Reconfiguration Of Distribution Network With Distributed Power Geeration

The distribution network reconstruction technology can optimize the topology of the distribution network by changing the opening and closing states of the section switches and tie switches in the distribution network,improve the voltage quality and power supply reliability of the distribution network,and achieve balanced load,The purpose of eliminating network overload.As distributed generation(DG)is increasingly connected to the distribution network,the power flow and short-circuit current characteristics of the distribution network have undergone great changes.The traditional distribution network reconstruction method is no longer applicable to the distribution network containing distributed power sources.Therefore,the research on the distribution network containing distributed power sources has important theoretical and practical value.In this thesis,on the basis of summarizing the reconstruction mathematical model,optimization algorithm,multi-objective processing technology,etc,a multi-objective reconstruction optimization algorithm for distributed power generation is proposed.Firstly,the connection model,connection diagram,and basic reconstruction diagram of the distribution network are established on the basis of graph theory and IEC61970-301,and the simplification strategy is further used to obtain a reconstruction diagram suitable for reconstruction on the basis of the basic reconstruction diagram.Taking an actual distribution network in a certain place as an example,it illustrates the generation process from the actual distribution network to the basic reconstruction diagram.The adoption of simplified strategies has significantly reduced the network scale;then,the radial network generation method is used to generate the “closedloop design,open-loop design”.The “loop operation” network expression method uses IEEE33 nodes and the actual distribution network as an example to verify the correctness of the algorithm and ensure the radial expression of the network during the optimization process;The processing and weak-ring network processing are studied,the correction coefficient and reactive power adjustment are introduced when processing the PV node,the injection current method is used when processing the weak-ring network,and the method is verified on the IEEE33 node model.The calculation example shows,The method adopted is simple to deal with PV nodes,has good convergence,and can handle multiple PV nodes at the same time.The processing of weak-ring networks has fast convergence speed and can handle different weak ring points;finally,the Pareto optimal solution set is introduced Concept to deal with multi-objective problems,and on the basis of binary particle swarm optimization algorithm,adding multiple groups,hierarchical evolution of inertial weights,and particle mutation strategy to achieve the improvement of multi-objective particle swarm optimization algorithm.Take the classic test function as an example,the verification shows,The method adopted improves the distribution,diversity and convergence of understanding to a certain extent.On the basis of the above research work,an objective function with the smallest network loss,the smallest node voltage offset and the smallest number of switching operations is established.The optimization algorithm program for the reconfiguration of the distribution network with distributed power is used to solve the reconfiguration problem.Finally,taking the actual distribution network in a certain area as an example,the algorithm proposed in the thesis is verified,and the objective function value before and after reconstruction is compared,and the optimization algorithm of the distribution network reconstruction with distributed generation proposed in the thesis has reached the purpose of optimizing the distribution network is to optimize the relevant variables during the operation of the distribution network,and the proposed method is feasible.