摘要
可听噪声作为导线电晕效应的重要组成部分,是输电线路环境评估的重要指标之一。基于模拟电荷法建立了考虑弧垂影响的输电线路表面电场强度计算模型,该模型考虑了导线上电荷分布的不均匀性,基于输电线路对地电容相等的原则将分裂子导线等效成单根导线,利用保角变换并计及分裂子导线间的相互影响,最终得到了分裂子导线表面电场强度沿线分布特性,并与档距内弧垂最低点处的国际无线电干扰特别委员会推荐的导线表面最大电场强度计算结果、COMSOL Multi-physics仿真结果进行比对,验证了所提表面电场强度计算模型的准确性。其次,结合输电线路可听噪声声功率产生特性及点声源球面传播规律,将有限长导线分成若干可视为点声源的微线段,并假定该微线段上导线电荷密度相等,利用表面电场强度沿线分布可得到该微线段上的声压级,对导线沿线进行积分即可得到可听噪声3维分布情况。最后利用该模型计算了我国钟祥电磁环境长期观测站边相外20m处可听噪声大小,其计算结果与实际有效雨天统计结果的相对误差仅为1.73%,验证了所提计算模型的准确性。
Audible noise,as an important component of the corona effect of the wire,is one of the important indicators of environmental assessment of transmission lines.Based on a simulation charge method,we established a calculation model of the electric field strength of transmission lines considering the effect of sag.In this model,the non-uniformity of the charge distribution on the wire was taken into account.Firstly,using the conformal transformation and taking the mutual influence between the sub-conductors into account,we obtained the distribution characteristics of electric field strength along the surface of the sub-conductors,and compared with the COMSOL multi-physics simulation result at the lowest point of the internal sag of the span so as to verify the accuracy of the surface electric field strength calculation model mentioned.Secondly,combining the acoustic power generation characteristics of audible noise on transmission lines and the spherical propagation law of point sources,we divided the finite length wire into several micro line segments that can be regarded as point sources,assumed that the charge density of the wires on the micro line segment is equal,and utilized the surface field to get the distribution of the sound pressure level on the micro line segment.The three-dimensional distribution of audible noise can be obtained by integrating the line along the line.Finally,using this model,we calculated the audible noise at a distance of 20 m outside the Zhongxiang electromagnetic environment long-term observation station,the relative error between the calculated result and the actual effective rainy day statistical result is only 1.73%,which verifies the accuracy of the proposed calculation model.
作者
谢龚浩
付万璋
何旺龄
蓝磊
万保权
张业茂
XIE Gonghao;FU Wanzhang;HE Wangling;LAN Lei;WAN Baoquan;ZHANG Yemao(School of Electrical Engineering and Automation,Wuhan University,Wuhan430072,China;Chongqing Urban Power Supply Branch,State Grid Chongqing Electric Power Company,Chongqing400010,China;Wuhan Nari Limited Liability Company of State Grid Electric Power Research Institute,Wuhan430074,China;State Key Laboratory of Power Network Environmental Protection,China Electric Power Research Institute,Wuhan430074,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2019年第9期2990-2998,共9页
High Voltage Engineering
基金
湖北省自然科学基金青年项目(2018CFB257)
中国博士后科学基金(2018M632916)~~
关键词
模拟电荷法
电场强度
交流输电线路
可听噪声
3维分布
charge simulation method
electric field strength
AC transmission lines
audible noise
three-dimensional distribution
