Abstract:Conventional bearingless permanent magnet machines usually suffer from the mechanical integrity and thermal problems since PMs are located in the rotor. In order to overcome this problem, a novel bearingless flux-switching permanent magnet(FSPM)machine(BFSPM)is proposed. Both of the windings and PMs are housed in the stator and the rotor is composed of a simple iron core with sa-lient teeth, which is suitable for some applications the rotor is disposable in medical blood pumps. The proposed BFSPM machine combines the characteristics of bearingless permanent magnet machines and FSPM machines, offering the merits of high torque and suspension force densities, low coupling between torque and suspension force and direct and convenient suspension force regulation performance. First, the machine configuration and operation principle are introduced. Then, the mathematical mo-dels of torque and radial suspension force are built. Furthermore, several leading parameters of the machine are optimized to achieve the maximum average values and the minimum ripples of torque and radial suspension force. Finally, by using the finite element method, the electromagnetic performances including the no-load EMFs of torque winding and suspension winding, torque, suspension force and the coupling between torque and suspension force are analyzed, verifying the advantages of the proposed BFSPM machine.
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