Research On Service Restoration Strategy Of Distribution System With Distributed Generations

Distribution system is an important part in power system which connects power production and consumer. Along with the continual development of the national economy and the unceasing enhancement of the People’s lives, the people set the more and more request to the reliability, security and efficiency of the distribution system. When the distribution system with distributed generations have faults, it is important to ensure the important load power supply and restore the supply of the field without faults quickly.Based on the analysis of the characteristic of distribution system with distributed generations and power flow calculation method, the service restoration strategy after the fault is presented. The service restoration strategy is divided into two stages, divided island and distribution network reconfiguration based on the improved binary particle swarm optimization.In the first stage of island divided, this paper presents a method based on graph theory. The distributed generations with nearby important load form the islands to ensure the important load power supply, in order to improve the reliability of the system. This method make the distributed generations as the root node, through DG and the installation point of the synchronizing parallel devices form the initial island. Base on initial island, combine the breadth first search and the priority fusion important load method forming a single DG island scheme, according to a single DG island scheme form the eventually island scheme.The second stage of the distribution network reconfiguration is a large-scale, multi-restrictions, nonlinear combinatorial optimization problem. According to characteristics of the standard binary particle swarm algorithm is easy to fall into local optimal result, this paper optimize the parameters of the algorithm and combine the differential evolution operator which have the strong function of maintenance the population diversity.this method is the improved binary particle swarm optimization. We use the method to restore the supply of the field without faults quickly. Through the IEEE33nodes, IEEE69nodes distribution test system and a practical grid test system, we know the model and the algorithm are validated. The results show that the algorithm can effectively solve the service restoration problem of distribution system with distributed generations.