Mailing list:

1 Director (Operation)Maharashtra State Elect.

Trans. Co.Ltd, / Chairman,TCC,WRPC Prakash Ganga, Plot No. C-19, E-Block, Bandra Kurla Complex, Bandra (East), Mumbai.-400051

2 Chief Engineer (GM), Central Electricity Authority, GM Division, Sewa Bhavan, R.K. Puram, New Delhi.-110 066

3

Chief Engineer (Commercial), Chhattisgarh State Power Dist. Co.Ltd., 4th Floor, Vidyut Sewa Bhawan, Danganiya, Raipur.-492 013

4 Chief Engineer (O&M Gen.) Chhattisgarh State Power Gen. Co.Ltd., P.O.: Sunder Nagar, Danganiya, Raipur.-492 013

5 Executive Director (Gen.),

Gujarat State Electricity Corp. Ltd, Sardar Patel, Vidyut Bhawan Race Course, Vadodara.-390 007

6 Addl.Chief Engineer (R & C), Gujarat Energy Transmission Corp. Ltd, Sardar Patel, Vidyut Bhawan, Race Course, Vadodara.-390 007

7 Chief Engineer (Operation),

Uttar Gujarat Vij Company Ltd., Corporate Office, Visnagar Road, Mehsana – 384 001.(North Gujarat).

8 Executive Director (O&M-Gen), M.P.Power Generation Company Ltd., Shakti Bhavan Vidyut Nagar, Rampur, Jabalpur.-482 008

9 Director (Operation), Maharashtra State Electricity Gen. Co. Ltd., Prakashgad, Plot No G-9, Bandra (East), Mumbai.-400051

10 Director (Operation), Maharashtra State Elect. Dist. Co. Ltd., Prakashgad, Plot No G-9, Bandra (East), Mumbai.-400051

11 Executive Engineer, Electricity Department, Power House, Bldg. No.2, Nani Daman 396 210

12 Executive Engineer, Electricity Department, DNH Electricity Department, 66 kV Amli Road, Silvasa 396 230

13 Regional Executive Director,

NTPC Ltd ,WRHQ, Samrudhhi Venture Park , 2nd floor, Marol, Andheri (East), Mumbai.-400 093

14 Chief Engineer (Trans), Nuclear Power Corporation of India Ltd, 12th Floor, North Wing, Vikram Sarabhai Bhavan, Anu Shakti Nagar, Mumbai.-400 094

15 Executive Director, Powergrid Corporation of India Ltd, WRTS-I, Sampriti Nagar, Nari Ring Road, Nagpur.-440 026

16 Executive Director, Powergrid Corporation of India Ltd, WRTS-II Head Quarters, 5th Floor, Vuda Bhavan, Kareli Baug, Vadodara.-390 018

17 Vice President,

Tata Power Co. Ltd. Corporate Centre, "A" Block, 34, Sant Tukaram Marg, Carnac Bunder, Mumbai.-400 009

18 General Manager (Power), Ratnagiri Gas and Power Pvt. Ltd, RGPPL(site), P.O.Anjanwel, Taluka-Guhagar, Dist-Ratnagiri-415703

19 General Manager, Indira Sagar Power station, NHDC Office Complex, Narmada Sagar, Distt- Khandwa, Madhya Pradesh-450 119

20 Executive Director (O&M) Torrent Power, Sugen Mega Power Project Off. National Highway No.8, Taluka-Kamrej, Dist-Surat-394155

21 Associate General Manager(Business

Development),Adani Power Limited, 10 B, Sambhav Building, Judges Bungalow Road, Bodakdev, Ahmedabad – 380015, Gujarat.

22 Vice President (O&M), Jindal Power Ltd., P.O.Tamnar, Dist: Raigarh-496 107 (Chhattisgarh)

23 AVP –Power Trading & Regulatory,

GMR Energy Trading Ltd., IBC Knowledge Park 2, D-Block 9th Floor, 4/1, Bannerghatta Road, Bengaluru- 560 029, Karnataka

24 Vice President, Torrent Power Ltd, 3rd Floor, Jubilee House, Shahpur, Ahmedabad – 380001.

25 Director ( Technical & Projects), M/s.JSW Energy Ltd.,NBCC Tower, Upper Ground Floor (UGF), 15, Bhikaji Cama Place, New Delhi – 66.

CC to

1 Member (Power System), Central Electricity Authority, Sewa Bhavan, R.K. Puram, New Delhi.-110 066

2 Chairman & Managing Director, M.P. Power Trading Company Ltd, Shakti Bhavan Vidyut Nagar, Rampur, Jabalpur.-482 008

3 Managing Director,

Gujarat Urja Vikas Nigam Ltd., Sardar Patel, Vidyut Bhawan Race Course, Vadodara.-390 007

Record notes of the meeting to discuss and formulate an action plan to implement recommendations of Enquiry Committee on Grid Disturbance (30th & 31st July 2012), held on 29.11.2012 at WRLDC Mumbai.

A meeting to discuss and formulate an action plan to implement recommendations of

Enquiry Committee on Grid Disturbance (30th & 31st July 2012) was held on 29.11.2012 at

WRLDC Mumbai. The list of the participants is enclosed at Annexure-1.

Shri S.D. Taksande, Member Secretary I/c, WRPC welcomed the participants for the

meeting. He stated that the recommendations of Enquiry Committee on Grid Disturbance

(30th & 31st July 2012) headed by Shri A.S.Bakshi, Chairperson CEA were taken up for

discussions during 21st WRPC meeting held on 8th November 2012 at Raipur. During

discussion due to complexity of certain recommendations it was felt necessary to discuss and

formulate action plan to implement recommendations. Therefore a meeting was proposed on

29th November 2012 after giving due time for thought process to the utilities. Further

report/recommendations of the group formed under Shri U.G.Zalte, Chairman TCC and

Director (O) MSETCL to look into the preparedness of WR for such events was discussed in

the special meeting held on 07.09.2012. Subsequently, the final report of the group formed

under Shri U.G.Zalte was circulated to utilities. Recommendations of Shri U.G.Zalte

committee report were also put up to WRPC on the 8th Nov 2012 meeting. Committee

accepted the recommendations and also suggested to discuss implementation of these

recommendations in the proposed meeting of 29th November 2012. Accordingly today’s

meeting is convened.

He stated that he was happy to invite Shri S.G.Patki, who is working with TATA

Power and also a Chairman on CBIP committee to guide us on recommendations regarding

Z-3 setting, identification of fault vis a vis load encroachment.

Thereafter the recommendations of the ECGD (enclosed at Annexure-2) were taken

up for discussion;

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9.1.1Protection Audit:

MS, WRPC requested participants to give status on the protection audit and offer

suggestions to identify the standard procedure (criteria) for protection audit.

MSETCL representative informed that in a pilot project they have identified critical

S/S (Lonikand, Padghe) for which an order have been placed with PRDC for

protection audit and based on this experience, further course of action would be

decided. He further informed that they have an internal system of protection audit

wherein the testing engineers from one circle carry out protection audit of other circle

and almost 100% of such protection audit is being done.

GETCO representative informed they are carrying out yearly protection audit in their

system. Protection Audit of all the 132 & 220kV S/S, for the year 2008-09 was

completed and corrections in setting have been done. In the second phase contract

have been awarded to M/s Voltech Engineers Pvt. Ltd., wherein condition monitoring

of the CTs & PTs have also been envisaged along with protection audit of all 132kV

& 220kV S/S.

MPPTCL representative informed that an internal group comprising of members from

SLDC, GENCO and TRANSCO has already been formed and the protection audit

would be completed by 31.12.2012.

NTPC representative informed that they are carrying out internal protection audit in

their system.

CSPTCL representative informed that they would be starting the protection audit in

their system shortly.

MS WRPC informed that PGCIL have carried out Protection audit in NR, along with

protection audit of Bina S/S in WR. He further requested utilities of WR to submit the

protection audit reports carried out so far in their system to WRPC secretariat.

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Shri S.G. Patki, TPCL stated that, it is important to check the configuration of the

protective relaying system (especially the modern numerical protection relaying

schemes). A list of settings that are required to be disabled shall be checked, since

some of the factory default settings are not required to be kept in operation.

After deliberations following minimum set of protection audit scope was identified

and additional requirements if any may be incorporated in the scope of protection

audit:

(i) Relay setting calculations and verification of these calculations with

the relay settings adopted.

Special attention shall be given to Z-3 (permissive over reach & under

reach) settings, PSB, OST and zero sequence compensation.

(ii) Type of carrier availability.

(iii) Uniformity in adopting the settings.

(iv) Checking healthiness and quality of S/S DC system (including

healthiness of batteries) and earth leakages.

(v) Checking time synchronisation, readiness and recordings of DRs SERs

and their storage facilities.

(vi) GPS availability and functionality.

(vii) Readiness of synchronising trolley.

(viii) Check whether irrelevant features of the numerical relay are disabled

or not.

(ix) Multiple earthing of CTs

MS WRPC stated that following approaches were proposed during the 21st WRPC

meeting for carrying protection Audit:

i. A revolving group of members from utilities in WR, WRPC & WRLDC may

be formed who will carry out the protection audit in WR.

ii. Utilities may carry out protection audit of protection systems in their

jurisdiction on their own and the same would be vetted by WRPC.

iii. Utilities may approach outside agencies such as CPRI, PRDC etc. for carrying

out third party protection audit.

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9.1.2: Zone-3 settings:

Special invitee Shri S.G. Patki, TPCL gave a presentation on the Zone-3 (Paper on

Application of Overreaching Distance Relays is available on WRPC website

→ Meetings→Protection Committee→Minutes ), wherein he discussed following

issues:

(i) Susceptibility of overreaching distance zones to undesirable operation

(ii) Zone Characteristics Impacting Loadability

(iii) Variations in Zone Positioning

a. Mho characteristic angle adjustment - maintaining a given mho circle

b. Offsetting of mho characteristics

(iv) Variations in Zone Shape

a. Lens characteristic

b. Rectangular (Quadrilateral) characteristic

(v) Supervision of Zone tripping

a. Use of blinders

b. Use of load encroachment characteristics

(vi) Means to prevent tripping on load:

a. Shaping the characteristics & load encroachment blocking

b. Using ground directional overcurrent (67N) instead of Z2 in pilot schemes

c. Maximum sensitivity angle (characteristic or torque angle) Considerations

(vii) Power Swings and Their Impact on The Power System

a. Impedances Seen by Distance Relays During Power Swings

b. Effect of Power Swings on Distance Relays

c. Means to Prevent Tripping on Power Swings.

(viii) Power-Swing Blocking and Tripping Functions

a. Power-Swing Blocking, Tripping Principles & Functions and Additional

Considerations

b. Distance Protection Requirements During OOS Conditions

c. Power Swing Protection During Single Pole Open Conditions

d. Three-Phase Faults Following Power Swings

As regards to Power Swing Blocking (PSB), MS WRPC stated that there has been

discussions on the PSB and there is a thought that, on detection of power swing the Z-2 &

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Z-3 tripping shall be blocked and if the power swing enters in Z-1 the relay shall not be

blocked from tripping, since it has been felt that the power swing in Z-1 is generally of severe

nature and the two systems connected by the tie are going out of synchronization.

MSETCL representative informed that on detection of power swing, the Distance

Protection Scheme (DPS) is blocked in Z-1, Z-2 and Z-3 for 2 secs. The PSB is configured

such that if a fault is detected during this blocking period the relay would initiate a trip

command.

NTPC representative stated that the function of PSB feature is to block the DPS, since

a power swing is not a fault and therefore all trippings under stable power swing detection

should be blocked irrespective of it entering in any zone. The blocking time of 2 sec has been

arrived at, by considering the prominent existence of interregional oscillations of 0.5Hz. He

further stated that to guard against a possibility of inter area loss of synchronism, out of step

relaying must be employed, in such corridors.

Shri S.G. Patki, TPCL suggested that, positioning of power swing detecting blinders

play an important role in efficient detection of stable power swing. Therefore the positioning

of blinders be done, such that the power swing could be detected at the verge of entering in

the Z-3.

CSPTCL representative suggested that the PS and load encroachment blocking be

enabled by detecting the absence of zero sequence component in the PS and load

encroachment, thereby the PSB and load encroachment blocking function would be able to

discriminate between the fault and PS & load encroachment. Based on this algorithm, the

relay would decide whether to block the trippings or not on power swings and load

encroachment.

As regards to adoption of Z-3 settings, NTPC representative stated that in most of the

cases the Z-3 line impedance calculation show that the relay would be reaching the next

voltage level (over reaching) and therefore the setting in most of the cases has to be set less

than the Z-3 line impedance. Hence there is a least chance of load encroachment in Z-3.

Shri S.G. Patki, TPCL informed that, the main consideration for identification of fault

and load encroachment in Z-3 would be the load angles. The load angle generally lies

between -20 to +20degrees and the line angle is far greater than the load angle, therefore

these can be differentiated by placing blinders for the angle detection in a relay with

rectangular characteristics.

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As per the recent studies and analysis of data of PMU recordings during the last GD,

it was concluded by WRLDC that the new modes of oscillations of 0.3 Hz having significant

magnitude and inadequate damping were present during the GD. Therefore the time for PSB

needs to be revisited by carrying out accurate studies and proper vetting of the same.

As regards to load encroachment in Z-3, the crucial factor which has impact on this

phenomenon is the consideration of Arc Resistance of the fault (depends on the fault level,

voltage and is determined empirically), Tower footing resistance (depends on soil chemistry)

and zero sequence compensation during the calculation of setting for Z-3. Since Z-3 in a

distance protection scheme is a backup protection, the adoption of this setting need to be

conservative and therefore any overreaching in Z-3 should be avoided. Though there is a

complexity in grading a Directional Earth Fault (DEF) protection (which is available in

almost all the numerical relays) in a very large system, DEF protection could be a very good

solution to high resistive faults on adoption of conservative settings for Z-3.

MS WRPC stated that Z-3 settings shall be adopted judiciously by giving due

considerations to the above discussions.

9.1.3: Application of PMUs & SPS:

GM WRLDC intimated that as a pilot project PMUs have been installed at following

locations:

(i) Bhadravati

(ii) Raipur

(iii) Jabalpur

(iv) Itarsi

The data from these PMUs is being studied and analysed by WRLDC. The unified

WAMS project is being implemented by CTU/PGCIL and after implementation of

this project there would be significant increase in population of PMUs in WR. This

data can then be analysed and WAMS based Special Protection System (SPS) for

critical transmission elements could be designed.

MS WRPC informed that following Islanding schemes are operational in WR:

(i) Mumbai islanding scheme for TPC-REL.

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(ii) Uran Gas Power Plant islanding scheme in Maharashtra.

(iii) Ahmedabad Torrent Power islanding scheme in Gujarat.

He further informed that following SPSs are under consideration and would be

finalised shortly:

(i) SPS for APL-Mahendragarh HVDC.

(ii) Korba 220kV system in Chattisgarh.

(iii) SPS for Sugen-Vapi system till shifting of DD & DNH loads from GETCO

system to CTU system.

He requested SLDCs of Gujarat, MP and Maharashtra to design islanding schemes for

big cities in WR such as Vadodara, Bhopal, Nagpur etc..,

9.1.4: Independent audit of time synchronisation of DRs, ELs and PMU:

As discussed at S.No.9.1.1.

9.2.1: Tightening of frequency band : Action by POSOCO

9.2.2: Review of UI mechanism : Action by POSOCO

9.3: Under frequency and df/dt schemes:

MS WRPC informed that U.G.Zalte Committee have recommended the quantum of

load shedding and settings for under frequency & df/dt load shedding schemes.

SE (O) stated that the quantum of load relief already implemented by the utilities of

WR is more than the recommended relief in the U.G.Zalte committee report.

9. 4: Implement provisions of IEGC with regard to governor action: Action by

POSOCO

9.5.1: Detailed procedure to address inconsistency in congestion regulation:

Action by POSOCO

9.5.2: Real time security desk capable of carring out TTC calculations: Action by

POSOCO

9.6: Outage planning of inter-state and inter-regional transmission elements :

MS WRPC informed that this recommendation is being implemented in the OCC of

WRPC.

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9.7:Planning and installation of adequate static and dynamic reactive power

compensators : MS WRPC requested STUs and CTU to submit the above details.

9.8:Action by MoP

9.9.1:Action by POSOCO

9.9.2:Audit of HVDC,TCSC,SVC & PSS.

SE (O) stated that, PSS tuning of 23 generators have already been carried out in WR

and PSS tuning of Gandhinagar TPS is pending under the PSS pilot project in WR. In

the last study group meeting it was decided that utilities would carry out PSS tuning

on their own and WRPC and IIT-B would extend support to these utilities.

9.9.3:Action by CTU/POSOCO

9.10.1:Action by CTU

9.10.2:Voltage collapse prediction, sensing global power system conditions

derived from local measurements:

MS WRPC informed that, WRLDC has already taken up a Pilot project with M/s E-

berle and installed Voltage Collapse Prediction relay at 400kV Boisar (PG) S/S and

its output is under observation. In view of the seriousness of the requirement after the

grid disturbances, the proposal can be extended to other important substations. Few

S/Ss of NTPC/POWERGRID/States would be identified for installation of these

relays through own funding by the respective agencies. WRLDC would also file a

petition with Hon’ble CERC for approving funding of the scheme from Addl. UI/CAP

fund. In case non approval by Hon’ble CERC, the funding would be done by

respective agencies in whose S/S the relays are to be installed. He further informed

that the above relays were earlier agreed to be procured under PSDF. However due to

uncertainty on the PSDF issue and in view of the recommendation of Enquiry

Committee the same is suggested to be procured by individual utilities as indicated by

WRLDC .

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9.11:Action by POSOCO

9.12:Islanding schemes

As discussed under 9.1.3.

9.13.1:Action by GoI

9.13.2:Action by GoI

9.14:Planning & strengthening of Intra-State transmission system: Action by

STUs

9.15.1:Action by CEA

9.15.2:Communication network: Action by CTU & STUs

9.15.3:Uninterupped power supply to S/S SCADA equipments

9.15.4:Existing generating stations or transmission elements without telemetry

facility: Action by RPCs POSOCO

9.16: Unit start ups & Start up Procedures: Action by CEA, Generating utilities

& RLDC.

9.17: Action by CEA

9.18:Reinforcement of system study groups: Action by CEA,CTU & STU.

9.19: Action by MoP, CEA

9.20:Reliable telecom network : Action by CTU STUs.

MS WRPC stated that NTPC have reservations on the following recommendations of

Shri. U.G.Zalte Group and therefore NTPC may explain their views on these

recommendations

A. Defense Mechanism for high frequency

Following units were identified for automatic tripping at high frequency (51.5 Hz) to help

in arresting the rise of frequency:

1. KSTPS-7 (500 MW) 2.VSTPS-7 (500 MW) 3. CGPL-10 (830 MW)

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NTPC vide ref:01:CD:708C dated 17th Nov 2012 (copy enclosed at Annexure-3), have

expressed followings views on the above recommendation.

The issue of high frequency tripping has been examined by technical experts at NTPC

and it is felt that high frequency tripping is not required. It is intended that a generating

unit should be capable of surviving even a 100% load throw off, without tripping. On

100% load loss a reheat steam unit will experience a maximum transient speed rise of 8%

(IEC-45) and a steady state speed rise of 4-5% (3-6% as per IEGC). Even during the

transient speed rise, the unit should not trip and hence the over-speed tripping (a safety

feature) is arranged at or above 110%. Hence specific tripping at 51.5 Hz is not

appropriate. Any additional modification in the setting of machines will have to be

examined, if same is required as per OEMs overall philosophy. In the grid of 40,000 MW,

identification of units should be done equitably. Only NTPC units should not be singled

out for the said issue.

NTPC representative made following points:

i. Rise in frequency is not a situation which warrants drastic action to trip units to

reduce generation, as it cannot cause a collapse of the power system, unlike the

situation of low frequency. High frequency can be easily controlled by controlling the

generation. From the system point of view higher than nominal frequency is not

considered dangerous/harmful to the system and system equipments.

ii. At frequency varying from 51.0-51.5Hz, all thermal machines in the system

(except the older mechanically governed machines), including CCGT units will start

unloading as per the droop characteristics. Assuming a governor droop of 5%, this

would result in reduction of 20% of the generation capacity in service, for a frequency

rise of 0.5Hz, above this threshold. This unloading feature can neither be offset

beyond 51.5Hz nor can it be prevented, being a safety feature.

iii. CCGT units at Jhanor start unloading at 51.2Hz and are wired to trip at 51.7Hz.

Kawas CCGT units start unloading at 51.2Hz as per its governor droop.

iv. In the event of such a frequency rise it is likely that some generators trip during

the re-adjustment of their process, inadvertently. During the said disturbance also

such tripping had taken place. If the total generation available after such intended and

inadvertent unit outages fall short of the load, the system will be facing a far more

disastrous frequency decline situation.

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MS WRPC stated that, the tripping of units envisaged in the report is a rarest of rare

event and the probability of occurrence of such an event is very low. Further, the

above trippings have not been envisaged for a gradual frequency rise, but for the

event of separation of WR from NR, ER & NER. Under such circumstance as

observed during the 31.07.12 GD, the WR frequency would rise in the time frame of

around 3-5mins and therefore it may be noted that governor action would not respond

quickly and adequately for obtaining the desired generation reduction. Further, though

high frequency does not have adverse impact on the system/system equipments, there

would be a significant rise in over voltages in some of the pockets and power inrush

through critical corridors, leading to tripping of transmission elements and thereby

jeopardising the grid security. Hence a quick and adequate response in generation

shedding is required under such disturbances. The tripping of above units have been

arrived by giving due considerations to the above facts and system studies carried out

by WRLDC. Also it may be noted that the above trippings have been envisaged after

resorting to all the measures required to be undertaken under such circumstances by

WRLDC in the real time grid management. Therefore NTPC should not feel that the

above units have been singled out.

However, NTPC representative expressed that the proposed tripping of generating

units at 51.5Hz may not be appropriate and hence need not be adopted.

B. SPS for Agra -Gwalior

Committee recommended following Units in WR were to be considered for backing

down to the tune of 500 MW in the event of tripping of Agra-Gwalior lines and

Bina-Gwalior lines :

i) Korba, Sipat, Vindhyachal STPS to control power flow towards ER

ii) CGPL & SSP* to control power flow in Zerda-Bhinmal-Kankroli lines

iii) JP Bina to control power flow in Bina-Mehgaon-Gwalior lines &

iv) ISP* to control power flow in Badod-Kota-modak lines

*Since SSP and ISP are hydro units and may not be always available, Committee

recommended backing down at Korba, Sipat, Vindhyachal, CGPL and JP Bina.

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NTPC representative stated that none of the stations named in the SPS action list have

any transaction to NR and hence consumption from these stations is within Western

region only. Hence an SPS is being planned for the said lines, the same should not

involve the NTPC stations mentioned. The stations with inter-regional transactions on

the said line may be considered under the SPS action list. In identification of the

generating units to control flow to ER, a cue may be taken from CERC Long Term,

Medium Term Open Access Regulations, 2009 which provide curtailment of power

scheduled to short term customer first followed by medium term customers and long

term customers for the reason of transmission constraint or in the interest of grid

security. Therefore to control flow towards ER the generating stations availing inter-

regional links to export power beyond WR should be identified and put under SPS.

During discussions it was felt that, the above arguments are valid during the steady

state conditions. Also the scheduling is done based on the assessment of availability

of transmission corridors by considering designed contingencies stipulated in IEGC.

However in real time, as seen during the GDs, there is hardly any time for manual

intervention for taking corrective actions. The actions suggested above by NTPC may

require considerable time. Further the electrical flows follow law of physics and

curtailment of schedules may not be a solution for maintaining the system stable

under tripping of these lines, since this may lead to rush of power in the other

corridors and may lead to unnecessary tripping other elements in WR system.

MS WRPC stated that the above units have been identified based on the sensitivity

analysis carried out by WRLDC and these studies showed that the power flow in

Bina – Gwalior- Agra corridor is more sensitive to the above units. Generation control

at these units would control power inrush on other corridors after tripping of the line.

The total quantum of backing down from all the above units envisaged in the SPS is

only 500MW, as such NTPC shall not insist on excluding their units from SPS.

Therefore the SPS for backing down of generating units, in the event of tripping of

Agra-Gwalior lines would have to be implemented, for the security of the grid.

However NTPC retained their stand and did not agree for participating in back down

of generator as envisaged in SPS of Gwalior-Agra/Bina-Gwalior lines.

MS WRPC stated that non participation of NTPC would be again put up to WRPC.

Meeting ended with vote of thanks to participants, Shri. S.G. Patki and Chairman of

meeting.

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Annex-I LIST OF PARTICIPANTS

IN THE MEETING OF WRPC ON ACTION PLAN ON RECOMMENDATIONS OF ENQUIRY COMMITTEE ON GRID DISTRUBANCE HELD ON 29.11.2012

Sl.No. Name - Shri / Smt. Designation Organization

1. S.D. Taksande Member Secretary (I/c) WRPC

2. S. Satyanarayan Superintending Eng. WRPC

3. L.K.S. Rathore Executive Engineer WRPC

4. D.P. Singh Executive Engineer WRPC

5. P.D. Lone Executive Engineer WRPC

6. Shiva Suman Asst. Director WRPC

7. S.S. Rajurkar Superintending Eng. MSETCL

8. S.S. Kulkarni Superintending Eng. MSETCL

9. S.G. Purkar Exe. Engineer MSETCL

10. Vasant D. Pande Exe. Engineer MSETCL

11. R.H. Satpute Exe. Engineer MSETCL

12. Amit R. Kulkarni Asst. Engineer MSETCL

13. B.B. Mehta Addl. Chief Engineer GETCO

14. S.A. Patel Exe. Engineer GETCO

15. B.M. Shah Dy. Engineer GETCO

16. K.G. Patel Dy. Engineer GSECL

17. Pankaj Kolay Superintending Eng. CSPGCL

18. G.P. Rai Executive Engineer CSPGCL

19. P.A.R. Bende Chief Engineer MPPTCL

20. D.C. Jain Chief Engineer MPPTCL

21. R.P. Pandey Superintending Eng. MPPGCL

22. G.K. Dixit Asst. Engineer MPPGCL

23. P. Pentayya General Manager WRLDC

24. V.K. Shrivastav Addl. General Manager WRLDC

25. V.A. Murty Dy. General Manager WRLDC

26. C.S. Bobade Chief Manager WRLDC

27. K. Muralikrishna Chief Manager WRLDC

28. Pushpa Seshadri Chief Manager WRLDC

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29. M.A.K.P. Singh Member(P) NCA

30. S.G. Tenpe General Manager JPL

31. Om Prakash Hota Addl. General Manager APL

32. S.G. Patki Vice President Tata Power

33. V.R. Shrikhande Head Tata Power

34. Aditya Joshi AM Tata Power

35. Girish Jawale Manager Tata Power

36. Nilesh B. Patel AM WRTM

37. Jalkote P.S. General Manager DTPS-Rel.

38. B.K. Mohanty Dy. General Manager CGPL

39. P.P. Francis General Manager NTPC

40. A.K. Juneja General Manager NTPC

41. S.S. Sen General Manager NTPC

42. D. Roy Choudhury Addl. General Manager NTPC

43. E.P. Rao Addl. General Manager NTPC

44. Oswald Menezes Dy General Manager NTPC

45. Shilpa Agarwal Manager NTPC

46. P.K. Gupta Addl. General Manager RGPPL

47. Pravin Chitral Addl. General Manager Torrent Power

48. Mohan R. Waingonkar Sr. Manager R-Infra.

49. Uday Karandikar Addl. Vice President WRTMPL

50. S. Maskey O S TAPS

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Annexure - 2 STATUS OF ACTION TAKEN ON RECOMMENDATIONS OF THE ENQUIRY COMMITTEE ON GRID DISTURBANCE IN NORTHERN

REGION ON 30th JULY 2012 AND IN NORTHERN, EASTERN & NORTH-EASTERN REGION ON 31st JULY 2012. (As on 27-9-12)

S.No. RECOMMENDATIONS Action Taken

9.1.1

There is a need to review protection schemes. This Committee concurs with recommendation of previous enquiry committees that a thorough third party protection audit need to be carried out in time bound manner. This exercise should be repeated periodically and monitored by RPCs.

Action: RPCs, CTU, STUs Time Frame: 1 year

9.1.2

Till protection audit is taken up, there is need to take immediate review of zone-3 philosophy in particular. Techniques are available to modify characteristics of the relay so that it can distinguish between load encroachment and faults. These techniques and other alternatives should be explored immediately.

Action: RPCs, CTU, STUs Time Frame: Immediate

9.1.3

The application of synchro-phasor measurements from PMUs should be explored for protection systems. There is also an urgent need to deploy Special Protection System (SPS) in critical transmission elements. Also, there is need to make already approved SPS operational.

Action: RPCs, CTU Time Frame: 1 year

9.1.4

A complete independent audit of time synchronization of DRs, ELs and PMUs should be carried out.

Action: Generators, CTU, STUs. Time Frame: 1 month

9.2.1 Frequency band needs to be further tightened and

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brought close to 50 Hz. POSOCO may file an urgency application in Supreme Court for early resolution of the issue in view of the recent grid disturbances.

Action: POSOCO Time Frame: 1 month

9.2.2

A review of UI mechanism should be carried out in view of its impact on recent grid disturbances. Frequency control through UI may be phased out in a time bound manner and Generation reserves/Ancillary services may be used for frequency control. Appropriate regulatory mechanism needs to be put in place for this purpose. POSOCO should take up the matter with CERC.

Action: POSOCO Time Frame: 3 months

9.3

All STUs should immediately enable under frequency and df/dt based load shedding schemes. Central Commission should explore ways and means for implementation of various regulations issued under the Electricity Act, 2003. Any violation of these regulations can prove to be costly as has been the case this time. RPCs need to take up the matter for compliance. In case non-compliance persists, POSOCO should approach Central Commission.

Action: STUs, RPCs, POSOCO Time Frame: Immediate

9.4 All out efforts should be made to implement provisions of IEGC with regard to governor action. Central Commission needs to look into ways and means to hasten implementation of provisions of IEGC including that on governor action. POSOCO need to take up the matter with Central Commission.

Action: POSOCO Time Frame: 3 months

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9.5.1 POSOCO should take up with Central Commission the issue of inconsistency between Congestion regulation and the detailed procedure framed there under so that congestion due to forced outages and Unscheduled Interchange (UI) can be handled effectively.

Action: POSOCO Time Frame: 1 month

9.5.2

NLDC and each RLDC should have one real-time security desk in all the shifts to be manned by engineer capable of carrying out TTC calculations. To facilitate this, manpower at NLDC and RLDCs need to be enhanced with regulatory support to take care of financial aspects. Till this arrangement can be firmed up, various scenarios of outages could be built, which then can be used by despatcher in real time. Faster algorithm for calculation of TTC may be adopted by the load despatchers to update it in real time under outage conditions.

Action: POSOCO Time Frame: 6 months

9.6 Outage planning of inter-State and inter-regional transmission elements should be carried out in a coordinated manner at RPC fora (say Operation Co-ordination sub-committee of RPCs) in accordance with regulation 5 of Central Electricity Authority (Grid Standards) Regulation, 2010 and Section 5.7.1 of Indian Electricity Grid Code. In case need for emergency maintenance arises in between two meeting of Operation Co-ordination sub-committee, NLDC and RLDCs should allow such maintenance after carefully looking at prevailing system conditions under intimation to RPC Secretariat.

Action: RPCs Time Frame: Immediate

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9.7 In order to avoid frequent outages/opening of lines under over voltages and also providing voltage support under steady state and dynamic conditions, installation of adequate static and dynamic reactive power compensators should be planned.

Action: CEA, CTU, STUs Time Frame: 6 months

9.8 The powers of Load Despatch Centres and Regulatory Commissions related to non-compliance of statutory/regulatory provisions including that for non-compliance of directions and non-payment of UI charges, need review. Appropriate amendments need to be carried out in the Electricity Act, 2003 after such review.

Action: Ministry of Power, GoI. Time Frame: 6 months

9.9.1 The regulatory provisions regarding absorption of reactive power by generating units needs to be implemented

Action: POSOCO Time Frame: Immediate

9.9.2 An audit of devices such as HVDC, TCSC, SVC and PSS should be done immediately to ensure that their stability features are enabled. Further, exercise of PSS tuning should be planned and implemented. Settings of these dynamic stabilizing devices should be reviewed at appropriate intervals.

Action: CTU, STUs, Generators Time Frame: 6 months

9.9.3 Functioning of existing PMUs and availability of their output to RLDCs and accuracy of time synchronization should be monitored on daily basis and, if required, corrective actions should be taken on priority basis.

Action: CTU, POSOCO Time Frame: Immediate

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9.10.1

The synchrophasor based WAMS employing PMUs offer a wide applications for real time monitoring and control of the system, specially under the dynamic conditions. Adequate number of PMUs should be installed to improve the visibility and real time monitoring of the system. Further the applications related to the synchrophasor based wide area monitoring, protection and control should be embedded in the system.

Action: CTU Time Frame: 1 year

9.10.2

Possibility of voltage collapse prediction, sensing global power system conditions derived from local measurements may be explored.

Action: RPCs Time Frame: 1 year

9.11 Need of Dynamic Security Assessment and review of State Estimation In order to assess the system security in real time and assess the vulnerability condition of the system, dynamic security assessment need to be periodically carried out at the control centers. A proper review and upgradation of the state estimation procedure is required to improve the visibility and situational awareness of the system.

Action: POSOCO Time Frame: 6 months

9.12 Efforts should be made to design islanding scheme based on frequency sensing relays so that in case of imminent grid failure, electrical islands can be formed. These electrical islands can not only help in maintaining supply to essential services but would also help in faster restoration of grid.

Action: CEA, RPCs, POWERGRID, STUs, SLDCs and Generators

Time Frame: 6 months

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9.13.1

As National Grid is on the horizon, homogenization of system operation philosophy is need of the hour. The present organizational set up of Load Despatch Centres need to be reviewed. System operation needs to be entrusted to Independent System Operator (ISO). In addition, SLDCs should be reinforced and ring fenced for ensuring functional autonomy.

Action: Govt. of India, State Govts. Time Frame: 1 year

9.13.2

Training and certification of system operators need to be given focussed attention. Sufficient financial incentives need to be given to certified system operators so that system operation gets recognized as specialized activity.

Action: Govt. of India, State Govts. Time Frame: 3 months

9.14

Intra-State transmission system needs to be planned and strengthened in a better way to avoid problems of frequent congestion.

Action: STUs Time Frame: 2 years

9.15.1

Appropriate amendments should be carried out in Grid Connectivity Standards to restrain connectivity of a generating station or a transmission element without required communication and telemetry facilities.

Action: CEA. Time Frame: 6 months

9.15.2

The Communication network should be strengthened by putting fibre optic communication system. Further, the Communication network should be maintained properly to ensure reliability of data at Load Despatch Centers.

Action: CTU and STUs Time Frame: One years

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9.15.3

RTUs and communication equipment should have uninterrupted power supply with proper battery backup so that in case of total power failure, supervisory control and data acquisition channels do not fail.

Action: CTU and STUs Time Frame: 3 months

9.15.4

In case of existing generating stations or transmission elements without telemetry facility, the same should be put in place at the earliest. If prolonged operation without telemetry continues, POSOCO should approach Central Commission.

Action: RPCs, POSOCO Time Frame: 6 months

9.16

Large variations are observed in time taken for initiation of unit start up (Boiler light up) by the stations after availability of start-up power and also for start ups/light up of subsequent units. While subsequent start-ups were very fast (10-20 minutes) in some of the units, in other cases they took considerably longer time – several hours. Reasons for the delays in attempting first start-up and subsequent start-ups may be examined by the utilities in consultation with CEA. A standard procedure for preparatory activities and sequence of start up may be put in place by the stations to restore units as early as possible particularly in contingencies.

Action: CEA, Generating Utilities and RLDCs Time Frame: one year

9.17 At inter-State level, the entire landscape has changed over past few years. With de-licensing of generation and provision of open access in Electricity Act, 2003 and development of organized electricity markets, lot of generation is coming in the form of merchant generation. Four out of the five regions have been integrated and formation of National Grid is on the horizon. Under such scenario, there is need to review the Transmission Planning criteria.

Action: CEA Time Frame: 3 months

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9.18 There is need to reinforce system study groups in power sector organisations to analyse the system behaviour under different network status/ tripping of lines/outage of generators. Where these do not exist, these should be created.

Action: CEA, CTU and STU Time Span: one year

9.19

It was felt that a separate task force may be formed, involving experts from academics, power utilities and system operators, to carry out a detailed analysis of the present grid conditions and anticipated scenarios which might lead to any such disturbances in future. The committee may identify medium and long term corrective measures as well as technological solutions to improve the health of the grid.

Action: MOP, CEA Time Frame: 1 month

9.20 For smooth operation of grid systems, it is absolutely important that all the power generating and distributing stations are connected on a very reliable telecom network. (i) A proper network may be built up preferably using

MPLS (Multi Protocol Label Switching) which is simple, cost effective and reliable. In remote place where connectivity is a problem, the stations can use dedicated fibre cable from the nearest node.

(ii) Since POWERGRID has its own fibre optic cables, practically covering all major nodes and power stations, a proper communication/IT network may be built using dedicated fibres to avoid any cyber attack on the power system.Action: CTU, STUs

Time frame: 1 Yr

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