Improved DC Motor Speed Regulation and Disturbance Rejection via Fractionalized PID Control Using the Optimal Fractional-Order System Approximation Method

Abstract

In recent years,  research has increasingly concentrated on fractional order systems and their approximation techniques. These systems have proven valuable for improving plant dynamics in both time and frequency domains. This paper introduces a novel approach for evaluating different approximation methods of fractional order systems and examining disturbance rejection in PID control of DC motors. The methodology involves fractionalizing an integer order derivative operator within the original integer system. The fractionalized terms are implemented using well-established approximation methods, and to identify the optimal technique, the responses of the original integer system are compared with those of the fractionalized systems. Simulation examples demonstrate that the fractionalization approach effectively identifies the most suitable method, serves as an effective comparative tool for different approximation techniques, and achieves strong disturbance rejection in PID control of DC motors. This approach is generalizable to other numerical approximation methods and applicable to broader control systems applications.