基于Wiener过程的万能式断路器附件剩余寿命预测*

万能式断路器作为一个复杂的机械系统,其操作附件的剩余寿命预测对于维护断路器的可靠性至关重要。为准确掌握操作附件剩余寿命情况,提出了一种基于Wiener过程的万能式断路器操作附件剩余机械寿命预测方法。首先,通过对操作附件动作过程中线圈电流波形的分析选取了动作时间作为性能退化特征量;其次,考虑到断路器操作附件性能退化过程具有线性非单调的特点,采用Wiener过程建立了操作附件的性能退化模型,并利用极大似然估计法对退化模型参数进行估计;然后,基于首达时间的概念建立了剩余寿命预测模型,推导出剩余寿命概率密度函数解析式。最后对安装于万能式断路器上的分励脱扣器和释能电磁铁两种操作附件进行全寿命试验及其剩余寿命预测,预测结果验证了所提方法的有效性。

Remaining useful life prediction of accessories for the conventional circuit breaker based on Wiener process

The conventional circuit breaker is one kind of complex mechanical system. The remaining useful life (RUL) prediction of its operating accessories is essential for maintaining the reliability of the circuit breaker. To accurately grasp this RUL, this article proposes a remaining mechanical life prediction method of operating accessories for the conventional circuit breaker based on Wiener process. First, the action time of operating accessories is selected as the performance degradation feature by analyzing the coil current waveform during the operation process of the operating accessories. The performance degradation process of operating accessories is linear and non monotonic. Hence, the performance degradation model is established by employing Wiener process. The maximum likelihood estimation method is utilized to estimate the parameters of the degradation model. Then, based on the concept of first hitting time, RUL prediction model is formulated and its probability density function is derived, which realizes the RUL prediction of operating accessories. Finally, the whole life tests and the RUL prediction for the shunt release and the release electromagnet as operating accessories installed in the conventional circuit breaker are carried out. The prediction results demonstrate the effectiveness of the proposed method.