A Distributed Control Method With Seamless Hot Swap Capability for Generic DC Microgrids

This article proposes a distributed secondary control method for droop-controlled dc microgrid (MG) systems with ring or mesh configurations. The control method achieves accurate current sharing and improved load voltage regulation than the conventional droop method by using the bus voltage information of any bus of the dc MG system. The secondary controllers are implemented locally at each converter, thus ensuring a distributed control. The proposed method requires communication of only one signal per communication link and it needs less number of communication links than the state-of-the-art distributed secondary control methods. The method also offers a seamless hot swap capability of a converter as there is no interdependence between the secondary controllers of the converters. The effectiveness of the proposed method is validated using switching simulations and hardware-based experiments on different configurations of dc MG systems.