Research On Charging Optimization Strategy Of Electric Vehicle Considering Spatial-temporal Distribution Characteristics

In recent years,environmental pollution has become increasingly severe.As a new energy vehicle,electric vehicles have great advantages in alleviating energy shortages and reducing environmental pollution.However,with the wide application of electric vehicles,users’ disorderly charging behavior will interfere with distribution.Therefore,in order to promote the coordinated development of electric vehicles and the distribution network,it is necessary to analyze the impact of electric vehicle charging on the distribution network and formulate corresponding strategies to guide the orderly charging of electric vehicles.The research content of this article is summarized as follows.Firstly it analyzes the impact of electric vehicle charging load characteristics,vehicle charging methods and user behaviors on the charging load of electric vehicles.Monte Carlo method is used to establish the charging load of electric private cars,electric buses,electric taxis and electric official vehicles.The model compares the influence of electric private cars,electric buses,electric taxis and electric official vehicles on the load curve of the distribution network under the conditions of disorderly charging and time-of-use electricity price guidance.Secondly aiming at the problems of heavy computation and high communication difficulty in centralized charging control of electric vehicles,a hierarchical optimization strategy for charging electric vehicles in residential quarters is proposed,which includes two stages: day-ahead scheduling and real-time optimization.In the day-ahead scheduling stage,with the goal of minimizing the variance of distribution network load and minimizing the charging cost of users,an improved sparrow algorithm is adopted to solve the optimal time distribution of charging load of electric vehicles.In the real-time optimization stage,the load expectation curve is taken as the optimization result of the previous scheduling stage,and the charging probability of electric vehicles in each period is calculated.Taking the distribution network of a residential district as an example,the effectiveness of the proposed strategy is verified.Finally aiming at the coordination problem between the power generation side and the electric vehicle charging load,a space-time double-layer optimization strategy for the electric vehicle charging load is proposed.The upper layer takes into account the output of wind and photovoltaic energy,and the minimum operating cost of the generation side and the minimum charging cost on the user side are taken as The goal is to optimize the power output of the generator set in each period and the time distribution of electric vehicle charging load;the lower level considers the distribution of power flow in the distribution network,and optimizes the spatial distribution of electric vehicle charging load with the goal of minimizing the total power loss of the distribution network;On the power system simulation model based on 10 generator sets and IEEE33 nodes,the effectiveness of the proposed strategy is verified.This paper has carried out related research work from two perspectives of the power generation side and the user side.The coordination problem between the power generation side and electric vehicle charging is considered,the time and space distribution of electric vehicle charging load is optimized,and the load fluctuation of the distribution network and the charging cost of users are effectively reduced,and the economic benefits of the power generation side are improved.