철도차량용 3-level ANPC 인버터의 DC 커패시터 고장 진단을 위한 ESR 측정 방안의 적용 효과 연구

Abstract

This paper studies the effect of applying the ESR measurement method to diagnose DC-link capacitor failure of 3-level ANPC inverter for railway vehicles. Inverters use DC-link capacitors to keep the voltage constant, which is the factor with the highest failure rate compared to other components used in inverters. Accordingly, in this paper, in order to find a way to monitor the failure of the DC-link capacitor, ESR measurement methods were analyzed, and the effect was analyzed through a simulation experiment applied to a 3-level ANPC inverter. As a result, when measuring ESR by designing an analog filter using Op-Amp, the RMS-based ESR measurement method is effective. Conversely, when measuring ESR using digital filters, it is judged to be more effective to use the AC coupling-based ESR measurement method.