Analisys of the robustness and sensitivity of distribution systems for optimal allocation of monitors in face of Short Duration Voltage Variations.

Abstract

In order to better understand, solve and equalize the costs associated with the financial losses resulting from a poor Power Quality (PQ), several studies and analysis have been applied to define measures and establish procedures that will improve the quality of the service and product offered by utilities distribution of electricity.In this context, the doctoral project to be presented, proposed by Thais Reggina Kempner, will be on defining a methodology for the assessment and prediction of indices that reflect the robustness and sensitivity of Distribution Systems (DS) in face of Short Duration Voltage Variations (SDVVs), i.e. voltage sags, voltage wells and interruptions.It is known that most SDVVs in a given distribution network, among other situations, are directly related to the occurrence of short-circuits. In three-phase systems, a fault condition may involve one or more phases and ground, or may occur only between phases. However, regardless of the type of occurrence, it is not predictable, characterizing randomness to the phenomena associated with SDVVs.In this scenario, the project will be based on the method of Fault Position (FP) seeking to characterize, for each type of short-circuit, the voltage magnitude for all DS bus bar, denoting the influence and propagation of SDVVs around the network as a whole. This information will be crucial for establishing the compatibility between the levels of sensitivity of various types of equipment connected to the system and to better assess the performance (robustness) of DS points in the supply of electricity. It is believed that by applying the methodology to be developed, it will be possible to analyze the DS as a whole, bringing technical and financial advantages when compared to usual and arising expenses from long and complex monitoring campaigns that would be necessary to address this theme.As a result of a successful approach it is intended to validate the analytical method to be proposed by comparing the results with those from computer simulations in real time using the RTDS (Real Time Digital Simulator). Featuring from the distribution system running in real time via the RTDS it is possible, for example, to engage meters and certain interest loads, checking settings and responses in face of operating conditions, providing in this way, results very close to a real DS.By the experience obtained in this subject during her masters, and by continuing this line of research, it seems reasonable to conjecture that the candidate for the project will be able to go deeper in this subject during her doctorate, allowing the indication and assessment of indexes that will reflect the real consequences of SDVVs on distribution systems.The topic being researched is directly associated with the PQ, which is linked to one of the lines in 2010/01690-2 FAPESP thematic project, in which the professor Dr. Mario Oleskovicz (advisor for this project) is in the position of "main researcher".