电机是飞轮储能系统实现电能和动能转换的关键部件，为提高飞轮储能系统效率，电机转子通常在真空环境下运行。然而，在真空环境中，转子产生的热量仅能通过热辐射方式向外传递，且辐射换热强度很低。这使得转子产生的热量难以排散，导致转子温度不断升高，甚至引起磁钢退磁而损坏电机。为此，本文提出了飞轮电机定子侧低温蒸发冷却方案和转子侧高辐射涂层方案，主要探究定子侧低温和转子侧高辐射涂层对于转子温升的影响。通过实验验证所提方案对电机转子辐射换热的强化作用。实验结果表明，定子侧温度降低15℃仅使转子温升降低1℃，对于辐射换热强度的提升效果并不显著。涂覆高辐射涂层后，定子侧温度降低15℃使转子温升降低近3℃，冷却效果显著改善。将定子侧低温蒸发冷却与转子侧高辐射涂层相结合，能够进一步强化辐射换热，获得更好的冷却效果。

The motor is the key component of the flywheel energy storage system to realize the conversion of electric energy and kinetic energy. In order to improve the efficiency of the flywheel energy storage system, the motor rotor is usually operated in a vacuum environment. However, the heat generated by the rotor can only be transmitted outward through thermal radiation in a vacuum environment and the radiation heat transfer intensity is very low. This makes the heat generated by the rotor difficult to disperse, resulting in a continuous increase in the rotor temperature and even causes the demagnetization of the magnetic steel to damage the motor. Therefore, this paper proposes a low-temperature evaporative cooling scheme on the stator side of the flywheel motor and a high-radiation coating scheme on the rotor side. The effects of low temperature on the stator side and high radiation coating on the rotor side on the temperature rise of the rotor are mainly investigated. The enhancement effect of the proposed scheme on the radiation heat transfer of the motor rotor is verified by experiments. The experimental results show that only the rotor temperature is reduced by 1 °C after the stator side temperature is reduced by 15 °C. The improvement effect on the radiation heat transfer intensity is not significant. After coating the high radiation coating, the stator side temperature is reduced by 15 °C, the rotor temperature is reduced by nearly 3 °C and the cooling effect is significantly improved. The combination of low-temperature evaporative cooling on the stator side and high-radiation coating on the rotor side can further enhance the radiation heat transfer and obtain better cooling effect.

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