基于时频谱相似度的高压直流线路行波保护方法  

Traveling wave protection method for HVDC lines based on the time frequency spectrum similarity

作　　者：梁英 杨嘉 李勤新[2] 陈春萌 LIANG Ying;YANG Jia;LI Qin-xin;CHEN Chun-meng(State Grid Qinghai Electric Power Test and Research Institute, Xining 810000,China;China Electric Power Research Institute,Beijing 100192,China;State Grid Qinghai Electric Power Company, Xining 810008,China)

机构地区：[1]国网青海省电力公司电力科学研究院,青海西宁810000 [2]中国电力科学研究院,北京100192 [3]国网青海省电力公司,青海西宁810008

出　　处：《电力科学与技术学报》2019年第2期182-186,共5页Journal of Electric Power Science And Technology

摘　　要：直流输电线路保护系统是支撑直流工程安全稳定运行的保障,中国高压直流线路大多采用信号变化率作为保护判据,在发生高阻接地故障时具有拒动的风险。为此,该文分析直流线路区内与区外故障电流行波的特征,提出一种基于时频谱相似度的高压直流线路行波保护方法。该文所提方法基于直流系统自身固有的结构与参数特征,充分利用故障暂态所产生的电流暂态信号中蕴含的丰富故障信息,在高阻接地故障情况下依然能够准确识别故障区域。The DC transmission line protection system ensures the safe and stable operation of DC engineering protection. In China, the signal gradient criterion is widely utilized in the HVDC project. However, this criterion refuses to operate when the high impedance ground fault occurs. On the background, this paper analyzes the characteristics of fault current traveling wave when the internal fault and external fault occurs in the HVDC line. In addition, a traveling wave protection method is proposed for the HVDC transmission line based on time-frequency spectrum similarity. Considering the inherent structure and parameter characteristics of the DC system, the rich fault information contained in the transient current signal is fully analyzed and investigated, and the fault area is then identified even under the condition of high impedance ground fault.

关 键 词：高压直流线路 行波保护 时频谱 相似度 

分 类 号：TM773[电气工程—电力系统及自动化]