Research on Coordinated Frequency Modulation Control Strategy of Wind-Storage System Based on Virtual Synchronous Generator Technology

In order to enhance and ensure the frequency modulation capability of wind turbines, this paper proposes a coordinated frequency modulation control strategy for wind-storage systems based on Virtual Synchronous Generator (VSG) technology. This approach addresses the high capacity demand and poor economic efficiency associated with traditional energy storage systems that directly compensate for the frequency modulation capability of wind farms. First, a mathematical model of the wind-storage VSG system is established based on its structural framework, and the frequency modulation characteristics of the wind-storage VSG are analyzed. Next, the frequency modulation control methods for the energy storage system VSG are studied according to its mathematical model. Then, considering the output characteristics of both the wind farm and the energy storage system, a coordinated control strategy based on wind turbine inertia release and steady-state support from energy storage is proposed. This strategy optimizes the parallel output control of the wind farm and the energy storage system. Finally, the feasibility of the control strategy is verified through simulation analysis, which demonstrates that it significantly reduces the capacity configuration of the energy storage system while maintaining stable output frequency support, thereby improving the economic efficiency of frequency modulation for the wind farm.