| With the increasingly serious fossil energy crisis,more and more renewable energy sources are connected to the distribution network(DN).Due to the randomness and uncertainty of renewable energy,after the renewable energy sources are integrated into the DN,there will be many problems in the DN,such as power fluctuation,overvoltage,and frequency imbalance,which have great impacts on the economical and reliable operation of the power grid.In order to solve the problems of power fluctuation and voltage over-limit caused by renewable energy sources,energy storage(ES)technology is widely used in the system.More and more ES devices are integrated into the power grid to stabilize power fluctuations and improve voltage profile.At the same time,with the development of battery technology,electric vehicle(EV)have developed rapidly.Renewable energy sources,ES devices and EVs,after integrating into the DN,form a multi-characteristic active system.The integration has a significant impact on the power distribution and the voltage stability of the grid and puts higher requirements on the economic and reliability.A collaborative optimization model of the active DN is required.This thesis will optimize the active DN operation through network reconfiguration and charge/discharge optimal schedule of ES and EVs.Firstly,according to the characteristics of distributed generation,ES and EV in active DN,the model of each component of active DN is established.Secondly,an optimal charging/discharging scheduling model considering battery operation,distribution network operation cost,and charge/discharge cost is established to optimize the charging/discharging schedule of energy storage and electric vehicle.Then,a network reconfiguration model that comprehensively considers renewable energy sources,ES and EV is established,so that the distribution network operation is more economical and reliable.Further,based on the network reconfiguration model of active DN and the optimal scheduling model of ES and EV,the cooperative optimal operation model of active DN is established to optimize the operation of the active DN.Aiming at the model,an improved PSO algorithm is proposed.It can find the optimal solution more quickly and effectively.Finally,the IEEE standard system is used to analyze the effectiveness and feasibility of the proposed theories. |
