基于模糊概率重要度的可靠性分析方法

摘要

故障树分析中基本事件的重要度对顶事件的发生概率有着重要的影响.文中提出了一种基于模糊概率重要度的发动机可靠性分析方法,对事件发生概率进行分析,以克服传统故障树分析无法处理模糊和不确定信息的缺点.用模糊三角数来描述基本事件和顶事件的发生概率,以不同的权重指数描述去除相应的基本事件之后顶事件概率的变化.通过计算不同a截集下各个基本事件及顶事件的概率,对各基本事件的概率重要度进行排序,据此可以提出改进意见和措施.以应用实例对提出的方法进行了验证.%The importance degree of the basic events has important influence on the occurrence probability of the top event in the fault tree analysis. In order to overcome the disadvantage that the traditional fault tree can't deal with the fuzzy and uncertain information, an engine reliability analysis method based on fuzzy possibility importance degree is presented to analyze the occurrence probability of the events in this paper. The triangular fuzzy number is used to describe the occurrence probability of the basic events and top event. The different weighted indexes is used to describe the change of the probability of the top event in which the corresponding basic event is eliminated. The ranking of the probability importance degree of each basic event can be conducted by calculating the probability of each basic event and the top event with different a-cut sets. According to the analysis results, the improvement views and measures can be suggested. Finally, an application example is illustrated to verity that the proposed method is effective and feasible.