Optimization Strategy for DFIG Rotor Kinetic Energy and Energy Storage Output Using Partitioned Variable Step Size Algorithm

Wind-storage systems are widely used in wind power frequency support, but there is still a lack of optimized coordinated control strategies. This paper proposes a wind-storage coordinated control based on a partitioned variable step-size optimization algorithm. It integrates inertia power support commands into traditional turbine-side MPPT control, with energy storage employing droop control. Throughout different stages of wind-storage frequency regulation, adjustments are made to the turbine-side converter and energy storage-side variable step-size adjustment factors. This determines the output of both the wind turbine inertia and the energy storage battery, leveraging the rotor kinetic energy and coordinated control of energy storage to maximize inertia support while meeting economic requirements. The theoretical analysis is supported by a 2MW doubly-fed induction generator simulation platform, confirming the effectiveness of the proposed control strategy.