摘要
工频短路电流作用下,缠绕铝包带的地线悬垂线夹系统存在发热严重问题,局部过热会造成地线发生损伤,为此针对位于悬垂线夹处地线的暂态热效应展开研究。首先根据缠绕铝包带的地线悬垂线夹系统的结构特征,利用Comsol软件构建相应的三维电磁热耦合仿真模型,计算并分析工频短路电流作用下地线悬垂线夹系统的电流密度分布与温度分布,确定发热瓶颈点的具体位置;接着讨论不同螺栓扭矩大小对地线发热瓶颈点温度的影响。研究结果表明:当工频短路电流流经缠绕铝包带的地线悬垂线夹系统时,地线与悬垂线夹船体最外侧接触点的电流密度最大,发热最为严重;温升主要集中在临近电流终端一侧的裸地线区域,同时螺栓扭矩的减小也会导致地线发热瓶颈点温度升高。
There is a serious problem of overheating in the ground wire-suspension clamp system wound by aluminium armour tape under the action of power frequency short-circuit current,and local overheating will cause damages to the ground wire.In view of the above problems,this paper studies transient thermal effect of the ground wire locating at the suspension clamp.Firstly,according to the structural characteristics of the ground wire-suspension clamp system wound by aluminium armour tape,it uses the Comsol software to build the corresponding three-dimensional electromagnetic thermal coupling simulation model,calculates and analyzes the current density distribution and temperature distribution of the ground wire-suspension clamp system under the action of power frequency short-circuit current so as to determine the specific location of the heating bottleneck.Then it discusses the effects of different bolt torques on the temperature of heating bottleneck point of the ground wire.The research results show that when the power frequency short-circuit current flows through the ground wire-suspension clamp system wound by aluminium armour tape,the current density of the outermost contact point between ground wire and overhang clamp hull is the highest and heating is the most serious.The temperature rise is mainly concentrated in the bare ground line area near the current terminal.Meanwhile,the decrease of bolt torque will lead to the increase of the temperature at the heating bottleneck point of the ground wire.
作者
郑文成
钟枚汕
郭德明
王永恒
蒋鹏程
刘刚
ZHENG Wencheng;ZHONG Meishan;GUO Deming;WANG Yongheng;JIANG Pengcheng;LIU Gang(School of Electric Power Engineering,South China University of Technology,Guangzhou,Guangdong 510641,China)
出处
《广东电力》
2020年第11期102-108,共7页
Guangdong Electric Power
基金
国家自然科学基金项目(51977083)。
关键词
架空地线
悬垂线夹
铝包带
电流密度
暂态热特性
overhead ground wire
suspension clamp
aluminium armour tape
current density
transient thermal characteristic
