Voltage Characteristics of Three-Port Integrated Grid-Forming Converter System

Large-scale grid integration of renewable energy systems (RESs) poses a challenge to the voltage stability of power systems. Although grid-forming (GFM) control technology has been widely used to improve the active voltage support capability of RESs, most existing studies have focused on the voltage stability at the point of common coupling (PCC), and insufficient attention has been paid to the system voltage model. To this end, this paper focuses on the three-port integrated (TPI) GFM converter, establishes an equivalent circuit model of the system voltage response, conducts mathematical derivation and theoretical analysis accordingly, and reveals the key influencing factors of the voltage at the PCC in depth. On this basis, this paper further discusses the voltage stabilization control strategy for these factors. Finally, the influencing factors and control strategies are fully verified through the MATLAB/SIMULINK simulation platform, which provides a solution to the voltage support problem of new energy access to the grid.