Energies, Vol. 12, Pages 255: A Multi-Layer Coordinated Control Scheme to Improve the Operation Friendliness of Grid-Connected Multiple Microgrids (Energies)

Multiple microgrids (MMGs) are clusters of interconnected microgrids that have great potential for integrating a large number of distributed renewable energies (DREs). The grid-connected control scheme is important for the exploration of the MMGs’ operation potential. In this paper, a multi-layer coordinated control scheme for DC interconnected MMGs is proposed to optimize their operation and improve their operation friendliness. An adaptive droop control method is designed for the DC connection interfaces of the MMGs to adaptively manage the power exchange among the sub-microgrids. Meanwhile, the strategy of power fluctuation suppression is developed for the hybrid energy storage system (HESS) in the MMGs. The coordination among the sub-microgrids and the HESS is then clarified by the proposed control scheme to optimize the AC tie-line power and make the MMGs a highly coordinated collective. A case study is performed in PSCAD/EMTDC based on the demonstration project in Guangxi, China. The results show that the proposed multi-layer coordinated control scheme realizes the coordinated operation of the MMGs, fully exploits the complementarity of the MMGs, and improves the operation friendliness among the sub-microgrids and the utility grid. Thus the integration and utilization of a large number of DREs is enhanced.