长脉宽冲击电流下氧化锌避雷器阀片老化特性  

Aging Characteristics of Zinc Oxide Arrester Valve with Long Pulse-Width Impulse Current

作　　者：卢文浩 肖翔 韦晓星 刘婉莹 楚金伟 张宏涛 黄军翔 LU Wenhao;XIAO Xiang;WEI Xiaoxing;LIU Wanying;CHU Jinwei;ZHANG Hongtao;HUANG Junxiang(Maintenance&Test Center,CSG EHV Power Transmission Company,Guangzhou 510663,China;Xi'an XD Arrester Co.,Ltd.,Xi'an 710200,China;Xi'an Jiaotong University,Xi'an 710049,China)

机构地区：[1]南方电网超高压检修试验中心,广州510663 [2]西安西电避雷器有限责任公司,西安710200 [3]西安交通大学,西安710049

出　　处：《电瓷避雷器》2023年第4期90-95,共6页Insulators and Surge Arresters

摘　　要：在直流输电工程中,大地回线和金属回线转换是一项十分重要的操作,而转换开关两侧并联的氧化锌避雷器阀片对其过电压进行限制,确保其能转换成功。在转换开关实际工况中,氧化锌避雷器阀片承受的实际工况多数为长脉宽冲击电流。通过肖特基势垒理论以及离子迁移率对氧化锌避雷器阀片在40 ms长脉宽冲击电流下的老化规律进行研究,得出以下结论:1)长脉宽冲击电流下,U_(1 mA)先略微下降再到平缓甚至一直保持不变,即说明电流分布集中势垒较高的晶界层单元链中,并对阀片整体晶界层起到均一化作用。2)随着脉冲次数的增加,500 A残压值的增加速度由快到慢,即逐渐平缓,其中填隙锌离子的迁移建立其的电场使得后续的离子难以迁离至晶界层中,进而使得后续势垒变化速度较慢。In HVDC transmission project,the conversion of earth return line and metal return line is the key operation,and the zinc oxide arrester valve in parallel on both sides of the transfer switch limits its overvoltage to ensure successful conversion.In the actual working condition of transfer switch,ZnO arrester valve often have to withstand the long pulse width impulse current.Based on Schottky barrier theory and ion mobility,the author studies the aging law of ZnO arrester valve under 40 ms long pulse impulse current.The conclusions are as follows:1)under long pulse impulse current,U_(1 mA) decreases slightly at first,and then becomes flat or even remains unchanged,which indicates that the current distribution is concentrated in the unit chain of grain boundary layer with higher barrier,and plays a role in homogenizing the whole grain boundary layer of valve plate.2)as the number of pulses increases,the increase rate of 500 A residual voltage value gradually stabilizes,from fast to slow.The migration of interstitial zinc ions establishes its electric field,which makes it difficult for subsequent ions to migrate to the grain boundary layer,and then makes the subsequent barrier change slowly.

关 键 词：氧化锌避雷器阀片 长脉宽冲击电流 肖特基势垒 离子迁移 

分 类 号：TM862[电气工程—高电压与绝缘技术]