基于UGF-GO法的EWIS退化系统可靠性分析

针对飞机电气线路互联系统（EWIS）差异性大、随时间退化严重、可靠性建模困难等问题，将通用生成函数（UGF）和GO法融合，提出了基于UGF-GO法的EWIS退化可靠性分析方法。首先，考虑EWIS各连接部件使用性能及环境的差异性，利用含随机参数的Wiener退化过程模型建立部件可靠性仿真模型，采用马尔可夫链蒙特卡罗（MCMC）算法对模型中的未知参数进行估计，并与传统二步法参数估计值进行对比，得到较为精确的系统部件退化可靠性曲线。其次，在分析系统退化可靠性时，利用UGF-GO法对某飞机EWIS结构可靠性进行建模及计算。最后，以某飞机电气线路互联系统为例，结合部件退化可靠性计算结果，评估系统在不同给定阈值下可靠性水平。结果表明:UGF-GO法可有效解决系统退化状态的可靠性分析问题。 

Degradation system reliability analysis of EWIS based on UGF-GO methodology

In view of several problems of electrical wiring interconnection system (EWIS), such as condition difference, ageing phenomenon and modelling difficulty, a UGF-GO methodology based EWIS degradation reliability analysis method is proposed by combining traditional GO methodology and universal generating function (UGF). In this paper, based on the difference of performance and environment of system components, using Wiener degradation process model with random parameters, the component reliability simulation model has been built. Markov chain Monte Carlo (MCMC) algorithm is used to estimate parameters in the model. The simulation test show that MCMC algorithm improves the estimation accuracy compared to the parameter estimation values of traditional two-step method. In analyzing the reliability of a degenerate system, the UGF-GO methodology works for calculating the EWIS reliability. Finally, the EWIS of an aircraft is taken as an example, and combined with the reliability calculation result of components, the reliability level of EWIS is evaluated under different thresholds. The results show that UGF-GO methodology can effectively solve the reliability analysis problem of the deteriorating system.