T-S模糊重要度分析方法研究

Research on T-S Fuzzy Importance Analysis Methods

针对故障树分析中部件失效概率、故障状态和系统故障机理的不确定性问题,用模糊子集来表示部件的失效可能性,用模糊数来描述部件和系统的故障状态,用T-S模糊模型来描述部件之间的联系,在T-S模糊故障树分析算法基础上,提出两种T-S模糊重要度:拓展传统二态系统模糊重要度的重心法,综合部件所有故障状态的失效可能性对系统重要程度的影响,定义多态系统T-S模糊重要度,并由算例对比得出,传统模糊重要度可看作是T-S模糊重要度的一个特例,T-S模糊重要度更为一般化;在仅已知部件故障状态的情况下,提出T-S状态重要度的概念及其计算方法。对某导航系统进行重要度分析,验证了算法的有效性。

In order to overcome the uncertainties of components failure probabilities and fault states and fault mechanisms in fault tree analysis,the components failure possibilities are denoted by fuzzy subsets,the fault states of components and system are expressed as fuzzy numbers,the components＇ relations are described by T-S fuzzy model.On the basis of T-S fuzzy fault tree analysis method,two kinds of T-S fuzzy importance algorithms are proposed： Combining with the influence of all fault states＇ failure possibilities of components on the importance degree of system,the T-S fuzzy importance of multi-state system is defined by extending the centroid method of the conventional two-state system fuzzy importance,it is showed that the conventional fuzzy importance can be regarded as a special example of the T-S fuzzy importance and the proposed algorithm is more general;Under the condition of only knowing components fault states,the concept and calculation method of T-S state importance are presented.It is proved that the algorithms are feasible by importance analysis of a certain navigation system.