加速应力下随机退化设备剩余寿命预测方法

A Remaining Useful Lifetime Prediction Method for Stochastic Degradation Device Under Accelerated Stress

针对步进加速退化试验中具有性能退化趋势的随机退化设备,采用非线性Wiener过程,建立与设备退化特征相符的步进加速退化模型;采用极大似然估计(MLE)法,求解出先验参数估计值;利用目标设备当前监测数据,基于贝叶斯方法更新随机系数后验分布;利用全概率公式,推导考虑随机系数估计不确定性的设备剩余寿命分布;通过算例分析验证了所提方法的正确性和优势。

Aiming at the stochastic degradation device with performance degradation trend in the Step-Stress Accelerated Degradation Test(SSADT)a nonlinear Wiener process is used to establish a step-accelerated degradation model consistent with the degradation characteristics of the device.The Maximum Likelihood Estimation(MLE)algorithm is used to obtain the estimates of prior parameters.The current monitoring data of the target device is used to update the posterior distribution of random coefficients based on Bayesian method.The Remaining Useful Lifetime(RUL)distribution of the device considering the uncertainty of random coefficient estimation is derived by using the full probability formula.The correctness and superiority of the proposed method are verified by an example.