Comparative Study of Permanent-Magnet Synchronous Machines with Different Rotor Topologies for High-Speed Applications

High-speed permanent-magnet synchronous machines (HSPMSMs) are an attractive option for proton-exchange membrane fuel-cell systems. Various HSPMSMs have been developed in the past few years. However, it is difficult to judge which the best candidate is. In this paper, aimed at driving a fuel cell vehicle air compressor, four permanent-magnet machines with different rotor topologies were designed and are compared in terms of electromagnetic, mechanical, rotor-dynamics, and thermal performance. The main topologies of these HSPMSMs are introduced and explained. Then, the electromagnetic and mechanical performance of these HSPMSMs was obtained by using a finite-element method (FEM). To reduce PM demagnetization risk, the temperature increase distributed on the HSPMSMs was also obtained. Lastly, some important conclusions were obtained.