Direct torque control of asynchronous motor based on space vector modulation

In conventional direct torque control (DTC) strategy, the inverter switching frequency is not fixed, torque ripple and total current harmonic distortion is high. In order to overcome these problems, improved DTC using space vector pulse width modulation strategy (SVPWM-DTC) is proposed in this paper. Switching table is replaced by SVPWM module to enable the fixed switching frequency. On the other hand, PI controllers are used to regulate the stator flux and torque errors. The simulation results verify the system is accuracy and feasibility.