(in lingua inglese)
The operators of power station control room need to a system to aid and support them to make reasonable decisions during critical situations and reducing the delay of restoration after emergency, a simplified Petri nets fault diagnosis system is proposed to deal with a lot of alarms and tripping signals which are sent to the power station control room. The paper proposes a fault diagnosis system based on Petri net for a large power generation station, which includes: generation units, step up power transformers, block bus, station service transformers, autotransformers and station buses.