SF6断路器开断并联电抗器的截流过电压及其特性分析
孙秋芹 李庆民 王 冠 刘洪顺 邹振宇
(1．山东大学电气工程学院 济南 250061 2．山东电力工程咨询院 济南 250100)
摘要 断路器开断并联电抗器时会引起截流，产生严重的过电压。针对带中性点小电抗的并联电抗器，通过建立等效电路从理论上分析了其开断过程的过电压特点，阐明了拍频振荡产生的机理，给出了近距离开断和带长线开断并联电抗器时拍频振荡频率随电抗器参数变化的的三维图像。基于我国某一条750kV输电线路的具体参数，通过弓J入较准确的开关电弧模型，分析了带长线和近距离开断并联电抗器两种工况下操作过电压的具体特征。研究结果为超、特高压输电线路的建设与运行提供了有价值的参考依据。
关键词：并联电抗器开断 中性点电抗 电弧模型 拍频振荡
中图分类号：TM721．1
Characteristic Analysis of the Shunt Reactor Switching Over—Voltages Interrupted by SF6 Circuit Breakers W ith Chopping Current
Sun Qiuqin Li Qingmin Wang Guan Liu Hongshun Zou Zhenyu
(1．Shandong University Jinan 25 006 1 China 2．Shandong Electric Power Consultancy Institute Jinan 250100 China)
Abstract Shunt reactor interruption by circuit breakers may produce current chopping and cause severe overvoltages．The four—legged reactor interrupting transients were elucidated with equivalent circuit analysis，and the mechanism of beat frequency oscillation was also characterized，further，a 3-D portfolio of the beat frequency，specifically regarding shunt reactor interrupting with either a short line
distance or a long transm ission line，was given to describe the variation trend versus the shunt reactor’S parameters．Based on the available parameters from an installed 750kV transmission line in China， simulations of the four-legged reactor interruption process were carried out with adoption of an appropriate arc m odel for SF6 circuit breakers，and the scenario of the switching overvoltages was presented for two different kinds shunt reactor interrupting．The research results present useful
reference for future construction and operation of the extra high voltage(EHV)and ultra high voltage(UHV)transmission lines．
K eywords- Shunt reactor interrupting，neutral reactor,arc model，beat frequency oscillation
2010年2 月 第25卷第2期 电工技术学报
发表于 2010-12-1 05:31:56
