Design and analysis of a flux-switching permanent magnet linear machine with high thrust density

Flux-switching linear permanent magnet (FSLPM) machines with magnets and armature windings in primary mover are suitable for long stator applications such as railway and vertical transportation systems [1], thus have attracted more and more attention. Different topologies have been proposed to improve the torque /thrust density The sandwiched flux-switching machine with equal volume of permanent magnet (PM) in [2] has higher torque density than the conventional one due to the increase of slot area. On the other hand, the FSLPM machine with yokeless mover presents excellent thrust capability compared with conventional FSLPM machine, as shown in Fig. 1(a) [3]. This paper combines the ideas of sandwiched magnets and yokeless structure to propose a novel yoke-less FSLPM machine with sandwiched PMs, aiming at enhancing the thrust density, as shown in Fig. 1(b).