Island Partition of Distribution Network with Microgrid and Distributed Generation Based on Floyd-Warshall Algorithm

Island operation can ensure the uninterrupted power supply of important loads and improve the system reliability level. This paper studies the islanding problem and the method for calculating the power supply capacity of microgrid is introduced. The islanding model is established based on the equivalent load in isolated islands. Based on the tree-connected graph structure of the distribution network, the island search is performed using the Floyd-Warshall algorithm and the minimum spanning tree method. The concept of island feasible domain is introduced. The depth-first search algorithm is used to determine the feasible island range, which reduces the search space and improves the islanding search efficiency. The islanding model considers the importance of load, power balance, voltage and current constraints, which are in line with the actual project. Finally, an example is used to verify the rationality and effectiveness of the proposed islanding method.