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118th PCM MAIL LIST

1) Chief Engineer (LD), MSETCL, Kalwa.Fax-27601769/65

2) Chief Engr. (Trans O&M), MSETCL, Bandra. Fax No. 022 26598587.

3) CE (W), MSEGCL, 3rd

floor, Prakash gad, Mumbai.

4) S.E. (T&C), MSETCL, Aurangabad Fax-0240-2234220 /2346290

5) S.E (T&C), MSETCL, Pune. Fax-9520-2617532/2612342

6) S.E. (T&C), MSETCL, Nagpur. Fax-95712-2234220

7) S.E.(T&C), MSETCL, Nasik Road Fax-0253-2462422

8) S.E.(T&C), MSETCL, Vashi Fax--022-27662055

9) S.E.(Gen.Tstg), MSPGCL,Eklahre, Nasik Fax-95253-2810496/2810499

10) S.E. (Task Force), MSPGCL, Nagpur Fax- 0712-2591717.

11) S.E.(TCC), MSETCL, Karad. Fax.No. 02164 255118

12) Chief Engineer (Gen), GSECL, H.O. Baroda. Fax-0265-5512129/2344537

13) Addl. C.E.(Testing), GETCO, Baroda. Fax-0265-2351218

14) Chief Engineer(LD), MPPTCL, Jabalpur. Fax-0761- 2664343 /2282632.

15) E.D. (T&C),MPPTCL, Jabalpur. fax-0761-2661696

16) Addl.C.E., MPPGCL, Jabalpur Fax- 0761-2660063/2665805

17) Chief Engineer (LD), CSPTCL, Bhilai. Fax-0788-2282632/0788-383633

18) C.E. (T&C), CSEB, Raipur.Fax-0771-4066988/07759-226227

19) EE (T) , CSPGCL- Fax.No. 07789-226227

20) S.E.(T&C), CSPTCL, Bhilai. Fax.No. 0788 2281

21) S.E.(T&C), CSPTCL, Raipur. Fax No.0771-4066988.

22) E.E.(T&C), CSPTCL, Bhilai. Fax No. -0788 2281561

23) EE, Division VIII (MRT),Elect. Dept; Goa Fax 0832-2735124.

24) Supdt.Engr., Electricity Dept., DNH, Silvasa. Fax : 0260-2642338

25) Executive Engr., Electricity Dept. DD. Fax : 0260-2250889

26) D.G.M.(O.S. ),N.T.P.C., Mumbai, Fax- 28216692

27) D.G.M.(EM), KSTPS, NTPC, Korba Fax 07759-233088/ 232440

28) DGM (EMD), VSTPS, NTPC, Vindhyachal Fax-07805-247713

29) DGM (EM-I), NTPC, SIPAT Fax-07752-246506/246691.

30) AGM(O&M), KGPP, Adityanagar, Surat Fax 0261-2861428/2861433

31) Sr.Supdt. (EM), Gandhar, NTPC Fax-02642-87402 / 87450

32) DGM (O.S.), WRLDC, Mumbai Fax-28235434

33) DGM, WRTS-I, POWERGRID, Nagpur.Fax-95712-641366/2641496

34) Addl General Manager, WRTS-II, POWERGRID, Baroda Fax-0265-2480952

35) SME (E), TAPS-3&4,Tarapur Fax 02525-282001/282073

36) Maintenance Superintendant, TAPS –1 & 2,Tarapur.Fax- 02525-282121

37) SME(E), NPCIL , Kakrapara Fax 02626-234266

38) GM(Maint.). TORRENT Power., Ahmedabad.Fax-079-27506679

39) AGM (ET&A),TPC, Trombay. Fax –022-66687088

40) Dy.Gen. Manager, Dahanu TPS Fax- 952528-222576

41) Vice President, Reliance Energy, Mumbai Fax-30094488

42) GM (Electrical), JPL, Raigarh. Fax.No.7767-281995,281993.

43) AGM(OS), NSPCL, New Delhi . Fax.No.011 26717363/26717366

44) Vice President, APL, Ahmedabad

45) GM, RGPPL, Anjanwel, Guhagar, Ratnagiri, Fax.No. 02359 241071

46) GM, JSW Energy Ltd., Jindal Mansion, Mumbai- Fax.No.022 23526400

47) GM, CGPL, Mundra. Fax.No. 02838 661188

48) Director (G M Division), CEA, New Delhi. Fax.No.011-26109750

1 Minutes of 118th Protection Committee of WRPC

MINUTES OF THE 118th

PROTECTION COMMITTEE MEETING OF WRPC HELD ON

19.07.2013 AT WRLDC MUMBAI.

The 118th

meeting of the Protection sub-Committee was held at WRLDC Mumbai on 19th

July 2013.

The list of participant is enclosed at Annex-1.

Shri S.D. Taksande, Member Secretary, WRPC welcomed Shri S.K. Negi Chairman TCC &

M.D.GETCO and the participants of the meeting. He thanked Shri S.K. Negi for sparing his valuable

time for guiding the participants of the meeting. He stated that various system security aspects were

discussed in the 2nd

NPC meeting held on 16.07.2013 at New Delhi. The region wise stages and

quantum of the UFR load shedding was discussed and finalized. CEA informed that the DPRs received

from other regions were scrutinized by CEA and the DPRs submitted by WR constituents would be

taken up for scrutiny and discrepancies if any would be communicated. He further stated that SPS for

Wardha flow gate, SPS for Adani HVDC and AC system and SPS for CGPL was finalized between the

intervening period of 117th

PCM and this meeting.

Shri S.K.Negi Chairman TCC & M.D. GETCO stated that he is privileged to address the esteem

technical forum of WR, where experts from the testing and protection area participate and share their

expertise and experience. He suggested that this sub-Committee should keep a follow up of the sub-

Committee recommendations and suggestions. These recommendations and suggestions would

minimize the frequency of the similar type of occurrences. System threats could be minimized through

proper co ordination among all the regional identities. He stated that all the utilities are facing skilled

man power crunch and further suggested that the skill development could be achieved through educating

the existing man power/engineers about the new technological developments in the field. This forum

should arrange seminars/workshops on emerging technologies in the field of system security.

ITEM NO.1: CONFIRMATION OF MINUTES OF 117th

PROTECTION COMMITTEE

MEETING.

Superintending Engineer (C&P), WRPC informed that the minutes of 117th

PCM, held on 03/04.06.2013

at CGPL Mundra were circulated vide WRPC letter No. WRPC/Protection/117PCM/2013-14/7858

dated 05.07.2013. No comments have been received.

PGCIL representative as regards to the recording at the last para of Item 7.5 regarding review of relay

setting for 400kV D/C Pirana(PG)-Pirana (Torrent) line stated that the recordings of the last para are not

consistent with the discussion and the relay settings at their ends are in order.

PGCIL representative informed that on both the occasions of tripping of the above line from their end on


DEF, the DR recorded considerable phase to phase fault currents. Further he informed that the section of

the line is multi circuit line and adequate clearances are not maintained. Therefore Torrent should

inspect the line for clearances.

Torrent representative informed that they would inspect the line and would confirm whether there is any

clearance issue involved, within one month.

It was decided that a meeting between GETCO, PGCIL and Torrent shall be held to resolve the issue.

It was decided that the last para of Item 7.5 regarding review of relay setting for 400kV D/C Pirana(PG)-

Pirana (Torrent) line would be amended as,

“PGCIL representative informed that on both the occasions of tripping of the above line from

their end on DEF, the DR recorded considerable phase to phase fault currents. Further he

informed that the section of the line is multi circuit line and adequate clearances are not

maintained. Therefore Torrent should inspect the line for clearances.”

With the above amendment the minutes of the meeting circulated vide above letter was confirmed.

ITEM NO.2: SYSTEM DISTURBANCES

2.1: System disturbances in CSPTCL/CSPGCL system.

NIL

2.2: System disturbances in GETCO/GSECL system.

NIL

2.3: System disturbances in MPPTCL/MPPGCL system.

2.3.1 : Occurrence on 24.05. 2013 at 400kV Bina S/S,:

MPPTCL representative informed that on 24.05.13 at around 04:39 Hrs, ‘Y’ – Phase CT of 220

KV Bina – Bina Interconnector Ckt. – II got burst at 400KV S/s Bina, which in turn damaged the PI of

line and Auxiliary Bus side isolators and resulted in tripping of feeders/transformers mostly from remote

ends in Zone-II, except 220kV Guna-II.The 220kV Bus Tie tripped on E/F and also 220kV Incomers of

315MVA T/F-I&III tripped on Definite time delay O/C protection. No tripping occurred on 400 KV

Side at 400 KV S/s Bina. At 400 KV S/s Bina, Bus Bar protection was out of service and was taken in

Ckt. on 27.05.2013.


He further informed that, initially Y phase CB pole of 220 KV IC II tripped at 400 KV S/s end, isolated

the fault, same was isolated from other ends in Zone II time. But due to fire and flames and charged

status of other two poles, high resistive arcing persisted which was cleared in 926 msec with tripping

of other two poles of 220 KV IC II CB.

On dt. 27.05.13, 220 KV Bus Bar Protection Scheme (GE make 90) commissioned at 400 KV S/s Bina.

It was under commissioning stage during above occurrence.

WRLDC representative informed that they have analyzed the DR of the event recorded at Satna end, and

it is found that the fault current persisted for more than 1 sec. Therefore it is suspected that the fault was

not cleared within Zone-2 timings.

System was made normal by charging the 400/220 KV, 315 MVA X-mer – I at 05:05 Hrs. and all the

tripped elements were restored by 06:40hrs.

After replacing CT of ‘Y’ – Phase, the Interconnector – II was charged at 17:38 Hrs on 25.05.2013.

There was no Load Loss during the above tripping.

Report received from MPPTCL is enclosed at Annex.-2.3.1

Committee felt that the fault due to failure of Y phase CT was sensed at remote ends in Zone-II,

however due to fumes and flames and two poles remained in service the high resistive arcing

persisted for around 926msec as seen from the DR submitted by MPPTCL, till the same was

cleared with tripping of these two poles of 220kV I/C-II Circuit Breaker. Bus Bar protection

would have isolated the fault selectively. Therefore Bus Bar protection should be brought into

service at the earliest. Also the DPS at Guna end should be checked.

2.4: System disturbances in MSETCL/MSPGCL system.

2.4.1: Occurrence on 30.05.2013 at 400/220/100/22 kV Padghe sub-station.

MSETCL representative informed that on 30.05.2013 at 18:06hrs, at 400kV Padghe s/s, 220 kV Bus II -

Y-phase PT burst & caught fire resulting in to tripping of all the 220kV feeders & equipments connected

to 220 kV Main- Bus-I &II (A &B Bus ). This resulted into loss of load to the tune of 825 MW on

220kV/100 kV /22 kV level at various s/s feeding from Padghe s/s.


The Relay Indications were as follows:

220 kV Bus Bar Bus II ABB RADSS: R, S, T,U , Bus Bar Trip relays 96T for B Bus operated

220 kV Bus Bar Bus I ABB RADSS: R, S, T,U , Bus Bar Trip relays 96T for A Bus operated

220 kV Bus Coupler: Bus bar Main I & II operated.

3x105 MVA, 400/220/33 kV ICT I: T/F overloads Alarm, HV B/U optd.

315 MVA, 400/220/33 kV ICT III: TF Overload Alarm, HV B/U operated.

Load Trimming Relay: 400kV HV Load Trimming Relay Operated.

The 200MVA, 220/100KV, VIJAI ICT III HV was on TBC through A Bus due to ongoing work of

replacement of isolators under LES scheme. The 220kV Bus II PT and TBC CB are very closely located

in TBC bay. Due to severe bursting of PT, fumes/flames/oil and damaged parts spread & spilt over the

adjacent R & B phase PT & all three poles of TBC Breaker.

Complete failure of 220 /100/22 kV supply occurred at Padghe s/s. The 400 kV remained in service. The

Bhatsa / Vajara Hydro Generation of 12MW connected to 100KV Shahapur s/s was also affected.

Due to tripping of 400 KV ICT-II & IV connected on faulty Bus-II, the 400 kV ICT-I & III connected to

healthy bus-I got overloaded & HV O/C started. Therefore, overload Alarm & load trimming scheme

also operated (Stage- I: 1 sec delay). However the load relief through 100 kV Bhivandi I /II (116 MW)

was not sufficient to arrest the ICT overload & therefore HV O/C remained in picked up condition.

The ABB make, 220kV RADSS bus bar protection of 220kV Main bus-I-A did not operate immediately

due to the developing fault as it was confirmed from operation of Reverse Zone-4 fault (300 msec) of

220 kV Temghar-I & Jindal feeder.

Meanwhile, in the racing, 400 kV ICT –I& III tripped on HV O/C protection as its O/C was already in

Picked up condition.

The simultaneous operation of Bus bar protection of Bus –I occurred which resulted into tripping of all

the feeders/equipments connected to Bus –I.

HVDC pole-I & II was in service with 700 MW & Pole-I tripped on ‘Main circuit flow low trip’ while

Pole-II remained in service

Due to tripping of all the feeders & equipments connected to both 220 kV buses, total 220 kV supply

failed which resulted in loss of downstream 100 & 22 kV supply also. The various s/s feeding from

Padghe s/s were affected & total loss of load @ 821 MW for about 1 hrs to 1 ½ hrs.


After extinguishing of fire & isolation of faulty PT, the 220kV Bus-I PT supply was extended to all

220kV Bus II connected lines and transformers. The 220kV Main Bus I bus was charged through

400/220kV 315 MVA ICT III at 18:27 HRS. The 220kV Main Bus II was charged through bus coupler

at 18:43hrs.

As regards to tripping of HVDC Pole-I on “Main circuit flow low trip” MSETCL representative

clarified this might have happened due to loss of auxiliary, since one of the DG back up might

have picked up late.

Committee observed that the trippings were in order. However the failure of instrument

transformers at such vital S/S is a cause of concern and the condition/test results of Instrument

transformers should be monitored closely.

2.4.2 : Occurrence on 22.05.2013 at 220 KV Deepnagar S/S.

MSETCL representative informed that on 22.05.2013 at 22:49hrs R phase CT of GT-5 bay connected to

Bus-I busted resulting into operation of Bus Bar protection of 400kV Main Bus-I. This led to tripping of

elements connected to 400kV Bus-I. At the same time, B phase pole of Main CB of 400kV Deepnagar-

Bhusawal II failed and got busted. The bus bar protection for Main Bus-2 also operated this resulted in

complete supply failure at 400kV Deepnagar S/S.

The generation loss due to above tripping was around 531 MW.

All the tripped elements were restored by 00:44hrs of 23.05.2013.

Committee observed that the trippings were in order. However condition monitoring of

Instrument Transformers and CBs should be closely done.

2.4.3 : Occurrence on 20.06.2013 at 220 KV GCR Eklahara S/S.

MSETCL representative informed that on 20.06.2013 at 02:49 hrs., 220KV B phase CT (ABB

make commissioning 21.06.2003) of Unit 5 side Burst. This resulted in bus fault in bus bar protection

zones ‘B’ & ‘C’ (Overlap zone as shown in SLD). The bus differential relays for zone B, C and Check

zone (87BC , 87CC & 87CHC) operated correctly for this fault and extended trip command to bus bar

trip relays of Zone ‘B’ & ‘C’. As the through fault was very close to the Zone A Bus. Differential relay

(87AC) also operated & extended trip command to bus bar trip relays of Zone ‘A’.

All 220 KV Circuit Breakers in Zone A, B & C tripped.

In view of operation of Zone A bus differential relay for this through fault, the detailed

investigation being carried out for Zone A CT circuit for each bay by availing outages.


Failed CT was of ABB make commissioned on 21.06.2003. Last Tan Delta Results On dtd. 29.12.2012

:- C=1204 pF & Tan Delta =0.355%.

Generation Loss Generation U3- 132MW, Generation U4- 135MW, Generation U5- 140MW.

In view of the failure of B-ph CT of Bus-section-III; other 5 Nos CTs of Bus-section-III were tested.

After testing, the tandelta value of R-ph & B-ph CTs SCT make of Bus-section-III Generation Unit-IV

side were found on the higher side, hence these CTs were replaced after testing by new CTs.

The 220KV Bus-Bar protection provided in EKL GCR S/S is EE make CAG commissioned in 1979.

The new ER make Numerical Bus-Bar protection scheme is tested & being commissioned shortly.

The Tan delta values of SCT make CTs found increased (beyond 0.7%) in short span of service.

Reputed make CTs to be installed being generation attached substation to avoid generation loss.

Committee observed that the BB Zone-A, should not have operated for fault out side its coverage.

The same should be tested. Further the condition monitoring of Instrument Transformers should

be closely done.

2.4.4 :Occurrence on 02.05.2013 at 400/220kV Kalwa Substation.

MSETCL representative informed that on 02.05.2013 at 16:57 Hrs, IPS tube between Bus-post & C-bus

isolator in respect of 400kV Lonikand bay fell and touches to bus post structure, creating bus fault at

400kV Kalwa substation. The 400kV Main bus-2 bus bar protection operated correctly. All the 400kV

lines & ICTs connected to 400kV Main bus-2 tripped. The 400kV Lonikand bay is connected to 400kV

Main bus-2 at Kalwa sub-station. The detail occurrence is as below::

The Indications appeared were as under :-

400 kV Bus Bar Bus- II ABB RADSS : S: Y-ph, T: B-ph, U: Trip

Bus Bar Trip relays 96T: 3 x 167MVA, 400/220/33 kV ICT-III, 400kV Lonikand , 400kV Padghe-I, 1 x

167MVA, 400/220/33 kV Spare ICT, 400kV Bus-coupler

The 400kV Main bus-2 bus bar protection operated, since the 400kV Lonikand was connected to 400kV

Main bus-2 at Kalwa s/s. All the 400kV lines & ICTs connected to 400kV Main bus -2 tripped along

with bus coupler.

The work of replacement of 400 kV C-bus isolator of Lonikand bay was carried out on 08.11.2012.

The failure of IPS tube may be due to week holding of IPS tube in the grip of new clamp which have

less grip area and less strength as compared to old clamp. This got further weakened during service

condition due to through fault currents.

The restoration was completed by 17:12hrs of 02.05.2013.

Committee observed that the tripping was in order.


2.5 Follow up of recommendations of PCM on past occurrences:

117th

PCM :

2.1: System disturbances in CSPTCL/CSPGCL system.

2.1.1 : Occurrence on 28.03.2013 at 400kV ACBIL, Chhattisgarh :

The DPS of both the lines have overreached, therefore the line settings of 400kV ACBIL-Bilaspur 1 & 2

lines needs to be reviewed.

2.1.2 : Occurrence on 02.04.2013 at 400kV LANCO (Pathadi) TPP, Chhattisgarh

Committee felt that though the operation of Bus bar protection was in order, tripping of 400 kV Pathadi –

Korba line in Zone -1 from Korba end was undesirable. The relay settings of 400 kV Pathadi – Korba line at

Korba end need to be checked for over reaching and corrected if required.

2.1.3 : Occurrence on 19.03.2013 at 220/132 kV Raigarh S/S, Chhattisgarh:

Commissioning of Bus Bar protection at 220 kV Raigarh substation at the earliest.

2.1.4.Occurrence on 28.01.2013 at Balco, Chhattisgarh:

WRLDC may do complete analysis/study to ascertain violation of system parameters in study/analysis, prior

to giving clearance to open the lines.

2.2. System disturbances in GETCO/GSECL system.

2.2.1 : Occurrence on 21.02.2013 at 220kV Vapi (GETCO) S/S :

Committee felt that the tripping of 220kV Vapi (Getco) – Bhilad & Vapi (Getco) – Tarapur on operation of

Back-up relay and Zone 2 from remote ends ahead of LBB protection was undesirable. The relay settings of

these lines need to be tested and relay settings be coordinated appropriately. Also the LBB relay may be

tested for time settings, since the above lines connected to Bus-I tripped on B/u & Zone-2 timings.

2.2.2 : Occurrence on 03.02.2013 at Ukai Thermal Power Plant, Gujarat:

Committee observed that the transformer differential protection/Bus Bar protection should have

operated. The Bus Bar protection/LBB protection should be checked and tested.

2.3. System disturbances in MPPTCL/MPPGCL system.

2.3.1 : Occurrence on 08.04.2013 at ATPS Chachai :

The BB protection should be put into service at the earliest.

2.3.2 : Occurrence on 12.04.2013 at ATPS Chachai

Committee felt that in absence of BB protection, tripping of lines from remote ends was in order. However

tripping of 220kV ATPS-Chahchai –Sidhi line in Zone 1 & SOTF from Sidhi end and 132kV Anuppur


feeder. No.2 on E/F was not desirable. The relay settings of ATPS-Chahchai –Sidhi line and 132kV Anuppur

feeder. No.2 should be checked/tested.

2.3.3 : Occurrence on 14.04.2013 at ATPS Chachai

The BB protection should be put into service at the earliest.

2.3.4 : Occurrence on 16.03.2013 at 220kV Pitampur

Committee felt that due care should be taken during relay settings. Further line PTs should be installed and

wired up for line protections.

2.3.5 : Occurrence on 29.01.2013 at 220kV Pitampur S/S

Committee felt that OLTC Buchholz relay of T/F shouldn’t have operated. Tripping of T/F-II on over current

due to insufficient load trimming was in order. However excess load not in commensurate with the

transformer loading capacity should be included in the load trimming scheme.

2.3.6 : Occurence on 18.04.13 at 220kV Pithampur S/S

Committee felt that there was a problem in the logic of Bus selection. Also the time setting of LBB relay was

wrong, resulting in initiation of trip signal to both buses and same should be corrected.

2.3.9 : Occurrence on 15.01.2013at 220kV Jabalpur Nayagaon S/S

The over flux relay of transformer might have operated due to high voltages. Over flux setting of transformer

need to be tested.

2.3.12 : Occurrence on 23.03.2013 at 220kV Birsingpur S/ S

Committee observed that the bus-bar protection scheme/module was faulty. This un-cleared fault led to

fall in voltage below hold on voltages of the contactors of auxiliaries, resulting in failure of auxiliaries

thereby tripping of unit 1 & 3. MPPTCL representative informed that the new BB protection scheme is

under commissioning.

2.3.13 : Occurrence on 19.11.2012 at Rajgarh

Committee observed that though tripping was in order. However it was recommended that WRLDC may

permit opening of only one line at a time out of Sujalpur-Rajgarh –I & II, since the loads connected

through these lines are radial loads.

2.3.15 : Occurence on 29.04.13 at 220kV Nagda S/S

Committee observed that tripping was in order. It was recommended MPPTCL should pursue

suitable/timely preventive and routine maintenace of CTs.

2.3.16 : Occurence on 21.03.13 at 220kV Pandhurna S/S

Committee observed that tripping was in order. It was recommended MPPTCL should pursue

suitable/timely preventive and routine maintenace of CTs.


2.3.17 : Occurrence on 26.04.13at 220kV Barwaha S/S

Committee observed that the tripping of lines from remote ends due to faulty BB protection scheme was

in order. MPPTCL was requested to repair/replace the faulty BB protection scheme at the earliest.

Further the tripping of Unit nos. 2, 3, 4, 5 on phase over current protection was undesirable and therefore

MPPTCL/MPPGCL should review the settings/ test the O/C relays.

MPPTCL representative informed that replacement of the faulty bus bar protection scheme is under

progress.

2.3.18 : Occurence on 27.04.13 at 220kV Barwaha S/S

The observations of the Committee were as recorded at Item 2.3.17.

2.3.20 : Occurence on 28.02.13 at 220kV Malanpur S/S

Committee observed that operation of E/F relay at Malanpur and operation of DPR in Zone-II from

Gwalior end of 220kV Malanpur-Gwalior line on line fault was undesirable. Further tripping of 220kV

Malanpur-Auriya from both ends in Z-I was also undesirable.

2.3.22 : Occurence on 30.04.13 at 400kV ISPS S/S

Committee felt that BB protection at ISPS S/S should have operated.

2.4: System disturbances in MSETCL/MSPGCL system.

2.4.4 : Occurrence on 7.02.2013 at 220 kV Miraj S/stn..

Committee observed that operation of BB protection for through fault was not desirable and suggested

to review the bias setting of BB protection.

2.4.5 : Occurrence on 20.01.2013 at 220kV Lonikand S/S.:

Committee felt that the faulty LBB relay should be replaced.

2.4.9 : Occurrence on 13.03.2013 at 220kV Sonkhar s/s.

Committee observed that tripping of elements from remote ends in absence of BB protection was in

order and expressed that the BB protection be put into service at the earliest.

2.4.14 : Occurrence on 02.05.2013 at 220 kV GCR Eklahare S/S.

Committee observed that the operation of Zone-A of the BB protection was undesirable and therefore

the same should be checked.

The follow up actions could not be discussed due to paucity of time and the same shall be taken up

in the next meeting. Utilitities concerned are requested to submit the update on the same in the

next PCM.


ITEM NO. 3: Tripping of lines / ICTs:

The incidences of tripping of lines and ICTs during the period 01-05-2013 to 30-06-2013 are enclosed at

Annexure–3.

Committee may like to note.

ITEM NO. 4: Status of implementation in WR on Recommendations of Report on Grid

disturbance on 30th

and 31st July 2012

The Status of implementation in WR on Recommendations of Report on Grid disturbance on 30th

and

31st July 2012 as on 30.07.2013 is given at Annexure-4.

In the 117th

PCM it was informed that CEA vide letter No. 6/AI/DST/GM-2013/441-449 dated

10.05.2013 has forwarded formats for collecting information of status of action taken on the

recommendations of the Enquiry Committee. The updated status of implementation of various

recommendations of the grid disturbance enquiry committee as on 1st & 15

th of each month is required to

be forwarded to CEA by RPCs by 3rd

& 17th

of every month regularly.

1) Information in Formats 1 to 3 is to be furnished by STU and CTU for month by 1st and 15

th

of the month.

2) Information in Format 4 is to be furnished by SLDCs/ WRLDC POSOCO for the month by

1st and 15

th of the month.

3) Information in Format 5, 7 & 8 is to be furnished by WRLDC POSOCO for the month by 1st

and 15th

of the month.

4) Information in Format 6 is to be furnished by CTU for the month by 1st and 15

th of the

month.

In the 117th

PCM it was decided that the above information may please be forwarded through the

nodal officer of the above organisations to WRPC.

Nodal officers identified for submission of data were as follows;

1. WRLDC : Shri P.Pentayya GM WRLDC

2. PGCIL-I : DGM(OS)

3. PGCIL-II: DGM(OS)

4. NTPC WR-II : Shri D.Roychowdhari AGM(OS) & A.K.Chandelia DGM(OS)

5. GETCO STU : Shri S.A.Patel.


6. GETCO SLDC : Shri B.B.Mehta, CE SLDC.

7. MSETCL STU : Shri Rajurkar SE

8. MSETCL SLDC : CE SLDC

9. MPPTCL STU : Shri Jain, CE (T&C)

10. MPPTCL SLDC:Shri P.A.R Bende CE SLDC

11. CSPTCL STU:Shri Rehman SE(T&C)

12. CSPTCL SLDC: Shri K.S.Manotia CE SLDC.

It was intimated that the information in the formats was received from WRLDC for the period

ending 15.06.2013. Other utilities have not forwarded the data. CEA is pressing hard for

submission of the data. The matter was also flagged in the 2nd

NPC meeting.

Committee requested utilities to forward the up dated data by 1st and 15

th of the month without

fail.

ITEM NO. 5: Zone 3 settings of Distance Protection Schemes:

Back Ground : CEA have issued Manual on Transmission Planning Criteria which is effective from

01.02.2013 (the same is available at CEA website). Under para 20 of the “Manual on Transmission

Planning Criteria”, guidelines on zone-III setting to avoid tripping of lines in extreme loading conditions

has been given as follows

Quote

20 Guidelines for consideration of zone-3 settings

20.1 In some transmission lines, the Zone-3 relay setting may be such that it may trip under extreme

loading condition. The transmission utilities should identify such relay settings and reset it at a value so

that they do not trip at extreme loading of the line. For this purpose, the extreme loading may be taken as

120% of thermal current loading limit and assuming 0.9 per unit voltage (i.e. 360kV for 400kV system,

689kV for 765kV system). In case it is not practical to set the Zone-3 in the relay to take care of above,

the transmission licensee/owner shall inform CEA, CTU/STU and RLDC/SLDC along with setting

(primary impedence) value of the relay. Mitigating measures shall be taken at the earliest and till such

time the permissible line loading for such lines would be the limit as calculated from relay impedence

assuming 0.95 pu voltage, provided it is permitted by stability and voltage limit considerations as

assessed through appropriate system studies.


Unquote.

The above guidelines were circulated to the WR constituents for implementation by WRPC vide letter

WRPC/Prot/GD/2012/289 dated 08.03.2013.

In the 117th

PCM the matter was discussed and all state utilities confirmed that the Zone-3 settings

adopted are generally higher than the line loadability limits given in para 20 of the “Manual on

Transmission Planning Criteria” . Committee also expressed that all the utilities shall check Zone-

3 settings for line loadability given in the “Manual on Transmission Planning Criteria”, as above.

Where ever the Zone-3 settings violate the line loadability limits, the utility shall inform the same

to CEA under intimation to WRPC.

All the utilities confirmed that they have already taken care of the above lodability limits in

deciding the Zone-3 settings.

MS, WRPC stated that during 2nd

NPC meeting at New Delhi it was suggested that STUs should

furnish the data regarding Zone – III settings in respect of intra-state lines requiring relay

coordination with CTU network. He requested STUs to furnish such data directly to CTU under

intimation to WRPC.

Committee noted.

ITEM NO. 6: Other Items:

6.1 : SPS for CGPL units :

Back ground : GETCO vide letter No SLDC/CE/MIS/CGPL-SPS/T-1184 dated 01.04.2013, have

intimated that there are six circuits for evacuation of power from CGPL, Mundra which has an installed

capacity of 4000MW(5x800MW) namely: 400kV D/C CGPL-Bhachau (PG)-Vadavi (Triple snowbird

conductor), 400kV D/C CGPL-Chorania (Triple snowbird conductor) & 400kV D/C CGPL-Jetpur

(Triple snowbird conductor). An SPS is required to be implemented for specic contingencies as given

below;

A) If any one circuit of 400kV D/C CGPL-Bhachau (PG) or any one circuit of 400kV D/C CGPL-

Chorania line trips, then it is very much necessary to back down the generation from CGPL by at least

600-700MW or trip the highest generating unit automatically through SPS so that loading on the

remaining lines does not rise beyond.


B) If both circuits of 400kV D/C CGPL-Bhachau (PG) line or both circuits of 400kV D/C CGPL-

Chorania line trip, then two units having the highest quantum of generation should trip automatically

through SPS.

Further, GETCO vide letter No SLDC/CE/MIS/Mundra-UMPP/SPS/T-1581 dated 15.05.2013, have

proposed following schemes for implementation of SPS for CGPL units in case of overloading of the

outlet lines from CGPL Mundra.

1. Loading on any outlet line of CGPL reaches 900MW for more than 10 seconds, there should be an

alarm.

2. Loading on any outlet line of CGPL reaches 1000MW for more than 3 seconds, RBS should

activate for reducing generation by 500MW in not more than 5 minutes.

3. Loading on any outlet line of CGPL reaches 1200MW, then there should be instantaneous tripping

of one unit having the maximum generation on bar.

In the 117th

PCM following was decided;

SPS for CGPL

CGPL Chorania-1 Chorania-2 Bhachau-1 Bhachau-2 Jetpur-1 Jetpur-2 Action at CGPL

1 >3100 X X

>1500

Trip mills this will reduce generation by @500MW

2 >3100

X X >1500

3 >3100 X

X

>1500

4 >3100

X

X >1500

5 >3100 X

X >1500

6 >3100

X X

>1500

7 >3100

>1200 Alarm for reduction in generation so that the Jetpur lines loadings are maintained around 1200MW

X- indicates tripping of the line.

The above recommendations of PCM was discussed in the 23rd

WRPC meeting and it was decided

that instead of tripping of coal mills, Unit tripping was suggested for conditions 1-6 above, as

backing down is a slow process and would not give instantaneous result as required by SPS.

CGPL representative stated that they do not agree for tripping the unit.

Shri S.K.Negi Chairman TCC & MD GETCO stated that the matter was finalized in the 23rd

WRPC meeting and therefore disagreement if any on the decision of WRPC shall be taken up in

WRPC forum.


6.2 :Over-Voltage Protection for Transmission lines in Western Region

Back ground : WRLDC vide letter WRLDC/MO-I/1658/2012/8960 dtd. 15.05.2013 have intimated

that, considerable number of critical 765/400 kV lines is being kept out for containing High voltage.

Also there are several cases of multiple tripping of feeders emanating from a single node on over

voltage. Multiple tripping on O/V at one node or in a single corridor may lead to transmission depletion

adversely affecting grid security. In such cases the drop off to pick ratio should be increased to 99%

while the over-voltage rating should be changed to 112 % to increase the reliability of the grid. The high

drop-off to pick-up ratio of the O/V relays (say 99% and above) ensure quick reset of the relay so as to

avoid multiple tripping of feeders on over voltage.

For a standalone static type of relay the drop-off to pick-up ratio may be relooked and modified to

99% at all locations in WR grid by the respective utilities / constituents.

In case the relay is of multi-function numerical type where the over voltage function is being

utilized for O/V protection the vendor may be requested by the concerned utility to modify the ratio

(drop-off to pick up) to 99%.

Following nodes in western region are identified as high voltage node where line trip on over voltage

protection: Chandrapur, Parli, Raigarh, Raipur, Wardha, Indirasagar, Kolhapur, Solapur, Karad, Rajgarh,

Khandwa, Itarsi, Dhule, Seoni, Nagda , Kasor, Bhadrawati, Akola. Hence the above changes may be

discussed in the meeting and implemented on priority. Matter may be taken as most urgent in view of

reliable and secured grid operation.

In the 117th

PCM, the Committee discussed the matter in length as regards to logic implemented in the

over voltage relays vis a vis the performance of the relays in field as follows;

1. In general the O/V relays are set for drop off to pick up ratio of 95%.

2. For a typical bus having 10 outgoing lines, with nominal voltage of 400kV, the pick up voltage of

the relay at 110%, would be 440kV and the drop off voltage of the relay would be 418kV.

3. In case the voltage at the bus touches 440kV, all the O/V relays would pick up. If the voltage

remains above 418kV for period more than the time delay setting of the relay, all the lines would trip.

4. In case, one of the lines trip on O/V, for a typical bus the voltage would fall by 1% (i.e. the bus

voltage would fall to 435.6kV), which is still above the drop off voltage of 418kV and therefore more

outgoing lines (3 to 4 lines) from the bus would trip, till the bus voltage falls below 418kV, thereby

resetting the picked up over voltage relays of the lines in service. In practice, it has been observed that

multiple lines from the same substation are not tripping on O/V.

5. As seen from the above performance of the O/V relays, the logic implemented in the O/V relays as regards

to the drop off to pick up ratio may be different than the conventional understanding about this ratio.


In the 117th

PCM, it was concluded that even after tripping of one of the line on O/V, the bus voltages

drops by only 1% and under this scenario, the O/V relays on other lines should not drop off and should

trip on O/V, if the drop off to pick up ratio set is 95%. In field this is not happening, suggesting that the

O/V logic needs to be checked. MSETCL was requested to look into the details of the logic by carrying

out tests on the different make O/V relays. The conclusions would be put up before next PCM.

MSETCL representative stated that they have identified high voltage nodes in their system.

Further they have taken up the testing of CVTs for errors, since they have noticed that many

trippings on O/V have occurred due to errors in CVT.

It was intimated that max drop off to pick up settable ratio available is 99.5% for ABB REL 670

relays, 99% in Siemens make relays and up to 98% in Areva relays. In the older version Areva

relays the same is settable for 95%.

WRLDC representative intimated that recently tripping of multiple lines connected to single node

has been observed (tripping of lines at Akola). Therefore the drop off to pick up voltage shall be

set to 99%, so that the relay would not trip the line if the voltage falls by 1% below 440kV (i.e.

110%) and multiple line trippings emanating from single node would not trip.

It was informed that the maximum continuous rating of the equipments in the system is around

5% above the nominal voltage (i.e. 420kV). Further the drop off to pick up ratio hysteresis is set

not just to inhibit the relay from operating but while deciding the hysteresis following factors are

required to be considered;

(i) The basic insulation level on which the system equipments are designed.

(ii) Time to settle down the system voltages.

(iii) Tripping of breakers around the safe voltage limits.

Therefore adopting the setting of drop off to pick up ratio to 99%, would ensure that the line

would trip (breaker opening) above 435kV, which is dangerous.

Committee felt that the drop off to pick up ratio be set around 97%.

Committee suggested the following remedial measures;

1. The overvoltage trip setting shall be graded for magnitude and time at the nodes where

sustained over voltage above nominal voltage is observed by the utilities and the settings adopted

be communicated to WRPC. The time delayed overvoltage trip setting shall not exceed 110%.

2. Manual control for overvoltage shall start at 415kV and manual opening of lines on

overvoltage should stop at 430kV.

3. WRLDC would carry out operation studies to identify over voltage nodes for manual control

at 415kV, 420kV, 425kV and 430kV.


4. WRLDC would carry out operation studies for time co-ordination of over voltage settings.

5. In addition to the lines already identified for over voltage tripping some more lines need to

be identified in consultation with utilities as in present scenario after exhausting MVAR

absorption by generator, line opening is only the option left to operator to contain high voltage.

6.3 : Status of Bus Coupler and Bus Bar protections at S/s

Back Ground : WRLDC vide letter WRLDC/MO-I/1658/2012/8960 dtd. 15.05.2013, have intimated

that, there has been several occasions in the grid when the Bus Couplers and Bus-Bar Protections are

kept out at substation without any intimation to WRLDC/SLDCs. In case of Bus coupler being kept out

of service, all the feeders are connected on both buses. During any fault on one of the bus, it will lead to

tripping of all the feeders as the fault will be fed to both buses. On the same, if Bus bar protection is kept

out of service, any fault on either of bus will led to tripping of feeders on both buses.

On 10-11-2012, 400 kV Birsinghpur Bus bar protection was kept out of service for testing without any

intimation to WRLDC/MP-SLDC. All the feeders tripped from both buses due to bus fault on BUS-II.

Also during occurrence at 220 kV Raigarh (CSPTCL) ,it was found that Bus coupler and bus-bar

protection are not in service and all feeders were connected on both the buses. During the fault on Bus II

on 19-03-2013, all the feeders tripped from remote end.

All the constituents are required to give the intimation to WRLDC and their respective SLDCs if

keeping the bus-coupler / Transfer Bus-Coupler/Bus-bar protection out of service. Also it is advised to

give the details of transmission elements in the substation which are out of service to WRLDC/SLDCs.

The status as informed by utilities with regards to above is as follows:

GETCO representative informed that BB protection is installed at all 400kV S/Ss., and 7 nos of

220kV S/S have single Bus system and BB protection would be provided. MSETCL representative

informed that BB protection is installed at all 400kV S/Ss. & 220kV S/S. MSPGCL representative

informed that BB protection is installed at all 400kV S/Ss., and at 3 nos of 220kV S/S BB

protection would be provided. MPPTCL representative informed that BB protection is installed at

all 400kV S/Ss., and out of 55nos of 220kV S/Ss, at 29nos of S/Ss BB protection have been provided

and at 28 nos (these are mostly single bus S/Ss) of 220kV S/Ss BB protection scheme would be

provided. CSPTCL representative informed that procurement of BB protection at 5 nos of S/S has

been started and at 11nos of S/Ss, the same has been provided.

Chairman TCC stated that the Bus Bar protection schemes should be provided by the respective

utility at the earliest, without expecting funding under R&U from MoP, GoI.


6.4 : Time synchronisation, non-working of DR and Main-2 of Ranchodpura line-2 at Dehgam S/S.

Back Ground : PGCIL vide letter WRTS II/O&M/273/AV/1211 dated 30.03.2013 &

WRTS/DEH/SS/385/113 dtd. 28.01.2012, have intimated that the pending protection issues related with

GETCO bays at Dehgam S/S have not been attended so far and requested GETCO for rectification of

the following issues;

(i) Main-2 Distance Protection Relay (Siemens make 7SA522) of 400kV Dehgam-Ranchodpura

feeder is faulty since April 2011.

(ii) In all the 400kV GETCO bays (Ranchodpura-1&2, Soja,Wanakbori) at Dehgam S/S, both Main-1

& Main-2 DPRs are of same make and principle (i.e. Siemens make & 7SA522 model). The same needs

to be replaced.

(iii) The existing DR & its PC are not working and have become obsolete. Therefore DR needs to be

configured in Main-1/Main-2 protection along with wiring of digital inputs & GPS time

synchronization.

GETCO representative as regards to (i), informed that REL 670-4nos of relays with time

synchronisation would be taken into service shortly.

6.5 : Auto recloser of 400kV Satpura-Koradi line:

Back Ground : MPPTCL vide letter No. 07-05/STP-79/487 dtd. 15.02.13, have intimated that there is a

repeated failure of auto reclose of 400kV of 400kV Satpura-Koradi line at Satpura end, since the auto

reclose from Koradi end was successful on transient faults on line and requested PGCIL to attend the

failure of the auto reclose at Satpura S/S.

PGCIL representative, in the 117th

PCM informed that A/R scheme would be replaced by July

end.

PGCIL representative informed that the circuit breaker replacement has been undertaken and on

availability of T/B the A/R will be commissioned. The same is expected to be commissioned in

August 2013.

6.5 : SPS for Wardha flow gate:

A meeting was held on 26/06/2013 at Mumbai, to discuss the control of power flow in the Wardha flow

gate due to injection of power by the embedded generators in Maharashtra system at 400kV Wardha

S/S.


Salient features of the SPS agreed in the meeting are as follows;

a. For implementation of the scheme line loading limit of Akola – Wardha and Parli –Wardha

considered is approximately 570MW per circuit and 670MW per circuit respectively.

b. Since NTPC Mauda on the Wardha corridor has been excluded from generation control for

controlling the power flow on the Wardha gate and M/s APL Tiroda have declared 3 units of 660MW

into commercial operation and therefore having a significant injection at 400kV Wardha S/S,the SPS

would control the generation at APL Tiroda only.

c. The amount of reduction of power flow on Wardha gate is ½ times the reduction of generation at APL

Tiroda, as per the sensitivity studies of WRLDC and the same was accepted.

d. When all outlets are available at Wardha, as per the line limits power flow from 400kV

Wardha‐Akola D/C and 400kV Wardha‐Parli D/C shall be restricted to 2480MW by equivalent

reduction/backing down of generation at APL Tiroda (i.e. twice the flow exceeding 2480MW).

e. Tripping of any one line out of 400kV Wardha‐Akola D/C and 400kV Wardha‐Parli D/C, the flow

gate margin adjusted at Wardha would be 2480MW minus the limit assigned to the tripped line as per a)

above.

f. Tripping of 400kV Wardha‐Akola D/C flow gate margin adjusted at Wardha would be 2480MW

minus 1140MW. The immediate generation back down at APL Tiroda shall be 260MW irrespective of

flow on Wardha gate.

g. Tripping of one 660MW unit with tripping of either both Wardha‐ Parli lines or one Wardha‐Parli and

one Wardha‐Akola lines, if the power flow through the Wardha gate is exceeding the adjusted margin as

per a) above by more than 500MW.

The above scheme would be reviewed for following change in system configuration in WR

h. The 400kV Chandrapur‐Warora line is commissioned.

i. When Parli generation comes and RGPPL generation picks up substantially.

j. Commissioning of Tiroda‐Akola‐Aurangabad 765kV corridor.

k. Synchronization of SR with the NEW grid.

Committee noted.


Supplementary Agenda Items:

1. AUFLS Quantum & Stages

In the 2nd

NPC meeting held on 16.07.2013 at Delhi, four (4) stages under frequency relay operation

starting from 49.2 has been approved. The methodology to arrive at quantum of load relief as espoused

in Zalte committee report has been approved and load relief for each region was arrived. The calculated

apportion of quantum of load shed w.r.t. WR is as follows.

Frequency (Hz) WR (MW) Required Load relief in NEW Grid (MW)

49.2 2060 5143

49.0 2070 5175

48.8 2080 5207

48.6 2100 5239

Stage wise desired load shed (Assuming power number as 3000 MW/Hz w.r.t. NEW grid)

WRPC proposed following method of distribution among its constituents. (i) Considered max catered

demand of each state (utility) in previous year (April, 2012 to March, 2013).

(ii) Calculated the percentage of each state w.r.t. to total

(iii) The amount of load shed is calculated on these percentages w.r.t. WR load shed.

State Gujarat MP CG Maharastra Goa DD DNH Total

Catered Demand (Max) 11960 9462 3134 16665 475 279 669 42644

% of Total 28.0 22.2 7.3 39.1 1.1 0.7 1.6 100

Max Catered Demand of states of WR

The calculation of quantum of load shed w.r.t. states is as per Zalte Committee report/recommendations.

Frequency

(Hz)

(In MW)

WR Gujarat MP CG Maharastra Goa DD DNH

49.2 2060 580 460 150 805 25 10 30

49.0 2070 580 460 150 810 25 15 30

48.8 2080 580 460 155 815 25 15 35

48.6 2100 590 465 155 820 25 15 35

State wise desired load shed (figures were rounded off)

Constituents have already agreed to the above.

Constituents informed that in the existing AUFLS, single UFR is installed at the S/S for

implementing the load shedding under the three stages. It needs to be ascertained whether the

existing UFRs support the four stage load shedding or not. It was informed that if the existing

UFR supports the four stage frequency setting then the above could be implemented within a

short span of time. If the existing UFRs do not support four stages of frequency setting, then new

UFR relays would have to be procured and this would take time.


It was suggested that if the existing UFRs do not support four stages of frequency settings, then

the first three stages i.e. 49.2, 49.0 and 48.8Hz shall be implemented with the existing relays, since

there is a rare chance of frequency touching 48.6Hz stage.

Committee felt that Constituents shall submit details/data of existing UFRs.

Further Constituents have to identify feeders and suitable amount load to be shed for each stage,

as above.

Further it was felt that if the existing UFR relay supports the four stage frequency settings, the

above Load Shedding quantum should be taken up for implementation.

As regards to testing/checking the status of UFR Committee felt that Constituents themselves

would give the certification on status of UFR by testing/checking the UFR. WRPC would carry out

inspection of UFR of some of the locations as mandated by IEGC but prime responsibility lies

with utility to maintain healthiness of relay.

CE SLDC GETCO informed that they would give the list of feeders for load shed w.r.t. these

stages, within 15 days.

Committee expressed that the states should initiate the process for procurement of the UFRs and

implement the above revised settings/recommendations within 3 months. MS, WRPC stated that

first two stages of UFR need to be implemented immediately but it requires coordination with

NEW grid. Therefore it will be requested to NPC to suggest a time slot in which whole NEW grid

would adopt new settings.

2. Over voltage protection

27 bus reactors were proposed to install in WR to maintain the voltage within permissible limits in

response to 33rd

& 34th

Standing committee report.

Accordingly the information regarding the commissioning schedule is as below:

S. No. 400 kV Sub/stn. Size (MVAR) Implementing

agency

Expected

Commissioning date

1 Jabalpur 125 PGCIL June 2014

2 Khandwa 125 PGCIL June 2014

3 Shujalpur 125 PGCIL June 2014

4 Bhatapara 125 PGCIL June 2014

5 Raigarh 125 PGCIL June 2014

6 Aurangabad 125 PGCIL June 2014

7 Ranchodpura 125 GETCO July 2013

8 Varsana 125 GETCO July 2013

9 Rajkot 125 GETCO July 2013


10 Amreli 125 GETCO 12th July 2013

11 Nanded 125 MSETCL 2014

12 Sholapur 125 MSETCL 2014

13 Kolhapur 125 MSETCL 2014

14 Akola 125 MSETCL 2014

15 Jetpur 63 GETCO 11th July 2013

16 Zerda 125 GETCO July 2013

17 Limbdi (Chornia) 125 GETCO July 2013

18 Nagda 125 MPPTCL September 2014

19 Bhopal 80 MPPTCL March 2014

20 Damoh 125 PGCIL August 2014

21 Bachau 125 PGCIL August 2014

22 Pirana 125 PGCIL August 2014

23 Itarsi 2X125 PGCIL August 2014

24 Seoni 125 PGCIL August 2014

25 Parli 125 PGCIL August 2014

26 Raipur 125 PGCIL August 2014

27 Gwalior 125 PGCIL August 2014

The respective utilities were requested to install/commission as per above schedule.

It has been discussed and decided in 23rd

WRPC meeting and subsequently in 448th

OCC meeting that

the priority of reactor installation is as follows.

Priority of reactors to be installed

S.

No..

400 kV Sub

Station MVARs

Implementing

Agency Status

Reactor

priority

Reactor priority

within State

1 Raigarh 125 PGCIL

Orders placed and

commissioning from Jan 14

to June 14

I I (Chhatisgarh)

2 Sholapur 125 MSETCL 2014 II II (Maharashtra)

3 Kolhapur 125 MSETCL 2014 II II (Maharashtra)

4 Damoh 125 PGCIL Aug-14 III II (Madhya Pradesh)

5 Seoni 125 PGCIL Aug-14 III I (Madhya Pradesh)

6 Raipur 125 PGCIL Aug-14 IV II (Chhatisgarh)

7 Gwalior 125 PGCIL Aug-14 V III (Madhya Pradesh)

8 Aurangabad 125 MSETCL

Orders placed and


to June 14

VI I (Maharashtra)

9 Akola 125 MSETCL 2014 VII III (Maharashtra)

10 Versana 125 GETCO Orders placed and

commissioning by June 13 VIII I(Gujarat)

11 Amreli 125 GETCO Orders placed and

commissioning by June 13 VIII I (Gujarat)


12 Rajkot 125 GETCO Orders placed and

commissioning by June 13 VIII I (Gujarat)

13 Ranchodpur

a 125 GETCO

Orders placed and

commissioning by June 13 IX II (Gujarat)

14 Shujalpur 125 MPPTCL

Orders placed and


to June 14

X III (Madhya Pradesh)

15 Nagda 125 MPPTCL Sep-14 XI IV (Madhya Pradesh)

16 Khandwa 125 PGCIL Orders placed and


to June 14

XII V (Madhya Pradesh)

17 Zerda 125 GETCO Jul-13 XIII III (Gujarat)

18 Limbdi 125 GETCO Jul-13 XIII III (Gujarat)

19 Bhopal 80 MPPTCL Mar-14 XIII VI (Madhya Pradesh)

20 Bhatapara 125 PGCIL Orders placed and


to June 14

XIV II (Chhatisgarh)

21 Jabalpur 125 MPPTCL Orders placed and


to June 14

XV VIII (Madhya

Pradesh)

22 Itarsi 125 PGCIL Aug-14 XVI VII (Madhya

Pradesh) 23 Parli 125 PGCIL Aug-14 XVII IV (Maharashtra)

24 Bachau 125 PGCIL Aug-14 XVIII IV (Gujarat)

25 Pirana 125 PGCIL Aug-14 XIX V (Gujarat)

26 Jetpur 125 GETCO Jul-13 XX VI (Gujarat)

27 Nanded 125 MSETCL 2014 XXI V (Maharashtra)

RGPPL representative informed that when all units are out, high voltage is observed and the lines are

getting tripped on over voltage. Due to this RGPPL is not able to synchronize with grid also they are not

getting power for station necessaries such as H2 purging in case the blackout prevails for more than 2-

3hrs which leads to substantial restoration time for units. Further loss of supply beyond 2-3hrs can lead

to disastrous consequences such as flaring of gas to atmosphere is resorted.

Committee felt that since reactive power requirement planning of grid/state done by considering

all generators in service, it would not be appropriate to suggest that STU should plan for reactor

installation for such a condition. Further it was felt that the issue of all units out at a generating

station is specific to RGPPL, therefore RGPL may install suitable reactors by considering all units

under outage.

3. Zone – 3 philosophy

In the 2nd

NPC meeting held on 16.07.2013 it was decided that SLDC/STUs of WR have to submit

relevant data to CTU (PGCIL) of the lines which required coordination with PGCIL lines to implement

zone -3 settings on these.

Utilities agreed to submit the relevant data to CTU (PGCIL).


4. SPS for Gwalior - Agra

It was decided in a 22nd

WRPC meeting to implement SPS on Gwalior – Agra Line. In this regard i.e. if

both lines trip simultaneously, 1500 MW back down will be done in NR and 500 MW back down in

WR. This 500 MW back down with participation of following stations.

S No. Generating Station Capacity (MW)

1 CGPL 4000

2 KSTPS - NTPC 2600

3 Sipat- NTPC 2980

4 VTPS-NTPC 4260

5 Jaypee Bina 500

Subsequently in a meeting of NRPC, CTU informed that fiber optic communication

connection is not available at NTPC – Sipat. Further the capacity of Jaypee Bina is small.

Therefore till the arrangement of fiber optic communication connection is made available at

NTPC Sipat the apportionment of 500 MW generation back-down to remaining generating

stations would be as follows.

S No. Generating Station Desired Back Down (MW)

1 CGPL 180

2 KSTPS - NTPC 120

3 VTPS-NTPC 200

(Figures rounded off)

Representatives from above generating stations confirmed that they are ready to back down the

above quantum. Representative of respective generating station stated that CGPL requires 5-6

minutes, KSTPS-NTPC requires 8-10 minutes and VSTPS-NTPC requires 8-10 minutes to achieve

above quantum of backing down.

For implementation of the above scheme, Committee expressed that,

(i) PGCIL shall coordinate with KSTPS, VTPS & CGPL for providing the necessary potential

free hard contacts at these stations.

(ii) Tata telecom broad band line leasing will be explored by PGCIL for CGPL and would

provide hard contact at the station gantry. PGCIL shall provide fiber optic communication

channel up to the gantry of switchyard and potential free hard contacts. The exact location should

be intimated by PGCIL. PGCIL will check and give the implementation status of OPGW and has

to complete implementation of this SPS within 3 months period.


(iii) Beyond the gantry point necessary arrangements (i.e cabling and necessary backing down

signaling) shall be made by respective generator (i.e. CGPL, VSTPS, KSTPS and Sipat), and shall

start the process of procuring necessary hardware/software and other requirements for

implementing the backing down of the above quantum.

MS, WRPC stated that expediency of SPS on Bina – Gwalior – Agra entails that concern agencies of

WR responsible for effecting back-down of 500 MW in WR should endeavor to complete the job within

three months.

ITEM NO. 7: Any other Item.

7.1 Islanding schemes for Nuclear Power Stations:

Member Secretary WRPC informed that in the 2nd

NPC meeting held at New Delhi, the matter of

formulation of Islanding schemes for Nuclear Power Stations was discussed. The Islanding schemes for

TAPS 1&2, TAPS 3 & 4 and KAPS were discussed in the past and Islanding for KAPS was in place for

some time. Later, due to change in system configuration and non-availability of flexibility of generation

and load scheme was kept in abeyance.

It was decided that a small group would look in the formulation of Islanding schemes for TAPS

1&2, TAPS 3&4 and KAPS.

ITEM NO. 8: Date and Venue of the next meeting.

It was decided that the next PCM would be held in August 2013 and would be hosted by NPCIL at

TAPS 3 & 4, Tarapur.

Annexure - I

Sl.No. Organisation & Name Designation E-mail Mobile No. 1 Shri S.K. Negi M D GETCO2 Shri B.B. Mehta C E GETCO [email protected] 98792007363 Shri S.A. Patel E E GETCO [email protected] 99252110414 Shri K.G. Patel D E GETCO [email protected] 99252109775 Shri S.S. Rajurkar S E MSETCL/MSPGCL [email protected] 97695090206 Shri R.H. Satpute S E MSETCL/MSPGCL [email protected] 99301285357 Shri A.V. Deo S E MSETCL/MSPGCL [email protected] 91672764878 Shri S.P. Vasekar S E MSETCL/MSPGCL [email protected] 88888340129 Shri P.S. Kulkarni E E MSETCL/MSPGCL [email protected] 8408889906

10 Shri Sunil Yadav E E MPPGCL/MPPTCL [email protected] 942580491611 Shri Mohan Sahu E E MPPGCL/MPPTCL [email protected] 942580502712 Shri Sharad Shrivastava S E CSPTCL [email protected] 942554315713 Shri Anand Dubey C M POWERGRID [email protected] 942850406514 Shri Dilip Kasture Sr. Engr. POWERGRID [email protected] 942214533415 Shri D.R. Chowdhury A. G. M. NTPC [email protected] 942522209416 Shri R.K. Aash A. G. M. NTPC [email protected] 942940844917 Shri S. Paul A. G. M. NTPC [email protected] 900449713818 Shri Prasun Chkraborty A. G. M. NTPC [email protected] 942522225319 Shri M.M. Rai SO/F NPCIL [email protected] 942337722620 Shri K.N. Athavale G.M. Tata Power [email protected] 922729535821 Shri M.V. Kini D.G.M. Tata Power [email protected] 922332114022 Shri Alok Uppal C.M. Tata Power [email protected] 909900643023 Shri Girish Jawale Mgr. Tata Power [email protected] 922331141924 Shri Kamlesh Trivedi A.G.M. Torrent Power [email protected] 922724695025 Shri Abhishek Kumar Singh Asst. Mgr. VEDANTA [email protected] 998199591726 Shri Ayyaj Maner Mgr. Reliance Infra [email protected] 932436239927 Shri Rakesh Sharma Supdt. NSPCL [email protected] 942529332328 Shri Kundan Rathod Sr. Supdt. RGPPL [email protected] 942387717329 Shri K.Muralikrishna C M WRLDC [email protected] 986945021930 Ms. Pushpa Seshadri C M WRLDC [email protected] 986940448231 Shri Chandan Kumar E WRLDC [email protected] 986925146032 Shri S.D. Taksande M S WRPC [email protected] 982087838433 Shri Satyanarayan S. S E WRPC [email protected] 922339993834 Shri P.D.Lone E E WRPC [email protected] 986762282335 Shri L.K.S. Rathore E E WRPC [email protected] 983337184436 Shri D.N. Gawali E E WRPC [email protected] 993066676537 Shri Shiva Suman A D WRPC [email protected] 9869910968

LIST OF PARTICIPANTS OF 118th PCM MEETING HELD ON 19.07.2013 AT WRLDC, MUMBAI

Annexure 2.3.1

Clarification on occurrence of 400 KV S/s (MPPTCL) Bina on dt. 24.05.13 Included as agenda item no. 2.3.1 for the 118th PCM dated 19.07.13.

On 24.05.13, at 04:39 hrs, “ Y “ CT of 220 KV Bina Interconnector II got burst at 400 KV S/s

MPPTCL Bina end. The status and sequence of events were as following;

i. 220 KV Bina I/C II was on Main bus II. Bus Bar protection scheme was under commissioning

and Main bus I & II were connected through 220 KV Bus Tie.

ii. On the event of CT Failure, it caught fire and damaged the line side and auxiliary bus side

isolators and created a 220 KV bus fault.

iii. Due to bus fault the all the 220 KV feeders tripped from other ends in zone II, except 220 KV

Guna II, 220 KV Bus Tie tripped on E/F and also 220 KV incomers of 315 MVA Transformer

I & III tripped on Definite time delay O/C protection as following;

Sr. No.

Name of Feeders / Transformer

Indication at 400 KV S/S Bina

Indication at other S/S

Remarks

1 220 KV IC II Zone I B Ph (Of ABC )

A & C Ph Zone II

At first only B (Y) phase pole of CB at 400 KV S/s Bina end tripped, on single phase tripping, other two poles tripped on three phase tripping.

2 220 KV Gwalior II Zone IV A,B,C Ph

B-N Ph Zone II

3 220 KV Sagar II No Tripping/ No Ind.

L1,L2,L3 Zone II

4 220 KV PGCIL No Tripping/ No Ind.

R,Y,B Ph Zone II

5 220 KV Guna II Not Tripped Not Tripped 6 220 KV Bus Tie E/F , 86 T 7 220 KV IC I No Tripping/

No Ind. CN Zone I

8 220 KV Gwalior I No Tripping/ No Ind.

BN Zone II

9 220 KV Sagar I No Tripping/ No Ind.

L1,L2,L3 Zone II

10 220 KV Guna I No Tripping/ No Ind.

CN Zone II

11 220 KV Shivpuri No Tripping/ No Ind.

12 315 MVA Transformer II Incoming

DTOC II


Not Tripped


DTOC II

iv. Initially Y phase CB pole of 220 KV IC II tripped at 400 KV S/s end, isolated the fault,

same was isolated from other ends in Zone II time. But due to fire and flames and charged status

of other two poles, high resistive arcing persisted which were cleared in 926 msec with

tripping of other two poles of 220 KV IC II CB. A copy of DR of 220 KV IC II enclosed

herewith displaying, 926 msec as the overall duration of wave form distortion on 220 KV bus at

400 KV S/s Bina. PT supply displaying is available through the 220 KV Bus PT, live through

the 220 KV Guna II and 220 KV incomer of 315 MVA Transformer II at 400 KV S/s Bina.

v. It is therefore, the overall disturbances at 400 KV S/s (MPPTCL) Bina cleared in 926

msec.

Remedial Action:

On dt. 27.05.13, 220 KV Bus Bar Protection Scheme (GE make 90) commissioned at 400

KV S/s Bina. It was under commissioning stage during above occurrence.

Baart sark ar Government of India d`Iya ivaVut … received from MPPTCL is enclosed at Annex.-2.3.1...

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Transcript of Baart sark ar Government of India d`Iya ivaVut … received from MPPTCL is enclosed at Annex.-2.3.1...