A Fuzzy-ELADRC Method for a Bearingless Induction Motor

To address the contradiction between dynamic performance and robustness of the enhanced linear active disturbance rejection control (ELADRC) method, a fuzzy-ELADRC method for a bearingless induction motor (BIM) is proposed. First, based on the air-gap flux oriented control, the first-order and second-order ELADRC are designed for the torque system and the suspension system of the BIM, respectively. Second, a fuzzy controller is introduced to adjust the controller bandwidth and observer bandwidth of ELADRC online. The fuzzy rules are established by analyzing the influence of ELADRC with different bandwidths on the BIM system, and adaptive initial bandwidth is adopted to improve the variable speed performance of the BIM. Finally, the simulation and experimental comparisons of the PID control method, the ELADRC method, and the fuzzy-ELADRC method are carried out. The results show that the proposed method not only realizes the rapid and stable suspension of the rotor, but also effectively improves the starting performance, variable speed performance, and antidisturbance performance of the BIM system.