Study On Multi-objective Of Reconfiguration Of Distribution Network With Distributed Generation

In order to alleviate the problems caused by environmental pollution and increasing power consumption caused by traditional power generation,a large number of distributed power sources(DGs)are connected to the distribution network.The access of DG will affect the network loss,voltage fluctuation and short-circuit capacity of the traditional distribution network.The reconfiguration of the distribution network can effectively reduce network loss,reduce voltage fluctuations and control short-circuit capacity.At the same time,the reconstruction of distribution network involves multiple targets and achieves optimality at the same time.Therefore,it is of great significance to study the reconstruction of multi-target distribution network with DG.Distribution network reconstruction includes an optimized model of reconstruction and an optimization algorithm for solving the optimization model.Firstly,the distribution network model suitable for reconstruction optimization is studied.Based on the relationship between the endpoints,connection nodes and conductive devices in the IEC61970 CIM topology package,the distribution network connection model is established.The mapping model is mapped by the mapping rule.For the distribution network reconstruction diagram,the simplified method of reconstruction diagram is given.On the basis of the distribution network reconstruction diagram,a spanning tree algorithm for generating radial network is proposed,which is used to reconstruct the feasible solution.The improved forward-thinking power flow calculation method is used to calculate the power flow of the distribution network with DG.Secondly,the Pareto optimal concept is used to deal with the multi-objective problem in the optimization model,and the convergence,distribution and diversity of the Pareto optimal solution are proposed.The strategy,through the standard test function,verifies the correctness and effectiveness of the adopted strategy.Based on the above research work,a reconstruction optimization model with minimum network loss,minimum node voltage offset and minimum short circuit capacity as the optimization target to meet the topology constraints and power flow constraints of the distribution network is established.For the switch,the discrete multi-objective particle swarm optimization algorithm is used to solve the reconstruction optimization model,and the reconstruction algorithm program is written in C++ language.Finally,taking the actual distribution network in a certain area as an example,the correctness and effectiveness of the reconstruction model and reconstruction algorithm are verified.The results show that the Pareto optimal solution obtained by the reconstruction algorithm can be used for the reconstruction optimization of the actual distribution network,and the proposed lifting strategy to ensure the Pareto optimal solution performance can make the Pareto optimal solution obtained by the actual distribution network have Better convergence,distribution and diversity;at the same time,DG access can effectively improve system network loss,voltage fluctuations and reduce short circuit capacity.