基于多故障假设的诊断策略研究与应用

 针对工程中最优单故障序贯测试难以隔离的多故障问题,利用Grunberg等人提出的多故障模糊组的概念,以最优单故障测试策略为基础,构造了一种多故障假设下的序贯测试算法．该算法以多故障状态集的最小碰集作为生成最优单故障策略的故障状态,生成最优单故障策略；以诊断决策树中各叶节点的多故障状态集为评判标准,确定系统的状态,完成多故障假设下的系统故障诊断；与连续使用单故障策略的方法相比,该方法提高了测试效率．以某型机载电子设备为例给出算例分析,验证了该算法隔离多故障的有效性．

Research and application on multiple fault diagnosis strategy

Aiming at the problem that it is difficult to diagnose multiple faults by optimal single fault sequential test, a new sequential testing algorithm for multi-fault diagnosis based on optimal single fault test strategy is presented by employing the concepts of multi-fault ambiguity groups put forward by Grunberg etc. This algorithm takes the minimal hitting sets of multi-fault state sets as fault states to generate the optimal single fault strategy. By taking the multi fault state sets of each leaf node in decision-making tree as evaluating standards, system state can be determined, and then system diagnosis under the assumption of multiple faults is completed. Compared with the strategy of successively employing single-fault diagnosis, the efficiency of diagnosis is increased. Finally the real system on some active spacecraft was taken as an instance to demonstrate the validity of the strategy. 