Variable Coefficient Droop Control Strategy for Optimal Participation of Wind Farm in Primary Frequency Regulation Considering Wake Superposition Effect

Abstract

When traditional wind farm participates in frequency regulation, the wake effect on the operating conditions of wind turbines is usually ignored, which makes the upstream wind turbines capture too much wind energy and the wind speed attenuation of downstream wind turbine is too large. So the wind farm fails to maximize the output power, and the contribution of the wind farm to participate in frequency regulation will reduce. In order to fully tap the potential of wind farms participating in system frequency regulation under actual conditions, this paper adopts the Jensen model to establish a wind farm power optimization model considering the superposition of wake effects under actual operating conditions. The interior point method is used to coordinate the axial induction factors of each wind turbine to optimize the output of the wind farm. Furthermore, since the fixed droop coefficient cannot well reflect the ability of wind turbines participating in frequency regulation under different wind speeds, a variable coefficient droop control strategy is proposed for wind farm to participate in the primary frequency regulation optimally. Simulation studies are carried out to demonstrate the effectiveness of the proposed strategy.