Southern Regional Power Committee - Govt of India, Ministry of … · 2018-09-28 · 765 Kv Anta - Phagi- II 40 -46 -215% 1088 276 25% 1127 229 20% 23.05 ... NTPC informed that at

RGMO/MVAR Meeting – 26.09.2018 Page 1

Minutes of the RGMO/MVAR Meeting held on 26.09.2018 at SRPC, Bengaluru

1. Introduction

A Meeting on RGMO/MVAR was held at SRPC, Bengaluru on 26th September 2018.

The list of Participants is given at Annexure-I.

It was noted with concern that there was no representation from APSLDC, TNSLDC

(had informed that they would not be attending the meeting), NTPC-Talcher, MAPS,

KGS, KKNPP, JSWEL, IL&FS & HNPCL.

Shri S R Bhat, Member Secretary, SRPC welcomed all the participants and noted that

the 9th

meeting on RGMO/MVAR was being held after a gap of around one & half years

since 8th

meeting was held in April 2017. Around 10 incidents since April 2017 of

RGMO were to be analysed during the course of this meeting. Role of generators in

voltage management was also essential to maintain the voltage profile within the

permissible limits, with reactive interchange within the capability curves. From 1st April

2017 to 31st August 2018, the MVAR analysis would be discussed so as to identify steps

to improve the performance.

2. RGMO/FGMO WITH MI

Hydro Thermal TOTAL

Possible

(MW)

Actual

(MW) %

Possible

(MW)

Actual

(MW) %

Possible

(MW)

Actual

(MW) %

26.04.2017 (10:01 hrs) frequency rose from 50.02 Hz to 50.21 Hz (+0.19 Hz) -

Tripping of Karad & Kolhapur ICT's occurred, resulting Load loss of 900 MW

-78 -18 23% -965 -307 32% -1043 -325 31%

09.05.2017 (16:41 hrs) frequency fell from 49.99 Hz to 49.86 Hz (-0.13 Hz) – 400 kV

J.P.Nigri-Satna line - 1&2 tripped at 16:19 and 16:41 Hrs due to which Unit- 1&2 at

J.P.Nigri tripped due to loss of evacuation lines. Generation Loss of 1180 MW

32 15 47% 1041 250 24% 1073 265 25%

18.05.2017 (08:01 hrs) frequency fell from 50.10 Hz to 49.83 Hz (-0.27 Hz) - Rihand

TPS Unit 1, 2 & 4 tripped and at 08:03 Hrs Rihand TPS Unit 3, 5 & 6 got tripped.

Generation Loss around 2750 MW.

39 114 292% 1021 333 33% 1060 447 42%

20.05.2017 (20:06 hrs) frequency fell from 50.08 Hz to 49.86 Hz (-0.22 Hz) -2000

MW generation loss at Chavra/Anta generation complex at Rajasthan due to fault at

765 Kv Anta - Phagi- II

40 -46 -

215% 1088 276 25% 1127 229 20%

23.05.2017 (17:43 hrs) frequency fell from 49.93 Hz to 49.72 Hz (-0.21 Hz) -

Vindhyachal Stage-III tripped reportedly due to fire in Generator Transformer.

Vindhyachal Unit 8, 9 & 10(capacity 500 MW each) tripped.

24 28 117% 1127 266 24% 1151 294 26%

16.08.2017 (12:18 hrs) frequency fell from 49.93 Hz to 49.84 Hz (-0.09 Hz) - 979 MW

Generation loss at Teesta and Dikchu due to 400kV Rangpo-Teesta


44 45 104% 939 235 25% 983 280 29%


Generation loss of 1097 MW due evacuation lines tripping of Taleandi Sabo

64 2 3% 1091 340 31% 1155 342 30%

09.12.2017 (12:58 hrs) frequency rose from 50.04 Hz to 50.16 Hz (+0.12 Hz) – 1400

MW Load loss Padghe S/S TBC blast, all feeders tripped

-74 -48 65% 894 342 38% 968 390 40%


Generation of loss of 1250 MW at Koderma and Load loss of 300 MW

41 53 130% 669 159 24% 710 211 30%

23.04.2018 (10:42 hrs) frequency fell from 50.02 Hz to 49.71 Hz (-0.31 Hz) - 3090

MW generation loss at DB Power, KSK, SKS, RKM, TRN and NSPCL generating

stations

81 109 135% 1282 380 30% 1363 489 36%

Deliberations

The incident of 30.01.2018 was agreed to not to be considered for RGMO/FGMO

with MI analysis since fall in frequency was only 0.07 Hz (reportedly in steps).

MS, SRPC emphasised the importance of RGMO / FGMO with MI and reminded

that ED, SRLDC in the AGC meeting held on 19.09.2018 had stated that non-

implementation of primary response, AGC and grid requirements for RE

(including LVRT) was a certain recipe for grid disturbance and all the stake

holders needed to take definite action in this regard.

Krishnapattnam (APGENCO-JV) informed that they had modified the logic in

July 2018 and the performance would be monitored.

NLC informed that they constituted an internal team to review the RGMO

performance and the performance would be reviewed.

NTPL informed that the RGMO logic was modified in December 2017 and the

performance was under review.

Ramagundam, NTPC informed that Unit-I, II & III controllers along with turbines

were planned to be replaced during 2019-20 and then the response can be

expected.

Simhadri, NTPC informed that the logic of disabling the RGMO at technical

minimum has been disabled from April 2018 for Stage-II and August 2018 for

Stage-I.

It was noted that the response of Talcher Stage-II was poor and there was no

representation by Talcher Stage-II.NTPC, SRHQ was requested to kindly take up

the issue with Talcher Stage-II.

SEIL informed that TPCIL units RGMO logic has been modified during 1st week

of November 2017 and for SGPL units in June 2018. The performance was under

review.

It was noted NTECL had put an alarm during triggering of RGMO requirement

and during such incidents; the operators suspend the normal scheduling


requirements for few minutes. The generators were requested to consider the

option if found feasible.

KPCL informed that BTPS Unit-I & II RGMO logic has been modified during

December 2017. Unit-III logic modification would be carried out during the

shutdown (which is undergoing).

KPCL informed that the RGMO had some issue at Raichur Unit-IV, the

rectification would be considered during major overhaul.

UPCL informed that they had implemented the same logic deployed at Tiroda and

fine tuning was being carried out. As recommended in the 8th

meeting, the dead

band was removed soon after that meeting.

TANGEDCO informed that the DCS was to be replaced for Unit-I & II at Mettur.

PO would be placed and by December 2018, the commissioning was expected. In

some instances of rise in frequency since the machines were on FGMO with MI,

the operator had given a command on the alarm for increasing the generation.

TANGEDCO informed that at Mettur stage-III, the logic had been modified in

July 2018 and the response would be monitored. TANGEDCO confirmed that the

dead band in the operating frequency range had been disabled.

TANGEDCO informed that for NCTPS stage-I Unit-I the PO for DCS would be

placed within a week and it would take 2-3 months to complete the work. The

logic would be implemented and response would be monitored.

TANGEDCO informed that for NCTPS stage-II the revised logic had been

implemented from 04.10.2018 and the performance was under review.

TANGEDCO was requested to assess the settings of RGMO at Tuticorin

(Hydraulic Governor) as there was no response during rise in frequency incidents.

TSTRANSCO informed that Singareni Unit-I, the revised RGMO logic had been

implemented from June 2018 and the response would be monitored.

KPCL informed that at load less than 50%, the RGMO was disabled.

It was pointed out that the RGMO/FGMO with MI was to be in place at all

loadings.

NTPC informed that at Kudgi Unit-I & II, the revised logic had been implemented

two months back and fine tuning was being undertaken.

KPCL agreed to look into the non-response at Kadra. The data recording facility

at Nagjheri was being undertaken. At Supa, the RGMO / FGMO with MI was not

possible due to head and balancing reservoir (for Nagjheri) constraints. It was

pointed out that the exemption can be sought from Hon’ble Commission until that

time, the performance would be measured.

KSEBL informed that logic at Idukki Units-I to III would be modified and tuned

after the R&M.

Summary / Recommendations

The generators pointed out that in some cases; there was discrepancy in the output at

the generator vs the results in the report. The observations with actual performance

had been communicated to the SLDCs but had not reflected in the report.


SRLDC & SRPC pointed out that the analysis was being discussed in the respective

OCC meetings and any anomaly needed to be rectified at that time. The state

generators needed to coordinate with the SLDCs to address the mismatch between

the SCADA and the response at the generator terminals.

In view of the above, it was agreed that the spreadsheet with the response would

be communicated by SRLDC (by 28.09.2018) and the state generators needed to

interact with the SLDCs to ensure that the response observed at the generator

terminal is reflected in the reports after thorough validation by the SLDCs by

05.10.2018.

The unit-wise / station-wise response / analysis would be communicated after

incorporating the comments / feedback.

In Petition No. 302/MP/2013 ( Date of Order : 23.10.2015), Hon’ble CERC had

directed in the Order, ‘However, SLDCs are not reporting the performance of the

generators on regular basis. Accordingly, SLDCs/RLDCs are directed to keep watch

on the response of generators during major frequency excursions and submit report

on quarterly basis to SERCs and POSOCO. SLDCs, through their respective

SERCs, may also initiate action against defaulting State`s generators in

accordance with the provisions of the Grid Code.’

In Petition No. 84/MP/2015 (Date of Order: 31.07.2017) Hon’ble CERC had directed

the following :

‘(a) Considering the fact that further measures have been put in place to facilitate

desirable primary response, the Commission, starting from the month of

September, 2017 shall be closely watching the primary response of ISGSs as

reported by POSOCO/NLDCs. At the State level, SLDCs shall report the

frequency response of intra-State generators to the concerned SERCs.

(b) NLDCs and SLDCs through the assistance of POSOCO shall start the process

of selecting independent third parties capable of undertaking periodic checkups to

monitor the RGMO/FGMO response. To start with selected independent third

parties shall be sent to the generating stations which are not providing the desired

RGMO/FGMO response. Independent Third Parties shall ensure that the

generator has not, in any way, prevented/disabled the governor from providing

the desired response. In case, even after enabling the governors, units are not able

to provide the desired response as per the provisions of the Grid Code, third

parties, based on the submissions of the generators, shall bring out the technical

constraints, if any, which limit the primary response of the units.

c). All ISGSs are directed to provide primary response compulsorily in terms of

Regulation 5.2 (f), (g), (h) and (i) of the Grid Code failing which we would not

hesitate in initiating action under Section 142 of Electricity Act, 2003 for not

providing desired RGMO/FGMO response without any valid reasons’.

It was noted that number of units were not giving desired performance in number of

incidents. It was also felt that adequate monitoring / follow-up was not being carried

out by SLDCs for the non-performance of the units. The generators needed to

interact with the SLDCs for non-performance on the applicable incidents (generators

sought one month time to complete the activity). Therefore, it was agreed that a

VC held with the SLDCs (one at a time) after one month with participation by


SRLDC& SRPC to review the performance. Inadequate response was needed to

be taken up by SLDCs with respective SERC’s in line with Hon’ble CERC

Orders in respect of Petition No. 84/MP/2015 and 302/MP/2013.

The non-performance of the generators under SRLDC control would be taken

up by SRLDC with the respective generators.

Logic implemented at few generators where RGMO response is satisfactory is

enclosed at Annexure-II (SRLDC letter dated 12.06.2017). All the Generators to

note that this was only for understanding but each generator had to ensure RGMO

compliance as per IEGC and as per their machines make, vintage, DCS etc.

It was noted that some of the generators were disabling RGMO without informing /

concurrence from SLDC/SRLDC. The IEGC provision states ‘5.2(f)(ii)(c) if any of

the generating units is required to be operated without its governor in operation as

specified above, the RLDC shall be immediately advised about the reason and

duration of such operation.’ The IEGC provision needed to be complied.

The following Regulation had been added in the 5th

Amendment to IEGC

‘For the purpose of ensuring primary response, RLDCs/SLDCs shall not schedule

the generating station or unit(s) thereof beyond exbus generation corresponding to

100% of the Installed capacity of the generating station or unit(s) thereof. The

generating station shall not resort to Valve Wide Open (VWO) operation of units

whether running on full load or part load, and shall ensure that there is margin

available for providing Governor action as primary response. In case of gas/liquid

fuel based units, suitable adjustment in Installed Capacity should be made by

RLDCs/SLDCs for scheduling in due consideration of prevailing ambient conditions

of temperature and pressure vis-à-vis site ambient conditions on which installed

capacity of the generating station or unit(s) thereof have been specified’.

SLDCs were suggested to ensure that the schedules are restricted to normative exbus

generation. The generators were suggested not to resort to VWO and maintain

generation as per the coal quality/ system/machine parameters and keep the margins

for RGMO / FGMO with MI at all instances.

SRLDC informed that any incident from now would be analysed in detail and if there

was no significant improvement, they may be constrained to approach Hon’ble

CERC through petition.

It was suggested that wherever FGMO with MI is implemented, a discernible alarm

for rise in frequency / fall in frequency needs to be implemented to avoid such

adverse operations.

RGMO status points to be configured to SLDC / SRLDC SCADA would be discussed

in the VC with individual states.

As there was no representation by some of the SLDCs, it was noted that the FRC

computation would be discussed in the VC with individual states.

As per 5th

Amendment to IEGC, gas stations above 50 MW Installed Capacity were

also to come under RGMO/FGMO operation w.e.f. 1st October 2017. Status update

in this regard would be discussed in the VC with individual states.


The need for testing of RGMO response at the field emerged as the response was not

forthcoming. In this regard, para under Regulation 5.2(h) as per 5th

Amendment of

IEGC was noted, ‘Provided that periodic checkups by third party should be

conducted at regular interval once in two years through independent agencies

selected by RLDCs or SLDCs as the case may be. The cost of such tests shall be

recovered by the RLDCs or SLDCs from the Generators. If deemed necessary by

RLDCs/SLDCs, the test may be conducted more than once in two years’.

SRLDC stated that they would revert back on this after discussing with NLDC.

SLDCs are requested to ensure compliance of the above Regulation.

3. MVAR Issues

The data for MVAR interchange was sought for the period from April 2017 to August

2018.

Stations not submitted the data:

APGENCO: VTPS, RYTPS, U_Sileru & L_Sileru

TS: Singareni

KAR: YTPS (KPCL), UPCL

TANGEDCO: MTPS-III, NCTPS & Kadamparai

NPCIL: KGS & MAPS

NTPC: RSTPS, Talcher-II & Kudgi

NLC: NLC-I, I Exp, II, II Exp

ISGS: SEL & SEIL

Station submitted data but not in format/consolidated: All stations data received

from KSEBL (for one month), NTPL, SDSTPS and all hydro data received from

KPCL

Station submitted consolidated data in format: Simhadri, NTECL, IL&FS, NTPL,

KKNPP, MEPL, JSWEL, BTPS, TTPS, MTPS1, HNPCL, COASTAL, SGPL,

KTPP, N’SAGAR, SSLM LB, SSLM RB

SRLDC made a presentation on MVAR interchange (Annexure-III) for the

period from April 2017 to August 2018.

MVAR Inter-change analysis:

AP

Station Unit No. Comments/Remarks

HNPCL

Station Both the units injecting at the voltages below

410 kV and absorbing up to 170 MVAR above

410 kV

SSLM RB Station All the units were absorbing as per capability

TS


KTPP Station Data not submitted in proper format


KTPS Station Data submitted partially

N’SAGAR Station

All the units absorbing up to 20-30 MVAR

over 215 kV-235 kV range. Tap position data

not given.

SSLM LB

Station All the units were absorbing as per capability.

And, absorbing around 60-70 MVAR in

condenser mode

Karnataka


BTPS-KPCL Station Both the units injecting at the voltages below

405 kV and absorbing upto120 MVAR above

405 kV

JSWEL Station All the units were found to be absorbing upto

75 MVAR and injecting up to 100 MVAR

Kerala


All hydro (>50 MW) Station Only one month data submitted

Tamil Nadu


TTPS-TANGEDCO Station Injecting at the voltages below 237 kV. All the

units were found to be absorbing upto 30-50

MVAR

MTPS1-TANGEDCO Station All the units were injecting as per requirement

and found satisfactory

NPCIL


KKNPP Station

Both the units were found to be absorbing up

to 170-190 MVAR, and injecting upto 300

MVAR

NLC/NTPL


NTPL Station

Unit1: Found to be absorbing upto 150

MVAR

Unit2:Data not submitted properly

NTPC/NTECL


Simhadri Station All the units were found to be satisfactory.

NTECL Station All units were found to be injecting when

voltages were less than 400 kV. Units were

injecting/absorbing up to 180 MVAR between


400-410 kV. Above 410 kV, units are

absorbing and were found to be satisfactory.

IPPs


COASTAL

1

Absorbing up to 130 MVAR (Capability

around 200 MVAR) above 410 kV. Desired

absorption above 400 kV.

2 Absorbing up to 120 MVAR (capability

around 200 MVAR) above 410 kV. Desired

absorption above 400 kV.

IL&FS Station

Both the units absorbing upto 110-125 MVAR

(Capability around 170 MVAR) above 405

kV. Desired absorption above 400 kV.

MEPL Station Both the units were found to be absorbing as

per the agreed quantum.

SGPL Station

Both the units were found to be absorbing

130-140 MVAR, (Capability around 170

MVAR@ 600 MW, 280 MVAR @ 500 MW)

Seems limiter at 140 MVAR, more MVAR can

be absorbed at lower MW Generation.

Summary / Recommendations

It was noted that many of the stations had not furnished the MVAR interchange

details and therefore, a comprehensive exercise could not be carried out. Therefore, it

was agreed that SRLDC would communicate the format (along with the guidelines to

fill the format). The data for the period from April 2018 to September 2018 needs

to be furnished. The SRLDC controlled stations response would be analysed in

the OCC meeting. The state embedded generators need to furnish their

response to the SLDCs (with a copy to SRLDC/SRPC) and unit-wise / station-

wise analysis would be carried out after through VC with individual SLDCs

(after the RGMO VCs).

It was noted that there were still some margins available as per Capability Curve

and generators could consider improving the MVAR interchange.

It was noted that few units were not keeping the Vref to nominal and were changing it

manually to control / restrict the MVAR interchange. This was to be discontinued.

SLDCs would discuss the MVAR issues for embedded generators along with

RGMO/FGMO issues.

SRLDC would take up the status point availability to SRLDC of the GT taps for ISG

stations, wherever not extended.


4. Conclusion

Member Secretary, SRPC thanked the participants for their active inputs and valued

contributions and hoped that the generators would take steps to improve the

RGMO/MVAR performance.

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Documents

Southern Regional Power Committee - Govt of India, Ministry of … · 2018-09-28 · 765 Kv Anta - Phagi- II 40 -46 -215% 1088 276 25% 1127 229 20% 23.05 ... NTPC informed that at