Impedance Modeling and Parameter Influence Analysis of Grid-Connected Inverters with Additional Voltage Feedforward Control

In grid-connected systems where inverters serve as the energy interface, oscillation issues frequently occur. To enhance the anti-interference performance of the inverter, a voltage feedforward link is often introduced into its control structure. However, feedforward control can significantly change the operating characteristics of the inverter, which can impact the stability of the system. This paper employs a multi-harmonic linearization method to construct and validate an impedance model that includes additional voltage feedforward control for grid-connected converters. It further analyzes the effects of additional voltage control on the impedance characteristics and broadband oscillations of grid-connected converters, proposing an optimal parameter design strategy to effectively eliminate negative damping. Finally, experiments utilizing the control hardware in the simulation platform were conducted, with results fully validating the analytical accuracy of this study.