基于“两步浇注”的非线性电导材料涂覆方法及其性能评估  

Nonlinear Conductive Material Coating Method Based on“wo-step Casting”and Performance Evaluation

作　　者：邱宇杰 潘成 潘子君 程加明 卓然 王邸博 QIU Yujie;PAN Cheng;PAN Zijun;CHENG Jiaming;ZHUO Ran;WANG Dibo(State Key Laboratory of Power Grid Environmental Protection,School of Electrical Engineering and Automation,Wuhan University,Wuhan 430074,China;Electric Power Research Institute,China Southern Power Grid,Guangzhou 510080,China)

机构地区：[1]武汉大学电气与自动化学院电网环境保护全国重点实验室,武汉430074 [2]南方电网科学研究院有限责任公司,广州510080

出　　处：《高电压技术》2025年第3期1070-1079,共10页High Voltage Engineering

基　　金：特高压电力技术与新型电工装备基础国家工程研究中心开放基金(NERCUTNEEB-2023-KF-10)。

摘　　要：非线性电导材料表面涂覆具有优异的表面电荷抑制能力并能自适应地调控阻性电场,在直流气体绝缘开关设备(gas insulated switchgear, GIS)气-固绝缘结构设计领域广受关注,但目前通过浸渍、刷涂或者喷涂制备的涂层都存在表面光洁度低、均匀性差和重复性不好的问题,这将直接影响涂层对表面电荷的抑制效果。为此,提出了一种基于“两步浇注”的绝缘子表面涂层制备方法,基于此将非线性电导材料涂覆于锥形绝缘子表面。通过表面形貌测试、表面电荷积聚和直流沿面闪络实验将所提方法与浸渍法、刷涂法、喷涂法进行了对比。结果表明:“两步浇注”法所得涂层表面光滑均匀且无明显缺陷,表面粗糙度相比其他方法大幅下降且表面电荷抑制效果最佳。在–20 kV直流电压下,“两步浇注”涂层相比浸渍、刷涂、喷涂法可分别将正、负电荷积聚总量缩减62.7%、68.6%、77.9%与66.7%、20%、67.7%。在直流沿面闪络特性方面,“两步浇注”所得涂层的正、负极性特征沿面闪络电压相比浸渍、刷涂、喷涂法分别提升了2.7%、6.3%、20.7%与4.2%、4.7%、9.9%。进一步,结合试样表面粗糙度与表面陷阱分布的测试结果对上述实验现象进行了分析,认为不同涂覆方法下的试样表面粗糙度差异是造成表面电荷分布不同的主要原因,减小表面粗糙度会使试样的表面陷阱能级和密度也随之变小,从而加速电荷在涂层表面的消散过程。The surface coatings of nonlinear conductive materials have excellent surface charge suppression ability and can adaptively regulate the resistive electric field,which has attracted a lot of attention in the field of DC gas insulated switchgear(GIS)gas-solid insulator structure design;however,the coatings prepared by dipping,brushing or spraying have the problems of low surface finish,poor uniformity and poor reproducibility,which will directly affect the suppres-sion effect of the coating on the surface charge.In this paper,a method based on“two-step casting”is proposed for the preparation of insulator surface coatings,based on which nonlinear conductive materials are coated on the surface of con-ical insulators.The proposed method is compared with the dipping,brushing and spraying methods by means of surface morphology tests,surface charge accumulation and DC flashover experiments.The results show that coating surface ob-tained by the“two-step casting”method is smooth and uniform without obvious defects,the surface roughness is significantly decreased,and the optimum surface charge suppression effect can be achieved compared with other methods.Under-20 kV DC voltage,the coating obtained by the“two-step casting”can reduce the total amount of positive and negative charge accumulation by 62.7%,68.6%,77.9%,and 66.7%,20%,67.7%compared with the dipping,brushing,and spraying methods,respectively.In terms of DC along-surface flashover characteristics,the positive and negative po-larization characteristics along-surface flashover voltages of the coatings obtained by the two-step casting method are improved by 2.7%,6.3%,20.7%,and 4.2%,4.7%,9.9%compared with those methods.Further,this paper analyzes the above experimental phenomena by combining the test results of surface roughness and surface trap distribution,and con-cludes that the difference in surface roughness of the specimens under different coating methods is the main reason for the difference in surface charge distribution,reducing the surface roughne

关 键 词：直流 表面涂覆 “两步浇注”法 表面电荷积聚 闪络 

分 类 号：TM216[一般工业技术—材料科学与工程]