Multi-objective Distribution Network Reconfiguration Considering Time Variation Of Load And DG

With the rapid growth of global energy demand,Distributed generation(DG)is more and more popular because of its clean and environment-friendly characteristics,and its penetration rate in the power grid is increasing gradually,when it is connected to the power grid,it will affect the operation characteristics of the existing power grid,and the load demand will fluctuate with time.Therefore,this paper takes into account both the load and the time-varying characteristics of distributed generation,and does a deeper research on the process of distribution network reconfiguration.Firstly,in the power flow calculation of external power supply,the generation model of distributed power supply and the corresponding node type are analyzed,and the IEEE33 system is taken as an example,the improved back-stepping algorithm is used to analyze the effects of DG grid-connected schemes on system voltage and network loss,which lays a foundation for static and dynamic reconfiguration of DG grid-connected.Secondly,in the aspect of static reconfiguration,this paper establishes the static reconfiguration model of distribution network in DG access scenario.In order to improve the optimization efficiency of the Algorithm and eliminate the infeasible solutions,a "minimum loop" coding method is proposed,combining with the improved genetic ant colony algorithm proposed in this paper,taking IEEE33 and PG&E69 Distribution Systems as examples,the two systems under various DG grid-connected scenarios are simulated respectively,the influence of DG on distribution system under different access schemes is analyzed,and the applicability and effectiveness of the proposed algorithm are verified.Finally,in the aspect of dynamic reconfiguration,considering the load and DG change in the actual distribution network,this paper selects the loss load balance and voltage offset index in the actual operation of distribution network to construct a multi-objective function,the Weight Coefficient of voltage offset and load balance degree takes the leading position when dealing with the weight of each index,which ensures the safety and stability in the system reconfiguration.In the reconfiguration time division,a two-step time division method is proposed to confirm the optimal reconfiguration scheme,and the improved genetic algorithm proposed in this paper is used to solve the multi-objective and multi-state reconfiguration problem which is tested and analyzed by IEEE33 system,the no-DG access scenario and the multi-type DG access scenario are considered to verify the correctness and effectiveness of the proposed method.