Detection, Measurement and Classification of Power Quality Disturbances in Distribution Systems

Detection, localization and quantification of voltage and current disturbances are important tasks in monitoring and protection of distribution systems. The concept of discrete wavelet transform for feature extraction of power quality disturbance signals has been incorporated as a powerful tool for detecting and classifying power quality problems. This paper presents the ability of multiresolution signal decomposition technique, by plotting standard deviations of the decomposed signal at different resolution levels, to classify and quantify the power quality disturbance. It has been also shown that the curve obtained by plotting the entropy of the decomposed signal at different levels provides clear information for the detection and quantification of the power quality disturbances.