高温高湿条件下薄膜电容器的寿命预测

Lifetime Prediction of Film Capacitors Under High-temperature and High-humidity Conditions

在高温高湿环境中,应用于交流的薄膜电容器在长期运行时存在电容量损失的现象,而这对电容器工作会造成不利影响。本文以聚丙烯薄膜电容器为对象,建立了薄膜电容器的高温高湿加速老化试验平台,得到了不同温度和湿度条件下的薄膜电容器的寿命数据。研究采用两参数Weibull分布模型描述薄膜电容器的寿命分布,基于Arrhenius模型和逆幂律模型对不同温湿度下薄膜电容器的寿命预测进行研究。结果表明:当温度和湿度升高时,相同时间内薄膜电容器电容量的下降幅度会随之增大,电容器寿命Weibull分布则向寿命减小的方向迁移。通过不同温湿度条件下的电容器试验样品寿命数据计算得到寿命模型参数,从而可以针对薄膜电容器进行寿命预测。

The capacitance loss of film capacitors for AC application is existed in long term operation in high temperature and high humidity environment,which causes adverse effect for the operation of capacitor.In this paper,the polypropylene film capacitor is taken as an object,the high temperature and high humidity accelerated aging test platform for the polypropylene film capacitor is established and the lifetime data of the capacitors under different temperature and humidity conditions is obtained.The two-parameter Weibull distribution model is used to describe the lifetime distribution of the film capacitor.And a lifetime prediction of the film capacitor under different temperatures and humidity conditions is studied based on the Arrhenius model and inverse power law model.It is shown by the result that the reduction amplitude of capacitance of the film capacitor increases with the increase of temperature and humidity within the same time.The Weibull distribution of capacitor life is shifted to the direction of life decrease.The lifetime model parameters are obtained by the life data of the capacitor prototype under different temperature and humidity conditions,thus the life of the film capacitor can be predicted.