Investigation of short-circuit fault in a fault-tolerant brushless permanent magnet AC motor drive with redundancy

Short-circuit faults are the most serious faults in a fault-tolerant permanent magnet AC motor drive with redundancy. In this paper the effect of short-circuit faults on the output electromagnetic torque and torque ripple is examined and the fault analysis shows that the output torque will be reduced significantly and the torque ripple will be increased after short-circuit faults. One fault remedial strategy is proposed to compensate the torque loss due to the short-circuit faults. The experimental setup is developed and the experimental results are provided to verify the analysis results and the validity of the proposed fault remedial strategy.