特高压输电导线风雨致振的产生机理及分析模型研究

The planned UHV transmission lines will cross over southwest regions of china，one of key technologies is that how to solve transmission line dancing problem under the condition of complex terrain, humid, rainy and icing. Recent study found that, in addition to icing dancing, under the specific conditions that rain coupled with wind can induce severely vibration, but its mechanism is not clear. This subject focus on the mechanism of rain-wind induced vibration on UHV transmission lines, studied the migration rules and form of raindrops on the cross section of the transmission lines with electric field effects, movement and oscillation of upper rain-line and down rain-line on the cross section of the transmission lines with wind load, the polarized rain-line fall off rules and turbulence characteristics of transmission lines by ionic wind. Based on the mechanism of rain-wind induced vibration on UHV transmission lines, we carried out the" long time cycle" rain-wind induced vibration lab test, modified fluid-solid- air-electric field four-dimensional mathematical model of rain-wind induced vibration, and a predictive model of rain-wind induced vibration based finite element method is proposed finally. Due to the predictive model , we analyze rainfall, oscillation angle of the rain-line, the strength of local electric field, wind load and the structures of the transmission lines impact on response of rain-wind induced vibration, clarify the key influencing parameters and rules. This paper aims to reveal the mechanism of rain-wind induced vibration on UHV transmission line, overcome the rain-wind induced vibration problem and lay the foundation for UHV transmission lines cross over region of complex terrain, humid, rainy and icing.

我国拟建特高压输电线路将跨越地形复杂、潮湿多雨且覆冰频现的西南地区,输电线路的舞动防治是关键技术之一。最新研究发现，除覆冰舞动外，降雨与风载在特定条件下耦合会诱发剧烈振动，但其产生机理尚不清楚。本课题拟围绕特高压输电导线风雨致振机理，分别就雨滴在导线微截段面的形态与运移规律及电场的影响；风载作用下导线微截段面形状及上、下雨线的运动与振荡特性；雨线极化条件下,雨滴的脱落规律和离子风对输电导线的扰流特性进行基础性研究。以机理研究为基础，进行输电导线风雨致振实验室"长周期"模拟试验，修正风雨致振液-固-气-电场四相耦合场激励数学模型，应用有限单元法建立风雨致振机理的定量预测模型。基于定量预测模型，研究了降雨量、雨线振荡角、局部电场强度、风载和导线结构等对风雨致振响应影响，理清关键影响参数及规律。本研究旨在揭示风雨致振机理，为有效控制风雨致振难题和特殊地区的特高压输电导线架设奠定理论和技术基础。

针对特高压输电线路在穿越地形复杂、潮湿多雨及覆冰频现的我国西南地区过程中可能诱发的风雨致输电导线耦合振动问题，本课题就其诱发机理进行了专题研究。研究了电场对雨线形状的影响，雨滴在导线微截段面的形态与运移规律。分析了特高压输电导线风雨致振的多种激励特性，构建了适合风雨致振条件的多耦合场数学模型。利用CFD数值方法分析了雨滴的脱落规律和离子风对输电导线的扰流特性。完成了风雨致振风洞模拟试验平台的搭建，进行了输电导线的风雨致振风洞模拟试验。结合风雨模拟试验与CFD数值方法，分别就降雨量、风载、杆塔结构、雨滴脱落、离子风风速和电场强度等对输电导线失稳振动规律的影响进行了深入分析，并建立输电导线风雨致振的定量预测模型。研究发现，输电导线在适量的降雨及特定的风速范围内会诱发大幅振动，附着雨线的极化变形及放电可进一步加剧其振动。本课题在一定程度上揭示了风雨致振机理，为有效抑制风雨致振难题和特高压输电导线在气象环境复杂地区的架设奠定理论和技术基础。