不同表面改性方法对纳米SiO2改性绝缘油界面电子俘获能力的影响  

Influence of Different Surface Modification Methods on the Interface Electronic Capture Ability of Nano-SiO Modified Insulating Oil

作　　者：张静文 孙鹏 王栋 郝建[3] 唐超[1] ZHANG Jingwen;SUN Peng;WANG Dong;HAO Jian;TANG Chao(Southwest University,Beibei District,Chongqing 400715,China;State Grid Henan Electrical Power Research Institute,Zhengzhou 450000,Henan Province,China;State Key Laboratory of Power Transmission Equipment&System Security and New Technology(Chongqing University),Shapingba District,Chongqing 400030,China)

机构地区：[1]西南大学,重庆市北碚区400715 [2]国网河南省电力公司电力科学研究院,河南省郑州市450000 [3]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400030

出　　处：《中国电机工程学报》2020年第21期7114-7122,共9页Proceedings of the CSEE

基　　金：国家重点研发计划项目(2017YFB0902700,2017YBF0902702);国家自然科学基金项目(51977179);中央高校基本科研业务费专项资金资助项目(XDJK2020D018)。

摘　　要：纳米改性绝缘油具有优异的电气性能,在电力系统中的应用前景广泛,其电气性能的提升与纳米颗粒在改性绝缘油中形成的界面有关。因此,采用不同的表面改性剂制备了纳米SiO2改性绝缘油,并从微观层面探究了不同表面剂改性后的纳米SiO2与绝缘油分子间的界面性质。由实验结果可知,添加浓度为0.03 g/L的两种纳米SiO2改性绝缘油击穿电压较纯油提升效果最为明显,提升幅度分别为28.0%和17.6%,介质损耗因数均有明显增大。其中APTES表面改性后的纳米SiO2改性绝缘油的击穿电压提升效果优于HMDS。通过DFT计算得出,相较于HMDS表面修饰的纳米SiO2,APTES修饰后的纳米SiO2与烷烃的相互作用能更大,且APTES还含有较高正电势的氨基,可以捕捉更多的自由电子。因此,当界面引入电子时,APTES修饰的纳米SiO2上分布了更多的电子,说明了APTES修饰后的纳米SiO2/烷烃界面可以更多地捕获油中的自由电子,从而提升纳米SiO2改性绝缘油的击穿性能。The excellent electrical properties of nanomodified insulating oil make it have a wide application prospect. The interface properties between nanoparticles and base fluid are directly related to the electrical properties of nano-modified insulating oil. Therefore, different surface modifiers were used to prepare nano-SiO2 modified insulating oil in this paper, and the interfacial properties between nano-SiO2 and insulating oil molecules were explored from the micro level. The experimental results show that the nano-SiO2 modified insulating oil with the concentration of 0.03 g/L has a higher breakdown performance than pure oil, the increase range is 28.0% and 17.6% respectively and the dissipation factor slightly increases. The breakdown performance of nano-SiO2 insulating oil modified by APTES is better than that of HMDS. The DFT calculation shows that the interaction energy between APTES modified nano-SiO2 and alkane is larger than that of HMDS modified nano-SiO2, and APTES contains amino groups with higher positive potential, which can capture more electrons. Therefore, when electrons are introduced to the interface, more electrons distribute on the APTES modified nano-SiO2, indicating that the APTES modified nano-SiO2/alkane interface can capture more free electrons in the oil, thus improving the breakdown performance of nano-SiO2 insulating oil.

关 键 词：界面 表面改性 纳米SIO2 击穿电压 自由电子 

分 类 号：TM41[电气工程—电器]