Self-organized Partition of Distribution Networks with Distributed Generations and Soft Open Points

Abstract

Islanding operation relying on distributed generations (DGs) is anticipated to be a promising operational measure for resilience enhancement of distribution networks. In this paper, a self-organized network partition framework for controllable DGs (CDGs) is proposed for the distribution network with DGs and soft open points (SOPs) from a game-theoretic perspective. The labeled numbers of the nodes on paths between every two adjacent CDGs are used as the optimization variables in the partition formation, which can avoid a large number of invalid partition schemes. Two objectives including the weighted recovered load and the power loss are considered, which reflect the goals of maximizing the critical load recovery and minimizing the power loss, respectively. The power loss is determined through the AC power flow calculation using Newton-Raphson method considering the operational characteristics of SOPs. The partition problem is modeled as a discrete bi-objective game, which is further transformed into a continuous game model, and the existence of the Pareto-Nash equilibrium is also proved. A decentralized method is developed to solve the proposed bi-objective game relying on the local communications and a global information discovery scheme, which is more practical after the extreme events. Numerical studies on the IEEE 69-bus distribution system and a 135-bus multi-feeder system are performed to validate the effectiveness of the proposed method. The proposed model is applied in different network topologies, and compared with the centralized optimization models. The robustness of the method to communication failures is analyzed, and the scalability of the proposed model is also validated through testing it in a larger distribution network.