Torque and Flux Ripples Minimization of Permanent Magnet Synchronous Motor by a Predictive-Based Hybrid Direct Torque Control

Abstract

This paper proposes a hybrid control strategy for a permanent magnet synchronous motor (PMSM) drive based on a finite-set predictive control (FS-PC). The most efficient mode of the control algorithm is found for the minimum torque and flux ripple in a steady state, with fast dynamic responses, as well as the conventional direct torque control (DTC), following the selection of an optimum voltage vector. The rationale of the proposed control method is that it is composed of DTC and a FS-PC. On the other hand, the optimization process is carried out using a combination of DTC and FS-PC. Compared with the conventional model predictive control methods, the proposed method adopts a measure like that of DTC to reach the optimal switching state of the inverter by minimizing the cost function. However, the method has a simple computational function for such a purpose. Taking into account the simulation and experimental results, it can be stated that the proposed method, which uses hybrid strategy, has high dynamic responses to the lower torque and the flux ripples with a simple structure and implementation, indicating the validity of this method for PMSM drive.