CHAPTER-1
INTRODUCTION
1.1 There was a major grid disturbance at 02.33 hrs on 30-07-2012 in Northern region and again at 13.00 hrs on 31-07-2012 resulting in collapse of Northern, Eastern, North-Eastern regional grids barring a few pockets.
1.2 The first disturbance which led to the collapse of Northern Regional Electricity grid occurred at 02.33 hrs on 30th July, 2012, in which all states of Northern Region viz. Uttar Pradesh, Uttarakhand, Rajasthan, Punjab, Haryana, Himachal Pradesh, Jammu & Kashmir, Delhi and Union Territory of Chandigarh were affected. Northern Regional Grid’s load was about 36,000 MW at the time of disturbance. Small islands which comprised of three units of BTPS with the load of approximately 250 MW in Delhi, NAPS on houseload, Area around Bhinmal (Rajasthan) with approximate load of 100 MW connected with Western Region survived the blackout. Restoration was completed by 16.00 hrs.
1.3 The second incident which was more severe than the previous one occurred at 13.00 hours on 31.7.2012, leading to loss of power supply in three regions of the country viz. Northern Region, Eastern Region and North Eastern Region affecting all states of Northern Region and also West Bengal, Bihar, Jharkhand, Odisha, Sikkim in Eastern region and Assam, Arunachal Pradesh, Meghalaya, Manipur, Mizoram, Nagaland and Tripura in North-Eastern region. The total load of about 48,000 MW was affected in this black out. Islands comprising of NAPS, Anta GPS, Dadri GPS and Faridabad in Northern Region, Ib TPS / Sterite, Bokaro steel and CESC survived in Eastern Region. It has been reported that major part of the system could be restored in about 5 hrs, 8hrs and 2 hrs in Northern, Eastern and North-Eastern regions respectively.
1.4 To look into the detailed causes of these disturbances and to suggest remedial measures, Ministry of Power vide its OM No. 17/1/2012-OM Dt. 30-07-2012 constituted an Enquiry Committee headed by Chairperson, CEA and CEO, POSOCO and CMD POWERGRID as members. With the second major grid disturbance on 31-07-2012 involving three regions the Ministry of Power vide its OM No. 17/1/2012-OM Dt. 03-08-2012 modified the constitution of the above enquiry committee with following members:
(i) Shri A.S. Bakshi, Chairperson, CEA Chairman
(ii) Shri A. Velayutham, Member (retd.), MERC Member
(iii) Dr. S. C. Srivastava, IIT Kanpur Member
(iv) Sh. K. K. Agrawal, Member (GO&D), CEA Member Secretary
1.5 In addition, following members assisted the Committee:
(i) Shri R. N. Nayak, CMD, POWERGRID
(ii) Shri S. K. Soonee, CEO, POSOCO
(iii) Shri Balvinder Singh, IPS Retired.
1.6 The Terms of Reference of the Committee are as under:
a) To analyse the causes and circumstances leading to the grid disturbance affecting power supply in the affected region.
b) To suggest remedial measures to avoid recurrence of such disturbance in future.
c) To review the restoration of system following the disturbances and suggest measures for improvement in this regard, if any
d) Other relevant issues concerned with safe and secure operation of the Grid.
1.7 The Committee has been asked to submit its report by 16th August, 2012. A copy of MoP OM dated 3-8-2012 constituting the above Committee is given at Annexure-1.1.
1.8 First meeting of the initially constituted Enquiry Committee was held on 01-08-2012. Second meeting of the Enquiry Committee was held on 03-08-2012 which was attended by the members of the Committee and representatives of NLDC, all RPCs, RLDCs, POSOCO and POWERGRID.
1.9 The Committee constituted five sub-groups to facilitate detailed and quick analysis of various aspects of grid disturbances viz.
(i) ‘Analysis of grid collapse on 30th& 31st July 2012 and simulation of the event’ under Shri A. Velayutham, Ex. Member, MERC and Prof. S.C. Srivastava, IIT, Kanpur assisted by Dr. Anil Kulkarni, IIT, Bombay, Shri Ajay Talegaonkar, SE (Operation), NRPC & Shri S. Satyanarayan, SE (Operation), WRPC,
(ii) ‘Islanding scheme for Railways & Delhi Metro’ under Shri K.K. Agrawal, Member (GO&D), CEA,
(iii) ‘Analysis of restoration process of thermal plants’ under Shri Manjit Singh, Member (Thermal), CEA,
(iv) ‘Islanding schemes in Northern Region’ under Shri P.K. Pahwa, Member Secretary, NRPC,
(v) ‘Cyber Security aspects’ under Shri Ajit Singh, Ex-Addl. Secretary, Cabinet Secretariat and Shri R.K. Verma, Chief Engineer I/c (DP&D), CEA
1.10 In addition, a sub-group comprising Shri Dinesh Chandra, Chief Engineer I/c and Shri D.K. Srivastava, Director, Grid Management Division was formed to compile and prepare the report based on the progress made by the five sub-groups on day-to-day basis.
1.11 For secure grid operation after two grid collapses, following steps were taken immediately:
a) NLDC reduced the TTC of the Inter-Regional lines and other critical lines limiting to its SIL thereby necessary restrictions imposed on STOA.
b) CEA advised utilities that senior and experienced officials should be available in RLDCs, SLDCs, Generating Stations and Sub-Stations for at least one week.
c) CEA also advised to all generating stations to be responsive and develop a mechanism for bringing Units at the earliest in case of contingencies.
1.12 Enquiry Committee held its third meeting on 11-8-2012. On 12-8-2012, detailed discussions were held with POSOCO and POWERGRID at NLDC, New Delhi to have their view points on the causes of grid collapse. The Committee finalized its findings in its meetings on 14th and 15th August, 2012.
1.13 The Committee analysed the output of Disturbance Recorders (DR), Event loggers (EL), PMUs, WAFMS, SCADA data and reports submitted by various SLDCs , RLDCs /NLDC, POWERGRID and generation utilities to arrive at the sequence of events leading to the blackouts on 30th July, 2012 and 31st July 2012. The Committee also interacted with POWERGRID and POSOCO on various aspects of these grid disturbances. Some teams also made field visits to sub-stations, generating stations, NRLDC, NLDC, UPSLDC and Haryana SLDC.
