Direct torque control for permanent magnet synchronous motor with optimal duty cycle control

Aiming at the torque ripple in direct torque control for permanent magnet synchronous motor (PMSM), a direct torque control (DTC) with optimal duty cycle control method is proposed on the basic of analyzing the reason of torque ripple in traditional direct torque control. The duration time of active voltage vector is calculated with the idea of predictive control based on the error of torque and flux in the next control period, and the direct torque control with duty cycle control controller is designed. Theoretical analysis, simulation and experimental results show that the proposed method can reduce torque and flux ripple effectively without affecting the dynamic and improve the torque steady state, compared with the traditional direct torque control. ©, 2015, The editorial office of Transaction of China Electrotechnical Society. All right reserved.