Internal Model Control for a Bearingless Permanent Magnet Synchronous Motor Based on Inverse System Method

To effectively enhance the control accuracy and dynamic performance of a bearingless permanent magnet synchronous motor (BPMSM), this paper presents a novel control scheme combining the inverse system method and the internal model control. By cascading the inverse model of the BPMSM with the original BPMSM system, a decoupling pseudo-linear system is constituted. Moreover, in order to improve the robustness of the whole system and reject the influence of the unmodeled dynamics and system noise to the decoupling control accuracy, the internal model control scheme is employed for the pseudo-linear system to design extra closed-loop controllers. Consequently, the proposed decoupling control scheme incorporates the advantages of both the inverse system method and the internal model control. The effectiveness of the proposed control scheme is verified by experimental results at various operations.