A Novel Distributed Secondary Control Strategy Applied to Hybrid AC/DC Microgrids

In this paper, a distributed secondary control strategy for hybrid ac/dc-microgrids is proposed. The control strategy restores the variables modified by the primary control loop, i.e. voltage on the dc-side and voltage amplitude and frequency of the ac-side, to their nominal values while maintaining a good power-sharing capability between ac- and dc-units. A distributed communication network among the generation units is needed for the proper performance of the control strategy, however, a high bandwidth communication network is not needed to ensure a good behaviour of the proposed control scheme. The effectiveness of the control scheme is validated through simulation of a 9.0kW hybrid ac/dc-microgrid.