额定电压780kV特高压交流避雷器电位分布计算与测量  

Calculation and Measurement About Potential Distribution of the U_r780kV UHV AC Metal-Oxide Surge Arrester

作　　者：王陆璐[1] 熊易[1] 汤霖[1] 左中秋[1] 陈曦[2] WANG Lulu;XIONG Yi;TANG Lin;ZUO Zhongqiu;CHEN Xi(China Electric Power Research Institute,Wuhan 430074,China;China Ship Development and Design Center,Wuhan 430064,China)

机构地区：[1]中国电力科学研究院,武汉430074 [2]中国舰船研究设计中心,武汉430064

出　　处：《电瓷避雷器》2018年第4期37-43,共7页Insulators and Surge Arresters

基　　金：中国电力科学研究院有限公司青年基金资助项目(编号:5242001700H0 SZ84-18-002)

摘　　要：适当降低避雷器额定电压可优化绝缘配合,降低特高压变电站的过电压水平或降低对设备的绝缘水平,提高工程经济性。但额定电压的降低代表避雷器内部电阻片荷电率升高,影响其电位分布均匀性。为了定量分析降低额定电压的特高压交流电站用避雷器的电位分布特性,以Y20W-780/1526型UHV MOA样机为研究对象,基于电场数值计算方法,在Ansys软件中建立3D有限元仿真模型,对5种均压电容配置方案的避雷器电位分布进行计算,选取电位分布最优的配置进行试验实测。试验采用无线测量系统,在一柱电阻片间布置36只传感器,通过测量电阻片的电流承担率反映避雷器轴向电位分布情况。对比仿真计算与试验实测结果得出两者的电位分布曲线变化趋势基本一致,最大相对偏差7.32%。考虑电阻片任意组装时电容分散性对避雷器电位分布的影响,计算出Y20W-780/1526型避雷器电位分布不均匀系数为1.129 6。验证了均压环、法兰及外套尺寸结构等条件不变的前提下,通过合理配置均压电容,可降低额定电压的特高压交流电站用避雷器满足技术规范中电位分布不均匀系数不应大于1.15的要求,研究结果可为特高压交流电站用避雷器降低额定电压设计提供参考。Decrease the rated voltage of the arrester can optimize insulation coordination,and re-duce UHV substation over-voltage level or lower insulation level of equipments,which can improve theeconomy of project. But lower rated voltage on behalf of the higher chargeability on internal resistance ofthe arrester,which will affect the MOA potential distribution. In order to study the potential distributioncharacteristics of the lower rated voltage MOA on 1 000kV substation,using the software Ansys with fi-nite element method to build 3-D model of Y20 W-780/1526 type arrester. Analysis and calculated thepotential distribution of the arrester on five different kinds of grading shunt capacitors configurationscheme,selecting the optimal configuration scheme to test. The test using wireless measurement system,which put 36 sensors between resistors in a column. The current loading rate of the resistors,whichwere measured can reacted the axial potential distribution of the arrester. The curve of potential distribu-tion shows that the simulation results and the test results are basic consistent,the maximum relative devi-ation is 7.32%.When considering the effect of resistors assembly capacitance dispersion on the arrester potential distribution,calculated the Y20 W-780/1526 type arrester potential distribution non-uniform coef-ficient is 1.129 6.This paper verified the potential distribution non-uniform coefficient of the rated volt-age decreased surge arrester which used at 1 000kV substation can match the engineering specificationrequirement,less than 1.15,by rational allocation of the grading shunt capacitors under the equalizingring,flange and coat condition such as size structure unchanged. The research results can provide refer-ence for the design of rated voltage decrease for UHV surge arresters.

关 键 词：特高压避雷器 电位分布 有限元法 降低额定电压 

分 类 号：TM862[电气工程—高电压与绝缘技术]