长空气间隙负极性操作冲击放电特性研究(Ⅱ)-间隙系数  

Research on Typical Long Air Gaps With Negative Switching Impulses(Ⅱ)-Gap Factor

作　　者：安韵竹[1] 戴敏[2] 李志军[2] 蓝磊[1] 文习山[1] 王羽[1] 叶奇明[2] 

机构地区：[1]武汉大学电气工程学院,湖北省武汉市430072 [2]中国电力科学研究院,湖北省武汉市430074

出　　处：《中国电机工程学报》2014年第24期4145-4151,共7页Proceedings of the CSEE

摘　　要：大气环境、电极布置方式和间隙类型等对长空气间隙的负极性操作冲击放电特性均有不同程度的影响。分别采用20/2 500μs和80/2 500μs两种负极性操作冲击电压波进行放电试验,研究了气象条件、波头时间、下电极高度及导线接地方式等对空气间隙放电特性的影响,并对以棒–板间隙为基准,分析计算棒–棒间隙、棒–线间隙的间隙系数。试验结果显示:湿度对长空气间隙的负极性操作冲击放电特性试验具有明显的影响;间隙距离大于3 m时,20/2 500μs负极性操作冲击电压波作用下空气间隙的50%放电电压较高,间隙距离小于3 m时,80/2 500μs负极性操作冲击电压波作用下空气间隙的50%放电电压较高;下电极高度对棒–棒间隙放电特性具有一定的影响;导线接地方式对棒–线间隙的50%负极性操作冲击放电电压具有显著影响。间隙系数随间隙距离呈非线性变化趋势,棒–线间隙对棒–棒间隙的间隙系数随间隙距离增大基本趋于稳定值1.05。The negative discharge characteristics of long air gaps vary with atmospheric environment, tests＇ setup and gap type. Two waveforms of -20/2 500 μs and -80/2 500 μs were employed in present tests to study the factors influencing the negative switching discharge characteristics of long air gaps, such as atmosphericcondition, applied voltage waveform, grounded rod height and conductor grounded method, The gap factors of rod-rod gaps and rod-conductor gaps were calculated based on the rod-plane gaps. The tests results indicated that the air humidity and conductor grounded method had significant influences on negative discharge characteristics of long air gaps; the 50% discharge voltage of these typical air gaps were higher with applied voltage of -20/2 500 μs than that with applied voltage of-80/2 500 μs when the gap distance exceeded 4m and versus when the gap distance was smaller than 3 m. Grounded rod height had some effects on 50% discharge voltage of these typical air gaps. Gap factors increased nonlinearly with gap distance and gap factors between rod-rod gap and rod-conductor gap tended to level offto 1.05.

关 键 词：长空气间隙 操作冲击放电 大气修正系数 下电极高度 导线接地方式 间隙系数 

分 类 号：TM835[电气工程—高电压与绝缘技术]