Control strategy of electric charging station with V2G function based on DC micro-grid

The number and variety of electric vehicles connected to grid continue to grow rapidly, which results in a heavy burden on grid. To solve this problem, the concept of V2G (Vehicle to Grid) that electric vehicles could act as a new power source for grid was proposed. With distributed renewable energy developing fast recent years, charging EVs is a good way to use it. The DC micro-grid program being conducted at the Xiamen University (China) consists of a 150kW peak photovoltaic system. A unique charging station has been proposed designed on the basis of the DC micro-grid, featuring three-way energy flow among the power grid, PV modules and electric vehicles. The paper proposes a charging station based on DC micro-grid which also can provide V2G service. The control strategy of converters is investigated. Finally, simulation based on MATLAB is built to validate the availability and effectiveness of the proposed system and control strategy.