Research On Service Restoration Of Distribution Network With Distributed Generations

When permanent faults occur in distribution network,how to restore the power supply of important loads quickly and as much as possible is the main task of service restoration.Reasonable cooperation of island partition and distribution network reconfiguration can effectively reduce the blackout area and improve the reliability of power supply.How to establish an effective mathematical model of service restoration is still a hot research topic in the field of distribution network service restoration.In service restoration,the intelligent algorithm with stochastic search characteristics shows better adaptability in solving the problem,guarantees the optimization speed and quality,and has good convergence characteristics.Therefore,this thesis deeply studies the complex distribution network service restoration problem with Distribution Generation,improves the Artificial Bee Colony Algorithm and applies it to the distribution network service restoration problem with DG,so as to achieve the most effective optimization effect.The purpose of restoring blackout load to a large extent.Firstly,the current situation of service restoration is analyzed.Several popular intelligent algorithms and their combination algorithms are summarized in this thesis.Their advantages and disadvantages are also discussed.The application of intelligent algorithms in service restoration of distribution networks with distributed power sources is analyzed.The development trend of distribution network service restoration with distributed generation is prospected.The definition,application field,characteristics and classification of DG are described in detail.Several common DG access modes and equivalent models are listed.The impact of DG access on service restoration is analyzed.The forward and backward substitution method is used for power flow calculation of DG-containing distribution network.Secondly,the artificial bee colony algorithm is deeply studied,including the structure of the algorithm and the behavior of various bees.The basic steps of the optimization of the ABC algorithm are given,and the shortcomings of the algorithm and the direction of improvement are analyzed.An multi-strategy artificial bee colony algorithm is proposed to improve the artificial bee colony algorithm.This thesis defines the swarm search strategy and tracking strategy of multi-strategy artificial bee colony algorithm,defines the leading bee cross search strategy,the swarm perception radius and the algorithm search cut-off conditions,and puts forward the principle of selecting the parameters of multi-strategy artificial bee colony algorithm.The basic steps of multi-strategy artificial bee colony algorithm optimization are formulated,and the optimization performance of multi-strategy artificial bee colony algorithm is simulated and analyzed by three test functions.Finally,a DG islanding partition and integrated service restoration reconfiguration model of distribution network are established,and the steps and flow charts of islanding partition and integrated service restoration of complex distribution network with DG are formulated.The model is validated by simulating the IEEE-3 3-node distribution system with DG and the PG&E-69-node distribution system.The results show that the proposed model can be applied to the complex distribution network with DG.After service restoration based on multi-strategy artificial bee colony algorithm,the power supply can be restored to the maximum extent in the non-fault blackout area of distribution network,and the algorithm embodies a strong optimization performance,which proves the correctness and rationality of the calculation results of this method.