500kV避雷器不同污秽状况下径向电场及电压分布的仿真研究  

Simulation of Radial Electric Field and Voltage Distribution of 500 kV MOA Under Different Pollution Conditions

作　　者：刘家豪 LIU Jiahao(State Grid Jinan Power Supply Company,Jinan 250012,China)

机构地区：[1]国网山东省电力公司济南供电公司,济南250012

出　　处：《电瓷避雷器》2021年第1期45-50,共6页Insulators and Surge Arresters

摘　　要：500 kV氧化锌避雷器一般布置于室外,其瓷套表面会受到当地环境污染以及冰霜雨雪等天气因素的影响而积污,污秽带来的瓷套表面沿面闪络问题与绝缘子表面污秽类似,不同的是避雷器内部有3节串联而成的电阻片柱,表面污秽状况对内部电阻片的电压分布以及电阻片与瓷套之间的径向电场造成的影响有待研究。应用ANSYS建立500 kV氧化锌避雷器表面污秽时的二维轴对称仿真模型,对避雷器表面瓷套清洁、均匀污秽以及出现局部干燥带时的电场分布进行了仿真计算,结果表明:均匀污秽对避雷器内部电场影响很小,而局部干燥带会在电阻片与瓷套间形成局部过高的径向电场,在参考电压作用下径向电场大小超过了电晕起始场强而导致电晕放电,加速电阻片和电介质的劣化;局部干燥带附近的电阻片承受的电压有一定程度的升高,同样会加速电阻片的老化,危害避雷器的安全稳定运行。The 500 kV MOA is generally arranged outdoors,and the surface of the porcelain sleeve will be affected by local environment pollution and weather factors such as frost,rain and snow. The surface flashover problem of the porcelain sleeve surface caused by pollution is similar to that of the insulator surface. The difference is that there are three series of resistor strings inside MOA,and the influence of surface pollution on the voltage distribution of the internal resistor and the radial electric field between the resistor and the porcelain sleeve remains to be studied. In this paper,ANSYS is used to establish a 2 D axisymmetric simulation model for the surface pollution of 500 kV MOA,and the electric field distribution when the porcelain sleeve was cleaned,evenly polluted and local drying zone was simulated. The results show that even pollution has little effect on the internal electric field of the MOA,and the local drying zone will form a locally high radial electric field between the resistor and the porcelain sleeve,The radial electric field exceeds the corona starting field strength under the reference voltage,which can cause corona discharge and accelerate the degradation of resistor and dielectric. The voltage received by the resistors near the local drying zone is increased to a certain extent,which also accelerates the aging of the resistors and jeopardizes the safe and stable operation of MOA.

关 键 词：氧化锌避雷器 污秽 ANSYS 电压分布 径向电场 

分 类 号：TM862[电气工程—高电压与绝缘技术]