Development of high power and energy efficient electric drivetrain for electromobility: Thermal Management

The aim of this work is to investigate the thermal behaviour and the cooling strategies for an Axial Flux Permanent Magnet Synchronous Motor (AFPMSM). Due to their compact design, AFPMs are suitable for applications with limited space, such as electric two-wheeler vehicles. These motors have higher power density compared to Radial Flux Permanent Magnet Motors (RFPMs), which leads to increased power output but also greater heat generation in a smaller volume. Thermal management is crucial aspect of electric motor design. Proper thermal control enhances motor efficiency and reliability, while also preventing the formation of hotspots that can damage insulation materials and accelerate the aging process. A novel embedded cooling channel design is developed. It is directly integrated into the stator of the motor, minimizing the need for additional space for cooling. Computation Fluid Dynamics (CFD) simulations are employed to estimate the thermal response of the motor. Results show that an optimized cooling channel configuration can lead to a 63% reduction in maximum winding temperature compared to the case without a cooling system. Moreover, a 22.2% reduction in copper losses is achieved, increasing the motor efficiency of 1.3%. Additionally, the cooling system allows an increase in the power density of the motor (up to +125%) without exceeding the thermal limits.