Capacity configuration of energy storage for wind farm primary frequency regulation support

Abstract

With the increasing penetration of wind power in modern power systems, primary frequency regulation (PFR) capability has become a mandatory requirement for grid integration. Drawing on the PFR mechanisms of conventional thermal power plants, this paper proposes control strategies for wind farms, specifically including virtual inertia control and droop control. The associated power and energy requirements are analyzed and quantified. It is determined that an energy capacity equivalent to 10% of the wind farm's rated power sustained for 12 min (0.2 h) is sufficient to fulfill typical PFR tasks. Furthermore, three typical frequency regulation energy sources—rotor kinetic energy, reserved standby power, and lithium-ion battery energy storage—are comprehensively compared. The analysis identifies lithium-ion batteries as the most economical solution for PFR energy provision. On this basis, a novel PFR strategy for wind farms with centralized lithium-ion battery energy storage is proposed, and its feasibility and effectiveness are validated through MATLAB/Simulink simulations. The simulation results demonstrate that the proposed strategy achieves superior frequency regulation performance compared to conventional thermal power plants. Moreover, it effectively eliminates the secondary frequency drop problem inherent in conventional virtual inertia control, thereby ensuring stable and reliable PFR support for the power system.