The Transmission Company of Nigeria (TCN) has restored normal bulk transmission of electricity to its Apo transmission substation after a fire destroyed one of its 45MVA 132/33kV power transformers on Sunday.
The burnt 45MVA 132/33kv power transformer feeds electricity to Abuja Electricity Distribution Company (AEDC) 33kV feeders.
TCN’s General Manager, Public Affairs, Mrs Ndidi Mbah, in a statement on Monday said the fire was put off by the combined efforts of the Federal, FCT and NNPC fire service.
She, however, said it was still early for TCN to determine if the burnt transformer could be salvaged.
Mbah said that the fire resulted from a direct fault from one of AEDC’s 33kV feeders, which had a history of incessant tripping, noting that the 33kV lacked protection.
She said TCN was equally investigating the possibility of transformer protection failure on its 45MVA power transformer.
“The 33kV feeder H13 circuit breaker and current transformer exploded while the 33kV outgoing transformer snapped causing the fire,’’ Mbah said.
She, however, said the Apo transmission substation has N-I redundancy and as such, power supply to all the areas that take supply from the substation through AEDC would not be affected by the incident.
According to her, “This is because the maximum load taken by AEDC from the burnt 45MVA transformer was 26MW. Meanwhile, maximum load AEDC takes from the old 100MVA in the substation is 56.5MW.
“But maximum load from the second 100MVA power transformer installed last year is 30.8MW, both, however, can take at full capacity, a total of 160MW against the 86.5MW.’’
She said TCN was presently transmitting normal supply through the 2x100MVA 330/132kV and the second 45MVA 132/33kv power transformers in the substation.
Mbah said the company had equally loaded the 26MW from the burnt transformer into the 100MVA MBH transformer at the substation and is adequately supplying AEDC without load reduction.
She said TCN was working with AEDC to ensure that it now takes the load through the MBH 100MVA transformer instead of the burnt transformer.
The TCN General Manager apologised for the inconveniences caused electricity consumers in the affected areas, and noted that the issue of protection of equipment should be taken seriously.