油纸复合绝缘热老化及水分影响机理的反应分子动力学模拟  

A Reactive Molecular Dynamics Simulation of Thermal Aging Process of Oil-Paper Insulation and the Influence Mechanism of Moisture

作　　者：李加才 陈继明[1] 朱明晓 宋恒高 张宏玉[2] Li Jiacai;Chen Jiming;Zhu Mingxiao;Song Henggao;Zhang Hongyu(College of Information and Control Engineering China University of Petroleum(East China),Qingdao 266580 China;College of Chemical Engineering China University of Petroleum(East China),Qingdao 266580 China)

机构地区：[1]中国石油大学(华东)信息与控制工程学院,青岛266580 [2]中国石油大学(华东)化学工程学院,青岛266580

出　　处：《电工技术学报》2020年第9期1999-2005,共7页Transactions of China Electrotechnical Society

基　　金：中央高校基本科研业务费专项资金资助项目(19CX02015A)。

摘　　要：高温和水分是导致变压器油纸绝缘劣化的主要因素,对其劣化机理进行分析具有重要意义。该文建立油纸复合绝缘的分子模型,利用反应力场(ReaxFF)模拟不同含水量下的绝缘热老化过程。统计绝缘老化过程中反应物与生成物的数量变化趋势,通过同位素标记法得到油纸复合绝缘热老化的主要反应路径和相互作用机理,重点分析水分对复合绝缘热老化过程的影响机制。结果表明:油纸复合绝缘热老化的小分子产物主要包括氢气、乙烯、甲烷、水、乙醇醛、甲酸、一氧化碳和二氧化碳。高温条件下,水分子易与纤维二糖分子形成氢键,破坏纤维二糖结构;纤维二糖裂解产生水与酸,促进绝缘油劣化。在H^+的作用下,油、纸绝缘老化相互促进,加速复合绝缘老化。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,H2 O,CH2 OHCHO,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.

关 键 词：油纸复合绝缘 水分 热老化 反应分子动力学 反应力场 

分 类 号：TM852[电气工程—高电压与绝缘技术]