Comparative study of conventional DTC and DTC_SVM based control of PMSM motor — Simulation and experimental results

Abstract

In the conventional direct torque control (DTC) of a permanent magnet synchronous motor (PMSM), hysteresis controllers are used to choose the proper voltage vector resulting in large torque ripples, and the inverse voltage vector, employed in this system instead of the zero voltage vectors used in an induction motor, can accelerate the torque response but enlarges the torque ripples at the same time. To ameliorate the steady state effectiveness of the PMSM DTC system a SVM scheme is introduced in this paper. In the direct torque, control scheme using space vector modulation (DTC-SVM) for permanent magnet synchronous motor. The study of PMSM shows that the increase of electromagnetic torque is related to the increase of the angle between the stator and rotor flux linkages and therefore swift torque response can be obtained by increasing the rotating speed of the stator flux linkage as fast as possible. This paper presents a simulation and a practical implementation for the conventional DTC and the DTC-SVM based control of the PMSM, using a dSPACE-1104. To confirm the efficacy of the proposed technique, simulation and experimental results are presented. Besides, the system associated with these techniques can effectively decrease flux and torque ripples with better dynamic and steady performance. The results with the SVM technique show more performances than the results with the conventional DTC.