Research On Multi-fault Recovery Of Distribution Network Considering Island Partition

In recent years,more and more distributed power sources are connected to the power grid such as wind power and photovoltaic.The formation of isolated islands from distributed power sources and loads have become an important form of fault recovery in distribution networks.However,the fluctuation of distributed power output and the time-varying load bring a great challenge to the fault recovery of distribution network.In order to give full play to the potential of distributed power supply and improve the reliability of islanding operation,it is necessary to establish a reasonable and effective scheme of islanding division.Due to the large and complex distribution network structure,the possibility of multiple faults is even greater,which will lead to major power outages,resulting in many production departments being paralyzed by power outages,thus affecting the normal operation of the society.Therefore,it is very important to establish a fast and effective fault recovery strategy.First,this paper analyzes the research status of islanding division in distribution network with distributed power supply and multi-fault recovery considering emergency electric vehicles.In this paper,the algorithm of depth first search is described based on the basic principle of graph and tree.The power flow calculation method of distribution network with distributed power supply is introduced.Finally,the principle of bacterial colony chemotaxis algorithm is introduced,which lays a theoretical foundation for the follow-up research.Then,considering the fluctuation of wind power photovoltaic and the time variation of load,the islanding partition strategy during the fault period is established.First,the primary island is formed by determining the maximum power supply area of the distributed power supply.Then,the primary island is modified by scene to form the secondary island.In the process of secondary island correction,the optimal dispatching of electricity and the coordination of controllable load are taken into account in the process of secondary island correction.Finally,through the power flow test of secondary islands,the optimal scheme of island division is obtained.Lastly,in this paper,a multi-fault recovery model with emergency electric vehicle is established to consider the time-varying loss weight of power outage and load type.Optimization of emergency electric vehicle access point based on minimum loss of power loss of all loads and minimum dispatching time of emergency electric vehicle during fault period.The discrete bacterial colony chemotaxis algorithm and depth first search algorithm are used to find the optimal solution model.Optimal emergency electric vehicle access point are obtained.