基于波形群灵敏角特征的输电线路故障单端行波辨识与测距

Single-ended Traveling Wave Surge Identification and Fault Location for Transmission Lines Based on the Sensitive Angle Characteristic of Waveshape With Multiple Wavefronts

针对输电线路单端行波测距难以可靠、有效辨识第二个波头的不足,该文提出基于波形群灵敏角检测的单端行波辨识与测距方法。首先,对线路故障波过程的解析和规律分析,发现波头局部波形呈现灵敏角和非轴对称性的特点。进而提出利用Radon变换变角度投影检测最灵敏角并判别最灵敏角两侧非轴对称特性,实现单端故障初始行波及多次同极性行波群的可靠辨识。最后,基于多次同极性行波到达时差构造多测距算式,输出最合理测距结果。所提方法将时域波头辨识转化为波形图像空间域最灵敏变化方向和几何轴对称性的检测,抗干扰能力强,大幅提升检测可靠性和后续波头的识别能力,提升单端测距算式冗余性。大量实测和仿真数据测试表明,算法有效、可靠、直观,适用范围广,为单端行波分析故障测距及扩展应用提供了新思路。

It is difficult to identify the second wavefront reliably and effectively during the single-ended traveling waves fault locating process for transmission lines.In order to solve these problems,a single-ended traveling wave identification and fault location approach based on the sensitive angle characteristic of waveshape is proposed in this paper.First,the regularity of fault induced traveling waves process on transmission lines is analyzed.The sensitive angle and non-axisymmetric characteristics of the wavefront in local waveshape view is found.Then,the algorithm of identifying the initial traveling wave and multiple homopolar traveling waves observed at single terminal is proposed by using Radon transform variable angle projection to detect the most sensitive angle and identify the non-axisymmetry on the both sides of the most sensitive angle.Finally,multiple fault locating formulas are constructed based on multiple homopolar traveling waves’arrival time difference.The final reasonable result is confirmed.The proposed algorithm transforms the wavefront identification from traditional time-domain series analysis into detection of the most sensitive change direction and the symmetry of geometry in the spatial domain of waveform graph,with high anti-interference capability,which greatly improves the reliability of the surge detection and the identification ability of subsequent traveling waves.And the redundancy of single-ended traveling wave fault location formula is also enhanced.Extensive field data recordings and digital simulation tests show that the proposed algorithm is effective,reliable,and intuitive,with wide range of applications.This paper provides new ideas for single-ended traveling wave fault location and its extended applications.