The Transmission Company of Nigeria (TCN) announced on Tuesday that power supply has been fully restored to areas affected by an arcing incident on the Benin-Egbin 330 Kilovolt (kV) isolator.
The incident occurred on Monday, with power being restored around 6:10 p.m.
Arcing, an electrical discharge occurring between two conductors in a gas or vacuum environment, caused a heavy system surge that led to the arcing of the Benin-Egbin 330kV line isolator at the Egbin Transmission Substation switchyard. This surge led to the tripping of lines, resulting in a temporary loss of power supply to several areas.
Mrs. Ndidi Mbah, TCN’s General Manager of Public Affairs, explained that the problem began around 2:47 p.m. with a heavy system surge, which caused the arcing and tripping of the Benin-Egbin 330kV line isolator.
This disruption affected the Egbin Generating Station and led to the loss of power supply to all outgoing lines from the Egbin Transmission Substation.
The issue also caused a significant load increase on the Osogbo-Ihovbor 330kV line 1, leading to further arcing of isolator terminals.
To prevent a system collapse, the Osogbo-Ihovbor 330kV line was temporarily opened to cut off the electricity flow.
By 2:56 p.m. on Monday, the Benin-Egbin 330kV line 1 Circuit Breaker tripped at the Benin Transmission Substation end, resulting in a loss of supply to the Lagos axis, parts of the South West Region, parts of North Central, and Abuja. Other regions, including the South East, North East, and remaining parts of North Central and South West, maintained full power supply.
The situation was quickly addressed, and the grid controller restored full bulk power supply through the transmission lines by approximately 6:10 p.m. on Monday.
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