避雷器击穿引起的110kV主变二次跳闸事故分析  

Analysis of secondary tripping accident of 110 kV main transformer caused by lightning arrester breakdown

作　　者：黄江浩 慕宗江 林文亮 王欣浩 HUANG Jianghao;MU Zongjiang;LIN Wenliang;WANG Xinhao(Zhangjiakou Power Supply Company of State Grid Jibei Power Co.,Ltd.,Zhangjiakou 075000,China)

机构地区：[1]国网冀北电力有限公司张家口供电公司,河北张家口075000

出　　处：《黑龙江电力》2022年第4期350-354,共5页Heilongjiang Electric Power

摘　　要：以110 k V某变电站事故跳闸为案例,通过故障录波器快速查找、分析变压器差动保护二次跳闸的实际动作过程,确定事故原因为35 k V线路侧本身存在单相接地、室外一次设备避雷器因受潮而绝缘性降低被击穿,从而造成两相接地短路引起主变第一次跳闸;随后由于风力作用导致被击穿的A相避雷器刮到B相,形成相间短路,造成主变差动再次跳闸。鉴于此次案例分析,提出了有针对性的解决措施及预防建议。Taking the accident trip of a 110 kV substation as an example,through the fault recorder to quickly find and analyze the actual action process of the secondary trip of transformer differential protection.It is determined that the cause of the accident is that there is single-phase grounding on the 35 k V line side,the insulation of outdoor primary equipment arrester is reduced and broken down due to moisture,resulting in two-phase grounding short circuit and the first trip of main transformer;Then,due to the action of wind,the broken down phase A arrester scraped to phase B,forming a phase to phase short circuit,causing the differential of the main transformer to trip again.In view of this case analysis,this paper puts forward targeted solutions and prevention suggestions.

关 键 词：差动保护 避雷器 两相接地 相间短路 

分 类 号：TM862[电气工程—高电压与绝缘技术]