Precision motion control of permanent magnet linear synchronous motor servo system based on an integrated controller with inertia variation compensation

Abstract

To achieve high robustness and precise motion control of permanent magnet linear synchronous motor servo system, an integrated controller is presented, including a velocity feed forward controller, a zero phase error tracking controller, a disturbance observer and inertia variation compensator. The velocity feed forward controller and the zero phase error tracking controller are included to improve tracking performance and the disturbance observer is involved to enhance disturbance rejection. However, both the zero phase error tracking controller and the disturbance observer are sensitive to inertia variation which often occurs in servo systems. So, an inertia compensator, which consists of a perfect tracking controller for the current loop and a compensation gain, is proposed to retain tracking performance. Detailed experiments are conducted on a PMLSM servo system to confirm the effectiveness of the integrated controller.