Study On Island Division And Service Restoration Reconfiguration For Distribution Network With Distributed Generation

Along with the increasing share of distributed power in the power market,it has had many impacts on the intelligent operation of the distribution network,economy and failure recovery strategies.In order to meet the challenges under the new situation,research on the fault recovery strategy of distribution network with DG is beneficial to improve the operational stability and power supply reliability of the distribution network,improve the power supply quality of the distribution network,and help build a strong smart grid..The island division and fault recovery reconstruction of the distribution network is a multi-objective hybrid solution problem.According to the characteristics of the distribution network with distributed power supply and the operating characteristics of the distributed power supply,the fault recovery of the distribution network is divided into power distribution.Network reconfiguration and island operation are used to study and process,and a more realistic recovery model is established,which comprehensively considers the load priority level,restores the total power load and restores the active power after power supply.Firstly,this paper discusses the related methods of topology analysis,combined with the structural characteristics of the distribution network,through comparative analysis of the contact relationship between nodes and branches in each method,selects the breadth-first search method to search and realize the dynamic identification of the distribution network structure change.A radial constraint method for distribution network based on undirected graph is designed.Combined with the topology characteristics of the distribution network,through comparative analysis of various distribution network power flow calculation methods,the improved forward-forward generation power flow calculation method is applied to the power flow calculation,and the distributed power supply is processed accordingly to make it suitable for Trend calculation.For the distribution network after fault isolation,the fault recovery of the distribution network is divided into two parts: distribution network reconstruction and island operation.In the parting of the island,the related principles and principles are introduced firstly,then the root tree model of the islanding division of the distribution network with DG and the objective function and constraints of the islanding considering multi-purpose are established.Combining the tree root model and the path selection rule,the breadth-first search method is selected for island division.In the reconfiguration part of the distribution network,a comprehensive model for recovering as much load as possible and considering line loss under the condition of multiple constraints is established,and the binary particle swarm optimization algorithm is used to solve the problem.The comprehensive analysis is carried out with specific examples.The test results show that the application of this method can not only restore the power supply of the distribution network,but also reduce the active loss and ensure the reliable and economical operation of the distribution system.