New SVPWM Used Post a Two-Phase Failure in FOC Five-phase PMSM Drives

Abstract

One of the pronounced features of the multi-phase machines compared to the conventional three-phases machine is their high-fault capability. This merit is quite important as it contributes to minimizing the number of interruptions in industrial operations. This paper introduces two new Space Vector Pulse Width Modulation Techniques (SVPWM) to be used with the Field Oriented Control (FOC) strategy under two phases failure of the five-phase motor drives. The first SVPWM technique can be used if the failure happens to the adjacent phases while the second one is used in the cases that the failure happens to non-adjacent phases. The proposed modulation techniques are considering the modifications of the remaining healthy stator currents of the five-phase motor under the failure of the two adjacent phases and non-adjacent phases to maintain the torque producing Magneto Motive Force (MMF) and hence maintain the speed. This will enhance the reliability of the whole drive system. Also, the new SVPWM techniques will reduce the harmonics in the currents and hence reduce the ripple in the torque. Simulation results illustrate the capability of proposed new SVPWM techniques to maintain the torque ripple less than 3.6 % and 3.4% post the failure in adjacent phase and non-adjacent phases respectively.