基于行波时域分析和VMD的多分支输电线路故障定位

Fault Location Method for Multi-branch Transmission Line Based on Traveling Wave Time Domain Analysis and VMD

考虑多分支输电线路的行波时域特性,提出一种基于行波时域分析和VMD的多分支输电线路故障定位方法,利用主干线路时域信息和支路频域信息进行故障定位。首先,分析了主干线路的行波时域特性,根据故障后到达主干线路首末端的初始行波时间差判定故障区段;然后,利用VMD分解故障电压行波信号,通过MUSIC谱估计获得其固有频率主成分;最后,利用初始行波时间差、固有频率主成分与故障距离的关系来确定主干线路和分支线路故障位置。仿真试验结果表明,该方法提高了行波时域分析的可行性,避免了固有频率的频谱混叠问题,具有较高的定位精度,为多分支输电网的故障定位提供了新思路。

Considering the traveling wave time domain characteristics of multi-branch transmission line,a fault location method for multi-branch transmission line based on traveling wave time domain analysis and VMD was proposed.This method utilizes the time domain information of the main line and the frequency domain information of the branch line to locate the fault.Firstly,the traveling wave time domain characteristics of the main line was analyzed,and the fault section was determined according to the difference time between the initial traveling wave reaching the first and ends of the main line after the fault.Then,the VMD algorithm was used to decompose the fault voltage traveling wave,and the natural frequency was obtained by MUSIC spectrum estimation.Finally,the fault location of the main line and the branch line was determined respectively by using the relationship between the initial traveling wave time difference,the natural frequency principal components and the fault distances.The simulation results show that the proposed method not only improves the feasibility of traveling wave time domain analysis,but also avoids the spectral aliasing problem of natural frequency.It has high ranging accuracy and provides a new idea for fault location of multi-branch transmission network.