The Planning Research Of Distributed Generation And Charging Station In Distribution Network

With the increasingly prominent of traditional fossil energy crisis and environmental pollution problems,distributed generation(DG)and electric vehicle has attracted worldwide application due to its resource saving and environmental friendliness.However,large-scale DG and charging station access to the distribution network will have a profound impact on the system's economic operation,power quality and reliability.At the same time,the rapid development of DG and electric vehicle also can not be separated from the scientific and rational planning of the distribution network.In this context,how to coordinate optimization of intermittent DG and charging stations,do a good job on the optimal allocation of DG and charging stations in the distribution networks has great significance for the promotion of electric vehicles,the improvement of consumptive level for DG,increase the utilization of clean energy and the enhancement to the adaptability of distribution network.Based on this,the main work of this thesis are listed as follows:(1)Above all,this paper introduces the definition and classification of DG and EV,and its influence on the operation and planning of the distribution system.Then considering the uncertainty of intermittent DG and load,the K-means clustering algorithm is used to reduce the scene data of the wind speed,light intensity to improve the computational efficiency of model solution and the reduction accuracy.(2)Based on the uncertainty of intermittent DG and load,the model of location and sizing planning with DG and energy storage device is established which considers the time series complementary characteristics of the load,the DG output and the energy storage device.This model can achieve the purpose of optimizing the configuration of DG and energy storage devices at the same time.A simulation example is given to validate that the proposed model and the solution method can effectively increase the accessing capacity of intermittent DG and improve the economy of planning scheme.(3)Considering the characteristic of the random charging behavior of electric vehicles,in order to obtain the time series characteristic curve of charging load,a Monte Carlo stochastic simulation method is proposed to predict the charging load of electric vehicles.Then,based on the charging demand forecasting,taking the profit maximization of the charging station investors as the objective function,the model of location and capacity planning for the electric vehicle charging station is constructed which introduces into the low carbon efficiency index of electric vehicle.The theory and example verify the planning model and solving algorithm can effectively reduce the comprehensive cost and network loss,and improve the overall voltage level of the system.(4)From the perspective of comprehensive coordination planning for distribution network,this papers takes the system annual comprehensive cost,network loss cost and voltage index as sub-objective functions,and constructs the multi-objective comprehensive optimization model of intermediate DG and electric vehicle charging station in distribution network.In order to change the multi-objective function into a single objective function,the analytic hierarchy process(AHP)is used to determine the weights of each sub objective.A concrete example is given to validate the proposed comprehensive planning method can effectively increase the accessing capacity of intermittent DG,educe the network loss,improve the system voltage improvement index,optimize the operation mode of the system,and obtain a more economic planning scheme.In this paper,the intermittent DG and electric vehicle charging station planning in distribution network is studied,which can promote the application of electric vehicles,improve the permeability of DG,optimize the operation of the system and enhance the adaptability of the distribution network,and has certain theoretical guidance meaning and the engineering application value.