基于加速退化试验的漏电信号调理电路性能退化及可靠性研究

Performance degradation and reliability of leakage signal conditioning circuit based on accelerated degradation test

在电子电路服役过程中,元器件退化会引起电路输出特性变化,降低电子电路的可靠性。漏电信号调理电路作为一种电子电路,其可靠性直接决定了漏电断路器的可靠性。以漏电信号调理电路为研究对象,首先基于灵敏度分析方法确定影响电路性能退化的关键元器件,并对漏电信号调理电路进行了以温度为加速应力、动作电流值为退化特征量的恒定应力加速退化试验;其次根据不同温度应力下的试验数据建立基于Wiener过程的漏电信号调理电路性能退化模型,并利用极大似然估计法求取退化模型的未知参数,进而得出寿命预测的概率密度函数和可靠度函数;最后利用阿伦尼斯(Arrhenius)方程外推出正常应力下漏电信号调理电路的预测寿命。相关结论可为不同电子电路的寿命预测及可靠度分析提供支撑。

During the service life of electronic circuits,the degradation of components will change circuit output performance,thus leading to low reliability of electronic circuits.As an electronic circuit,the reliability of the leakage signal conditioning circuit directly determines the reliability of the leakage circuit breaker.The signal conditioning circuit of residual current device was researched.Firstly,the key components which affect circuit performance degradation were determined based on the sensitivity analysis method,and the constant stress accelerated degradation test was carried out for the leakage signal conditioning circuit with temperature as accelerated stress and tripping current as degradation feature.Secondly,according to the test data under different temperature stress,the performance degradation model of signal conditioning circuit based on Wiener process was established.The unknown parameters of degradation model were obtained by using maximum likelihood estimation method,and then the probability density function and reliability function of life prediction were obtained.Finally,the predicted life of signal conditioning circuit under constant stress was derived from the Arrhenius equation.The conclusion can provide guidance for life prediction and reliability analysis of different electronic circuits.