摘要
可自恢复性单相接地故障点的电弧是否能自然熄灭的决定因素是接地故障残流的大小。以降低单相接地故障点的残流为出发点,从理论上分析了谐振接地系统残流产生的原因:消弧线圈自动跟踪补偿只能有效地降低零序回路的无功电流,不能降低零序回路的有功电流。通过仿真计算得出结论:消弧线圈分布安装是降低谐振接地系统接地故障点残流有功分量的有效方法。针对我国6 kV和10 kV中压配电网一般均为△接线,无辅助中性点供消弧线圈接入的特点,设计了一种新颖的消弧线圈。该消弧线圈为三相五柱电抗器结构,通过调节两边柱的气隙大小改变补偿电流的大小,结构简单,适合于分布安装。实验室试验证明其补偿电感线性度好、补偿效果好。
The self-extinguishing of the arc caused By a single- phase grounding fault depends mainly on the amplitude of the residual current at grounding point. To reduce the residual current, the reason of residual current generation in resonant grounding system is analyzed theoretically：the automatic arc-suppression coil can only compensate the zero-sequence reactive current,but not the active current. Simulative calculation points out that,the decentralized compensation is an effective way to reduce the active components of residual current. For 6 ＆ 10 kV distribution networks in China are wired in △ type and there is no auxiliary neutral point for arc-suppression coil,a new -type arc- suppression coil is developed,which is a three- phase- five- column reactor and the compensation current is controlled By adjusting the gaps of two side columns. It is fitted for decentralized compensation with simple structure. The lab experiments show its fine inductance linearity and effective compensation performance.
出处
《电力自动化设备》
EI
CSCD
北大核心
2007年第11期87-90,共4页
Electric Power Automation Equipment
关键词
消弧线圈
单相接地故障
中性点接地
arc- suppression coil
single- phase grounding fault
neutral grounding
