Multi-Area System Frequency Response Modelling Considering VSG-Based Energy Storage

Abstract

With the increasing penetration of renewable energy sources, power systems face challenges in frequency stability due to reduced inertia and uneven frequency regulation capability. This paper proposes an extended system frequency response (SFR) model incorporating virtual synchronous generator (VSG) control with energy storage systems (VSG-SFR model) to improve frequency dynamics. A regional VSG-SFR model is further developed for multi-area systems with non-uniform inertia distribution. Small-signal and frequency-domain analyses are performed, followed by extensive validation via time-domain simulations under various scenarios. Results show that the proposed models closely match detailed simulations, accurately reflect frequency response characteristics, and effectively improve frequency nadir and RoCoF in high renewable environments. Furthermore, the models offer a unified framework for assessing coordinated operation and provide practical insights for optimizing energy storage and enhancing grid resilience in renewable-dominant scenarios.