Improved predictive position control for linear synchronous motor with disturbance observer

Abstract

This paper proposes an improved predictive position control (IPPC) method based on the disturbance observer (DOB) for linear synchronous motor (LSM) to enhance the tracking accuracy and robustness against parameter mismatches and load disturbance. A soft constraint containing the difference between predictive tracking errors and their exponential convergence trajectory is developed to the cost function to improve the tracking accuracy. Moreover, the IPPC employs a variable exponential-based DOB to estimate disturbances to improve the system’s robustness to parameter mismatches and load disturbance. The control system’s stability is analyzed using the Lyapunov stability theory and Bellman’s principle of optimality. The experimental results show the effectiveness of the control scheme.