Study on direct torque control algorithm based on space vector modulation

Aiming at the problem of high flux and torque ripples appeared for its variable switching frequency of the traditional direct torque control (DTC) scheme with a pair of hysteresis comparators to control motor stator flux and electromagnetic torque, a kind of direct torque control with space vector modulation (DTC-SVM) was scheme presented. The double closed-loop flux and torque PI control arithmetic was established based on the mathematical model of induction motor. Treat flux and torque as control variable, vector control continuous smooth, constant switching frequency and direct torque control fast response characteristics were absorbed. Simulation and experiment results show that the flux and torque ripples decreased greatly, the static and dynamic performance of the system was improved when the DTC-SVM scheme in constant switching frequency compared with the traditional DTC, and the correctness and feasibility of this method are verified.