Cooling System of Outer Rotor SPMSM for a Two-Seater All-Electric Aircraft Based on Heat Pipe Technology

Due to the limitation of working situation, the driving motor for all-electric aircraft (AEA) has a higher requirement on the weight and cooling performance of motor, so the thermal problem of driving motor is more prominent. Therefore, a high-performance cooling system based on heat pipe technology is proposed. The cooling system takes full advantage of the high thermal conductivity of the heat pipe. One end of the heat pipe is inserted into the stator yoke, and the other end is outside the motor, which is connected to an aluminum radiator. First, an experimental test is built to test the cooling performance of the proposed cooling system. Second, based on 3-D transient temperature field simulation, the influences for the axial size of the radiator and thermal conductivity of heat pipe on motor temperature rise are analyzed, which is a great significance to solve the overheating problem for driving motor. Finally, a 22-pole and 24-slot outer rotor surface-mounted permanent magnet synchronous motor (SPMSM) for AEA is designed and manufactured. Temperature rise distribution of prototype under different flight conditions is tested, and the effectiveness of the proposed cooling system is verified. The power density of the driving motor is further improved.