Simulation and Experimental about the Thermal Aging Performance Improvement of Cellulose Insulation Paper
Tang Chao1, Zhang Song1, Zhang Fuzhou2, Li Xu1, Zhou Qu1,3
1. College of Engineering and Technology Southwest University Chongqing 400715 China; 2. State Grid Sichuan Electric Power Research Institute Chengdu 610072 China; 3. State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing 400044 China
Abstract：The thermal aging phenomenon of insulation paper occurs during transformer operation, and the water produced by oil-paper aging accelerates the aging of insulation paper conversely. Insulation paper aging determines the life of transformer to a large degree. Thus, research on insulation paper improvement is very significant to the safe operation of transformer. In this paper, two models were established and simulated, which are respectively the model of cellulose with water and the model of cellulose with water, Dicyandiamide, Melamine, and Polyacrylamide. The mechanical properties, diffusion coefficients of water, and glass transition temperatures of cellulose in different models were measured to study the improvement of amine on the thermal stability of cellulose. On the other hand, the modified insulation paper was developed by adding three kinds of amine into the cellulose insulation paper. Then the modified insulation paper and the non-modified paper samples were both aged under 110℃, where the DP of cellulose as well as the water content was measured regularly. The simulation results showed that, the mechanical properties of the two established cellulose models were improved. Herein, the degree of activity of water molecular in the amine modified model decreased, and the glass transition temperature of the amine modified model increased by 41K. The experiment results showed that, as the aging time increased, the DP of cellulose decreased slower and the water content in amine modified paper was less than those in the unmodified sample. The simulation and experiment both indicated that the thermal aging performance improved a certain degree by adding the amine into cellulose insulation.
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2016, Vol. 31 
