ELECTRICAL SECTION

OF

PH – I (4 x 15 MW) POWER HOUSE

LAKWA THERMAL POWER STATION (LTPS)

UNDER

ASSAM POWER GENERATION CORPORATION LIMITED (APGCL), ASSAM

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LIST OF CONTENTS

1. About PH - I Power House2. AC Generator3. Excitation system of Generator4. Alarm and protection features of Generator5. AC supply system6. DC supply system7. Specification of different AC & DC auxiliaries8. Single line diagram of LTPS

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1. About PH - I Power House

Lakwa Thermal Power Station (LTPS) is one of the leading power generating station of Assam under Assam Power Generation Corporation Limited (APGCL). This power station is located at Maibella, Sivasagar, Assam. Total installed capacity of LTPS is 120 MW. LTPS is a natural gas based thermal power station where natural gas received from GAIL, Lakwa and AGCL, Duliagan. LTPS has two power houses namely PH – I power house and PH-II power house. In PH – I power house, there are four (4) Gas Turbines of 15 MW capacity each and in PH – II power house there are three (3) Gas Turbines of 20 MW capacity each. The generated voltage of LTPS is 11 KV and stepped it up to 132 KV for high voltage transmission. The generated power is transmitted to different transmission sub-stations.

In PH – I power house Gas Turbine (GT) no. 1, 2 & 3 are Westing House, Canada make and GT no. 4 is Mitsubishi, Japan make.

2. AC Generator

The AC generator generated AC power by converting mechanical energy into electrical energy.

RatingThe Westing House Canada Limited make are rated as

Type & Frame: HG 75 ½Salient pole, Air cooled

Rating: 15,200 KW (Base) 16,700 KW (Peak)……… 3 Phase17,882 KVA (Base) 19,647 KVA (Peak)……. 50 Cycles11,500 Volts……………………………………. 750 RPM898 Amps (Base), 987 Amps (Peak)……….. 125 A-C Exciter Field Volts85% Power Factor…………………………….. 3.5 (Base), 3.7 (Peak) A-C

Exciter Field Amps.Class of insulation – Class FDegree of Enclosure – EnclosedMethod of Cooling – Duct ventilatedMeans of Excitation – Permanent Magnet Generator supplies field excitation

to brushless AC exciter.Prime Mover – Westinghouse Gas Turbine

AC Exciter

Type & Frame: EBX5ABrushless, direct connected

Rating: 111 KVA119 Volts539 Amps 62.5 Hertz90% Power Factor

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3 Phase, 750 RPMPermanent Magnet Generator (PMG)

3 KVA, 208 V, 14.5 A, 210 Cycles, Phase-1, RPM 900.

General Arrangement:

The a-c generator is coupled to the turbine gear by a forged flange coupling. The shaft is supported at the opposite end of the generator by a split sleeve pedestal bearing. The stator frame is mounted on sole plates. The a-c brushless exciter is overhang on the generator shaft extension, outboard of the pedestal bearing and permanent magnet two bearing generator is flexibly coupled to the generator shaft.

Frame:

The frame is formed of welded, hot-rolled steel members. Removal covers on the stator frame adjacent to the feet and one the side furnishes access to jackscrews, foundation bolts, temperature detector terminal board, space heater terminal board, and lifting lugs on the inside of the frame. Heavy steel feet are welded to the lower portion of the frame. These feets are machined parallel to the shaft and are drilled for foundation bolts, dowel and jackscrew. A bottom cover provides alternate access to the space heater.

The core laminations are stamped from special silicon steel. They are stacked on transverse bolts and are clamped by steel end rings bolted together. Ventilating spaces are provided by fingerplate spacers permitting air to circulate through the core. Terminals of the stator winding are brought out at the bottom of the frame.

End Covers:

Air shields are end covers are sectionalized are bolted to the frame at each end. The covers enclose and protect the stator end winding and direct the ventilating air from the side at each end into the generator. The inner endbell has removed front and rear for checking the air gap between stator and rotor. Flanges on outer endbells provides mean for connecting to customer ducts. The outer endbell at the coupling end has a removable weather seal to the gear shaft.

Bearings:

The shaft is supported by a split sleeve pedestal bearing at the a-c exciter end. Lubrication is provided by the forced-feed system of the prime mover. A fixed orifice at the bearing inlet regulates the oil flow through the bearing to six gallons per minutes at a pressure 15 pounds-per-square-inch.

In addition to oil throwers machined on the shaft, front and rear oil seals are provided to prevent leakage of oil from the bearing. The seals are of the labyrinth type which are fastened to the bearing pedestal and cap. The small clearance the shaft and the inner periphery of the seals prevents leakage of oil along the shaft away from the bearing. The bearing is insulated and any connection to the pedestal must be insulated to prevent flow of possible shaft currents.

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Stator Core:

The core of the machine is built up of circular segmental laminations of silicon steel stacked on transverse studs. Each circular lamination consists of nine segments. Ventilating spaces are formed between the frame rings and the ends of the core by finger-plate spacers, and between the packages of punching vent-plate spacers at positions along the length of the core. This arrangement furnishes a mean for dissipating heat from the core by permitting cooling air to enter the inner portion of the core. The laminations are insulated from one another with a surface coating of Alka-phos. Finger-plates at each end of the core prevent loosening of the teeth. The stator punching have 84 slots each having a finished size, after stacking, of 0.845 inch wide by 4.790 inches deep.

Terminals:

The a-c generator stator leads are brought out of the bottom of the a-c generator facing the a-c exciter end. The 3/8 “ x 3” strap leads three for line and three for neutral leads are drilled and Burndy Q2A40-4N terminals for two 750 MCM cables per lead are supplied.

Armature (Stator) Winding:

Coil groupings: 3 and 4 coils per group, 1 group per pole-per phase – 3 groups per pole – 24 groups total 84 coils.

Throw of coils: Slots 1 to 10 – 8 poles – 3 phase – 2 parallel – starThe armature coil is of the diamond type and consists of 5 conductors consisting of 2

layers brick type construction with each layer made up of 0.072 inches by 0.289 inches un-insulated and 0.087 inches by 0.303 inches double glass insulated in parallel with a stand of 0.087 inches by 0.204 inches un-insulated.

Mecarta wedges are used to hold the coils in place in the slots. The coils are roped to a braced insulated steel ring on each end of the winding to prevent distortion in case of short-circuit. Arch bound spacers are roped between the coil end sections.

Shaft and Spider:

The shaft for the a-c generator is machined from a steel forging and is provided with an integral flange on the rear end for coupling to the speed reducing gear. The spider which carries the field poles is built up of steel laminations riveted together, the assembly being shrunk on and keyed to the shaft. The spider laminations are punched with dovetail slots for mounting the field poles.

Field (Rotor) Poles:

The eight poles are constructed of laminated steel punching which are securely bound together by through studs. Each field pole is fastened to the spider by a dovetail, which is held in place by two sets of two tapered keys.

Copper damper bars extend axially just beneath the face of each pole. These bars are brazed at each end of the pole to an end ring. These end rings are all connected between poles.

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Blowers:

A radial type blower assembly is mounted on each end of the rotor assembly. These blowers are suitable for the given rotation.

Generator Ventilation:

Ventilating air enters through the intake ducts to front and rear generator outer endbells flows into the inner endbell where rotor mounted directional blowers increase the flow and pressure. The air shield directs the air through the interpolar spaces and air gap and through the stator ventilating ducts into the region behind where it is directed upward for discharge out the top.

Field (Rotor) Winding:

Each field coil consists of a pre-formed section of 69 turns of 0.085 x 2.50 inch insulated strap copper. As the coil is wound, each layer is brushed with synthetic resin. The coil is pressed in the turn directions, the inside of the coils is blocked and clamps are applied during the pressing operations. The coil is cured and pressed to stresses greater than encountered in operation.

After the coil is removed from the mould, the coil is insulated from the pole with u-shaped pieces of reinforced mica placed inside the coil and turned out over the top and bottom edges of the coil. The coil is assembled on the pole with Micarta washers; after assembly it is treated in moisture and oil-resisting varnish. Each coil is secured in the position on the pole by the upper coil support, wedge washers and spring support. Interpolar braces support the coil sides. The upper coil support is made from aluminium bar and is secured to the pole head. The wedge washer is made of mica and is under the Micarta bottom washer. The springs are made of steel and fit between the spider bearing surface of the field coil and press tightly against the bottom washer.

Space heaters:

Eighteen 500 watt, 240 volt space heaters are located in the bottom of the machine frame. These heaters are connected in 3 parallels of 2 in series for delta 380 volt, three phase operation.

AC Exciter

Stator:

The stator is fabricated from rolled steel plate. The single segment pole laminations are stacked on building bars between two steel frame rings. The laminations are tightly clamped in a jig and spacers are welded to the frame rings. Steel plate feet extend parallel to the shaft and assure rigid attachment of the exciter to the rails. Each frame foot is drilled for hold down bolts and dowels.

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Endbells:

Rolled steel end bell sections are bolted to the ends of the exciter frame to protect the ends of the windings and direct rhe ventilating air to the rotor.

Field (Stator) Winding: Field coils are mould wound, class B insulated with 540 turns copper wires. Coils are

securely held in place on the pole pieces by bolted coil supports. The field leads are brought out to a conduit box located on the side of the exciter.

Exciter Ventilation:

The a-c exciter has a dripproof enclosure. Ambient room air enters top rear enclosure through filters and discharges at bottom front of exciter.

Diode Wheel:

The semi-conductors are located on insulated heat sinks mounted on the bore of the connector support rings. Six forward and six reverse diodes are connected to form a three phase rectifier bridge. The a-c output from the exciter is rectified in the diode bridge circuit and applied to the a-c generator field through shaft mounted conductors.

Rotor:

The exciter armature is of steel construction consisting of single segment laminations, spider, hub and coil supports. The core assembly of the armature laminations, vents and end fingers are clamped between endplates accurately located on machined spider fits and keyed for permanent aligment.

AC exciter Space heaters:

Two 250 watt 240 volt space heaters are located at the bottom of the field yoke. These heaters are connected in star for 380 volt, 3 phase, 625 watt operation.

The Mitsubishi, Japan make generator is rated as Rating: 16,906KVA, 14370 KW

11,500 Volts849 Amps 50 Hertz

85% Power Factor3 Phase3000 RPMType MB250 Exc. Volts, 320 Exc. Amps.160 KW 250 V DC Brushless Excitation

AC Exciter

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Rating: 178 KVA, 160 KW200 Volts (AC)513 Amps (AC) 200 Hertz8 Pole98% Power Factor3 Phase3000 RPMOverhang type, Insulation class – F110 Exc. Volts, 11.7 Exc. Amps.

Permanent Magnet Generator (PMG)

2.5 KVA, 100 V, 0.95 power factor, 300 Hertz, 3 Phase, 3000 RPM, 12 Pole, Insulation class F.

3. Excitation system of Generator

TYPE PRX – 5 POWERTREX VOLTAGE REGULATOR AND BRUSHLESS EXCITATION SYSTEM FOR WESTINGHOUSE MAKE GENERATOR

PURPOSE AND APPLICATION

The purpose of the excitation switchgear is to connect, rectify and control excitation to an a.c. brushless exciter from a permanent magnet generator with an a-c output. Connection is accomplished through an a.c. field supply breaker: rectification is accomplished by a thyristors power unit; and automatic control is accomplished by a Powertrex voltage regulator.

Control of the brushless exciter field current governs the output of the a-c exciter, which through the shaft mounted rotating rectifiers furnishes excitation to the field of the main generator. The excitation may be controlled either manually by a “base adjuster” or automatically by the voltage regulator in response to the terminal quantities of voltage and current of the main generator.

DESCRIPTION

The excitation switchgear is a standard low voltage metal enclosed unit. Powertrex components are panel mounted on a frame which can be applied with a standard cubicle or mounted in other available space. All components, power unit, field breaker,, etc., are easily accessible from the front of the cubicle.

OPERATON

It is assumed that the unit is at rated speed for these operations. With the regulator out of service, the signal mixing module output is disconnected by the relay contacts 90X, and only the base adjuster is controlling the firing circuit module, which in turn controls the thyristor inverter power amplifier. The base adjuster output is of sufficient range to drive the power unit from cutoff to ceiling output. With the regulator in service, the voltage regulator module is connected through the signal mixing module and relay contacts to the

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firing circuit module. The base adjuster and voltage regulator signals are summed at the firing circuit module input, but the voltage regulator signal has the ability to override any setting of the base adjuster potentiometer. Figure 1 is a graphical representation of the inputs and outputs of the voltage regulator, the base adjuster, thyristor power unit, the brushless a-c exciter and the a-c generator.

COMPONENT DESCRIPTION

The Phase Shifter (Current to voltage transducer panel) transform a phase B current signal into two phased voltage signals for acceptance by the reactive compensator module and the minimum excitation limiter module.

The reactive compensator module accepts the current derived voltage signals from the phase shifter and adds the compensation signals to the voltage regulator sensing circuit. A single control provides a wide range of adjustment to provide sufficient voltage droop for paralleling of machines.

The minimum excitation limiter module monitors the three phase generator voltage and relative phasing of the generator current derived voltage signal (produced by the phase shifter) to generate a circular curve. This curve is similar to and follows the same laws as the static stability limit of the synchronous machines.

The power supply module connected in to supply all the needs required by the logic circuitry.

The voltage regulator module monitors the three phase generator output voltage. Average of the three phase sensed voltage is compared to a stable reference voltage within the module. The resultant error signal is fed into the signal mixing module for firing circuit control.

The motor operated voltage adjuster provides for remote control of the voltage regulator level.

The signal mixing module chooses the most positive signal produced by either the voltage regulator or the minimum excitation limiter module. The resultant signal is summed with the damping signal to produce the two firing circuit control signals.

A-C Excite

r

PMG A-C GEN

AUTOMATIC VOLTAGE

REGULATOR

FIELD

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The signal mixing module output signal is monitored by a null-transfer meter. Before transfer to automatic operation, the regulator voltage adjuster is adjusted to null the meter.

Stabilization of the regulator system is effected by the damping module and its voltage transducer module. The damping signal is derived from the output current of the exciter field for coupling to the signal mixing module.

The motor operated base adjuster provides for remote control of base level of excitation. The M.O. base adjuster signal is fed into the firing circuit card to obtain a fixed value of field current.

The signal mixing module output is added to the base adjuster signal at the firing circuit module input. This firing circuit controls the PRX-5 single phase thyristor power amplifier. The power amplifier is a single phase full wave inverting type and is rated at 16 amps. d. c. at 175 V. A 10 ohm limiting resistor has been added to the exciter field current to limit the field current to 7 amps d.c.

Automatic Voltage Regulator System Type VRG-PMH-VI

This equipment automatically controls the field system of generator so that the output voltage of the generator will be at the set point. It has such attachments as

a) Amplifier circuit L-AVR01 card,b) Phase control and thyristor firing circuit L-GPG02 card,c) Digital setter L-DST01 card,d) Minimum excitation limiter (MEL) L-LIM01 card,e) Over excitation limiter (OEL) circuit L-LIM01 card,f) Auto follower circuit L-DST01 card,g) DC power source circuit,h) Thyristor main circuit,i) Cross current compensator

4. Alarm and protection features of Generator

Equipment is provided to protect the turbine-generator unit in the event of abnormal operation while starting or running. Some of its protective devices merely annunciate and sound an audible alarm to call the operator’s attention to this abnormal condition. Other devices, in addition to providing the visual and audible alarm signal, will also cause complete shutdown.

One annunciator is provided on the turbine control panel for turbine alarms and for generator alarms.

The following protective devices operate through the annunciator for protection of generator.

Voltage Regulator Off

If the voltage regulator trips under automatic control, or is switched off under manual control, the annunciator will give audible and visible warning.

Generator Differential

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A differential relay, device 87G, is supplied for protecting the generator. In event of an internal fault, this relay will operate to energize the lockout relay 86G. Contacts on this device will then immediately trip the generator line and field breaker. The turbine will continue to operate at no load until shutdown by the operator.

Generator Field Loss, Generator Ground

Loss of generator field will operate device 40 and cause lockout relay 86G to operate and to trip generator and field breaker.

A ground on the generator phases will detect by the CO-8 ground current relay (device 64G) connected across the secondary winding of the generator neutral ground device. Operation of this device 64G will energize the lockout relay 86G. As a result, the generator and field breaker will trip.

Generator Negative Sequence, Reverse Power and Overcurrent

Negative sequence current in the generator will operate device 46 and cause lockout relay 86G to operate and to trip generator and field breaker.

Reversal of power flow from the line into the generator is detected by the type CRN-1 (anti-motoring) reverse power relay, device 67. If this condition ever happens, the reverse power relay will close its contacts and energize lockout relay 86Gto cause a partial shut down by tripping breakers 52 and 41.

Voltage restrained overcurrent relays are supplied to provide overcurrent protection for the generator. In the event of high current, which also causes reduction in the system voltage to the COV-8 overcurrent relays, devices 51V will operate and energize lockout relay 86G. This will result in immediate tripping of the generator line and field breaker to clear the overload. The turbine will continue in operation, running at normal speed.

Generator Over temperature

Excessive stator temperature will operate device 49 and cause lockout relay 86G to operate and trip generator breaker and field contactor.

GENERATOR CONTROL SECTIONEach generator control section includes control, instrumentation and relay

protection for each generator and associated breaker. Relay protection includes the following:

(a)COV-8 voltage controlled overcurrent relays,(b) COQ generator negative sequence relay,(c) CRN-1 anti-motoring relay,(d) CWD reverse power relay(e) DT3 generator stator temperature detector relay,(f) CD-8 ground current relay,(g) SA-1 generator differential protective relays,(h) KLF generator field loss relay,(i) CV-7 undervoltage relay,(j) CV-8-D 11 KV Bus E/F protection relay,(k) D-5-D generator rotor E/F protective relay,

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(l) TF1B-D generator low frequency trip relay,(m) TF1B-D GT low frequency trip relay.

5. AC supply system

CT-11200/5A

(UNDER GEN)

GEN DIFFERTIAL PROTECTION

RELAY

11.5KV GEN

50 HZ

PT-112000/120 V

TO EXCITATION CONTROL

PT-212000/120 V

TO METERING, DISPLAY,

PROTECTION & SYNC.

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15 KVA NEUTRAL GROUNDING

TRANSFORMER

CT-21200/5A

TO UAT

TO METERING AND

PROTECTION

TO GEN TRANSFORMER THROUGH GEN CIRCUIT BREAKER

CT-31200/5 A

(UNDER GEN)

TO GENERATOR GROUND FAULT RELAY

TO CUSTOMERS’ OVERALL DIFFERENTIAL

CIRCUIT

CT-41200/5A

TO EXCITATION CONTROL

GENERATOR CIRCUIT BREAKER

CT-51200/5A

PT-312000/120V

GEN DIFFERTIAL PROTECTION

SYNCHRONISATION

Fig. Supply to GTMCC for different GT auxiliaries.

FROM 11KV GENERATOR

BUS

150 KVA, 11500/380 V

UAT

TO 380 V, 3 Φ, 50 HZ, GTMCC

BUS

ROBONIC AUTOMATIC TRANSFER

SWITCH

FROM 380 V, 3 Φ, 50 HZ, RESERVE

SYPPLY BUS

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6. DC supply system

The DC power supply is capable of delivering continuous power at the specified load. This system consists of the Battery Charger and Battery. The battery charger is an AC to DC rectifier and is capable of supplying the full load current requirements of the system and a recharge current for the battery. The battery is capable of supplying the full DC load current requirements of the system during AC power failure.

In the event of a failure of the AC input power to the charger, the system is powered from the battery to provide uninterrupted power to the load. When the AC input power is restored, the battery charger will supply to the load and recharge the battery.

Unit #1, 2 & 3 DC System Block Diagram:

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415 V, 3 Φ, AC SUPPLY

BATTERY CHARGER

BATTERY BANK CONSISTING OF 60

CELLS OF 250 AH, 2 V PER CELL

120 V DC

DCMCC

TURNING GEAR

MOTOR

DC LUBE OIL PUMP

CLUTCH AIR COMPRESSOR

CONTROL CIRCUITS

HV SWITCHGEAR TG CONTROL

PANEL

Field Breaker Control

InverterVibration Monitor

Unit #4 DC System Block Diagram:

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415 V, 3 Φ, AC SUPPLY

BATTERY CHARGER

BATTERY BANK CONSISTING OF 60

CELLS OF 290 AH, 2 V PER CELL

120 V DC

TURNING GEAR

MOTOR

DC LUBE OIL PUMP

CLUTCH AIR COMPRESSOR

ADLL. MCC

GTG CONTROL

BOARD(GAS

TURBINE CIRCUIT)

3.3 KV G.C. STARTER CONTROL CIRCUIT

11 KV SWITCHGEAR

DIESEL ENGINE PANEL

EMERGENCY LIGHTING

BATTERY INVERTER

FIRE DETECTOR

GTG CONTROL

BOARD(EXCITATION

CIRCUIT)

GTG CONTROL

BOARD(MEGAC-V CIRCUIT)

GTG CONTROL

BOARD(PROTECTIV

E RELAY CIRCUIT)

DCMCC

DC MCC

100 V AC

GTG CONTROL BOARD

(INSTRUMENTATION CIRCUIT)

GTG CONTROL

BOARD(MEGAC-V CIRCUIT)

OPS-1(OPS1 + ENG

TOOL)

OPS-2(OPS2)

(FOR ENGINEER EWS OR SPARE)

7. Specification of different AC & DC auxiliaries

Gas Turbines # 1, 2 & 3

(a) Lube Oil Cooler Fan Motors:

15 KW/20 HP, 440/400 V, 29.5 A, 3 PHASE, 1460 RPM.

(b) Primary Auxiliary Lube Oil Pump Motor:

30 HP, 415 V, 44 A, 2935 RPM, Westinghouse make.

© Instrument Air Compressor Motor:

KW, 10 HP, 415 V AC, 13.6 A, 3 PHASE, 1455 RPM, CG make Induction motor

(d) Turning Gear Motor;

5 HP, 125 V DC, 35 A, 1750 RPM Westinghouse make DC Motor

(e) DC Emergency Lube Oil Pump Motor:

3 HP, 125 V DC, 21 A, 1750 RPM, Shunt winding, Westinghouse make(f) Clutch Air Compressor Motor:

1.5 HP, 125 V DC, 11.4 A, 1750 RPM, Shunt winding, Westinghouse make

Gas Turbine # 4

(a) Lube Oil Cooler Fan Motors:

2.2 KW, 6 Pole, 460 V, 50 HZ, 4.1/4.4 A, 3 PHASE, 960/1120 RPM.

(b) Primary Auxiliary Lube Oil Pump Motor:

45 KW, 2 Pole, 415 V, 75 A, 2960 RPM, 50 Hz, 3 phase Induction motor.

© Instrument Air Compressor Motor:

7.5KW, 4 Pole, 415 V AC, 14.8 A, 3 PHASE, 1450 RPM, Induction motor

(d) Turning Gear Motor;

3.7 KW, 125 V DC, 40 A, 1500 RPM Shunt winding Super line DC Motor

(e) DC Emergency Lube Oil Pump Motor:

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4.2 KW, 125 V DC, 44 A, 1800 RPM, Shunt winding, Super line DC Motor

(f) Clutch Air Compressor Motor:

22 KW, 4 Pole, 125 V DC, 24 A, 1500 RPM, Shunt winding, Super line DC Motor

Generator transformer # 1, 2 & 3:

Make: Crompton GreavesLimited, BombayMVA: 22.5KV (No load): HV 138 LV 11Frequency: 50 HzVector symbol: Yd11Amperes: HV 94.135 LV 1180.98Phases: HV 3 LV 3Impedance Voltage at 750 C on 22.5 MVA base: 9.87%Type of Cooling: ON/OB on rating 11.25 MVAYear of Manufacturing: 1979.

Generator transformer # 4:

Make: Bharat Bijlee Transformer, BombayKVA: 15000/22500KV (No load): HV 138 LV 11Frequency: 50 HzVector symbol: Yd11Amperes: HV 62.8/94.1 LV 788.23/1182.3Phases: HV 3 LV 3Impedance Voltage at 750 C on 22.5 MVA base: 9.87%Type of Cooling: ON/OB on rating 11.25 MVAYear of Manufacturing: 1979.

Unit auxiliary transformer # 1, 2 & 3:

Make: EMCO transformer LimitedKVA: 150Volts (No load): HV 11000 LV 415Frequency: 50 HzVector symbol: Dy1Amperes: HV 7.875 LV 208.7Phases: HV 3 LV 3Impedance Voltage: 3.987%Type of Cooling: AN .Unit auxiliary transformer # 4:

Make: TECHNOVELKVA: 315Volts (No load): HV 11000 LV 405Frequency: 50 HzVector symbol: Dy1

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Amperes: HV 16.53 LV 454.66Phases: HV 3 LV 3Impedance Voltage: 4.4%Type of Cooling: ON/AN

Reserve transformers (R5 & R6):

Make: Eastern transformer & Equipment LimitedKVA: 500Volts (No load): HV 3300 LV 415Frequency: 50 HzVector symbol: Dy1Amperes: HV 87.4 LV 696Phases: HV 3 LV 3Impedance Voltage : 4.72%Type of Cooling: ON

Gas Compressor # 1 & 2 driving Motor:

Westinghouse make, HS type, 3 Phase, 50 Hz, H688K Frame, 700 HP, 3300 V, 107 A, 985 RPM, Insulation class- B.

Gas Compressor # 3 driving Motor:

BHEL make, 3 Phase, 50 Hz, 525 KW, 3300 V, 124 A, 988 RPM, , Insulation class- F, Induction motor.

Gas Compressor # 4 & 5 driving Motor:

Mitsubishi make, F4KI-WX type, 3 Phase, 6 Pole, 50 Hz, 500L Frame, 825 KW, 3300 V, 175 A, 985 RPM.

Gas Compressor # 1 & 2 Water Pump Motor:

Westinghouse make, 3 Phase, 50 Hz, 5 HP, 415 V, 7 A, 2890 RPM.

Gas Compressor # 3 Water Pump Motor:

3 Phase, 50 Hz, 5.5 KW, 415 V, 9.8 A, 2925 RPM, 132S frame.

Gas Compressor # 4 & 5 Water Pump Motor:

3 Phases, 50 Hz, 1.2 KW, 2 Pole, 415 V.

Gas Compressor # 1, 2 & 3 Pre Lube Oil Pump Motor:

3 Phase, 50 Hz, 1 HP, 415 V, 1.7 A, 1430 RPM, Westinghouse make.

Gas Compressor # 4 & 5 Pre Lube Oil Pump Motor:

3 Phase, 50 Hz, 1.2 KW, 4 Pole, 415 V.

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Gas Compressor # 1, 2 & 3 Heat Exchanger Motor:

15 KW/ 20 HP, 415 V, 27.5 A, 1450 RPM.

Gas Compressor # 4 & 5 Heat Exchanger Motors:

7.5 KW, 4 Pole, 415 V, 14 A.

Instrument Air Compressor Motors for gas Compressors:

10 HP, 415 V, 14.1 A, 1465 RPM. Westinghouse make.

8. Single line diagram of LTPS:

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