Multi-Stage Virtual Angular Frequency Control of Wind-Storage Generation System for Frequency Warning Requirements

Evaluating the system's frequency regulation requirements using frequency security constraints and achieving rapid frequency response through coordinated wind-storage control are crucial for ensuring the stable operation of power systems with high penetration of renewable power generation. In this paper, a virtual angular frequency dynamic response model of the wind-storage generation system is established. Based on the model, the extremum time of the system's angular frequency response is calculated, and its key influencing factors are analyzed. Secondly, a method for dividing the system's angular frequency regulation range into three stages—extremum arrival, wind-storage conversion, and steady-state deviation recovery—is proposed according to the frequency regulation requirements and characteristics. To meet the security indicators of inertia support and primary frequency regulation (PFR) of wind-storage generation systems, a novel coordinated multi-stage virtual angular frequency control strategy is proposed, in which the virtual inertia of the wind turbine is prioritised, the inertia support of the energy storage device is coordinated, and the wind turbine and energy storage device participate in PFR. Finally, a wind-storage power generation system is built on the hardware-in-the-loop platform to verify that the proposed control strategy is conducive to clarifying the coordinated support functions and ensuring system frequency security requirements.