摘要
为了研究温度因素对季节性冻土区域接地网故障测量的影响,测量分析了冻土温度变化过程水分和盐分迁移以及电阻率情况,并在冻土参数测量结果的基础上,采用接地网无损检测装置来分析温度变化对冻土区域接地网故障测量的影响。研究结果表明,冻融阶段温度梯度和孔隙水压梯度是水分迁移的主要驱动力,冻土冻结锋面以上和锋面下缘的土壤含盐量有上升趋势,冻土土壤冻结锋面附近电阻率急剧变化,这些由温度引起的冻土变化直接影响着接地网故障测量的准确度,即冻土深度低于水平接地网深度时,测量接地网故障准确率较高。
To evaluatethe temperature effect on the fault measurement of grounding grid in seasonal permafrost area,the moisture and salt migration and resistivity in the process of permafrost temperature change are measured and analyzed.Temperature effect on fault measurement of grounding grid is analyzed by apparent magnetic impedance of electromagnetic induction measurement based on the data of frozen soil parameters.The results show that temperature gradient and pore pressure gradient are the main driving force of water migration in freezing and thawing stages.Soil salinity has escalating trend at the upper or the lower edge of freezing front in frozen soil.The resistivity changes dramatically near freezing front.These changes of frozen soil caused by temperature directly affect the accuracy of grounding grid fault measurement,that is,when the depth of frozen soil is lower than the depth of horizontal grounding grid,the accuracy of grounding grid fault measurement is higher.
作者
张晋宝
孙巍
刘春翔
周扬
曲中直
曹元成
ZHANG Jinbao;SUN Wei;LIU Chunxiang;ZHOU Yang;QU Zhongzhi;CAO Yuancheng(State Grid Heilongjiang Electric Power Co.,Ltd.,Harbin 150090,China;Electric Power Research Institute of State Grid Heilongjiang Electric Power Co.,Ltd.,Harbin 150030,China;Wuhan NARI Limited Liability Company,State Grid Electric Power Research Institute,Wuhan 43007,China;China State Key Laboratory of Advanced Electromagnetic Engineering and Technology,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《电瓷避雷器》
CAS
北大核心
2020年第4期160-166,共7页
Insulators and Surge Arresters
关键词
冻土区域
接地测量
接地故障
冻融过程
高寒
温度变化
permafrost region
grounding measurement
ground fault
freezing and thawing process
alpine region
temperature variation
