Modeling of Grid-Forming Inverter Control for V2G Operation of EV Charging System

Increasing generation from inverter-based resources (IBRs), especially solar PV and wind energy, significantly challenges the stability of the utility grid due to their inherent low inertia. Predominantly, these IBRs employ grid-following (GFL) inverters, which merely track the frequency and voltage usually measured at the point of common coupling (PCC). To enhance the stability of IBR-dominated power systems, this article presents a nested-loop grid-forming (GFM) control strategy for electric vehicle (EV) charging systems, which facilitates grid-supporting vehicle-to-grid (GsV2G) operations. The proposed GFM control scheme employs P-f droop control for an inductance-dominated grid network by incorporating cascaded current and voltage loop control. The model's performance is verified under various abnormal conditions, including major load disturbances, unsymmetrical faults, and grid outages, thereby justifying the enhanced stability and reliability of the grid network. The model is validated using the MATLAB/Simulink platform.