配电线路典型直埋式水泥杆工频接地特性  

Power Frequency Grounding Characteristic of Typical Direct-buried Cement Rod Tower in Distribution Lines

作　　者：郑钟楠 ZHENG Zhongnan(State Grid Fujian Electric Power Research Institution,Fuzhou 350000,China)

机构地区：[1]国网福建省电力有限公司电力科学研究院,福建福州350000

出　　处：《电工技术》2021年第1期36-39,43,共5页Electric Engineering

摘　　要：直埋式水泥杆广泛应用在我国配电线路中,目前我国配网直埋式水泥杆的典型设计中未考虑工频接地阻抗的土壤适应性及故障时跨步电压、接触电压等安全性数据。为评价我国配电线路杆塔的接地安全性,通过现场实测及CDEGS软件仿真,分析了配网典型设计中水泥杆各类不同尺寸杆型故障时工频接地阻抗、地电位升、跨步电压等及影响因素。结果表明,目前各水泥杆可适应的最大土壤电阻率范围只在44~74Ω·m之间,且各类水泥杆的接触电压均超过安全限值,其接地安全性需得到关注。Buried cement rod tower is widely used in power distribution lines in our country.At present,the typical design of direct-buried cement rod in my country′s distribution network does not consider the soil adaptability of power frequency grounding impedance and safety data such as step voltage and contact voltage at fault.In order to evaluate the grounding safety of distribution line towers in China,the power frequency grounding impedance,ground potential rise,step voltage and other influencing factors of cement rod with different sizes in typical design of distribution network were analyzed by field measurement and CDEGS software simulation.The results showed that the current maximum applicable soil resistivity range of each cement pole was only between 44Ω·m and 74Ω·m,and the contact voltage of various cement rod exceeded the safety limit,and its grounding safety needed attention.

关 键 词：配电线路 接地阻抗 地电位升 跨步电压 接触电压 

分 类 号：TM85[电气工程—高电压与绝缘技术]