Electric Drive for an In-wheel Fractional-slot Axial Flux Machine

摘要

This paper describes the electric drive for an in-wheel fractional-slot axial flux machine, designed for achievinga wide flux-weakening operating region.By using a slotted stator with fractional-slot windings and additional coresenclosing end windings,the axial flux machine reaches a wide constant power speed range. The machine is designed forincreasing flux-weakening capability while obtaining low harmonic back-electromotive force and low cogging torque.A 10maximize the output torque in the flux-weakening region, is designed and implemented.The goodness of both design andcontrol algorithm is proved by experimental tests.However,such a fractional-slot machine has not only advantages.Rotorlosses are very high ,and they have to be properly considered during the design process.