基于小波算法辨识的小电流接地故障选线  

Line Selection of Small Current Earth Fault Based on Wavelet Algorithm Identification

作　　者：魏巍[1] WEI Wei(Nanjing NR Electric Co.Ltd.,Nanjing 210000,China)

机构地区：[1]南京南瑞继保电气有限公司,江苏南京210000

出　　处：《微型电脑应用》2022年第4期96-99,共4页Microcomputer Applications

基　　金：国家电网公司科技项目(SGXJDK00PJJS2000062)。

摘　　要：由于配电网络结构复杂,发生单相接地故障时产生过电压影响系统的正常运行,故障电流微弱、接地电弧不稳定导致接地故障检测精度不高。为此分析小电流发生接地故障时系统零序电流和零序电压的特性,明确相位和方向上的关系,设计出小电流接地故障定位系统,根据输变电线路的暂态零序电流确定故障位置。在输变电线路中安装馈线终端单元采集故障线路的电流电压数据并传输到调度端主站,利用小波包分解算法分析零序电流中有用的特征信号。实验结果显示,这种小电流接地故障定位系统对故障线路的零序电流的采集精度更高,故障选线时间最短。Because of the complex structure of distribution network,the overvoltage of single-phase grounding fault will affect the normal operation of the system.The weak fault current and the unstable grounding arc will lead to the low accuracy of grounding fault detection.The characteristics of zero sequence current and zero sequence voltage of the system are analyzed when small current grounding fault occurs,the relationship between phase and direction is clarified,a small current grounding fault location system is designed,and the fault location is determined according to the transient zero sequence current of the transmission and transformation line.The feeder terminal unit is installed in the transmission and transformation line to collect the current and voltage data of the fault line and transmit it to the dispatching terminal master station.The wavelet packet decomposition algorithm is used to analyze the useful characteristic signals in the zero-sequence current.The experimental results show that the zero-sequence current acquisition accuracy of the fault line is higher and the fault line selection time is the shortest.

关 键 词：单相接地故障 零序电流 馈线终端单元 小波分解 

分 类 号：TP37[自动化与计算机技术—计算机系统结构]