PWM-VSI Fault Diagnosis for a PMSM Drive Based on the Fuzzy Logic Approach

For the purpose of increasing the reliability in a hostile environment, techniques of fault diagnosis have been reported for a three-phase voltage-source inverter (VSI). Based on the average current Park's vector method, this paper proposes a fuzzy-based fault diagnosis method for the VSI in the three-phase permanent-magnet synchronous motor drive. By utilizing the phase current information, the fault symptom variables are calculated by using the average current Park's vector method. The fuzzy logic approach is applied to process the fault symptom variables and obtain the faulty information of power switches. Compared with other fuzzy logic methods, the fuzzy logic design, fuzzy inputs, and fuzzy rules are different. The proposed fault diagnosis method can detect and locate not only the single or multiple open-circuit faults, but also the intermittent faults in power switches, which can improve the reliability of the motor drive system. The effectiveness of the proposed method is validated by both simulation and experiments.