A New Scheme to Direct Torque Control of Interior Permanent Magnet Synchronous Machine Drives for Constant Inverter Switching Frequency and Low Torque Ripple

This paper presents a new direct torque control (DTC) scheme based on space vector modulation (SVM) for interior permanent magnet synchronous machine (IPMSM) drives. The new scheme provides a variable option for the improvement of DTC controlled IPMSM. Closed-loop control of both torque and flux is developed with two proportional-integral (PI) controllers. The stator voltage is generator through SVM unit. The torque and flux ripples are greatly reduced with fixed inverter switching frequency comparing with classical switching-table based DTC scheme. The analysis of the control principle provides a guide to design the controller parameters. Modeling results confirm the effectiveness of the proposed scheme