Análise de Impacto de Conexão de Microgeração Distribuída em Redes Desbalanceadas

Abstract

With the growing penetration of distributed generation (DG) in distribution systems, studies into its impact on network operating limits are becoming increasingly necessary. To quantify the permissiveness of a network to the connection of DG, the concept of hosting capacity (HC) has been defined as the maximum energy that can be injected into the network without its operational limits being exceeded. Different studies have been proposed to analyze the impact of connecting new generators, such as simplified methods based on combinations of lower loads and higher generation, and stochastic analyses. However, these are generally too conservative and/or computationally expensive. Using voltage sensitivity matrices provides a good approximation of the system’s behavior. However, analyses involving three-phase sensitivities in unbalanced networks are still little explored. This paper therefore seeks to evaluate the use of the sensitivity matrix in two three-phase, unbalanced test systems to analyze the impact of connecting DG on voltage. The discretization-aggregation method is also used to take into account the uncertainties in the demand and generation curves obtained from real system data. An assessment of the limits of using this type of sensitivity is also discussed. The results show that, for power injections on the order of microgeneration, the sensitivity matrix provides good estimates of voltage increase.