Direct Torque Control of PMSM using hysteresis modulation, PWM and DTC PWM based on PI Control for EV - A comparative analysis between the three strategies

Abstract

This paper presents the direct torque control of a Permanent Magnet Synchronous Motor (PMSM) on Electric Vehicle (EV). The PMSMs are considered as the best choice for EV applications due to their high torque to inertia ratio, high efficiency, wide speed range, compact structure and low noise. The PMSM is a strongly coupled nonlinear system, application of DTC to PMSM motor drives offers a fast and accurate control. The basic DTC scheme may bring large amount of ripples in the output torque. This torque ripple can bring problems such as speed fluctuation and acoustic noise. In order to reduce the torque ripples a Pulse Width Modulation based DTC is introduced. The ripple content in torque output can be further reduced by applying a PI control based DTC PWM technique. The simulation results shows that the ripple content in the torque output was significantly reduced by using these techniques