Abstract: After the large-scale integration of renewable energy sources such as wind power and photovoltaic power into the grid, the characteristics of power electronic interfaces alter the inertia and damping properties of traditional power systems, leading to broadband oscillation issues that threaten system security and stability. This paper investigates oscillation suppression technologies for renewable energy grid-connected systems, analyzes the oscillation generation mechanism, and focuses on the application methods of virtual synchronous generator technology, additional damping control technology, and coordinated control technology. By establishing a mathematical model of the renewable energy grid-connected system, relevant damping control formulas are derived, and simulation cases are used to validate the technical effectiveness. The results show that additional damping control based on VSG enhances the system damping ratio, while coordinated control strategies can adapt to different operating conditions, providing reliable technical safeguards for oscillation suppression in renewable energy grid-connected systems.