Fault Reconstruction Strategy For Distribution Network Based On Soft Open Point And Considering Islanding Partition

In recent years,with the promulgation of favorable national new energy policies,the penetration rate of distributed power in the distribution network has become higher and higher,and the voltage and power flow distribution of the power distribution system have also changed accordingly.The randomness and nature of renewable energy Intermittent makes the operation control of power distribution system more uncertain.At the same time,with the construction of the smart grid,the topological structure of the active distribution network is more diversified,and the control methods are more flexible and changeable,which provides a means of coping with the opportunities and challenges brought about by the high penetration of distributed power sources.The fault recovery of active distribution network is studied from the perspective of topology adjustment.On the basis of considering the time-varying characteristics of source-storage-load and island division,an improved binary particle swarm optimization algorithm is proposed for active distribution network fault reconstruction,and intelligent soft switch(soft open point,SOP)instead of the traditional contact switch is introduced into the distribution network reconfiguration,which maximizes the power supply recovery of the load during the fault,and enhances the operation stability and risk resistance ability of the distribution system.The main work of the paper is as follows:The steady-state model of SOP is constructed,the working principle and control mode of SOP are analyzed,the SOP model and its operation constraint equation are given,and the operation performance of SOP under normal and fault conditions is simulated on the basis of IEEE33 examples,which verified that it plays a role in isolating faults and controlling power flow and voltage in distribution network.Based on the operating characteristics of intelligent soft switches,an island division model of active distribution network considering photovoltaic time-varying and load operating characteristics is established.The model takes into account the control mode of SOP when a fault occurs,and considers the influence of time-varying distributed power sources and loads of different levels on island operation.Under the cooperation of SOP,energy storage systems and distributed power sources,breadth-first search and depth-first search are used.The method of searching and combining adjusts the operation mode of the distribution network with the main goal of restoring the power supply of important loads first,which improves the utilization rate of distributed power sources and further enhances the operation stability of the distribution system.And the correctness and effectiveness of the model and algorithm are verified on the IEEE33 node calculation example.An improved binary particle swarm optimization algorithm is studied for active distribution network fault restoration and reconfiguration control.First,a distribution network reconfiguration model is established with the reconfiguration objectives of maximizing load restoration and minimizing network loss.Considering On the basis of island division,a discrete binary particle swarm optimization algorithm is introduced for fault reconstruction.This paper improves the activation function and acceleration coefficient in the algorithm,and combines the selective crossover operation in the genetic algorithm with the binary particle swarm optimization algorithm.The convergence and convergence speed of the algorithm are improved,and it is effectively prevented from falling into local optimum.Finally,the effectiveness of the algorithm is verified by an IEEE33 node example,which proves that the algorithm can effectively solve the distribution network reconfiguration problem,and has a faster convergence speed and better calculation efficiency.