Baart sark ar Government of India d`Iya ivaVut … received from MPPTCL is enclosed at Annex.-2.3.1...
Transcript of Baart sark ar Government of India d`Iya ivaVut … received from MPPTCL is enclosed at Annex.-2.3.1...
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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
2 Minutes of 118th Protection Committee of WRPC
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.
3 Minutes of 118th Protection Committee of WRPC
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.
4 Minutes of 118th Protection Committee of WRPC
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.
5 Minutes of 118th Protection Committee of WRPC
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.
6 Minutes of 118th Protection Committee of WRPC
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.
7 Minutes of 118th Protection Committee of WRPC
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
8 Minutes of 118th Protection Committee of WRPC
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.
9 Minutes of 118th Protection Committee of WRPC
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.
10 Minutes of 118th Protection Committee of WRPC
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.
11 Minutes of 118th Protection Committee of WRPC
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.
12 Minutes of 118th Protection Committee of WRPC
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.
13 Minutes of 118th Protection Committee of WRPC
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.
14 Minutes of 118th Protection Committee of WRPC
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.
15 Minutes of 118th Protection Committee of WRPC
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.
16 Minutes of 118th Protection Committee of WRPC
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.
17 Minutes of 118th Protection Committee of WRPC
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.
18 Minutes of 118th Protection Committee of WRPC
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.
19 Minutes of 118th Protection Committee of WRPC
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.
20 Minutes of 118th Protection Committee of WRPC
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
21 Minutes of 118th Protection Committee of WRPC
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
commissioning from Jan 14
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)
22 Minutes of 118th Protection Committee of WRPC
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
commissioning from Jan 14
to June 14
X III (Madhya Pradesh)
15 Nagda 125 MPPTCL Sep-14 XI IV (Madhya Pradesh)
16 Khandwa 125 PGCIL Orders placed and
commissioning from Jan 14
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
commissioning from Jan 14
to June 14
XIV II (Chhatisgarh)
21 Jabalpur 125 MPPTCL Orders placed and
commissioning from Jan 14
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).
23 Minutes of 118th Protection Committee of WRPC
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.
24 Minutes of 118th Protection Committee of WRPC
(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
13 315 MVA Transformer II Incoming
Not Tripped
14 315 MVA Transformer II Incoming
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.