July 21, (THEWILL) – The Transmission Company of Nigeria (TCN) says the collapse of the national grid occurred due to the sudden drop in system frequency from 49.94 Hertz (HZ) to 47.36Hz, which created system instability.
”The incident was a result of sudden drop in system frequency from 49.94 Hertz (HZ) to 47.36Hz, which created system instability”, TCN said in a statement issued on Thursday, by its General Manager, Public Affairs, Mrs Ndidi Mbah.
Hertz is a unit of frequency which replaces the earlier term of one cycle per second (cps).
Mbah said that reports from the National Control Centre (NCC), revealed that the collapse was precipitated by the tripping of a unit with a load of 106 Megawatts (MW) in one of the generating stations due to “Exhaust over Temperature.”
She explained that the tripping pulled out other grid-connected units in the plant, which resulted in aggregated generation loss of 457MW.
“A train of events ensued, culminating in the collapse of the national grid. As obtainable in all systems, when a component of the electric power system is defective, the entire configuration is vitiated”, she said, adding that investigation was going on to establish the cause of the failure.
Meanwhile, Mbah also disclosed that the restoration of the national grid was almost completed following its collapse on Wednesday.
She said that the national grid experienced system disturbance at about 11:27a.m. on Wednesday, but that its restoration was almost completed as at 11:00p.m.
The TCN spokesperson said the Nigerian Electricity Supply Industry (NESI) appreciated the understanding of the government and consumers of electricity within and outside the country, noting that NESI was committed to leveraging on interventions instituted thus far to enhance power supply reliability.
