A New Method for Detecting Short-circuit Faults in Power Converter of Switched Reluctance Generator

Abstract

As a key element of switched reluctance generator (SRG), power converter is a relatively weak part in comparison with the other components. Focusing on the conventional asymmetric half-bridge (AHB) converter in SRG, a diagnosis method for short-circuit faults of main power switches, such as MOSFETs, is proposed based on theoretical analysis and simulation in this paper. Per-unit value of direct-current (DC) component in each phase current is calculated based on DC components of all phase current and excitation current, which are acquired with moving average filter (MAF), and the per-unit values calculated above are taken as characteristic values indicating short-circuit (SC) faults of main power switches. All faults are diagnosed and located by comparing characteristic value of each phase and judging their states. Validity and rapidity of the proposed method are verified with results of the experiments.