Abstract：Moisture and electric field are two of the most important factors for aging of insulation paper. For a long time, effect of moisture on the insulation paper is mostly based on macro test. Meanwhile, the numerical simulation of the electric field is based on some electrical professional software such as Ansoft, Ansys, Matlab and so on. However, these two methods can not reflect the microcosmic physical and chemical processes of the material at the molecular level. In this paper, moisture diffusions on the crystalline surface and in amorphous region of transformer insulation paper under different external electric field were dynamic simulated respectively by the material analysis software Material Studio. Results show that: The polarization effect of electric field restrains movement of water molecules on the surface of the crystal cellulose, which leads to the reduction of total diffusion coefficient D and the difference among Dx, Dy and Dz. The interaction energy between crystal cellulose surface and water molecules would be increased by electric field, which enhances the hydrophilicity of crystal cellulose surface and affects the directionality of water diffusion coefficient to some extent. Relatively, movement of water in amorphous cellulose with electric field is complicated and lack of regularity.
王有元, 杨涛, 田苗, 凡朋. 电场对绝缘纸中水分扩散特性的影响[J]. 电工技术学报, 2015, 30(1): 195-203.
Wang Youyuan, Yang Tao, Tian Miao, Fan Peng. Impact of Electric Field on the Moisture Diffusion Properties of Insulation Paper. Transactions of China Electrotechnical Society, 2015, 30(1): 195-203.
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