29 August 2020 10:18 am
The Electrical Superintendent at the Kerawalapitya Grid sub-station as well as the Protection Scheme of the Ceylon Electricity Board (CEB) must take the responsibility for the island wide power outage on August 17, the interim report of the nine member committee that probed the biggest ever blackout in the country, has concluded.
The report strongly recommends a standard compliant, systemic, fool proof, safe procedures and maintenance protocols to be instated in CEB during operations and maintenance to prevent a repetition of a major breakdown of power supply of this magnitude in future.
Prof. Rahula Attalage, chairman of the committee told the media yesterday that the committee in its inquiry found that the key reason for the nationwide power interruption on the August 17, 2020 was due to the 3 Phase to Ground busbar fault that resulted in incorrect operation of the Busbar 2 Isolator of the Bus Coupler Bay by the Electrical Superintendent in Charge at the Kerawalapitiya Grid Substation.
“Kerawalapitiya Grid substation tripping was due to failure to follow the correct maintenance procedure by the relevant officials including the Electrical Superintendent. The committee also observed that there is no written maintenance protocol for this maintenance job inline with the current best practiced maintenance protocols,’ he said.
The committee is of the view that due to the Kerawalapitiya Grid substation tripping, the system frequency increased beyond the current setting of the rate of frequency tripping relay of the Lak Vijaya Power Station. As a result, the generator-transformer circuits breakers of all three units of the LVPS which made LVPS unavailable to the grid, subsequently failed in the system, in cascade, Prof. Attalage added. By Sandun A Jayasekera