Short-Term Active Power Reduction in DFIG-Based Wind Farms for Improving First-Swing Stability in Power Systems

In this paper, a short-term active power curtailment (ST-APC) strategy for doubly fed induction generator (DFIG) wind farms is proposed to enhance first-swing rotor angle stability under fault disturbances. While wind power is a clean renewable resource that is widely deployed, its large-scale integration heightens concerns about transient stability. After analysing DFIG operating principles, this study advocates for using short-horizon active power control to mitigate the adverse stability impacts of wind farms. Using the Western System Coordinating Council (WSCC) three-machine nine-bus test system, the effectiveness of the ST-APC strategy across diverse operating conditions is verified. Simulation results show that, following a fault, modulating the DFIG’s active output effectively suppresses the first swing, postpones loss of synchronism, and increases the critical clearing time (CCT). The scheme yields notable benefits regarding improvements in overall stability, reductions in the frequency nadir, and acceleration of frequency recovery. Sensitivity analyses further examine the effects of activation time, control duration, and curtailment depth on CCT and offer tuning recommendations. The findings indicate that the proposed strategy is practical and adaptable, making it suitable for power systems with high wind power penetration.