接地网置于地下车站结构顶板上方的电气安全性参数研究  

Electrical Safety Parameters of Grounding Grid Above the Roof of Underground Station Structure

作　　者：陈霞 何治新 周丹 邓树 崖尚松 王伟 王旭明 吴新刚 CHEN Xia;HE Zhixin;ZHOU Dan;DENG Shu;YA Shangsong;WANG Wei;WANG Xuming;WU Xingang(Guangzhou Metro Design and Research Institute Co.,Ltd.,Guangzhou 510000,China;Beijing Jinheyi Technology&Development Co.,Ltd.,Beijing 100160,China;Yuncheng Power Supply Company of State Grid Shanxi Electric Power Company,Yuncheng 044000,China)

机构地区：[1]广州地铁设计研究院股份有限公司,广州510000 [2]北京市金合益科技发展有限公司,北京100160 [3]国网山西省电力公司运城供电公司,山西运城044000

出　　处：《电瓷避雷器》2024年第2期128-136,共9页Insulators and Surge Arresters

基　　金：广州地铁设计研究院股份有限公司科技项目(编号:20210305001)。

摘　　要：为了研究接地网置于地下车站结构顶板上方时的各项安全性参数,以便总结接地网置于地下车站结构顶板上方这一情况的可行性和适用性条件,在CDEGS软件中建立起了接地网的仿真计算模型。首先对比接地网在车站结构底板下方和结构顶板上方的工频接地电阻值区别,其次展开了车站结构顶板上方的土壤电阻率、结构顶板上方覆土土壤厚度和接地网网格尺寸、导体直径的细化研究。结果表明车站结构顶板上方的土壤电阻率和土壤厚度对接地电阻值起重要作用,接地网的网格尺寸和导体直径对电阻值的影响甚微。最后对接地网上方地表的接触电压和跨步电压等安全性指标进行了研究,结果表明:当发生严重的短路接地故障时,在车站结构顶板上方设置接地网并不会引起地表上方的接触电压、跨步电压超标,具有较高的安全系数,证明在地下车站结构顶板上方设置人工接地网相关安全性参数是符合相关要求的。研究结论可以为该类地下车站接地网的设计和施工提供参考,有助于工程实际中在车站结构顶板上方设置接地网的设计与施工指导,具有工程实践应用指导价值。In order to study the safety parameters when the grounding grid is placed above the roof of the underground station structure,and to summarize the feasibility and applicability conditions of the grounding grid placed above the roof of the underground station structure,the simulation calculation model of the grounding grid is established in CDEGS software.Firstly,the difference between the power frequency grounding resistance of the grounding grid under the station structure bottom plate and above the structure top plate is compared.Secondly,the refinement research on the soil resistivity above the station structure top plate,the thickness of the soil covering above the structure top plate,the grid size of the grounding grid and the conductor diameter is carried out.The results show that the soil resistivity and soil thickness above the roof of the station structure play an important role in the grounding resistance,and the grid size and conductor diameter of the grounding grid have little effect on the resistance.Finally,the safety indexes such as contact voltage and step voltage on the square surface of the grounding grid are studied.The results show that when a serious short-circuit grounding fault occurs,setting the grounding grid above the top plate of the station structure will not cause the contact voltage and step voltage above the surface to exceed the standard,and has a high safety facto.It is proved that the relevant safety parameters of setting artificial grounding grid above the roof of underground station structure meet the relevant requirements.The research conclusion can provide reference for the design and construction of grounding grid of this kind of underground station,help the design and construction guidance of setting grounding grid above the roof of station structure in engineering practice,and have the guiding value of engineering practice.

关 键 词：地铁站 接地网 土壤电阻率 工频接地电阻 

分 类 号：U231.8[交通运输工程—道路与铁道工程] TM862[电气工程—高电压与绝缘技术]