Predictive Control of Surface PMSM Direct Torque Control System using Voltage Vectors with Variable Angle

Abstract

Based on flux and torque’s expressions of surface permanent magnet synchronous motor (PMSM) direct torque control (DTC) system, values of stator flux and torque at next sampling point after applying voltage vector with different angle are given in this paper. The objective function is proposed which aims to minimize stator flux and torque’s error. The predictive control will select the optimal angle corresponding to the minimum objective function. Simulation results show the surface PMSM DTC system under the predictive control works properly. The predictive control selects the optimal voltage vector from aggregate of voltage vectors with different angle. More selectable voltage vectors will lead to better control performance, but it will cause heavier calculation burden. In this paper, control performances of surface PMSM DTC system using different aggregates of voltage vectors are studied. Considering control performance and calculation burden, an ideal aggregate of voltage vector is given.