采煤机用牵引电机发热与传热耦合研究

Coupling research on heating and heat transfer of traction motor for coal mining machine

采煤机用牵引防爆型水冷电机受安装空间限制,功率密度大、电磁负荷高,发热严重,针对其特殊结构及换热机理,建立了发热和传热耦合模型,给出了水套内外的对流换热系数的确定方法,采用有限体积法对电机的定转子及冷却水套的温度场进行了计算分析。计算结果与试验数据对比证明所建耦合模型可真实模拟电机实际传热机理。结果表明电机转子近似为等温体,气隙的热阻使得其温度远高于定子。而电机定子温度最高处位于上层绕组靠近槽楔处。调整冷却水的流速和水套结构对电机的温度分布有较大影响,适当的水速和水套结构,可达到最小代价获得最佳冷却效果。研究结果可作为采煤机牵引电机热控制及优化设计的理论基础。

Traction explosion-proof type water-cooled motor with big power densities and serious heat emission because of space restrictions is used for the coal mining machine. Heating and heat transfer coupling model was established in this paper, according to its special structure and heat transfer mechanism. Determination method of convection coefficient of heat transfer inside and outside the water jacket was giv- en. The temperature field in motor stator, rotor and cooling water jacket was calculated and analyzed with finite volume method. Practical motor heat transfer mechanism can be simulated by this coupling model which was proved by the comparison between calculation results and experimental data. The motor rotor showed by the results is approximatively isothermal body and its temperature is far higher than stator be- cause of the gap thermal resistance. The upper winding which is near slot wedge is the highest tempera- ture point in motor stator. Great influence on the motor temperature distribution will be gained when the flow velocity of the cooling water and the structure of water jacket are adjusted. The lowest cost and best cooling effect can be achieved by the proper water velocity and water jacket structure. The results can be used as the basal theory for coal winning machine traction motor heat control and optimization design.