Abstract：Cellulose aging will affect the moisture absorption capacity of insulation paper. In order to optimize the drying process of the transformer. In this paper, the influence of aging condition on the moisture diffusion in non-impregnated insulation paper was studied. Firstly, accelerated thermal aging was performed on insulation papers with different thicknesses to obtain insulation paper samples with different aging states, and then the transient moisture content in the samples of non-impregnated insulation paper at different temperatures was obtained through moisture test. The influence of cellulose aging on the transient moisture content in non-impregnated insulation paper was analyzed. Based on the finite element simulation model, the diffusion coefficient of insulation paper with different aging condition was extracted at different temperatures. Finally, the empirical formula of moisture diffusion coefficient in non-impregnated insulation paper considering aging, temperature and thickness was obtained and verified. The results show that: the aging of cellulose will reduce the moisture absorption rate of non-impregnated insulation paper, the aging of cellulose will increase the equilibrium time of moisture diffusion in non-impregnated insulation paper, in the study temperature range, considering the effect of cellulose aging, the empirical formula of the diffusion coefficient in the non-impregnated insulation paper is obtained.
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2019, Vol. 34 
