Thrust Ripple Compensation and Disturbance Rejection Control Method for Permanent Magnet Linear Synchronous Machines

In permanent magnet linear synchronous machines (PMLSMs), the end effect inevitably gives rise to disturbances such as the detent force. These disturbances introduce additional thrust ripples, thereby degrading the overall control precision and stability. Accordingly, this paper proposes a novel approach for thrust ripple compensation and disturbance suppression tailored to PMLSMs. First, the modeling and analysis of the machine dynamics considering various disturbances are conducted. Based on the characteristics of these disturbances, the uncertainty and disturbance estimator (UDE) is embedded within the velocity control loop to design the control strategy, enabling unified compensation and suppression of the lumped disturbances within the motor model. The proposed method significantly enhances robustness and stability while maintaining the dynamic performance of velocity tracking. Finally, the simulation results validate the effectiveness and applicability of the proposed method.