Application-Oriented Power Semiconductor Switches Condition Monitoring Based on Data-Driven Method

This paper proposes an application-oriented condition monitoring method for power semiconductor switches, which constructs a robust health indicator with high robustness, low sampling rate, and low data storage requirements that decouples the effect of operation conditions on the health indicator. First, an effective application-oriented data acquisition and collection strategy is presented based on high-level synchronous-triggered sampling of the switching cycle and data selected from the peak point of the fundamental cycle current, which retains features strongly correlated with the degradation of power semiconductor switches while reducing sampling rate, data transmission and storage requirements. Then, a concept of mission profile alignment method is proposed to decouple the effects of operation conditions on the health indicator. It avoids the extensive offline calibration requirement that is difficult to be applied in the field. Finally, the reconstruction error of the conditional autoencoder network is used as a robust health indicator, which further enhances the immunity of condition monitoring against variations of operation conditions. A case study with the three-phase grid-connected inverter for the PV system is demonstrated to prove the effectiveness of the proposed method.