灯泡贯流式水轮发电机通风系统及定子温度场

Ventilation and Stator Temperature Field of Bulb Tubular Turbine Generator

为研究电机定子温度场与通风系统流场间的耦合问题,建立了700kW灯泡贯流式水轮发电机的通风系统流场及定子温度场的三维有限元模型,依据流体力学和热传导理论,采用有限元分析方法,分析了通风系统的流场,基于通风系统压降和流体流速的分布,进而得到各表面的散热系数,结合电机定子各部分损耗热源的计算,分析了发电机的定子温度场分布,并进而考虑了定子外壳防水蚀的不同设计方案对定子温度场的影响。结果表明:在满足风机流量下的电机通风压降计算结果与实际运行时的实测数据基本吻合;定子温度在其设计的绝缘容许温度范围内,并有足够裕度,且宜选择定子支架外表面涂防蚀漆的防水蚀方案。

In order to research the coupled problem of stator temperature field and ventilation system fluid field of generator, the three dimensional finite element models of ventilation system fluid field and stator temperature field of a 700 kW bulb turbine generator are presented. According to the hydrodynamics and heat transfer theory, the fluid field of the generator ventilation system is calculated by using the finite element method. Based on the distributions of pressure and velocity of the ventilation system, the coefficients of heat transfer are obtained further. With the losses of different parts, the stator temperature field distributions are calculated. Considering different material designs of stator shell to prevent erosion, their effect on stator temperature are analyzed further. The results show that, when the flux of air flow is satisfied, the calculated ventilation pressure is coincident with the test value. The stator temperature is in the range of the permissible temperature of designed insulation and has enough tolerance. And lacquering on the shell surface is selected as the practical scheme.