基于行波固有频率的高压直流输电线路故障定位

摘要

A new fault location method is proposed using single-end traveling wave frequency information for high voltage direct current (HVDC) transmission lines. Different from the traditional partial differential equations based methods, the proposed method is based on the traveling wave's natural frequency. The transient signals are analyzed to extract the natural frequencies using multiple signal classification (MUSIC) after the fault occurred at the line. The fault distance can be calculated with the relationship among the fault distance, the dominant natural frequency and the terminal conditions of transmission line. A simulation model of 800 kV ultra high voltage direct current (UHVDC) transmission system is built in PSCAD/EMTDC. Various transmission line fault situations are considered to locate the fault point with different transition resistance. The results confirm that the proposed method is feasible and accurate.%提出了一种仅利用单端电压暂态量频谱信息进行直流输电线路精确故障定位的新方法.与传统的基于偏微分方程的行波分析方法不同,文中采用的基于行波固有频率主成分的测距方法不受行波波头识别等的限制,只需要故障后的一段暂态电压信息,通过对暂态电压信息的频谱分析,得到行波固有频率的主成分,然后结合故障线路边界条件计算出故障距离.在PSCAD/EMTDC中建立高压直流输电系统模型,在此基础上针对不同过渡电阻下的单极接地故障对该算法进行了不同运行方式下的仿真验证,结果表明该算法在高压直流输电线路上具有很好的适应性和较高的定位精度.