开放环境中微小电阻测量回路伴随电势特性  

haracteristic of adjoint electrodynamic potentials of micro-resistance measuring circuit in open environment

作　　者：刘辉 秦敬玉[2] 周超 贾然 张洋 孙学武 谷廷坤[4] Liu Hui;Qin Jingyu;Zhou Chao;Jia Ran;Zhang Yang;Sun Xuewu;Gu Tingkun(State Grid Shandong Electric Power Research Institute,Ji’nan 250002,China;Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials,Ministry of Education,Shandong University,Ji’nan 250061,China;State Grid Shandong Electric Power Company,Ji’nan 250001,China;School of Electrical Engineering,Shandong University,Ji’nan 250061,China)

机构地区：[1]国网山东省电力公司电力科学研究院,济南250002 [2]山东大学、材料液固态结构演变与加工教育部重点实验室,济南250061 [3]国网山东省电力公司物资公司,济南250001 [4]山东大学电气工程学院,济南250061

出　　处：《电测与仪表》2023年第4期139-143,共5页Electrical Measurement & Instrumentation

基　　金：国家自然科学基金资助项目(51731007)。

摘　　要：不同于真空密闭洁净环境,电阻测量回路的导线和样品表面在开放环境中会吸附氧化性气体、酸性气体、水分子以及灰尘等物质。研究发现,测量回路伴随电势随时间变化曲线呈现出温差电势和化学电势两种效应;化学电势绝对值随时间呈现非单调衰减。此化学电势由金属结点上两个金属界面与吸附的水分子和其它化学物质所形成。通过分析0.01Ω和0.1Ω两个标准电阻测量时,回路伴随电势随时间变化,发现测试开始阶段化学电势占据主导地位,绝对值大约是0.4μV~1.0μV,在一段时间后衰减到一个很小数值,此时回路的伴随电势以温差电势为主,绝对值大约在0.1μV~0.2μV。化学电势衰减到稳定数值的时间可能受环境湿度影响较大,典型的时间大约在2000 s~3000 s之间。研究结果对于精密电阻测量及其相关测试系统设计和测试规范指定有参考价值。Different from the clean vacuum environment,the junction of the resistance measuring circuit absorbs oxidizing gas,acid gas,water molecules,dust and other substances in the open environment.It is found that the thermoelectric and chemical electrodynamic potentials of the measuring circuit have different behaviors with the time.The absolute value of the chemical potential has a non-monotonic decay with time.The chemical electrodynamic potential is formed within two metal interfaces on the metal knots by adsorbing water molecules and other chemicals.By analyzing 0.01Ωand 0.1Ωof two standard resistance measuring circuit with potential changes over time,it is found that the chemical electrodynamic potential is dominant at the beginning of the test,and the absolute value is about 0.4μV~1.0μV,which decays to a very small value after a period of time.At this time,the adjoint electrodynamic potentials of the circuit are mainly thermoelectric potential,and the absolute value is about 0.1μV~0.2μV.The time of chemical electrodynamic potential decay to stable value may be greatly affected by environmental humidity,and the typical time is about 2000~3000 seconds.The research results are valuable for the design and specification of precision resistance measurement and the designation of test system.

关 键 词：微小电阻测试 接触电势 温差电势 表面吸附 化学电势 

分 类 号：TM934.1[电气工程—电力电子与电力传动]