Techniques for Reducing the Effects of Detent Force in PMLSMs

摘要

Detent force of permanent magnet linear synchronous motors (PMLSMs) generally causes an undesired vibration and noise. Two different reduction techniques are proposed to reduce the detent force. The technique by optimizing structure of the primary core can reduce detent force effectively, but can not remove the detent force. This method is based on the finite element method (FEM) and the Fourier analysis, and effect of adjusting the length of primary core and adopting fractional slot structure are investigated. Another technique is by improving control algorithm with a force compensator to counteract the detent force effects. The speed response experimental result shows that the peak to peak speed ripple is about only 2% by employing the proposed techniques in this paper.