基于中电阻法的小电流接地选线方法研究  

Research on fault line selection method based on medium resistance for low current grounding system

作　　者：吴建宇 WU Jianyu(Fuzhou Minjiang Park Office,Fuzhou 350000)

机构地区：[1]福州市闽江公园管理处,福州350000

出　　处：《电气技术》2023年第10期17-22,共6页Electrical Engineering

基　　金：国家自然科学基金(51777106)。

摘　　要：变电站小电流接地选线存在正确率偏低、漏报率和误报率高等问题,直接影响配电网主站研判结果,导致无法实现故障自动隔离、供电可靠性大大降低。鉴于此,本文提出一种通过采用消弧线圈控制器控制中电阻投切,并配合投入变电站10kV线路零序过电流保护及10kV柱上开关的零序过电流保护,快速切除单相接地故障的方法。该方法充分发挥中电阻选线的优点,可有效提高配电网单相接地时选线选段的准确率,且具有改造投资省、效率高,改造时停电时间短、停电范围小的优点,能有效弥补中电阻长时间投入并流过短路电流时易烧毁的缺点。The low current grounding line selection in the substation has problems such as low accuracy rate,high omission rate and high false alarm rate,which directly affect the evaluation results of the main station of the distribution network.As a result,the automatic failure isolation cannot be realized,and the power supply reliability is greatly reduced.This paper presents a method to quickly remove the single phase grounding faults by using the arc-reducing coil controller and combining the 10kV line zero-sequence over-current protection and the 10kV column switches zero-sequence over-current protection.This method utilizes the advantages of the medium resistance to effectively improve the accuracy of line selection when single phase grounding.It has the advantages of saving investment,high efficiency,short power outage time and small power failure range.At the same time,it can effectively make up for the disadvantages of medium resistance being easily burnt out when it is put into operation for a long time and flows through short-circuit current.

关 键 词：小电流接地选线 中电阻法 配电网 单相接地故障 

分 类 号：TM862[电气工程—高电压与绝缘技术]