高速动车组新型轻量化异步牵引电机全空间热交换机理的研究

The new type lightweight synchronous traction motor designed for high speed EMU, has a volume of 88% of that the abroad asynchronous traction motor with same power, and its power density as high as 1kW/kg. In this case, the forced cooling system becomes an important and principal problem in the design and study of this kind of motor. In this project, the heat transmission between the rotating components and the static components will be studied, also the effects caused by the inverse able heat transfer among motor ontology and rotating bearings, the correlation between the ventilation structure and cooling air distribution and heat dissipation, the influences of wind direction guide and incident angle on motor temperature rise, are will be investigated. Then, a coordinated adjust approach for the whole region three-dimensional ventilation system is proposed, which could be the foundation to ensure the thermal safety of the lightweight asynchronous traction motor. Meanwhile, the space distribution of fluid and working temperature variation inside motor with new cooling structure are will be researched, as well as their affecting mechanism on motor insulation. While working under the variable natural environment and output requests, the aging evolution of windings insulation and its impacts on motor working temperate will studied, also the inversed insulation performance attenuation that brought by the working temperature will be analyzed, and the obtained results would be helpful to enhance the early warning ability for motor temperature monitoring. Moreover, a short-term redundancy ventilation strategy with variable air volume for the traction motor cooling system is proposed, which could reduce the ventilation noise in the platform area. All the scientific investigation could provide reference for solving the practical problems encountered in the operation of the high speed EMU.

高速动车组新型轻量化异步牵引电机的体积为国外同规格异步牵引电机体积的88%，功率密度接近1kW/kg，其强迫通风系统结构的高效设计是首先需要解决的重点难题。本项目开展异步牵引电机内旋转部件与非旋转部件传热关系、电机本体与旋转轴承之间的互逆热传递影响作用、通风结构对风量分配及热量散失关联度、进风口风向导流与入射偏角对电机部件温升影响等问题研究，提出新型轻量化异步牵引电机全空间、立体式冷却通风系统的联动方案，其高效的冷却通风系统是保证轻量化异步牵引电机热安全的基础。同时开展新型冷却系统结构下流体空间分布形态及其温度的变化程度对电机绝缘的作用机理研究，探求多自然因素和运行工况综合作用下，绕组绝缘老化对温升影响的演变规律及温度反演绝缘性能衰减的变化规律，增强异步牵引电机温度监控的预警能力；此外提出牵引电机冷却系统短时变风量的冗余通风策略，降低列车在站台时产生的通风噪声，解决运行中遇到的实际问题。

随着高速动车组列车综合和智能技术的发展，对牵引用的电机在重量和性能上提出了新的技术要求，异步牵引电机的轻量化设计是技术发展的必然趋势，其强迫通风系统结构的高效设计是首先需要解决的重点难题。本项目开展了异步牵引电机内旋转部件与非旋转部件传热关系、电机本体与旋转轴承之间的互逆热传递影响作用、通风结构对风量分配及热量散失关联度、进风口风向导流与入射偏角对电机部件温升影响等问题的研究，提出了新型轻量化异步牵引电机新的冷却通风系统和轻量化综合设计方案，其高效的冷却通风系统是保证轻量化异步牵引电机热安全的基础。同时开展新型冷却系统结构下绕组绝缘老化与温度之间的影响关系，探绕组绝缘老化对温升影响的演变规律及温度反演绝缘性能衰减的变化规律。此外根据列车进出站台时停留时间，分析了牵引电机冷却系统短时变风量的通风策略对电机温升分布的影响，在保证电机发热安全的情况下，给出了降低列车进入站台时可执行的冗余通风策略，降低通风噪声，可降低列车实际运行中遇到的噪声的污染问题。本项目研制的新型轻量化异步牵引电机样机的体积为国外同规格异步牵引电机体积的90%左右，功率密度达到1.073kW/kg，达到轻量化设计的目标。