This paper aims to describe the main results of a research and development project for allowing the analysis of impacts due to the connection of distributed generation (DG) units to a distribution network and synergies with the expansion planning. The computational implementation has included innovative modules for optimum allocation of DG units, evaluation of system average RMS frequency index (SARFI) for a specific voltage sag magnitude with or without DG units in the network as well as analysis of the impact of a large number of small photovoltaic (PVs) panels. The impact of PV micro-grids is taken into account using the foreseen seasonal and daily variations of sunlight for calculating the generated energy. Since the model allows an integrated representation of low, medium and high voltage networks, the impacts of the DG units can be analysed in any part of the system under study with a single processing. The software has a full graphics interface with integrated maps for helping the planning activities.

This paper presents a methodology that defines the most suitable configurations to allocate reclosers in power distribution networks. The methodology is composed by two stages. At the first stage, optimal configurations to install reclosers in each feeder are established, considering the improvement promoted in continuity indexes. Each configuration corresponds to a previously fixed number of reclosers and indicates the positions where the devices should be installed. So, through this stage, a list of possible optimal configurations is determined for each feeder. At the second stage a global optimization is carried out, in order to define which configuration should be considered in each feeder from a whole power distribution system, in order to maximize the improvement in terms of continuity and considering the total number of devices available. The developments presented are the initial part of a R&D project in progress with CEMIG-D, a power distribution company from Brazil.

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This paper proposes a methodology to identify new opportunities for distributed generation (DG) installations, based on consumer process characteristics and utility network needs. The main objective is to postpone investments in reinforcements using distributed generation in places where it is possible to use cogeneration with surplus capacity. The main costs and benefits are investigated and considered in order to compare the available alternatives.

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