Fault Diagnosis of Output-side Diode-Bridge in Isolated DC-DC Series Resonant Converter

Abstract

This paper proposes a short-circuit fault (SCF) diagnosis strategy of the diodes in the full-bridge rectifier (FBR) of the series resonant converter (SRC). The diagnosis signal comprises only the voltage of the bottom diodes beside the switching signals of the front-end full-bridge inverter. The short-circuit fault can be immediately remedied after detection Without identification of the faulty diode. The active full-bridge in the input side of the SRC is reconfigured to operates as a half-bridge inverter, while the output-side rectifier operates as a voltage doubler after detecting the SCF. In this way, the output voltage of the converter remains constant, and the converter continues its operation. The simulation results obtained using PSIM software revealed that the fault can be identified and remedied within one switching period, and the converter continues operating even with a faulty component.