摘要
变压器绕组材料弹性模量对其短路轴向力学性能及动稳定性有重要影响。采用动态热机械分析仪测量分析了绕组垫块弹性模量随温度的变化规律,并通过理论计算得到了铜导线弹性模量随温度的变化规律。在此基础上,以一台110kV电压等级的变压器为例,基于有限元电磁-结构耦合计算,研究了短路电流峰值时刻绕组漏磁场分布及轴向力学性能。结果表明:垫块和铜导线的弹性模量均随温度的升高而减小;在轴向短路电磁力的作用下,高、低压绕组同时受到从两端向中部的压缩作用,绕组两端的轴向位移最大,中部线饼的位移较小,应力最大值出现在中部线饼处,且高压绕组的最大位移和最大应力均小于低压绕组;突发短路时绕组的平均温度越高,其最大轴向位移越大,最大应力越小。
The elastic modulus of transformer winding material has an important influence on its axial mechanical properties and dynamic stability at short circuit. The change rule of elastic modulus of windings spacers with temperature was measured via dynamic thermal mechanical analyzer, and the change rule of elastic modulus of copper conductor with temperature was obtained by theoretical calculation. Based on finite element electromagnetism-structure coupling calculation, the leakage magnetic field distribution and axial mechanical properties of windings at the time of peak short-circuit current were calculated for an 110 kV power transformer. The results show that the elastic modulus of the spacer and copper conductor decreases with the increase of temperature. Under the effect of axial short-circuit electromagnetic force, the high and low voltage windings are subject to compression effect from both ends to the middle part. The axial displacement of the both ends is the biggest, and the displacement of the middle part is the smallest, and the maximum stress occurs at the middle part. The maximum displacement and maximum stress of the high voltage windings are smaller than those of low voltage windings. The higher the average temperature of the windings at sudden short circuit fault, the greater the maximum axial displacement, the smaller the maximum stress is.
作者
罗汉武
来文青
姜国义
林楠
崔仕伟
江翼
李梦齐
Luo Hanwu Lai Wenqing Jiang Guoyi Lin Nan Cui Shiwei Jiang Yi Li Mengqi(Maintenance Company of State Grid East Inner Mongolia Electric Power Company Ltd., Tongliao 028000, China State Grid East Inner Mongolia Grid Company Ltd., Hohhot 010000, China Wuhan NARI Limited Liability Company of State Grid Electrical Power Research Institute, Wuhan 430000, China)
出处
《绝缘材料》
CAS
北大核心
2017年第9期46-51,共6页
Insulating Materials
基金
国网蒙东科技项目(SGTYHT/14-JS-188)
关键词
温度
变压器绕组
材料
弹性模量
力学性能
temperature
transformer windings
material
elastic modulus
mechanical properties
