基于附加直流的选择性低压漏电保护实现方法  

Implementation method of selective low-voltage leakage protection based on additional direct current

作　　者：吴骞 周劭亮[1,2,3] WU Qian;ZHOU Shaoliang(State Grid Electric Power Research Institute,NARI Group Corporation,Nanjing 211006;NARI Technology Co.,Ltd,Nanjing 211006;State Key Laboratory of Smart Grid Protection and Operation Control,Nanjing 211006)

机构地区：[1]南瑞集团公司(国网电力科学研究院),南京211006 [2]国电南瑞科技股份有限公司,南京211006 [3]智能电网保护和运行控制国家重点试验室,南京211006

出　　处：《电气技术》2022年第5期86-89,94,共5页Electrical Engineering

摘　　要：选择性是低压漏电保护的基本要求之一,也是衡量低压漏电保护是否合格的标准之一。本文针对常规带附加直流部件的低压漏电保护的缺点,提出一种新型基于附加直流的选择性保护实现方法。利用安装在支路上的交直流采样元件采集并计算各支路交直流电流量,根据交流量和直流量的大小及方向,通过特定算法选择故障支路。这种判别方法解决了附加直流没有选择性的问题,具有结构简单、装置数量少、适用性强、易于扩展、可靠性高等优点,能满足低压漏电保护的选择性要求。Selectivity is one of the basic requirements of low-voltage leakage protection,and it is also one of the standards to measure whether low-voltage leakage protection is qualified.In this paper,the shortcomings of conventional low-voltage leakage protection with additional direct current(DC)components are discussed,and a new implementation method of selective protection based on additional DC is proposed.The alternating current(AC)and DC sampling components installed on the branch are used to collect and calculate the AC and DC current of each branch,and select the faulty branch through a specific algorithm according to the magnitude and direction of the AC and DC current.This discrimination method solves the problem of no selectivity of additional DC,which has the advantages of simple structure,small number of devices,strong applicability,easy expansion,and high reliability,and can meet the selective requirements of low-voltage leakage protection.

关 键 词：低压漏电 继电保护 附加直流 选择性 

分 类 号：TD611[矿业工程—矿山机电] TM77[电气工程—电力系统及自动化]