两次强对流天气对500 kV输电线路的影响  

Influence of two strong convective weather cases on a 500 kV transmission line

作　　者：康丽莉 陈科技 韩颂雨 姜瑜君 KANG Lili;CHEN Keji;HAN Songyu;JIANG Yujun(Zhejiang Institute of Meteorological Sciences,Hangzhou 310008,China;State Gird Zhejiang Economic Research Institute,Hangzhou 310008,China;Zhejiang Meteorological Information Network Center,Hangzhou 310001,China)

机构地区：[1]浙江省气象科学研究所,杭州310008 [2]国网浙江省电力有限公司经济技术研究院,杭州310008 [3]浙江省气象信息网络中心,杭州310001

出　　处：《浙江电力》2023年第3期79-87,共9页Zhejiang Electric Power

基　　金：国网浙江省电力有限公司科技项目(B311JY21000M)。

摘　　要：分析了某500 kV输电线路风偏和倒塔两次事故的气象成因,利用自动气象站的观测风速,结合基于雷达反演的三维风场,获得线路事故区域的风速分布特征:两次事故周边自动气象站观测的最大风速和极大风速偏小;雷达反演的三维风场对事故出现地点和时间均有较好的指示,导致输电线路倒塔的强对流天气与导致风偏的强对流天气相比,具有更高的回波高度、更强的上升气流,其反射率因子核心高度在6 min内下降了3.5 km以上,造成更大的地面破坏,但其局地性强,影响范围较小。分析结果表明:目前的线路设计风速在导致风偏的强对流天气下是偏安全的,但也要尽量避开可使风速放大的不利地形;对于可导致输电线路倒塔的微下击暴流,建议以“防串倒”为主要思路;在强对流天气影响下,观测风速计算的阵风系数明显大于相关规范中的取值。The meteorological causes of wind deflection and tower collapse of a 500 kV transmission lines are analyzed.The wind speed distribution characteristics in the fault area of the line are obtained by using the observed wind speed of an automatic weather station and the three-dimensional wind field based on radar inversion.The results show that the maximum wind speed and the extreme wind speed observed by automatic weather stations around the two accidents are small.The three-dimensional wind field of radar inversion better indicates the fault's location and time.Compared with strong convective weather which can cause the wind deflection,the strong convective weather which can cause the tower collapse has a higher echo height and stronger updraft.The core height of its reflectivity factor drops more than 3.5 km within 6 minutes,causing greater ground damage,but its locality is strong and the influence range is small.The results show that the current design wind speed of the transmission line is safe under the strong convective weather that causes wind deflection,but adverse terrains that can accelerate the wind speed must be avoided.It is suggested to take“cascaded collapse prevention”as the main idea for the microburst which can cause the tower collapse.In addition,under the influence of strong convective weather,the gust coefficient calculated by the observed wind speed is significantly larger than the value in the relevant specifications.

关 键 词：强对流 500 kV输电线路 三维风场 风偏 倒塔 

分 类 号：TM75[电气工程—电力系统及自动化]