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Southern Regional Power Committee (SRPC) Bangalore

Minutes of the 70th meeting of the Operation Coordination Sub-Committee

of SRPC held at Bangalore on 9th April, 2012

1. INTRODUCTION

1.1 The 70th meeting of the Operation Coordination Committee was held at Bangalore

on 9th April 2012. The list of Participants is given at Annexure - I. Due to

administrative reasons; Puducherry informed that they could not depute any officer

to attend the meeting.

1.2 Shri S.R.Bhat, Member Secretary i/c, SRPC welcomed the Members & other

participants to the 70th OCC Meeting. He informed that since Shri Biswarup Basu,

AGM (O&M), Talcher STPS, NTPC had been transferred to another plant, Shri D.

Kar, DGM (EEMG) would be representing Talcher II in OCC forum. MS i/c placed on

record the appreciation of Shri Biswarup Basu, AGM (O&M) for his active

contribution to the OCC forum. He along with forum members welcomed Shri D.

Kar, DGM and solicited his active participation/contribution in the Meetings.

1.3 MS i/c hoped that the Special Meeting on MVAR absorption scheduled to be held

after conclusion of the OCC Meeting would help resolve some of the issues

regarding persistent high voltage situation at nodes such as Vemagiri and

Vijayawada.

1.4 MS i/c informed that Palakkad 400 KV S/S with 315 MVA ICT had been

commissioned and put into commercial operation. He said that Palakkad S/S has

helped by relieving some of the load on the Thrissur ICTs thus aiding KSEB.

1.5 MS i/c appreciated the cooperation extended by KPTCL during the successful shut

down of 400 KV Nelamangala – Somanahalli lines (1 and 2) on 18th and 24th of

March 2012 for the purpose of commissioning of the 400 KV Bidadi substation. 230

KV Kalpakkam- Arni line had also been commissioned. It was also noted that two

bus reactors in NLC had also come into operation during the month. He pointed out

that there was a disturbance in Guttur 400 kV substation & Kali complex on 3rd April,

leading to formation of an island there. Karnataka and Andhra Pradesh had received

nil type ‘C’ messages during March ’12. Tamil Nadu and Kerala had obtained two

and one type ‘C’ messages respectively for over drawal at low frequency during

Minutes of the 70th

OCC Meeting of SRPC held on 09.04.2012

2

March ‘12. He appreciated KPTCL’s continuing record of nil grid violation messages

and again complimented Chief Engineer (LD) on this achievement. He sought the

cooperation of the constituents for avoiding over drawal at low frequency.

1.6 MS i/c said that the frequency had been in the IEGC range for 91.75% of time during

the month of March ‘12. The maximum frequency touched was 50.79 Hz on 08-03-

2012 around 1808 hrs. He informed the Members that as decided in the earlier

meeting, the trial load staggering exercise had been carried out by Andhra Pradesh

on 13th March-2012 and data pertaining to this exercise had been received. Due to

certain constraints on 12th March-2012, the load staggering exercise could not be

carried out by AP on that day. During the course of the meeting, SRLDC could

inform the forum about its observations in this regard.

1.7 MS i/c mentioned that with advancement of summer, the instances of over-drawal at

low frequency had been on the rise. During the month of March 2012, the load

shedding in TN was to the tune of 1880 MU, AP was at 1313 MU while Karnataka

was at 875 MU. There were also instances of sustained overdrawal by Kerala during

the first week of April-2012. He added that TN’s peak demand had come down as

compared to last year due to enforcement of high quantum of load shedding. He

said that as part of the Annual Exercise, the quantum of U/F relays needed to be

reviewed. He also informed that in the recently held meeting of the Protection Sub

Committee, the settings of df/dt relays in the region had been reviewed and

accepted. Further, based on the energy consumption & also peak demand for the

year 2011-12, the ‘Power Number’ for the year 2012-13 had also been calculated

and circulated.

1.8 MS i/c along with other Members of OCC congratulated PGCIL for bagging

prestigious Silver shield as part of the National Meritorious Performance Awards

instituted by Ministry of Power, Govt. of India for 2010-11. Further Ramagundam

STPC (PLF 93.1 %) and Simhadri (PLF 92.3 %) stations of NTPC were among the

best performing stations in the country during 2011 – 12. Mettur TPS (92.8%), Dr N

Tata Rao (91.6 %), Rayalseema (88 %), Tuticorin (85.6 %) and North Chennai (84.8

%) had also performed well during 2011 -12. The NTPC thermal stations had

performed well and could achieve the annual MoP Generation Targets (except

Talcher). NTPC deserved special appreciation in this regard since they had met the

MOP generation targets despite various constraints such as Telengana agitation,

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coal shortage issues, derailment of railway wagons etc. The availability of

Ramagundam St III, NLC TS I Expn and Simhadri II units during March 2012 was

more than 100 %, which deserved appreciation. The hydro storage position in the

hydro reservoirs was about 600 MU less than the position same time last year,

which was a matter of some concern

1.9 MS i/c requested Shri A. Balan, Superintending Engineer to take up the Agenda

Points of the meeting and accordingly the same were taken up for discussion.

2. CONFIRMATION OF THE MINUTES OF THE 69TH MEETING OF OCC OF SRPC HELD ON 8th March 2012

The Minutes of the 69th OCC Meeting were confirmed, with the following

amendments:

a) Last line of item 3.5.2 shall read as “In case this SPS scheme is not implemented by 15h April 2012 as decided in this OCC forum, then Hon’ble CERC may have to be approached.”

b) In last paragraph of item 5.1, Augmented capacity of 220/132/33 kV SS Garividi of AP shall read as ‘1x160 + 2x100’ instead of ‘1x60+2x100’.

3. MAJOR ISSUES

3.1 Shutdown of Talcher units

3.1.1 The following had been noted in the earlier Meetings:

a) AGM, Talcher, NTPC had informed that OSPCB was monitoring the situation at

Talcher, NTPC was carrying out the activities as per schedule. The

representatives of OSPCB were also regularly visiting the site. As informed

earlier, the clearance to operate the units was however likely to be received for

only three months at a time. OSPCB had accorded permission to operate

Talcher Stage-II units till 31st March 2012.

b) In the 69th OCC meeting, NTPC had informed that the coal supply had improved

to some extent. NTPC could maintain high level DC and availability of the

Talcher II units during February 12. It was noted that the monthly availability for

Talcher II for February 12 was 100.66 % which was appreciated by the forum.

NTPC had further informed that they were likely to get the extension for

operating the plants beyond 31st March 2012 from OSPCB.

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3.1.2 In the meeting, NTPC informed that during the last week of March-2012, an

OSPCB team had visited the Talcher plant and was satisfied with the compliance

measures. NTPC thus hoped that the plant would obtain necessary extension

shortly. During deliberations on this issue, it was again noted that less DC was

being declared in real time compared to day ahead DC thus leading to blocking

of the margin available in the corridor. SRLDC contended that in view of varying

DC declaration by NTPC, they were not in a position to accurately predict the

margin availability for STOA transactions. NTPC said that though they had been

furnishing realistic DC, at times on account of usage of coal from three different

sources and blending with foreign coal, it was extremely difficult to predict the

quality of coal in advance and give matching DC. MS i/c recalled that a meeting

in this regard with NTPC officials had already been held at Hyderabad. After

discussions, OCC suggested that NTPC may consider reduction of the DC so

that the corridor bandwidth could be fully utilized in view of the fact that the

states were reeling under huge power shortages and were eager to import more

power.

3.2 Tripping of HVDC Bhadravathi

3.2.1 The following was noted in the earlier Meetings:

a) The issue regarding tripping of HVDC Bhadravathi was deliberated in the 64th OCC Meeting. The issue had also been discussed in a Special Meeting held at Mumbai on 29th July 2011 with participation from Power Grid, WRLDC, SRLDC, WRPC & SRPC. It was noted that PGCIL had informed that the OEM (M/s ALSTHOM) had recommended that flow should not be more than 800 MW on a sustained basis. PGCIL had suggested the following immediate possibilities for reducing the power oscillations:

i) Power oscillation damping feature of HVDC Bhadravathi to be made on - Already taken in service, however further study was being carried out by PGCIL to fine tune its setting.

ii) PSS tuning at NTPC Ramagundam needs to be taken up.

The issue regarding implementation of measures/steps as finalized in the Special Meeting held at Mumbai on 29th July 2011 was taken up with WRTS-I & SRTS-I vide letter dated 12th September 2011. It was noted that any decision regarding restricting the flow upto 800 MW needed to be taken up by higher forum.

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b) In the 65th OCC Meeting PGCIL had informed that a letter dated 8th November 2011 had been addressed to SRPC giving point wise status of the issues pertaining to SRTS I, POWERGRID, which were discussed in the Special Meeting in Mumbai. This related to simultaneous measurement of harmonics and provision of web based video facility etc. MS I/c, SRPC had informed that in response SRPC had addressed a letter dated 9th November 2011 to POWERGRID. It was learnt that after discussions with M/s Areva, certain modifications in the settings had been suggested/carried out. He had therefore requested POWERGRID to furnish the status in this regard.

c) In the 69th OCC meeting, SRLDC had informed that they had sought high resolution data in respect of all the units of Ramagundam to analyse the hunting phenomenon when the power flow on HVDC Bhadrawathi is increased from 900 MW to 1000 MW. The data from NTPC was awaited. SRLDC also stated that before the proposed synchronization of NEW and SR grid by the year 2014, PSS tuning at Ramagundam must be in place. MS i/c had said that the outcome of the study carried out by M/s Areva as mentioned above could be informed to the forum. He requested that the concerned division at POWERGRID Corporate Centre could be apprised in this regard by SRTS – I.

3.2.2 In the meeting, SRLDC informed that they were in receipt of data from NTPC in

response to the discussions on this subject in the 69th OCC meeting. As inter-

regional control area oscillations were involved, the data needed to be sent to

other RLDCs for analysis. SRLDC further informed that it did not have the

necessary expertise for analysis of this data. It also suggested that the System

Study Sub Committee or Subject Experts could decode and interpret the data for

further progress.

3.3 SPS at Hosur


a) It was noted that in the Protection Sub-Committee meeting held on 23rd August 2011 SR-II, Power Grid had stressed about the immediate need for SPS at Hosur S/S till ICT-III got commissioned. This was in order to avoid overloading of the surviving ICT in case of tripping of one ICT. After deliberations, Protection Committee had recommended that TANTRANSCO may identify the loads which could be tripped in contingency to avoid overloading of ICT at Hosur. PGCIL & TANTRANSCO had been requested to examine the feasibility of automatic shedding of the loads.

b) In the 63rd OCC meeting, TANTRANSCO had pointed out that all the feeders were tie feeders and hence tripping of any one of the feeders may not contain the overloading problem. TN SLDC would however take corrective action by giving suitable directives in case of contingency. Further the ICTs can also be overloaded upto 120% for a short duration of

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time. It was pointed out that TN was to identify radial loads as per the deliberations in Protection Committee. SRTS-II, PGCIL had suggested that the detailed automated scheme for tripping of radial feeders could take upto 8 months time for implementation. Meanwhile, tripping of any identified feeder should be allowed at Hosur S/S immediately so as to avoid tripping of the surviving ICT. TANTRANSCO/PGCIL had been requested to deliberate and revert back by next OCC.

c) PGCIL had emphasized the immediate need of identifying the feeder which could be tripped during overloading of ICT. In the meeting, POWERGRID had suggested to trip 230 KV Hosur feeder, whenever the ICTs at Hosur were getting overloaded.

d) It was earlier informed by TANTRANSCO that they had already proposed to trip 230 KV Yerandahalli feeder at Hosur S/S, in the event of tripping of one of the ICTs to avoid over loading of the second ICT.

e) It had been noted in the 68th OCC meeting that the proposed SPS would be discussed in the forthcoming PCC meeting of SRPC.

f) 69th OCC: After discussions, it was agreed that a separate meeting on this issue would be held on 20th March 2012 at Bangalore with the participation of TANTRANSCO, KPTCL, SRLDC and SRPC Secretariat.

3.3.2 In the meeting, MS i/c requested TANTRANSCO to concur for the SPS scheme

that had been finalised in the Special Meeting held on 20th March, 2012 (Minutes

at Annexure - II). The SPS scheme was a system requirement needed to save

the Hosur ICTs from overloading. TANTRANSCO informed that it would be

difficult for them to convince their management since inter state lines from AP

such as 230 KV Chittor-Tiruvalam and 230 KV Sulurpet-Gummidipoondi are

tripped for any constraint in the up stream. Further, it contended that as

Vinnamangalam being a tie feeder and very old line, it was difficult for them to trip.

They said that 230 KV Hosur – Yerandahally feeder and in addition Kempatty

loads could be shed for the 400 KV Hosur ICT overloading SPS scheme. MS i/c

and SRLDC pointed out that loads in TN would not get affected and only the flows

would be rearranged. After discussions, TANTRANSCO said that they would put

up this issue to their management.

3.4 SPS for 400 KV Hiriyur – Nelamangala D/C Line


a) KPTCL had earlier informed that the Power System Study Group of KPTCL had been requested to study and analyse the load flow conditions consequent to the commissioning of the following lines and units:

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i) 400 KV BTPS – Hiriyur DC line

ii) 220 KV Hiriyur – Gowribidanur line

iii) 2 Nos. 500 MW units at BTPS

b) In the 67th OCC meeting, KPTCL had been requested to expedite the issue. It was informed by KPTCL that the SPS was being worked out in consultation with RT, KPTCL Zonal Chief Engineer, Bagalkot, JSW and KPCL. Further, GM, SRLDC had stated that the SPS on 400 KV Hiriyur – Nelamangala D/C Line was needed to be in place before the commissioning of the second unit of Bellary TPS.

c) In the 69th OCC meeting, Karnataka had informed that the second unit of BTPS was likely to come up by 2nd or 3rd week of March-2012. SRLDC reiterated that without SPS in place for the 400 KV Hiriyur – Nelamangala line, the COD of the new unit would not be possible. SRLDC had said that all new generating units must be with RGMO features. It was suggested by the forum that a check list of the requirements could be prepared by SRLDC and circulated to the Generators.

3.4.2 In the meeting, KTPCL informed that tower-to-tower inspections were being

carried out and the Hiriyur – BTPS line was likely to be ready in a couple of days.

The COD of BTPS Unit II was expected in April-2012. The SPS will be

implemented soon after the commissioning of 400 KV BTPS – Hiriyur line.

3.5 SPS for Vijayawada – Nellore Line


a) In the 66th OCC Meeting, Andhra Pradesh had been requested to arrange a coordination meeting with IPPs & SRTS I for early implementation of SPS on Vijayawada – Nellore D/C 400kV line. It had been noted in the meeting that the issue was also discussed in the 18th SRPC Meeting held on 23rd December 2011. POWERGRID had informed that discussions with APTRANSCO/IPPs were underway.

b) In the 69th OCC meeting, SRLDC had brought to attention that at times, when AP was under-drawing TN & Kerala were over-drawing with the loading on 400 KV Vijayawada – Nellore lines being about 590 MW per circuit. It was noted that the implementation of the SPS scheme was pending for considerable time. SRLDC further stated that in the 17th SRPC Meeting, it had been informed by AP that 400 KV Vijayawada- Malkaram line would be commissioned by February 12. AP stated that backing down instructions received from SRLDC during contingency were always being implemented. After discussions, it was resolved that the SPS scheme on 400 KV Vijayawada – Nellore lines would be implemented by 15th April 2012.

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3.5.2 In the meeting, to a query from SRLDC, AP informed the Members that the SPS

related works were expected to be completed as per the target date of 15h April,

2012.

3.6 Unit Tripping Issue at Talcher Kaniha on account of SPS Operation

3.6.1 The following was noted since 67th OCC meeting onwards:

a) AGM, NTPC had informed about the incident on 13th September 2011, when Unit 6 of Talcher had tripped on “HVDC Inter Trip Operation”. Unit No. 5 had also unloaded by 150 MW. In this regard, NTPC letter dated 28th December 2011 was also referred. It was indicated in this letter that

NTPC had been asked by SRLDC to revise the DC based on the availability of balance two running units. Unit 3 was already under shut down for annual maintenance works. UI had got suspended from 55th to 57th block because the outage was caused by grid factors. Accordingly NTPC Talcher had requested for reduction in DC from 58th block at 900 MW based on the availability of two units.

b) MS I/c, SRPC had stated that ‘DC’ declaration was within the purview of NTPC while SRLDC would limit themselves to scheduling. NTPC units had tripped on account of fault on Talcher-Kolar links and thus DC should not get affected.

c) AGM, NTPC had said that they had sought revision in the logic of SPS 1000 operation. In the proposed logic, the flow on 400 kV Talcher – Rourkela line would also be considered along with the availability of lines. This matter had been taken up by NTPC Corporate Group with NLDC. In the proposed scheme, no unit tripping was envisaged and in the worst scenario unloading of all six units of Talcher (Stage I & II) was proposed.

d) AGM, NTPC had also said that in the above instance of tripping, the issue was different. The generation level at Talcher Stage II was less, while additional power was being wheeled through the Talcher – Kolar link. There was no facility in place to cut off the additional power from other sources in event of pole outage. Forced outages of Talcher Stage II units were thus taking place causing loss of generation, additional fuel oil consumption etc. He had said that some means had to be devised so that the availability of Talcher II units was not affected. Further, in case of such outages, the DC of Talcher Stage II units should also not get affected in any manner.

e) GM, SRLDC had said that in such an event, the time taken by the tripped unit to come back after the HVDC Poles come back may also need to be clearly defined.

f) It was informed by NTPC that the unit would normally take three hours’ time to come up after tripping. It was agreed by OCC that NTPC be allowed to continue with the declaration of DC (already made) for a period of three hours after the poles come back. Further NTPC would not be asked to revise the DC in the eventuality of unit tripping on account of

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SPS operation. The REA for September 2011 would be revised as per the prevalent DC declaration made by NTPC just before tripping of Unit 6 due to SPS operation.

g) GM, SRLDC had stated that SRLDC would come back on this matter in the next OCC meeting, since commercial and other implications were involved. Further he had stated that there was an important issue regarding DC declaration by Talcher Stage II. Less DC was being declared in real time compared to the Day Ahead DC leading to blocking of the margin available in the corridor.

h) MS I/c, SRPC had stated that this aspect also needed to be examined in a closer manner, especially in the current high deficit scenario, in which the corridors were already over booked and there was a requirement for curtailment. He had added that SRPC Secretariat were also having certain observations regarding the DC declaration of Talcher Stage II.

i) In the 68th OCC meeting, it was informed that a meeting subsequently conducted in this regard at Hyderabad on 25.01.2012 was attended by NTPC, SRLDC and SRPC secretariat. The observations of SRLDC (as stated in 67th OCC) were awaited. The revision of REA for September 2011 would be taken up after receipt of observations from SRLDC.

j) In the 69th OCC meeting, NTPC had contended that 3 hours time period was required for bringing back the unit affected during the HVDC pole outage. Additional 7 to 8 blocks are also to be provided for ramping up of the unit to full load. After discussions, it was agreed that NTPC would submit its written observations with respect to the SRLDC letter. The matter would be further discussed in the ensuing Meeting of Commercial Sub Committee.

3.6.2 In the meeting, NTPC requested for revision of REA for the month of September

2011 in respect of Talcher II, based on the approved methodology. TN

requested that similarly messages to the constituents for overdrawal at low

frequency (Type A, B & C) be curtailed during SPS operation at Talcher-Kaniha.

3.7 Physical, Cyber Security in power supply

3.7.1 The following was noted in the earlier meetings:

a) In the 63rd OCC Meeting, it was noted that a meeting was taken by Member (GO&D), CEA on 9th August 2011 regarding Physical, Cyber Security in power supply. After detailed deliberations, it had been agreed that the activity of monitoring of Crisis Management Plan for countering the cyber attacks and its implementation including the Mock Drills, audits etc. by all the Power Utilities on a regular basis would be monitored by the Regional Power Committees. In the OCC Meeting, it was decided that all the constituents including RLDC/SLDC would furnish the status of measures taken to counter the cyber attacks in their system along with mock drills, audit etc.

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b) In the 65th OCC Meeting, MS I/c, SRPC had informed that detailed information as received from SRLDC had already been circulated in the earlier OCC meeting. He had said that information on similar lines needed to be furnished by the other constituents also. In this regard, letter dated 03rd November 2011 received from APTRANSCO had been circulated.

c) This issue was also discussed in the 18th SRPC Meeting held on 23rd December 2011. In the meeting, the constituents had been requested to furnish the necessary details so that monitoring could be taken up by the RPC forum.

d) In the 69th OCC meeting, MS i/c had informed that CEA had recently addressed letter dated 01st February 2012 stating that India Smart Grid Task Force (ISGTF) had requested to furnish the status in this regard. CEA had sought the action taken and the present status of preparation of Crisis Management Plan (CMP). Accordingly, the Constituents were requested to speed up the cyber security measures for their system. He also informed that TN had submitted certain details of implementation. A summary of the cyber security measures implemented by SRLDC were summarized and presented by SRPC to the constituents.

3.7.2 It was noted that AP, TN, and SRLDC had initiated certain cyber security

measures and had also submitted certain details to the forum. Karnataka and

Kerala informed that efforts were on to implement cyber security measures and

details would be duly informed.

3.8 Coal Stock Position

3.8.1 It was noted that as per CEA norms, coal stock position is termed as critical (< 7

days) or super critical (< 4 days) of coal stock. The daily Coal stock position

report as on 29th March 2012 as downloaded from CEA website is furnished at

Annexure - III. It was noted that the coal stock position in the following

Thermal Stations was less than that for 7 days generation:

State Station Days Reasons

AP Rayalaseema 4 Less Receipt

Simhadri 3 Higher Generation

KA Raichur 2 Less Receipt

Bellary 3 Less Receipt (C.B.)


a) It was noted that issue regarding Coal Stock position and other associated issues was also deliberated in the 18th SRPC meeting held on 23rd December 2011. SRPC had suggested that generators maintain the coal stock position as per norms to avoid any loss of generation.

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b) OCC had expressed serious concern over the low coal stock being maintained by the generating units. It was felt that higher forum needed to be again apprised of the situation to identify appropriate remedial action.

c) OCC had also expressed concern over NTPC not furnishing the requisite information in the format though all the generators of Southern Region were furnishing this information. OCC had again requested NTPC to furnish the information in the format given below:

Coal Stock Position

Generating Company: ……................. Month: ...................

Name of the station Name of the Station Name of the station

Statutory Requirement

Minimum coal stock in the month

Coal stock as on last day of the month Steps taken

to supple-ment stock

Time by which

position likely to improve

In lakh T

In no. of

days

In lakh T

In no. of days

In lakh T In no. of

days

Signature: .......................

Designation: ……………….. Contact Tel. No:…………………

d) AGM, NTPC, Talcher had informed that as already informed in the 66th OCC Meeting, Talcher had less receipt of domestic coal in the current year 2011-12 compared to last year. However, they had received more quantity of imported coal from previous year. NTPC was thus forced to generate as per coal receipts considering both indigenous and imported.

e) In the 67th OCC, EE, KPCL had informed that efforts were on to import additional coal and the contract was being finalized. The matter had also been discussed with Government of India. It was also again urged to NTPC that they may consider availing more quantity of imported coal, in case domestic coal was not available so that the generation levels were not reduced.

f) In the 68th OCC meeting, MS I/c had said that as informed earlier the matter regarding coal supply had been taken up with M/s MCL and also with CEA.

g) In the 69th OCC meeting SRLDC had informed that during high level discussions regarding scheduling of power from RGCCPP Kayamkulam, issue regarding shortage of fuel had also figured. KSEB informed that Kayamkulam was presently scheduled (for around 150 MW) in view of the annual school/college exams in the state. It was noted that issues regarding scheduling of RGCCPP Kayamkulam could only be taken up at a higher forum for decisions.

Information furnished by APTRANSCO, KPCL & TN is given in Annexure - IV.

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3.9 Facilitation of Inter-State/Inter-Regional transfer of power & utilization of IPPs

3.9.1 On a review of the bilateral exchanges made by the constituents and also by the

embedded IPPs during March -2012, the following was noted:

a) Imports (inter-regional) were done by: AP, Karnataka, Kerala & TN

b) Imports (intra-regional) were done by: AP, Karnataka, & TN

c) Exports (inter-regional) were done by: Nil

d) Imports done by utilities in: TN & Karnataka

e) Exports done by utilities in: Karnataka & Lanco

Details of Energy interchanges between the constituent systems and exchanges

with the other regions are given at Annexure – V (as per PSP).

3.9.2 The constituents were being requested to furnish details of any

requirement/surplus (quantum, period, time of day, tentative rates, etc.) along

with details of contact person to enable SRPC to post this information on its

website, to enable faster buyer/seller interaction.

3.9.3 It was also noted that Andhra Pradesh, Karnataka, Kerala & Tamil Nadu had

furnished the relevant details regarding energy exchanges through Power

Exchanges (Annexure - VI).

3.9.4 In the 69th OCC meeting, Constituents had desired that extended-mode (i.e. 10

hours @ 2500 MW) of HVDC Talcher – Kolar link may additionally cover time

required for ramping up and ramping down also. PGCIL had expressed its

inability in this regard and stated that the outer limit for extended mode operation

was 10 hrs which included ramping up and ramping down time also. SRLDC

informed that due to this requirement for ramping up and down, certain other

transactions may get curtailed for few time blocks during the extended mode of

HVDC Talcher-Kolar link. After discussions, it had been agreed that this issue

would be put up for deliberations in the ensuing TCC/SRPC Meetings. SRLDC

had also said that that extended mode operation of 2500 MW for 10 hours on a

daily basis was recently committed by POWERGRID before Hon’ble CERC

without any time limits.

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3.10 Generation Schemes scheduled for 2011-12

3.10.1 Progress of generation schemes scheduled to be commissioned during 2011-12

was reviewed. The updated information as furnished by the constituents is given

at Annexure - VII.

3.10.2 DGM, SRLDC presented the list of important generating schemes, transmission

lines and generation evacuation lines under construction (Annexure - VIII).

SRLDC again requested the constituents to furnish the updated information of

these important elements/stations in the OCC Meeting. They said that this

matter was being discussed in the OCC Meetings so that the states could

identify and monitor all lines (ATS) which are to be necessarily available during

unit commissioning to avoid evacuation bottlenecks at a later stage. SRLDC also

sought the status of commissioning of Vijayawada-Malkaram 400 KV line which

was scheduled for March 2012.

3.11 Pump mode operation of Kadamparai and Srisailam

It was noted that Kadamparai machines had consumed about 25.59 MU in pump

mode during the month.

3.12 Minimum to Maximum demand ratio

3.12.1 It was noted that Members were aware that the matter regarding wide variation

between maximum demand and minimum demand was being regularly taken up

with the constituents in the OCC Meetings. The details of percentage variation

between maximum and minimum demand for the month of March 2012 are

given below:

State Maximum to Minimum Demand Variation %

Highest Lowest Average

Andhra Pradesh 34.64(12

th )

(Monday)

11.06(6th )

Tuesday 18.20

Karnataka 27.08(11

th )

Sunday

12.25(22nd

)

Thursday 18.15

Kerala 43.95(5

th )

Monday

30.06(28th

)

Wednesday 37.27

Tamil Nadu 25.88(7

th)

Wednesday

10.61(28th

)

Wednesday 15.13

Puducherry 35.81(9

th)

Friday

16.77(4th

)

Sunday 25.66

Southern Region 16.64(7

th)

Wednesday

9.18(6th)

Tuesday 12.67

Note: Highest and lowest have been computed from daily values over the month.

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3.12.2 It was requested that the constituents initiate all possible measures to ensure

appropriate Demand Side Management and Energy Efficiency Programmes

considering that there were sizeable energy and demand shortages in the States

with capacity addition generally not matching with demand growth in addition to

also limitations in possible import of power. MS I/c, SRPC informed that the

SRPC/TCC were also appraised of the above in the recent meeting. The

constituents were requested to come out with specific details of proposed new

approaches to Demand Side Management so that these recommendations could

be put up to TCC/SRPC. KPTCL had informed that ESCOMS had shifted a

portion of the load from peak hours to off peak hours.

3.13 LGBR forecasted figures vs. Actual Figures

It was noted that the variations between actual and forecasted availability/

requirements LGBR figures were more than 10% in respect of the following States

during March-2012:

Forecasted Actual Deviation

from Actual %

Variation Reason

a b c=b-a d=c/a

Andhra Pradesh

Energy Availability 6,736 8,221 1485 22

Karnataka

Energy Requirement (MU) 5,489 6,416 927 17 Higher growth

Demand Requirement (MW) 8,680 10,545 1865 21

Kerala

Energy Availability (MU) 1,687 1,888 201 12 Higher hydro utilization and purchases

Tamil Nadu

Energy Availability (MU) 6,674 5,980 -694 -10 50 to 60 MU/day load shedding

3.14 MoP Generation Targets vs. Actual

Details showing more than 10% gross generation shortfall with respect to MoP target

figures for March -2012 are tabulated below:

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Mar-2012

(%) Cumulative

(%) Reasons for shortfall (>10% in MU) in gross generation

Andhra Pradesh

Hydro -33 -20 Decreased inflow into reservoirs.

Private sector -31 -17 Shortage of gas supply

Karnataka

Diesel -45 -27 LSHS shortage; Merit order constraints.

Private sector -25 -42 Merit order constraints.

Kerala

Diesel -29 Merit order considerations.

Private sector -90 -79 Merit order considerations.

Kayamkulam -49 -65 Merit order considerations.

Tamil Nadu

Coal -33 Tripping of two units at NCTPS.

Gas -40 Merit order considerations.

Private sector -16 Merit order considerations.

ISGS (Coal)

Simhadri-II -37 -21 Shortage of coal.

During discussions, with reference to RGCCPP Kayamkulam power, KPTCL

expressed that it would be difficulty for any utility to prepare proposal for power

purchase without knowing the cost of the power. Other members also wanted to

know the cost of Kayamkulam power, in case it was scheduled fully for 24 hours.

SRLDC said that RGCCPP Kayamkulam should be scheduled fully especially in

view of the S1 – S2 transmission constraints and also in view of the shortages.

RGCCPP could consider sale of power through Power Exchange. They added that

in the present power market, the competitive price was ranging between Rs 10 to

Rs 19 during the day in S1 and S2 bid areas.

3.15 Forced outages of thermal units

3.15.1 MS I/c, SRPC said that in the recent TCC/SRPC meetings, the Generators were

apprised of the concerns raised by the SR constituents, CEA, MoP etc. over the

high quantum of forced outages. It was noted that the forced outages of thermal

units had varied between 2.77 – 5.96% during the month of March 2012.

3.15.2 OCC was apprised of the forced thermal outages of more than 24 hours duration

during the month of March 2012 (Annexure - IX). OCC recommended that the

planned/preventive maintenance be carried out as per the schedule to reduce

the instances of forced outages.

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3.16 Prolonged outages

3.16.1 OCC was apprised of prolonged outages in Southern Region during the month

of March 2012 (Annexure - X).

3.16.2 MS i/c, SRPC pointed out that Hon’ble Commission was also monitoring the

instances of prolonged outages and hence requested the constituents to furnish

the required information regularly to SRPC/SRLDC for further needful.

3.16.3 The following was noted during discussions in the Meeting:

a) Srisailam pumps were expected to be ready by second week of May -2012.

b) TN informed that ETPS unit IV which was out from 5th October 2011 had come into the grid on 7th April 2012.

c) 400kV line from Kudankulam to Thirunelveli (ckt II) was under prolonged outage.

d) Puducherry-Bahoor and Puducherry - Villianur lines which were out from 30th December 2012(due to cyclone Thane) were in service from 27th March 2012.

3.17 Generation levels at NPCIL Units

It was noted that this issue was deliberated in the 18th SRPC meeting held on 23rd

December 2011 wherein NPCIL had informed that the generation level would

continue to be maintained at around 65 - 70%.

3.18 IPP Utilization

OCC was also apprised of the PLFs of the IPPs operating in Southern Region

during the month of March 2012 (Annexure - XI).

3.19 Generation targets for the year 2012 - 13


a) In the 67th meeting, the following had been noted:

i) MS i/c, SRPC had said that as already informed CEA had sought information regarding thermal generating units including IPPs for assessment and finalization of generation targets for the year 2012-13. The same had been communicated to the constituents vide letter dated 29th September 2011. He had requested that the information be communicated to CEA with a copy to SRPC Secretariat.

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ii) The forecast figures for energy requirement and demand requirement for 2012 -13 had been circulated during the 64th OCC meeting. SRPC had requested the constituents to examine the figures and revert back with comments, if any, since the same was to be considered for the Annual LGBR for 2012 -13. He had also informed that a meeting had been convened by CEA at Bangalore on 20th January 2012 to discuss the issue further with the concerned utilities.

iii) In the 68th OCC meeting, SE-I had said that a meeting was taken by CEA at SRPC on 20th January.2012 regarding finalization of the Annual Generation Targets for the year 2012-13. He had also informed that the Outage Plan for 2012 - 13 had been circulated and discussed in that meeting. The Outage Plan had been approved and had been hosted on SRPC website. He had said that certain data for the preparation of Annual LGBR 2012-13 was awaited from some of the utilities and therefore requested the concerned constituents to submit this data immediately.

3.19.2 Ministry of Power has approved Annual Generation Targets for the year 2012-13.

All the constituents were requested to make all efforts to achieve the targets as set

for their organizations.

3.19.3 In the 18th SRPC meeting, it had been decided to obtain coal and gas supply

position from the states for taking up the matter with CEA. The states had been

requested to send the gas supply position to SRPC Secretariat for further needful.

OCC noted in the previous meetings that the present gas availability of Gas

Stations of TANGEDCO had varied between 75 % to 100 %.

4. LOW FREQUENCY GRID OPERATION

4.1 MS I/c, SRPC pointed out that the frequency of operation of the Southern Regional

Grid was less than 49.5 Hz for about 8.07% of the time during March 2012. Mutual

support / cooperation was the need of the hour to operate the grid in a safe and

secure manner. He said that concerted efforts were required by the constituents to

operate the grid within IEGC parameters. DGM, SRLDC stressed on suitable

demand side management by the constituents. Details of caution/violation

messages issued by SRLDC to the constituents during the month of March 2012 are

given at Annexure - XII.

4.2 OCC placed on record appreciation for Andhra Pradesh, Karnataka, & Puducherry

for not having received any Type ‘C’ message during the month.

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4.3 DGM, SRLDC said that 12% violation messages of Over Drawal / Under Injection

while frequency was below 49.7 Hz over a time block were on the higher side as

given below:

Number of 12% violation messages

Constituent March 2012 April 2012 (up to 4th

)

Andhra Pradesh 488 55

Karnataka 43 15

Kerala 285 97

Tamil Nadu 935 78

Puducherry 0 0

Lanco 134 0

Total 1885 245

He added that the States needed to put more efforts to curtail the instances of

overdrawals. As informed in earlier meetings, the details in this regard were being

regularly communicated to Hon’ble CERC.

4.4 APTRANSCO informed that even with purchases and resource management, the

State had to face demand & energy shortages. Load shedding upto 3222 MW

amounting to about 1313 MU had been carried out during March -2012. Details of

Load relief imposed during the month of March 2012 are given at Annexure - XIII.

4.5 KPTCL informed that load shedding in the State upto 2430 MW amounting to about

873 MU for the month had been carried out. 3-phase supply was being ensured to

the agricultural consumers for six hours during day time between 6 AM to 6 PM in

two batches while single phase power supply was being ensured between 6 PM to 6

AM (next day). Strict grid discipline was being adhered though the demand had

gone up drastically and nil messages were issued to them during March 2012.

4.6 KSEB informed that with purchases they were able to maintain load generation

balance in their system. Need based load shedding up to 300 MW amounting to

about 21 MU had been carried out during March 2012.

4.7 TANTRANSCO said that load shedding up to 4653 MW amounting to about 1880

MU was carried out during the month. They briefed about the load restriction

measures in their system for March 2012 which is given below:

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40% in respect of HT Industrial and Commercial consumers

2 hour Load Shedding increased for Chennai (between 0800 hrs to 1800 hrs.)

4 hour Load Shedding for urban and rural Areas (between 0600 hrs to 1800 hrs.)

One day Power Holiday for industries apart from regular Sunday holiday.

Agriculture was being fed 6 hours of three phase supply in day time and 3 hours of three phase supply in night time.

They added that both the 230 KV Chittor-Thiruvalam and 230 KV Sulurpet-

Gummidipoondi inter state lines were kept open based on SRLDC instructions on

5th April 2012 during the outage of 400 KV Vijayawada- Nellore lines, depriving

even the restricted quantum of 120 MW flow from AP.

4.8 It was also noted that the second follow up meeting among TN, SRLDC & SRPC

Secretariat was held at Bangalore on 28th September 2010 in line with the directions

of CERC Adj No: 6/2009 (dated 27th April 2010). MS I/c, SRPC had requested

TANTRANSCO to furnish the progress regularly as decided in the Meeting so that it

could be communicated to the Hon’ble Commission. Pre-approved contingency

plan to take care of intermittency of wind was still awaited.

4.9 OCC observation

MS I/c, SRPC summarized the deliberations as follows:

Action on the recommendations of the Special TCC Meetings held on 29.03.2011 & 27.03.2010 should be planned and implemented in a definite time frame.

Constituents should continue with sustained efforts to avoid any threat to system security and effectively plan their load generation balance on a day-to-day and hour-to-hour basis to meet this objective.

All constituents shall endeavour to maintain load generation balance and frequency shall be maintained above 49.5 Hz.

Action for curtailment of overdrawals to be initiated at 49.7 Hz itself to avoid any overdrawal below 49.5 Hz.

Automatic Load Disconnection Scheme to be operational to provide desired reliefs.

All the available unutilized generation in the region should be arranged to be scheduled immediately as warranted by system requirements to meet the demand and also to help restrict overdrawals, especially when the frequency of operation was low, with appropriate commercial arrangements in place among constituents.

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Constituents to plan effectively so that the overdrawals and exports, if any, did not take place simultaneously at low frequencies.

TNEB to plan and implement the decisions taken in the meeting held on 12th July 2010 & 28th September 2010. Till such time, L/S & R&C measures need to be carried out to curtail overdrawals at frequencies less than 49.5 Hz.

Contingency plan for intermittency of wind to be finalized and implemented by TN.

UFR & df/dt relays to be operational at the recommended set points to provide desired reliefs.

Grouping of feeders in four categories to be completed, as per provisions of IEGC.

Feasibility of implementing Karnataka load management model (at 220 kV levels) in other constituent systems to be examined.

Implementation of forecasting tools for short term forecasting, with weather as input.

Compliance Report furnishing the action taken in response to Type ‘C’ messages should be communicated in writing to SRLDC.

DSM measures to be identified and implemented.

4.10 Arranging of interruptible loads in four groups

4.10.1 In the earlier OCC meetings, it was noted that as per IEGC, to maintain the

frequency within stipulated band and also to ensure network security, the

interruptible loads were to be arranged in four groups of loads. This was for the

purpose of scheduled power cuts/load shedding, loads for unscheduled load

shedding, loads to be shed through UF relays, df/dt relays and loads to be shed

under any SPS Scheme. These loads were to be grouped in such a manner

that there was no overlapping between different groups of loads.

4.10.2 It was noted that Andhra Pradesh, Kerala & Tamil Nadu had completed this

exercise. Puducherry had initiated action in this regard.

4.10.3 KPTCL had informed that it had taken all measures to stick to its share during

low frequency conditions.

4.10.4 MS I/c, SRPC informed that in last few SRPC/TCC meetings constituents had

been informed of the requirements in this regard. He requested Karnataka &

Puducherry to complete the exercise in their respective systems and inform to

CERC/SRLDC/SRPC Secretariat.

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4.11 Automatic Demand Management Schemes

4.11.1 Automatic Demand Management Scheme in line with clause 5.4.2 (d) of the

IEGC was to be provided by all the constituents by 01.01.2011.

4.11.2 It was noted that Andhra Pradesh, Kerala & Tamil Nadu had implemented the

scheme. Puducherry had also initiated action in this regard.

4.11.3 KPTCL had informed that had taken all measures to stick to its share during low

frequency conditions and to overdraw during high frequency by reducing hydro

generation to the maximum extent for maintaining grid discipline as per IEGC

standards.

4.11.4 SRLDC & SRPC Secretariat requested KPTCL also to expedite the

implementation of the scheme in its system in line with IEGC provisions, since

the scheme had already been approved by SRPC and was mandated as per

IEGC.

4.11.5 It was also suggested that constituents could identify other Demand

Management Schemes other than Automatic Load Shedding Schemes.

4.12 Automatic Load Disconnection Schemes for overdrawing constituents

4.12.1 It was noted that SRPC in its 14th meeting held on 27th August 2010 had agreed

to implement Automatic Load Disconnection Scheme for overdrawing

constituents with the following relief:

Sl.No. Constituents Load Relief

1 APTRANSCO 450 MW

2 KPTCL 350 MW

3 KSEB 125 MW

4 TNEB 650 MW

5 Puducherry 25 MW

4.12.2 KPTCL had earlier informed that 350 MW of load relief through remote tripping

of load under crisis period has been identified. The same is under testing and

final implementation stage and would be implemented shortly.

4.12.3 It was noted that the above scheme was part of Automatic Demand

Management Scheme which had been discussed in para 4.11 above. It was

noted that Puducherry had provided remote tripping facilities in the identified

feeders in order to provide emergency disconnection.

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4.13 On Line Demand Estimation

In the earlier OCC meetings, it was noted that all the states were furnishing the 15

Minute requirements. The constituents were apprised that the forecasting tool

should take into account weather inputs as well.

5. GRID OPERATION

Different aspects of grid operation were reviewed and the following grid events were

noted. Grid operation data for March 2012 is enclosed as Appendix - A.

5.1 Grid events during March 2012

Frequency remained within IEGC range (49.5 - 50.2Hz) for 91.75% of time (February 2012 – 94.34%, March 2011 – 80.40%).

Frequency remained below 49.5 Hz for 8.07% of time and average frequency for the month was 49.64 Hz.

Frequency remained above 50.2 Hz for 0.18% of time.

Andhra Pradesh, Karnataka and Kerala met a maximum demand of 11972 MW (19th March), 8549 MW (27th March), and 3348 MW (19th March) respectively which were the maximum till date

Southern Region met a maximum of 33,037 MW (30th March) which was the maximum till date.

Karnataka met a day maximum consumption of 190.21 MU in March which was the maximum till date.

Kerala met a day maximum consumption of 63.46 MU in March which was the maximum so far.

The following were the additions to Installed Capacity to SR Grid during the month:

State Sector Type Station Capacity

(MW) Date of

commissioning

AP Private Solar Solar 3 March 2012

KAR State Solar BTPS Unit 2 500 23rd

March 2012

KAR Captive (JSWEL)

Thermal Thorangallu (Unit 2)

300 23rd

March 2012

TN Private Wind Wind 234.1 March 2012

TN JV NTPC/ NTCEL

Private Vallur St I Ph I Unit-1

500 28th March 2012

CENTRAL (AP)

Central Thermal

Simhadri Stage II Unit 2

500 30th March 2012

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The following were the Transmission lines added in SR system during the month:

State Line Name Voltage Length in ckt

kM Date

AP

220kV DC XLPE UG cable from 400/220 kV Malkaram S/s to proposed 220 kV S/s at Gunrock(Conventional S/s) (by APTRANSCO)

220 32.10 31.03.2012

AP 220 kV LILO to Jurala HEP from 220 kV Veltur-Jural ckt I & II (By APTRANSCO)

220 0.32 22.03.2012

AP 2

nd ckt of 220 kV Budidampadu-

Mirayalaguda line of 99.09 ckm (By APTRANSCO)

220 99.09 31.03.2012

TN 230 KV Kalpakkam - Arni D/C line (By POWERGRID)

230 213 26.03.2012

KAR LILO of both ckts 400 KV D/C Nelamangala-Somanahalli at Bidadi s/s (By POWERGRID)

400 28 March 2012

Following Sub-stations were commissioned during the month

State Station Name ICT No & MVA

KV Ratio Date

AP Jurala by APTRANSCO ICT 1 1x100

220/132 22.03.2012

KER Chulliyar (Palakkad) By POWERGRID

ICT I & II 2x315

400/220 ICT I in Feb 2012 ICT II in March 2012

KAR Bidadi(GIS) By POWERGRID

ICT I 1x500

400/220 March 2012

5.2 The Table below furnishes the details of actual Maximum Demand met (MW) &

Average Energy Consumption per day (MU) in respect of the SR constituents for

March 2012 vis-à-vis March 2011. The maximum daily consumption by the

respective constituents during March 2012 is also included.

System

Actual Maximum Demand (MW)

Average Consumption/day (MU)

Max. Daily Consumption during March

2011 (MU) March 2012

March 2011

%-age March 2012

March 2011

%-age

a b c=(a-b)/b d e f=(d-e)/e

Andhra Pradesh

12,449 12,254 1.59 263.18 264.90 -0.65 269.35

Karnataka 8,726 7,937 9.94 181.45 166.87 8.74 190.21

Kerala 3,348 3,119 7.34 59.82 54.71 9.35 63.46

Tamil Nadu 10,242 10,652 -3.85 195.74 224.26 -12.72 222.82

Puducherry 311 302 2.88 6.33 6.13 3.35 6.67

Southern Region

33,037 31,927 3.48 706.52 716.87 -1.44 732.61

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5.3 It could be seen from the above that the Peak Demand for all the constituents,

(except Tamil Nadu) had recorded a positive growth rate of 2 - 10 % whereas Tamil

Nadu showed a negative growth rate of about 4% as compared to March 2011

Southern Region as a whole had met a maximum demand of 33037 MW in March

2012, which was 1110 MW more than last year’s figure of 31927 MW. In respect of

average daily energy consumption also except Tamil Nadu and AP all the

constituents had registered a positive growth rate which varied from about 3 – 9%.

Tamil Nadu had recorded negative growth rate of about 13% and that of AP was

0.65%. Average daily energy consumption of Southern Region was slightly less

than during last year.

5.4 It was observed from the SR Load Duration Curve for March 2012 (Annexure -

XIV) that the maximum demand was more than March -2011 value for about 5% of

time and around 90% of time it was in between March -2011 and February -2012

values. Daily consumption figures were also presented (Annexure - XV).

5.5 Hydel Availability

5.5.1 The energy availability in major hydel reservoirs at the end of March 2012 vis-à-

vis that for March 2011 was reviewed, which is given below:

(Figures in MU) System

Reservoir Energy at FRL

Storage as on Inflows in March 2012

31.03.2012 31.03.2011 Anticipated Actual

ANDHRA PRADESH

Jalaput Srisailam (MDDL:243.8m) Nagarjunasagar (MDDL:149.3m)

495

269.8*

179.8*

305.76

(832.73)*

34.29 (246.31)*

22.594

(156.06)*

441

(835.97)

239 (255.42)

616

(170.32)

12

6

16

0

KARNATAKA

Linganamakki Supa

4547 3152

1726

850

1983 1032

30 18

29 40

KERALA

Idukki Kakki Total

2190

916 4131

724 442

1606

1048

466 1981

31 32

102

34 37 94

TAMIL NADU

Nilgiris Total (Excluding Mettur)

1504 2183

612 755

312 577

30 67

42 58

*Levels in meters

5.5.2 DGM, SRLDC pointed out that energy storage in the hydro reservoirs showed

around 12% deficit (666 MU) compared to same month last year and about 14%

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(784 MU) deficit compared to 9 years’ average. He stressed on appropriate

R&C measures during the coming months on account of the poorer hydro

position.

5.5.3 It was requested to continue the optimum utilisation of hydro, keeping in view the

energy storage position vis-à-vis management of demand/energy requirements

from the overall view of maintaining system parameters within IEGC limits and to

optimize the load generation balance.

5.6 System Frequency

5.6.1 It was noted that the SR frequency during the month of March 2012 was within

IEGC range for about 91.75% of the time, as compared to 80.40% of IEGC

range during March 2011.

5.6.2 It was also noted that the frequency of grid operation was in the lower range of

IEGC and had operated below 49.5 Hz for 8.07% of the time during the month of

March 2012. It was also noted that the frequency on some of the days was less

than 49.5 Hz for some duration as shown below:

Date

Percentage of time of frequency

Less than 48.5 Hz

48.5 Hz & < 49.0 Hz

49.0 Hz & < 49.2 Hz

49.2 Hz & < 49.5 Hz

01/03/2012 0 0 0 8.5

02/03/2012 0 0 0 14.4

04/03/2012 0 0 0 6.2

05/03/2012 0 0 0 6.3

06/03/2012 0 0 0 10.2

07/03/2012 0 0 0 8.1

09/03/2012 0 0 0 8.5

10/03/2012 0 0 0 9.4

13/03/2012 0 0 0.2 7.2

14/03/2012 0 0.3 0.7 10.1

15/03/2012 0 0 0 6

16/03/2012 0 0 0 10.8

17/03/2012 0 0 0 6.3

18/03/2012 0 0 0 14.1

19/03/2012 0 0 0.1 5.8

20/03/2012 0 0 0 5.8

21/03/2012 0 0 0 6.9

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22/03/2012 0 0 0 8.1

23/03/2012 0 0 0.1 16.4

24/03/2012 0 0 0 10.1

26/03/2012 0 0 0.3 10.5

27/03/2012 0 0.4 0.8 9.0

28/03/2012 0 0 0 13

29/03/2012 0 0 0 11

5.6.3 It was also noted that the Regional Grid had operated above 50.2 Hz for

0.18% of the time, during the month. It was also noted that the frequency on

some of the days was more than 50.0 Hz for some period of time as given

below:

Date Percentage of time of frequency

50.0 Hz & < 50.2 Hz More than 50.2 Hz

03/03/2012 1.2 0.6

08/03/2012 4.3 1

09/03/2012 2.1 0

25/03/2012 2.0 1.2

30/03/2012 2.2 0

5.6.4 OCC observed that grid operation below 49.5 Hz and above 50.2 Hz should

have been avoided since it violated the provisions of IEGC and also caused

threat to grid security. Operational control needed to be streamlined so that

uneconomic operation of the grid above 50.2 Hz is avoided.

5.6.5 DGM, SRLDC stated that the phenomenon of high frequency excursion during

load changeover continued to exist. The high frequency excursion was being

experienced during the changeovers and not restricted to evening peak hours

alone. For instances there were under drawal during high frequency conditions

by Andhra Pradesh (on 31st), Karnataka (on 8th and 31st), Tamil Nadu (on 8th,

13th, and 25th) during March -2012 (Annexure - XVI).

5.6.6 KPTCL said that as informed earlier they had taken all precautionary measures

by backing down hydro generation to the maximum possible extent without

under drawing from CGS during high frequency conditions. They were

monitoring the situation on a daily basis and the change over time had been

staggered by 15-20 minutes either by postponing & preponing. However at times

due to line loading issues, Karnataka was forced to under draw.

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5.6.7 The recommendations finalized in the 60th OCC are reproduced for

implementation please:

Karnataka & Tamil Nadu to finish their changeover during 1730 – 1800 hrs with proper staggering (evenly spread over).

Andhra Pradesh to finish their changeover during 1800-1830 hrs with proper staggering (evenly spread over).

Andhra Pradesh to decrease it’s under drawal during changeover period.

Improved coordination with Discoms required.

Each state to balance its load removal with matching generation reduction.

No loads should be taken out at frequency > 50.0 Hz.

Loads removal should preferably be frequency dependent rather than time dependent.

SLDCs may consider tripping of some of the feeders from their control room using SCADA.

States could plan automation of load changeover with reference to frequency.

All the units should participate in RGMO which would help moderate the impact of the changeover.

Proper training and awareness should be imparted to the officials handling the substations.

Generating stations including ISG stations should not inject excess power into the grid above 50.2 Hz.

It was noted that there were other frequency excursions during other changeovers and the recommendations needed to be implemented in respect of those periods also. All the constituents were requested to adhere to above recommendations to avoid excursion in frequency during changeover.

5.6.8 DGM, SRLDC said that RGMO/FGMO (characteristics of RGMO with manual

intervention) implementation in all the units would also help in easing the

situation. SRLDC also presented the Frequency Histogram & Frequency

Duration Curve (Annexure - XVII) for March 2012. He said that the regional

entities were being requested to furnish details to SRLDC to analyse and

ascertain effectiveness of RGMO/FGMO participation of individual major thermal

units in the region with respect to specific instances.

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5.6.9 A Special Meeting to discuss issues relating to load changeover had been held

on 8th March 2012 (A.N) after conclusion of the 69th OCC Meeting. SRPC had

presented Summary showing frequency excursions above 50 Hz in the last 5

months with time and number of occasions. After discussions, it was decided

that AP would postpone the load changeover by 10 minutes from the existing

schedule both during the morning and evening peak hours on 12th and 13th

March 2012. The results of this exercise would be deliberated in the 70th OCC.

5.6.10 As detailed by MS i/c during his opening remark, AP had shifted timing of load

changeover on 13th March and submitted the data to SRLDC. SRLDC stated that

on that particular day, the frequency excursion was not noticed. They also hoped

that with better coordination among the states, the sharp rise in frequency could

be contained. MS i/c complimented Andhra Pradesh for the cooperation

extended and efforts taken in load staggering. TN informed the Members that

every hour load shedding was being done in the state to overcome the severe

power shortage and said that they would be ready for similar load changeover

exercise by LDCs with a gap of five minutes amongst them on 20th and 21st April,

2012. The results of this exercise would be deliberated in the 71st OCC.

5.7 Under Frequency Relay

5.7.1 Andhra Pradesh, Kerala & Tamil Nadu had furnished the details about the

revised quantum which were finalized in the 59th OCC meeting.

5.7.2 KPTCL had informed that it had already implemented the additional load relief as

envisaged.

5.7.3 It was noted that Electricity Department, Puducherry had provided under

frequency relays in the identified feeders. Out of 12 feeders, 11 nos of feeders

had been provided with the U/F relays. (81 MW out of 84 MW)

5.7.4 Andhra Pradesh, Karnataka, Kerala & Tamil Nadu reported NIL UFR trippings.

5.7.5 It had been emphasized that the UFRs were meant for protection of the grid. As

stressed earlier, set points should not be changed in any manner. It had also

been stressed at higher levels that the UF Relays be made fully effective by all

the utilities so as to give the designated relief at specified frequency levels.

5.7.6 MS i/c, SRPC said that reasons for tripping at undesired settings needed to be

examined. Corrective action such as calibration is required to be taken to avoid

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such incidents in future. He also informed that as part of the annual exercise,

the quantum of UF relays had been reviewed and had been circulated

(Annexure - XVIII).

5.7.7 Tripping details like name of the feeder, load affected, date and time of the

tripping, frequency at the time of tripping and restoration time needed to be

furnished to SRLDC/SRPC regularly and in a timely manner. Constituents

agreed to furnish the details in a timely manner. It was also noted that the IEGC

stipulates that SLDC shall furnish a monthly report of UFR & df/dt relay operation

to the RPC.

5.7.8 TANTRANSCO informed that in the recent grid disturbance that had occurred on

3rd April 2012, owing to low frequency a load relief of 650 MW was realized from

TN. Similarly during the tripping of Talcher – Kolar Pole II on 29th February

2012, no other state except TN had reported any relief. They said that any

sudden loss of generation should be shared by all the constituents and not

burden any constituent. SRLDC was requested to ascertain the UF relay

operation in other states also during this disturbance.

5.8 df/dt Protection System

5.8.1 Andhra Pradesh, Karnataka, Kerala & Tamil Nadu had reported nil trippings.

5.8.2 MS i/c, SRPC said as informed earlier in the recent Protection Sub-Committee

Meeting, the settings of df/dt relays in the region had been reviewed and

accepted.

5.9 Inter-trip Scheme/ Modification of SPS

5.9.1 SRLDC had suggested modification of SPS for operation of HVDC Talcher-Kolar

bipole at 2500 MW level and also for load relief during the instances of tripping of

all units at Talcher Stage-II making zero flow in HVDC Talcher-Kolar bipole.

AGM, SRLDC enquired about the status.

5.9.2 It was noted that in the recent Protection Committee meeting, PGCIL had

informed that that the works on inter-trip signal III would be completed by end

December 2011. In the 67th OCC meeting, it was informed that the third signal

may be available by middle February 2012.

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5.9.3 Andhra Pradesh, Karnataka, Kerala & Tamil Nadu had reported Nil Talcher-Kolar

inter-trip operation.

5.10 The tripping details as furnished by the constituents are at Annexure - XIX.

5.11 On review of the performance of SPS for HVDC Talcher – Kolar link, it was

observed that Signal 2 was not getting generated and giving relief as per system

requirements. A Meeting was held on 29th march 2012 with the participation of

POWERGRID, SRLDC and SRPC. Certain changes in the SPS trip generation logic

were proposed and agreed. In the meeting, POWERGRID presented details of the

proposed modifications in the scheme (Annexure - XX). After discussions, it was

agreed that the modifications would be circulated to the constituents. Comments in

this regard were agreed to be furnished by 24th April 2012. In case no comments

were received by then, the revised logic would be put into effect from 01st May

2012.

6. ANTICIPATED AVAILABILITY AND CONSUMPTION FOR THE MONTHS OF APRIL- 2012 & MAY- 2012

6.1 OCC noted that information regarding anticipated availability & requirement for the

months of April and May 2012 furnished by the constituents and the same is

furnished at Annexure - XXI.

6.2 All the constituents agreed to initiate requisite measures to maintain appropriate

load generation balance in their systems, and adhere to the IEGC provisions.

6.3 Review of the availability during March- 2012

The Table below gives the anticipated availability as furnished in the 69th OCC

against the actual availability for the month of March 2012:

(Figures in MU)

State Anticipated availability

as given in 69th

OCC Actual

availability Deviation

(Actual – Anticipated)

Andhra Pradesh

241.85 253.90 +12.05

Karnataka 168.15 177.27 +9.12

Kerala 53.68 59.54 +5.86

Tamil Nadu 176.44 190.35 +13.91

6.4 It was noted that the load shedding in AP was around 37 MU per day and in Tamil

Nadu was around 60 MU per day.

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6.5 Tamil Nadu informed that they had to further enforce severe load shedding in the

state in order to keep the drawal under limit.

7. RESTRICTED GOVERNOR MODE OF OPERATION

7.1 The following was noted in the earlier Meetings:

a) RGMO operation was highly critical during load changeover. As informed earlier, NLDC had been submitting the status report of RGMO in various regions to Hon’ble CERC on a monthly basis. He pointed out that as per CERC Order on Petition No.237/2010, the units were required to be put on FGMO, in case RGMO operation was not possible. Either RGMO or FGMO should be in place for all the units as mandated under IEGC. If under FGMO, with manual intervention the units should be operated for the desired characteristics of RGMO.

b) KPCL had said that most of the thermal stations were using coal which was not as per the designed calorific value. The mills were therefore overloaded and there was no further provision for additional generation. DGM, SRLDC enquired that if that was the case, why the units were not reducing the generation when the frequency was on the upward trend.

c) MS i/c, SRPC had said that maximum number of units needed to be put in RGMO in the interest of the security of the grid. For any constraints for implementation of RGMO on particular units, exemption from CERC could be obtained.

7.2 DGM, SRLDC had pointed out that there was inadequate response from thermal

generating stations. In most of the instances Idukki, Varahi, Nagjhari, Lower Sileru,

Sharavathi, Kundah –I, II, III were responding for immediate increase and decrease.

SRLDC had been seeking unit wise MW generation/frequency/throttle valve plot

details in specific instances to analyze and ascertain the effectiveness of

RGMO/FGMO participation of major thermal units.

7.3 SRLDC presented the RGMO Analysis Summary (details in Annexure - XXII).

8. VOLTAGE PROFILE

8.1 High Voltage

8.1.1 In the 68th OCC meeting the following was noted:

SRLDC had expressed concern over high voltage conditions at Vijayawada and

Gajuwaka though both these nodes are near generating plants. He stressed the

need for reactive power absorption within the limits of machine capability curve

for keeping the voltages under check. He further disclosed that a mock-exercise

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was proposed to be conducted in the month of March 2012. At this juncture, MS

I/c suggested that a study could also be conducted to ascertain bus sensitivity to

reactive power absorption. MS I/c suggested that APTRANSCO, APGENCO and

SRLDC together could carry out the studies and the report of this study could be

presented to the OCC forum. TN informed that Gas stations in Valathur area

were not absorbing adequate reactive power and citing technical constraints for

the plant.

8.1.2 It was noted that Vijayawada, Gazuwaka and Thiruvanathapuram were facing

high voltage situation. There were 37 trippings due to over voltage of the 400 kV

lines during the month. It was noted that Jeypore - Gazuwaka I & II,

Vijayawada-Vemagiri I, Thirunelveli – Kundankulam III& IV lines were kept open

for more than 3 days due to over voltages.

8.1.3 SRLDC presented the high voltage graph for the nodes at Hyderabad,

Nagarjunasagar, Gooty, Vijayawada, Guttur, Kurnool & Nellore for 11th 12th ,

18th and 25th March 2012 when high voltage conditions had prevailed

(Annexure - XXIII).

8.2 Bus/Line Reactors to be commissioned

The updated information on schedule of commissioning of reactors as originally

agreed in the 22nd Standing Committee on Power System Planning of Southern

Region is furnished at Annexure - XXIV. KPTCL had informed that work of design,

supply, erection and commissioning of new 63 MVAR bus reactor at Guttur,

Talguppa, Nelamangala and Hoody had been awarded to M/s BHEL on turnkey

basis and works were under progress. In the meeting, DGM, SRLDC informed the

status of ongoing Bus/Line reactors installation based on the inputs received.

8.3 Re-commissioning of Reactor at Guttur/other Reactors

The issue regarding 50 MVAR line reactors on 400 kV Guttur-Birenahalli – I at

Guttur S/S and 400 kV Nelamangala-Hiriyur – II at Nelamangala was discussed in

the TCC meeting held on 29th April 2011 and number of OCC Meetings. KPTCL

had been requested to take up this issue with Standing Committee on Power

System Planning. Subsequently, CEE (LD), KPTCL had taken up the issue with

CEE (P&C), KPTCL vide letter dated 13th June 2011. CEE (LD), KPTCL informed

that reply dated 23rd July 2011had been received from CEE (P&C), KPTCL. In view

of the contents of the letter, the issue could be further deliberated at TCC level. In

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earlier forums it had been pointed out to KPTCL to take up the issue with Standing

Committee.

8.4 Low voltage

The following was noted in the earlier Meetings:

a) In the 59th OCC meeting, OCC had suggested that KPTCL & TANTRANSCO may examine the possibility of provision of under voltage relays in some of the low voltage nodes in their control areas. In the 61st OCC Meeting Regulation 4.6.1 was referred as given below:

4.6.1 Reactive Power Compensation a) Reactive power compensation and/or other facilities, shall be

provided by STUs, and Users connected to ISTS as far as possible in the low voltage systems close to the load points thereby avoiding the need for exchange of Reactive Power to/from ISTS and to maintain ISTS voltage within the specified range.

Regulation 5.2 (t) was also referred as given below: 5.2 (t) All Users, CTU & STU shall provide adequate voltage

control measures through relay as finalized by RPC, to prevent voltage collapse and shall ensure its effective application to prevent voltage collapse/cascade tripping.

It had been felt that the utilities could examine provision of under voltage relays as mandated in IEGC Regulations to control low voltages at the following 400 kV nodes: Sriperumbudur, Alamathy, Chittoor, Nellore, Mysore, Somanahalli, Kalavindapattu, Trichur & Hosur. Subsequently, the issue had also been taken up by Member Secretary I/c, SRPC with the TCC Members of State utilities vide letter dated 11th July 2011.

b) KPTCL had informed that all CEE Transmission Zones had instructed concerned Executive Engineers of TL & SS Division under their jurisdiction to maintain all capacitors in healthy condition and connected to the grid positively during low voltage condition.

c) In the 68th OCC meeting, concern had been expressed about low voltage situation in Chennai area. TN informed that capacitor bank installation in Chennai area was under execution and was expected to be ready by March-2012. DGM, SRLDC said that while high voltage conditions were prevalent in S1 area, low voltage conditions were prevalent in S2 area. MS I/c said that during the current financial year to date there had been no addition to capacitor bank installation in the region. He urged the constituents to undertake capacitor installation programme to improve the voltage profile. KPTCL informed that laying of 220 kV cables in Bangalore had resulted in some improvement of the voltage.

d) In the 69th OCC meeting, Concerns were raised by SRLDC over increasing demand in Karnataka and also low voltage situation (at some times below 380 kV) in Bangalore. Karnataka attributed low voltage problem on certain days due to non-availability of 600 MW UPCL unit. TN informed that

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capacitor bank works were likely to be completed by April-2012. It also opined that system studies at 400 kV for compensation may not pin point the problems in distribution network and said that exclusive studies were required at 11 and 33 kV level to address the issue.

8.5 Absorption / Injection of VARs by Generators


a) Hon’ble CERC Order dated 23.12.2009 merited attention in this regard. It was stated in the Order that all agencies need to provide required reactive compensation avoiding the need for exchange of reactive power to/from ISTS and maintain ISTS voltage within specific range.

b) SRLDC had said that the performance of generators was being monitored by SRLDC. MVAR absorption / injection of generating stations/units located close to high voltage nodes for 18th March 2012 and 25th March 2012 were presented (Annexure - XXV). Nearly all the units were not

absorbing VARs upto the desired levels. In the study, only 30% MVAR capacity had been considered which could be around 40% as per the capability curves. The chart showed that Vijayawada Unit 7, Ramagundam STPS (Unit 4, 5, 6 & 7), Kakatiya, and Simhadri (Unit 3) could absorb more MVAR.

c) In the 68th OCC meeting, MS I/c, SRPC had requested the concerned SLDCs to take up the issues with the generators to respond as per grid requirements within the margins available to them.

d) In the 69th OCC meeting SRLDC had informed that it planned to conduct Mock Exercise for analysis of MVAR absorption/injection capability of individual generating units of ISGS in SR on sample basis. The units would be subjected to for measuring MVAR absorption at different MW levels. The Mock Exercise was planned in the last week of March 2012. The Members expressed difficulty in conducting such Mock Exercise during the regional peak months of March and April. It was therefore decided to reschedule this exercise after June-2012.

e) In the 69th OCC meeting, SRLDC had stated that despite raising this issue in the last few OCC meetings not much progress was observed. The reasons for non-absorption MVARs by generating units was not being informed or known. Many of the generating units had not fully utilized their capabilities of MVAR absorption for maintaining the voltage at around 400 KV. Further, it was also pointed out that quite some time ago, NTPC Ramagundam had been requested to change the taps and yet no information on its implementation was received. MS i/c suggested a special meeting on MVAR absorption by Generating units with generators, IPPs and constituents be held. It was agreed to conduct this meeting after conclusion of the 70th OCC meeting on 9th April-2012. It was also agreed that SRLDC would circulate some of the specific instances when the voltage profile was above IEGC range and adequate margin for MVAR absorption by major generating units was available.

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8.5.2 A Special Meeting on MVAR absorption was held immediately after the

conclusion of this OCC meeting with participation from Generating

Companies. SRLDC had circulated some of the specific instances when

the voltage profile was above IEGC specified range and adequate margin

for MVAR absorption by major generating units was available. NTPC

pointed out that power factor was also to be considered while deciding the

MVAR absorption limits of the generator. It was expressed by the

generators that various reasons such as heating of the windings, and

stability factor were limiting MVAR absorption by the generating units.

Subsequently SRPC had addressed a letter to the generators requesting

them to furnish the data also containing the limiting factors, which would be

discussed after conclusion of the 71st OCC Meeting (Annexure - XXVI).

8.6 Requirement of reactor at Vemagiri Complex

It was noted that the requirement of reactor at Vemagiri Complex was deliberated in

earlier Standing Committee Meetings and APTRANSCO was to take a call on this

issue. There had been no further developments communicated by APTRANSCO.

There were some issues with GTs in the Complex with secondary voltage as 420 kV

and the area was facing high voltage.

9. INSTALLATION OF SHUNT CAPACITORS

The progress of installation of HT shunt capacitors was reviewed and the details are

listed below:

(Figures in MVAR) Sl. No.

Description APTRANSCO KPTCL KSEB TNEB Total

1. Total Installed as on 31.03.2011

6593.4 4573.96 995 3947.5 16019.86

2. Carryover of 2010-11 55 122.314

10

101

288.314

3. Capacitors installed during March 2012

0 0 0 0 0.0

4. Total Cumulative installed for 2011 -12

0 48.16 0 0 48.16

10. NOTIFIED POWER CUTS

10.1 It was noted that power cuts for HT consumers in TN had been increased from 20%

to 40% w.e.f. 27th February 2012 (Details in Item No. 4 above).

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10.2 MS i/c SRPC requested that details of Notified power cuts and load shedding be

segregated and informed to SRPC Secretariat/CEA in a timely manner by written

communication to appraise MoP/GoI appropriately.

11. OTHER ISSUES

11.1 Crisis Management Plan/Black Start Procedures

11.1.1 The format to furnish the information regarding Crisis Management Plan was

furnished in the 44th OCC Minutes. The information is required to be sent to

the following E-mail addresses:

i) [email protected]

ii) [email protected]

iii) [email protected]

11.1.2 In the 64th OCC meeting, MS i/c, SRPC had informed about the letter dated 27th

September 2011 received from CEA wherein it was informed that the CMP was

being monitored at the highest level. For this purpose, various

utilities/organizations were required to submit Quarterly Reports through

Regional Power Committee (RPCs) / National Load Despatch Centers (NLDC).

The proforma for the report of mock drills indicating the scenario of mock drill

situation, chronological order of events logged, observations on effectiveness of

mock drill and recommendations/suggestions on the observations etc. had

already been communicated. It was also indicated that CMP be made

applicable to private players of power sector. Concern over only few utilities

submitting the report had been expressed. RPCs had been requested to advise

the utilities / constituents to submit the quarterly reports regularly.

11.1.3 SRLDC had informed that the requirement of synchronising facility at black start

restoration critical substations (Annexure - XXVII) had been discussed and

followed up in various OCC/Protection Committee Meetings. KPTCL informed

that all critical 220 KV substations are having synchronization facility except

Hubli, this will be taken up in R & M works.

11.1.4 The updated status of mock drill of black start procedure furnished by SRLDC is

at Annexure - XXVIII. KPCL was requested to furnish mock drill schedule for

2012

mailto:[email protected]



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11.2 Normative Vs. average actual ex-bus generation

DGM, SRLDC also presented the details of normative and average actual ex bus

generation in respect of ISGS during the month of March 2012 (Annexure - XXIX).

It was noted that in respect of Ramagundam, Simhadri Stg II and Talcher Stage II

the actual DC was more than the normative DC. The actual ex-bus generation in

respect of Ramagundam, NLC (TS-II Stage-I & II, TS-I Expn.) and Simhadri Stage II

was also more than the actual DC.

11.3 Utilisation of inter-regional links

DGM, SRLDC also presented details of the utilization of inter-regional links for the

month of March 2012. (Annexure - XXX).

11.4 Tripping details


a) SRLDC had expressed serious concern since the information regarding tripping details with relay indications was awaited from nearly all the constituents. He had said that the entities should furnish the preliminary report on ‘events’ in compliance of IEGC Regulation, 5.9.6(a). Detailed report along with necessary information as mandated by IEGC should be followed. MS I/c, SRPC had said that as stressed earlier information needed to be continuously provided to SRLDC/SLDCs as they had to coordinate a number of activities and plan load generation balance in real time. If concrete information was not provided it would affect in taking optimal decisions in the interest of the grid. The issue was being followed up both in Protection & Operation Sub-Committee meetings but there was no noticeable improvement. Constituents should identify and implement a methodology so that the requisite information was available to the RLDC/RPC. SRPC was also apprised of the requirement in the recently concluded meeting held on 23rd December 2011.

b) SRLDC had said that as informed in the earlier meeting, they would like to have the ownership details of bays at various stations. POWERGRID had since then submitted the details to SRLDC.

c) In the 68th OCC meeting, constituents were requested by SRLDC for submission of detailed tripping events for further analysis and prevention of its repetitions. It was decided to discuss these things further in the forthcoming PCC meeting.

11.4.2 The status of pending information for the month of March 2012 is enclosed as

Annexure - XXXI.

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11.5 Wind Generation

DGM, SRLDC presented the day-wise Wind Generation pattern in respect of

Karnataka & Tamil Nadu for the period between 1st and 31st March 2012. Wind

generation in Tamil Nadu had varied between 33.713 MU (8th March 2012) to 1.539

MU (28th March 2012). Wind generation in Karnataka had varied between 11.021

MU (30th March 2012) to 1.208 MU (20th March 2012). Details are furnished in

Annexure - XXXII.

11.6 Drawal Extremes

11.6.1 In the earlier meetings the following was noted:

a) In the 68th OCC, TN had suggested that data regarding Drawal Extremes displayed by SRLDC should also include details of frequency and schedule etc. so as to portray the correct picture. DGM, SRLDC said that drastic change in flows upto 790 MW during changeover took place on 400 KV GTY-NLM and GTY-HDY lines. TN said that any under-drawal at high frequency was also harmful to grid stability and should be treated on similar lines of over-drawal at lower frequency. TN therefore suggested that messages could be issued for under-drawal at high frequency also. SRLDC assured that they would look into this issue.

b) In the 69th OCC meeting, SRLDC informed that due to very high quantum of load shedding in Tamil Nadu on account of deficit, the peak recorded was less than last year. TN informed that during February- 2011, while the load shedding was 403 MU, in February-2012 it was as high as 1535 MU. SRLDC further informed that from 2nd April-2012 onwards, as per the revised IEGC limits, the frequency on the lower limit stands increased to 49.7 Hz. MS i/c said that at any point of time, grid discipline schedule would need to be maintained by adhering to the schedule. He also added there may be a need for issue of messages for under drawal at high frequency as discussed in earlier OCC Meeting.

11.6.2 DGM, SRLDC presented the statement of Drawal Extremes for the month of

March 2012. The maximum till date are given in the table below:

State Extremes March 2012 Extremes till date

Maximum Minimum Maximum Minimum

MW Date Time Block

MW Date Time Block

MW Month MW Month

AP 3131 24.03.012 62 1314 11.3.2012 73 4005 Aug-08 -1280 Aug-06

KAR 1981 08.03.2012 61 854 12.3.2012 33 2722 Sep-10 -947 Sep-09

KER 1615 02.03.2012 76 932 08.03.2012 44 1785 Jan-11 -610 Oct-07

TN 3235 17.03.2012 73 1801 24.03.2012 61 4315 May-11 -100 Oct-03

PUDU 300 09.03.2012 76 193 09.03.2012 17 309 Sep-11 8 Dec-11

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Andhra Pradesh, Karnataka, Kerala, Tamil Nadu and Pondicherry had variations

(maximum of about 1817 MW, 1127 MW, 683 MW, 1434 MW and 107 MW

respectively.

11.7 400 kV UPCL-Shanthigram DC line

KPTCL informed that out of 529 locations, 503 stubs had been concreted,

480 towers erected and 247.19 ckm spans stringing completed on 400 kV UPCL-

Shanthigram DC line.

11.8 Load shedding details & web based PSP system utility

It was noted in earlier OCC Meetings, that the hourly load shedding details should

be furnished online by the State SLDCs before 3 ‘O’ clock in respect of the previous

day through web. SRLDC had also requested the constituents to furnish the other

details through web based PSP system utility of SRLDC. For any assistance /

clarifications, OS department of SRLDC could be approached.

11.9 Monthly Time drift report receipt status

Constituents were requested to furnish the Time Drift Report regularly to SRLDC.

The status of Monthly Time drift report presented by SRLDC is given below:

Utility Status

Andhra Pradesh No station is sending

Karnataka Nelamangala & Raichur only sending.

Tamil Nadu Only Gummidipoondi, Hosur, Kuzhithurai sending.

Puducherry Sending

ISG Stations

NLC - TS-II Not regular

NPCIL - MAPS Not sending

11.10 ATC / TTC computations

The following was noted in the earlier meetings:

a) SRLDC had pointed out that ATC / TTC computations were to be furnished by State utilities. LGBR for the next four months was needed to be furnished by all the constituents before 5th of every month for the purpose of ATC computations.

b) In the 68th OCC meeting GM, SRLDC said that a workshop on “Available Transfer Capability (ATC) in Indian Context” was scheduled to be organized on 24.02.2012 at SRLDC, Bangalore and requested participation. DGM, SRLDC said that in future SRLDC would be requiring LGBR for the next five months instead of four months at present.

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c) In the 69th OCC meeting, the efforts of SRLDC in conducting a workshop on ATC on 24th February, 2012 were appreciated. It was noted that KSEB had addressed a letter dated 5th March 2012 stressing the need for transparency in corridor availability for Day Ahead Transmission through PX. They had added that lack of knowledge on corridor availability had caused uncertainty in availability of power. In that meeting, SRLDC had reiterated their constraint in making available ATC for day ahead transaction through Power Exchange in their website.

11.11 Mock Exercise for implementation of RRF


a) In the 64th OCC Meeting, SRLDC had informed that Hon’ble CERC had conducted a Workshop on 10th October 2011 at Bangalore regarding implementation of RRF mechanism. It was noted that CERC had directed to start mock exercise for the implementation of RRF w.e.f. 1st July 2011. SRLDC had taken up the issue with beneficiaries vide letter dated 5th July 2011 requesting them to make necessary arrangements. Following action was to be initiated by the States:

i) List of the wind farms and solar farms eligible for RRF provision.

ii) Details of contracts along with contracted price to be furnished to the concerned RLDC/RPC through the respective SLDC

iii) Forecasting data for wind & solar generation to be furnished to the concerned SLDC/RLDC/RPC

iv) 15 Minute block-wise data of schedule and actual generation from wind farms & solar farms as recorded in the SEMs on weekly basis to be furnished to the concerned SLDC/RLDC/RPC

v) Solar generators may be advised to give availability of the generator, weather forecasting, solar insolation, season and normal solar generation curve etc to the concerned RLDC for vetting of the generation schedules

vi) Furnish details of nodal developer who shall be responsible for coordinating the collective capacity on behalf of the group of developers on issues like SCADA, metering, scheduling, UI charges, RRF, forecasting data to the concerned SLDC/RLDC/RPC

vii) States to identify nodal officer for coordinating on the above matters.

b) It was noted that SRLDC had informed in the earlier meetings, that Hon’ble Commission was viewing the implementation of the RRF mechanism seriously. As informed, it had also conducted a Workshop at Southern Region on 10th October 2011. SLDCs were the nodal / focal points for collecting the information in the States. Constituent states had been requested to furnish the relevant information to SRLDC/SRPC Secretariat. DGM, SRLDC had informed that a meeting was also scheduled to be held in this regard in New Delhi on 13th January 2012.

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The hearing before Hon’ble CERC was scheduled to be held on 24th January 2012.

c) MS i/c, SRPC had suggested that the process for furnishing the information could be initiated. The issue had also been taken up at TCC/SRPC forums. In the 67th meeting, it was noted that Hon’ble CERC had issued Orders in respect of Suo Motu Petition No.209 of 2011 for submission of data by SLDCs to NLDC by 15th December 2011.

11.11.2 Constituents were requested to expedite submission of details.

11.12 Weekly SEM Data Receipt Status

SRLDC informed about the delay of receipt of Weekly SEM data as given below:

Andhra Pradesh Karnataka SEPL Tamil Nadu

Station No. of

occasions Station

No. of occasions

Station No. of

occasions Station

No. of occasions

KSTPS 1 Bellary 1 Simhapuri 1 SV Chatram 2

Malkaram 1 Konaje 1 Alamathy 1

Ragulapadu 1 BTPS 1 Acharapakkam 1

Arni 1

SEPL Kuzhithurai 1

Simhapuri 1 S.P. Koil 1

Tiruvalam 1

SV Chatram 1

11.13 LC for UI payment

SRLDC informed that the following utilities had yet to open LC for UI payment

delays as given below:

Utility LC amount (` Crores)

Default for the year

Tamil Nadu 32.84

The concerned utility was requested to expedite opening of LC. TN was also

requested to settle the outstanding interest amount due to delayed UI payment.

12. SCHEDULING OF VALLUR JV

In the 69th OCC meeting, TN requested that till such decision of CEA/MOP in

response to SRPC’s letter was received, the scheduling of Vallur JV could be carried

out by SRLDC. MS i/c suggested that till the settlement of the issues, scheduling of

Vallur JV could be carried out by SRLDC based on request letter from TN. SRLDC

informed that as a temporary measure they would agree to carry out the scheduling of

Vallur, till TANTRANSCO equipped itself for the same. TANTRANSCO subsequently

submitted the request letter in this regard to SRLDC.

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13. MAINTENANCE SCHEDULE OF GENERATING UNITS

13.1 Reviewed & updated Outage Plan for the year 2012-13 is available at location

(http://www.srpc.kar.nic.in/website/2012/operation/Outage%20Plan%202012-13.pdf)

on SRPC website.

13.2 Details of generating units under shut down (forced as well as planned) during

March 2012 are enclosed as Annexure - XXXIII.

14. SHUT DOWN PROGRAMME OF CENTRAL GENERATING STATIONS

It had been noted in the earlier meetings that as per IEGC Provisions, RPCs are to

submit quarterly, half yearly reports to the Hon’ble Commission indicating deviations in

outages from the plan along with reasons. SRPC said that the reasons for outage

deviations also needed to be communicated to SRPC Secretariat.

15. MAINTENANCE OF LINES AND ICTs COMPLETED IN MARCH 2012

The planned maintenance of elements carried out by PGCIL/NLC during the month of

March 2012 is furnished at Annexure – XXXIV.

16. SHUT DOWN PROGRAMME OF LINES AND ICTs PROPOSED

16.1 The shutdowns of the ISTS system approved by the OCC are given in Annexure –

XXXV.

16.2 Planned shutdowns of 400 kV transmission elements of State Sector

In the earlier OCC meetings it had been recommended that the planned shutdowns

of 400 kV transmission elements of State Sector also needed to be approved

through OCC. State transmission utilities had been requested to furnish the planned

shutdowns of 400 kV transmission elements in their system for the year 2011-12.

17. CAPACITY ADDITION IN SOUTHERN REGION

It had been decided in the SRPC meetings that the constituents would furnish the

status on upcoming Generating Schemes, since SRP Committee needed to be kept

informed of the likely capacity additions. SRPC requested the constituents to furnish

on a regular basis, the updated information on capacity additions including the IPPs,

to help apprise SRPC appropriately.

http://www.srpc.kar.nic.in/website/2012/operation/Outage%20Plan%202012-13.pdf

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18. REVIEW OF PERFORMANCE OF ULDC SCHEME

18.1 DGM, SRLDC informed about the status of pending field inputs (Annexure -

XXXVI). He added that in the 18th SRPC Meeting, it was noted that all the

constituents had assured to expedite and complete the pending works. There were

still 564 inputs pending as on 4th April 2012. As the constituents were aware

SRLDC had approached Hon’ble CERC through a Petition regarding establishment

& maintenance of data and communication facilities and the same had been

admitted. The following was the status intimated by SRLDC:

Standby Data Channel Status

Non-availability of standby data channels at the following stations:

AP: LANCO, Warangal

Karnataka: Hiriyur, Nelamangala

Kerala: Kochi, Palakkadu, Trivandrum

TN: Kudankulam, NLY TS 2Exp, NTECL Vallur

Bhadravati, Talcher RCI Voice Communication status (PUNCOM)

Non-availability of voice communication at the following stations:

AP: Nellore, Gazuwaka

Karnataka: Hassan, Hiriyur, Kaiga, Kolar HVAC, Kolar HVDC, Mysore, Munirabad, Narendra

Kerala: Kochi, NTPC Kayamkulam, Palakkadu, Trivandrum

TN: Kalivathnapattu, MAPS, Pugalur, NLC TS 1 Expansion, NLC ST2, NLY TS 2 Expan, NTECL Vallur

Puducherry

Bhadravathi, Talcher HVDC

Internet communication

Reliable / Dedicated internet communication for system operation-Status of confirmation.

18.2 In the 68th OCC meeting, MS i/c SRPC had said that real time data terminal also

needed to be available at SRPC Secretariat as per the regulations.

18.3 In the 69th OCC meeting, AP and Tamil Nadu pointed out that hotline facility with

SRLDC was not functional for quite some period. SRLDC replied that it would

address this problem and requested the constituents to take up the issue with the

telecom operator at their end also.

Minutes of the 70th


44

19. VOTE OF THANKS

MS i/c, SRPC thanked the Members for their active participation in the meeting.

20. DATE & VENUE OF THE NEXT MEETING

The schedule for next OCC Meeting is as follows:

Meeting : 71st OCC of SRPC

Date : 11.05.2012 (Friday)

Time : 10:30 Hours

Venue : SRPC, Bangalore

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