A Model-Free Predictive Current Control Method for Segmented PMLSM

The phase inductance of segmented linear motor is unbalanced, and the dynamic disturbance cannot be ignored for back electromotive force (EMF) when the mover enters and exits the stator segment. At the same time, the current and thrust control become more difficult because of the mismatch of the model parameters. To solve the above problems, this paper proposes a current control strategy based on model-free predictive current control (MFPCC). A hyperlocal model of dual three-phase permanent magnet linear synchronous motor (PMLSM) with stator segment is constructed. A predictive current controller is designed based on the deadbeat principle, and a disturbance observer is designed to compensate the effects of unbalance inductance, dynamic disturbance of back EMF and parameter mismatch. Finally, it is verified by experiments that MFPCC can effectively weaken the influence of unbalanced inductance, and suppress the disturbance of back EMF and parameter mismatch. The proposed method improves the robustness and current tracking performance, and thrust fluctuation is reduced.