Design and Performance Investigation of Doubly Salient Slot Permanent Magnet Linear Machines

The novel doubly salient slot permanent magnet linear machines (DSSPMLMs) are proposed in this paper. First, the topology and geometric parameters of the DSSPMLMs with 12 slots are introduced, and the corresponding basic operating principle is investigated. Then, feasible slot/pole combinations and winding configurations are further analyzed. To the DSSPMLMs with 12 slots, all structures with 10/11/13/14 poles and double layer (DL)/single layer (SL) winding are optimized. Finally, the electromagnetic performance including open-circuit and static force-current characteristics are comparatively studied using 2-D finite-element analysis (FEA). The results show that the optimal slot/pole combination is 12-slots/13-poles (12s/13p) and the DL winding exhibits lower force ripple while relatively lower thrust force capability than SL winding at low electrical loadings.