基于熄弧倍增原理的配电网单相接地故障处理  

A Novel Approach Treating Single-Phase Ground Fault in Distribution System

作　　者：刘健[1] 张小庆[1] 李品德[1] 张志华[1] 权立[1] 

机构地区：[1]陕西电力科学研究院,陕西省西安市710054

出　　处：《电网技术》2016年第11期3586-3590,共5页Power System Technology

基　　金：国家电网公司重大科技项目(提高配电网故障处理能力的关键技术研究)~~

摘　　要：为了提高配电网单相接地故障处理的性能,提出一种基于熄弧倍增原理的配电网单相接地故障处理方法,并研制出由控制器、智能消弧柜、中性点接地小电阻及其投切开关组成的单相接地故障综合治理装置。检测到配电网发生单相接地时,智能消弧柜的对应相首先快速合闸接地以转移故障点的电弧,经过适当延时后断开该开关,若电弧不再复燃则完成了瞬时性单相故障的快速处理,若电弧复燃则可判定为永久性单相接地故障,此时投入中性点接地小电阻,达到增大接地点上游零序电流以便于检测的目的,再配合配电自动化系统或零序电流继电保护进行永久性故障处理。采用10 k V真型试验配电网验证了所建议的方法和装置的可行性和有效性,并结合实例对其应用进行了详细说明。To improve single-phase ground fault treatment in distribution systems, a new approach based on arc blowing and zero sequence current increasing was put forward. Corresponding device was developed, composed of a controller, a single-phase arc blower and a resistor connected to neutral point with a switch. Once single-phase ground fault was detected, corresponding single-phase arc blower turned on the switch to ground the phase to blow out the arc. The switch was turned off after a certain time delay. Treatment of an instantaneous fault is thus finished if arc reignition didn＇t occur. Otherwise, it was identified as permanent fault, where the resistor would be connected to neutral point by turning on corresponding switch. Therefore, zero sequence current along up-stream of grounding point is increased remarkably, so that easy to detect. Permanent single-phase ground fault may be treated with coordination of distribution automation system（DAS） or zero sequence current based relay protection. Feasibility and effectiveness of the proposed approach and device was verified with an experiment in a 10 k V distribution system. An example was also given to describe application of the proposed method.

关 键 词：配电网 单相接地 熄弧 瞬时性故障 永久性故障 零序电流 

分 类 号：TM721[电气工程—电力系统及自动化]