变压器绝缘油中金属钝化剂的降解产气机制研究  

Investigation on the Mechanism of Metal Passivator Degradation and Gas Generation in Oil-paper Insulation

作　　者：高思航 何雨欣 柯亭婧 李佳俊 GAO Sihang;HE Yuxin;KE Tingjing;LI Jiajun(Key Laboratory of Industrial Internet of Things&Networked Control,Ministry of Education(Chongqing University of Posts and Telecommunications),Nan’an District,Chongqing 400065,China;State Key Laboratory of Power Transmission Equipment and System Security and New Technology(Chongqing University),Shapingba District,Chongqing 400044,China;State Grid Chongqing Electric Power Company,Yuzhong District,Chongqing 400015,China)

机构地区：[1]工业物联网与网络化控制教育部重点实验室(重庆邮电大学),重庆市南岸区400065 [2]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400044 [3]国网重庆市电力公司,重庆市渝中区400015

出　　处：《中国电机工程学报》2022年第5期2012-2024,共13页Proceedings of the CSEE

基　　金：国家自然科学基金(青年科学基金项目)(51907014);重庆市自然科学基金面上项目(cstc2019jcyj-msxmX0070)。

摘　　要：相关研究表明,向油浸式电力变压器中添加金属钝化剂会导致油中溶解气体生成异常,为更好地了解油纸绝缘中苯并三氮唑类钝化剂的降解产气过程,指导绝缘油变压器故障诊断,选用在油浸式电力变压器中广泛使用的金属钝化剂——苯并三氮唑(Benzotriazole,BTA),在分子模拟环境下构建BTA分子模拟体系,基于ReaxFF反应力场对2000~3000K下BTA分子模拟体系的热解过程进行分子动力学模拟,并进一步结合BTA的热重试验分析与油纸绝缘中BTA在热场作用下的试验研究,从微观与宏观两个层面综合分析油纸绝缘中BTA的降解产气机制。仿真结果表明,BTA热解会生成小分子烃类自由基、小分子烃类化合物以及H·、N·等自由基,最终形成低分子烃类气体与H_(2)、N_(2)、NH_(3)等无机产物。宏观试验结果表明,BTA随温度的升高不断发生热解,油中BTA的加入会导致油中溶解气体生成异常,其中H_(2)、CO_(2)、CO含量明显上升,但总烃含量反而下降。结合微观分子模拟仿真分析、油中溶解气体及绝缘油相关理化参量的宏观变化规律,深入探讨了油纸绝缘中BTA在热场作用下的降解产气机制。At present,the relevant studies indicate that adding metal passivators in oil-immersed power transformer would result in the generation abnormal of dissolved gases in oil.In order to understand the degradation and gas generation prcoess of benzotriazole and its derivative passivators in oil-paper insulation and guide fault diagnosis of transformer,the benzotriazole(BTA)that widely used in the oil-paper insulation was selected as the research object,the molecular model system of BTA was established in the molecular simulation environment,and the molecular dynamics simulation was conducted to analyze the pyrolysis prcoess of BTA molecule from 2000 K to 3000 K based on reactive force field(ReaxFF).Combined with the thermogravimetric analysis of BTA and the accelerated aging experiment under thermal field condition,the mechanism of BTA degradation and gas generation in oil paper insulation was analyzed from micro and macro levels.The simulation results show that BTA can be pyrolyzed to form small molecular hydrcoarbon free radical,small molecular hydrcoarbon compound,H·and N·free radicals,which leads to the formation of low molecular hydrcoarbon gases,H_(2),N_(2)and NH_(3).The experiment results show that BTA is pyrolyzed continuously as the temperature increase,and the addition of BTA in the oil lead to the generation abnormal of dissolved gases in oil.The content of H_(2),CO and CO_(2) increase significantly,while the total hydrcoarbon content decreases.Finally,the mechanism of BTA degradation and gas generation in oil-paper insulation under thermal field condition was deeply investigated by analyzing the molecular simulation results,the generation of gas dissolved in oil and the variation trend of physical and chemical parameters of oil.

关 键 词：油中溶解气体 金属钝化剂 苯并三氮唑 分子动力学 ReaxFF力场 热重分析 产气机制 

分 类 号：TM411[电气工程—电器]