Direct Thrust Control Approach Using Adaptive Variable Structure for Permanent Magnet Linear Synchronous Motor

Compared with field oriented control (FOC), direct thrust control (DTC) is known to provide fast and robust response for permanent magnet linear synchronous motor (PMLSM). However, classical DTC produces notable thrust ripples because parameters variation and load perturbation. A novel adaptive variable structure controller is presented. The mover flux and thrust are controlled directly by adaptive variable structure controller, and mover voltage vectors calculated by the adaptive variable structure controller are applied to the motor by means of space vector modulation. Simulation results are presented to illustrate performances of the proposed method. The system provides smooth, fast mover speed and thrust responses and is robust with respect to motor parameters variation and load perturbations.