油冷式永磁同步电机流场及温度场分析

Temperature Field Analysis of Oil-Cooled Permanent Magnet Synchronous Motor for Vehicle

摘要: 由于当前对于电机高功率/扭矩密度的需求不断增加，在电机中使用直接油冷却的趋势越来越大。针对永磁同步电机在运行过程中温度过高现象，本文以一台额定功率为80 KW的车用油冷式永磁同步电机作为研究对象，分析电机各部件的损耗来源，并对电机气隙域及绕组部分进行了等效处理，通过光滑粒子流体动力学方法计算出电机各表面与冷却油的换热系数，结合有限元方法仿真模拟分析了10,000 rpm额定工况下电机内流动特性和温度分布，为电机设计提供理论依据。

Abstract: Due to the increasing demand for high power/torque density of motors, the trend of using direct oil cooling in motors is increasing. Aiming at the phenomenon that the temperature of permanent magnet synchronous motor is too high during operation, this paper takes an oil-cooled permanent magnet synchronous motor with rated power of 80 KW as the research object, analyzes the loss sources of various parts of the motor, and equivalently treats the air gap region and winding part of the motor, calculates the heat transfer coefficient between each surface of the motor and the cooling oil by using the smooth particle hydrodynamics method, and simulates and analyzes the flow characteristics and temperature distribution in the motor under the rated working condition of 10,000 rpm by combining with the finite element method, which provides a theoretical basis for motor design.