Adaptive Vector Magnitude Modulation for Torque Ripple Minimization in Direct Torque Control of Induction Motors

Abstract

This paper presents an advanced Direct Torque Control (DTC) method for induction motors aimed at minimizing torque ripple. Traditional DTC techniques and virtual vector-based DTC methods rely on fixed vector magnitudes, irrespective of the torque error's severity, leading to significant torque ripple and complex switching lookup tables. The proposed method introduces a real-time adaptive vector magnitude modulation strategy, where the vector magnitude is continuously adjusted based on the instantaneous torque error. This ensures proportional vector injection corresponding to the real-time torque error, improving torque control precision. Furthermore, the proposed approach reduces the size and complexity of the switching lookup table. To validate the effectiveness of the proposed method, simulations are conducted in MATLAB/Simulink environment. Comparative analysis with conventional DTC schemes and a multi-magnitude vector approach demonstrates substantial reductions in torque ripple while simplifying the control implementation.