SVM-based direct thrust control of permanent magnet linear synchronous motor with reduced force ripple

This paper presents a simple space vector modulation based direct thrust control (SVM-DTC) method for position control of a permanent magnet linear synchronous motor (PMLSM). The proposed SVM-DTC method has constant switching frequency and low flux and force ripple while maintaining advantages of conventional switching-table-based DTC (ST-DTC) such as elimination of current loops, excellent dynamic response, simplicity and robustness. In the proposed method the force error value and flux error sign are used to determine the amplitude and angle of reference voltage vector. Simulation results of the proposed SVM-DTC method are presented and compared with both ST-DTC and conventional SVM-DTC methods to verify the steady state and dynamic performance of the proposed method.