research paper
Wavelet-Transform-Based Algorithm for Harmonic Analysis of Power System Waveforms
Javid Akhtar, Md Imran Ali Baig
Ghousia College of Engineering
Ramanagaram-571511
mirzaimranalibaig@gmail.com
Abstract
The concept is to develop an approach based on wavelet transform for the evaluation of harmonic contents of power system waveforms. This new algorithmic approach can simultaneously identify all harmonics including integer, non-integer and sub-harmonics. This algorithm presents features that characterize the power quality disturbances from recorded voltage waveforms using wavelet transform. The discrete wavelet transform has been used to detect and analyze power quality disturbances. The disturbances of interest include sag, swell, outage and transient. Waveforms at strategic points can be obtained for analysis, which includes different power quality disturbances. The wavelet has been chosen to perform feature extraction. The outputs of the feature extraction are the wavelet coefficients representing the power quality disturbance signal. Wavelet coefficients at different levels reveal the time localizing information about the variation of the signal. A wavelet packet transform (WPT) method is introduced as a useful tool for detecting, classifying and quantifying the RMS of testing waveform and harmonic ratio value. The proposed approach can measure the distribution of the RMS of testing waveform with respect to individual frequency bands directly from the wavelet transform coefficients. The harmonic ratio value relative to basic frequency band can be calculated as well. The method is evaluated by its application to both analytical waveform and actual testing waveform data. Keywords: wavelet packet transform (WPT), Discrete Fourier Transform (DFT), Fourier Series (FS), Discrete Wavelet Packet Transform (DWPT), Multi-Resolution Analysis (MRA)
1. Introduction
Mathematical transformation are applied to signals to obtain a further
Javid Akhtar, Md Imran Ali Baig
Ghousia College of Engineering
Ramanagaram-571511
mirzaimranalibaig@gmail.com
Abstract
The concept is to develop an approach based on wavelet transform for the evaluation of harmonic contents of power system waveforms. This new algorithmic approach can simultaneously identify all harmonics including integer, non-integer and sub-harmonics. This algorithm presents features that characterize the power quality disturbances from recorded voltage waveforms using wavelet transform. The discrete wavelet transform has been used to detect and analyze power quality disturbances. The disturbances of interest include sag, swell, outage and transient. Waveforms at strategic points can be obtained for analysis, which includes different power quality disturbances. The wavelet has been chosen to perform feature extraction. The outputs of the feature extraction are the wavelet coefficients representing the power quality disturbance signal. Wavelet coefficients at different levels reveal the time localizing information about the variation of the signal. A wavelet packet transform (WPT) method is introduced as a useful tool for detecting, classifying and quantifying the RMS of testing waveform and harmonic ratio value. The proposed approach can measure the distribution of the RMS of testing waveform with respect to individual frequency bands directly from the wavelet transform coefficients. The harmonic ratio value relative to basic frequency band can be calculated as well. The method is evaluated by its application to both analytical waveform and actual testing waveform data. Keywords: wavelet packet transform (WPT), Discrete Fourier Transform (DFT), Fourier Series (FS), Discrete Wavelet Packet Transform (DWPT), Multi-Resolution Analysis (MRA)
1. Introduction
Mathematical transformation are applied to signals to obtain a further