A Fault Location Method Based on Improved Wavelet Denoising for Open-line Fault in the Low-voltage Distribution Network

摘要

In this paper, the traveling wave method is used to accurately locate the open-line fault in the low-voltage distribution network where many branch lines and noise interference exist. An improved wavelet threshold function (TF) method is proposed to reduce the noise of the collected traveling wave signal. Then the wavelet singularity theory is applied to identify the time interval between the injected wave head and the reflected wave head, based on which the location of the open-line fault can be calculated. The actual cable models are built in the PSCAD to represent the power lines of the low-voltage distribution network and the open-line fault simulation results show that the proposed denoising method in this paper can increase the signal to noise ratio (SNR) of the collected traveling wave and improve the accuracy of fault location.