Sensorless control of five-phase PMSM drives post the failure in two phases

This paper introduces a novel technique to maintain the operation of the five-phase permanent magnet synchronous motor post the failure in two phases of the motor and post the failure of the speed sensor occurs simultaneously. To achieve that, firstly, a fault-tolerant control (FTC) technique is implemented. The FTC is based on implementing two new space vector pulse width modulation (SVPWM) besides using field-oriented control to minimize the torque ripple and to maintain the performance post the two-phase failure. Secondly, algorithms are proposed to obtain the saliency position post the failure of the two phases. The technique is based on measuring the transient response of the motor’s remaining healthy currents due to the inverter switching actions. These switching actions are related to the PWM signals obtained from the new SVPWM techniques implemented post the two-phase failure. The whole control technique post the failures is very simple to implement. Simulation results are provided to verify the reliability of the proposed control technique to maintain the performance of the five-phase motor drive post the failure in the two phases and the failure of the speed sensor occurred simultaneously without compromising the preperformance (maintain the torque ripple less than 3.6% and 3.4% post the failure). Moreover, the results have demonstrated the ability for the whole system to work effectively over a wide speed range and load conditions post the failure.