EEWeb Pulse - Issue 75

INTERVIEW

EEWeb Issue 75

December 4, 2012

Tim Jenks President and CEO NeoPhotonics SPECIAL FEATURE

MCU Wars - Episode 2.1: Developing in an RTOS TECHNICAL ARTICLE

Distribution Systems Automation and Optimization Part 2

Electrical Engineering Community

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EEWeb PULSE

TABLE OF CONTENTS

4

Tim Jenks NEOPHOTONICS Interview with Tim Jenks - President and CEO

Featured Products

11

MCU Wars 2.1: Developing in an RTOS

12

Two experts in RTOS sit down to discuss the advantages of using a Kernel when developing in a real-time system.

18

Distribution Systems - Part 2

BY NICHOLAS ABI-SAMRA WITH QUANTA TECHNOLOGY Why Distribution Automation (DA) is considered in developing the Smart Grid as it transforms the distribution network towards more automation.

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RTZ - Return to Zero Comic

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EEWeb | Electrical Engineering Community EEWeb | Electrical Engineering Community

INTERVIEW INTERVIEW

Tim

Jenks NeoPhotonics

NeoPhotonics is a leading provider of optical components that enable the delivery of video, voice and data over telecommunications and data networks. We spoke with Tim Jenks, the President and CEO, about their cutting-edge photonic-integrated circuits, what sets them apart in the industry and how they are connecting the world via optical networks.

Visit www.eeweb.com www.eeweb.com Visit

527

EEWeb PULSE How did you get into engineering?

old and was founded by two people, Nobuyuki Kambe, a I grew up in southern California Japanese PhD, and Xiangxin in San Diego and I’ve always (Sean) Bi, a Chinese PhD, both been something of a mechani- of whom went to graduate school cal “tinkerer.” In high school, I in the U.S. They really wanted was pretty active in things rang- to explore novel approaches for ing from music to sports, but I using nanomaterials. Ultimately, also spent a fair amount of time the use of nanomaterials was with my friends working on cars, intended to look at things from which were some of the cool electro-chemical materials to things to do in southern Califor- optical materials. The early days nia at the time. In school, I was al- were looking for improved glass ways good at math and science, formulations for optical chips as so engineering was a pretty natu- well as high-rate batteries that ral direction for me. I went to col- were eventually implemented lege at the U.S. Naval Academy, in products. Back in 2002, after where I majored in Mechanical the telecomm boom and bust Engineering and Marine Engi- period, we divided the company neering (which is focused on into three different market verthings like ship power plants). I tical directions; NeoPhotonics also got into materials science at continued in glass materials and the time, which was among my optical applications while two favorite classes, and went on to spin outs, NanoGram Corp and graduate school at MIT, where NanoGram Devices, pursued I studied nuclear engineering. other market directions. This alAfter that, I went into the Navy. lowed NeoPhotonics to focus on My first work experiences were photonic-integrated circuits for really operating nuclear propulsion plants at sea. After the navy, I went to business school at Stanford and then joined Raychem Corporation, which was a materials science company. It was at Raychem that I first dealt with fiber optic products, so when I left Raychem I joined what was then NanoGram Corporation and is now NeoPhotonics Corporation.

It was a combination of having had an interest in fiber optics and materials science that put me on a path to this company.

Can you tell us more about NeoPhotonics?

The company is about 15 years

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“By being a light processor, the idea is that it’s an integrated circuit to which you connect an optical fiber that inserts light.”

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communications and to subsequently pursue acquisitions to acquire new technologies and accelerate growth.

Since the early days, what has been the best product you’ve produced?

In terms of products, the core product technology—what we call photonic-integrated circuits (PICs)—are devices that process light as light. By being a light processor, the idea is that it’s an integrated circuit to which you connect an optical fiber that inserts light. Rather than having traces of metals, which would conduct electricity on a semi-

INTERVIEW conductor chip, there are traces of glass or semiconductor material that are called waveguides, which conduct or route or switch light. The idea is that fibers will inject light into the chip and the waveguides and other structures do the processing. We fabricate the chips and we put them into modules that we can connect to a fiber-optic network. They work like a large-scale integration platform in semiconductors—you can replace 100 different discrete devices with one of these chip-based devices. You can then manufacture the chips using semiconductor tooling in large quantity mass fabrication so ultimately, much like the anal-

ogy of electrical semiconductors, making optical-integrated circuits so that they are highly repeatable and highly reliable and provide high-quality, low-cost designs. The products have names like “Variable Optical Attenuator Multiplexer,” or “Integrated Coherent Receiver,” and other nonhousehold names for a product.

Can you describe the process of making one of these photonic-integrated circuits?

If I can draw the analogy of making a device that’s like a sandwich; think about a sandwich as an upper and lower layer of bread, and the active ingredi-

ents being between them. Our wave-guides are in the middle of an upper and lower cladding (the “bread”) and the middle of the sandwich is strips of glass that are higher index of refraction; these conduct the light. Instead of having transistors as you would have in electronic ICs, PICs can have detectors, filters, switches that direct the light or even attenuators that can reduce the “gain” of the light. You can also build lasers into semiconductor PICs. You can integrate a number of these devices into the chip and connect them all with the waveguides; then you connect the waveguides to fibers. It is a direct analogy to electronic chips, except that the devices are optical devices as opposed to transistors.

Are you a fabless company?

No. Actually we operate our own fabs in Silicon Valley. Our process uses standard semiconductor industry tools, but the devices we actually make have some customization that we do in our fabs.

How small are the features of these PICs?

We use normal lithography processes. The size dimension of light requires a certain amount of “real-estate”. Therefore the devices don’t get microscopic in size; they tend to be the size of a fingernail. They can also be bigger than that, up to a square inch, but most of them are smaller. Those that are built into semiconductor materials, in particular indium-phosphide, tend to be much smaller around a few Visit www.eeweb.com

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EEWeb PULSE millimeters. The higher the index of refraction, the smaller the device. If you imagine putting light on a chip, the light doesn’t actually make 90º turns, but tends to make tight bends in a waveguide. So there needs to be a bit of real-estate in order to make a tight bend, which is why these devices tend to be measured in millimeters to centimeters.

“We make devices that would go the home or the basement of the a essentially convert electrical and o which are the source of your high-s

Are the lasers used for communication as well?

I mentioned that we have two fabs in Silicon Valley — one makes glass and one makes indium phosphide. There are devices that generate light—that convert electrical signals into light or that convert light signals into electricity—which are semiconductor lasers or semiconductor photodiodes and are made of indium phosphide. There are also a range of devices that can bend switch filter or otherwise aggregate channels or balance light signals. Those are often built in glass and referred to as silica on silicon (SiO2 on Si).

Do you sell individual components or are they all module-based?

Most all of our products are module-based. The modules are often sold as components, so they would be used in telecom transmission equipment or plug into a server or router. Our customers are all of the world’s largest manufacturers of telecommunications network equipment.

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Going forward, do you see your company going into other industries besides the standard telecommunications products that you are in now?

There are a number of other areas that use technologies that can be viewed as adjacent, rang-

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ing from data storage to medical diagnostics and therapeutics to industrial sensing applications.

Essentially, what we do today goes into telecommunications, but just to give you an idea of where that goes; we make devices that are in fiber to the home

INTERVIEW

to the side of apartment and optical signals, speed internet. “

net. The traffic that runs in fiber optic cables gets aggregated in a central office. We also sell modules that connect central offices of the telephone company to large data centers. Whether the data center is one that brings you Netflix video or connects Google to the network, or any of the big social media platforms, they also get connected to these types of modules. Because it’s in the telecommunications network, those networks go all over the world in every country and every city right down to very small villages in the remote countryside.

There’s a lot to do with connecting the world via optical networks. Cell phones are typically thought of as a wireless device, but it’s really only wireless for about a half a mile and then it’s fiber-optic. Since everything is fiber optic, there are a number of adjacent markets. It used to be telephone lines, but now everything related to delivering digital content to you anywhere, anytime, is fiber optics.

nical one, but it’s also one where people work together across international borders to solve problems and invent devices, which is a fun aspect of the company.

For more information about NeoPhotonics, visit their website:

www.neophotonics.com

What is the culture like at NeoPhotonics?

NeoPhotonics is a “technicallyheavy” company. We have a strong R&D team in Silicon Valley. We also have research fasystems (for example, this could cilities in China, in Canada and include Verizon’s FiOS system). in Japan. We do heavy duty with We make devices that would go graduate-level engineers, parto the side of the home or the ticularly electrical engineers and basement of the apartment and physicists, but also process enessentially convert electrical and gineers and chemical engineers optical signals, which are the due to the nature of our fabs. The source of your high-speed inter- culture, therefore, is a pretty tech-

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Episode 2.1

Developing in an RTOS

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SPECIAL FEATURE

In this episode of MCU Wars, we spoke with two experts in real-time systems: Richard Barry, founder of freeRTOS, and Jean Labrosse, President and CEO of Micrium. The discussion ranges from the advantages of using a Kernel in your product to why these companies offer their source code to their users.

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What’s the difference between RTOS and Kernels?

Absolutely. We like to define the difference between an RTOS and Kernel as; the Kernel is really a multi-tasking portion Jean of a real-time operating system and a real-time operating system contains more than just the Kernel. It’s TCPIPstack file-system GUI, USB-stack device, so for us, an RTOS is not just a Kernel unlike what the popular belief is in the industry. RTOS for us is really more than just a kernel.

Why would a user want a Kernel in their product?

Well, firstly I would say that even though I provide an RTOS or a Kernel, I wouldn’t Richard say that everybody shouldn’t always use one—it’s very much a matter of the right tools for the right application. As soon as you get into any kind of complexity in timing, communications interfaces, something that’s maintainable over a long period of time, something that is robust and can control the execution, you come to a point where it’s easier to use a Kernel than not to use one. Communication interfaces are really the point in which the complexity gets big enough to warrant using a Kernel and it would really make your life easier.

Basically, an RTOS provides a framework for building upon applications. So instead Jean of being boxed into certain things that you can or cannot do, it becomes very interesting to have a Kernel, especially when you’re considering, as Richard was saying, TCPIP file-system GUI—all these applications require a lot of CPU processing time and you wouldn’t want to have a single thread of application handle those specific modules. So an RTOS Kernel, per se, is a good foundation to build your application on.

I think one of the key points, for me, is maintainability. You can write any Richard application without an RTOS, but as soon as you add in extra functionality or change the hardware platform you are

14

From the left: Cody Miller of EEWeb, Richard Barry of freeRTOS running on or change the optimization, you don’t want your application to behave differently. Maintainability, to me, is everything in software development and that’s a Kernel really helps with that.

Both of you offer your source code to your users. Could you give us a few reasons why that’s valuable to the user?

We don’t use the word “open-source” because in the industry, open-source is viewed as free software to use in your Jean application. In our case, our software is authored in source-form for free evaluation. But we expect customers to license our product once they decide to use it in a commercial setting. We provide software in source-form because it makes it a lot easier for customers to actually tailor the software, if they need to, for their application.

It’s a lot easier to work with different compilers, it’s a lot easier to work in different environments, different

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SPECIAL FEATURE

“Communication interfaces are really the point in which the complexity gets big enough to warrant using a Kernel and it would really make your life easier.”

S and Jean Labrosse of Micrium processors, so having the software in source-form is a huge advantage to customers. They see the quality of the software as not like you’re hiding behind the object code that’s very important—we put a tremendous amount of pride in creating the best looking software you can put your eyeballs on.

I agree with Jean that having the sourcecode is very important. There are Richard people that say, “if you want to support a product, you can only give it to people in binary form, because as soon as they start changing it, then it becomes unsupportable,” which is absolutely right. If people do start changing it, then we can’t support them, so they can change it if they want, but then there are limits to what Jean or I can do to help you from that point. Counter to that, I think that when you have the source code, you can see how much is working and it’s much easier to debug. You can also step through the code—if you think there’s something wrong, you can see exactly what the code is doing, whether it’s doing what you expect it to do or not.

source.” It’s not open-source in the traditional sense—it is a free part that you can download in source form and once you’ve downloaded it, it is effectively open-source to you, so you can modify, distribute it and even sell it. The reason it differs from traditional open-source is that the way we have developed the whole product is to try and remove all of the objections that people have to using open-source. One of the major objections is that there’s ambiguity in IP ownership. You don’t want to build something into a product that sells millions of units and then find that you have a problem because you’ve accidentally put someone else’s IP in it. So when people contribute back to free RTOS, all that code is made completely available for free to everybody, but is kept separate from the core product, so that we know where everything came from.

Continued in Part 2...

To view this episode of MCU Wars and other EEWeb videos:

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15

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Distributio Systems Automation & Optimization Part 2

Nicholas Abi-Samra

Vice President, President ofAsset Quanta Technologies Vice Management - Quanta Technology

Present day Distribution Automation (DA) goes beyond reducing manual procedures. DA makes distribution systems more controllable and flexible based on accurate data for decision-making applications. This is accomplished through a set of intelligent sensors, processors and fast communications to remotely monitor and coordinate distribution assets.

DA is considered a foundation to build upon in developing the Smart Grid as it transforms the distribution network towards more automation.

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TECH ARTICLE

on

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EEWeb PULSE V. FAULT DETECTION, ISOLATION AND SERVICE RESTORATION (FDIR) OR FAULT LOCATION, ISOLATION, AND SERVICE RESTORATION (FLISR) FDIR and FLSIR are interchangeably used terms which refer to the same feeder fault management approach.

Basically, this approach is divided into: 1. The fault detection and isolation step 2. The decision support and procedures necessary to reconfigure system and restore (R) power to customers.

They are made of the following elements: • Detection that an outage has occurred • Determination of the location of the fault • Isolation of the faulted section • Re-energization the un-faulted sections of the feeder FLISR is able to restore service in one minute or less following the initial fault, resulting in significant reliability improvement compared with the traditional manual restoration process.

the true fault location is closer to the substation. Since the fault impedance tends to be purely resistive, another alternative is to do the calculations considering only the reactive component of the impedance values.

FLSIR Centralized or Decentralized FLISR applications can utilize decentralized, substation, or control center intelligence. Each FLISR approach has benefits and drawbacks.

Some utilities could determine whether a limited deployment of intelligent switches in a decentralized or substation organization will be sufficient to improve the worst-performing feeders (WPF) without a full rollout.

Other utilities may approach FLISR on service-area wide through distribution management system (DMS) implementations.

One approach could be to provide C&I customers with local switches organized into a peer-to-peer, ultra-fast decentralized system utilizing deterministic communications, while consumers, with less demanding needs, could have FLISR run through the control center DMS or the substation.

Fault Detection Methods – Then and Now

Approach

Benefits

Drawbacks

Then… Local fault passage indicators tripped by the passage of a high current above a certain threshold have traditionally determined fault locations. Field crews had to travel to each fault indicator site to see if it was set or not.

Decentralized

Requires least bandwidth Scalable Fastest restoration of feeder Lower introduction costs

Lacks overall system view Still report status on backhaul communications systems

Substation

Scalable Processed information requires lower bandwidth backhaul communication than peer-to-peer

Reliable processing in substation Lacks overall system view, but more than peerto-peer Slower restoration time than peerto-peer

Control Center

Full system view for restoration

Slowest restoration times Requires the most bandwidth Requires a DMS

Now…Telemetered fault indications by a SCADA/ DMS system and used by the in conjunction network topology model – to determine the section of the feeder in which the fault has occurred based on measured phase voltage and current waveforms. When a feeder has a tree-like structure with multiple branches, several theoretically possible fault locations – all having the same network impedance – may exist.

Challenges for Accurate Fault Locating

(peer-to-peer)

A source of error when estimating the fault location from fault impedance measurements is that the fault impedance itself is not known. If the fault has significant impedance, the estimated fault location (assuming zero fault impedance), may be further away from the substation than the true location.

VI. AUTOMATION FOR LARGE SUBSTATIONS

Nonetheless, this information is still very useful since the estimated fault location distance from the substation is an upper boundary, and dispatchers can know that

Substation automation (SA) is not new. Substations have been equipped to perform automatic reclosing, automatic bus sectionalizing, automatic load transfers,

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Table 4: Different Deployment Techniques for FLISR

EEWeb | Electrical Engineering Community

automatic capacitor switching, etc. for many years using a combination of control panels, auxiliary relays, switches, transducers and exclusively with copper wiring. Today SA encompasses the deployment of operating functions and applications to enhance operation and maintenance (O&M) efficiencies and optimize the management of capital assets in substations. It involves integrating protection, control and data acquisition functions and includes deployment of supervisory control and data acquisition (SCADA), equipment condition monitoring, volt/var control and alarm processing, etc. Some of the other functions of SA: Today SA includes functions such as: • Automated retrieval of data • Automatic generation of switching sequences

TECH ARTICLE

At least from a logical point of view, SA systems comprise three levels, as shown in Figure 3. There is not only vertical communication between the levels (e.g., between bay and station level), but also horizontal communication within the level (e.g., in the bay level between bay units for functions like interlocking).

For new substations, the Substation Automation systems are specified as part the overall specification taking into account all the relevant interfaces. For retrofit, the SA system is specified stand-alone but referring to the dedicated requirements of the existing substation as boundary. All functions needed are specified either from the functional point of view only or by referring to some predefined devices meaning control, protection and monitoring units.

Today, SA uses Intelligent Electronic Devices (IED) as the primary source of data from the substation and local Area Network (LAN) to transmit data and control commands, and can perform many functions in addition to the legacy ones. Communications with substations have taken forms including leased or dedicated telephone lines, cellular, satellite transmissions, fiberoptic networks and radio.

• Detection of fault location • Diagnostics of system disturbances • Equipment diagnostics through sensors • Load shedding • Local & global alarm & warnings • Physical Security enforcement

Wide Area Network

• Protective Device Coordination • Supervision of interlocks

Station Level

Bay Level

Station Host

Protection

Station HMI

Control

Data Gateway

Protection

Bay #1

Process Level

Sensors

Control

Bay #n

Actuators

Sensors

Equipment #1 Figure 3: Substation Automation Levels

Actuators

Equipment #n

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VII. DATA INTEGRATION FOR SA

• Communication architecture (network and protocol)

Substation data integration poses a number of challenges, a large number of which are solved by IEC 61850. Integration of substation IED data often called “data warehouse” or “data mart”. Recorded event data collected from various substation IEDs. This includes acquiring, or collecting, data which may in the form of measured analog current or voltage values or the open or closed status of contact points. Acquired data can be used locally within the device collecting it, sent to another device in a substation, or sent from the substation to be used by different users, including system operators. This data needs to be “translated”, audited, and prioritized before it is sent along. Similarly, control data or command messages need to authorized and authenticated. This is depicted in Figure 4.

• Data processing and storage

Application of Substation Automation for Condition Monitoring

Sensors for substation condition motoring can be simple or complex, depending on the parameters to be monitored and monitoring techniques as shown in the Table 5 for transformer condition monitoring. Sensors are also used on other such as: surge arresters, circuit breakers, instrument transformers, capacitor banks, station batteries, etc.

Substation automation includes several topics, such as: • Data acquisition (sensing and monitoring techniques, and “intelligent” capture)

• Diagnostics • Maintenance • System integration VIII. ELEMENTS OF SUBSTATION EQUIPMENT CONDITION MONITORING – AN EXAMPLE OF SA An open-system approach, based on IEC 61850, can be an effective and efficient solution for equipment new and existing substations. Some of the major advantages of such a solution includes the following components.

Sensors

s

Substation Security Perimeter

Figure 4: Substation Automation Example

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EEWeb | Electrical Engineering Community

TECH ARTICLE

Sub Monitored/ Purpose

Example of Monitoring Techniques

o Data for archiving (for later analysis and retrieval)

Gas in Oil

Hydrogen sensor Multi-gas-in-oil sensor (besides hydrogen)

• On-line expert systems: May include patternrecognition, or neural-network processing for complex analysis and data reduction. Decisions made based on:

Top Oil and Winding Temperatures

Top Oil RTDs Externally mounted sensors Winding Hot-Spot Older techniques: Thermistors, RTDs Newer (Fiber-Optic) Extrinsic Fiber carries signal to external sensor and Intrinsic Fiber itself is the sensor Analogy and electronic simulating

Overheat, arcing, partial discharge, insulation aging

Operation condition assessment

Water contents in the oil (moisture)

o Design of component

o Operating conditions

o History of that component’s performance,

o The results of any off-line testing/off-line inspections • The local expert system must provide answers to four fundamental questions, at the time anomalous conditions are detected:

Thin-film capacitive element technology to calculate water ppm

o “What’s wrong?”

o “What action should be taken?”

Electrical methods Acoustic methods UHF methods

o “How long before action must be taken?”, and

o “What will happen if no action is taken?”

Oil Pump

Sensors to sense changes in gap between shaft and bearing surface

Based on the above, SA could reconfigure the system rapidly to maintain availability of the power throughput of the substation.

Load Tap Changers (LTC)

LTC tank temperature Gas-in-oil in LTC Tap position LTC motor current and torques Elapsed time of tap changing Vibration Acoustic signature Start/Stop cycle

Oil dielectric strength

Partial Discharge Oil/Paper insulation

Bearing wear assessment

LTC and contact condition assessment

assessment

Capacitance and PF measurement Sum current

Table 5: Sample Measurements/Sensors for Power Transformers

Concluded in Part 3...

About the Author

Nicholas Abi-Samra has been actively involved in IEEE for more than 35 years. As Vice President of Asset Management at Quanta Technology, he and his team help utilities better manage and modernize their assets at lower total lifecycle cost. He was both General Chair and overall Technical Program Coordinator for the 2012 IEEE Power & Energy Society General Meeting.

Data Handling, Signal Processing and Local Expert System– Sample Requirements • Data acquisition modules with sensor interface modules to provide a common communications means to other system modules.

• A database module to provide:

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