A Reactive Molecular Dynamics Simulation of Thermal Aging Process of Oil-Paper Insulation and the Influence Mechanism of Moisture
Li Jiacai1, Chen Jiming1, Zhu Mingxiao1, Song Henggao1, Zhang Hongyu2
1. College of Information and Control Engineering China University of Petroleum (East China)Qingdao 266580 China; 2. College of Chemical Engineering China University of Petroleum (East China) Qingdao 266580 China
Abstract H High temperature and moisture are the main causes of deterioration of oil-paper insulation in transformer, which is important to analyze the degradation mechanism. Molecular models for oil-paper composite insulation were built, and thermal aging processes of insulation under different moisture contents were simulated by using reaction force field (ReaxFF). The amount of reactants and products in the aging process was monitored, and then the main reaction path of oil-paper insulation aging and interaction mechanism between oil-paper were obtained by isotope labeling method. The influence of moisture on thermal aging process of composite insulation was emphatically analyzed. The results indicate that main products of oil-paper aging are H2, C2H4, CH4, H2O, CH2OHCHO, HCOOH, CO2 and CO. Hydrogen bonds are easy to form between water and cellobiose molecules under high temperature, destroying the structure of cellobiose. Besides, water and acid molecules generated by the decomposition of cellobiose can promotes deterioration of insulating oil. Oil and paper insulation aging promote each other under the influence of H+, which can accelerate composite insulation aging.
Li Jiacai,Chen Jiming,Zhu Mingxiao等. A Reactive Molecular Dynamics Simulation of Thermal Aging Process of Oil-Paper Insulation and the Influence Mechanism of Moisture[J]. Transactions of China Electrotechnical Society, 2020, 35(9): 1999-2005.
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2020, Vol. 35 
