| Large-scale popularization and development of new energy-powered vehicles represented by electric vehicles is one of the important measures to solve the fossil energy crisis and environmental pollution problems.There is a positive correlation between the total electric vehicle charging load scale and the electric vehicle ownership.With the continuous increase of electric vehicle load,its impact on the safe and stable operation of the power grid is gradually expanding.Therefore,establish a medium and long-term charging load prediction model for electric vehicles,and evaluate the impact of the scale development of electric vehicles and the evolution of charging load on the power grid.The main work of the paper is as follows:Based on the open source data of vehicle driving track in a domestic city,the effective travel rules of users are mined.Firstly,through data preprocessing,information format conversion and inverse geocoding,the original data is transformed into valid reproduced data.Next,statistical analysis of the trip feature quantities in the regeneration data is carried out to obtain the transition probability,driving distance and driving speed of different types of activity trips.Finally,a trip probability model is established by fitting the statistical feature quantity data through a Gaussian mixture model.It lays a foundation for the subsequent calculation of electric vehicle charging load.Based on the user travel law of data mining,and considering the seasonal difference of electric vehicle charging load,mid-to-long-term load prediction model of electric vehicle is established.Firstly,based on the travel law model,combined with the charging characteristics of electric vehicles,the calculation of electric vehicle charging load is realized.Then,based on the Bass model,the estimation of the model parameters takes into account the influence of domestic historical data and future market development element,and a Bass correction model considering the influence of multiple factors is established to predict the number of electric vehicles in the next few years.Finally,combined with the electric vehicle charging calculation model and the Bass correction model,the prediction time is extended from the short-term to the medium and long-term,and the medium-and long-term charging load prediction of the electric vehicle in different seasons is realized.Mid-to-long-term load forecasting model of electric vehicles,the acceptance capacity of electric vehicles in the distribution network is analyzed,and the impact of the development scale of electric vehicles in the medium and long term and the evolution of charging load on the distribution network is evaluated.Focusing on the influence of electric vehicle charging load on the load capacity and voltage level of the distribution network,respectively,from the peak-to-valley difference of the overall load of the regional power grid,the node voltage level of the local medium and low voltage feeders,and the load of the distribution transformer connected to the functional area.Three aspects of capacity are used to evaluate the ability of the distribution network to accept the charging load of electric vehicles.Finally,the system package design is carried out for the evaluation of the electric vehicle acceptance capacity of the distribution network,which is convenient for the replication of the method or the transplantation of the code,and provides a technical reference for the subsequent development work. |
