Analytical methods for minimizing detent force in long-stator PM linear motor including longitudinal end effects

The end effect of detent force is inherent characteristic of permanent magnet (PM) linear motors. The detent force in long-stator linear motor is caused by open longitudinal ends of PM mover, which differs from rotary motor and its short-stator counterparts. The open longitudinal ends of PM mover in long-stator linear motor cause uneven airgap magnetic flux distribution. Further, the distorted flux distributions have influence on the waveforms of detent force. So the detent force cannot be predicted accurately by conventional analytical method [1], and the utility of optimized methods need to be reconsidered for non-symmetric distributions [2].