A modified direct torque control for PMSM under inverter fault

This paper introduces a fault tolerant inverter for a direct torque control (DTC) based permanent magnet synchronous motor (PMSM) system; this fault tolerant inverter changes to a four-switch three-phase inverter after a short-switch fault occurrence. A modified DTC method is proposed for this new drive system under inverter fault. The models of the after fault PMSM DTC system is analyzed, and the PMSM drive system based on both the traditional and modified DTC method are studied. The simulation results verify that the modified direct torque control method and the fault tolerant inverter ensure the high reliability and continuously operation of the PMSM DTC system under inverter fault.