Reduced-Order Fractionalized Controller for Disturbance Compensation Based on Direct Torque Control of DSIM With Less Harmonic

Abstract

This paper proposes a new design of a speed regulator loop based on a reduced-order fractionalized proportional-integral controller (ROFrPI) for direct torque control (DTC) of a dual-star induction motor drive with less harmonics in order to improve speed and electromagnetic torque responses. The developed approach employs a modified switching table of DTC to control the stator flux in the harmonic subspace and eliminate circulation currents and therefore obtain purely sinusoidal current form. The effectiveness of the proposed configuration has been tested under various operating conditions by evaluating transient speed and torque responses. Moreover, a comparative investigation has been carried-out to evaluate the performance of the proposed ROFrPI controller for five fractional-order integrator values using the Matsuda approximation. For this, the obtained results demonstrate that the proposed controllers in the speed regulator loop exhibit high performance and better resilience than the conventional controller in terms of overshoot, settling time, and rise time for speed and torque.