高电压下多孔材料沿面闪络特性综合实验  

Comprehensive experiments on the surface flashover characteristics of porous materials under high voltage

作　　者：朱明晓[1] 李孟陶 孟庆伟[1] 李鹏[1] 董磊[1] 陈继明[1] ZHU Mingxiao;LI Mengtao;MENG Qingwei;LI Peng;DONG Lei;CHEN Jiming(College of New Energy,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中国石油大学(华东)新能源学院,山东青岛266580

出　　处：《实验技术与管理》2024年第10期85-92,共8页Experimental Technology and Management

基　　金：山东省自然科学基金项目(ZR2021ME027);中国石油大学(华东)教学改革项目(YJG2022040,CM2022056,QN2022019)。

摘　　要：针对电气设备复合绝缘在高电压下极易发生沿面闪络故障问题,提出利用多孔结构提升闪络强度的方法,并设计了多孔绝缘材料沿面闪络特性综合实验。利用油/水乳液法制备了多孔聚二甲基硅氧烷材料,通过观测微观形貌分析了材料的孔隙分布特性,实验测试了直流和交流电压下的沿面闪络强度,通过等温表面电位衰减、表面电荷扫描和闪络路径观测探讨了闪络强度提升机理,利用表面流注发展的流体仿真考察了孔隙对沿面放电的影响,揭示了多孔结构的抑制碰撞电离和促进表面电荷消散效应在提升闪络强度中的作用。该实验涉及电气、材料、物理及多物理场模拟,可有效提高学生的实验、仿真及理论分析等方面能力。[Objective]Gas–solid composite dielectrics are important electrical insulation materials widely used in civil and military high-tech fields,such as electrical/electronic engineering,aerospace,and strong electromagnetic pulse.However,composite insulation is prone to flashover under high electric fields,thus improving the surface flashover strength,which is a key issue in enhancing the overall performance of power equipment.The surface morphology of solid dielectrics has a significant impact on the flashover strength.However,existing surface microstructure tailoring methods are based on the etching approach,which can only construct surface holes or groove-like structures,and the morphology resolution is limited to the micrometer scale.In contrast to etching methods,which only change the surface morphology,this study constructs a three-dimensional foam-like porous structure to effectively enhance the surface flashover voltage.[Methods]Polydimethylsiloxane(PDMS)was selected as the matrix material to prepare bulk porous materials via the oil/water emulsion method.Deionized water was dispersed into PDMS by electrical stirring,and the PDMS and water droplets formed the oil/water emulsion.Afterward,PDMS was cross-linked and solidified by heating to form a porous structure with high mechanical strength.Three different mass ratios of deionized water to PDMS,namely 10%,30%,and 50%,were considered in the experiments.A comprehensive experimental system was established to characterize the surface flashover characteristics of porous insulation materials under high voltage.The flashover strength in different gas atmospheres was tested in a closed gas discharge experimental chamber,and the initiation and development processes of surface discharge were analyzed through optoelectronic joint diagnosis.The isothermal surface potential decay method was employed to measure the trap energy distribution and explore the influence of porous structure on charge dissipation rate and trap distribution.A fluid simulation model for surface st

关 键 词：复合绝缘 沿面闪络 多孔结构 综合实验 提升机理 

分 类 号：TM215.92[一般工业技术—材料科学与工程]