The thermal management system has significant impacts on the efficiency of propulsion electric machines in the more electric aircraft. This article proposes a predictive thermal management system by utilizing the thermal-magnetic coupling phenomenon to improve efficiency. There are three major innovated contributions. First, the theoretical mathematic model of the temperature and the electromagnetic energy conversion efficiency is studied, which provides analytical expressions to describe power loss at different motor operation statuses. Second, based on the model, a predictive thermal management system is proposed to actively adjust the cooling according to the efficiency at real-time temperature, maintaining an optimal high-efficiency status. Third, the energy consumption of the cooling system, such as the pump, is also optimized to improve the overall efficiency. Meanwhile, the cooling system is designed to prevent any excessive temperature rise to ensure thermal safety and insulation lifetime. A partial stator prototype is implemented and tested in a thermal chamber. Experiments show that the motor loss is reduced by up to 7%, the cooling system working time is reduced by 30%, and the total system loss is reduced by up to 9%, which validates the proposed predictive thermal management system.

中文翻译：

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多电动飞机中高速推进电机预测热管理的创新方法

热管理系统对电动飞机中推进电机的效率有显着影响。本文提出了一种利用热磁耦合现象来提高效率的预测热管理系统。创新贡献主要有三点。首先，研究了温度和电磁能量转换效率的理论数学模型，为描述电机不同运行状态下的功率损耗提供了解析表达式。其次，基于该模型，提出了一种预测热管理系统，根据实时温度下的效率主动调整冷却，保持最佳的高效状态。三、冷却系统的能耗，如泵、还进行了优化以提高整体效率。同时，冷却系统旨在防止任何过度温升，以确保热安全和绝缘寿命。部分定子原型在热室中实施和测试。实验表明，电机损耗减少高达 7%，冷却系统工作时间减少 30%，系统总损耗减少高达 9%，验证了所提出的预测热管理系统。