Two-degree-of-freedom admittance-type droop control for plug-and-play DC microgrid

For DC microgrids, the “plug and play” capability is one of the most desired functionalities to formulate a fully flexible and scalable system. The “plug and play” operation will put twofold requirements on the control of power sources: on the one hand, they shall share the load properly; on the other hand, the system stability shall be ensured. In this paper, a two degree-of-freedom admittance-type droop control method is proposed to fulfill the requirements of the “plug and play” operation. In the proposed method, both conventional proportional power sharing function and virtual inertia injection capability are included to provide an integrated decentralized solution to ensure proper power sharing and system stability, and therefore being helpful to achieve “plug and play” DC microgrid.