Power Oscillation Suppression Strategy for Synchronous Generator and Virtual Synchronous Generator Parallel System

In islanded microgrids, power oscillations often occur in system where virtual synchronous generator (VSG)-controlled inverters operate alongside synchronous generator (SG), which can trigger overcurrent protection. To address this problem, this paper first establishes small-signal and state-space models of the SG-VSG parallel system and analyzes the impact of parameter variations on system stability. Subsequently, an improved VSG control method is proposed based on the concept of power frequency-domain decomposition, which utilizes high-frequency component of VSG output power to suppress active power oscillations and enhance system stability. Finally, simulations verify the feasibility of the proposed strategy.