摘要
龙卷风和下击暴流等局地强风突发性高、尺度小、风速大,是导致电力网络风偏闪络和杆塔破坏甚至倒塌的主要原因。为了揭示龙卷风作用下输电线路风灾破坏的机理,以输电线路中绝缘子的风偏位移以及端部对杆塔的空间支座反力响应为考察对象,开展了多跨输电线–绝缘子体系的风振响应规律研究。首先基于Baker-Sterling龙卷风理论模型建立了3维空间风场,考察了移动龙卷风作用下输电线路的准定常风荷载分布特征。然后采用非线性有限元数值方法,开展了输电线路龙卷风风振响应的动力时程分析。进而通过参数分析,着重考察了冲击角度、涡核半径、输电线跨数和绝缘子长度等风场和结构参数对绝缘子风偏位移和支反力响应幅值的影响规律。研究表明:绝缘子3向风偏位移及支反力响应对龙卷风的冲击角度变化敏感,其中纵向风偏位移及支反力响应随塔位的变化也显著,存在特定的最不利冲击角度及塔位;在最大风速确定的情况下,响应随涡核尺度增大而减小;各跨不平衡张力引起的纵向的位移及反力响应会随着跨数的增多而增加,随绝缘子的增长而减小;但横向及竖向风偏位移和支反力响应随跨数及绝缘子长度变化均不显著。研究为推动和完善输电线路抗龙卷风设计提供了必要的分析基础和参考依据。
Localized severe wind such as tornadoes and downbursts are responsible for structural failures and windage yaw flashover of transmission lines.They are always characterized by small size,high intensity and sudden pressure change.To investigate the mechanism of tornado-induced serious damage or collapse of multi-span transmission line-insulator system,the wind-induced vibration response of the swing displacement of insulator,as well as the spatial reaction of support on the tower,is focused on.Firstly,based on the Baker-Sterling three-dimensional analytical model for the tornado wind field,the quasi-steady wind load distribution characteristics of transmission line along the path of moving tornado is studied.Secondly,by using the nonlinear finite element numerical method,the dynamic time history analysis of tornado-induced vibration response of transmission line is conducted.Finally,by the parametric analysis,the variation of the maximum value of the responses is emphatically investigated considering different parameters,including attack angle,vortex-core radius,number of spans,and insulator length.The research indicates that the three-dimensional displacement and reaction change significantly with impact angle and location of tower,and decrease with the increase of vortex core radius.The longitudinal displacement and reaction increase and decrease significantly with the increase of number of spans and insulator length,respectively.The results provide essential databases and reference for developing tornado-resistant design of transmission lines.
作者
汪大海
韩少鸿
黄国庆
杨庆山
孙启刚
杨军永
WANG Dahai;HAN Shaohong;HUANG Guoqing;YANG Qingshan;SUN Qigang;YANG Junyong(School of Civil Engineering and Architecture,Wuhan University of Technology,Wuhan 430070,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China;Institution of Economy and Technology,State Grid Shandong Electric Power Company,Jinan 250000,China;Laiwu Branch,State Grid Shandong Electric Power Co.,Ltd.,Jinan 271100,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2022年第10期3871-3881,共11页
High Voltage Engineering
基金
国家自然科学基金(51878527,51720105005,51478373)。
关键词
龙卷风
输电线路
风振响应
动力时程分析
准定常风荷载分布
tornado
transmission line
wind-induced dynamic response
dynamic time history analysis
quasi-steady wind load distribution
