摘要
电力输电线路杆塔除桩基自然接地体外往往需要额外敷设人工外延接地体,实际工程中人工外延接地往往受地形、征地以及施工难度所限,提高杆塔桩基自然接地的接地散流效率具有重要意义。笔者提出基于柔性石墨复合接地材料搭建杆塔桩基立体"笼"式外敷接地装置,采用COMSOL仿真软件建立混凝土杆塔桩基散流计算模型,针对典型杆塔桩基采用"笼"式外敷接地装置的不同敷设方式、根开间距等因素进行仿真计算,验证"笼"式接地装置对杆塔散流的影响,最后针对整个杆桩基础,对比了桩基外敷接地与传统人工外延接地的散流效果。计算结果表明:随着土壤电阻率的提升,桩基"笼"式外敷接地装置的降阻效率始终保持在19%以上;与人工外延接地装置相比,外敷接地装置的散流比在90%以上,可以有效地分担桩基钢筋的散流占比;当入地电流中包含冲击高频分量时,外敷接地装置的降阻效率始终在20%以上,且外敷接地装置的散流比高于人工外延接地体。
In addition to the natural grounding of foundation, the pole and tower of power transmission line often need additional artificial grounding electrode. In practical engineering, artificial grounding is often limited by terrain, land acquisition and construction difficulty. It is of great significance to improve the efficiency of grounding divergence of natural grounding of pole and tower foundation. A three-dimensional " cage" type external grounding device based on flexible graphite composite grounding material is proposed, and a calculation model of concrete tower foundation dispersion is established by COMSOL simulation software. Different laying methods and root spacing of typical tower foundation with " cage" type external grounding device are simulated and calculated. Finally, for the whole tower foundation, the effect of foundation external grounding and traditional artificial grounding is compared. The calculation results show that with the increase of soil resistivity, the drag reduction efficiency of the cage-type external grounding device of tower foundation is always above 19%. Compared with the artificial outward grounding device, the diversion ratio of the cage-type external grounding device is above 90%, which can effectively share the diversion pressure of the reinforcement bar of foundation;When high frequency impulse component is included in the ground current, the drag reduction efficiency of cage-type external grounding device is always more than 20%, and the divergence ratio of cage-type external grounding device is higher than that of artificial epitaxy grounding electrode.
作者
高晓晶
胡元潮
姜志鹏
李光杰
周蠡
周光远
GAO Xiaojing;HU Yuanchao;JIANG Zhipeng;LI Guangjie;ZHOU Li;ZHOU Guangyuan(State Grid Hubei Power Supply Limited Company,Economic&Technology Research Institute,Wuhan 430000,China;Electrical and Electronic Engineering College,Shandong University of Technology,Zibo 255000,China;State Grid Hubei Power Supply Limited Company Ezhou Power Supply Company,Ezhou 436000,China;State Grid Hubei Power Supply Limited Company Jingmen Power Supply Company,Jingmen 448000,China)
出处
《电瓷避雷器》
CAS
北大核心
2021年第5期115-122,共8页
Insulators and Surge Arresters
基金
国家自然科学基金(编号:51807113)
山东省自然科学基金(编号:ZR2016EEQ20)
国网湖北省电力有限公司科技项目(编号:SGTYHT18JS208)。
关键词
杆塔桩基
“笼”式外敷接地装置
柔性石墨复合接地材料
接地电阻
tower foundation
"cage"type external grounding device
flexible graphite composite grounding material
grounding resistance
