Different Model-Based ADRCs Satisfying Performance Independent Control for PMSM Speed Servo System

This article presents four model-based active disturbance rejection controllers aimed at achieving the independent control in terms of servo and regulation for permanent magnet synchronous motor servo system. According to different definitions of total disturbance in system, two full-order model-based extended state observers (ESOs) and two reduced-order model-based ESOs are constructed to estimate and compensate for total disturbance. The independent control feature in terms of servo and regulation is verified, and feedback controllers are chosen and designed using frequency-domain specifications for satisfactory servo performance. Frequency-domain analyses including open loop, closed loop, disturbance rejection, noise suppression, and robustness to plant uncertainties are introduced. Comparative evaluations of disturbance rejection and noise suppression are conducted among the four controllers. Experimental results validate the effectiveness of the proposed approach in achieving independent control, robustness to plant parameters variations, and performance comparisons with other typical active disturbance rejection controller (ADRC) and PI controllers. In addition, a method for observer design is further introduced, which handles periodic disturbances on the basis of the proposed model-based ESO (MESO) framework. The experimental results validated that the proposed method effectively suppresses periodic disturbances.