Analysis of Power Quality Variations in Electrical Distribution System with Renewable Energy Sources

Abstract

The increasing u se of Power Electronics along with Distributed Generation Systems (DGs) has been playing a predominant role in the efficient operation of Electric Power Systems. Thus, studies regarding identification and classification of Power Quality (PQ) events have been a subject of recent interest for researchers from the view point of initiating suitable control actions in DGs for achieving improved performance. This requires carrying out a detailed analysis of the various characteristics of real time electrical signals through a set of signal processing techniques . PQ distortions due to environmental factors, such as change in wind speed and solar irradiations are considered in this work. Signal features are extracted for various voltage sag/swell signals using S-Transform, while signal-classification is done by Least Square Support Vector Machine (LS-SVM) technique. A 17-bus test system is modeled using the open source software, Open Distribution System Simulator (OpenDSS). Smart converter control is realized with inputs received from signal classifier, so as to initiate proper grid-support functions. Controlled actions realized are Volt-VAr and Volt-Watt functions. The performance of the control functions is tested for varying levels of solar and wind penetrations. The efficacy of the results is imminent based on control actions being in line with the set reference.