Improved SVPWM fault-tolerant control of five-phase PMSMs based on generalized zero-sequence current torque ripple suppression

Five-phase permanent magnet synchronous motors (FPMSMs) are widely utilized in all-electric aircraft brakes, marine propulsion systems, and other high-reliability applications due to their excellent faulttolerance performance. Due to the asymmetry of the motor phase structure after an open-fault, pulsation of the output torque is inevitable. For this reason, an improved space voltage vector pulse width modulation (SVPWM) strategy is introduced to suppress the pulsation component in the output torque and realize smooth operation of FPMSM during single-phase open-circuit fault. First, this study analyzes the basic mathematical model of the FPMSM, and obtains the optimal reference current of the non-faulty phases according to the principle of equal copper loss and the principle of maximizing the DC bus voltage utilization. On this basis, an improved SVPWM algorithm based on generalized zero-sequence current tracking control is proposed to suppress the violent zero-sequence torque pulsation component. Simulation results show that the proposed fault-tolerant control method can effectively reduce the torque pulsation and realize high-quality operation of the motor after a fault.