Permanent-magnetmotorsare widely usedin-wheel motors of electric vehiclesand hybrid vehicles. Based on a movable stator design, this paper presents a new type permanent-magnet motor, whose torque can be adjusted in order to meetdifferent driving requirements. The stator geometryis varied by means of changing movable stator positions.Accordingly, the air-gap lengthin permanent-magnet motorsis changed so that torque can be adjusted. To derive an analytical model, Fourier series expansions are employed to formulate air-gap geometry variation. The analytical modelis validated by finite element numerical results.Concerning motor torque variation capability achieved in this study, the ratio of the largest vs. the smallest torque is 2.3.
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