基于有向图模型的民机航空电子系统故障诊断

结合民机航电系统外场可更换单元或模块（LRU/LRM）的故障模式及影响分析（FMEA）、故障树 分析和实时性要求，设计了基于时间故障传播图（TFPG）的系统故障诊断元模型和领域模型，研究了基于逻 辑和时间一致性检验的故障诊断算法，使用后向推理和可信度度量列出候选故障集。以飞行管理系统为例，构 造了其功能失效的TFPG 模型，并通过仿真验证了基于TFPG 的诊断在滤除级联效应和关联驾驶舱效应中的有 效性。

A Directional-Graph-Based Method of Fault Modeling for Civil Avionics Systems

According to failure mode and effects analysis (FMEA) of related line replaceable units and modules(LRU/ LRM)of civil aircrafts, fault tree analysis and real-time requirements, the system fault diagnosis meta model and domain model based on Timed Failure Propagation Graph (TFPG) are designed. The fault diagnosis algorithm based on logical and temporal consistency is studied. Using the algorithm of backward inference, the fault candidates are listed on the basis of measurements of plausibility. The directed graph model of functional failures of a flight management system is constructed. The result of simulation shows the effectiveness of TFPG-based diagnosis in FDE relating and cascading effects removal.