关键词: 实时可靠性评估, 维纳过程, 期望最大化算法, 贝叶斯方法, 金属化膜电容器

Abstract: With respect to Wiener process-degradation products,a method which fused prior degradation information,life data information and current degradation data was proposed to assess their reliability.Firstly, on the basis of the prior degradation information and the life data information,parameters'prior distributions were established by EM method;secondly,by using Bayesian method,prior distributions could be updated to posterior distributions;then the reliability was evaluated based on the posterior distributions.The proposed method can update the reliability evaluation results whenever new degradation data is available,so it is suitable for real-time reliability assessment.Finally,the validity and practical value of this method is verified by an example,relating to reliability assessment of the metallized film capacitor.

Key words: real-time reliability assessment, Wiener process, expectation-maximization(EM) algorithm, Bayesian method, metallized film capacitor