论文部分内容阅读
基于设备故障诊断知识的特点，采用层次树结构统一表示故障深浅知识。对普通Ｐｅｔｒｉ 网进行拓展定义，并用拓展Ｐｅｔｒｉ 网综合实现故障知识的表示和故障的诊断推理。诊断时首先基于拓展Ｐｅｔｒｉ 网模型的正向可达性分析进行正向不确定推理，限定可能的故障模块，然后基于Ｐｅｔｒｉ 网模型的反向推理功能在故障模块内具体诊断出故障原因。基于ＦＭＳ故障诊断知识的分析，文中给出了一个利用拓展Ｐｅｔｒｉ 网进行知识表示和推理的实例，证明了方法的可行性。
Based on the characteristics of equipment fault diagnosis knowledge, hierarchical tree structure is used to represent the knowledge of fault depth. The definition of ordinary Petri nets is extended, and the representation and fault diagnosis of fault knowledge are realized by using extended Petri nets. First of all, based on the analysis of the forward accessibility of the extended Petri nets model, a positive uncertainty reasoning is first defined to limit the possible fault modules. Then, the reverse reasoning function based on the Petri net model is used to diagnose the cause of the fault in the fault module. Based on the analysis of FMS fault diagnosis knowledge, an example of using extended Petri nets for knowledge representation and reasoning is given, and the feasibility of the method is proved.