Self-Excited Wound Field Flux Modulated Machine using fractional-slot concentrated winding

This paper proposes a self-excited wound field flux modulated machine, where the magnetic flux variation in a differential frequency between the armature working rotating magnetic field frequency and the rotor rotation speed frequency is effectively utilized for the rotor field excitation. And a diode rectifier circuit on the rotor achieves the AC/DC conversion between the rotor harmonic winding and rotor field winding. In this paper, this new technique is applied during the design and analysis of wound field flux modulated machine with 12-teeth/l0- poles fractional-slot concentrated winding. Owing to its special winding structure, the stator of the proposed machine can generate sub-harmonic magnetic motive force (MMF) to excite harmonic winding in the rotor. Compared to the existed sub-harmonic excitation machine, the proposed machine can generate the sub-harmonic MMF without any extra equipment or winding.