A fractional‐order active disturbance rejection control for permanent magnet synchronous motor position servo system

Abstract

AbstractThis paper introduces a novel control scheme for the permanent magnet synchronous motor (PMSM) position servo system using a fractional‐order active disturbance rejection control (ADRC) approach. Specifically, a first‐order ADRC is employed in the current loop, while a fractional‐order ADRC is designed for the position loop. In the latter, a linear extended state observer (LESO) is utilized to estimate and compensate for disturbances, while a fractional‐order proportional derivative (FO[PD]) feedback controller is employed to enhance the control performance. Moreover, a parameter tuning method is presented based on frequency domain specifications. This technique utilizes the flat phase constraint as a design constraint to ensure that the phase is flat near the gain crossover frequency, thus ensuring that the closed‐loop system remains robust to loop gain variations. Simulation and experimental results demonstrate that the proposed fractional‐order ADRC control scheme yields improved dynamic response, disturbance rejection, and robustness to loop gain variations.