过渡金属对植物油变压器的绝缘老化影响研究  

The Effect of Transition Metals on Insulation Aging of Vegetable Oil Transformers

作　　者：王宝杰 姜兴国 丛浩熹 张闯 WANG Bao-jie;JIANG Xing-guo;CONG Hao-xi;ZHANG Chuang(State Grid Gansu Electric Power Corp.,Baiyin Power Supply Company,Baiyin 730900,China;North China Electric Power University,Beijing 102206,China)

机构地区：[1]国网甘肃省电力公司白银供电公司,甘肃白银730900 [2]华北电力大学,北京102206

出　　处：《电力学报》2021年第5期454-465,共12页Journal of Electric Power

摘　　要：随着对植物油变压器的不断研究,植物油变压器的绝缘老化问题逐渐暴露出来。而过渡金属铜、铁等会在植物油变压器的绝缘老化方面产生不同程度的劣化作用,进而会导致变压器内部绝缘出现故障。因此,基于分子动力学原理,使用MaterialStudio软件从分子层面上研究了过渡金属对植物油变压器的劣化作用,并探讨了铜铁协同劣化作用的机制。从弹性模量、氢键、均方位移、剪切黏度等多个角度逐步探讨产生变压器内部绝缘性下降的微观原因。杨氏模量、体积模量、剪切模量和泊松比等力学性能参数,以及氢键、均方位移、静电能量、剪切黏度等数据表明,过渡金属会对油纸绝缘系统造成不同程度的劣化和老化,且其劣化作用与金属种类和浓度有很大关系,在不同金属浓度下,金属的劣化作用是不一样的。由所建模型的分子动力学仿真计算结果可知,6组不同金属浓度的油纸绝缘复合模型的力学性能相关参数的变化规律显示,铁原子对油纸绝缘复合模型的劣化作用大于铜原子,也大于铜、铁原子协同的劣化作用,三者之间呈现出铁>铜铁>铜的劣化作用强弱规律。纤维素的氢键、均方位移和静电能量的分析数据表明,金属含量的逐渐增加会降低绝缘纸的绝缘性,加速油纸绝缘系统的老化。其分子模拟计算结果显示,当金属质量分数为16.61%(较低浓度)时,几种混合模型对纤维素分子结构破坏作用相差不大;当金属质量分数为27.38%(较高浓度)时,油纸铜模型对纤维素分子结构的破化作用较大。从绝缘油的剪切黏度分析结果可知,其剪黏度随金属物质浓度的增加呈减小趋势,三种含金属模型对绝缘油呈现出铁>铜铁>铜的劣化强弱规律。由分子动力学模拟的结果可知,铁原子对油纸绝缘复合模型的总体劣化作用大于同等条件下的铜原子。实际应用时,由于油纸绝缘系统中铁的With the continuous research on vegetable oil transformers,the insulation aging problem of vegetable oil transformers is gradually exposed.The transition metal such as copper and iron will have different degrees of deterioration in the insulation aging of vegetable oil transformer,which will lead to internal insulation failure of transformer.Therefore,based on the principle of molecular dynamics,Material Studio software was used to study the corrosion degradation effect of transition metals on vegetable oil transformers at the molecular level,and the mechanism of copper-iron synergistic degradation was discussed.From the elastic modulus,hydrogen bond,mean square displacement,shear viscosity and other aspects,the micro reasons for the decrease of internal insulation of transformer are discussed.The Young’s modulus,bulk modulus,shear modulus,Poisson’s ratio and other mechanical property pa⁃rameters,as well as hydrogen bond,MSD(Mean Square Displacement),shear viscosity and other data show that the transition metal will cause different degrees of deterioration and aging of oil-paper insulation system,and this effect is closely related to the type and concentration of metal.Under different metal concentrations,the degradation of metal is different.According to the molecular dynamics simulation results of the model,the varia⁃tion rules of mechanical properties parameters of 6 groups of oil-paper insulation composite models with differ⁃ent metal concentrations show that,the degradation effect of iron atoms on oil-paper insulation composite model is greater than that of copper atoms,and also greater than that of copper&iron atoms.The degradation effect of iron>copper&iron>copper is form strong to weak.The analysis data of hydrogen bond,mean orientation shift and electrostatic energy of cellulose show that the gradual increase of metal content will reduce the insula⁃tion property of insulating paper and accelerate the aging of oil-paper insulating system.Its results of molecular simulation shows that,there is

关 键 词：油浸式变压器 植物油变压器 油纸绝缘 过渡金属 老化 弹性模量参数 氢键 均方位移 劣化 

分 类 号：TM214[一般工业技术—材料科学与工程]