Electrical Mirror Tablet

ELECTRICAL MIRROR January 2016

w w w. e l e c t r i c a l m i r r o r. i n

An outlook of the electrical & power industry

RNI No. DELENG/2011/39089

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Face to Face You must have observed many expensive instruments and devices for condition monitoring and protection of transformers.

It is like bringing new medicines in the market for an old disease, but not removing the root cause of old disease. What would you select between these two?

Allow the fire to happen and then quench it?.. Or not allow it to happen?

We are working on the latter.

Q Anurag Malhotra CEO in United Trafotech Pvt. Ltd. Delhi Director in GEW Trafotech Pvt. Ltd. Allahabad

Q

We are already manufacturing liquid filled transformers, which are fire safe and do not require following:

* * Why you think so that least * development has taken place in * transformer industry?

I have seen transformers manufactured in 1965 functioning today i.e after 50 years of service. How many transformers manufactured in 2010 will function in 2060? The only development which is visible is reducing the size of transformer due to availability of better raw material for economical reasons at the cost of reliability. The basic design and principle has remained un-altered.

How?

Oil filtration Breather maintenance Winding tightening Expensive fire protection systems

We do not believe in oil filtration carried-out on a transformer as a habit. Most consumers have in-correct maintenance schedules. They spoil their transformers by un-wanted oil filtration.

I know that this transformer will function healthy for the next 50 years.

Q

You said something about FRA?

We are far ahead than SFRA. This is our patented feature. Winding dislocation and its degree is reflected on control panel while the transformer is energized. So, why should anyone require FRA? Why should a transformer be under shut down when you can know the information on-line? 9 out of 10 engineers can-not read FRA.

Q

Why your transformers do not require oil filtration and winding tightening?

We neither permit atmospheric moisture entry to transformer nor allow inside generated moisture to stay in. So, transformers remain dry to a very high degree.

Winding tightening is not required as we provide auto-tightening system on windings and their shrinkage factor is attended automatically. There is no need to lift and expose the transformers in our case.

Q

You have already implemented all above. What next?

Why should a transformer be allowed to first become wet and then We earlier introduced sealed breathing system treated incorrectly to make it dry? for transformers. Now we have recently brought

Why should a transformer not be prevented to become wet during service? We are performing How you are contributing to bring that. Transformers supplied by us in 2005 have changes in the system? not been filtered once and their degree of dryness is best among a group of other make 30-35 transformers installed at same premises.

“Sealed breathing system� for OLTCs. This is first time in the world. And all our new features are not expensive. We are working on a project for use of distilled water in place of oil in transformers.

upto 132KV), REACTORS, FURNACE & BOOSTER TRANSFORMERS, METERING KIOSKS (UPTO 33KV) ,SINGLE PHASE HT TRANSFORMERS, RESIDUAL VOLTAGE TRANSFORMERS in their production range.

Recently they have developed the product COMPACT SUBSTATION (upto 2000KVA/33KV) in their product range. This is a factory assembled prefabricated s u b s t a t i o n consisting of Mr. Prashant Nankar HT switchge ar, Tr ans for me r & Managing Director, TRANSDETA TRANSFORMERS PVT.LTD. LT switchgear and connected together Transdelta is in the Transformer manufacturing with suitable sized business for last 37 years. Management is led cables & bus bars.

by Mr.P.T.NANKAR ( an IIT Graduate) & Mr. This product has Prashant Nankar (B.E.Electrical). Innovative great aesthetics, 100% ideas & enthusiastic leadership ably assisted reliability and is remarkably by the experienced staff & skilled workers has compact. The Vertical Version of given the organization an outstanding past, Compact substation has a foot print of brilliant present & shining future. only 1.5x1.5 meters with 3 meters Height for At present TRANSDELTA has various Transformers up to 200KVA.This Substation has products such as DISTRIBUTION & POWER Unique in built features such as Remote Energy TRANSFORMERS (upto 5MVA/33KV) metering system, Overload, Over current ,CURRENT & POTENTIAL TRANSFORMERS( & earth fault tripping, LT side Automatic

Power factor control with unbalanced load consideration, Transformer parameters online monitoring and SMS alerts such as Voltage, current, Power factor, Temperature, Pressure, Oil level, bus bar temperature. Because of these extraordinarily useful features, this substation is called SMART DTC (Distribution Tr a n s f o r m e r Centre).

To add a new feather to their achievements, T R A N S D E LTA has now entered in a new venture of E-commerce of Electrical equipments with an Unique Portal www.TechBaniya.com .This is an online Electrical Store with over 30,000 HT/LT installation products which can be selected using the technical parameters filters and can be ordered online. Spread over 30 categories & 100 brands, Tech Baniya is a must to have portal for any Electrical Equipment Purchaser.

Q

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February 2016

TRANSFORMERS, STAMPING & LAMINATION

Cautious Optimism in The Transformer Industry in India Now The current state of the industry Transformer Industry is one of the key segments of the ‘Electrical’ capital goods industry. This industry is also considered as the bell weather industry for many other Electrical products markets such as Capacitors, Switchgears and Insulators etc. So, from an Electrical industry perspective, it is very important to assess the state of the Transformer industry for one to get a sense of the overall Electrical Products market.

The Transformer industry in India is a highly fragmented industry with over 250+ players and the industry estimates from various bodies and experts put this estimate to be around 300-400 players depending on who is one talking with. From, our research perspective of this industry, we consider over 250+ players to be active in this industry. It is estimated that the industry capacity in India is estimated to be over 1000 GVA.

low performing state with demand stagnation. This also led to an increased price pressure and smaller players losing out closing down operations.

New hope of revival in the Industry The aggressive activities of the NDA 2 Government in the Energy sector and overall positive investment climate has led to most players feeling more hopeful on the industry prospects. Even though the actions have not led to a huge increase in order booking yet but most industry players are seeing signs of revival and expect this to open in the near future. Some key initiatives and actions that have led to this cautious optimism are: • Existing and planned projects and orders from the

As a nation our overall transformation norm stood at 7MVA/MW levels in 2008 and the policy makers had a plan to reach the levels of 11MVA/MW levels in the 12th plan. But, due to various factors and the state of DISCOMS largely, we are still hovering around the 8 to 8.5 MVA/MW levels.

Our research on this industry over the years shows that Utilities demand for Transformers is a highly important one and accounts for over 90% of the industry’s output. The remaining being the Industrial requirement of Transformers for their projects.

Over the last 2 years, the lack of new Transmission project orders, poor state of the DISCOMS and the tepid industrial activity had kept the industry in a

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• The revival of investment in being the Industrial requirement of Transformers for their projects.

Over the last 2 years, the lack of new Transmission project orders, poor state of the DISCOMS and the tepid industrial activity had kept the industry in a low performing state with demand stagnation. This also led to an increased price pressure and smaller players losing out closing down operations.

New hope of revival in the Industry The aggressive activities of the NDA 2 Government in the Energy sector and overall positive investment climate has led to most players feeling more hopeful on the industry prospects. Even though the actions have not led to a huge increase in order booking yet but most industry players are seeing signs of revival and expect this to open in the near future. Some key initiatives and actions that have led to this cautious optimism are: • Existing and planned projects and orders from the RE projects in India – Solar Parks and Projects and Wind projects

This industry has been under a rough weather over the last 2 years with a demand stagnation in India. This industry is estimated to be stagnating between 250,000 to 280,000 MVA for the last 2 years and recently showing some signs of growth.

In terms of sales by products, the Power Transformers in MVA terms is clearly over 70% of this market while Distribution Transformers account for over 30% of the market in MVA terms but could show a reverse trend when we talk in terms of number of Units. The industry is governed by mostly the Oil Filled Transformer industry and Dry Type of transformers (only in DTR space) have not yet gained full acceptance due to their high costs. Copper windings still account for a major portion of the industry, while Aluminum windings are mostly limited to < 250 kVA levels.

more effectively.

• The opening up of new transmission projects and the de-bottlenecking of old stuck projects has led to order wins by many firms in the recent past for the Power Transformers.

•The upcoming new transmission projects and the Green Energy Corridors will see more uptick in the Power Transformer Segment going forward.

RE projects in India – Solar Parks and Projects and Wind projects • The opening up of new transmission projects and the de-bottlenecking of old stuck projects has led to order wins by many firms in the recent past for the Power Transformers.

• The upcoming new transmission projects and the Green Energy Corridors will see more uptick in the Power Transformer Segment going forward.

• The announcement of UDAY and the participation of 15 states already in the program has given many players some hope that the fiscal conditions of DISCOM’s would improve and this would lead to more aggressive DTR purchases in the next few years to reduce the losses.

• Even though the Government had announced 2 major schemes of Integrated Power Development Scheme (IPDS for the Urban areas) and Deendayal Upadhyaya Gram Jyoti Yojana (DDUGJY for the Rural areas), nothing of note till now has been seen on ground from these schemes. But now, with UDAY being implemented in many states, this will provide a framework for most utilities to absorb the additional investments in IPDS and DDYGJY programs and implement them on the ground

•The announcement of UDAY and the participation of 15 states already in the program has given many players some hope that the fiscal conditions of DISCOM’s would improve and this would lead to more aggressive DTR purchases in the next few years to reduce the losses.

• Even though the Government had announced 2 major schemes of Integrated Power Development Scheme (IPDS for the Urban areas) and Deendayal Upadhyaya Gram Jyoti Yojana (DDUGJY for the Rural areas), nothing of note till now has been seen on ground from these schemes. But now, with UDAY being implemented in many states, this will provide a framework for most utilities to absorb the additional investments in IPDS and DDYGJY programs and implement them on the ground more effectively.

• The revival of investment in manufacturing and new CAPEX investments due to ‘Make in India’ has not yet happened but most industry players are cautiously optimistic about the same.

Rudranil Roysharma

Senior Consultant Energy Vertical Feedback Consulting Services Private Limited

rudranil@feedbackconsulting.com

www.feedbackconsulting.com

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CAPACITOR & CONDENSER

A Detailed Study on Shunt Capacitor Bank Fundamentals and Protection INTRODUCTION Shunt capacitor banks (SCB) are mainly installed to provide capacitive reactive compensation/ power factor correction.

The use of SCBs has increased because t h e y a re re l at i ve l y inexpensive, easy and quick to install and can be deployed virtually anywhere in the network. Its installation has other beneficial effects on the system such as: improvement of the voltage at the load, better voltage regulation (if they were adequately designed), reduction of losses and reduction or postponement o f i nv e s t m e n t s i n transmission. The main disadvantage of SCB is that its reactive power output is proportional to the square of the voltage and consequently when the voltage is low and the system need them most, they are the least efficient.

Shunt capacitor banks are used to improve the quality of the electrical supply and the efficient operation of the power system. Studies show that a flat voltage profile on the system can significantly reduce line losses. Shunt capacitor banks are relatively inexpensive and can be easily installed anywhere on the network.

This paper reviews principles of shunt capacitor bank design for substation installation and basic protection techniques.

The protection of shunt capacitor bank includes: a) protection against internal bank faults and faults that occur inside the capacitor unit; and, b) protection of the bank against system disturbances.

THE C A PA C I T O R UNIT AND BANK CONFIGURATIONS 2.1 The Capacitor Unit The capacitor unit, Fig. 1, is the building block of a shunt capacitor bank.

The capacitor unit is made up of individual c a p a c i to r e l e m e nt s, arranged in parallel/ series connected groups, within a steel enclosure.

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The internal discharge device is a resistor that reduces the unit residual voltage to 50V or less in 5 min. Capacitor units are available in a variety of voltage ratings (240 V to 24940V) and sizes (2.5 kvar to about 1000 kvar).

2.1.1 Capacitor unit capabilities

up to 135%of rated reactive power caused by the combined effects of: Voltage in excess of the nameplate rating at fundamental frequency, but not over 110% of rated rms voltage.

Harmonic voltages superimposed on the fundamental frequency.

Reactive power manufacturing tolerance of up to 115% of rated reactive power.

2.2 Bank Configurations Relay protection of shunt capacitor banks requires The use of fuses for protecting the capacitor units some knowledge of and it location (inside the capacitor unit on each the capabilities and element or outside the unit) is an important subject in the design of limitations of SCBs. They also the capacitor affect the failure unit and mode of the associated capacitor unit electrical and influence equipment the design including: of the bank individual protection. capacitor unit, Depending on bank switching the application d e v i c e s , any of the fuses, voltage following and current configurations s e n s i n g are suitable for d e v i c e s . shunt capacitor Capacitors are banks: intended to be operated at or below their rated Fig 1 â&#x20AC;&#x201D; The capacitor Unit voltage and frequency as they are very sensitive to these values; INTRODUCTION the reac tive power Shunt capacitor banks (SCB) are mainly installed to generated by a capacitor provide capacitive reactive compensation/power is proportional to both factor correction. The use of SCBs has increased of them (kVar - 27c f V 2). because they are relatively inexpensive, easy and quick The IEEE Std 18-1992 and to install and can be deployed virtually anywhere Std 1036-1992 specify in the network. Its installation has other beneficial the standard ratings of effects on the system such as: improvement of the the capacitors designed voltage at the load, better voltage regulation (if for shunt connection they were adequately designed), reduction of losses to ac systems and also and reduction or postponement of investments p rov i d e a p p l i c at i o n in transmission. The main disadvantage of SCB is guidelines. that its reactive power output is proportional to the square of the voltage and consequently when T h e s e s t a n d a r d s the voltage is low and the system need them most, stipulate that: they are the least efficient.

Capacitor units should be capable of continuous Shunt capacitor banks are used to improve the operation up to 110% quality of the electrical supply and the efficient of rated terminal rms operation of the power system. Studies show that voltage and a crest a flat voltage profile on the system can significantly voltage not exceeding reduce line losses. Shunt capacitor banks are 1.2 x .\12 of rated rms relatively inexpensive and can be easily installed voltage, i n c l u d i n g anywhere on the network. harmonics but excluding This paper reviews principles of shunt capacitor transients. The capacitor bank design for substation installation and basic should also be able to protection techniques. The protection of shunt carry 135% of nominal capacitor bank includes: a) protection against current. internal bank faults and faults that occur inside Capacitors units should not give less than 100% nor more than 115% of rated reactive power at rated sinusoidal voltage and frequency.

the capacitor unit; and, b) protection of the bank against system disturbances.

Capacitor units should be suitable for continuous operation at

The capacitor unit, Fig. 1, is the building block of a shunt capacitor bank. The capacitor unit is made up of individual capacitor elements, arranged in parallel/ series connected groups, within a steel

T H E C A PAC I TO R CONFIGURATIONS

UNIT

AND

BANK

2.1 The Capacitor Unit

enclosure. The internal discharge device is a resistor that reduces the unit residual voltage to 50V or less in 5 min. Capacitor units are available in a variety of voltage ratings (240 V to 24940V) and sizes (2.5 kvar to about 1000 kvar).

2.1.1 Capacitor unit capabilities Relay protection of shunt capacitor banks requires some knowledge of the capabilities and limitations of the capacitor unit and associated electrical equipment including: individual capacitor unit, bank switching devices, fuses, voltage and current sensing devices. Capacitors are intended to be operated at or below their rated voltage and frequency as they are very sensitive to these values; the reactive power generated by a capacitor is proportional to both of them (kVar - 27c f V 2). The IEEE Std 18-1992 and Std 1036-1992 specify the standard ratings of the capacitors designed for shunt connection to ac systems and also provide application guidelines.

These standards stipulate that: Capacitor units should be capable of continuous operation up to 110% of rated terminal rms voltage and a crest voltage not exceeding 1.2 x .\12 of rated rms voltage, including harmonics but excluding transients. The capacitor should also be able to carry 135% of nominal current.

Capacitors units should not give less than 100% nor more than 115% of rated reactive power at rated sinusoidal voltage and frequency.

Capacitor units should be suitable for continuous operation at up to 135%of rated reactive power caused by the combined effects of: Voltage in excess of the nameplate rating at fundamental frequency, but not over 110% of rated rms voltage.

Harmonic voltages superimposed on the fundamental frequency.

Reactive power manufacturing tolerance of up to 115% of rated reactive power.

2.2 Bank Configurations The use of fuses for protecting the capacitor units and it location (inside the capacitor unit on each element or outside the unit) is an important subject in the design of SCBs. They also affect the failure mode of the capacitor unit and influence the design of the bank protection. Depending on the application any of the following configurations are suitable for shunt capacitor banks: a) Externally Fused An individual fuse, externally mounted between the capacitor unit and the capacitor bank fuse bus, typically protects each capacitor unit. The capacitor unit can be designed for a relatively high voltage because the external fuse is capable of interrupting a high-voltage fault. Use of capacitors with the highest possible voltage rating will result in a capacitive bank with the fewest number of series groups. A failure of a capacitor element welds the foils together and short circuits the other capacitor elements connected in parallel in the same group.

The remaining capacitor elements in the unit remain in service with a higher voltage across them than before the failure and an increased in capacitor unit current. If a second element fails the process repeats itself resulting in an even higher voltage for the remaining elements. Successive failures within the same unit will make the fuse to operate, disconnecting the capacitor unit and indicating the failed one.

Externally fused SCBs are configured using one or more series groups of parallel-connected www. electricalmirror.in

capacitor units per phase (Fig. 2). The available unbalance signal level decreases as the number of series groups of capacitors is increased or as the number of capacitor units in parallel per series group is increased. However, the kiloVar rating of the individual capacitor unit may need to be smaller

is shortened and the voltage on the remaining elements is 48/47 or about a 2% increase in the voltage. The capacitor bank continues in service; however, successive failures of elements will lead to the removal of the bank.

Fig. 2 — Externally fused shunt capacitor bank and capacitor unit

complete unit is not expected to fail.

Fuseless Shunt Capacitor Banks Fig 3 — Internally fused shunt capacitor bank and capacitor unit because a minimum number of parallel units are required to allow the bank to remain in service with one fuse or unit out. b) Internally Fused Each capacitor element is fused inside the capacitor unit. The fuse is a simple piece of wire enough to limit the current and encapsulated in a wrapper able to withstand the heat produced by the arc.

Upon a capacitor element failure, the fuse removes the affected element only. The other elements, connected in parallel in the same group, remain in service but with a slightly higher voltage across them. Fig. 3 illustrates a typical capacitor bank utilizing internally fused capacitor units. In general, banks employing internally fused capacitor units are configured with fewer capacitor units in parallel and more series groups of units than are used in banks employing externally fused capacitor units.

The capacitor units are normally large because a

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The capacitor units for fuseless capacitor banks are identical to those for externally fused described above. To form a bank, capacitor units are connected in series strings between phase and neutral, shown in Fig. 4.

The protection is based on the capacitor elements (within the unit) failing in a shorted mode, shortcircuiting the group. When the capacitor element fails it welds and the capacitor unit remains in ser vice.

The voltage a c r o s s the failed capacitor element is Fig 4 — Fuseless shunt capacitor then shared bank and series string among all the remaining capacitor element groups in the series. For example, is there are 6 capacitor units in series and each unit has 8 element groups in series there is a total of 48 element groups in series. If one capacitor element fails, the element

The fuseless design is not usually applied for system voltages less than about 34.5 kV. The reason is that there shall be more than 10 elements in series so that the bank does not have to be removed from service for the failure of one element because the voltage across the remaining elements would increase by a factor of about E (E — 1), where E is the number of elements in the string. The discharge energy is small because no capacitor units are connected directly in parallel. Another advantage of fuseless banks is that the unbalance protection does not have to be delayed to coordinate with the fuses. d) Unfused Shunt Capacitor Banks Contrary to the fuseless configuration, where the units are connected in series, the unfused shunt capacitor bank uses a series/parallel connection of the capacitor units. The unfused approach would normally be used on banks below 34.5 kV, where series strings of capacitor units are not practical, or on higher voltage banks with modest parallel energy.

This design does not require as many capacitor units in parallel as an externally fused bank.

3. CAPACITOR BANK DESIGN The protection of shunt capacitor banks requires understanding the basics of capacitor bank design and capacitor unit connections. Shunt capacitors banks are arrangements of series/ paralleled connected units. Capacitor units connected in paralleled make up a group and series connected groups form a single-phase capacitor bank. As a general rule, the minimum number of units connected in parallel is such that isolation of one capacitor unit in a group should not cause a voltage

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unbalance sufficient to place more than 110% of rated voltage on the remaining capacitors of the group. Equally, the minimum number of series connected groups is that in which the complete bypass of the group does not subject the others remaining in service to a permanent overvoltage of more than 110%.

The maximum number of capacitor units that may be placed in parallel per group is governed by a different consideration. When a capacitor bank unit fails, other capacitors in the same parallel group contain some amount of charge. This charge will drain off as a high frequency transient current that flows through the failed capacitor unit and its fuse.

The fuse holder and the failed capacitor unit should withstand this discharge transient.

The discharge transient from a large number of paralleled capacitors can be severe enough to rupture the failed capacitor unit or the expulsion fuse holder, which may result in damage to adjacent units or cause a major bus fault within the bank. To minimize the probability of failure of the expulsion fuse holder, or rupture of the capacitor case, or both, the standards impose a limit to the total maximum energy stored in a paralleled connected group to 4659 kVar. In order not to violate this limit, more capacitor groups of a lower voltage rating connected in series with fewer units in parallel per group may be a suitable solution. However, this may reduce the sensitivity of the unbalance detection scheme.

Splitting the bank into 2 sections as a double Y may be the preferred solution and may allow for better unbalance detection scheme. Another possibility is the use of current limiting fuses.

The optimum connection for a SCB depends on the best utilization of the available voltage ratings of capacitor units, fusing, and protective relaying.

Virtually all substation banks are connected wye.

Distribution capacitor banks, however, may be connected wye or delta. Some banks use an H configuration on each of the phases with a current transformer in the connecting branch to detect the unbalance.

3.1 Grounded Wye-Connected Banks Grounded wye capacitor banks are composed of series and parallel-connected capacitor units per phase and provide a low impedance path to ground.

Fig. 5 shows typical bank arrangements.

Advantages of the grounded capacitor banks include: • Its low-impedance path to ground provides inherent self-protection for lightning surge currents and gives some protection from surge voltages. Banks can be operated without surge arresters taking advantage of the capability of the capacitors to absorb the surge.

• Offer a low impedance path for high frequency currents and so they can be used as filters in systems with high harmonic content. However, caution shall be taken to avoid resonance between the SCB and the system.

• Reduced transient recovery voltages for circuit breakers and other switching equipment.

Some drawbacks for grounded wye SCB are: • Increased interference on telecom circuits due to harmonic circulation.

• Circulation of inrush currents and harmonics may cause misoperations and/or over-operation on protective relays and fuses.

• Phase series reactors are required to reduce voltages appearing on the CT secondary due to the effect of high frequency, high amplitude currents.

Multiple Units in Series Phase to Ground — Double Wye When a capacitor bank becomes too large, making the parallel energy of a series group too great (above 4650 kvar) for the capacitor units or fuses, the bank may be split into two wye sections. The characteristics of the grounded double wye are similar to a grounded single wye bank. The two

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neutrals should be directly connected with a single connection to ground.

Multiple units grounded single Wye

rated at line-to-line voltage. With only one series group of units no over voltage occurs across the remaining capacitor units from the isolation

Multiple units grounded single Wye

Fig. 5 - Grounded Wye Shunt Capacitor Banks The double Wye design allows a secure and faster unbalance protection with a simple uncompensated relay because any system zero sequence component affects both wyes equally, but a failed capacitor unit will appear as un unbalanced in the neutral. Time coordination may be required to allow a fuse, in or on a failed capacitor unit, to blow. If it is a fuseless design, the time delay may be set short because no fuse coordination is required. If the current through the string exceeds the continuous current capability of the capacitor unit, more strings shall be added in parallel.

3.2 Ungrounded Wye-Connected Banks Typical bank arrangements of ungrounded Wye SCB are shown in Fig. 6. Ungrounded wye banks do not permit zero sequence currents, third harmonic currents, or large capacitor discharge currents during system ground faults to flow. (Phase-tophase faults may still occur and will result in large discharge currents). Other advantage is that over voltages appearing at the CT secondaries are not as high as in the case of grounded banks. However, the neutral should be insulated for full line voltage because it is momentarily at phase potential when the bank is switched or when one capacitor unit fails in a bank configured with a single group of units. For banks above 15kV this may be expensive. a) Multiple Units in Series Phase to Neutral Single Wye Capacitor units with external fuses, internal fuses, or no fuses (fuseless or unfused design) can be used to make up the bank. For unbalance protection schemes that are sensitive to system voltage unbalance, either the unbalance protection time delay shall be set long enough for the line protections to clears the system ground faults or the capacitor bank may be allowed to trip off for a system ground fault. b) Multiple units in series phase to neutral-double wye When a capacitor bank becomes too large for the maximum 4650 kvar per group the bank may be split into two wye sections. When the two neutrals are ungrounded, the bank has some of the characteristics of the ungrounded single-wye bank.

These two neutrals may be tied together through a current transformer or a voltage Transformer as for any ungrounded why bank, the neutral instrument transformers should be insulated from ground for full line-to-ground voltage, as should the phase terminals.

of a faulted capacitor unit. Therefore, unbalance detection is not required for protection and they are not treated further in this paper.

3.4 H Configuration Some larger banks use an H configuration in each phase with a current transformer connected between the two legs to compare the current down each leg.

As long as all capacitors are normal, no current will flow through the current transformer. If a capacitor fuse operates, some current will flow through the current transformer. This bridge connection can be very sensitive. This arrangement is used on large banks with many capacitor units in parallel.

4. CAPACITOR BANK PROTECTION The protection of SCB’s involves: a) protection of the bank against faults occurring within the bank including those inside the capacitor unit; and, b) protection of the bank against system disturbances and faults. This paper only discusses relay based protection schemes that provide alarm to indicate an unbalance within the bank and initiate a shutdown of the bank in case of faults that may lead to catastrophic failures. It does not deal with the means and strategies to protect individual elements or capacitor units. The protection selected for a capacitor bank depends on bank configuration, whether or not the capacitor bank is grounded and the system grounding.

4.1 Capacitor Unbalance Protection The protection of shunt capacitor banks against internal faults involves several protective devices/ elements in a coordinated scheme. Typically, the protective elements found in a SCB for internal faults are: individual fuses (not discuss in this paper), unbalance protection to provide alarm/ trip and over current elements for bank fault protection.

Removal of a failed capacitor element or unit by its fuse results in an increase in voltage across the remaining elements/ units causing an unbalance within the bank. A continuous over voltage (above 1.1 pu) on any unit shall be prevented by means of protective relays that trip the bank. Unbalance protection normally senses changes associated with the failure of a capacitor element or unit and removes the bank from service when the resulting over voltage becomes excessive on the remaining healthy capacitor units.

Unbalance protection normally provides the primary protection for arcing faults within a capacitor bank and other abnormalities that may damage capacitor elements/ units. Arcing faults may cause substantial damage in a small fraction of a second.

Multiple units ungrounded single Wye Multiple units ungrounded double Wye 3.3 Delta-connected Banks Delta- connected banks are generally used only at distributions voltages and are configured with a single series group of capacitors

Fig. 6 - Ungrounded Wye Shunt Capacitor Banks www. electricalmirror.in

The unbalance protection should have minimum intentional delay in order to minimize the amount of damage to the bank in the event of external arcing.

In most capacitor banks an external arc within the capacitor bank does not result in enough change in the phase current to operate the primary fault protection (usually an over current relay) The sensitivity requirements for adequate capacitor bank protection for this condition may be very demanding, particularly for SBC with many series groups. The need for sensitive resulted in the development of unbalance protection where certain voltages or currents parameters of the capacitor bank are monitored and compared to the bank balance conditions.

canceling failures occur.

Undetectable Faults For certain capacitor bank configurations some faults within the bank will not cause an unbalance signal and will go undetected. For example: a) rack-to-rack faults for banks with two series groups connected phase-over-phase and using neutral voltage or current for unbalance protection; and,b) rack-to-rack faults for certain H-bridge connections.

In practice, the unbalance seen by the unbalance relay is the result of the loss of individual capacitor units or elements and the inherent system and bank unbalances. The primary unbalance, which exists on

For an efficient unbalance protection it is important to understand the failure mode of the capacitor

Internally fused capacitors have individual fused capacitor elements that are disconnected when an element breakdown occurs (the element fails opened). The risk of successive faults is minimized because the fuse will isolate the faulty element within a few cycles. The degree of unbalance introduced by an element failure is less than that which occurs with externally fused units (since the amount of capacitance removed by blown fuse is less) and hence a more sensitive unbalance protection scheme is required when internally fused units are used.

Schemes with Ambiguous Indication A combination of capacitor elements/ units failures may provide ambiguous indications on the conditions of the bank. For instance, during steady state operation, negligible current flows through the current transformer between the neutrals of an ungrounded wye-wye capacitor bank for a balanced bank, and this condition is correct. However, the same negligible current may flow through this current transformer if an equal number of units or elements are removed from the same phase on both sides of the bank (Fig. 7). This condition is undesirable, and the indication is obviously ambiguous.

Where ambiguous indication is a possibility, it is desirable to have a sensitive alarm (preferably one fuse operation for fused banks or one faulted element for fuseless or unfused banks) to minimize the probability of continuing operation with canceling failures that result in continuing, undetected over voltages on the remaining units.

It may also be desirable to set the trip level based on an estimated number of canceling failures in order to reduce the risk of subjecting capacitor units to damaging voltages and requiring fuses to operate above their voltage capability when www. electricalmirror.in

Fig. 9 (a)

Fig. 9 (b)

a) Unbalance Protection for Ungrounded Single Wye Banks The simplest method to detect unbalance in single ungrounded Wye banks is to measure the bank neutral or zero sequence voltage. If the capacitor bank is balanced and the system voltage is balance the neutral voltage will be zero. A change in any phase of the bank will result in a neutral or zero sequence voltage.

Capacitor Element Failure Mode

element. In externally fused, fuseless or unfused capacitor banks, the failed element within the can is short-circuited by the weld that naturally occurs at the point of failure (the element fails shortcircuited). This short circuit puts out of service the whole group of elements, increasing the voltage on the remaining groups. Several capacitor elements breakdowns may occur before the external fuse (if exists) removes the entire unit. The external fuse will operate when a capacitor unit becomes essentially short circuited, isolating the faulted unit.

4.1.1 Unbalance Protection Methods for Ungrounded Wye Banks

Inherent Unbalance and System Unbalance

Capacitor unbalance protection is provided in many different ways, depending on the capacitor bank arrangement and grounding. A variety of unbalance protection schemes are used for internally fused, externally fused, fuseless, or unfused shunt capacitor.

Fig. 7 â&#x20AC;&#x201C; Compensating failures in the same phase result in no unbalance signal

alarm condition based on an idealized bank. The alarm should have sufficient time delay to override external disturbances.

Fig. 8 (a) shows all capacitor bank installations (with or without fuses), is due to system voltage unbalance and capacitor manufacturing tolerance. Secondary unbalance errors are introduced by sensing device tolerances and variation and by relative changes in capacitance due to difference in capacitor unit temperatures in the bank. If the inherent unbalance error approaches 50% of the alarm setting, compensation should be provided in order to correctly alarm for the failure of one unit or element as specified. In some cases, a different bank connection can improve the sensitivity without adding compensation. For example, a wye bank can be split into a wye-wye bank, thereby doubling the sensitivity of the protection and eliminating the system voltage unbalance effect. A neutral unbalance protection method with compensation for inherent unbalance is normally required for very large banks. The neutral unbalance signal produced by the loss of one or two individual capacitor units is small compared to the inherent unbalance and the latter can no longer be considered negligible. Unbalance compensation should be used if the inherent unbalance exceeds one half of the desired setting. Harmonic voltages and currents can influence the operation of the unbalance relay unless power frequency band-pass or other appropriate filtering is provided.

a method that measures the voltage between capacitor neutral and ground using a VT and an over voltage relay with 3th harmonic filter. It is simple but suffers in presence of system voltage unbalances and inherent unbalances. The voltage -sensing device is generally a voltage transformer Fig. 10 but it could be Compensated Neutral Voltage Unbala capacitive ance method potential device or resistive potential device. The voltage-sensing device should be selected for the lowest voltage ratio attainable, while still being able to withstand transient and continuous over voltage conditions to obtain the maximum unbalance detection sensitivity. However, a voltage transformer used in this application should be rated for full system voltage because the neutral voltage can under some conditions rise to as high as 2.5 per unit during switching.

An equivalent zero sequence component that eliminate the system unbalances can be derived Unbalance Trip Relay Considerations utilizing three voltage-sensing devices with their The time delay of the unbalance relay trip should be high side voltage wye-connected from line to minimized to reduce damage from an arcing fault ground, and the secondaries connected in a broken within the bank structure and prevent exposure delta. The voltage source VTs can be either at a tap in of the remaining capacitor units to over voltage the capacitor bank or used the VTs of the bank bus.

Figs. 8 (b) shows a neutral unbalance relay protection conditions beyond their permissible limits. scheme for an ungrounded wye capacitor bank, The unbalance trip relay should have enough time using three phase-to-neutral voltage transformers delay to avoid false operations due to inrush, system with their secondaries connected in broken delta to ground faults, switching of nearby equipment, and an over voltage relay. Compared to the scheme in non-simultaneous pole operation of the energizing Fig. 8(a), this scheme has the advantage of not being switch. For most applications, 0.1s should be sensitive to system voltage unbalance. Also, the adequate. For unbalance relaying systems that would unbalance voltage going to the over voltage relay is operate on a system voltage unbalance, a delay three times the neutral voltage as obtained from Fig slightly longer than the upstream protection 8(a). For the fault clearing time is required to avoid tripping same voltage due to a system fault. Longer delays increase t ra n s fo r m e r the probability of catastrophic bank failures. ratio, there is a gain With grounded capacitor banks, the failure of three in of one pole of the SCB switching device or Fig.11 (a) Fig. 11 (b) sensitivity a single phasing from a blown bank fuse will over the allow zero sequence currents to flow in system s i n g l e ground relays. Capacitor bank relaying, including the neutral-to-ground voltage transformer scheme. The operating time of the switching device, should be voltage transformers should be rated for line-to-line coordinated with the operation of the system ground voltage. relays to avoid tripping system load. The unbalance trip relay scheme should have a lockout feature to Modern digital relays can calculate the zero sequence prevent inadvertent closing of the capacitor bank voltage from the phase voltages as shown in Fig switching device if an unbalance trip has occurred. 9 (a), eliminating the need of additional auxiliary VTs to obtain the zero sequence voltage. Fig 9 (b) t) Unbalance Alarm Relay Considerations shows the same principle but using the VTs on the To allow for the effects of inherent unbalance capacitor bank bus. Although schemes shown in Fig within the bank, the unbalance relay alarm should 8(b), 9(a) and 9(b) eliminate system unbalances, they be set to operate at about one-half the level of do not eliminate the inherent capacitor unbalance. the unbalance signal determined by the calculated Fig. 10 shows a protection scheme that removes the

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system unbalance and compensate for the inherent capacitor unbalance. It is a variation of the voltage differential scheme for grounded banks described in section 4.1.2 c). The best method to eliminate the system unbalance is to split the bank in two Wyes; however, it may not be always possible or desirable. The system unbalance appears as a zero sequence voltage both at the bank terminal and at the bank neutral. The bank terminal zero sequence component is derived from 3 line VTs with their high side Wye connected and their secondaries connected in broken delta. The difference voltage between the neutral unbalance signal due to system unbalance and the calculated zero sequence from the terminal VTs will be compensated for all conditions of system unbalance. The remaining error appearing at the neutral due to manufacturers capacitor tolerance is then compensated for by means of a phase shifter. b) Unbalance Protection for Ungrounded Double Wye Banks Ungrounded banks can be split into two equal banks.

This bank configuration inherently compensates for system voltage unbalances; however, the effects of manufacturers capacitor tolerance will affect relay operation unless steps are taken to compensate for this error.

Fig. 13 (a)

Fig. 13(b)

Three methods of providing unbalance protection for double wye ungrounded banks are presented. Fig. 11(a) uses a current transformer on the connection of the two neutrals and an over current relay (or a shunt and a voltage relay). Fig. 11(b) uses a voltage transformer connected between the two neutrals and an over voltage relay. The effect of system voltage unbalances are avoided by both schemes, and both are unaffected by third harmonic currents or voltages when balanced. The current transformer or voltage transformer should be rated for system voltage.

The neutral current is one-half of that of a single grounded bank of the same size. However, the current transformer ratio and relay rating may be selected for the desired sensitivity because they are not subjected to switching surge currents or single-phase currents as they are in the grounded neutral scheme.

Although a low-ratio voltage transformer would be desirable, a voltage transformer rated for system voltage is required for the ungrounded neutral.

Therefore, a high turns ratio should be accepted.

current to flow in the neutral. Fig. 13 (a) shows a protection based on a current transformer installed on the connection between the capacitor bank neutral and ground. This current transformer has unusual high over voltage and current requirements.

The ratio is selected to give both adequate over current capability and appropriate signal for the protection. The current transformer output has a burden resistor and a sensitive voltage relay. Because of the presence of harmonic currents (particularly the third, a zero sequence harmonic that flows in the neutral-to-ground connection), the relay should be tuned to reduce its sensitivity to frequencies other than the power frequency.

The voltage differential provides a very sensitive and efficient method to compensate for both system and inherent capacitor bank unbalances in grounded wye capacitor banks. Fig. 16 shows the voltage differential scheme for a single wye-connected bank and Fig. 16 for a double wye­connected bank.

The voltage across the burden resistor is in phase with the neutral-to-ground current. This neutralto-ground current is the vector sum of the threephase currents, which are 90° out of the phase with the system phase-to-ground voltages. This scheme may be compensated for power system voltage unbalances, by accounting for the 90° phase shift, and is not unusually appropriate for very large capacitor banks requiring very sensitive settings. Each time the capacitor bank is energized, momentary unbalanced capacitor charging currents will circulate in the phases and in the capacitor neutral. Where a parallel bank is already in service these current can be on the order of thousands Amps causing the relay to maloperate and CT to fail.

The capacitor bank tap voltage is obtained by connecting a voltage-sensing device across the ground end parallel group (or groups) of capacitors. This may be a midpoint tap, where the voltage is measured between the midpoint of the phase and ground. Alternatively, the tap voltage may be measured across low-voltage capacitors (that is, a capacitive shunt) at the neutral end of the phase.

Fig.13 (a) presents an unbalance voltage protection scheme for single grounded wye connected SCB’s using capacitor tap point voltages. Modern digital relays use the calculated zero sequence voltage instead as shown in Fig. 13(b). b) Unbalance Protection for Grounded Double Wye Banks Fig. 14 shows a scheme where a current transformer is installed on each neutral of the two sections of a double Why SCB. The neutrals are connected to a common ground.

The current transformer s e co n d a r i e s a re cross-connected to an over current

Fig. 14 relay so that the relay is insensitive to any outside condition that affects both sections of the capacitor bank in the same direction or manner. The current transformers can be subjected to switching transient currents and, therefore, surge protection is required. They should be sized for single-phase load currents if possible. (Alternatively, the connections from neutral to ground from the two wyes may be in opposite directions through a single-window current transformer). c) Voltage differential protection method for grounded wye banks On large S C B s w i t h l a r g e number o f capacitor units, it is very difficult to detect Fig. 15 — Voltage Differential Scheme for the loss Grounded Single Wye SCB of 1

Fig. 12 shows a scheme where the neutrals of the two capacitor sections are ungrounded but tied together. A voltage transformer, or potential device, is used to measure the voltage between the capacitor bank neutral and ground. The relay should have a harmonic filter.

4.1.2 Unbalance Protection Methods for Grounded Wye Banks a) Unbalance Protection for Grounded Single Wye Banks An unbalance in the capacitor bank will cause

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Fig. 16 — Voltage Differential Scheme for Grounded Double Wye SCB

or 2 capacitor units as the signal produced by the unbalance is buried in the inherent bank unbalance.

The scheme uses two voltage transformers per phase: one connected to a tap on the capacitor bank; the other, at the bank bus for single Wye banks; or, for double Wye banks, at a similar tap on the second bank. By comparing the voltages of both VTs, a signal responsive to the loss of individual capacitor elements or units is derived.

For commissioning, after checking that all capacitors are good and no fuses have operated, the voltage levels are initially adjusted to be equal. The initial difference signal between the capacitor bank tap voltage and the bus voltage (for single Wye banks) signals is zero, and the capacitor tolerance and initial system voltage unbalance is compensated. If the system voltage unbalance should vary, the relay system is still compensated because a given percent change in bus voltage results in the same percent change on the capacitor bank tap. Any subsequent voltage difference between capacitor tap voltage and bus voltage will be due to unbalances caused by loss of capacitor units within that particular phase.

For double Wye banks, the tap voltage is compared the other Wye tap voltage.

Modern digital relay dynamically compensate secondary errors introduced by sensing device variation and temperature differences between capacitor units within the bank.

If the bank is tapped at the midpoint the sensitivity is the same for failures within and outside the tapped portion. If the bank is tapped below (above) the midpoint, the sensitivity for failures within the tapped portion will be greater (less) than for failures outside the tap portion. This difference may cause difficulty in achieving an appropriate relay setting. The sensitivity for a midpoint tap and a tap across low-voltage capacitors at the neutral end of the phase is the same. Tapping across the bottom series groups or a midpoint tap is not appropriate for fuseless banks with multiple strings because the strings are not connected to each other at the tap point. Tapping across the low-voltage capacitors is suitable for fuseless capacitor banks.

4.2 Protection against Other Internal Bank Faults The are certain faults within the bank that the unbalance protection will not detect or other means are required for its clearance.

Mid-Rack Phase to Phase Faults Usually individual phases of a SCB are built on separate structures where phase to phase faults are unlikely. However, consider an ungrounded single Wye capacitor bank with two series groups per phase where all three phases are installed Fig. 17 — Mid-rack Fault upon a single steel structure. A mid-rack fault between 2 phases as shown in Fig. 17 is possible and will go undetected. This fault does not cause an unbalance of the neutral voltage (or neutral current if grounded) as the healthy voltage is counter balance by the 2 other faulty phase voltages.

The most efficient protection for mid-rack phase to phase faults is the negative sequence current.

Tripping shall be delayed to coordinate with other relays in the system. www. electricalmirror.in

Faults on the Capacitor Bank Bus

4.4 Relays for Bank Closing Control

Time overcurrent relays for phase and ground are required to provide protection for phase and ground faults on the connecting feeder (or buswork) between the bank bus and the first capacitor unit.

Directional overcurrent relays looking into the bank are preferred to avoid maloperation of the TOC 51 N for unbalance system faults.

Once disconnected from the system a shunt capacitor bank cannot be re-inserted immediately due to the electrical charge trapped within the capacitor units, otherwise catastrophic damage to the circuit breaker or switch can occur. To accelerate the discharge of the bank, each individual capacitor unit has a resistor to discharge the trapped charges within 5min. Undervoltage or undercurrent relays with timers are used to detect the bank going out of service and prevent closing the breaker until the set time has elapsed.

4.3 Protection of the SCB against System Disturbances and Faults 4.3.1 System Overvoltage Protection The capacitor bank may be subjected to overvoltages resulting from abnormal system operating conditions. If the system voltage exceeds the capacitor capability the bank should be removed from service.

The removal of the capacitor bank lowers the voltage in the vicinity of the bank reducing the overvoltage on other system equipment. Time delayed or inverse time delayed phase overvoltage relays are used.

5. CONCLUSIONS The protection of shunt capacitor banks uses simple, well known relaying principles such as overvoltage, overcurrents. However, it requires the protection engineer to have a good understanding of the capacitor unit, its arrangement and bank design issues before embarking in its protection. Unbalance is the most important protection in a shunt capacitor

bank, as it provides fast and effective protection to assure a long and reliable life for the bank. To accomplish its goal, unbalance protection requires high degree of sensitivity that might be difficult to achieve. The main concepts for the design of a shunt capacitor bank and its protection have been reviewed in the paper. The latest IEEE Guide for the Protection of Shunt Capacitors Banks shall be the guiding document when implementing a protection scheme to a shunt capacitor bank.

Dr. L.Ashok Kumar has completed his B.E., ME., MBA., PhD). He has both teaching and industrial experience of 17 years. At present he is working as a Professor in the Dept. of EEE, PSG College of Technology, Coimbatore. He has got 16 research projects from various Government funding agencies. He has published 75 Technical papers in reputed National and International Journals and presented 71 technical articles in International and National Conferences. He is a recipient of many National and International Awards. He is a member of various National & International Technical bodies like ISTE, IETE, TSI, BMSI, ISSS, SESI, SSI CSI & TAI.

element14 adds thousands of Maxim Integrated Products to its global franchise element14 will add thousands of integrated circuits (ICs) from Silicon Valley-based Maxim Integrated Products, Inc., to its franchise. With this new stock from Maxim, element14 will offer a variety of ICs for research and design applications. With expertise in power management ICs, Maxim offers high-performance analog and mixed-signal engineering solutions. Maxim’s analog integration capabilities provide seamless functionality and a host of design features to support ease of installation and versatile application for a wide range of technologies and projects. These include industrial systems, medical devices, and data center equipment, as well as mobile devices and automobiles. The new agreement fosters a commitment between the companies, with a goal of enhancing the range of product offerings over time. element14 offers products to support prototyping and early stage design with next-day delivery available on all products. “Our new global partnership with Premier Farnell enables us to better serve our growing customer base. Marrying the strengths of Maxim’s broad portfolio with Premier Farnell’s excellent design, supply chain, and logistical services further enhances our support of the design engineering community as engineers strive to bring their latest products to market as quickly and efficiently as possible,” said Ali Mortazavi, Vice President of Business Operations at Maxim. Mike Buffham, Global Director of Semiconductor and Passive Components, Premier Farnell, said: “We are excited by the opportunity this new investment in Maxim brings to us as it significantly builds upon our existing range of products stocked by element14. Maxim is one of the world’s leading suppliers of Analog technology and this strengthened partnership brings greater value that we are now able to bring to our customers. www. electricalmirror.in

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G-375, IIIrd Floor, Pocket II, Mayur Vihar Phase - I, Delhi - 110091

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Interview We are a progressive group and we always look forward for improving our market share with the Quality Products which we make

Apar has always believed strongly in the concept of collaborative growth and this vision has seen it emerge as India’s most respected and successful business organization. Apar has traced a route of growth that spans through many continents and diverse many cultures.

Over the years Apar has evolved into a USD 850 million diversified conglomerate. Apar is a dynamic example of growing downstream customer needs through the manufacture of niche Speciality Oils, Conductors and Power Cables.

Apar’s strength is Realiability: Build trustworthiness through consistency with our stakeholders, Innovating: Anticipating a leading change in our product and services, Adaptabilitdy: Change with the demand of a volatile & uncertain business environments, Leadership: Expect the best from us in Product, Quality, Capabilities and Services.

We are growing continuously and our % of growth in the last 5 years is in two digits. Just for your information we give you details of growth ie., 2010-11 – 36%, 2011-12 – 19%, 2012-13 – 29%, 2013-14 – 0% and in 2014-15 11%. This is only because of our Quality and making innovative products for our valued customers.

It is also brought to your notice that we had added and diversified in various present and new products and some of the milestones are given below:-

Vishvesh Bhatia Sr. General Manager/ Marketing- Apar Industries Ltd. Oil manufacturers in the World, Third Largest in the world for manufacture of Aluminium and Alloy Conductor.

Our Power Cable Division is also doing very well and is able to offer entire range of Cables ie., Power and Telecommunication. Apar has full range of cables like Rubber/Elastomeric, Optic Fibre, Specialty Cables, Under Water Cables, Cables for Renewable Energies plant like Solar and Wind Energy. We are proud to say that within a span of very short period Apar”s cable division was able to offer Innovative Cable Solutions. Apar’s export division for Cable is also doing very well exporting about 50% of the products produced.

payment due to which financial position of various companies in the Power sector are suffering. In addition to this discoms are not able to spend money for renovation of their projects which are very old.

Hence, Our future plans are to generation of achieve a turnover of Rs.1000 demand is not existing and Cr in next one or two year Power Industry in time and by 2020 we exIndia is suffering.

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pect to touch a turn over of Rs.2000 cr in Power and Telecom Cables.

Apar has diversified its activities 1. 1969 Special Oils Reinery at Mahul, Chembur and set up state of the art 2. 1998 Set up Rabale Oils Plant high Technology Electron Beam Irradiation facility 3. 2000 Set up Silvassa Oils Plant at Khatalwada, Gujrat for 4. 2002 Setup Silvassa Conductors Plant cross linking of for cross 5. 2007 Entered into Auto Lubes Segment Via Licence Agreement with eni S.P.A linking of insulation and Italy. innersheath polymers with 1.5 MeV 3.0 MeV 6. 2008 Acquired Uniflex Cables to diversify into cable manufacture. along with most modern 7. 2010 DSIR approved R&D Centre at Rabale. handling system for 8. 2012 Installed 2 E-Beam Accelerators Irradiation of various types of Electrical and 9. 2013 Conductors Plant set up at Athola Greenfield expansion to meet Automotive Cables, PE demand. sheets, Polymeric Tubes and Pipes, Heat Shrink Could you please give a brief description Products, Gems and Diamonds, Medical Products of the different business segments at APAR sterlisation and reprocessing of PTFE scrap etc.

Industries for our readers?

Apar is also one of the preferred suppliers for supply Apar Industries, founded by Late Shri Dharmsinh D. of Solar and Wind Mill Plants cables. Apar’s market Desai in 1958, commenced business for manufacture share is more than 50% for such types of cables. of Power Conductor for transmission of Power and According to you, which of the segment in 1969 diversified in the filed of Specialised Oils. has more growth potential in the coming 3 Gujrat Apar Polymers Ltd., was incorporated in 1989 or 4 years? and renamed as Apar Industries Ltd., in April, 1997.

In 2008 Apar acquired majority of Shares of Uniflex Since economy is growing and we hope that there Cables Ltd., and in April, 2010 Uniflex Cables Ltd., would be improvement in all segments. Government amalgamated with Apar Industries Ltd. Apar is one has given thrust on improvement in the Power Sector of the best established companies in India operating and have introduced new schemes also government in the diverse field of electrical and metallurgical has given thrust on Renewable Energy Plants ie., engineering.

Solar and Wind Energy. We expect there would be high growth for our Aluminium/Alloy Conductor Apar is evolved to be a US $ 850 million diverDivision and also in Cables particularly in Solar and sified company offering value added products Wind Energy. Fibre Optic Cables would also get and services in Power Transmission Conductors, good boost because government is improving the Petroleum Specialities and Power & Telecom Cables. broadband communication system.

We have strengthed the business of the customers with proactive product development, timely deliv- It is observed that pace of development in the power eries and superior product attributes by reinforcing sector generation is very slow because of longer innovations, competitive prices, premium quality and gestation period. Lot of disputes at the time of land living with our vision “Tomorrow”s progress today. acquisition and no proper coal linkages to the Power We believe in Realiability, Respect, Reputation and Plants. Hence, there are no new power generation as Repeat business across all manufacturing facilities. envisaged and power industry is suffering because of lack of requirement.

In 2007-2008 Apar established a strong foundation for Automotive Lubricants under a Licence What are the major challenges in the power Agreement with eni S.P.A, Italy for manufacturing industry in India? How do you overcome high-end automotive and specialty lubricants under with these challenges? the reputed “eni” brand in India.

Power Industry is doing well in India and condition We have our global presence in over 100 countries of industry can improve further provided discoms of the world. Apar is the fourth largest Transformer are able to make payment in time. They don’t make

Q

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You are serving the industry since 1958, share the successful journey of APAR Industries with our readers.

It is observed that pace of development in the power sector generation is very slow because of longer gestation period.

Lot of disputes at the time of land acquisition and no proper coal linkages to the Power Plants. Hence, there are no new power generation as envisaged and power industry is suffering because of lack of requirement.

It is observed that pace of development in the power sector generation is very slow because of longer gestation period. Lot of disputes at the time of land acquisition and no proper coal linkages to the Power Plants. Hence, there are no new power generation as envisaged and power industry is suffering because of lack of requirement.

In anticipation that huge power generation would improve year by year but it has been noticed that power generation is not improved as envisaged. In anticipation power industry improved their manufacturing capacity and hence they are suffering because of non utilization of their manufacturing capacity.

Another typical challenge is that there are no standardization of specification among the electricity boards/discoms due to which electrical industry is facing challenges to manufacture material against different specifications. Hence, cost of electrical goods produced with different construction is very high.

Foreign suppliers are very much active in the Power Industry due to which Indian Power industries are suffering badly because of heavy competition from the foreign suppliers.

On the Export front, Indian manufacturers are losing market share and the exports are dipping due to stiff competition. The Indian Power Industry is not able to compete effectively in the world market because of strong support of some of the countries like China, Middle East in terms of export subsidy, subsidy on raw materials, subsidy on social security and long term line of credit at lower rates of interest.

We are overcoming these challenges because at present we are not dependent on Power distribution companies/discoms to avoid problem in circulation of funds. We are also making lot of efforts in diversification so that new products are developed for the markets where competition is very less and good market price is also available. We have developed products for the Solar industry like Anti Rodent Solar Cables, Electron Beam Irradited Cables and also Flexible Aluminium conductor. We have also developed Wind Energy Cables upto 33 kv in Elastowww. electricalmirror.in

meric/Rubber construction for various international buyers. In addition to the above we have also introduced improvement of products quality and cost cutting so that we are able to compete in the global market ie., to keep a tap on the export market.

Government, has also considered various measure to improve the export market.

Q

What are the products you are going to showcase in Elecrama-2016? Is there

Fibre Cables/E Beam Irradiated Cables/Solar and Wind Energy Cables with latest developments.

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Share your plans for 2016 for your company.

We are a progressive group and we always look forward for improving our market share with the Quality Products which we make. It is not out of place to mention here that we have been getting premium in our products because we offer them niche product to our valued clients. We had

undertaken of expansion of Elastomeric/Rubber Cables and installation of 2 E Beam Accelerators. Our plans are to make further expansion of our Power Cable capacity, Installation of EHV Cables manufacturing units and going in for EPC business.

Our future plans are to achieve a turnover of Rs.1000 Cr in next one or two year time and by 2020 we expect to touch a turn over of Rs.2000 cr in Power and Telecom Cables.

any plan to unveil any new product in this event?

All products like ACSR / Alloy Conductors, Speciality Oils and Power Cables, Control Cables, Fibre Optic Cables, M e d i u m Voltage Covered Conductor, Speciality cables for Solar and Wind Energy Plants and also E Beam Irradiation products.

Please visit us at Stall # Hb38- Hall #3A and Stall # H5A6- Hall #5

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W h a t are the opportunities you are looking forward from this event?

ELECRAMA gives opportunity to the Indian Power Industry to showcase their products to Indian as well as the overseas buyers. This is a World Electricity Forum where many companies show case their products or developments which has taken place.

People from all the over world visit this show. The focus areas currently identified are in the areas of energy generation such as clean coal and renewable e n e r g y efficiency, smart grid and smart cities. We are one of the Conductor, Cable and Transformer Oil manufacturers are interested that we show case what sort of development or innovative solutions we have developed for the Power Industry and we may demonstrate them. We are looking new opportunities in the Medium Voltage Covered Conductor/Optic

www. electricalmirror.in

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TESTING AND MEASURING INSTRUMENT

“MONITORING POWER QUALITY & ENERGY EFFICIENCY”

IMPORTANCE OF MONITORING POWER QUALITY & ENERGY EFFICIENCY The Indian Power sector scenario remains gloomy, surrounded by the dark clouds. Although Power reforms started about a decade back, the achievements are only dismal. Financial health of most of the State Electricity Boards (SEBs) remains critical, mainly due to the uncontrolled use of low efficiency, Power wasting Equipment and Appliances, back breaking heavy subsidies for agricultural and some other sectors, and huge power thefts and pilferage resulting in heavy loss of revenue for the State Electricity Boards (SEBs) and other Utilities.

The major problems faced by the Power sector are due to increasing gap in th e Demand and Supply of Power, High Transmission and Distribution (T&D) losses as well as Power theft/Pilferage and wastage of expensive and limited Energy due to the use of Low Efficiency Equipment in various sectors. The prescription and implementation of Energy Conservation building codes has to be done in Consultation and co-operation

by Central & State Governments which will have the majors powers.

What is the Importance of Energy?

The importance of Energy. Energy is fundamental to the quality of our lives. Nowadays, we are totally dependent on an abundant and uninterrupted Supply of Energy for living and working. It is a key ingredient in all sectors of Modern Economies. Conserving Energy not only helps to Conserve Resources but also Translates into Financial Savings.

What is the definition of Energy Efficiency?

Energy efficiency is a way of managing and restraining the growth in Energy Consumption. Something is more Energy efficient if it delivers more services for the same Energy input, or the same services for less Energy input.

audit is very essential for reducing the T&D loss within optimum permissible limits, for which target are to be fixed and concerned efforts are to be mad to plug the leakages in the T & D system so that revenue collection of State Electricity Boards as well as Utilities increases which in turn will give a face-lift to them and improve their financial health.

Bureau of Energy Efficiency (BEE) also play key role in creation of professionally qualified energy managers and auditors with expertise in energy management, project management , financing and implementation of energy efficiency projects as well as policy analysis. It is a Law to force firms to make more profit and not an Act to control and monitor Energy Consumption of Industry.

Power Quality Power quality is often defined as the Electrical network’s or the Grid’s ability to supply a clean and stable Power Supply. In other words, Power Quality ideally creates a perfect Power Supply that is always available, has a Pure Noise-free Sinusoidal Wave Shape, and is always within Voltage and Frequency tolerances.

Power Quality is simply the interaction of Electrical Power with Electrical Equipment. If Electrical Equipment operates correctly and reliably without being damaged or stressed, we would say that the Electrical Power is of good quality.

For quality performance of various power system devices it is necessary to understand the problems due to Harmonics deeply and take further remedial measures for improvement and better performance.

Under the BEE’s PAT Scheme (Perform, Achieves & Trade) for Eight following Industrial Sectors, it is mandated to compulsorily improve their Energy Efficiency by adopting all the available measures including replacement of their old Equipments with New and Energy Efficient Equipments: Aluminum Cement

Chlor – Alkali

Fertilisers

Iron & Steel

Pulp & Paper

Textile and Thermal Power Plants

All the Assets, Liabilities and Employees of the existing Energy management center was suppose to be transferred to this bureau. The central government through its Ministry of Power, the Bureau of Energy Efficiency &

Harmonics, voltage flicker, voltage regulation, voltage sag, voltage swell and transients usually characterize the quality of electric power.

With Energy Efficiency, you don’t have to sacrifice comfort to Save Energy. Energy Conservation involves a change in behavior to save Energy (Turning off the lights, Powering down Computers and Electronic Equipment at night, Lowering the Thermostat in winter and Raising it in Summer, Implementing Auto Power On System for Centralizing Air conditioner, Cooler etc to minimize the wastage of energy).

The presence of harmonics distorts the waveform shape of voltage and current. increases the current level and changes power factor of supply, which In turn creates so many disturbances.

Sources or Causes of Harmonics

Energy Conservation:

the State Governments will have a major role to achieve the desire objectives. Bureau of Energy Efficiency (BEE) has estimated a potential of more then 25% savings through energy conservation.

With the move towards deregulation within the Power utility industry, customers are demanding superior Power quality and reliability of Supply. Many utilities have responded to the needs of their customers by establishing Power Quality Divisions within their marketing departments.

As can be seen from the above, this is a stupendous work and needs full co-operation from manufacturers and the users of the Energy, as well as the Central and the State Governments.

The Energy Conservation Bill-2001 was passed by the Parliament in August-2001 and was expected to clear the way for to check Wastage Energy. This Bill was supposed to control huge wastage of Power. The Energy Conservation Bill 2001 prepared by group of expert committees discussed and debated at various forums, was passed by the Indian Parliament in august-2001.This a Bureau called the Bureau of Energy Efficiency (BEE) was established and managed through Governing council.

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A growing power quality concern is harmonics distortion that is caused by the non - linearity of customer loads.

The power quality may defined as any problem manifested in Voltage, Current or Frequency deviations that results in failure or misoperation of customer sites or equipments.

Harmonics is one of the major factors due to which none of these conditions are fulfilled in practice.

It can thus be concluded that energy accounting and

More use of solid state power converters for industrial furnaces for mini steel and non-ferrous metal plants, use of thryistors for locomotives, extensive use of single phase electronic loads in domestic sectors are causes of harmonic generation.

HARMONICS – A Power Quality Problem

What is the difference between Energy Conservation and Energy Efficiency?

However the implementation of Energy Conservation Bill-2001 has to be done through well qualified and experienced Energy Managers with the designated consumers and the Energy Auditors to check & certify that every such consumer complies with the provisions of this bill, thereby conserving the Energy, which of course will benefit the consumers themselves reducing their own Energy Bills and such savings increasing their profitability.

level. Related to the supply system converters and traction are the major causes of generation of harmonics.

MECO “POWER & HARMONICS ANALYZER – Model 5850” Analyzer which is a state of art versatile instrument using micro controller technology and having various functions that would be ideal for Energy Auditor, Engineer, Inspector for carrying out Energy Audit, Surveys, Periodic visit for Monitoring & checking at Industrial and Consumers end.

Rapid use of energy conservation devices in both domestic sectors and industrial sectors such as electronics chokes for tube lights, electronics energy controllers for the motors and electronic fan regulators etc. also inject harmonics substantially.

“ Haren Shah is Commerce Graduated from Mumbai University. He is associated with M/s. Meco Instruments Pvt. Ltd. Navi Mumbai more than 20 Years”

Large use of the shunt capacitors to improve power factor and stability has significant influence on harmonic www. electricalmirror.in

HALL No.: 4C, STALL No.: H4V75

www. electricalmirror.in

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Would you like freedom from following in your transformers?

Oil filtration GEW Trafotech transformers have in- built oil purification system, hence do not require oil filter through filter machine. Transformers operate dry, not wet. Life of transformer= Life of insulation

Maintenance on Breather

Basically silica-gel breathers are not required in GEW Trafotech transformers. The transformers are equipped with patented “Sealed-breathing system”. Moisture entry is not permitted, resulting in life extension of T/f and thereby huge savings

Tightening of windings

To make up shrinkage of windings (required after a decade of operation), an auto-tightening system is provided inside the transformer. This prevents outage period

Installing fire extinguisher system

We can provide fire-safe transformers. Fire protection systems can-not prevent fire occurrence and work only after fire takes place.

We can convert normal T/f s to Fire-safe transformers and extend their life

More services we offer Inject life in your transformers….!!

Up-gradation Up-grade KVA Capacity of existing transformers by 15%

Up-gradation Up-grade any OLTC by allowing more than double the number of operations without an overhaul

Up-gradation We are first in the world to provide "Sealed breathing system" of OLTCs of any make

Conversion Convert existing transformers to filter-free transformers by installation of SBS and oil purifier on transformer, without altering the existing design.

Silica-gel breather for distribution transformers

In place of breather, sealed flexi-breather is provided which expands and contracts as required, exactly like lungs.Isolation from atmospheric moisture is 100%

SFRA First time in the world, we have introduced winding dislocation monitor system which gives indication of winding dislocation on control panel of energized transformers. SFRA NOT REQUIRED

Breakdowns

Maintenance Repair/re-conditioning/condition monitoring of transformers 500 KVA to 500 MVA

Making work easy No wiring needs to be perfomed by client between OLTC and RTCC panel

We prevent and minimize damage, in the event of OCTC failure, by placing Off circuit tap switch outside the main transformer tank

GEW Trafotech Pvt. Ltd. C 35-36, UPSIDC, Naini, Allahabad United Trafotech Pvt. Ltd. A 49, Nirman Vihar, Delhi 110092

Contact person Anurag Malhotra +91-98100 16323 Mayank Seth +91-96284 77111 Abhas Mittal +91-95549 61001

Email: trafowork@trafotech.net, sales@gewtrafotech.com

www.gewtrafotech.com|| www.trafotech.net

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