Tripping cause of third blackout

The Ceylon Electricity Board on Sunday said that the cause for the third islandwide blackout this year on Saturday was the tripping at the Kelanitissa power station.

A statement of the CEB said:

The Ceylon Electricity Board, which has made a full study of the cause for the total failure which occurred at 02.56 p.m. on Saturday 11th January 2003, has identified the cause as the tripping of the Combined Cycle generating plant at the Kelanitissa Power Station being commissioned by the Contractors. The tripping was due to a fire alarm within the generating plant.

At the time of the failure this plant was running with a load of about 120 MW. The generator’s gas turbine part supplied 87MW and the balance was supplied by the steam part.

The total system demand just prior to the tripping was 777 MW. The other generators connected to the Kelanitissa Power Station at that time were the Barge-mounted generator, the Gas Turbine GT7 and the AES plant. This AES plant was also undergoing tests by their personnel. Once the trip by fire alarm occurred and threw off some 120MW from the grid, the other generators at Kelanitssa, hydro generators and smaller thermals running on the system also tripped in a cascade manner.

Immediately after this, restoration of supply to the grid was commenced in stages, the Biyagama sub station being restored at 3.11 p.m. namely within 15 minutes. The Colombo city and other areas were restored by 4.00 p.m. in stages starting at 3.30 p.m. Vavuniya and Trincomalee were the last to be restored; by 04.22 p.m.

The Ceylon Electricity Board wishes to tender its apologies to the consumers and the general public for the inconvenience caused. Every endeavour will be made to prevent recurrence of such incidents. However, the public should bear in mind that the system was in a relatively poor condition at the beginning of 2002. The last 12 months have been spent in refurbishing the various components of the system.