A wavelet based model for on-line tracking of power system harmonics using Kalman filtering

In this paper, a new harmonic model based on wavelet transform (WT) is proposed for on-line tracking of power system harmonics using Kalman filtering. The close relation between the wavelet and multiresolution analysis is utilized to express the harmonic amplitudes and phase angles as a sum of wavelet and scaling functions. This new model can be used directly to estimate the harmonic amplitudes and phase angles through solving the coefficients of the wavelet and scaling functions. The model is also combined with Kalman filtering technique to develop an on-line harmonic tracking method. The new model was tested using simulation waveform and was shown to possess better tracking capability compared to the traditional model.