Adaptive Virtual Synchronous Generator Control Scheme for Performance Improvement of Grid-Forming Inverters

Abstract

This paper proposes an adaptive virtual synchronous generator (AVSG) control strategy for three-phase grid-forming (GFM) inverters to enhance the stability and dynamic performance under power disturbances. Unlike conventional methods that use frequency deviation to adjust the VSG inertia and damping coefficients, the proposed approach employs active power variation as the adaptation input. In frequency-based methods, sudden power variations can cause rapid frequency fluctuations and transient spikes, leading to inaccurate or overly aggressive parameter tuning. To overcome this issue, the proposed strategy enables smoother and more reliable adjustment of inertia and damping coefficients, which play a key role in achieving an appropriate rate of change in frequency (RoCoF) and frequency nadir. To further support systematic parameter tuning and dynamic analysis, a small-signal model of the VSG control-based voltage source inverter (VSI) is developed. The proposed method is validated using both simulation studies and hardware-in-the-loop (HIL) experiments, demonstrating enhanced transient response, improved damping, and robust frequency regulation under sudden power variation conditions.