Design and Analysis of a Rotor Air-Cooling Enhanced Method for Axial Flux Permanent Magnet Machine With Housing-Cooling

The temperature of axial flux motor components directly affects the performance of machine. The cooling design for the rotor is obviously difficult because of its inherent rotation characteristic. A rotor air-cooling enhanced method for axial flux machines with housing-cooling is proposed in this article. In order to improve the air-cooling performance of the rotor, tile-shaped fins are mounted to the inner wall of the housing taking into account the fluid flow characteristics of axial flux motors in a cavity. The impact of the key parameters on the thermal performance are investigated by the theoretical analysis and computational fluid dynamics. In addition, the thermal model of the tile-shaped fin is derived, and the thermal network of the rotor is constructed accordingly. Finally, two prototype motors are manufactured to evaluate the viability of the proposed approach. The results of theoretical and experimental studies show good agreement.