New Design of the Claw-pole Transverse Flux Permanent Magnet Machine

This work present a new configuration of clawpole transverse flux permanent magnet synchronous machine (TFPM) with a discoid rotor and with a stator which contains teeth in the form of claws allowing conduction of the flux in the axial direction into the stator which is formed by an inner cylindrical part and an outer cylindrical part. The machine with an axial air gap gives the advantage of; the possibility to have a machine with less magnet volume and to operate with a same rotor disc for two stator phases, in contrast to the existing claw pole machines. The machine combines the advantages of Synchronous Transverse flux Machines (TFPM) and those of the Axial Flux Synchronous Machine (AFPM). Compared to AFPMs, the claw-pole TFPM machine with discoid rotor and axial air gap has the advantages of a high electric and magnetic loading which leads to a very high torque density of the TFPM, and using an inserted winding between the stator inner and outer parts, instead of distributed or fractional-slot ones, this discards the end-windings of the AFPMs which minimize the copper losses. This design require a specific sizing of the stator teethes where the dimensions depend of the used length of the overlap between teethes. This configuration presents a less voluminous machine and can be mounted directly in vehicle wheels or for the applications where machine with smaller length in the axial direction is needed.