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Matrishri Usha Jayaswal Mega Power Project DCPL-K9A052x270MW,CHANDWA TPS

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Ref.: K9A05/DCH-4/E/BHEL Annexure-A -Dated 26.04.2011Comments/Observation:- Electrical

Ref.: GENERATOR RELAY PANEL

Drawings:

1) Dwg. No. PE-DG-344-510-E001,Rev0 10 Shts: Single Line Diagram for Generator,GT& UAT Circui t

Metering & Protection.

2) Dwg. No. PE-DG-344-510-E002,Rev0 34Shts: Logic Diagram for Generator,GT& UAT Circui t

Protection. & Annunciation.

3) Dwg. No. PE-DG-344-510-E003,Rev0 7Shts: CT & VT Calculation for Generator,GT& UAT Circui t

Metering & Protection.

Action-4

A. Please note the following forCalculation-

a) BHEL to check & revise the fol lowing parameter as per BHEL equipment Data Sheet.

1) Xd of Generator =16.8% ( instead of 15.5% ).

2) %Z of GT = 15.1% 10% on 340 MVA base instead of 14.5%.

3) %Z of UAT = 10% 10% on 20 MVA base instead of 10% only.

b) BHEL to consider Conductor resis tance value at 75C.

c) BHEL to provide CT parameter as per JPL

1) VkofCT-11000V at Rct= 2 ohms @75 C &Ie 150mA at Vk/4 .

2) Burden ofCT-2 =75VA.

3) VkofCT- 3 & CT- 4600V at Rct= 2 ohms @75 C.

4) VkofCT- 5 & CT- 6600V at Rct= 2 ohms @75 C.

5) Burden ofCT-7 =75VA.

6) Burden ofCT-8 =75VA.

7) Details o fCT-9 =600-400/5A, CL-0.2, 50VA.

8) VkofCT-13A, 13B 300V at Rct= 2 ohms @75 C &Ie 30mA at Vk/4 .

9) VkofCT-15A, 15B 1000V at Rct= 2 ohms @75 C &Ie 150mA at Vk/4 .

10).Burden of VT-3 =75VA and IVT-1=30VA. Accuracy Class of IVT-2 =1.0

11). Provide another IVT, before 64GIT.

d) BHEL to provide CT parameter as per their equipment viz. GT & UAT

1) VkofCT-10, Core-1500V at Rct= 5 ohms @75 C &CT ratio = 500/1-1A .

2) Burden ofCT-10, Core-2 =30VA &CT ratio = 500/1-1A .

3) VkofCT-11500V at Rct= 5 ohms @75 C &CT ratio = 500/1-1A.

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Matrishri Usha Jayaswal Mega Power Project DCPL-K9A052x270MW,CHANDWA TPS

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4) CT ratio = 200/1A ofCT-16A, 16B, Core-2(instead of Core-1) Standby Earth fault.

5) CT ratio = 300/1A ,ofCT-16A, 16B, Core-1(instead of Core-2) Restricted Earth fault.

6) CT ratio = 300/1A, Ith=2000A ofCT-17A, 17B (delete Core-1) Restricted Earth fault. Vkof

CT-17A, 17B> 100 *(RCT + 5) at Rct= 1 ohms @75 C.

e) Input to BHEL to provide CT parameter ofAREVAs 400kV Switchyard

1) CT Details: CT-12, Core-1 will be CT-12, Core- 5 for 87OA:

CT ratio =2000-1000-500/1A, Vk 4000-2000-1000 V, Ie 30-60-120 mA at Vk, Rct =10-5-2.5 @75 C.

2) CT-12, Core-2 will be CT-12, Core- 4 for 64RGT instead 51GT.

CT ratio =2000-1000-500/1A, Vk 4000-2000-1000 V, Ie 30-60-120 mA at Vk, Rct =10-5-2.5 @75 C.

f) Input to BHEL to prov ide CT parameter ofSiemens make 6.6KV Switchgear (1LSR01/2)

1) CT Details: CT-18A, 18B for 87UATA/B,

CT ratio =2500 /1A, Vk (40RCT +70V), Rct= 11 ohms @75 C. Ie 30 mA at Vk /2,

B. Please note the following forSingle Line Diagram

a) Please note followings Make have been provided in JPL project

1)GR1,GR2,64GIT,87OA,51NGT,51GT,64RGT,87UATA/B,51NUATA/B,51UATA/B,64UATA/B are Siemensmake. 2).60VT1/2/3,97G are AREVE/ABB Make

b) Refer CT-8, provide separate CTs for fo llowing:-

1) for Load Transducer with AVR( Auto-Channel-2)

2) for Transducer to DDCMIS connection.

c) Provide IVT before 64GIT,

d). Check & correct the equipment data as below: -

1) Xd of Generator =16.8%(instead of 15.5%).

2) %Z of GT = 15.1% 10%on 340 MVA base instead of 14.5%.

3) %Z of UAT = 10% 10%on 20 MVA base instead of 10% only.

4) KVA Rating of NGT = 75KVA instead of 50KVA.

5).NGR Rating= 0.3359 ohms (Taps at 0.25/ 0.29/ 0.3 ohms), 600A for 5min., 240V,

e). Correct the CT / VT/IVT details as commented elsewhere.

C. Please note the following forLogic Diagram

1) Delete Bus coupler Bay at 400KV Buses

2) Delete the line cum transfer bus in 400KV Main Bus-II.

3).Revise GT Connection with 400kV switchyard by means of D-Type one and half breakerscheme. Instead of I-Type arrangement. Also consider the 400KV breakers at Logic Diagram.

4) Please note that there is no GCB at 16.5kV level, Synchronization will be done at 400kVSwitchyard.