Static characteristics of doubly-salient brushless machines having magnets in the stator considering end-effect

This article investigates the static characteristics of both doubly-salient brushless machines having magnets in stator, namely the flux-switching permanent magnet machine (three-phase topology) and doubly-salient permanent magnet machines (including three-phase and two-phase structures), especially taking the influence of end-effect into account. The structures and operating principles are described first, and then the end-effect in the stator permanent magnet machines is investigated by a 3-D calculation, and a leakage factor reflecting end-effect is defined to modify the 2-D predicted results. The proposed approach is validated experimentally for the prototype machines.