Two-dimensional wavelet transformation based transformer partial discharge spectrum denoising method

The invention discloses a two-dimensional wavelet transformation based transformer partial discharge spectrum denoising method. The method includes the steps: (1), inputting a to-be-denoised three-dimensional transformer partial discharge spectrum which is {fm,n; m,n=1, 2,...,k; kdecomposing level j; (3), subjecting the three-dimensional transformer partial discharge spectrum containing noise to two-dimensional wavelet transformation, and decomposing the spectrum into smooth components of the highest decomposing level and detail components of each decomposing level; (4), adopting a BayesShrink threshold to perform threshold quantification processing on the detail components, obtained in the step (3), of each decomposing level for removing noise components, and saving the components as new detail components; (5), performing spectrum reconstruction by utilizing the new detail components obtained in the step (4) and the smooth components, obtained in the step (2), of the highest decomposing level so as to obtain the denoised three-dimensional transformer partial discharge spectrum.