聚酰亚胺表面纳米复合层构筑及其抑制强电磁场诱发真空沿面放电机理  

Construction of Nanocomposite Layer on Polyimide Surface and Its Mechanism of Suppressing Surface Discharge in Vacuum Induced by Strong Electromagnetic Field

作　　者：杨雄 周润东[1] 杨宁 黄昆 王超[1] 李文栋[1] 宋佰鹏[1] 张冠军[1] YANG Xiong;ZHOU Rundong;YANG Ning;HUANG Kun;WANG Chao;LI Wendong;SONG Baipeng;ZHANG Guanjun(State Key Laboratory of Electrical Insulation and Power Equipment(Xi’an Jiaotong University),Xi’an 710049,Shaanxi Province,China;State Key Laboratory of Power Grid Environmental Protection(China Electric Power Research Institute),Wuhan 430074,Hubei Province,China)

机构地区：[1]电力设备电气绝缘国家重点实验室(西安交通大学),陕西省西安市710049 [2]电网环境保护国家重点实验室(中国电力科学研究院有限公司),湖北省武汉市430074

出　　处：《中国电机工程学报》2023年第12期4840-4850,共11页Proceedings of the CSEE

基　　金：国家自然科学基金项目(51827809,51707148);中国博士后科学基金项目(2021M702564)。

摘　　要：航天器运行在恶劣的空间环境中容易引发充放电现象,而叠加电磁场会导致其在较低的充电电位下发生放电,严重威胁航天器的安全运行。为揭示强电磁场诱发真空沿面放电的机理并提出抑制方法,该文采用离子交换方法对聚酰亚胺(polyimide,PI)薄膜表面进行改性处理,并基于搭建的强电磁场诱发真空沿面放电平台,结合表面陷阱、二次电子发射系数(secondary electron emission yields,SEEY)等表征手段,系统分析表面改性对抑制强电磁场诱发PI薄膜沿面放电的机理。结果表明:改性后的PI表面引入大量浅陷阱,显著降低PI薄膜的表面电阻率和SEEY,并提升了材料表面电荷的积聚与消散速率。同时,浅陷阱的引入降低了PI薄膜的SEEY和直流场下的极化能,抑制气体的解吸附与电离及二次电子倍增过程,从而显著提升了PI薄膜在抑制强电磁场诱发真空沿面放电方面的能力。该研究有望为强电磁场诱发航天器表面沿面放电的防护设计提供参考。The surface charging and discharging phenomena of spacecraft are prone to occur in severe space environment.Specifically,in the case of coupling strong electromagnetic fields,the discharge damage may occur more easily at a lower charging potential,which seriously threatens the operation of spacecraft.To reveal the mechanism and present suppression method of vacuum surface discharge induced by a strong electromagnetic field,the polyimide(PI)film surface is modified by an ion-exchange method,and a surface discharge platform in vacuum induced by a strong electromagnetic field is set up.Combined with surface trap and secondary electron emission yield(SEEY),the mechanism of surface modification to suppress the vacuum surface discharge of PI film induced by a strong electromagnetic field is systematically analyzed.The results show that numerous shallow traps introduced into the PI surface layer by surface modification account for the significantly reduced surface resistivity and SEEY of PI film.Also,the rates of the surface charge accumulation and dissipation remarkably increase.Meanwhile,the analysis shows that the introduction of shallow trap reduces the SEEY and polarization energy in a DC field of PI,and suppresses the process of gas desorption and ionization and secondary electron multiplication,resulting in the significant improvement of the performance in suppressing the surface discharge induced by a strong electromagnetic field.The research is expected to provide a reference for the protection design of surface discharge induced by strong electromagnetic fields on spacecraft.

关 键 词：沿面闪络 聚酰亚胺 强电磁场诱发放电 界面陷阱 二次电子发射 

分 类 号：TM215[一般工业技术—材料科学与工程]