A Novel Mixed-Effect Model for Multi-Stress Accelerated Life Test Evaluation

Multi-stress accelerated life test can be used to solve the life prediction problem of high reliability products in composite environment. The multi-stress accelerated model plays a key role in the multi-stress accelerated life test. Because the damage caused by different environmental stresses to products is not a simple linear superposition, the correlation between different acceleration stresses should be considered. However, most of the multi-stress acceleration models remain in the two-stress model and do not consider the correlation between the stresses. To overcome this problem, we develop a mixed-effect multi-stress acceleration model to consider the correlation between stresses. Then a parameter estimation method based on EM algorithm is proposed and lifetime prediction is calculated. Finally, a real case of intelligent electric meters is used to demonstrate the superiority of the proposed model and method.