Noise reduction method and system for medium-voltage carrier signal through wavelet packet combining singular value

Abstract

The embodiment of the invention discloses a noise reduction method and system for a medium-voltage carrier signal through a wavelet packet combining a singular value, and the method comprises the steps: obtaining the medium-voltage carrier signal of a power line in a medium-voltage power distribution network; carrying out the sampling of the medium-voltage carrier signal through an isolation channel digital storage oscilloscope, and obtaining N sampling points; selecting a wavelet function and a decomposition layer number, which are corresponding to the medium-voltage carrier signal, carrying out the wavelet packet decomposition of the medium-voltage carrier signal corresponding to N sampling points, and sequentially decomposing the medium-voltage carrier signal into multi-band medium-voltage carrier signals from the low to the high according to the band; keeping the wavelet packet coefficient corresponding to a low-frequency band in the decomposed medium-voltage carrier signals, and carrying out the noise reduction of the wavelet packet coefficients corresponding to a preset number of high-frequency bands; reconstructing the decomposed medium-voltage carrier signals through the wavelet packets, and obtaining the medium-voltage carrier signals after noise reduction. According to the technical scheme of the invention, the method can obtain the smooth noise-reduction medium-voltage carrier signals.

Description

technical field [0001] The invention relates to the technical field of signal noise reduction, in particular to a medium-voltage carrier signal noise reduction method and system using wavelet packets combined with singular values. Background technique [0002] The wavelet packet has good time-domain localization function and excellent band-pass filtering function, and it is a finer signal decomposition method than wavelet decomposition. Therefore, wavelet packet analysis has a wider application value than wavelet analysis, especially for the The signal can be better filtered. [0003] In the prior art, wavelet packets are often used to perform noise reduction processing on medium-voltage carrier signals. Specifically, medium-voltage carrier signals in high-frequency bands with high noise ratios in medium-voltage carrier signals at each sampling time are filtered out, and then The medium-voltage carrier signal in the low-frequency band at each moment is spliced ​​and reconst...

AI Technical Summary

Problems solved by technology

[0005] Embodiments of the present invention provide a medium-voltage carrier signal denoising method and system using wavelet packets combined with singular values ​​to solve the problem that the signal waveform obtained by wavelet packet filtering in the prior art is not smooth, the signal quality is poor, and it is difficult to reflect medium-voltage The problem of the real situation of the carrier signal

Images