In a power plant environment, what type of test are required before reconnect the generator to the grid in the event of a fault located between the main transformer (GSU) and the HV switchyard?
System Description: There is three generators, with total capacity of approximately 800 MVA,18kV connected to 3-GSUs (Generator Step-up Transformers) 18kV/345kV interconnected to a single 345 kV bus and then connected to a ring bus switchyard 345 kV via a single T. Line (approx 1 mi).
Predicated fault: A fault in the 345 kV will stress generators, GCB, GSU, etc
Usual Practice after fault: I know general utility practice do not reclose on transformer and UG cable faults until a maintenance crew verify that there is not permanently damage if they re-energize.
Rational: I presume that similar procedures are used in generator and other important equipments after fault. I am curious about type of test and typical duration or rought downtime per generator if available.
OK, but how does it work? three fulltime? one or two stand-by?. Fault triggers all breakers, generators stop. If selective coordination works i think you only have to check protections, if it is a full time systems that the best chance to inspect everything.
If there was no electricity there would be no internet. Good point, don´t you?