Research On The Electric Vehicles Participating Frequency Regulation Of The Microgrid Based On V2G Technique

With the growth of global economy, world's demand of energy is becoming higher and higher. At the same time, the burning of fossil fuels has been aggravating environmental issues such as globle warming, energy crisis and fuel pollution. So electric vehicle technology is attracting more and more worldwide attentions. Electric vehicles are the most promising class of new energy vehicles as well as the main strategic orientation of new energy vehicle development. The grid-connected large-scale of electric vehicles bring new opportunities and challenges to the safe and stable operation of power system. The Vehicle to Grid technology(V2G) is regarded as a controllable load, which can act as a distributed energy storage unit and can be used as a distributed power supply, to mitigate the intermittency and uncertainty of the renewable energy generation as well as to provide regulation and spinning reserve ancillary services effectively. On the basis of existing research, this paper carried out further research.According to statistics, most of the cars are idle during the day, taking good use of the electric power idle in the electric vehicles battery is advantageous for the optimization of power grid operation. V2G technology development is the basic condition of friendly interaction between the electric vehicles and grid. Firstly, this paper introduces the concept of V2G technology and composition of the V2G system, then analyzes the advantages of the electric vehicles participating in grid peak peel, auxiliary service, disturbance and so on. According to the different control strategy, three kinds of connected models are presented, which include decentralized V2G model, centralized V2G model and V2G model based on the microgrid. Electric vehicle battery model and probability of initial capacity of the battery are introduced, to lay theoretical basis for the following analysis.Secondly, in this paper, a frequency model including electric vehicles and island is studied. Frequency modulation characteristic of the diesel generator and electric vehicles are analyzes respectively, then based on the characteristic a control strategy is proposed. A frequency model including electric vehicles and island is set up. Finally to verify the effectiveness of the proposed control strategy, simulations for electric vehicles participating a island are performed in the Matlab/Simulink program, the simulation results indicate that the electric vehicles participating in the island frequency control is feasible.Finally, how to make PEV provision profitable in the marketplace is an essential subject for the mass deployment and growth of the PEV industry. Based on analysis of the cost-benefit of the PEV's frequency regulation, an optimization model is developed to maximize aggregator's profits, which includes the battery state of charge and customer charging demand. Particle swarm optimization is used to solve the model, Simulation examples show that the optimal planning model and its solutions are effective.