两阶段非线性Wiener过程退化建模与可靠性分析

基于性能退化数据对产品进行可靠性分析一直是可靠性工程领域研究的热点与难点。针对多阶段退化过程中存在的非线性规律,同时考虑变点位置位于测试时刻之间的一般情形且各试样变点存在个体差异性的实际情况,提出了基于Wiener过程的两阶段非线性退化模型,给出了模型参数极大似然估计方法,建立了可靠性分析和寿命预测方法。最后通过高压脉冲电容器实例的对比分析,验证了所提方法的合理性与有效性。结果表明,与多阶段线性Wiener过程方法相比,所提方法能够更加准确地描述退化过程的非线性时变特征,进而得到更为合理的寿命评估结果。

Two-phase nonlinear Wiener process for degradation modeling and reliability analysis

Reliability analysis based on product degradation data has become a research focus and a difficult topic in the field of reliability engineering. A two-phase nonlinear degradation model based on the Wiener process is proposed. It can reasonably consider the commonly encountered situation where a change point locates between the test time, and specific properties of each unit are shown regarding the change point. Then a maximum likelihood parameter estimation method is given. Reliability analysis and lifetime prediction methods are constructed. Finally, the reasonability and effectiveness of the methods are validated by a comparative analysis regarding high voltage pulse capacitors. The results show that the proposed model can describe the nonlinear time-varying properties illustrated by the degradation process more accurately than the multi-phase linear Wiener process model, and then more reasonable lifetime assessment results can be obtained.