Research On Planning And Optimal Regulation Of Soft Open Point In Active Distribution Network

With the growing penetration level of distributed generation(DG)in the distribution network,the complexity of power flow control continuously increases,which poses huge challenges to the distribution network in terms of planning and operation.soft open point(SOP)is a new type of controllable power transmission device installed in the distribution network to replace the traditional contact switch.Compared with conventional switches,its capabilities in power flow regulation and optimization are more flexible,which can greatly improve the safety and flexibility of distribution network operation control.To this end,this paper focuses on the research of SOP planning and optimization control technology from the perspective of power flow optimization and power quality improvement in the distribution network.The main research contents are as follows:First of all,the distributed generation technology and its impact on the distribution network are introduced.Then,based on the Matpower,a toolkit for power flow calculation and optimization,the influence of distributed power on the power quality of distribution network is analyzed.Secondly,in view of the high computational complexity of the traditional cone optimization model,a circuit equivalent model of multi-port SOP is proposed.This model is compared with the numerical model based on cone optimization to optimize the power flow of the distribution network,which verifies the accuracy of the equivalent model,and also proves that the equivalent model is simple and easy to expand.Then,on the basis of the model research,further research on the regulation ability of SOP in the distribution network was carried out.The results show that the multi-port SOP has the advantages of wide power flow optimization range and strong power control capability compared with the two-port SOP,which has the same number of converters.Finally,for the interactive relationship between SOP planning and distribution network operation optimization,a SOP planning method considering dynamic optimal power flow is proposed.The objective of upper-level planning model is to minimize the annual comprehensive cost,and the objective of lower-level optimization model based on dynamic optimal power flow is to reduce the voltage deviation and net loss in distribution network.An improved hybrid optimization algorithm is used to slove this planning model,and the best planning scheme of SOP is obtained.The results of the simulation show that SOP can effectively solve the problem of voltage overrun caused by DG,and reduce system losses.Moreover,reasonable SOP planning has more significant effect on the improvement of distribution network operation.In addition,by comparing with the traditional genetic algorithm and particle swarm optimization algorithm,the advantages of the proposed algorithm in terms of convergence and fastness are verified.