柔性石墨复合接地材料及其相关性能试验研究  

Study on Flexible Graphite Composite Material for Electrical Grounding and Its Correlation Experimentations

作　　者：胡元潮[1,2] 阮江军[2] 肖微[2,3] 詹清华[2,3] 黄道春[2] 王湘汉[4] 

机构地区：[1]山东理工大学电气与电子工程学院,淄博255000 [2]武汉大学电气工程学院,武汉430072 [3]佛山供电公司,佛山528000 [4]中国电力科学研究院,武汉430074

出　　处：《高电压技术》2016年第6期1879-1889,共11页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2011CB209404);中央高校基本科研业务费专项资金(2012207020204)~~

摘　　要：当前,电力系统金属接地材料在实际运行中长期面临着腐蚀、复杂地形条件下运输及施工困难、接地体与土壤贴合度不高、偷盗及人为损坏事故频发、使用降阻剂加速金属腐蚀等问题。为此,选择高纯鳞片石墨作为主要导电材料制备了具有Litz线分层结构的新型接地材料——柔性石墨复合接地材料,并对该接地材料及其连接点分别进行了电阻率与接续电阻测试、冲击电流耐受试验、力学特性试验、高/低温耐受试验以及几种典型接地网的接地试验。试验结果表明:石墨复合接地材料电阻率<10^(-5)?·m,在标准雷电流、振荡冲击电流及短路电流冲击作用下,连接点的接续电阻稳定在2 m?左右;低温(–40℃)及高温(200℃)循环试验表明石墨复合接地材料及连接点结构稳定,接地材料电阻率呈现负温度特性;抗弯、抗扭及抗拉力学性能试验表明接地体力学性能满足实际施工要求;工频、冲击模拟接地试验进一步证明提出的接地材料具备用于实际接地工程的可行性。Metallic grounding materials used in power systems nowadays face a number of certain long-standing problems, including corrosion, the difficulty in transportation and construction in complex terrain, low joint degree to soil, frequent theft and destruction, accelerated corrosion induced by resistance-reducing agents, and so on. Hence, we proposed a new type of grounding material, flexible graphite composite grounding material, which has a Litz hierarchical structure and is made of flake graphite of high purity mainly. We tested the material with various kinds of tests, including resistivity and splicing resistance measurement, high/low-temperature tolerance tests, mechanical performance tests, and electrical grounding tests in several typical grounding grids. The test results indicate that the graphite composite ground material has resistivity less than 10-（-5） ？·m, and stable resistance at contact points around 2 m？ under standard lightning current impulses, oscillation impact currents, and short-circuit current impulses. According to the high（200 ℃） and low（-40℃） temperature tolerance tests, the material and its contact point are stable, and the resistivity of the material shows a negative response to temperature variation. Bending, torsion and tensile tests prove that the mechanical performance of the grounding material satisfies application requirements. Simulative power-frequency and impulse grounding tests have further verified the feasibility of using the proposed grounding material match in practical cases.

关 键 词：柔性石墨复合接地材料 接续电阻 冲击耐受试验 高、低温耐受试验 力学特性试验 接地试验 

分 类 号：TM862[电气工程—高电压与绝缘技术]