基于行波衰减理论的多端直流网络故障定位  

Fault Location of Multi-terminal DC Network Based on Traveling Wave Attenuation Theory

作　　者：张怿宁[1] 方苏 罗国敏[2] 刘燕莹 黑嘉欣 ZHANG Yi-ning;FANG Su;LUO Guo-min;LIU Yan-ying;HEI Jia-xin(Maintenance Test Center of China Southern Power Grid Ultra High Voltage Company, Guangzhou 510663, China;School of Electrical Engineering, Beijing Jiaotong University, Beijing 100044,China)

机构地区：[1]中国南方电网超高压公司检修试验中心,广州510663 [2]北京交通大学电气工程学院,北京100044

出　　处：《科学技术与工程》2020年第32期13240-13248,共9页Science Technology and Engineering

基　　金：南网重点科技项目(CGYKJXM20180540)。

摘　　要：多端环型直流系统线路发生故障时,故障行波传播到故障线路端点的行波记录仪存在多种路径。若故障行波到达故障线路两端行波记录仪的最短路径不是沿着故障线路向两端传播的,而是经过相邻线路向端点传播的,传统上利用初始行波进行故障定位的方法不再适用,存在盲区问题。为解决盲区问题,研究了行波的衰减特性。故障行波经相邻线路到达故障线路的行波记录仪时,受线路分支的影响,行波的波头幅值发生衰减,而沿故障线路直接传播时,未经过分支行波波头幅值变化大。因此,提出基于行波衰减理论的多端直流网络故障定位方法。根据波速随频率变化特性,提出参考波速的想法和在线测量波速的方法。在PSCAD中搭建四端直流输电线路模型,调整故障类型以及故障位置进行仿真分析,结果表明此方法可以实现快速在线定位,可见所提方法解决盲区问题的适用性及准确性。When the line failed in a multi-terminal ring-type DC system,there were multiple paths for the fault traveling wave propagating to recorder of the line endpoint.If the shortest path of traveling wave to the traveling wave recorder at both ends of the fault line was not along the fault line but through the adjacent line to the one end of the fault line,the traditional method of fault location using the initial traveling wave was no longer applicable,and there was a problem of blind zone.In order to solve the blind zone problem,the attenuation characteristics of traveling waves were studied.When the fault traveling wave reached a traveling wave recorder of the fault line via the adjacent line,the wave head amplitude of the traveling wave was attenuated by the influence of line branch.However,when the traveling wave propagated directly along the fault line,the wave head amplitude of the traveling wave without passing through the branch changed greatly.Therefore,a fault location method of multi-terminal DC network based on traveling wave attenuation theory was proposed.In addition,according to the frequency characteristics of wave velocity,the idea of reference wave velocity and the method of measuring wave velocity online were proposed.A four-terminal HVDC transmission line model was built in PSCAD,and fault types and fault locations were adjusted for simulation and analysis.The results show that the method can achieve online fault location quickly,which shows applicability and accuracy of the proposed method to solve the blind zone problem.

关 键 词：盲区 行波衰减理论 多端直流网络 在线测量波速 故障定位 

分 类 号：TM721[电气工程—电力系统及自动化]