Outage of 400 KV Bina-Gwalior-Agra line likely cause of grid failure

Outage of 400 KV Bina-Gwalior-Agra line likely cause of grid failure
V K Gupta
02 August, 2012
The grid failures may not be the result of power overdrawing by various states. This exclusive analysis has been made on basis of official data. 1
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THE OUTAGE of 400 KV Bina-Gwalior-Agra for up-gradation since July 28 is the likely cause of two grid failures on two consecutive days and not power overdrawing by states as is being made out.

National Load Dispatch Centre (NLDC) has now revised the limits of inter - regional power transmission from different 765 and 400 KV transmission lines in view of recent grid failures. NLDC has pointed out that in case of both grid failures there was heavy power flow on the 400 kV Bina-Gwalior-Agra single circuit section crossing 1000 MW on the single circuit available.

It may be mentioned that the 765 KV transmission line was being operated at 400 KV. The second circuit of 400 KV Bina- Gwalior –Agra line was under outage since 28th July for up-gradation to 765 KV level. Grid failure was averted earlier at 1510 hours on 29th July 2012 under similar conditions.

A senior power sector expert said that since the up-gradation of 400 KV Bina –Agra transmission line is a planned work and it should have been taken during the lean period. It is well known that power load in northern region is at its peak during paddy season. Moreover the monsoon this year has been below normal and power demand surpassed utilities estimates.

NLDC in consultation with Central Electricity Authority and CTU has worked out the Short Term Open Access (STOA) approvals by to be given by Regional Load Dispatch Centers .Further if at any time due to an emergency in the system, RLDCs would take all. Actions necessary to ensure system security including curtailment of transactions.

The available margin for short term open access from western grid to northern grid through 400 KV Bina – Gwalior –Agra line has been fixed at 790 MW. Similarly the power transfer from eastern grid to northern grid has been fixed at 2492 MW through 400 KV Kahalgoan-Bihrshrief transmission lines. Similar power transfer has been revised for other inter regional power transfers.