Accelerated Degradation Test and Performance Degradation Characteristics of Intelligent Circuit Breaker Control Circuit

With the development of intelligent grid systems, smart circuit breakers are widely used. The control circuit is the core component of the smart circuit breaker, making its performance degradation characteristics highly significant. This paper focuses on the control circuit’s accelerated degradation test and performance degradation characteristics. First, an accelerated degradation test is designed, and a test platform is established. By analyzing the degradation mechanism of the intelligent circuit breaker control loop, the key weak links in the control loop are determined, and then the monitoring quantity is determined. Then, degradation data are preprocessed to extract features from the time, frequency, and wavelet domains. The multidimensional evaluation index model is applied to select the optimal features, fit the degradation trend, and use the fixed segmentation algorithm to divide the degradation stages and analyze the performance degradation characteristics of the control circuit. The experimental results show that the turning points of the two-stage degradation process at 85 °C, 95 °C, and 105 °C are 78.8%, 77.6%, and 77.0%, respectively. The position of the turning point is relatively fixed. The key circuit’s PSpice simulation model is built to verify the two-stage nonlinear characteristics observed in the experimental results. Finally, the results are verified by the Pearson correlation coefficient. The results show that the Pearson correlation coefficient between the simulation and accelerated life test results is above 0.9158, and the consistency between the two is high.