Research On Island Division And Multi-fault Repair Strategy Of Active Distribution Network

With the continuous access of distributed power sources and the increasing controllable load,this paper focuses on distributed power sources with volatility such as wind and light,and isolates and faults of distribution networks with distributed power sources.The restoration strategy is studied to improve the power supply security of the power system and improve the energy utilization rate.The main research work carried out in this paper is as follows:Firstly,this paper systematically introduces the theory,development status and significance of the research on the island division and multi-fault repair strategy of distribution network with distributed power supply.The characteristics of various distributed power sources are analyzed in detail.After the power supply is connected to the distribution network,the influence of the distributed power supply on the fault current and fault location of the distribution power supply lays a foundation for the research on the island division and multi-fault repair strategy of the distributed power supply.Then,in order to solve the problem of power supply recovery after the failure of the distribution network with distributed power supply,an islanding method based on bubbling algorithm is applied.First,the distribution network is converted into an undirected connection graph;then,by giving the weights of the nodes of the undirected connection graph,the bubble set algorithm is used to search for the set of nodes that satisfy the condition;finally,the load nodes outside the set are Switch off.The simulation results show that the bubbling algorithm can maintain the integrity of the power distribution system to the greatest extent.After the fault is removed,only the load switch can be switched to restore the system power supply.The proposed islanding method is applicable not only to the radial network but also to the radial network.Ring network.Finally,in a distribution network with distributed power supplies,the output power of the distributed power source is random and the power required by the user is constantly changing.When there are multiple faults in the distribution network,the fault repair time is longer,and the distributed power supply may be insufficient in a certain period of time.In order to ensure the recovery of power for as many users as possible in the non-light loss area after the fault,this paper combines the short time scale optimization scheduling method to establish an active distribution network based on Multi-Agent System(MAS),taking into account different regions and time.In the paper,the parameters of the distribution network are different.In this paper,the power loss recovery area is the largest and the number of switching times is the upper level target.The power failure recovery is performed under different recovery periods and different switching times in each non-faulty power loss zone.The maximum value is the premise that the total power supply is the lowest target,and the optical storage and DG participate in the joint optimization dynamic repair model.An island path optimization method is proposed,which can quickly find the optimal recovery path in each period of non-faulty power loss zone.