Performance evaluation of microgrids in occurrence of intentional islanding

Government incentives to use alternative renewable sources of energy have caused an increase in requests for connections of small generators in distribution networks. The presence of this distributed generation enables its islanded operation, forming microgrids, when there are contingencies in the main grid. Taking into account the Brazilian regulating procedures for distribution networks (PRODIST), the paper evaluates the quality of service during intentional islanding. The paper presents simulation results for the periods of forming the island, operating in islanded mode, and reconnecting the island into the main grid. The simulation results are performed in an actual rural feeder in the Rio de Janeiro State, where the power capacity of two small-hydro generators is able to supply the peak load of the feeder.