Electromechanical Analysis and Experiment for a High-Speed Supported by Air Foil Bearings for Water Cooling Fuel Cells

The use of flexible foil bearings to support a high-speed Permanent Magnet Synchronous Motor (PMSM) directly driving an air compressor represents a high-power and high-speed machine. Multiple physical fields exhibit strong coupling and may even lead to conflicts with each other in the interior. Therefore, when designing PMSMs (Permanent Magnet Synchronous Motors), it is essential to comprehensively consider the limitations that these factors may impose. In this paper, a study is presented as a case example, outlining the design and optimization process of a high-speed permanent magnet motor with a 120 kW hydrogen fuel system. Firstly, we developed a prototype driven by a 22 kW motor with a rotational speed of up to 90,000 rpm. Secondly, various design aspects are discussed, particularly the rotor structure studied using the Finite Element Method (FEM) to consider electromagnetic performance, mechanical stress, and rotor dynamics. Computational Fluid Dynamics (CFD) analysis is also conducted to examine its thermal behavior. Lastly, an experimental setup was constructed to validate the machine, and the results indicate a high level of consistency between simulation and measurement values.