A Hybrid-Excited Flux-Switching Machine for High-Speed DC-Alternator Applications

This paper presents a new topology of hybrid-excited flux-switching machine with excitation coils located in stator slots (or inner dc windings). After describing the three-phase structure to be investigated, the working principle is discussed, and the main electromagnetic performances are simulated by finite-element (FE) analysis. It is demonstrated that the air-gap field can be easily controlled, which is interesting for variable-speed applications. Finally, a prototype having 12 stator poles and different rotor tooth numbers (10 or 14) was built. Experiments were performed, validating the FE simulations and the operation principle. Finally, the thermal behavior of the prototype machine is investigated through experiments. It is shown that, up to 12 000 r/min, the thermal stabilization is achieved, making this topology an excellent candidate for high-speed applications.