大型蒸发冷却汽轮发电机定子绕组温度计算

在介绍了利用汽化潜热进行热交换实现电机定子绕组蒸发冷却的工作原理基础上,说明了电机定子铁心采用全浸式与绕组强迫内冷结合的新型蒸发冷却技术,不仅其绕组温升低,而且冷却介质单一,可以为电机的运行提供安全、可靠和高效的绝缘环境及冷却效果.并以300MW汽轮发电机设计数据为依据,根据空心股线内部介质两相流动特性,对空心股线内介质两相流动阻力、蒸发点位置等参数进行计算,分析了定子绕组温度沿轴向温度分布情况以及负荷变化对温度的影响,将试验值进行对比分析,验证了蒸发冷却技术在汽轮发电机上应用的可行性,同时为进一步应用于大型发电机提供理论依据.

Calculation of temperature distribution in the stator of larger evaporative cooling turbo-generator

Evaporative cooling for turbin generator is an independent innovative technology developed in China.In this paper,the theory of evaporative cooling for the generator stator is explained,and the advantage of applying immersion and forced inner cooling type of evaporative cooling are fully discussed.The new technology featuring low temperature increasing and only one type of cooling medium is much safer,reliable and efficient.Moreover,according to the 300MW turbo-generator design specification,and based on the two phase fluxion of cooling medium in the hollow conductor,the calculation of the medium fluxion resistance and the evaporative point of the cooling medium in the hollow conductor are proposed.Analysis of the temperature distribution along the stator winding is carried out and calculation is compared with the experiment results to demonstrate the feasibility of the proposed calculation.