Abstract :
This paper deals with the problem of estimation of
voltage and current spectrum, especially harmonics, in the field
of electrical power engineering. After description of hitherto used
methods, a method of the combined wavelet-Fourier spectrum
analysis has been proposed. The method consists in applying the
wavelet transform for samples of the original signal, then using
digital Fourier transform to the results for spectrum extraction.
As a result, the significantly decreased number of needed multiplications
is observed. A comparison of the method and fast
Fourier transform, as well as the recently introduced wavelet
packet decomposition, has been carried out. Finally, the results
of experimental research have been shown and commented on.
During research, various kinds of wavelet “mothers” and varying
filter length have been taken into consideration.
