Encapsulated Air Cooling System for Scalable Axial Flux Motors

A Scalable Axial Flux Motor (AxMDM) with geometrically optimized U-core laminations and a NdFeB-magnet equipped GRP disc rotor for an aviation application was developed, assembled and tested. The novel machine concept is easy to fabricate and can be scaled by the number of U-core laminations to meet different requirements for output torque and power. It shows a high torque-to-weight ratio and has an excellent utilization rate of the magnet material. In this paper, the adaption of the AxMDM concept for a propeller drive is discussed. One of the main challenges for the aviation application of electric motors is a dust robust air-cooling approach. Therefore, an encapsulated air-cooling system for the AxMDM concept was developed. The impact of the minimization of the phase elements of the motor will be introduced, followed by an investigation of the temperature behavior of the motor at variable motor speed and current injection. In the last section, the temperature behavior of the motor at nominal and maximum operating conditions will be presented.