Islanding algorithm of distribution system with distributed generations based on improved kruskal alogorithm

To improve the system reliability with distributed generations(DGs)under fault conditions, Islanding operation has become an important operation mode. In this paper, a distributed islanding method based on Kruskal algorithm is proposed. By converting the system's structure diagram into connected graph, islanding problem would be changed into minimum spanning tree problem. Set search rules according to islanding principles and constrains, and the islanding scheme can be obtained by searching the connected graph. By checking constrains after each search step, the safe and steady operation of the system can be achieved. Case analysis on typical system shows that the proposed algorithm is effective.