Analysing time-varying power system harmonics using wavelet transform

This paper presents the possibilities offered by the dyadic-orthonormal wavelet transform used in the multiresolution analysis of voltage- and current-signals. This transform proves to have some advantages over the classical FFT-based algorithms, when used in electric power quality assessment and the analysis of waveforms. Practical examples using waveforms generated by energy saving lighting equipment, remote-control signals and an adjustable speed drive, are presented.