Conventional 1-phase permanent magnet (PM) brushless dc motors usually employ an asymmetric airgap in order to produce a starting torque [1]. However, due to their relatively low starting torque and uni-directional rotation, generally, they are only used in applications such as fans and pumps. An alternative topology of 1-phase PM brushless dc motor is the flux-switching permanent magnet (FSPM) machine, which was originally proposed in [2] and which has a simple and robust salient-pole rotor, the permanent magnets being located on the stator together with the single-phase winding. Recently, the electromagnetic performance of an 8/4, i.e. 8 stator-slots/4 rotor-poles, FSPM motor was investigated [3]. It employed an asymmetric laminated rotor, similar to that which is used in single-phase switched reluctance machines, to provide the starting torque. However, the starting torque which results when the rotor is at a stable rest position, under the influence of saliency torque, was not addressed in detail and the influence of design parameters on the electromagnetic torque was not investigated.
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