| This thesis focuses on the combined microgrid and studies the economic operation of the combined microgrid.In addition,an orderly charging and discharging model of electric vehicles is established,and the charging and discharging mechanism of electric vehicles is optimized.The main research content and results of this thesis are as follows:(1)The operating characteristics of three types of distributed power sources are analyzed,and a mathematical model about the output power of distributed power sources is established.The Monte Carlo method is used to obtain the specific travel time and travel time distribution of electric vehicle users,which establishes the foundation for the study of charging and discharging of electric vehicles.(2)In this thesis,electric vehicles will be integrated into the combined microgrid as a distributed power source,and the real-time electricity prices will be set by price-based demand response model for reduce the operating cost of the combined microgrid.For solving the operation model of the combined microgrid,this thesis will take the operating cost of the combined microgrid and the lowest charged cost of electric vehicles as the objective functions.The results of the calculation example show that by adopting the real-time electricity price mechanism and controlling the reverse power supply of electric vehicles,the operating cost of the combined microgrid and the charged cost of electric vehicles are significantly reduced.(3)In order to reduce the charging failure rate and lack of charge of electric vehicles,an orderly charging and discharging model of electric vehicles considering the charging failure is established.The discharge margin and charging urgency are used to control the orderly charging and discharging of electric vehicles.Taking the lowest charged failure rate and the least lack of charge as the objective function,an orderly charging and discharging plan is developed for electric vehicles.The result of the calculation examples shows that the orderly charing and diacharging model of electric vehicles can effectively reduce the charged fail rate and lack of charge of electric vehicles.(4)In order to improve the accuracy of the results obtained when solving the model,this thesis uses the gravity search algorithm to optimize the particle swarm algorithm,and proposes a hybrid particle swarm and gravity search algorithm based on linearly decreasing weights.Simulations verify the effectiveness of the optimized algorithm in solving the problem of combined microgrid optimal dispatching and orderly charging and dischaiging of electrical vehicles. |
