Virtual synchronous motor based control scheme of electric vehicle charger

Fast charger is a key grid-interface component for the electric vehicle application. In this paper, a utility-friendly solution for the fast charger of electric vehicle application was presented based on the virtual synchronous motor (VSM) control scheme. In the proposed solution, the converter for the fast charger involves an AC/DC stage and a DC/DC stage. The AC/DC stage is an active rectifier integrated VSM control scheme to ensure the dc-link 600V and some advanced features. Then, the converter in DC/DC stage can buck the DC 600 V voltage to DC 48 V and feed the electric vehicle loads. Thanks to the presented solution, some advanced features and benefits can be confirmed. On one hand, the employed VSM control scheme in the AC/DC converter can guarantee the low total harmonic distortion of grid-tied current and support the utility with necessary inertia and damping in abnormal utility voltage and line-frequency conditions. On the other hand, the isolated DC/DC converter is also well controlled to perform fast and constant power charging of electric vehicle loads. The detailed control strategies of the solution were proposed, and their feasibilities and validations were verified by the simulated results using PSCAD/EMTDC and the experimental results on a 50 kW prototype.