBT. For example, the SPT+ development was motivated by the need to reduce the total losses of the IGBT and diode without sacrificing the high SOA capability and Switching-Self-Clamping-Mode (SSCM) of operation under extreme conditions. The SPT+ IGBT platform is based on an Enhanced-Planar cell design (EP-IGBT) and has been designed to reduce on-state voltage substantially while increasing the turn-off ruggedness even above that of the SPT-IGBTs [7]. The SPT+ IGBT technology enabled the establishment of a new technology curve benchmark over the whole IGBT voltage range from 1200V up to 6500V as shown in Fig. 6. The values for Vce(sat) are obtained at the same current densities and for similar turn-off losses per voltage class. Similar improvements for the diode were also introduced with an SPT+ diode technology to match low loss IGBTs [8].

The remarkable SOA performance of the 3.3kV IGBT chips is shown in figure 7. During extreme turn-off conditions, a single chip (1cm2) was capable of dissipating 1.5MW while sustaining strong dynamic avalanche and a relatively long period of SSCM.

future power technology development trends

The main development trends for power devices can be summarised as follows: – increasing the power ratings while improving the overall device performance – reduced losses – higher operating temperature – increased robustness – better controllability – reliable behaviour under normal and fault conditions.

An important aspect to mention here is the recent trend towards increased operating temperatures compared to the traditional 125°C maximum junction temperature operational limit. The low losses and high SOA of modern IGBTs and diodes has enabled this step to be taken while also focusing on reduced leakage currents and improved package reliability as the major limiting factors. An increase of around 10-15% in total output current capability can be predicted with this approach.

10kv igct and diode: extending the voltage range

For IGCT the focus of technology development will be on: – Increased voltage ratings – Increased current ratings through the use of larger area Si wafers – Soft freewheeling diodes monolithically integrated with the IGCT – Higher operation temperature For example, the development of a 10kV IGCT and diode [4] for enabling voltages in a 3-level configuration of up to 7.2kV rms without series connection will open up new fields for the use of power semiconductors in power conversion. By using the advanced HPT corrugated p-base design, the envisaged turn-off capability of a 10kV IGCT was much higher than that which could be previously expected for a device rated at this voltage level. 91mm 10kV IGCT and diode demonstrators have been produced and show promising results and good switching behaviour as can be seen in Fig. 8.

Due to the high SOA and improved scaling capability of the HPT concept (i.e. higher blocking and larger area diameters), the technology will also become an enabler for future IGCT generations with increased

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the powerful turn-off switching capability of the new 4.5kV 91mm HPT-IGCT generation. The 4.5kV HPT IGCT was capable of turning off in excess of 5000A by withstanding extreme conditions with a large stray inductance, equivalent to a 50% increase in the IGCTSOA. The IGCT was also able to reach and sustain a new operational mode referred to as the SwitchingSelf-Clamping-Mode (SSCM) as the overshoot voltage reaches the static breakdown voltage. This provides new opportunities for control and fault handling compared to the standard IGCT devices.

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power handling capabilities. Therefore, in the coming years, development trends of IGCTs will be able to target further reductions in the device static and dynamic losses, higher operating temperatures and larger wafer diameters with higher current ratings. the bi-mode insulated gate transistor (bigt)

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Figure 8: Waveforms of snubberless turn-off for a 91mm 10 kV Diode (top) and IGCT (bottom), IT=2 kA.

Figure 9: The Reverse Conducting RC-IGBT concept.

Currently, it could appear that the development of high voltage silicon power devices has reached a limit with regards to further reductions in the device total losses. The state-of-the-art SPT/FS structures are close to the so-called “Silicon Design Limits” from the thickness point of view and the emitter plasma enhancement will only provide smaller steps with fine optimisation of the IGBT cell designs. In addition, the extremely robust modern IGBT designs already provide the necessary SOA performance with adequate margins. Therefore, more advance device concepts are required as the trend continues for next generation megawatt systems with increased efficiencies.

Such an advanced design is the integration of an IGBT and diode, or what has been normally referred to as a Reverse Conducting RC-IGBT [9]. The realisation of such a concept has always been hindered by design and process issues resulting in a number of performance drawbacks such as the on-state snapback phenomenon, IGBT vs. diode losses trade-offs, softness, and SOA. Recent development efforts in the direction of solving the above issues have resulted in an advanced high voltage RC-IGBT concept referred to as the Bimode Insulated Gate Transistor (BIGT) [10]. The BIGT differs from a state-of-the-art RC-IGBT in the following respects: – can operate in Bi-mode operation as an IGBT & Diode

Figure 10: 3.3kV/1500A BIGT (140x130) mm module nominal turn-on (left) and turn-off (right) and associated losses. (I: 500A/div, V: 500V/div, Vge: 10V/div, Time(x): 1usec/div)

Continuous developments have also been reported in Wide Band-Gap (WBG) materials such as SiC and GaN for power semiconductors. The interest in these materials is motivated by the ten fold thinner base region structures having substantial loss reduction potentials and the high operating temperature capability when compared to silicon. With the clear progress achieved for ultra fast SiC Schottky power diodes rated up to 1700V and the wide bandgap materials

Figure 11: The evolution of the current rating of 3.3kV IGBT HiPak modules

many SiC switch concepts demonstrated recently, WBG power devices are now being regarded as the next major performance leap. Nevertheless, the current cost of such devices and some technological and performance aspects yet to be fully resolved especially for higher voltage/current devices will continue to delay the introduction of WBG components in megawatt applications. In addition, the fact that silicon power devices could still provide another major breakthrough in performance also has to be taken into account. ||| references [1] S. Klaka, M. Frecker, H. Grüning “The Integrated Gate-Commutated Thyristor: A New High-Efficiency, High-Power Switch for Series or Snubberless Operation” PCIM, Nürnberg, Germany, 1997.

[2] T. Wikström, T. Stiasny, M. Rahimo, D. Cottet, P. Streit “The Corrugated PBase IGCT , a New Benchmark for Large Area SOA Scaling”, ISPSD, Jeju-Island, S. Korea, 2007.

[3] J. Vobecky V. Zahlava, K. Hemmann, M. Arnold, M. Rahimo “Radiation Enhanced Diffusion (RED) Diode at 4-Inch Wafer” ISPSD, Barcelona, Spain, 2009.

[4] T. Wikström, M. Lüscher, I. Nistor, M. Scheinert: “An IGCT chip set 7.2 kV (RMS) VSI application” ISPSD, Orlando, USA, 2008.

[5] M. Rahimo, U. Schlapbach, A. Kopta, S. Linder “An Assessment of Modern IGBT and Anti-Parallel Diode Behaviour in Hard-Switching Applications” EPE, Dresden, Germany, 2005.

[6] M. Rahimo, A. Kopta, S. Eicher, U. Schlapbach, S. Linder “Switching-SelfClamping-Mode “SSCM”, a breakthrough in SOA performance for high voltage IGBTs and Diodes” ISPSD, Kitakyushu, Japan, 2004.

[7] M. Rahimo, A. Kopta, S. Linder “Novel Enhanced–Planar IGBT Technology Rated up to 6.5kV for lower Losses and Higher SOA Capability” ISPSD, Naples, Italy, 2006.

[8] A. Kopta, M. Rahimo, U. Schlapbach “New Plasma Shaping Technology for Optimal High Voltage Diode Performance” EPE, Aalborg, Denmark, 2007.

[9] M. Rahimo, U. Schlapbach, A. Kopta, J. Vobecky, D. Schneider, A. Baschnagel: “A high current 3300 V module employing Reverse Conducting IGBTs, setting a new benchmark in output power capability” ISPSD, Orlando, USA, 2008.

[10] M. Rahimo, U. Schlapbach, R. Schnell, A. Kopta, J. Vobecky, A. Baschnagel “Realization of Higher Output Power Capability with the Bi-Mode Insulated Gate Transistor (BIGT)” EPE, Barcelona, Spain, 2009.

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– utilises the same silicon area in both modes – operates in hard-switching conditions in both modes – replaces the current two-paralleled chip approach in future systems The BIGT offers in addition a number of device performance advantages such soft switching behaviour under extreme conditions and better diode mode surge current capability.

The initial BIGT technology demonstrators were developed for high voltage devices rated at 3300V. High current 3.3kV BIGT (140 x 130)mm HiPak1 modules were then fabricated and tested under conditions similar to those applied to state-of-the-art IGBT modules. The BIGT module contained 24 BIGT chips for the estimated current rating of 1500A. The nominal transistor mode switching characteristics of the BIGT modules are shown in Fig. 10, along with the associated switching losses at 125°C. The BIGT diode mode reverse recovery performance is mirrored in the turnon waveforms. The BIGT exhibits low losses in both modes of operation with no typical snap-back behaviour in the transistor on-state mode when compared to a standard RC-IGBT, while also maintaining high levels of SOA performance.

The advantage of BIGT is clearly demonstrated here, since this module can practically replace a similarly rated larger (140 x 190)mm HiPak2 module which normally contains 24 IGBTs and 12 diodes. The larger standard IGBT module has the further disadvantage of employing much less diode area, which is normally a limiting factor in rectifier mode of operation and surge current capability. On the other hand, when the larger (140x190)mm HiPak2 module employs only BIGT chips i.e. 36 devices, its rating can potentially reach up to 2250A.

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Innovative ship distribution systems Ever since variable speed electric motors have been applied in the control of propulsors and thrusters, the electric power grid has been run at fixed frequency and voltage in order to supply electricity to all vessel systems. Now, new and less restrictive ways of distributing electric power in ships with electric propulsion are emerging. author:

Klaus Vänskä – klaus.vanska@fi.abb.com ||| Alf Kåre Ådnanes – alf-kare.adnanes@no.abb.com

and variable speed drives to control propulsors and thrusters in electric propulsion allowed a common electric distribution system to be used for all systems on a vessel.

The power plant is then configured and controlled for a fixed voltage and fixed frequency, e.g. 690V and 60Hz. This has significant advantages when compared to operating independent electrical power systems for the vessel auxiliary systems and hotel loads, and the propulsion and thruster systems. One main advantage is that the diesel engines that typically drive the electrical generators can be loaded more optimally, thus reducing fuel consumption. Furthermore, the fault tolerance of the system increases, as unintentional stops of one diesel engine should not lead to total loss of any sub systems if more than one diesel-generator set is connected in parallel, although the limitation in power supply may lead to a reduction in some of the loads.

In such systems, the electric transmission losses are in the range of 8 to 10% of the total consumed power. The benefits of increased efficiency of the propellers and optimal loading of the diesel engines are for a range of vessel types or operations magnitudes larger than the losses in transmission, making electric propulsion both cost effective and environmentally friendly.

With continuous developments in power electronics and controller technologies, it is of interest to see if this concept can be further enhanced and improved by taking an open-minded approach to design, not limited to off-the-shelf technologies, in order to achieve: – Higher transmission efficiency – Improved fault tolerance – Reduced total weight and space

the introduction of frequency converters

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A typical electric power plant in today’s installations is shown in Figure 1, and consists of: common grid ac distribution

– Electric power generation: Normally synchronous generators driven by diesel engines, gas or steam turbines.

– Electric power distribution: A common grid AC electric distribution system of switchboards at different voltage levels, and distribution transformers for voltage adaptation, normally with power flow from higher to lower voltage levels.

– Electric loads: Any electric consumer, i.e. apparatus or equipment that is fed from the common grid. In ships with electric propulsion, the main consumers are the propulsors and thrusters, typically taking up 70-80% of the total installed load power.

– Associated control and protection systems: E.g. power management systems, protection relays, and motor drive controllers; those interact on the power consumption and system protection.

In the typical installation, the generators will generate electric power at constant voltage and frequency. The frequency is normally fixed at 60Hz, with certain installations being 50Hz; such as for Chinese and Russian vessels. The generating voltage depends on installed power and the short circuit levels of the network, with 690V, 6/6.6kV, and 11kV as the typical main generating voltages for ships with electric propulsion.

Electric Compatibility Interface (ECI) is a new term, defining the specification of the interface or connection between the generators of electric power and the electric distribution system.

In today’s common grid AC distribution systems classification requirements define the boundaries, electric compatibility interface

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Figure 1: A common grid AC electric power plant with fixed voltage and frequency in the electric transmission system.

while the actual ECI requirements will depend on whether the engines and generators are controlled in either constant or droop mode. For three different vessels, the ECI could be: – 690 ± 17V – 60H±2HzVoltage droop, speed droop – 6600 ± 165V – 60Hz Voltage droop, isochronous speed – 11000V – 50Hz Constant voltage, isochronous speed This system is well suited for using industry standard electrical apparatus and equipment for generation, distribution, and all vessel loads. This has a significant value, as well proven equipment

can be applied, which is cost efficient and achieves a high degree of maintainability and easy replacement.

Also, it allows standard engineering and installation methods to be used.

Although there are significant advantages with this ECI specification, there are also some negative effects: – Using synchronous generators, the prime movers will be forced to run at certain fixed speeds, e.g. 720RPM, 900RPM, and 1200RPM. This means, for example, that an engine cannot fully optimise the speed versus the load for maximum efficiency and lower fuel consumption and emissions cost.

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– Using alternative power sources, e.g. fuel cells with DC supply, requires a DC/AC power conversion at fixed frequency and voltage output, which becomes complex in island mode operations, for example.

– 70-80%, or even more, of the generated power, being transmitted in the fixed frequency AC system is rectified before being inverted again to control the speed of the thrusters, propulsors, pumps, and fans. In the AC common grid system, the distribution system with switchboards must also be dimensioned for this load.

– The electricity in the common grid also supplies auxiliary systems, and sensitive navigation systems. Thus, the quality of the electric supply must meet stringent requirements as specified by class and industrial standards, although 7080% or more of the load actually does not need such high quality power supply and/or creates disturbances.

– The common grid is also vulnerable to common faults; in previous generations of installations, such common faults were of concern but, today, with solutions are arrived at by fast acting control systems for power management and motor drives, such as the ABB DTC® motor controller, diesel generator monitoring systems (DGMS), and advanced protection systems.

With recent developments in power electronics and digital controllers, it is appropriate to raise the question of whether this definition of the ECI is the most optimal, and what kind of benefits would be achieved with alternative solution.

Two ideas are proposed for redefining the ECI and how electric power is distributed in ship networks. The first of these is based on existing technology used in ship applications today for multidrive applications - DC distribution. The second approach is more theoretical, though based on experience, and considers how one could design a matrix distribution system for maximum segregation and power source independence.

By the late nineteenth-century, Thomas Edison had developed the electric distribution system relying on direct current common grid dc distribution

(DC) power generation, distribution and use. This pioneering system, however, turned out to be impractical and uneconomical, largely because in the 19th century, DC power generation was limited to a relatively low voltage potential and DC power could not be transmitted over long distances. Edison’s power plants had to be local affairs, situated near the load, or the load had to be brought close to the generators. All of these negative factors for DC distribution made possible the revolution of AC distribution with transformers led by George Westinghouse. And, as we all know, nowadays systems are based on AC distribution. However, the negative factors linked to DC distribution do not apply to grids featuring short distances between power generation and consumption, as is the case in ships, and all of the positive factors then come into play. Of course, developments of semiconductor converters and control also offer much wider possibilities for DC distribution than was the case in the late nineteenthcentury.

Common DC bus technology used for a number of inverter motors is now widely available, for application to the converters for multi motor drives and those used for drilling drive applications, cargo pumps. It has also been used in thruster drives. An extension of this technology with static inverters to supply ship systems opens up a whole range of interesting concepts. One example for offshore supply vessels is shown in Figure 2.

In this system, the electric power generators supply a DC link voltage to the common DC grid. In Figure 2, the generators are of the synchronous motor type; but in principle, any kind of electric power source could be connected to the DC distribution, as long as they met the ECI requirements for this system. Different kinds of rectifiers (diode bridges buck or boost converters etc.) can be used to adapt various power sources to ECI layer.

The ECI requirements could be, for example: - 1000VDC For low voltage motor drives - 4500VDC For medium voltage motor drives The main advantages with this solution would be: - Significant reduction of the AC distribution system, and especially a reduction in the main switchboard to feed only vessel systems that need an AC supply

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Figure 2: A common grid DC electric power plant with fixed DC voltage ECI.

- Avoidance of multi winding drive transformers or active rectifiers for harmonic mitigation - Reduced energy losses and voltage drop in transmission, lower fuel consumption and environmental emissions - Easy to adapt multiple and various sources of electrical energy supplying to the common DC grid, such as fuel cells, solar panels, high speed generators, wind turbines etc.

- Significant reduction in space and weight of installations - Lower energy losses and a less complicated conversion system could potentially translate into lower maintenance requirements and lower operating cost

- Easy to utilise possible braking power without any additional components like breaking resistors or regenerative bridges.

- Improvements in engine efficiency since engine speed can be optimised according to load - Possible to use common energy storages for stabilising the power generation - Higher power distribution capacity e.g. if 1000VDC is used instead of 690VAC due to lower current and avoiding reactive current and inductive losses.

- Increased voltage quality for sensitive loads than is the case in todayâ&#x20AC;&#x2122;s systems - Easy to compensate voltage losses without disadvantages, keeping rated DC voltage a bit

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Figure 3: A matrix DC electric power plant with fixed DC voltage ECI.

higher than is needed for inverters to create necessary AC voltage for consumption.

- In practice, current standards allow using higher voltage ratings in DC than in AC in a low voltage installation in some ranges (1000VAC and 1500VDC) - No inrush and starting currents affecting system stability - Allow the use of buck- and boost converters for DC loads like water heaters - Easier and cheaper to implement different UPS systems - Can be connected for both 50HZ and 60HZ shore connection via same simple diode bridge

The components for such configurations are in principle already available today, but their adoption would not be without challenges, both of a technical and rules compliance nature. To start with, consider Classification Rules; new definitions on main switchboard and protection would have to be made, as the present rules are focused on AC distribution systems.

Other issues to be addressed would be: - Control of load sharing must be achieved using other means than the speed governor - Supply to ship auxiliary AC loads would need to meet class requirements for AC distribution - Selectivity in protection, as mechanical DC circuit breakers are infeasible for high fault currents

conclusion In conclusion, then, the solution used for electric power generation and distribution today has significant advantages when compared to convention-

al solutions. However, it also places some restrictions on how to optimise the design with respect to space and weight, and how to optimise operations with respect to fuel efficiency. It also limits the possibility to utilise alternate power sources.

It has been shown, however, that it is technically feasible to design the power plant by using new design methods, which are based on technologies that already exist today. These methods promise remarkable savings in space, operational cost, fuel consumption and emissions. However, to achieve these objectives, further technical development and the rewriting of classification rules and regulations will be necessary.

Two alternative solutions to the common AC grid distribution system have been described; but they can well be combined in the same installation if found feasible.

Even though such distribution systems do not exist today, and rules and regulations do not describe the required features for such, it is not an Utopian concept. Developments are needed, but the basic building blocks are already existing in standard industrial products. |||

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matrix dc distribution The matrix DC distribution system is based on the concept similar to the common grid DC distribution, where the ECI requirements could be the same and still achieve all the benefits previously mentioned. However, the idea is to provide a complete segregation of each of the power sources, or a group of sources; here, faults in any point of the distribution system can only affect one source (or group of sources).

This could be achieved by a matrix supply system, where each essential consumer, like propulsion or thruster, is multiply supplied from several sources in a matrix network, Figure 3.

One advantage of common grid DC distribution (easy to adapt multiple and various sources of electrical energy supplying to the common DC grid) can easily be further utilised through the matrix DC distribution optimising the use of different power sources based on availability and a prevailing production cost of each individual energy source installed in the system. Simply, power is supplied from the most economical available source (diesel engine, energy storage, fuel cells, solar panel etc.) based on the power requirements of each consumer.

The matrix distribution system can be built using cabling so that only the other ends of parallel cables are connected to a different â&#x20AC;&#x153;source panelâ&#x20AC;? instead of being connected to a common circuit breaker, as in AC distrbution. Thus, the amount of cabling can be almost the same as in other configurations. Different level of independence between power sources can be achieved depending how the used power source has been arranged in the consumption end. Another way to arrange the matrix distribution would be using the DC bus bar systems in such a way that each power source group has its own bus bars to which the consumers are connected. In this approach, the bus bars can be routed through the ship, having full segregation between them. For example, if there are three separate power source groups, as in figure 3, two of the bus bars can be mounted in the side of the ship and one in the middle.

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Blackout prevention and recovery Reducing the potential for blackout has proved a critical development in the wider application of shipboard electric propulsion systems. Dr. Jan Fredrik Hansen and Dr. Alf Kåre Ådnanes, of ABB Marine, Norway, explain. author:

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Jan Fredrik Hansen ||| Alf Kåre Ådnanes

for dp vessels and drilling rigs, a total loss of electric power is obviously one of the most severe failures that can occur, where all electric systems are lost unless powered by battery back-up, and thrusters driven by electric motors are unavailable for station keeping.

Blackout is therefore a condition to be avoided by all practical means, and should it still occur, the restoration the power plant should be reliable and within an adequate time. The term “adequate time” is used since this does not necessarily mean “as fast as possible”; different vessel and their operational requirements influence the targeted recovery time. With an “as fast as possible” approach, systems will become more complex to operate, using additional components and functionalities with new failure modes, and hence the required start up time must be considered during the design, without compromising the overall safety of operations.

Prevention of black-out and the availability of electric power is essential for ships with electric propulsion and for DP vessels in particular.

As any man-made technical system will sooner or later inevitably fail, efforts must made to minimise the likelihood of failure through proper design, monitoring, and maintenance. At least equally important, however, is minimising the consequences of failures. The starting point for a reliable and available electrical power plant is to use proper and proven engineering methods in the design and engineering phase, in particular with respect to analysis of any possible faults.

Analysis of actual incidents from operations gives a valuable insight in the real causes of black-out and other undesired behaviour, which should be used when deciding where the main efforts should be made in order to gain the best levels of safety. Although some data bases of incidents exist, they are to some extent inadequate, due to lack of reporting and insufficient detail on root causes. Statistics from Petrobras presented in 2005 categorised the root causes for black-out incidents as follows; - Human error - Protection system

Figure 1: Root causes for black-out, data from Petrobras1.

- Fail / lack of maintenance - Project and commissioning - Lack of procedure The statistics were gathered from 1992 to 2004 and the distribution of the root causes were shown as a total over the 13-years period, and then for the last 5-year period, as shown in Figure 1. In this 5 year period, several of the drilling vessels being built in the late 90’s were put into operation, concurrent with DP vessels of earlier origin.

Although the statistical material is limited – 43 incidents in total, and 24 incidents in the last 5 years –, some conclusions can be drawn. The most significant one is the conspicuous increase in the share of root causes traced to human error; while more technical reasons showed some slight reduction in trend terms, most obviously those related to the protection system.

Likely to be contributing to this positive trend on the technical side is the introduction of newer vessels, such as 5th generation drilling rigs, with a new generation of variable speed thruster and drilling drives with far better characteristics than the fixed speed or current source inverter drive thruster drives and DC drilling drives that were state-of-the-art during the late 80’s and early 90’s. In particular, the technology transfer to the use of VSI (voltage source inverter) technology was

a leap forward in terms of optimising power plant and enhancing black-out prevention performance.

Furthermore, during the 90’s more sophisticated electric power system protection systems and blackout prevention functionalities were implemented in marine electric systems. Digital, multifunction protection systems that have been most recently offer more advanced and compound protection functionalities than was possible only a few short years ago.

On the other hand, although more recently developed electrical power plants are more reliable than ever before, each incident is one too many; and further efforts to enhance the reliability of the power plant are needed and also achievable. power management and load reduction The power management system is essential in providing optimal and safe operation in electric power plant and diesel engines. It ensures that sufficient power is available for the intended operations, and at the same time optimises the power plant for reduced fuel consumption, thereby achieving better operational economy and reduced environmental emissions.

One of the critical functions in the power management system is the load reduction function. This not only provides a function for avoiding overload of

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Figure 2: Typical curve for a diesel engine driven generator; showing the inherent capability of the diesel engine driven generators to provide sudden load steps before driving into under frequency.

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Figure 3: The load and frequency behavior after sudden trip of engines in a vessel with electric propulsion. Load reduction in the propulsion control ensured that the network frequency kept well within the operational constraints.

the power plant by increasing load demands of the thrusters and other loads â&#x20AC;&#x201C; it also provides fast load reduction for power controlled consumers, such as the thrusters, in the event of a sudden loss of power generator capacity, should a a diesel engine stop.

Such fast-acting load reduction systems have been shown to be challenging to include within power management systems, since the required time response is short. Figure 2 shows a typical system, and how the capability of a diesel-generator set has to accommodate sudden steps in loads. The physics behind these curves is based on the fact that the governor of the diesel engines cannot act fast enough to prevent the initial drop in speed when the load increases suddenly, as will happen in the case of a healthy diesel engine upon a trip of an engine that is operating in parallel and feeding into the same electric power plant. During the first instant after the trip of the paralleled engine, the load increase must be supplied by

the inertia of the other diesel engine and the generator, as well as by other rotating loads in the network.

As can be seen, using fixed speed controllable pitch propeller (CPP) thrusters, as was commonly the case in the early 90â&#x20AC;&#x2122;s, the time to control the load was unacceptably long, and the only way to prevent black-out was to shed the thrusters from the network, leading to a loss of positioning capability and capacity. Also, the load reduction that is a requirement for DP control system is far too slow to avoid black-out in situations with sudden loss of generator capacity.

The load reduction of power management may, if made fast-acting and event-based, can give a response time that is short enough to prevent most overload scenarios. However, it has been observed that, even in the case of relatively new power management control systems, it takes up to 1000ms after the event before the actual load reduction signal is issued.

Normally, a maximum pf 300ms is a requirement,

est engine was exposed to nominally 3x peak power over a short period of time. As is shown, the load was reduced quickly enough to keep the frequency of the network well within the operational limits (+/-10%). In this particular case, the generator incomer breakers to the main switchboard were monitored.

A traditional marine power system for mobile offshore units consists of power generation, power distribution, and variable speed thruster drives as the main parts of the vessel electric power and propulsion systems. In addition, each vessel type has certain power consumers corresponding to its operational characteristics, e.g. drilling equipment on drill ships/rigs.

Power generation is the most essential part in these â&#x20AC;&#x153;all-electricâ&#x20AC;? vessel concepts. Even though it usually consists of several generating units, these are most commonly operated in parallel and electrically connected via the main switchboard. The worst case scenario is when a single failure leads to a total blackout of the power system.

The most obvious and common way to avoid this kind of situation is to split the power plant into several independent units. This is routinely incorporated in the design, usually as 3 or 4 split configurations for drilling vessels, with the additional possibility to operate with closed bus breakers. The advantage of operating in the closed breaker condition is that it is possible to optimise power loading of the running generators in order to consume as little fuel as possible. However, this has not been allowed for the most severe DP operations in harsh weather conditions or in general for operation with DP class 3.

Protection of the power plant against the most severe electrical failure conditions is achieved by protecting relays which continuously monitor the voltage and current at each feeder or incomer in the switchboards. These relays disconnect equipment exposed to electrical failures as a short circuit, over current, abnormal voltages, etc, in order to avoid/minimise component damages. Even though the relay settings are made in a selective way to minimise the affected area, there are no guarantees that the relays will not trip the whole production plant in certain failures. The root causes for such trip and disconnections may be

Figure 4: DGMS cabinet with standard dimension of 830 x 410 x 1140mm (LxWxH)

meaning that the frequency converter of the variable speed thruster drives must have built-in monitoring of the power plant, either by monitoring the network frequency or the generator circuit breakers, in order to achieve a sufficiently fast-acting black-out preventing load reduction.

Such functionality has now become common in ABBâ&#x20AC;&#x2122;s thruster and propulsion control systems, and proven in tests to give ultra fast response times, and even with high step loads of the power plant and excessive overload of the healthy engines, power demand can be reduced quickly enough to avoid intolerable frequency drops.

Figure 3 shows the results from a vessel with electric propulsion, and the behaviour of the system frequency upon trip by one of its four dual fuel engines.

It must also be noted that the three first engines to be stopped had a rating of twice that of the last engine to be on-line, meaning that the last and small-

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diesel generator monitoring system

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Figure 5: Interface schematic for the DGMS and related equipment.

difficult to discover, as they may differ from the direct cause of the trip (current, voltage or frequency out of safe operation range).

The Diesel Generator Monitoring System (DGMS) from ABB is designed to detect such failures that are not directly detected by the protection relays. The main purpose for the DGMS is to issue an alarm, enabling the operator to take protective action before a blackout situation occurs, and in the most extreme case, isolate and trip the faulty generator set.

ABB introduced DGMS as additional generator monitoring in 2003, and it was installed on the pipe layer Sunrise 2000 in 2004. This first installation was a tailor-made product in terms of the vesselâ&#x20AC;&#x2122;s electrical particulars.

Themodular version of the DGMS has been designed for use on power systems including up to 8 generators and 8 switchboard splits. The basic concept is to install one cabinet per installed generator.

Each cabinet consists of an AC800 PLC, with corresponding I/O modules, power supply, etc. Figure 4

shows an example of the wall mountable cabinet.

Each cabinet interfaces with the generator, Automatic Voltage Regulator (AVR), switchboard, engine and governor, as shown in Figure 5.

In addition it is possible to connect each DGMS cabinet to each other via an Ethernet ring for data sharing. This feature is required for systems operating in isochronous speed mode where data sharing is necessary to detect which of the generator sets are running with faulty conditions. This feature can be disabled on systems where only speed droop operations mode is used.

The functionality of the DGMS extends that of the normal protection functions from the relays. The DGMS does not interfere with these; hence any failure of the DGMS itself will not introduce reduced performance compared to the traditional design without DGMS. This add-on functionality also makes this product suitable for installation on existing vessels for the functional upgrade of the power generation protection and monitoring system.

The following failures are detected by the DGMS that are not detected by standard protection relays: - Over/Under fuelling by comparing the system frequency and generator active power to expected behavior in current operation mode.

- Over/Under excitation by comparing the system voltage and generator reactive power to expected behaviour in current operation mode. fast restart after blackout In the unlikely event of a blackout, it is also important that the system is designed to recover as quickly as possible. The traditional way to handle this is for all available generators to receive a start signal, with the first one up and running connecting to the dead bus. As soon as the bus

Figure 6: Schematic diagram of converter charging topology.

is live the process of restoring the loads is started. For variable speed thruster drives this implies starting all auxiliaries, such as cooling pumps and fans, lubrication pumps etc., and charging the DC link in the frequency converter. This has been done in a sequential way until now, with the result that the restart process may take up to several minutes.

With relatively small and simple adjustments of the equipment and philosophy, it is possible to reduce this starting time by parallel processing. For the ABB ACS 6000 converter, the following upgrades are now available: - Hot standby feature during main and auxiliary supply interruption, e.g blackout - Standby time up to 10min without auxiliary supply feeding the water cooling unit - During standby, the converter remains energised enabling restart of the drive with minimum delay after main and auxiliary supply is restored in the power network.

- Available as an in-built feature for new deliveries or as an upgrade kit for already delivered and operating converters.

- Autonomous thruster system restarts control functionality within the drive control unit (optional).

blackout prevention and recovery

The design philosophy includes the following features: - Detect failures - Create alarm - Start standby diesel engines - Isolate faulty engine before blackout condition occur (only when the system is crossing pre-set trip limits) - Isolate faulty switchboard section (only if isolation of faulty engine fails)

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!

Figure 7: Typical thruster restart sequence after blackout for standard ABB drilling vessel application

Figure 6 shows the details of the converter charging topology, with the modified sections rendered in blue.

The following modifications are undertaken: Charging Circuit - Backup charging branch fed from UPS powered control voltage supply maintaining intermediate dc-link voltage level during power interruption - Charging transformer with additional tapping for back-up charging supply DC Intermediate Circuit - Air cooled balancing resistors withstanding water flow interruption.

Software - Additional functions for supervision and control supporting (new feature).

appr. 6s for a typical drillship application. However, this is highly dependent on the rotor time being constant to determine the motor magnetization time.

- Auxiliary and steering pump is restarted simultaneously with the thruster converter and the restart time is assumed to be within the converter restart time (to be verified with the IAS, thruster and auxiliary system supplier).

- Optional: Thruster converter, auxiliary and steering restart is autonomously controlled in the Drive Control Unit (DCU).

See Figure 7 for a block diagram representation of the starting sequence.

In the event of a blackout, the power plant should restore itself automatically. The configuration of the power plant after restoration must be carefully determined to ensure available power to thrusters and other essential loads, but avoid entering into a potential new fault condition.

Typically, blackout restoration is controlled by the vessel management system, using a logical sequence of events leading to start-up and synchronisation of diesel engines and generators, and the connection of auxiliaries and essential loads. It is essential that this blackout restoration

As a consequence of these modifications the converter can be kept charged for up to 10 minutes during a blackout, without any auxiliaries running. Furthermore, the starting sequence can be described as follows: - Blackout/power interruption shorter than 3s, covered by Ride-Through and the under-voltage function in the drive, with no restart required.

- Blackout/power interruption longer than 3s, restart time after power restored in the network

safe operation regardless of how many automatied systems are used, and it is therefore important to keep the system simple and thereby intuitive for the crew to operate in safe manner when needed.

With additional generator protection, such as the diesel engine monitoring system (DGMS), the risk for blackout can be reduced. This product adds on to the standard protection relays, without interrupting the relay functionalities. By comparing several variables from the diesel generator set with normal operating curves, it is possible to detect failures that are emerging in the engine or generator control system before it would be detected and tripped by the protection relays. The DGMS is also suitable for retrofit on existing vessels.

With usage of the fast restart modifications of the ACS 6000 converters, it is possible to reduce the thruster restart time to 6s after the voltage is restored on the main switchboard. ||| references

1. Pallaoro, A.A.: DPPS â&#x20AC;&#x201C; A Petrobras DP Safety Program; Keynote Speech DPC 2005.

blackout prevention and recovery

time sequence is thorough in relation to the suppliers involved to avoid both unnecessary time delays, but also to ensure that the start-up performs with high reliability and without failures from exceeding the operating limits of the system and the equipment.

The use of battery backed-up supplies for essential auxiliaries and control systems, may reduce the start-up time. It should, however, be noted, that the more equipment and systems being installed that the start-up sequence is dependent on, the higher is the risk of failures that could not be detected during normal conditions. This is particularly important if the additional systems are not active during normal operations.

The need for monitoring and fault detection increases as complexity increases, and for practical solutions there must be a balance between what is the required performance and the system complexity necessary to achieve acceptable performance. If the system can be recovered within the time required, a simpler solution with less likelihood of failure may be preferable.

As the solutions will reflect the requirement for each vessel, it is necessary to address these in the early specification phase of the functionality of the installation, involving all parties involved in cross-discipline functional integration. in general, as time has passed, electric power plants have become more reliable and have come to experience fewer blackouts. This has been achieved by better protection systems, and the wider use of variable speed thruster drives with VSI technology that was introduced in the 5th generation DP drilling vessels in the end of the 90â&#x20AC;&#x2122;s. Further improvements were introduced later, via digital protection relays and programmable controllers to implement more sophisticated protection functions.

However, there is still potential for improving systems, and a continuous effort to enhance the availability of the power plant and reduce the restoration time is necessary. Although this should not necessarily be done by replacing proven systems with completely new topologies, but rather by a focused effort to improve within the areas where experience and operational statistics show the greatest potential for improvement. Available statistics indicate that the human factor is the greatest contributing effect to undesired incidents. A human interaction is necessary for

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Deepwater pipelayer and heavy lift crane vessel from abb China’s main execution center for marine ABB Marine China has become one of five Main Execution Centers (MEC) in Marine, fully responsible for ABB’s Marine business in China and World Wide technical responsible for Heavy Lift Crane Vessels and Dredgers. author:

Roar Nyheim – roar.nyheim@cn.abb.com ||| David-BingHui Li – david-binghui.li@cn.abb.com

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Figure 1: Artist’s impression of the pipe layer and heavy lift vessel.

one of the projects now being executed is the new Deepwater Pipelayer and Heavy Lift Crane Vessel for Offshore Oil Engineering Co. Ltd (COOEC), Figure 1.

The vessel has been designed by Shanghai Merchant Ship Design and Research Institute (SDARI), and construction is ongoing at Jiangsu Rongsheng Heavy Industries Group Co., Ltd. Shipyard.

The vessel is designed for pipe laying speed of 5 km/day in water depth of up to 2000 m, primarily in the East China Sea, South China Sea and south East Asia Sea.

system overview The vessel will have DP class 3 in crane safe condition mode and DP class 2 in pipelayer condition modes; and shall be classification by both ABS and CCS.

ABB has been awarded the contract for a fully electrical package comprising 6.6 kV power generation and distribution System, and the variable speed electric drives for the main propulsion and retractable thrusters.

The electric power system, Figure 2, consists of totally six 6.6 kV diesel engine driven main generators supplying two 6.6KV Main Switchboards connected together via transfer breakers and a change-over switchboard. The change-over switchboard is supplied via outgoing feeders from both main switchboard no.1 and/or no.2. Each main switchboard are supplied with bus-tie for dividing the switchboard into two sections, and the normally operation is with closed busties. The three main switchboards are connected to allow maximum power and optimal loading of the diesel

G G

AC AC AC AC M

Ballast pump

M

Main Azi. Thr.

G G

M M

Ballast pump

To Crane

To Crane

M

Ballast Main Azi. Thr. pump

Retr. Azi. Thr.

AC AC AC AC

M

AC AC AC AC

AC AC AC AC

M

M

G G

AC AC AC AC

AC AC AC AC

AC AC AC AC M

G G

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Ballast pump

Retr. Azi. Thr. Retr. Azi. Thr.

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Retr. Azi. Thr.

Figure 2: Single line diagram

engines, ensuring the best fuel economy with respect to the connected load.

The 6.6 kV switchboards are of type ABB UniGear ZS1 and are produced by ABB Xiamen switchgear Co., Ltd. in Xiamen, China by the specification of ABBâ&#x20AC;&#x2122;s main execution center for Marine; as the marine and classification societiesâ&#x20AC;&#x2122; requirements differs significantly from most other industrial application, with stringent technical and functional specifications, Figure 2.

For DP requirements and station keeping capability, the power system is configured to allow for five out of six main generators and six out of seven thrusters to be able to run after a DP class 2 single failure of the system, as well as it provides the power to the other consumers connected to the distribution system. If a fault occurs, bus-tie and transfer circuit breaker will automatically open and isolate the faulty bus before reconnecting the system for maximum flexibility in all operational modes. In case of bus-bar faults such as e.g. short circuit the protective devices will open the dedicated bus transfer to split up the distribution system into two separate systems.

electric variable speed drives for propulsion and positioning thrusters When controlling the thrusters with electrical variable speed drives, the dynamic performance and maneuvering characteristics is significantly improved. Operational flexibility and improved hydrodynamic efficiency when compared to controllable pitch propellers gives low fuel consumption, reduced maintenance costs, less environmental emissions; and also eases the efforts to obtain an adequate redundancy with less installed generator capacity. thruster control The thrusters are driven by electric motors controlled by variable speed thruster drives with, each with a separate Drive Control Unit (DCU).

The drives are fed from the switchboard through the three-winding propulsion transformers. A load dependent number of running diesel engine generator sets, being controlled by the power management system, supply electrical power to the main switchboard to which all consumers are connected. One of these consumers is the system of electric propulsion and thrust-

deepwater pipelayer

G G

G G

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Figure 3: ABB ZS1 UniGear 6.6kV switchboard, specified for marine requirements.

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Project information

ers. In most cases, the electric propulsion and thruster system is the largest consumer of power. The electric thruster system consists of the above explained power plant, thruster motor, variable speed drives comprising transformers and frequency converters connected to the main distribution switchboard, remote control system, thruster control system, auxiliary systems, and optionally diagnostics system.

The propulsion control system consists of dedicated application controllers, I/O stations, field buses and software. The propulsion control software run by programmable application controller(s) is based on standard scalable and configurable software. The propulsion control software provides functions to control, protect, and supervise the propulsion system.

The propulsion control software also includes power limitation functions to prevent overload of the supply network.

Ship Owner: Offshore Oil Engineering Co. Ltd (COOEC) Ship yard: Jiangsu Rongsheng Heavy Industries Group Co., Ltd. Ship Designer: Shanghai Merchant Ship Design and Research Institute (SDARI) Classification: ABS and CCS Estimated vessel delivery date: June 30th, 2010

abb scope of supply 6 x 7.2 MVA Main Generators 3 x 6.6 kV Switchboards 2 x 6 MVA Main Propulsion Transformers 5 x 4 MVA Thrusters Transformers 4 x 4 MVA Distribution Transformers 2 x 7 MVA Main Propulsion Frequency Converters 5 x 5 MVA Thruster Frequency Converters 2 x 4.5 MW Main Propulsion Motors 5 x 3.2 MW Thrusters Motors 6 x Neutral Point Resistors 2 x DC-UPS for MV Switchboards 2 x AC-UPS for Drive and Drive Control Units 7 x Drive Control Units for Main Propulsion and Thrusters

The Marine in China was established in Shanghai already in 2002, aiming to serve customers locally by a dedicated Chinese organization. Today Marine China has become one of five ABB Marine’s Main Execution Centers, fully responsible for ABB’s Marine business in China.

This has been widely recognized, not only by domestic ship owners and builders, but also by other shipping companies building vessels in Chinese yards.

A typical project consists of the following services, in addition to the manufacturing of products: – Project management, responsible for the delivery – Project engineering, responsible for analysis and studies, function descriptions, technical specifications, and drawings needed for construction – Coordination of design and Interfaces with ship owner, ship yard, design institute and suppliers – Data for the classification society that is needed for classification of deliverables – Logistics and transportation – Commissioning services – Training for end user ||| project execution

Azipod® XO – steering to success What happens when ABB Marine’s engineers, specialists from sourcing and manufacturing, yards and end users get together to develop the Next Generation Azipod propulsion system? The answer is; real innovations for the future at sea! Lauri Tiainen, Azipod® product manager, explains.

Lauri Tiainen – lauri.tiainen@fi.abb.com

started some 20 years ago and the product has been modified step by step and improved while gaining a position as a major propulsion system for luxury cruise ships and ice going tonnage. However, in principle, Azipod has been based on the same main ideas and solutions as was the case with the first prototypes.

In order to develop a completely new Azipod generation, a comprehensive development programme was started within ABB Marine in January 2006. Based on over 4.5 million Azipod operational hours gained through the years, this development programme fundamentally challenged all of the earlier chosen solutions and took a fresh approach to the mission, not only from technical point of view but also

the development of azipod propulsion system

Azipod Interface Unit - AIU

Local back-up Unit - LBU

from the viewpoint of safety, maintainability, reliability, production, human interface, life cycle cost, environmental features and overall design. Customers gave important input in selecting the right solutions from a wide variety of possible alternative configurations.

Innovation does not pop out of the bush and say “hello, here I am!”. Real innovation is the result of the continuous evaluation of new ideas and possibilities. Tens and hundreds of ideas are needed to discover the real innovation behind the most obvious solutions. This was the way it went during the development of the Next Generation Azipod.

Evaluation of ideas and further development were achieved in very close operation with several yards innovations inside

Steering Drives - SD

Shaftline support unit - SSU

Cooling air unit - CAU Slipring unit - SRU AD-in Steering module AD-out Propulsion module Figure 1: Innovations are inside the Azipod XO®

azipod xo

author:

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Figure 2: Interspace shaft seal arrangement makes it possible to maintain seals inside the Azipod XO

Azipod® XO – innovations inside

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– Improved efficiency: less is more – Interspace: revolutionary shaft seal system – Hybrid bearing: thrust to your business – Easy access to the Azipod: safety first – Advanced condition monitoring for preventive maintenance – Fully electric steering system for redundancy, environment and comfort – Maintenance friendly steering module – Intelligent bridge control interface for efficient operation practices – Modular design targeted to varying customer requirements

and end users. After all, it was concluded that good ideas do not become true innovation without direct customer feedback!

Even if, on the face of it, the Next Generation Azipod (now branded Azipod XO®) looks quite conventional, new innovations are to be found on the inside.

Podded propulsion has already been proven as improving hydrodynamic efficiency compared to conventional electric shaft line systems by about 10 to 15 %, depending on ship type and operation. However, the project team was encouraged to put their efforts to investigate the possibilities for reducing energy consumption further, and thus also the CO2 emissions of the vessel.

Being a complex product with many different considerations to be borne in mind, such as maintainability, ship installation and cost, hydrodynamic design

has its limitations, and compromises have to be made with respect to different design features. Roughly 15 different new hydrodynamic shapes were developed and analysed with CFD (Computational Fluid Dynamics). Again, many test sessions were held at a model basin to verify the practicality of new ideas. Finally, a definitive shape was selected for the new Azipod.

For the outsider, the new hull looks quite the same shape as was the case for the previous generation.

However, the propeller hub and Azipod hull diameters have been reduced and Azipod strut shape has been further optimized. This new shape brings with it about a 2 per cent improvement in hydrodynamic efficiency in a tested case. This might sound like a minor matter but, for a typical cruise ship, it means a half a million Euro savings per year, on top of the 10-15% efficiency saving already achieved over conventional propulsion. interspace

– revolutionary shaft seal system

One example of an open minded and innovative solution that has been adopted is the new sealing system for the propeller shaft. It is easy to imagine that, if sea water leaks inside the pod and into the high power electric motor, the leakage most will most probably cause costly harm to equipment and and bring about time consuming dry-docking to repair the motor. At least as important, from the environmental perspective, is that lubricants from the bearing do not leak into the sea.

The interspace concept is a really revolutionary innovation (patent pending). This concept makes seal maintenance possible inside the Azipod and gives the ship operator a huge advantage minimising risk in operation. With a designed-in redundant temporary seal arrangement, all seal rings can be changed. This arrangement also divides seal packages for water and oil seals, meaning that it is just not possible for water to leak into the bearing or for bearing oil to leak into the sea.

The seal against the water is equipped with an active system that controls the seal’s operational environment and optimises its condition for an extended lifetime. For example, the balance between pressure and heat is automatically optimised. The system also enables advanced condition monitoring to a degree not seen in the market.

hybrid bearing

– thrust to your business

Figure 3: Hybrid bearing offers new possibilities for life cycle management

Figure 4: Advanced propulsion condition management system – important tool for life cycle management

easy access to the azipod – safety first Special attention in the design has been paid to human safety during installation, operation and maintenance of the product, e.g. safety when moving about inside the Azipod hull during maintenance. Also for safety reasons, the interior of the Azipod hull has been made as spacious as possible, while special ‘Azigear’ work gear has been developed for maintenance personnel needing to work in confined spaces. Together with AziGear, permanent ladders, safety rails and better lighting increase the safety level of working inside an Azipod safety significantly. advanced condition monitoring Today, preventive maintenance and predictability of maintenance are getting more and more important in the shipping industry. To meet future needs, Azipod XO was designed to include a very advanced propulsion condition monitoring system (PCMS). PCMS monitors most vital parts of the whole propulsion system; from propulsion drives to the Azipod bearings. This system collects data from multiple sources, processes it and produces easily understandable graphics of the system’s status for the crew to follow up. For example, bearing temperatures and vibrations, oil contamination and propulsion motor temperatures are all monitored.

In addition to that, the system enables remote diagnostic services: for land-based monitoring by the customer and/or ABB. The PCMS is a very useful tool for life cycle management and for trouble shooting.

Azipod XO

The hybrid bearing (patent pending) is in principle a very simple bearing arrangement. It combines two different known bearing technologies: the slide and roller types. Nevertheless, the combination is new to the market. Radial support of the shaft line is achieved using well proven roller bearings. The thrust bearing is of the slide type and carries all thrust loads of the propeller in both forward and backward directions. Thrust pads are of the white metal type and it is possible to change them from inside the Azipod. This innovation gives the ship operator a significant benefit; submit to an extended dry-docking interval of thrust bearing maintenance, when this can be done at sea?

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Azipod XO steering is fully electric, instead of the earlier hydraulic solution. This new system brings with it such benefits as easier installation, improved efficiency, reduced need for maintenance and less noise. The small amount of oil needed is also an important factor.

The basic electric steering principle is to control steering motor speed and rotation direction with frequency converters. Each motor has its own steering drive which yields redundancy advantages, because any single failure does not reduce available steering capability. Steering motor power is transferred through the reduction gear to the pinion and on to the gear rim, which is rotating the Azipod. The system is controlled by an Electric Steering Control Unit (ESCU), which includes the intelligence of the system. The location of the steering drives and ESCU can be selected in a flexible way that is advantageous to the yard when designing machinery spaces.

The slewing bearing, located inside the steering module, is one of the most vital components in the Azipod system; it carries all loads from the propulsion module. Therefore, slewing sealing, which prevents water entering the bearing, is a very important part of the system. Naturally, seals are wearing parts and that fully electric steering system

Azipod XO

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is taken into special consideration in the Azipod XO steering module design.

Azipod XO slewing seals can be changed from underneath the ship’s hull with relative ease; even afloat, depending on the ship’s water line. In addition, there is an air actuated emergency seal for risk management.

This seal can be activated at a very early stage when system indicates that leakages have started. This emergency seal allows normal operation to carry on for extended periods, giving the operator the breathing space to plan the next maintenance work.

Even if the slewing bearing is designed with a very long life in mind, it may have to be changed on occasion. For this reason maintenance friendliness has also been considered here, with the slewinbg bearing positioned so that it can be changed on the ship’s side, in order that there is no need for major operations inside the ship.

Freely 360° rotatable podded propulsion is a fantastic tool for ship handling. Nevertheless, there are also some drawbacks. With very powerful devices, it is possible to harm other devices or use too much power and additional fuel if the deck officer is unaware intelligent bridge control interface

Figure 5: Maintenance friendliness is targeted for Azipod XO’s steering module

Steering gear rim

Slewing bearing

Slewing seal

Azipod XO

Figure 6: Azipod XO intelligent bridge control interface main screen

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of what is happening under the ship‘s stern. It is understandable that a ship of 300m length or more does not necessarily give the helmsman a “feeling” as to what is happening at its other end. For this reason, the Azipod XO intelligent bridge control interface has been developed.

The Intelligent bridge control interface is the part of the system for steering and moving the ship – maybe the most important system in the whole ship. Improvements in this new system are: - only the most important information is presented on the main screen - indication of fuel economy is presented - recommended and not recommended steering angles are presented to minimise unnecessary loads to other Azipods as well as cavitation - status of the system vibrations are presented - data history is stored in the system for deck officers’ self training – where did I do it right and where do I have something to improve - available power plant capacity is presented - command and actual steering angles as well as thrust are presented

- individual and combined force vectors of two or more Azipods are presented - the system is built up as a modular construction to make it easy to install it as a part of the other bridge systems - Field bus based – less cabling for easy installation The intelligent bridge control interface improves usability of the Azipod system and enables operator to minimise the life cycle cost of the ship.

The experience of first generation Azipod units has been that the product has to be of modular construction. This philosophy has a lot of benefits: by standardization, the product quality is improved and manufacturing is simplified. However, it is essential that the modular, standard solutions, and alternative solutions and available options, are selected in a clever way. The Azipod XO product family is made up of roughly 300 modules and some tens of optional modules. With a product “pallet” like this, a fast and reliable response to varying customer requirements is ensured. |||

CRP Azipod® design author:

Tommi Veikonheimo – tomi.veikonheimo@fi.abb.com

since 2000 abb has spent lots of resources to the research and development of CRP Azipod propulsion system. It started with efficiency gain determination project for RoPax ferry. Since that manoeuvring, performance, cavitation, CFD techniques and strength evaluations have been studied. All fields of hydrodynamics are covered. In these above mentioned projects we have had several partners like Samsung Heavy Industries, Mitsubishi Heavy Industries, NYK, Akeryards, Wärtsilä, DSME that have given important contribution to the development task. One successful full scale application has been built sofar for ShinNihonkai Ferries at MHI shipyard in Nagasaki (Fig. 1).

main characteristics of crp azipod system This propulsion system is a combination of two separate propulsion systems which are coupled together in co-axial arrangement. Directly behind conventional main propeller (CPP or FPP) which is directly or via gear coupled to the main engine(s) is Azipod unit with electrical motor inside. The complicated shaft systems with two propeller driving shaft inside each other can be avoided. The propellers are turning opposite directions forming a CRP system with high efficiency. This arrangement gives possibility to replace the conventional rudder with pod unit still keeping the conventional single screw hull lines unchanged (only

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Figure 1: First CRP Azipod ship in drydock

suitable ship types The improvement of propulsive efficiency compared to single or twin screw vessel is dependent of the loading and ship speed of each individual project. If the vessel has a propeller(s) that is designed to smooth wake field with optimum loading and propeller diameter is optimum for given RPM, the gain in total propulsion efficiency will be small even marginal. In this kind of ships CRP Azipod system is not selected from efficiency point of view but in these cases the benefits of CRP may be found somewhere

crp azipod

local modifications needed) and benefit from the good performance of the single screw hull form (resistance, hull efficiency).

CRP Azipod system is best suitable for ships that have high forward speed and high loading on the propellers. In these ships the propeller loading can be significantly reduced thus gain in efficiency may be achieved. Also the forward propeller rotational energy component is more pronounced in this kind of ships thus there is more energy saving to be recovered.

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Figure 2: A large container vessel with CRP Azipod in model scale

Figure 3: Forward propeller effective wake field calculated with CFD.

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else for example in improved harbour manoeuvring, redundancy, reduced machinery spaces or low noise and vibration level. Because there is several aspects and possibilities in CRP Azipod system the suitability and benefits for each project has to be considered separately in each project.

The most favourable cases or projects for CRP Azipod systems are those where the loading of the propeller with conventional system is very high due to the high ship speed or restricted possibility to install larger propeller. The possible ship types are fast RoPax vessels, ultra large container vessels, LNG carriers, car carriers.

ABB has done R&D studies for several ship types in order to clarify possible efficiency gains for CRP Azipod system. Most favourable results has been reached in Ropax vessel projects where efficiency gains from 12 â&#x20AC;Ś 20% are achieved. Best example is Shin-Nihonkai Ferries project where 20% saving in fuel consumption has been reported. Other ship typed has been studied as well. For example our co-operation project with Samsung heavy industries with large container vessel showed 5% improvement in total propulsive efficiency against single screw propulsion and 9% improvement against twin skeg propulsion.

This propulsion system has four main components from which ship hull and pod hull are considered as passive in detail design phase.

Both propellers are then treated as active components of the system. Azipod unit is not really passive because it is acting in operation of the vessel as steering device, but in propeller design process it is treated as passive component like ship hull in front of forward propeller.

There are two inflow fields or wake fields to be considered in this system. First one is the flow field towards forward propeller. This wake field includes all characteristics that ship hull creates to the flow. The flow is three dimensional and it is decelerated due to ship hull and boundary layer effect. If this wake field is taken as it is without propeller interaction effects it is called nominal wake field. Nominal wake field is very much different compared to effective wake field which includes acceleration of flow close to propeller disc in front of forward propeller. For example flow separation seen in nominal wake field might be absent in system components

Figure 4: Wake field at after propeller disc calculated with CFD.

Figure 5: Example of detailed geometry grid of CFD computation

determination of propeller design conditions

In model scale measurement of nominal 3-D wake field without propellers is possible. Effective wake field may be calculated to full scale from nominal wake measurement with different methods but accuracy is questionable.

ABB is confident that new method needs to be utilized now in order to achieve better and more accurate results. CFD is a tool that gives more detailed answers to designer of the flow around this complex propulsion system. Model testing can give answers to whole performance but fails to give insight to details that are sometimes very important. In our research programs full viscous RANSE calculations have been performed and especially more extensive information about the flow and interaction between two counterrotating propellers is obtained. This detail information has helped to design more efficient propellers.

Figure 6: Azipod hull and two computational rotating drums that include the propellers inside

CFD has become more and more important tool when this kind of complex propulsion systems are designed. CFD does not replace model tests but has very important role in overall ship design process. In recent years CFD techniques have developed fast and now seems to be that the computation time is the bottle neck of development. In Figure 5 example of CRP propeller couple that has been built from detailed grids.

In figure 6 are shown principle of two cylindrical drum domains that includes the rotating propellers inside. design process It is recommended that both propellers are to be designed always by one designer. This way all aspects of above explained complexity of flow around the propellers is taken into account. If propeller design tasks are separated risk of failure is larger because the interface between propellers is difficult to determine. Also the performance responsibility is easier to control if there is one responsible design party.

Nevertheless very close co-operation between ship designer, shipyard and propeller designer is required when the propulsion system is defined and designed. |||

crp azipod

effective wake field. It is important to have all components included in the initial forward propeller design wake field because the error will multiply in downstream flow where the after propeller is operating (Fig. 3). After propeller has small influence on forward propeller that needs to be taken into account as well.

The second wake field is the one where the after propeller is operating. This wake field is complicated, because it includes everything what is in the flow in front of the after propeller but also effect of pod hull structure behind the pod propeller. The wake field has now effect of forward propeller indeced velocities added to the flow (Fig. 4). This means that there is large amount of rotation included which needs to be recovered with after propeller. After propeller is not going to recover all because it is smaller than forward propeller slipstream radius, because it has to be able to make small steering movements inside the forward propeller slipstream.

ABB has studied this complexity of flow conditions extensively. The knowledge of correct inflow to the forward and after propeller is utmost important.

This is why ABB has put lots of effort to research this field and has achieved excellent results. The design philosophy has changed so that the role of Computational Fluid Dynamics (CFD) has taken more pronounced role in design process than it has had before.

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Educating the next generation of crew Achieving safe and optimal performance on board todayâ&#x20AC;&#x2122;s advanced vessels, and at the same time securing fuel savings in operation, as well as safe and reliable maintenance, demands systematic crew education.

That is where the technical installations at the ABB Marine Academy in Singapore come in. authors:

Eric Leong â&#x20AC;&#x201C; eric.leong@sg.abb.com ||| Ding KokKin ||| Chua HoonHong ||| Nigel Chua

until the recent global economic crisis,

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offshore rig construction had been experiencing its largest growth in 20 years, requiring new and skilled employees in ever increasing numbers. The current global economic crisis and the slowdown in the oil exploration boom have given the offshore and marine industry an opportunity to enhance capabwwilities and develop human resources during the lull.

With a large proportion of new crew members coming from Asia, coupled with Singaporeâ&#x20AC;&#x2122;s 70% market share in offshore rig construction, and its growing presence as a supplier of advanced offshore support vessels (OSV), the ABB Marine Academy was set up in Singapore in June 2007. As an ideal location to provide training, Marine Academy Singapore focuses on Oil & Gas-related vessels.

Hands-on training on a medium voltage drive.

Marine Academy Singapore is furnished with a wide range of equipment that is equivalent to that installed on board vessels, providing plenty of opportunities for hands-on experience that crew members usually cannot obtain on a working vessel.

Marine Academy offers training for safety, operation and maintenance of electrical systems. Operating with higher voltage equipment means that the crew has to have a higher awareness of safety. Marine Academy therefore offers DNV-certified marine high voltage safety courses. Furthermore, standard or tailor-made training on vessel operations with advanced electrical systems, such as electric propulsion and drilling drives is offered.

A competent work force is more productive, operates at reduced risk levels, achieves shorter down

The Marine Academy offers a set of standard training courses, of which the following are now available: the courses

ELE33

ELE32

G163

ELE22

HV10

DRL10

DRL11

Marine LV Switchboard & Safety Course Low voltage switchboards Marine MV Switchboard Course Medium voltage switchboards ACS800 Liquid-Cooled Drives Course Low Voltage Frequency Converter: ACS800 Liquid-Cooled ACS6000 SD/AD Course Medium Voltage Frequency Converter: ACS6000 SD/AD Marine High Voltage Safety Course DNV-certified marine high voltage (>1kV) safety courses Drilling Drives Course for Jack-up Rigs Drilling drives and controls, includes training on ACS600 or ACS800 drives Drilling Drives Course for Semi-Submersibles and Drill ships Drilling drives and controls, includes training on ACS600 or ACS800 drives

In addition, the training centre also develops tailormade training programmes together with the operator or owner of the vessels. Such training programmes may include training of a specific system installation and configuration or simulator-based remote control of electric propulsion.

A permanent staff of trainers is responsible for training. In addition, external experts familiar with the various systems and vessel types are engaged to give specialised extension training, depending on the

technical level set for the trainees and the objectives of the courses.

Marine Academy Singapore is equipped with fully operational equipment in a safe environment for hands-on training of operations, fault finding, and maintenance.

The equipment is of the same type as that used in the most recent deliveries to the new and growing fleet of vessels, with advanced electrical installations such as: – ABB Unigear medium voltage switchboard – ABB ACS6000 medium voltage frequency converter – ABB ACS800 low voltage frequency converter (both Liquid-Cooled and Air-Cooled) – ABB Stadt low voltage frequency converter (Q2 2010) technical installations

UniGear is a metal-clad, arcproof, air-insulated switchboard suitable for medium voltage distribution, designed for voltages up to 24kV, and typically used in 6kV or 6.6kV and 11kV marine installations.

Three power compartments and an auxiliary compartment are segregated by means of metallic partitions with highly effective use of space when fitted with double-level units. All compartments are accessible from the front.

Start-up, maintenance and service operations can be carried out from the front. Complete safety interlocks guarantee correct operating procedures.

Apparatus range includes gas (HD4) and vacuum circuit breakers (VD4, Vmax), contactors (V-contact) and switch-disconnectors. The earthing switch is operated from the front and is provided with safe and reliable position indicators.

The UniGear comes with four distinct safety features to ensure the operator is well protected when working with, or near the equipment; such as interlocks with keys, padlocks, and locking magnets.

This arc-proof unit features both passive and active internal arc protection. Passive protection includes an individual flap in every power compartment.

The flap opens due to high pressure when an internal arc occurs. Active protection comes with two options in the marine versions; pressure or light sensors. unigear® switchgear

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times, and suffers fewer injuries. With the introduction of new electrical propulsion system equipment and drilling system equipment, both existing and new crew need operating and maintenance training.

When a vessel is out at sea, such training can be critical: here, downtime is measured in terms of millions of dollars per day, while additional fuel consumption through sub-optimal operation of power plant may also an owner cost dearly, as well as causing higher environmental emissions.

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Electronic protection and measurement systems using REM and REF relays can be fitted with conventional instrument transformers or new generation sensors. These modern relays include human-machine interfaces that are easy to navigate. Relay settings can be modified locally. Alternatively, configurations and settings can be downloaded to the relays using the CAP505 software and a data cable.

The UniGear equipment in Marine Academy Singapore consists of two single-level and two doublelevel units.

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1. A Single-Level Compact Unit for transformer protection. This has a Vmax vacuum circuit breaker that is smaller in size than other similar medium voltage circuit breakers.

2. A Single-Level Unit for generator protection.

This has a HD4 SF6 gas circuit breaker in the apparatus compartment.

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UniGear MV Switchboard

3. A Double-Level Unit for motor switching and protection. Here, the bottom compartment is installed with a V-contact vacuum contactor and the top compartment is left empty for future expansion.

4. A Double-Level Unit for transformer protection.

In this case, both top and bottom compartments are installed with a HD4 SF6 gas circuit breaker. Each one protects a transformer.

UniGear is installed on vessels where the installed power level needs to be high, and typically where installed engine capacity is more than about 10MW. This power range would include semi-submersibles rigs, large jack-up rigs, drillships, LNG carriers, and FPSOs in the oil and gas segment, as well as cruise ships, ferries, and ice breaking vessels.

Marine Academy Singapore has an ACS6000 SD/AD for training purposes, with the following configuration: LSU Line Supply Unit (12-pulse rectifier diode) - the LSU rectifies the AC line voltage and supplies electrical energy to the DC link capacitors of the CBU. COU Control Unit - the COU incorporates the hardware for control, monitoring and protection functions of the inverter. The COU also includes the interfaces to the local control panel on the front door and to a higher-level process control system.

INU Inverter Unit (7 MVA) - the INU converts the DC voltage to the AC motor voltage. The self commutated, 6-pulse, 3-level voltage source inverter allows four-quadrant operation.

CBU Capacitor Bank Unit - the CBU smoothes the intermediate DC voltage and de-couples the rectifier from the inverter. The CBU contains DC link capacitors, a charging unit and an earth isolator.

WCU Water Cooling Unit (Closed to atmospheric pressure) - the WCU feeds the cooling water to the main power components, transfers the heat to an external water circuit and continuously purifies the internal cooling water.

EXU Excitation Unit: 6-pulse thyristor bridge or AC power controller for synchronous motor drives.

In Marine applications, the ACS6000 is used as the main propulsion systems, as high power thruster drives, and for variable speed pumps and compressors, normally for motors with rated power above 4-5MW. These will include drillships, LNG carriers, cruise ships, ferries, and ice breakers.

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medium voltage drives ACS6000 AD/SD medium voltage drives are used for speed and torque control of synchronous or asynchronous motors of 3–27 MW, up to 3.3 kV. The ACS 6000 is a modular drive designed for single-motor or multi-motor applications.

Delivering precise process control through ABB’s patented Direct Torque Control (DTC®) ensures the highest control accuracy without the use of an encoder, despite input power variations or sudden load changes. Adapting to power demand as necessary optimises energy consumption.

Some important key product features are: – Active Rectifier Unit for four-quadrant operation and reduced harmonics.

– Line Supply Unit for constant power factor of 0.95 over the whole speed range.

– Common DC Bus for multiple machine operation and energy recuperation.

– Modular Design for optimum configurations.

– IGCT power semiconductor for highest reliability – DTC control platform for exceptionally high torque and speed performance.

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ACS6000 medium voltage (3.3kV) frequency converter low voltage drives ACS800 drives are used to control the speed and torque of standard induction motors - the workhorses of the industry. AC drive technology extends the motor speed range from zero to high above the rated speed, increasing the productivity of the driven process. When a low capacity is enough, the drive reduces the machine speed and saves energy and fuel consumption. The AC800 is a modular drive designed for single-motor or multi-motor applications with independent inverter units.

An inverter unit contains the components required to control one motor. These include one inverter module or several inverter modules connected in parallel, together with the necessary auxiliary equipment such as control electronics, fusing, cabling and switchgear.

ACS800 inverter units range from 1.5 to 5600 kW in power, and employ inverter modules from frame sizes R2i to R8i. Up to 560 kW, inverter units consist of one module only; higher powers are achieved by connecting multiple R8i modules in parallel. Each inverter module is equipped either with a DC switch/disconnector or with DC fuses only.

ACS800 Liquid Cooled low voltage drive

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Multi motor drives are types of industrial drives built from industrial drive modules connected to a common DC bus arrangement enabling single power entry and common braking resources for several drives. The DC power is derived from a single supply unit built into the same installation. There are several possibilities on the supply side starting from a simple diode supply unit and ranging up to highly sophisticated active IGBT supply units. This construction simplifies the total installation and results in many benefits: savings in cabling, reduced installation and maintenance costs, reduced line currents, and more.

A diode supply unit is used in non-regenerative drive systems to convert three-phase AC voltage to DC voltage. A 12-pulse bridge configuration can be implemented with the unit supplied by a three winding transformer with a thirty degree phase shift between secondary windings. In resistor braking, whenever the voltage in the intermediate circuit of a frequency converter exceeds a certain limit, a braking chopper connects the circuit to a braking resistor. The drive is also available with active rectifiers, where regenerated power can be transferred to the network, with close to sinusoidal load currents, without the use of multipulse rectifiers and transformers.

Each inverter has a motor control unit (DCU) which contains the RMIO board and optional I/O modules.

Several different I/O extension modules for different functions such as control, monitoring and measurement purposes are available. A separate pulse encoder interface module is also possible. Other optional features include the prevention of the unexpected

start-up of the inverters to provide a safe interlock for the system. Typically, a PLC-type controller, AC800M, is used to control and monitor each drive line-up. The controller can be redundant.

The liquid-cooled version of the converters utilises direct liquid cooling which makes it extremely compact and silent, and reduces the need for ventilation or air conditioning.

ACS800 drives are used as drilling drives on Jackup rigs, semi-submersible rigs, and drillships. They are also used as thruster drives on semi-submersible rigs and in ship applications. Marine Academy Singapore’s facilities include both the ACS800 liquid cooled drive and the ACS800 air cooled drive.

Stadt Marine drives are low voltage drives designed specifically for marine applications. They are predominantly used on marine vessels as main propulsion, tunnel and azimuthing thruster drives. The key features of the Stadt Marine drive are that it is: – Compact – Light in weight – Simple in Construction – Safe and offers very efficient water cooling – Modular – Easy to maintain – Low voltage (400 to 690V supply) The Stadt drive is used in a variety of vessel types, especially in cases where there are restrictions on the permissible size of the equipment’s footprint. These include, but are not limited to: AHTS (Anchor Handling and Tug Supply vessel), Icebreaking Supply Vessel, LWIV- Light Well Intervention Vessel, OSCV (Offshore Subsea Construction Vessel), OSV (Offshore Supply Vessel) or PSV (Platform Supply Vessel), Patrol Vessel, Rescue Vessel, Research Vessel, RoPax/Car and Passenger Ferry and ROV (Remotely Operated Vehicles) Supply Vessel.

Marine Academy Singapore will receive a Stadt 4-AC-1-2 400Vac supply, 1000kA frame size and 12-pulse rectifier supplied with a complete water cooler unit. It will include a control and interface unit, D12/A – DSU, and one inverter, all in one line-up. |||

Voltage and frequency control The discussion on whether to use isochronous or speed droop control of the diesel engines in ship electric power plants has been ongoing since gen-sets were introduced in marine. This paper elaborates on the characteristics of the two methods, while the answer to the ultimate question, “Which method is the better?” remains unanswered.

Alf Kåre Ådnanes – alf-kare.adnanes@no.abb.com

load sharing The electric loads of the generators can be described as: - Active load (kW) - Reactive load (kVAr) Rules and regulations require that these loads shall be equally shared between paralleled gen-sets in the plant. This means, that two equally sized gensets shall have the same load in kW and kVAr within the tolerance being defined by the classification rules.

Gen-sets of different size, share the loads to an equal percentage of their rating. The load sharing shall be automatic – of course with the possibility of unequal sharing for test purpose, or if procedure requires it e.g. after longer times of low load operation. reactive load sharing The reactive load sharing is controlled by the automatic voltage regulator (AVR).

The generator voltage in ship networks is allowed to vary, typically up to 5%. Utilizing this freedom, and by use of digital AVR with high resolution and performance, the voltage regulation is made by setting the AVR in droop control mode, allowing the voltage to reduce with increasing reactive load; Figure 1. The two paralleled generators will by equal setting of the voltage reference value Vref, and the droop Dv, share the reactive load equally.

There are solutions also for sharing the reactive

load equally without voltage variations, but this requires communication between the AVRs and hence increased complexity and potentially common fault modes. Since the operation, synchronization, and performance of the electrical power plant for most installations well tolerate a small voltage variation, voltage droop control without droop compensation is the absolutely most common solution for marine vessels. active load sharing The active load sharing is controlled by the diesel engine speed controllers, the Governor, Figure 2. By controlling the speed of the diesel engine, also the frequency of synchronous generator is directly controlled. The diesel engine may well be controlled in speed droop control, similar as the voltage droop control of the generators, with a control scheme as shown in Figure 3.

The loads of the plant may vary significantly, as shown in Figure 4. This plot was taken during a sea trial of a semi submersible drilling rig, for the purpose of testing the power plant stability.

Fuel valve Fuel

Diesel engine

Generator Electric load Flywheel

Actuator

Speed pickup

Speed feedback

Governor

Generator voltage Vref

Speed reference

Generator 1 Dv

Paralleling - Equal magnetization - Reactive load sharing

Reactive load

Figure 2: The Governor in the speed control loop of a diesel engine.

Generator 2 Speed reference

100%

Figure 1: Automatic Voltage Regulator in droop control mode.

+ +-

e -

PID Controller

Actuator

Diesel Engine

Generator

Speed feedback

Droop

Active load (kW) feedback

Figure 3: The speed droop control scheme for a governor.

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author:

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Active load (kW) feedback

Droop Speed feedback Speed reference

+ ++

-

PID Controller

Actuator

Diesel Engine 1

Generator 1

Diesel Engine 2

Generator 2

Average Load Calc.

Speed reference

+ + -

-

PID Controller

Actuator Speed feedback

Droop

Active load (kW) feedback

Figure 5: Isochronous speed control scheme for governors, two paralleled gen-sets.

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Figure 4: Measurement of load variations in a semi submersible drilling rig.

Large power variations in the load are challenging for the diesel engine controller, and will cause frequency variations. While the voltage variations from droop control of the generators do normally not have detrimental effects for the operations of the electric system, large frequency variations will make higher losses in the plant, and may also make synchronization of generators more difficult. This is even if the speed reference is being adjusted by the power management system, as this compensation of the droop is normally slow.

The isochronous speed controller shown in Figure 5, will not eliminate frequency variations due to its control bandwidth, but it reduces the excursions from the set-point quite efficiently for most normal load variations.

The characteristics of these methods can be summarized as: Droop mode: - Larger frequency variations with varying loads - Lower margins to over- or under frequency trips (can be compensated by power management speed reference adjustments) - No single point of failure in the controllers, if the power management system has an overall load sharing control and speed reference adjustment, a failure there has no instant impact on the power plant

Isochronous mode: - Quick response to load changes / frequency variations - Stable net frequency even with variable loads, ensuring larger margins to critical under- and over speeds trip limits - Asymmetric load sharing requires additional functionality, e.g. mode change - Failure in load sharing line (earth failure, short circuit) may be a single point of failure.

Monitoring of load sharing line is required with automatic switching to droop mode when fault is detected conclusion As each vessel type has different operational requirements and load characteristics, the answer to the question â&#x20AC;&#x153;Which method is the better?â&#x20AC;? cannot be easily answered.

For many ship types, especially smaller vessels where the thrusters and propellers may be strongly disturbed by the water motion and air suction in harsh weather, the use of an isochronous speed control scheme, Figure 5, is more commonly in use. This stabilizes the network frequency, and simplifies synchronization of generators and bus ties in harsh weather.

To increase the flexibility of controls, the governors are normally equipped with mode change enabling also operation in speed droop.

For other ship types, like drilling vessels, the thrusters are less exposed to the weather impact, and even with large variations in the process loads, speed droop is normally used. Normally, the automation systemâ&#x20AC;&#x2122;s power management is allowed to adjust the speed reference to keep the frequency more stable close to the set-point, and thereby also increasing the margins to over- and under-frequency trip limits. |||