Abstract:

As the penetration rate of electric vehicles increases year by year, the phenomenon of disordered charging and discharging caused by electric vehicle access will affect the stable operation of power grid. Electric vehicle access is considered based on the traditional microgrid model and the microgrid system is studied. The objective function including microgrid operation cost and electric vehicle user charge and discharge cost is established. NSGA-II algorithm based on Levy flight is used to optimize the system scheduling. Considering the randomness and flexibility of electric vehicles, a reasonable orderly charging and discharging scheduling strategy for electric vehicles under different electricity price mechanisms is proposed. An improved NSGA-II algorithm based on Levy flight is proposed. By using Levy flight to generate new subpopulations and merge with the offspring populations of traditional NSGA-II, the diversity of the population can be enhanced, exploration ability can be strengthened, and the probability of falling into local optimum can be reduced. Finally, taking the microgrid system of a certain region as an example, compared with the solution result of NSGA-II standard algorithm, the operating cost of microgrid and the cost of electric vehicle users are significantly reduced, which has high practical value.

Key words: Microgrid, electric vehicle, optimal scheduling, NSGA-II, Levy flight