Application of Wavelets for Study of Harmonic Propagation in Distribution Networks

This paper demonstrates the applicability of wavelet transforms in the analysis of harmonic distortion propagation in distribution networks. A laboratory experiment involving actual low-voltage feeder and several non-linear loads is proposed for this study. The method is based on the processing of synchronized current and voltage waveforms captured at multiple points of the power network by distributed measurement system with high accuracy. The harmonic propagation phenomena is studied with different types of wavelet transforms, namely decimated discrete wavelet transforms, wavelet packet transforms and continuous wavelet transforms. Advantages of each of the transforms are explained. Together, they form a coherent analysis algorithm culminating in localization of dominant harmonic source in the distribution grid.