Decoupled Speed and Flux Control of Three-Phase PMSM Based on the Proportional-Resonant Control Method

Abstract

Field-oriented control (FOC) has achieved great success in permanent magnet synchronous motor (PMSM) control. For the PMSM drive, FOC allows the motor torque and flux to be controlled separately, which means the torque and flux are decoupled from each other. Since the torque control is achieved by the speed controller, it can be considered that the speed and the flux of the PMSM are also decoupled from each other and can be controlled separately. In this paper, we propose a PMSM vector control using decoupled speed and flux controllers based on the proportional-resonant (PR) control method. A flux controller is proposed to control the flux of the PMSM and generate the d-axis reference current, whereas the speed regulator is used to generate the torque as well as the q-axis reference current. The PR controller is proposed to control the dq-axis currents and generate the reference voltages; its design is included.Therefore, decoupled speed and flux controllers are controlled separately using the PR controller. The Matlab/Simulink environment is utilized for the simulation, while the dSPACE DS1104 is used for the experimental work. The proposed control method is simple; there are no flux or torque estimators required, so it can avoid the complexity of estimators in the control scheme. The motor is tested under different scenarios, including flux change, speed change, and load torque change. The simulation and hardware results show the effectiveness of the proposed control method in controlling the the speed and the flux of PMSM with fast motor response and good dynamic performance in the different scenarios.

Keywords

• decoupled control
• flux controller
• PMSM
• proportional-resonant
• speed control
• vector control