Abstract Thermal load of an electric vehicle water-cooled permanent magnet synchronous motor (PMSM) with hairpin windings is evaluated using thermal-fluid-solid coupling numerical simulation method, and the thermal load at peak torque point and rated speed point is predicted. The rotor speed is defined using multiple reference frame (MRF) combining with the circumferential heat flux averaging method which could greatly shorten the time of calculation. And the simulation results are basically consistent with the test data. The simulation results show that, at peak and rated work points, the temperature difference between inlet and outlet of cooling jacket is 2.8℃ and 4.0℃ respectively. The highest temperature of stator windings and rotor magnet can meet the relevant temperature-resistant design restrict, which indicates that the coolant mass flow rate and the motor cooling jacket designation is reasonable. Different from the rated speed point, most of the heat of each component at peak torque point is used for its own temperature rising, but the heat transfer path is similar, the main path is from stator winding to insulating paper, stator core, water jacket shell and coolant. While the temperature field is stable, the heat transferred from this path accounts for more than 96% of the total heat generation.
LI Dandan,MAO Jinlong,TANG Chengkun. Numerical simulation of an electric vehicle permanent magnet synchronous motor with thermal-fluid-solid coupling method[J]. Electrical Engineering, 2024, 25(12): 42-49.
2024, Vol. 25 
