Research On Application And Business Model Of Electric Vehicle Virtual Energy Storage In Power Grid

With the increasingly prominent environmental problems,electric vehicles have developed rapidly,but a large number of electric vehicles charging disorderly is not conducive to the stability of the power grid.However,with the increase of the number of electric vehicles,there are a large number of long-term idle electric vehicles.If these idle electric vehicles are used as energy storage units to participate in the auxiliary services of the power system,it will not only give full play to the energy storage function of the electric vehicle power battery,improve the stability of the power grid,but also bring certain economic benefits to the power grid and the owners.In this paper,the application.and business model of electric vehicle virtual energy storage in power grid are studied,and the optimal control method of household load microgrid system considering the state of health of batteries is proposed.The economy of electric vehicle virtual energy storage under different business operation modes is compared and analyzed.The main contents of this paper are as follows:Firstly,the available capacity of electric vehiclevirtual energy storage is studied.Based on the driving data of different working types,the number of electric vehicles in each area is obtained through the probability density function of parking time.Considering the charging and discharging modes,the parameters of batteries and charging and discharging limits of different types of electric vehicles,the available power capacity and energy capacity of different locations are calculated.Secondly,the state of health of lithium-ion batteries is studied.The wavelet packet decomposition method is used to filter the experimental data of lithium-ion batteries and the relationship between capacity attenuation and internal resistance of lithium-ion batteries is analyzed.The capacity attenuation model of lithium-ion battery based on improved semi empirical model is established,and the parameters of the model is identified by genetic algorithm(GA)and particle swarm optimization algorithm(PSO).The validity and correctness of the model are verified by the measured data.Then,the application of electric vehicle virtual energy storage in household load microgrid system is studied,and the optimal control method of household load microgrid system considering the state of health of the battery is proposed.Taking the minimum cost of electricity,the minimum capacity attenuation of the battery and the mimimum emission of carbon dioxide as the objective functions,a multi-objective optimization model of microgrid system including grid,photovoltaic,electric vehicle and household load is established fully considering the constraints of electric vehicle charging and discharging,power and available capacity.NSGAIII algorithm is used to obtain the optimal Pareto solution set of the model,and TOPSIS algorithm is used to obtain the optimal solution,which realizes the optimal control of electric vehicle virtual energy storage in household load microgrid system.Finally,the business operation mode of electric vehicle virtual energy storage is studied,and the mathematical models of three investment and financing modes such as third-party investment,power grid investment and electric vehicle owner investment.The economy of virtual energy storage of electric vehicles under three investment and financing modes is analyzed through simulation examples.