Impedance Modeling and Analysis for Grid-Connected Converter Based on Hybrid Synchronization Control

In recent, hybrid synchronization control (HYBSC) that combines the grid-forming control and the grid-following control is regarded to be able to provide both efficient power control and voltage/frequency support. In this paper, the grid-connected three-phase converter based on HYBSC is studied, and the harmonic linearization method is used to establish the small-signal impedance model, which considers the frequency coupling effects. Then, the validity of the theoretical impedance model is verified by time-domain simulation based on MATLAB/Simulink. Finally, the impedance characteristics of the converter with HYBSC are compared with the converter based on conventional grid-following current control (GFCC).