A linear hybrid switched reluctance motor with zero cogging force

Linear permanent magnet motors (LPMM) and linear switched reluctance motors (LSRMs) are suitable for translational, direct-drive position control applications. Several linear permanent magnet motors (LPMMs) have been investigated [1-3]. However, there often exists unavoidable cogging forces from LPMMs that require additional control algorithms to compensate for high-precision, position control applications [4]. In [5], the cogging force can be improved within the range of 20 N. The linear switched reluctance motor is particularly suitable for long-stroke, position control applications owing to its simple and low cost machine topology. However, there are dominant force ripples and a higher force-to-volume ratio is hard to be achieved [5].