Research Of Coordination Strategy And Communication Between V2G Charging Station And Grid

The technology of electric vehilces intergratie to the grid is the inevitable trend ofthe development of smart grid. In the future, electric vehilces can not only be used asdistributed energy source and energy storage devices and smoothing system for newenergy source to intergrate to the grid, but also can be used as peak regulatoring andvellay filling energy source. In fact, the essence of electric vehicle is a load, when amassive and uncontrolled of electric vehicles access to the grid, it will cause apressure of peak on peak to the grid and make the power supply cannot meet thedemand of the load, which will lead an electrical accident. Electric vehicle as a“double edged sword” will not only bring hope and advantages to the smart grid, butalso bring challenges to the power grid. However, it is able to solve the problemsbetween advantages and challenges.To achieve the goal that making full use of theadvantages the electric vehicles provided and minimizing the trouble, we need tosolve two problems, the first is the problem of charging and feeding managementstratege, and the second is the communication between V2G Charging Station andPower Dispatching System.Power battery is the key component limit the electric vehicles to interact with thegrid, there are many electric characteristics of its own. To test the charge anddischarge characteristics of lead-acid battery, some experiments were taken, andcombining the feature models, the characteristics of constant voltage, constant current,constant power and the State of Charge are analyzed. Based on the literatures, thedaily-load characteristics of power grid and daily statistical characteristics of theelectric vehicles are analyzed, and by an ordered control strategy, the peek regulatorand the vellay filling problem can be solved.Based on the experiment and analysis, a peak regulator and vellay filling strategy,which is using the real-time SOC weight to distribute the electric power, is proposed.To feed the remaining energy back to the grid during the peak load period, setting anenergy limit of an electric vehicle and using the SOC weight to dispatch the realtimepower based on the grid dispatched power. Similarly，to obtain the energy from thegrid during the valley filling period, the same way using the SOC weight to dispatchthe realtime power based on the grid dispatched power is taken. According tostatistics, using the proposed strategy can quickly make most electric cars to beenergy balanced during the process of peak regulator and valley filling. To solve the problem of communication between the V2G Changing Station andthe Adjacent Level Power Grid Dispatching System, a method of using the IEC61850standard to design V2G Changing Station management system is proposed. By usingthe object oriented information abstracted modelling method and the ACSI abstractedcommunication service interface, the information model and the key communicationservice for V2G Changing Station management system were designed, respectively.Experiments results show that the communication system based on the propsedmethod can realize the seamless communication and interoperability between V2GChanging Station management system and the Adjacent Level Power GridDispatching System.To verify the effectiveness of the peak regulator and valley filling strategy basedon SOC real-time weight, simulation and test experiments were taken, and to realizethe key service of the ACSI, the programme of the V2G Charging Stationmanagement system was deviloped.