With the large-scale grid integration of renewable energy (RE) generation

frequent occurrences of broadband oscillations have been observed in RE plants. RE plants incorporate devices such as static var generators (SVG) besides wind turbines and photovoltaic (PV) generation units.Analytical models and mechanistic understanding remain deficient in characterizing the impact pathways and dominant contributing factors of SVG control modes on broadband oscillations in RE plants. This paper first constructs the small-signal transfer relations of SVG under different control modes (reactive power control mode and AC voltage control mode)

establishes a three-port network model comprising RE generation

SVG

and the power grid. Subsequently

quantitative analysis is conducted to determine the causes of impedance characteristics discrepancies under different SVG control modes and their impacts on system impedance

and the influence patterns of SVG control modes on RE plant oscillations is revealed. Finally

simulation experiments on the impact of different SVG control modes on broadband oscillations in RE stations were conducted based on the MATLAB/Simulink simulation platform

verifying the correctness of the analytical conclusions.