Simplified predictive control for direct torque control of surface permanent magnet synchronous motor

In order to suppress high torque ripple in the surface permanent magnet synchronous motor (PMSM) direct torque control based on switching table, predictive control with the angle of applied voltage vector as control variable is proposed. The amplitude of stator flux and torque at next sampling period were calculated. Furthermore, cost function about stator flux and torque's errors were obtained. The angle corresponding to the minimum cost function was selected as the angle of applied voltage vector. But the calculation of stator flux and torque were complicated and time-consuming. Therefore, simplified expressions to calculate stator flux and torque were given. Errors between simplified expressions and conventional expressions show simplified expressions can be used instead of conventional expressions. Simulation results of surface permanent magnet synchronous motor direct torque control using conventional and simplified predictive control show two control schemes can control stator flux and torque with good performance. Time consuming and calculation results of conventional and simplified predictive control expressions of stator flux and torque were carried out using MK60DN512ZVLQ10 chip. Experimental results show that, compared with conventional predictive control, simplified predictive control can decrease time consuming with the same calculation results. © 2020, Harbin University of Science and Technology Publication. All right reserved.