Research on Fault Diagnosis Approach Based on the Signed Directed Graph Model for Nuclear Power Plant

Signed Directed Graph (SDG) is a kind of fault diagnosis method based on a qualitative model. SDG can not only efficiently express the interrelations among variables of complex systems and has strong completeness, flexible reasoning ways and effective reasoning algorithm, but also shows faults propagation paths and faults detailed explanations. In this paper, SDG is applied to fault diagnosis in nuclear power plant which is a large-scale and complex system, and diagnosis results are transformed into a series of expert rules. The case studies show this method can find faults propagation paths and fault source can be determined effectively and improve the efficiency of fault diagnosis. The application of SDG in nuclear power plant can provide operation support to operators, so as to guarantee the safe and stable operation of the system.Copyright © 2013 by ASME