利用信号距离识别的高压直流输电线路保护方案  

HVDC Transmission Line Protection Method Using Signal Distance

作　　者：丁浩寅[1] 邰能灵[1] 郑晓冬[1] 

机构地区：[1]上海交通大学电气工程系,上海200240

出　　处：《高电压技术》2011年第5期1186-1193,共8页High Voltage Engineering

基　　金：国家电网公司科技项目~~

摘　　要：为了改进传统高压直流差动保护的动作可靠性,提出了一种基于信号距离识别的高压直流输电线路保护方案。通过对高压直流输电系统在不同故障情况下线路两端电流变化特征进行分析发现,直流线路发生内部接地故障后的暂态过程中,两端电流变化极性相反,电流波形差异度较高,而在线路外部故障时,两端电流变化极性相同,且电流波形相似度较高。在此基础上,引入信号距离的概念来计算线路两端电流的互距离度,并利用电流的互距离度来判别线路故障。大量仿真结果表明,该方法耐受过渡电阻能力强,可靠性高。To improve the reliability of HVDC differential protection,we proposed a novel HVDC transmission line protection method based on signal distance identification.Through analyzing the transmission line currents at both terminals with different faults in the HVDC system,we found that,during the transient period,the polarity of current change at both terminals was adverse and the dissimilarity was obvious.However,with the faults happened outside the protection zone,the polarity of current change was identical and showed high similarity.Thereby,we introduced the concept of mutual signal distance to distinguish line faults by calculating mutual current distance at both terminals.Lots of simulation results demonstrate that the proposed protection method has good performance.

关 键 词：高压直流输电 信号距离 电流差异 接地故障 过渡电阻 保护 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM773