Analysis and Diagnosis of Power Converter Faults in Switched Reluctance Motor Drives

Power converter faults can result in malfunction or damage to motor windings and insulation due to unintended current flow within the motor. To avoid such damages the diagnosis of a power converter fault is very crucial. This article presents a simple, fast, and online fault diagnosis scheme using reference current signals. The proposed method utilizes the reference current signal adjusting unaffected phases through the controller to restore to its operation with reduced performance when fault occurs. This paper analyzes the characteristics of the reference current signals upon open- and short-circuits of the switched. By the observations made on the switch and its corresponding phases and accordingly, diagnosis performance is undertaken. The changes observed in the reference current signals were observed and expressed in the fault characterization. The proposed method better recognizes diagnosis under varying load torque and speed conditions. The above scheme verification was conducted with the simulations on a 4-phase 8/6 SRM drive system in MATLAB/Simulink environment.