立体接地网用于青藏铁路格拉段变电站的实例分析  

A Case Analysis in 3D Grounding Grid for Substation of Ge＇ermu to Lhasa Segment Qinghai Tibet Railway

作　　者：吕伟杰[1] 杨改蓉 王颢[3] 李晋[3] 

机构地区：[1]西南交通大学电气工程学院,四川成都610031 [2]成都纺织高等专业学校社科与基础教学部,四川成都611731 [3]铁道第一勘察设计院,甘肃兰州730000

出　　处：《电瓷避雷器》2007年第1期24-27,31,共5页Insulators and Surge Arresters

摘　　要：青藏铁路格拉段地处多年冻土地区，土壤结构较为复杂，土壤电阻率较平原地区明显偏高，传统的水平地网难以满足接地系统的要求。采用Wenner四极法测量了格拉段土壤电阻率，利用CDEGS软件进行计算得到与测量曲线吻合得较好的土壤分层结果，与实际测量值之间误差为6.8％。依据土壤分层的结果，设计立体接地网。采用数值计算方法，与水平接地网对比分析，结果表明，采用立体接地网（相对水平接地网）接触电压、跨步电压及地表电压下降了25％-50％，可以满足电站设备的安全要求。辅助采用物理降阻刺可以达到人身安全的要求。The Ge＇errmu-Lhasa section of Qinghai-Tibet railway passes through area of permanent frozen soil structure and substantial higher resistivity than that of plain. The conventional horizontal grounding grid cannot meet the system requirement. The soil resistivity of Ge＇ermu-Lhasa section was measured using Wenner tetrakis-electrodes methods, and the resistivity distribution at different soil layers was calculated using CDEGS program which showed a well coincidence with deviation 6.8% from measured value. A cubic grounding grid was worked out to meet the soil lamination value and compared with horizontal grounding grid. The result shows a reduction of contact voltage and step voltage by 25%-50% which meets the safety requirement for substation equipments as well as the personal safety requirements with introducing the physical resistance -reducing agent.

关 键 词：青藏铁路格拉段 立体接地网 土壤电阻率 

分 类 号：TM862[电气工程—高电压与绝缘技术]