Temperature rise caused by losses is a key issue for a high-speed machine. This paper deals with loss calculation and thermal analysis of a high-speed magnetically suspended PM machine (MSPMM) with an actual power of 33 kW and rotation speed of 55 332 r/min. The temperature distribution based on the finite element method is obtained by accounting for various losses, which consist of air friction losses, copper losses, and iron losses of a radial magnetic bearing, a combined radial/axial magnetic bearing, and high-speed permanent magnet machine (PMM). A back-to-back test setup with two MSPMM is fabricated for verifying the calculation results. The predicted maximum temperature of rotor is located in the center of the cylindrical permanent magnet, and the value is 143 °C. Except for the rotor, the estimated maximum temperature of the stator parts is located in tooth tips of the motor stator core, the value is 92 °C, and the error between the predicted temperature and the measured one is 9.3%. Total measured losses are 1644.4 W, the estimated total losses are 1536.7 W, the error is 6.5%, and the efficiency of the machine under test is 94.6%. The loss calculation and thermal analysis results are verified by the measured ones.

中文翻译：

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磁悬浮永磁电机的损耗计算、热分析和测量


损耗引起的温升是高速机器的关键问题。本文对实际功率为33 kW、转速为55 332 r/min的高速磁悬浮永磁电机（MSPMM）进行损耗计算和热分析。基于有限元方法的温度分布是通过考虑各种损耗而获得的，这些损耗包括径向磁力轴承、径向/轴向组合磁力轴承和高速永磁体的空气摩擦损耗、铜损耗和铁损耗机（PMM）。制作了具有两个 MSPMM 的背靠背测试装置来验证计算结果。预测转子最高温度位于圆柱形永磁体中心，值为143℃。除转子外，定子部件预计最高温度位于电机定子铁芯齿尖处，值为92℃，预测温度与实测温度误差为9.3%。测量总损耗为1644.4 W，估计总损耗为1536.7 W，误差为6.5%，被测机器效率为94.6%。损耗计算和热分析结果经实测验证。