Design and Optimization of Dual-Air Duct Cooling System for Rotor Permanent Magnet Flux-Switching Motor

Rotor permanent magnet flux switching (RPMFS) motors have attracted widespread attention due to high torque density. However, this type of motor will generate significant losses, leading to severe heating. Therefore, this article proposes a dual-air duct cooling system to effectively improve the cooling performance of the RPMFS motor, which fully utilizes the advantages of the rotor hole structure. First, a Clark-y airfoil axial fan is designed using the isolated airfoil and the equal circulation volume method to maximize the airflow velocity. Then, the internal air duct of the RPMFS motor is formed by opening holes in the end cap and the housing, which passes through the rotor hole. Furthermore, the response surface analysis (RSA) method is adopted to optimize the steady-state temperature of the winding, which advantage is reducing the number of the simulation. In addition, the performance of single-air duct and dual-air duct was compared, and it was found that dual-air duct can effectively reduce the steady-state temperature of the motor. Finally, a prototype motor was manufactured and tested to verify the effectiveness and feasibility of the proposed dual-air duct cooling system.