Direct Torque Control of PMSM with Modified Finite Set Model Predictive Control

Guangqing Bao,Ting He,Wugang Qi

doi:10.3390/en13010234

Guangqing Bao, Ting He + Show 1 more

Open Access

https://doi.org/10.3390/en13010234

Copy DOI

Abstract

A direct torque control (DTC) with a modified finite set model predictive strategy is proposed in this paper. The eight voltage space vectors of two-level inverters are taken as the finite control set and applied to the model predictive direct torque control of a permanent magnet synchronous motor (PMSM). The duty cycle of each voltage vector in the finite set can be estimated by a cost function, which is designed based on factors including the torque error, maximum torque per ampere (MTPA), and stator current constraints. Lyapunov control theory is introduced in the determination of the weight coefficients of the cost function to guarantee stability, and thus the optimal voltage vector reference value of the inverter is obtained. Compared with the conventional finite control set model predictive control (FCS-MPC) method, the torque ripple is reduced and the robustness of the system is clearly improved. Finally, the simulation and experimental results verify the effectiveness of the proposed control scheme.

Highlights

Permanent magnet synchronous motor (PMSM) direct torque control (DTC) has been widely used in industry due to its simple control structure, fast dynamic response, and high efficiency [1]
A new scheme of direct torque control for permanent magnet synchronous motor (PMSM) based on a finite control set (FCS)
Through the analysis of the above experiments, compared with the conventional finite control set model predictive control (MPC) (FCS-MPC) control system, the proposed FCS-MPC in this paper effectively reduces the torque ripple and improves the following performance of the motor torque

Summary

Introduction

Permanent magnet synchronous motor (PMSM) direct torque control (DTC) has been widely used in industry due to its simple control structure, fast dynamic response, and high efficiency [1]. An improved method is calculating the effective voltage vector action time in real time to ensure the minimum torque ripple by the current torque error [4,5,6]. This method reduces the torque ripple to a certain extent, but the calculation process is complicated. Voltage space vector modulation (SVM) is introduced into DTC [7,8] This method can effectively reduce the torque ripple, but it cannot eliminate the steady-state error of the torque. The calculation process is highly dependent on the parameters of the motor and has poor robustness

Methods

Results

Conclusion