Damping of Low-Frequency Oscillations in Grid-Forming DFIG Employing the Swing Equation

For a grid-forming (GFM) doubly-fed induction generator (DFIG) that employs a swing equation, low-frequency oscillations may easily manifest, owing to the limited flexibility of tuning a swing equation for active damping. To address this issue, this article develops an active-damping control for the GFM DFIG. The developed control is directly applied in parallel with the conventional swing equation, enabling a straightforward implementation in practice. Concerning the control tuning burden, the control development process restricts the number of control coefficients to just one. Subsequently, theoretical analyses are performed to validate the effectiveness of the proposed control method. Based on a practical DFIG integration system, the developed control has been further validated by the simulation studies in different scenarios.