An islanding surface searching approach based on Floyd-warshall and DFS algorithm

Reasonable islanding strategy is significant for avoiding blackout when the power system suffers from major fault. On the basis of this, this paper analyzes the electrical connection between nodes and proposes a new method of islanding strategy searching based on Floyd-warshall and DFS algorithm. By comparing the degree of electrical coupling relationship between load nodes and generator groups, the problem of islanding strategy searching can be mapped to the partition of the shared nodes. Afterwards, the shared nodes can be divided into proper island by further search which takes the minimum unbalanced power in each island after islanding as the objective function. After the above steps, the optimal islanding strategy can be obtained. The proposed method owns the advantage of low computation complexity and high fitness of operational modes. The effectiveness and rapidity are demonstrated through case studies on IEEE-39 test system and IEEE-118 test system.