大型水氢氢汽轮发电机定子空心股线的优化设计

Advantages of Evaporative Cooling Technology in Large Generator-motor and Its Simulated Test

大型汽轮发电机定子线圈采用水冷的方式,由于传统空心股线采用铜质材料,损耗低,但空心导线内壁结垢、腐蚀的问题。易引起股线堵塞甚至断水并导致定子温度过高引起重大事故发生。针对此问题可采用不锈钢空心股线避免股线堵塞;不锈钢空心股线具有主绝缘耐压等级高,机械强度大、抗老化性能好等优点。本文对定子线圈采用不同股线规格、排列方式及上下层截面积等方式,以及不锈钢和铜两种材料的空心股线采用有限元方法进行发电机定子绕组损耗和温升分析研究,通过优化设计达到采用不锈钢代替铜空心股线的目的。

Stator coils of large turbo-generators are water-cooled.Traditional hollow strand is made of copper with low loss,but the inner wall of hollow strand is scaled and corroded.It is easy to cause strand blockage or even water cut-off and stator temperature is too high to cause major accidents.To solve this problem,hollow strand of stainless steel can be used to avoid strand blockage.Hollow strand of stainless steel has the advantages of high voltage withstand grade of main insulation,high mechanical strength and good aging resistance.The stator winding is analyzed by using different strand sizes,arrangement and cross-sectional area of upper and lower layers as well as hollow strand made of stainless steel and copper by finite element method.The purpose of replacing copper hollow strand with stainless steel is achieved by optimizing design.