基于小波去噪和暂态电流能量分组比较的小电流接地选线新方法  

A new method for fault line selection based on wavelet de-noising and transient current energy grouping comparison in ineffective grounding system

作　　者：周登登[1] 刘志刚[1] 胡非[1] 白玮莉 

机构地区：[1]西南交通大学电气工程学院,四川成都610031

出　　处：《电力系统保护与控制》2010年第7期22-28,共7页Power System Protection and Control

基　　金：教育部霍英东青年教师基金资助项目(101060);四川省杰出青年基金项目(07JQ0075)

摘　　要：分析了故障选线的现状和基于故障暂态电流选线的优势,提出了消弧线圈接地系统中基于小波去噪和暂态电流能量分组比较的选线新方法。该方法先将含噪电流信号进行小波软阈值消噪,然后将去噪后的信号排序,分组求能量并归一化,接着对其进行阈值处理即可得到各个出线的累加变量值,比较这些值的大小,便可选出故障线路。该方法不受补偿度、故障地点、过渡电阻、负荷大小和故障相角的影响,原理简单、可靠、计算量小、抗干扰能力强,仿真证明了该方法的有效性。This paper analyses the development of the fault line selection and the advantages of using transient current for fault line selection, then proposes a new fault line selection method based on wavelet soil-threshold de-noising and transient current energy grouping comparison in arc suppression coil grounded system. It eliminates the noise in the current firstly, and then sorts the denoised signal, and makes the normalized energy of each two zero sequence currents. Through comparing the normalized energy with a given threshold, the accumulation variable value （AW） of each outlet can be gained. The fault line will be selected by comparing these AVVs. This method has the advantages of simple principle, reliability, low computational complexity, and strong anti-interference ability. It immunes from the influences of compensation degree, fault location, phase angle, load, and fault transient resistance. The simulation results verify the effectiveness of proposed method.

关 键 词：故障选线 暂态电流 消弧线圈接地系统 小电流接地 小波软阈值消噪 

分 类 号：TM862[电气工程—高电压与绝缘技术]