考虑冰风耦合作用的输电导线脱冰动张力及参数影响分析  

Dynamic Tension Following Ice Shedding and Parameters’Influence Analysis of Transmission Conductor Considering the Coupling Effect of Ice and Wind

作　　者：楼文娟[1] 张跃龙 徐海巍 LOU Wenjuan;ZHANG Yuelong;XU Haiwei(Institute of Structural Engineering,Zhejiang University,Hangzhou 310058,China)

机构地区：[1]浙江大学结构工程研究所,杭州310058

出　　处：《高电压技术》2022年第3期1052-1059,共8页High Voltage Engineering

基　　金：国家自然科学基金(51838012)。

摘　　要：导线覆冰脱冰过程产生的动张力可能会导致断线及倒塔等事故发生,从而危及电力传输。导线脱冰引发的最大动张力,不仅由冰载的突然释放决定,还可能受到风的耦合影响,特别是对于大风区输电线路。为此研究了风的作用(包括水平和竖向脉动风荷载)和脱冰对导线动张力的耦合影响。通过高频天平测力风洞试验获得了不同厚度新月形覆冰导线的气动力系数。开展了某实际高压输电线路脱冰动力响应的仿真分析,研究风攻角、风速及冰厚等参数对导线脱冰最大动张力的影响。提出了考虑冰风联合作用的动张力风载放大系数μ,并分析了该系数的参数敏感性,在此基础上给出了导线脱冰最大张力的计算式,可供设计应用。研究表明:风载对导线脱冰动张力的影响很大程度上取决于风攻角,风速和冰厚;忽略风载和脱冰的耦合效应会导致导线脱冰最大动张力的低估,尤其是在70°~150°风攻角下;提出的动张力放大系数μ能够考虑风载对脱冰动张力的影响,弥补了现有规范中关于导线脱冰张力计算上的不足。The dynamic tension generated during the icing and shedding process of a conductor can easily cause accidents such as wire breakage and tower collapse,thereby endangering power transmission.The maximum dynamic tension by ice shedding of a conductor is not only determined by the sudden release of the ice load,but may also be affected by wind actions,especially for the transmission lines in the windy area.This paper investigates coupling effects of wind action(including fluctuating horizontal and vertical wind load)and ice shedding on the dynamic tension of a conductor.The high frequency force balance wind tunnel tests were carried out to obtain aerodynamic force coefficients of an ice-accreted conductor with various crescent section thicknesses.Numerical simulation was applied to the dynamic response analysis of a real high voltage transmission lines by ice shedding,and to study the influences of wind attack angle,wind speed and ice thickness on the maximum dynamic tension of conductors.By considering the combined effect of ice and wind,the wind load amplification factorμfor dynamic tension was proposed and the sensitivity of different parameters to it was analyzed.On this basis,the calculation formula of the maximum tension is given,which can be used in design applications.The study shows that ice shedding induced dynamic tension of a transmission conductor is largely dependent on wind attack angle,wind speed,and ice thickness.Regardless of coupling effects of fluctuating wind load and ice shedding,the conductor dynamic tension may be underestimated,especially under wind attack angles of 70°~150°.The amplification factorμproposed in this paper can take into account the influence of wind load on the dynamic tension by ice shedding,and make up for the lack of tension calculation in the existing specifications.

关 键 词：输电线路 覆冰导线 脉动风荷载 脱冰 动张力 

分 类 号：TM752[电气工程—电力系统及自动化]