大型汽轮发电机定子变结构对温度场的影响

Research on the Effects of the Temperature Field of Variable Structure for a Large Air-cooled Turbo Generator Stator

汽轮发电机通风冷却技术对汽轮发电机的容量和性能有决定性的影响.针对大容量汽轮发电机通风冷却要求高的问题,以某大型空冷汽轮发电机定子为例,依据CFD原理,提出了两种改变结构的方案,保持铁芯的总有效长度不变,改变铁芯叠片的厚度不改变风沟数量和改变风沟的数量.模拟不同结构定子内部的流场和温度场,分析原结构和变化后结构的流场和温度场,以及电机各部分温度的空间分布特性,比较定子在不同结构下的运行性能.合理布置电机的通风结构,提高传热介质的利用率,降低铁芯与绕组等的温升.研究结果表明变结构后模拟最大温升为118℃,比原结构模拟结果的温升有所降低,且流场温度场分布更均匀,为大型空冷汽轮发电机定子的结构设计提供理论依据.

Capacity and performance of turbo generator are definitively affected by ventilation and cooling tech- nique of turbo generator. With the development the large capacity of turbo generator, higher requirements on venti- lation and cooling technology are put forward. In a large air-cooled turbine generator stator, according to the princi- ple of CFD, the flow field and temperature field inside the stator of different structure are simulated. Two designs a- bout stator are proposed. Flow field and temperature field of the original and variational structure and the spatial distribution characteristics of each part of the motor are analyzed, and the performance of the stator under different structures is compared. Decorating the ventilation structure reasonably, the utilization rate of heat transfer medium can be made, the temperature rise of iron core and winding is reduced. Safe and efficient operation is guaranteed for the motor. After variable structure the maximum temperature of 118~C, compared to the original structure of the simulation results the temperature is lower, the flow field and temperature field distribution is more homogeneous. The results of the study will provide theoretical references for design of ventilation cooling of large air-cooled turbo generator stator.