USA, Washington: After a sudden shutdown due to transformer fault, Columbia Generating Station near Richland reconnected to the regional power grid last week.
Energy Northwest, the public agency operating the plant, continues the investigation into the transformer issue that caused the nuclear plant to shut down, reports Tri-City Herald.
According to the operator, one of the plant's main power transformers automatically disconnected from the transmission system following a grid disturbance on 18 May. The transformer's protection system detected an issue and tripped, which caused the main generator also to trip and the plant to stop operating.
The part of the transformer that tripped has been sent for analysis.
The downtime was used to perform maintenance on plant equipment, including working on valves, which cannot be done when the plant is operating.
Source: Tri-City Herald