Instability Fault Knowledge Acquisition and Management of Pumped Storage Unit Based on FTA / FMEA and Ontology Theory

The operation condition of pumped storage unit is complex and switch frequently, which is easy to cause unit instability fault. Firstly, the pumped storage unit structure is decomposed according to the level of ‘system- subsystem- component’. The unit is divided into four subsystems in structure: motor-generator subsystem, pump turbine subsystem, pressure diversion subsystem and speed control subsystem. The unit equipment tree is established. Combined with unit operation characteristics and typical instability fault cases, the typical instability fault modes of pumped storage unit are determined. Then, FTA (Fault Tree Analysis) and FMEA (Failure Mode And Effects Analysis) are combined to obtain the instability fault knowledge of the unit by performing FTA first and then FMEA. Finally, aiming at the equipment structure information, FTA information and FMEA information of pumped storage unit, combined with ontology theory, the class and attribute relationship of the three types information ontology are analyzed. And the equipment information ontology, FTA ontology and FMEA ontology models are constructed respectively to realize the representation and management of fault knowledge.