Direct Torque Control of PMSM Based on Fractional Order Sliding Mode Variable Structure and Experiment Research

A direct torque control method based on fractional order sliding mode variable structure (DTC-FOSMVS) was proposed for the speed control of a permanent magnet synchronous motor (PMSM). The proposed method in which the space vector pulse width modulation (SVPWM) with fixed switch frequency is applied, reduces the torque and flux ripple, and improves the speed control performance. In order to improve the energy efficiency and reduce the demagnetization effect, the DTC-FOSMVS method with dynamic flux reference was designed. The stability of the control method is proved by Lyapunov theory. The performance of the proposed method is verified through experiment which is based on hardware in loop and Simulink/QuaRC real time control software. The experiment results show the robustness and effectiveness of the proposed method.