Local DC Distribution System in Presence of RES and Storage Devices: Multiport Converters Application

Modern distribution grids need to satisfy strict standards in terms of voltage quality and continuity. Furthermore, RES should be integrated at different levels in distribution systems, which can lead to non-negligible problems in terms of energy dispatch and protection systems. These considerations contributed to a new interest for direct current in distribution systems. Among different possible solutions, it may be of interest to introduce multiport converters: their centralized control allows to coordinate the various ports in order to maximize voltage quality and continuity. In this paper two types of multiport converters will be considered. For each topology power flow control will be developed to obtain consistent operation in steady state and under heavy load variation or grid connection loss and pole-to-pole fault behavior will be analyzed for the two considered topologies. Criteria to choose between the examined configurations for a specific application will be provided.