Turbine-Efficiency-Weighted Frequency Regulation Energy Extraction Strategy for Wind Farms

Large-scale wind power integration will negatively affect the power system’s inertia level and the anti-interference capability and stability of frequency and voltage characteristics. Optimizing the coordinated frequency control strategy among wind turbines under the influence of efficiency characteristics is key to reducing frequency regulation energy losses and improving the wind farm’s frequency regulation capability and stability. This paper proposes an adaptive frequency regulation energy extraction strategy under wind farm de-loading conditions. First, based on a control method combining rotor overspeed and pitch regulation, a priority-based de-loading relationship for turbine clusters in the rotating coordinate system is established, considering the efficiency differences between turbines operating in the maximum power point tracking (MPPT)zones and the constant power zones. Second, for turbines in medium-low wind speed zones using rotor overspeed de-loading, the rotor speed margin after pitch regulation is fully utilized to propose a combined pitch and overspeed frequency regulation control method for turbines in high wind speed zones. Field-measured data verification shows significant improvements compared to conventional strategies in terms of total frequency regulation energy, reduced frequent turbine adjustments, and pitch response performance.