Droop-Based Two-Layer Cooperation for Multiple DC Microgrid Clusters

IFAC-PapersOnLine, vol. 53, pp. 12924–12929

Abstract

Enabling energy exchange among multiple dc microgrids (MGs) and adjusting the current outputs of all converters proportional to their power capacities can significantly improve power supply reliability as well as effectively avoid overloaded or uncertainty. By dividing all converters within each dc MG cluster into the leader-converters and follower-converters according to their physical cluster topology structure, the leader and follower control layers are respectively formulated. Then a droop-based two-layer cooperative strategy is developed, under which the weighted average voltage of all converters can be regulated to their rated references, meanwhile, the accurate current sharing can be simultaneously realized not only within each dc MG but also among multiple dc MG clusters. All controllers are fully distributed and can be applied in all sparse two-layer cyber networks, control time constant related sufficient conditions are also derived to ensure the whole system stability. The effectiveness of the results are verified through different cases in MATLAB/SimPowerSystems.

Authors 2

1. Xiaoqing Lu corresponding

   Wuhan University

   Affiliation as printed

   School of Electrical Engineering and Automation, Wuhan University, Wuhan 430072, China

2. Jingang Lai corresponding Aachen E.ON Energy Research Center

   RWTH Aachen University

   Affiliation as printed

   E.ON Energy Research Center, RWTH Aachen University, Aachen 52074, Germany