Short-Circuit Fault-Tolerant Control of Dual Three-Phase PM Machines Utilizing Single Current Compensator

During the short-circuit fault, the interaction between short-circuit current and back electromotive force of shorted turns induces braking and second-order harmonic components on electromagnetic torque. However, the above distortion terms are ignored in normal control, resulting in degraded torque performance. To this end, this paper proposes a simple quadrature axis current feedforward compensator based on the principle of undisturbed torque for short-circuit fault-tolerant operation of dual three-phase permanent magnet machine. Compared to existing methods, it avoids the injection of unnecessary currents to direct axis, thereby minimizing the stator copper loss. Experimental results are given to verify the effectiveness of the proposed fault-tolerant control.