Selection of optimum maintenance strategy for power plant equipment based on evidential reasoning and FMEA

Aiming at the problem that it is difficult to select optimum maintenance strategy for power plant equipment, a method based on criticality evaluation and failure mode characteristic analysis is put forward. In the method, the uncertainty and incompletion of criticality evaluation factors are completely considered, qualitative and quantitative evidences are integrated and their acquisition and transformation method is put forward based on constructing criticality evaluation multiple-attribute decision tree. Then a decision tree criticality evaluation model is established, a corresponding evidential reasoning algorithm is deduced, and the equipment in power plant is ranked by criticality. Integrating the results of criticality evaluation and failure mode and effect analysis (FMEA), the decision model of selecting optimum maintenance strategy of power plant equipment is established and applied in a fossil-fired power station. It is shown by the instance that this method is feasible and effective, can select optimum maintenance strategy for power plant equipment.