基于SR-WT的输电线路双端故障定位方法

电力系统中行波在传输过程中往往伴随着大量的高频噪声,导致进行故障测距时信号波头不易识别,从而产生测距误差。对此,提出一种基于随机共振和小波变换(SR-WT)的故障测距方法,即先通过随机共振处理含噪信号,将噪声的能量转移到行波信号上,从而实现初步减弱噪声信号提高行波信号的功能;再通过小波变换进一步分解得出所需行波信号波头信息,进而通过双端法进行故障测距。仿真试验结果表明,该方法能够在强噪声干扰下准确提取出所需的行波信号信息,有利于提高测距精度。

Two-terminal Fault Location Method for Transmission Lines Based on SR-WT

In power systems, traveling waves are often accompanied by a large amount of high-frequency noise in the process of transmission, which makes the signal difficult to be identified in performing fault location, resulting in ranging error. For this phenomenon, a fault location method for transmission lines is proposed based on stochastic resonance and wavelet transform. The method first detects the signal by stochastic resonance. The energy of noise is transferred to the traveling wave signal to realize the function of initially weakening the noise signal and improving the traveling wave signal. Then the wave information of traveling wave signal is obtained by decomposition of wavelet transform, and fault location is achieved by two-terminal method. The simulation result shows that the method can extract traveling wave signal information accurately under strong noise interference, and is beneficial to improve the ranging accuracy.