不同频带下电压故障行波极性的一致性分析  

Polarity Consistency Analysis of Voltage Transient Traveling-wave in Different Frequency Band

作　　者：王世勇[1] 董新洲[1] 施慎行[1] 

机构地区：[1]电力系统国家重点实验室,清华大学电机系,北京市100084

出　　处：《电力系统自动化》2011年第20期68-73,共6页Automation of Electric Power Systems

基　　金：国家自然科学基金重点资助项目(50937003);国家自然科学基金资助项目(51007045);国家科技支撑计划资助项目(2006BAJ16B02);高等学校博士学科点专项科研基金资助项目(200800031034);电力系统国家重点实验室重点基金资助项目(SKLD09M04)~~

摘　　要：输电线路故障后产生的电压故障行波是一个宽频带信号。由于电容式电压互感器不能有效传变宽频带电压行波信号,给行波保护投入电力系统实际应用带来困难。文中应用数学分析工具——小波变换,以及小波变换的多分辨率分析特性,将电压故障行波分解成多个频带信号,并研究了各个频带下电压故障行波初始极性之间的关系。研究结果表明:电压故障行波各频带信号的初始极性具有一致性,而电压故障行波中工频分量的初始极性与电压故障初始行波的波头极性一致。这一结论为新型方向比较式行波保护原理的建立提供了理论基础。Voltage fault traveling-wave after transmission line faults is a wide frequency band signal.It brings about difficulties for traveling-wave based protection to be applied into power systems because capacitor voltage transformer cannot transmit wide frequency band voltage traveling-wave effectively.The mathematic tool—wavelet transform is utilized,and its multi-resolution signal decomposition characteristic is used to decompose the voltage fault traveling-wave into different frequency band signals.Besides,the polarity relationships among the initial voltage fault traveling-wave in different frequency bands are studied.The studied results show that the initial polarities of voltage fault traveling-wave in different frequency band signals are consistent,and the initial polarities of power frequency components in voltage fault traveling-wave are consistent with the wave front polarity of the initial voltage fault traveling-wave.This conclusion provides theoretic basis for new traveling-wave based directional comparative protection principle.

关 键 词：输电线路 电压故障行波 小波变换 多分辨率分析 行波保护 

分 类 号：TM773[电气工程—电力系统及自动化]