A novel static fault diagnosis approach for three-phase full-bridge inverter

This paper presents a novel fault diagnosis approach for three-phase full-bridge inverter, which is the most popular used in the brushless DC motor (BLDCM) system and the permanent magnet synchronous motor (PMSM) system. The short or open circuit fault diagnosis of the six power switches of the inverter is accomplished by only four simple resistor divider networks and one sampling resistor. By comparing the divided voltages with the reference voltage, the faults are detected and identified under a set of special judgment rules. The proposed method is designed to be used before system running. Compared with the existed methods, the proposed approach works with only weak current passing, which is more safe. Finally, the effectiveness is verified by simulation.