PPN: A probabilistic model for fault detection and diagnosis

To analyze the composite fault in Discrete Event System (DES), a Probabilistic Petri net (PPN) and a fault diagnosis method for power system are proposed. Firstly, the PPN models are established on every fault spread direction. Secondly, the failed component is determined by the application of Petri net reasoning and probabilistic calculation. At last, the result is given by fusing all parties´ results using mean method. Diagnosis analysis shows that the method can adapt to topology changes and obtain satisfying diagnosis results with incomplete information. In the PPN reasoning, calculating the fault probability of component is based on the prior probability from statistics, so the subjectivity of setting related parameters can be avoided.