Frequency-Constrained Robust Unit Commitment Model Considering Virtual Inertia Control of Wind Farms

As the penetration of renewable energy sources (RES) in modern power systems increases, the resulting reduction in inertia and inherent uncertainty pose significant challenges to traditional frequency response strategies. To address these challenges and maintain frequency stability during severe contingencies, this paper presents a frequency-constrained robust unit commitment model that incorporates virtual inertia control (VIC) from wind farms. The model accounts for wind power prediction errors by defining a specific uncertainty set for the real-time equivalent virtual inertia of the wind farms. By integrating primary frequency response with the calculated virtual inertia, a day-ahead scheduling approach is developed under this robust framework. The effectiveness of the enhanced frequency regulation capability of wind farms is demonstrated through application of the proposed model on a modified IEEE 39-Bus test system.