基于最大故障特征信息量准则的故障搜索策略

针对利用故障树搜索故障时路径不惟一的问题,研究利用诊断树进行故障搜索的策略。利用信息论中自信息和熵的概念,给出了故障特征信息量的定义,介绍了故障特征信息量的计算方法。制定系统的故障搜索策略时,首先选择故障特征信息量最大的特征进行测试。根据对故障特征的测试顺序建立诊断树,然后按照诊断树搜索系统故障。利用这种方法,可以根据前一个故障特征的状态来决定下一步测试或检查的内容,使故障搜索策略具有自适应特性,实现系统故障的动态和快速搜索。

Fault Search Strategy Based on Rule of Maximum Fault Signature Information Content

When the fault cause is searched through the fault tree(FT),the search path is not exclusive.For this reason,the fault search strategy through diagnosis tree(DT) is examined.The fault signature information content is defined using the concepts of self-information and entropy in the information theory,and the algorithm of the fault signature information content is presented.When the fault search strategy for the system is made,the fault signature with maximum fault signature information content should be chosen to test firstly.The DT is built according to the test sequence of the fault signatures.Then the fault can be searched through DT.In this way,the next fault signature to test is determined according to the test result for the current fault signature.Therefore,the fault search strategy made through DT is of adaptive characteristic,and the fault can be searched dynamically and rapidly.