V2G车网互联的双向AC/DC变换器直流阻抗模型及特性分析OA

The control of bidirectional AC/DC converters and the DC output impedance are crucial for the grid connected operation and stability analysis of electric vehicle charging stations.First,the virtual synchronous motor(VSM)control strategy with DC droop link is proposed,and the upper-level power command is used to realize the non-differential regulation for DC voltage of the bidirectional AC/DC converter.Then,a small signal model of the VSM power loop is established to analyze the interaction and influence between active power transmission,active power command and DC voltage.Furthermore,the DC output impedance model of the bidirectional AC/DC converter controlled by the DC droop VSM is established,and the influence of key parameters such as damping and inertia coefficient,DC side capacitance,transmission power,and DC droop coefficient on the DC output impedance is further analyzed in detail.Finally,the simulation result and impedance measurement verify the effectiveness and correctness of DC droop VSM control strategy and the proposed impedance model.