Construct a Fuzzy Rule Table with the Direct Torque Control Principle

Direct torque control (DTC) is one of the popular induction motor control structures in the industry. This control structure is simple, flexible, and high performance. However, large torque ripple and poor performance in low speed regions are disadvantages of this structure. Therefore, overcoming these disadvantages of the DTC structure is always an issue of concern in the field of motor control. In order to address the drawbacks of the conventional DTC structure, this paper investigates the DTC structure employing a fuzzy controller (FDTC). The fuzzy controller in this structure will replace the stator flux controller, torque controller, and switching table in the classic DTC structure. The paper proposes fuzzy rules are built based on the principle of direct torque control and are derived from the DTC table in 12 sectors. This ensures the stability and robustness of the FDTC control structure. Simulation results on Matlab/Simulink show that the fuzzy rules suggested in this paper, when combined with the FDTC structure, perform exceptionally well and the torque ripple and stator flux ripple are significantly reduced compared to the traditional DTC structure. Furthermore, even at low speeds, FDTC has a strong dynamic responsiveness.