Research On The Direct Torque Control For Permanent Magnet Synchronous Motors Using Space Vector Modulation

First of all, mathematical model of PMSM is presented after studying physical equations and equivalent circuits, and analyzed the principle of DTC. PU model of PMSM is also given for digital control of motor.To take full advantages of Direct Torque Control, a novel direct torque control of PMSM based on observing error of stator flux linkage is proposed.It can realize continuous voltage vector modulation and decrease the torque ripple.This scheme is validated by simulating and experimental results of PMSM DTC-SVM servo system.At the same time, the feasibility of sensor less operation for PMSM DTC is analyzed and a speed estimation scheme is proposed.On the basis of theoretic analysis and simulation, the hardware and software are designed for the digital signal processor (DSP)-based system. Furthermore, the DSP-based DTC control system platform for PMSM is designed. The debugging of hardware and software is completed in this paper and the DTC strategy is carried out in the software.