(1. School of Electric Power, South China University of Technology, Guangzhou 510640, China; 2. Guangdong Key Laboratory of Clean Energy Technology(South China University of Technology), Guangzhou 511458, China)

With an increase of microgrids in a certain area, multi-microgrids(MMGs)systems with different sequence structures are gradually formed. Hence the significance of developing a rational and reliable microsource-load-storage restoration strategy is important. In view of the emerging hybrid MMGs with a single-phase/three-phase architecture, a microsource-load-storage recovery sequence optimization method is proposed with the three-phase unbalance constraint and the stability margin of MMGs taken into account. Firstly, the operation margin and stability margin of MMGs are put forward to determine the restoration sequence of the microsources, loads and energy storage systems. The concepts of operation margin and stability margin of MMGs are put forward, and the microsource-load-storage restoration events are abstracted as the vertices of the connected undirected graph. Then, the optimum microsource-load-storage restoration sequence is found through the generalized minimum spanning tree algorithm based on the improved Prim algorithm. Finally, the flow chart of vertex cluster formation considering the minimum weight between clusters is proposed. Simulation results are presented to verify the effectiveness and feasibility of the proposed strategy. This work is supported by National High Technology Research and Development Program of China(863 Program)(No. 2014AA052001).