Study on Wideband Oscillation Suppression by Grid-Forming Reactive Power Compensation Using Frequency-Adaptive Damping Control

Wideband oscillations have become an important stability concern in converter-dominated power systems, while conventional reactive compensation devices provide limited damping capability over varying oscillation frequencies. This paper develops a grid-forming reactive power compensation scheme equipped with frequency-adaptive damping control. The proposed controller extracts the oscillatory component from the PCC voltage, estimates the dominant oscillation frequency online, and schedules the damping gain and phase-compensation parameters accordingly. The adaptive damping signal is then incorporated into the voltage-forming control loop without changing the basic voltage-support and reactive-power regulation functions. Comparative simulations are conducted under fixed-frequency and time-varying oscillation scenarios. The results show that the proposed method provides more consistent damping performance than fixed-parameter control and can maintain effective oscillation suppression when the dominant frequency changes over a wide range. The proposed approach offers a simple control solution for enhancing the damping contribution of grid-forming reactive power compensators.