Sliding‐Mode Control of Electromagnetic Suspension Systems Considering Disturbance Compensation

To enhance the suspension stability of magnetic levitation systems under random disturbances, an integrated control strategy integrating a cascaded linear extended state observer (CLESO) with sliding‐mode control featuring double‐power reaching law is proposed. This approach addresses disturbance estimation and compensation both within and outside the system. First, based on the single‐point electromagnetic levitation system, a CLESO is designed using a parallel structure with dual cascading combinations. This approach reduces control system complexity, enhances disturbance estimation accuracy, and enables real‐time compensation control. Second, theoretical derivation and analysis demonstrate the effects of disturbance observation and compensation by the CLESO on system stability and error convergence regions. Based on sliding‐mode control theory, an improved double power reaching law is employed to suppress sliding‐mode output chattering, thereby enhancing the system's disturbance rejection capability. Finally, integrating the theoretical model with an experimental platform, system simulations, and experimental comparisons validates that the proposed improved sliding‐mode control strategy with the integrated CLESO possesses robust disturbance observation capabilities. It offers superior system stability and disturbance rejection, providing a valuable reference for future research in magnetic levitation control.