脉冲前沿对电缆故障定位行波到达时间的影响研究

Influence of Pulse Edge on the Time of Arrival for Cable Fault Location Application

在电缆等传输线的故障定位中,信号脉冲前沿与理想波形相差很大,会直接影响行波到达时间的准确估计。为此,分别引入介质色散、带宽受限和加性干扰作为影响因素,建立了电缆上行波脉冲前沿理论模型,并在此基础上研究了基于归一化的阈值比较、脉冲能量拐点和赤池信息准则三种行波到达时间提取算法,利用蒙特卡洛仿真比较了三种算法的准确性与分散性,获得了脉冲前沿对行波到达时间估计的统计规律。

In the fault location of transmission lines such as cables,the pulse edge might vary greatly from the ideal waveform,resulting in inaccuracy of estimation for the time of arrival(ToA).Therefore,this paper establishes a theoretical model of traveling waves on cables by considering dielectric dispersion,bandwidth limitation and additional noise distribution as the influencing factors.Based on this model,the three algorithms for time of arrival extraction,i.e.normalized threshold comparison,energy change point detection and the Akaike information criterion(AIC)are studied,and the performance is investigated based on Monte Carlo simulated method.As a result,the statistical regularity for the influence of pulse edge on the estimation of ToA can be acquired.