基于等效失效率的动态故障树分析

基于等效失效率的动态故障树分析
李振，(第二炮兵工程学院．孙新利 陕西西安710025)
摘 要：运用动态故障树对动态系统进行可靠性定量分析，当动态子树规模较大时，直接运用马尔可夫理论的难度较大≮在综合运用模块化、等效失效率方法的基础上，提出了一种动态故障树顶事件发生概率的近似算法：首先通过深度优先最左遍历来搜索独立模块；接着，对时间域进行不等距划分。将动态门下的子模块看作“准底事件-’．利用其在各区间内的等效失效率来逐步求取整个动态故障树顶事件的发生概率吾通过对实例的求解。验证了此方法的有效性
关键词 动态故障树；深度优先最左遍历}等效失效率；马尔可夫理论
中图分类号：TB1 14．3 文献标识码：A 文章编号：1672-5468(2007)04．0o26-04
Dynamic Fault Tree Analysis Based on Equivalent Failure Rate
LI—Zhen，SUN Xin—li
(The Second Artillery Engineering Institute，Xi’an 7 10025，China)
Abstract：In case of applying the dynamic fault tree to the quantitative analysis of dynamic system， it is dificult to use Markov theory directly when the dynamic sub-tree is very complex．

Based on modularization and equivalent failure rate， an approximate algorithm for top-event occu~ence rate of dynamic fault tree was introduced．At first，independent modules are recognized through the depth first left most ergodic algorithm．Then，the time domain is divided into nonequidistant intervals． A submodule included in the dynamic gate is considered as an approximate base ovent and its equivalent failure rate in each interval is used to obtain the top—event occurrence rate of the whole dynamic fault tree step by step．The effectiveness of the algorithm is demostrated with an practical example．
Key words：dynamic fault tree；depth first left most ergodic algorithm；equivalent failure rate；Markov theory