A DTC-SVM method with flux observer based on rotor position and current model for SPMSM control system

Conventional direct torque control (DTC) for permanent magnet synchronous motor (PMSM) has some shortcoming of more torque fluctuation, current fluctuation and inconstant switching frequency. Through an analysis of surface mounted permanent magnet synchronous motor (SPMSM), a new DTC-SVM (space vector modulation) method with a flux observer based on rotor position and current model, fast reference voltage generating modules and a torque regulator with variable proportional coefficient and integration control is proposed in the paper. It is derived that the proportion coefficient of the torque regulator changes with the actual torque. Its simulation model and experiment system were built up. The experiment results show that it has the advantages of the small current distortion, low torque ripple, rapid response with changes of input and good anti-interference performance.