行波距离保护中识别第2个反射波性质的新方法  

A New Scheme to Identify the Nature of the Second Reflection Wave in Travelling Wave Based Distance Protection

作　　者：高效海[1] 何奔腾[1] 王慧芳[1] 张雪松 张波[1] 

机构地区：[1]浙江大学电气工程学院,浙江省杭州市310027 [2]浙江省电力公司电力科学研究院,浙江省杭州市310014

出　　处：《电网技术》2013年第5期1477-1482,共6页Power System Technology

基　　金：国家电网公司科技项目(ZDK077-2011)

摘　　要：行波距离保护中存在对端母线反射波影响测距准确性的问题,为此提出一种新的可以统一识别各种接地故障下第2个反射波性质的方法,并给出实现方案。首先通过相模变换,提取初始行波和第2个反射波的0模分量极性以及3个分别以A、B、C相为基准的1模分量极性。然后将初始行波0模分量和3个1模分量的极性关系与第2个反射波0模分量和3个1模分量极性关系进行比较,如果至少有2组关系相同,则为故障点的反射波;如果最多只有1组关系相同,则为对端母线的反射波。大量仿真表明,该方案能正确识别各种接地故障第2个反射波的性质,且不受两端母线结构的影响。In traveling wave based distance protection there is a problem that the reflected wave from opposite busbar affects the accuracy of fault location. Therefore a new method, by which the features of the second reflected wave under various types of earth faults that can be uniformly recognized, is proposed, and corresponding realizing scheme is given. Firstly, through phase-mode transformation the mode-O component polarities of initial traveling wave and the second reflected wave as well as their three mode-1 polarities taking phase A, phase B and phase C as the benchmark are extracted; then the relationship among polarity of mode-O component and polarities of three mode-1 components of initial traveling wave is compared with the relationship among polarity of mode-O component and polarities of three mode-1 components of the second reflected wave, if there are at least two groups possess the same relationship of polarity, the second reflected wave is from the fault point; if there is at most one group possesses the same relationship of polarity, the second reflected wave is from opposite busbar. A lot of simulation results show that the proposed scheme can recognize the features of the second reflected wave due to various types of earth faults, and the recognizations are not affected by busbar structures at both terminals.

关 键 词：行波距离保护 初始行波 故障点反射波 对端母线反射波 

分 类 号：TM77[电气工程—电力系统及自动化]