基于T-S模糊故障树的下滑信标故障诊断分析

Fault Diagnosis of Glidepath Beacon Using T-S Fuzzy Fault Tree

为解决实际仪表着陆系统下滑信标(glidepath beacon, GP)故障时无法快速定位故障点的难题,提出基于T-S(Takagi-Sugeno)模糊故障树的故障诊断方法。通过对GP系统进行不同功能系统的划分,进行T-S模糊建模,为每个板件的故障可能性进行模糊数赋值,计算故障程度的隶属度,实现复杂系统的定量计算。建立起两种计算方法,分别为根据系统各板件的故障可能性及根据各板件当前的故障程度来计算系统的故障可能性。经对比,计算结果与实际情况相符,第一种算法适用于简单系统或复杂系统板件的故障诊断,第二种算法适用于大多数系统。可见此法在GP故障诊断方面具有有效性。

In order to solve the problem that the glidepath beacon(GP)of the instrument landing system cannot quickly locate the fault point when it fails,a fault diagnosis method based on T-S fuzzy fault tree was proposed.Firstly,GP system was divided into subsystems with different functions,and T-S fuzzy modeling was carried out for each subsystem.Secondly,a fuzzy number was assigned to the fault possibility of each panel in the system,and then its fuzzy membership degree was calculated according to the fault degree of each panel.Finally,the fault possibility of complex system was calculated quantitatively.Two calculation methods were established,which were to calculate the failure probability of the system according to the failure probability of each board part of the system and the current failure degree of each board part.After comparison,the calculation results were consistent with the actual situation.The first algorithm is suitable for the fault diagnosis of simple systems or complex system boards,and the second algorithm is suitable for most systems.It can be seen that this method is effective in GP fault diagnosis.