Study on DTC-SVM of PMSM based on propeller load characteristic

This paper analyzed the mathematical model of permanent magnet synchronous motor (PMSM), which is used as the propulsion motor in ship electric propulsion systems. Aiming at the problems of bang-bang direct torque control (DTC) applied to PMSM, such as the singularity of basic voltage space vectors available for selecting, large torque ripple and inconstant inverter switching frequency, a novel control method using space vector pulse width modulation (SVPWM) was proposed and a SVPWM module was designed. Then, a DTC-SVM model of PMSM was founded based on the MATLAB/Simulink. Finally, the validity of the speed control performance of propulsion motor with propeller load was verified by simulation The results indicate that DTC-SVM can reduce torque ripple greatly and have good response performance in the process of start and speedup.