Torque Ripple Reduction in DITC-Based Switched Reluctance Motors Using Integrated ADRC and Repetitive Control

This study proposes a linear active disturbance rejection control and load-adaptive multi-harmonic repetitive control (LADRC–LAMHRC)-based direct instantaneous torque control strategy to improve the dynamic performance of a three-phase 6/4 switched reluctance motor. Although conventional proportional–integral-based direct instantaneous torque control (PI-DITC) provides satisfactory speed tracking, its performance is limited by pronounced torque ripple and reduced robustness under sudden load variations. In the proposed scheme, the LADRC estimates and compensates for lumped disturbances and model uncertainties, whereas the LAMHRC attenuates the periodic speed-error components associated with the torque ripple and generates an auxiliary torque-compensation command. The effectiveness of the proposed method was evaluated through comparative MATLAB/Simulink simulations with the conventional PI-DITC scheme. At reference speeds of 500 and 1000 r/min, the proposed controller reduced the torque-ripple coefficient from 11.11% to 2.96% and from 11.76% to 2.55%, corresponding to reductions of 73.4% and 78.3%, respectively. When the load torque was increased from 5 to 7 N·m, the maximum speed deviation decreased from 0.45 to 0.05 r/min, corresponding to an 88.9% reduction in maximum speed deviation. For a load reduction from 7 to 5 N·m, the speed deviation decreased from 0.5 to 0.1 r/min, corresponding to an 80.0% reduction. Under the investigated simulation conditions, the proposed scheme achieved a lower torque ripple and improved load disturbance rejection compared with the conventional PI-DITC scheme.