An Improved Model Predictive Direct Speed Control with Synchronous Prediction and Weight Factor Optimization for PMSM Application

In permanent magnet synchronous motor (PMSM) application, model predictive direct speed control is usually utilized to eliminate cascade loop structure existed in traditional vector control. However, asynchronous prediction equation (ASPE) with one-step delay is mostly required to achieve optimal voltage vector to drive the PMSM motors, which exist the problem of asynchronous prediction of speed and current. It is shown that in this paper the synchronous prediction equation (SPE) does not have the prediction delay, but it cannot realize the speed tracking control. Aim to solve the above problems, an improved PMSM model predictive direct speed control with synchronous prediction and Weight factor optimization is proposed in this paper. Firstly, the Taylor synchronization prediction equation (TSPE) is used to realize the speed and current prediction synchronization and the speed tracking control. Secondly, in order to improve the response speed of the system, a quadratic cost function considering the weight factor optimization is used for cost evaluation, and the Lyapunov direct method is used to design the weight factor with taking into account the stability and rapidity of the system. Finally, in order to verify the effectiveness of the proposed method, the MATLAB simulation and hardware-in-the-loop experiments are carried out. The results show that the proposed control method achieves predictive synchronous between speed and current, fast and stable speed tracking control, and the setting time is faster than the ASPE, and the TSPE without considering the weight factor.