Diagnosis and Fault-Tolerant Control of Permanent Magnet Synchronous Motors With Interturn Short-Circuit Fault

In this brief, a hidden Markov model (HMM) is used to diagnose the severity of permanent magnet synchronous motors (PMSMs) with interturn short-circuit (SC) fault. The fault diagnosis result in this brief is an extension of similar result for dc motors. When the fault severity allows for continuing operation of the motor, a bisecting search method is proposed to reduce torque ripples while maintaining maximum torque capability. The advantages of the new fault-tolerant control (FTC) method over other existing methods in the literature are analyzed. Torque ripples are significantly reduced compared with the existing FTCs in the literature. The assumption of SC resistance equal to zero made in another paper was eliminated.