Modeling and control of a V2G charging station based on synchronverter technology

This paper proposes an idea for modeling and control of a V2G charging station (CS) for electric vehicles (EVs) by using synchronverter technology. First, the architecture of the CS is introduced. Then, a T-S fuzzy controller is designed to decide the reference real power of the synchronverter by considering the grid frequency. Due to the inner frequency- and voltage-drooping mechanisms of the synchronverter, the input and output real and reactive power of the CS will be automatically adjusted on the basis of the reference value according to the degree of deviation from the nominal value of the grid frequency and voltage. To ensure the safety of this operation, an adaptive frequency droop coefficient mechanism is designed to adapt the change of the total energy storage of a CS unit by changing the slope of the P-f control characteristic of the synchronverter. The performance of the CS with the proposed control strategy is investigated with EVs of different battery states, different users' sets and under different grid status. Simulation results demonstrate that the proposed strategy can not only effectively perform controlled charging/discharging of each single electric vehicle inside the CS, but also improve the performance of the electricity grid in terms of efficiency, stability and reliability.