基于TMSDG的民用飞机故障诊断隔离策略

 针对民用飞机排故时交互式故障诊断与隔离需求,在符号有向图(SDG)中补充状态节点的故障概率信息和未测状态表达,引入对测试节点的描述,提出了一种附带测试维修信息的SDG(TMSDG),给出了基于此模型的交互诊断流程。首先根据初始征兆获取可疑集,然后综合可靠性和测试代价等因素生成一种基于最小测试代价的诊断二叉树对初始可疑集进一步隔离。该模型能描述复杂系统中存在的状态关联和故障测试依赖关系,对其中故障进行交互式诊断和隔离指导。利用该方法建立了某飞机发动机高压引气的诊断模型,实验结果表明提出的方法有效。该方法适用于飞机的外场故障诊断与隔离。

Fault Diagnosis and Isolation Strategy for Civil Aircraft Based on TMSDG

To meet the requirements of interactive diagnosis and isolation of civil aircraft troubleshooting,a test-maintaince signed directed graph(TMSDG) method with test and maintenance information is proposed by introducing the fault probability,unmeasured status and test nodes in signed directed graph(SDG).A procedure of interactive diagnosis based on TMSDG is proposed.First,according to initial symptoms,an initial suspect set is reasoned.Then,an optimal binary diagnosis tree with the minimal expected test cost is developed considering fault probability and testing cost,and the initial suspect set can be further isolated using the binary diagnosis tree.The complicated status association and fault-test dependency of a complex system fault can be modeled and interactively diagnosed by the proposed method.Finally,a fault diagnosis model of an aircraft engine bleed system is built up with the proposed method.The case results prove the effect and utility of this model,which suggests that the method may be suitable for application in aircraft on-site fault diagnosis and isolation.