In order to solve the nonlinear couplings among speed and the radial displacement of the outer rotor coreless bearingless permanent magnet synchronous motor (ORC-BPMSM), a decoupling control strategy based on the least square support vector machine (LS-SVM) generalized inverse is proposed. Firstly, the basic structure and working principle of the ORC-BPMSM are introduced, and the mathematical model of torque and suspension forces are established. Secondly, the ORC-BPMSM system is proved reversible by establishing mathematical models and reversibility analysis, then the pseudo-linear subsystems are formed by connecting the generalized inverse system, which is identified by the LS-SVM, with the original system. Furthermore, additional closed-loop controllers are designed to improve the stability and robustness of the pseudolinear subsystems. Finally, the proposed method based on LS-SVM generalized inverse is compared with traditional inverse system method by simulations and experiments. The simulation and experiment results show that the proposed control strategy has good performance of decoupling and stability.
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