基于行波特征频率的配电网混合线路故障定位方法

Fault Location Method for Hybrid Lines Based on Traveling Wave Characteristic Frequency in Distribution Network

为了避免架空线-电缆混合线路故障定位中波速折算和波头提取的问题,提出了基于行波特征频率和粒子群优化小波神经网络的故障定位方法。利用故障点暂态行波的路径特征频率与故障位置一一对应这一特点,采用小波多分辨率分析提取行波特征频率信息,构建小波神经网络拟合暂态行波各频段能量百分比与故障位置的关系,并用粒子群算法优化小波神经网络,从而提高了收敛速度和定位精度。仿真结果表明,该方法在复杂混合线路中有较高的故障定位精度,且基本不受故障类型、故障初始相角和过渡电阻的影响。

To avoid wave speed conversion and wave head extraction in the fault locating of the overhead line-cable hybrid line system,a fault location method based on traveling wave characteristic frequency and particle swarm optimized wavelet neural network is proposed in this paper.The transient signal traveling through each path contains certain characteristic frequency.Taking advantage of this characteristic,the multiresolution analysis is used to extract the characteristic frequency,and a wavelet neural network is constructed to fit the relationship between the energy percentage of each frequency band and the fault location.The particle swarm algorithm is used to optimize the wavelet neural network,thus the convergence speed and positioning accuracy are improved.The simulation results show that the proposed method has high fault location accuracy in complex hybrid lines,and is not affected by fault type,inception angle and transition resistance.