GIS Partial Discharge Fault Detection Method Based on Improved Wavelet Threshold Denoising

Abstract

The invention discloses a GIS partial discharge fault detection method based on improved wavelet threshold value denoising. The method of the present invention comprises the following steps: performing wavelet transformation on the data detected by the UHF sensor, selecting the dB4 mother wavelet to perform four-level decomposition on the sensor detection data, and obtaining wavelet coefficients at each scale; quantifying the threshold of the wavelet decomposition coefficient, and selecting After being determined, the wavelet coefficients smaller than the threshold are removed, and the wavelet coefficients larger than the threshold are processed by the threshold function, and then the coefficients of each layer after the threshold function processing are obtained; the processed coefficients of each layer are reconstructed through wavelet inverse transform, so as to realize Wavelet denoising. Compared with the traditional soft and hard threshold noise reduction algorithms, the present invention not only further improves the signal-to-noise ratio after noise reduction, but also reduces the variance, so that the processed signal waveform is closer to the original partial discharge signal, which is conducive to subsequent discharge Identification of defect types.

Description

technical field [0001] The invention relates to GIS partial discharge detection technology, in particular to a GIS partial discharge fault detection method based on improved wavelet threshold value denoising. Background technique [0002] GIS has compact structure and high reliability, and is widely used in power system. There are many types of GIS faults, including mechanical faults, insulation faults, and line faults. According to the fault statistics of equipment operation over the years, insulation faults caused by long-term operation of circuit insulators in harsh operating environments such as high temperature and high pressure account for about 80% of the total fault types, and partial discharge is the main cause of insulation defects in power equipment. Therefore, timely detection The latent faults inside GIS are of great significance to the safe operation of equipment. [0003] UHF partial discharge detection technology is a method of analyzing and diagnosing loca...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to overcome the above-mentioned defects in the prior art, and provide a GIS partial discharge fault detection method based on improved wavelet threshold denoising, which uses a UHF partial discharge sensor to detect the discharge under the interference of strong white noise Data, the processed signal waveform is closer to the original partial discharge signal, so as to facilitate the subsequent identification of discharge defect types

Images