Using Flux Compensator to Implement Direct Torque Control of Permanent Magnet Synchronous Motor at Low Speed Improvement

Abstract

The purpose of this research is to overcome the disadvantages of the classic direct torque control (Classic-DTC) in the switching table scheme. The approach is based on torque angle control, which is based on the relationship between the stator flux and rotor flux space vectors of the intuitive control system. DTC can achieve rapid torque response, which can cause high torque ripple and noise. In order to reduce stator flux ripple and torque ripple, the space-vector pulse width modulation (SVPWM) generates different switching states for each sampling time, and adapts to overcome the aforementioned problems, especially flux ripple and torque ripple. The reference flux is kept constant in this paper, and a fuzzy controller is used to compensate the reference flux in order to lessen the errors of the transient state response. In order to demonstrate this method, it was installed on a permanent magnet synchronous motor (PMSM) controller. Finally, the control system is implemented by digital signal processor TMS320F28335 to achieve high speed and accurate control of the system.