Model-Free Control of Permanent Magnet Synchronous Linear Motor Based on Ultra-local Model

A model-free control (MFC) method is proposed to improve the dynamic response performance of permanent magnet synchronous linear motors (PMSLMs) and reduce motor parameter changes during motor operation. The MFC is established based on an ultra-local model that uses only the input and output of the system without using any PMSLM parameters. Compared with the conventional proportional-integral (PI) control method, the robustness of the MFC system is superior and can counteract the effects of changing motor parameters and external disturbances. Simulations and experiments are conducted with steady-state operation, sudden addition and subtraction of loads, and motor parameter perturbations. The results confirm that the proposed method is useful and robust to uncertainties in motor parameters and helps improve the dynamic performance of the PMSLM.