Abstract:Cellulose aging has obvious effects on its moisture absorption property. In order to evaluate the moisture content of insulation paper more effectively, this paper studies the influence of cellulose aging on the moisture diffusion in insulation paper. First, the transient moisture in the oil immersed insulation paper under different temperatures and different thickness was obtained by handing and testing experimental materials. Then, basing on the Fick’s second law and the finite element simulation model, the moisture diffusion coefficient and the equilibrium time constant of different aging oil immersed insulation paper are obtained. Finally, the effects of cellulose aging on diffusion coefficient and equilibrium time constant were studied. In the study temperature range, the diffusion coefficient has the empirical expression. The results show that with the aging of insulation paper, the rate of moisture absorption increases, and the equilibrium moisture content of insulation paper decreases at the same temperature. Besides, the equilibrium time constant decreases with aging at the same temperature.
周利军, 李会泽, 王安, 王东阳, 廖维. 纤维素老化对矿物油浸绝缘纸中水分扩散的影响[J]. 电工技术学报, 2019, 34(7): 1536-1543.
Zhou Lijun, Li Huize, Wang An, Wang Dongyang, Liao Wei. Effects of Cellulose Ageing on Moisture Diffusion in Paper Immersed with Mineral Oil. Transactions of China Electrotechnical Society, 2019, 34(7): 1536-1543.
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