Performance Analysis and Design Optimization of an Annular Winding Bilateral Linear Switch Reluctance Machine for Low Cost Linear Applications

Linear switch reluctance machine (LSRM) has been an alternative actuator for linear transportation systems such as mine hoist applications and urban ropeless elevator system. This paper proposes a novel bilateral LSRM, which stator consists of series of concrete ferrite-magnetic segments rather than laminated teeth type structures. The referred segments are magnetically isolated between each other and, thereby, eliminate the stator yoke and make much better utilization of magnetic circuit. It is found that the proposed machine features lower mass of stator core but achieves much higher thrust than a conventional teeth type LSRM. An optimization procedure is performed and is compared with results from initial design ranging from inductance characteristics, statistic force, normal force to force density and force ripple. The presented machine has gained superiority over teeth type LSRM in terms of higher propulsion force density, utilization of magnetic material, capability of fault tolerance, and low manufacturing and assembling cost.