Reduced communication based local averaging method for low voltage DC microgrid

DC microgrid consists of distributed sources, energy storages and loads interfaced through power electronic converters. In dc microgrid, maintaining low voltage regulation and proportional load sharing in various load conditions are the main objectives. Various communication based distributed control schemes are proposed in the literature, which have proven to be effective in realizing the aforementioned objectives. However, the existing schemes rely on an all-to-all/full communication topology. This results in a vast and unreliable communication architecture. A reduced communication-based cooperative control strategy is proposed in this paper to attain low voltage regulation and proportional load sharing. The communication topology is fixed and directed such that each converter receives information from at least one other converter. The source converters exchange their current measurements only with their neighbors. Each source converter uses this information to compute the local average current. This local average current is used to adjust the droop gain and voltage shift in the droop characteristic of the source. A small signal model with proposed control strategy for the microgrid is presented. Simulation results illustrate the performance of the microgrid with the proposed control scheme.