As the nonlinear load increases,a large number of harmonic will back to fill the grid which may result in the power pollution and measuring inequality. However,the traditional fast Fourier transform( FFT) detection methods are difficult to meet the harmonic detection requirements for accuracy due to the limitation of their own technology. Combined with the characteristics of power harmonic form,this paper analyzed the principle of wavelet transform and Fourier transform,and put forward a kind method with do...