不同长径比下真空电弧自由燃弧特性的研究
Research on the Characteristics of Free-burning Vacuum Arc Under Different Gap Distance-to-diameter Ratio
鞠思源 1贾申利 1莫永鹏 1史宗谦 1石家喜 1李毅晟1
作者信息
- 1. 电力设备电气绝缘国家重点实验室(西安交通大学),陕西省西安市 710049
- 折叠
摘要
该文研究不同触头开距(g)与直径(D)比值(g/D)条件下真空电弧的自由燃弧特性,以为进一步研究电弧控制方法提供理论支撑.实验选用直径为42mm、材料为CuCr50合金的平板触头,采用触发引弧的方式,分别观察12mm(g/D=0.286)、24mm(g/D=0.571)、36mm(g/D=0.857)触头开距,2.4至5.2kA电流峰值(Ipeak)条件下的真空电弧.结果表明:不同长径比真空电弧阴极斑点扩散速度与阴极斑点平均承载电流接近,阴极斑点扩散速度与电流峰值的平方根成正比;小长径比(g/D=0.286)真空电弧在电流峰值较大时(Ipeak＞4kA)会依次出现扩散电弧模式、点状阳极斑点模式、阳极斑点模式;大长径比(g/D=0.571、0.857)真空电弧中大量阴极斑点在初始扩散阶段结束后长期维持在阴极触头侧面,未观察到稳定的阳极斑点.结果表明:大长径比与小长径比真空电弧在形态以及阳极现象上存在较大的差异,涉及大长径比真空电弧时需要考虑电弧对于触头侧面烧蚀的问题.
Abstract
In order to provide theoretical support for further research on arc control methods,this paper mainly studies the characteristics of free-burning vacuum arc under different gap distance-to-diameter ratio(g/D).A CuCr50 plate contact with a diameter of 42mm is selected in this paper.The experiments are conducted under the conditions of gap distance of 12 mm(g/D=0.286),24 mm(g/D=0.571),36 mm(g/D=0.857)and current peak(Ipeak)from 2.4 to 5.2 kA.The results show that the cathode spot expansion speed and average carrying current are close under different g/D.Cathode spot expansion speed is proportional to the square root of the peak current.When Ipeak＞4kA,at low g/D(g/D=0.286),there are three anode modes:diffuse arc mode,foot-point mode and anode spot mode.At high g/D(g/D=0.571,0.857),numerous cathode spots remain on the side of cathode contact after the initial expansion stage,and it is difficult to form stable anode spot on the surface of anode contact.There are great differences in arc characteristics and anode phenomenon between free-burning vacuum arc under high g/D and low g/D.Serious ablative to the side of contact caused by vacuum arc under high g/D must be considered.
关键词
大长径比/自由燃弧/真空电弧特性/阴极斑点/扩散速度/平均承载电流/阳极现象Key words
high gap distance-to-diameter ratio/free-burning arc/characteristics of vacuum arc/cathode spot/expansion speed/average carrying current/anode phenomena引用本文复制引用
基金项目
南方电网公司科技项目(080037KK52200020/GZHKJXM20200086)
出版年
2024
国家科技期刊平台
NSTL
万方数据