基于比例失效率退化模型的可靠性评估方法

针对不假定寿命分布类型的长寿命可靠性评估问题,提出一种不同于传统基于退化轨迹和退化量分布的退化数据可靠性评估方法。将时间视为类加速因子并作为协变量,通过引入比例风险模型来描述产品寿命与退化量失效率之间的关系,建立比例失效率退化模型;通过考虑分布簇之间的差异度来确定退化量分布类型,求出退化量基准失效函数及比例失效率系数;采用线性回归模型拟合出类加速模型参数估计,确定已知检测时刻下的退化量失效率函数,并外推产品在退化失效阈值下的寿命可靠度函数;结合实例分析,验证方法的实用性和有效性。

Method on reliability assessment based on proportional failure rate degradation model

Aiming at the problem of long lifetime reliability assessment in the assumption of unknown life distribution, a new method on reliability assessment for degradation data is proposed, which is different from the traditional method based on the degradation path and degradation measure distribution. Time is treated as a similar accelerated factor and used as a covariate. The relationship between the lifetime and the degradation failure rate of the product is described by the proportional hazard model and the proportional rate model is built. The degradation distribution is determined through the divergence of the distribution set， and the degradation basic failure rate function and its proportional rate coefficient are obtained. The linear regression model is used to evaluate the parameters of the similar accelerated model， and the degradation failure rate function in certain detection time points is determined. The lifetime reliability function of the product under the predetermined degradation failure threshold is obtained. An example is provided to demonstrate the validity of the proposed method.