550 kV罐式断路器灭弧室偏心引起的悬浮放电计算  

Calculation on Floating Discharge Caused by Arc Extinguish Chamber Bias of 550 kV Tank-type Circuit Breaker

作　　者：李爽 李斌 唐佳能 郭志楠 郎福成[2] 郎业兴 LI Shuang;LI Bin;TANG Jianeng;GUO Zhinan;LANG Fucheng;LANG Yexing(State Grid Liaoning Electrical Power Research Institute,Shenyang 110006,China;High Voltage and Large Current Laboratory of State Grid Corporation,Shenyang 110006,China)

机构地区：[1]国网辽宁省电力有限公司电力科学研究院,沈阳110006 [2]国家电网公司高电压强电流实验室,沈阳110006

出　　处：《高压电器》2019年第6期45-50,共6页High Voltage Apparatus

摘　　要：为了研究某550 kV罐式断路器在运行中产生悬浮电位放电的原因,提出改进措施,根据工程力学原理,分析了绝缘台屏蔽环的受力情况,采用流注击穿理论提出了间隙击穿的临界距离判据,最后用ELECNET有限元分析方法验证了判据的有效性。研究表明:灭弧室装配偏心导致绝缘台屏蔽环受力不均,其在外力作用下与端盖支撑法兰分离形成悬浮放电间隙;当此间隙d在0<d≤1.19 mm范围内会发生悬浮放电,大于1.19 mm则不会发生间隙击穿;通过在绝缘台屏蔽环与端盖支撑法兰之间采用等电位连接线,并在两者间设置1 mm厚的绝缘胶带可有效避免悬浮放电的发生。To reveal the floating discharge in a 550 kV tank-type circuit breaker and propose a countermeasure,the forces on the insulator shielding ring is analyzed according to the principles of engineering mechanics.A critical breakdown distance criterion is proposed by adopting the stream breakdown theory,and the effectiveness of the criterion is verified via ELECNET.The results show that arc extinguish chamber bias causes uneven force on the insulator shielding ring,and a gap between the shielding ring and the end closure sustaining flange will form under external force.Only when the distance of the gap is in the range from 0 to 1.19 mm,floating discharge will occur.The floating discharge can be avoided by using an equipotential wire to connect the insulator shielding ring and the end closure sustaining flange,and setting an insulating tape with thickness of 1 mm betweenthem.

关 键 词：罐式断路器 灭弧室偏心 绝缘台屏蔽环 端盖支撑法兰 悬浮放电 

分 类 号：TM561.5[电气工程—电器]