TY  - EJOU
AU  - Zhi, Qing 
AU  - Guan, Jin 
AU  - Zhang, Ruopeng 
AU  - Wu, Lixia 
AU  - Zhang, Shuhui 
AU  - Xue, Xinyu 
AU  - Wen, Caifeng 
AU  - Zhao, Yunlong 

TI  - SOC-Constrained Virtual Inertia Control of Hybrid Energy Storage Systems for Frequency Stability Enhancement
T2  - Energy Engineering

PY  - 
VL  - 
IS  - 
SN  - 1546-0118

AB  - With the increasing integration of renewable energy sources, grid frequency stability has become a major concern, placing higher demands on the dynamic response capabilities of frequency regulation resources. Energy storage systems, with fast response and bidirectional regulation capabilities, demonstrate significant value in frequency control. To address insufficient regulation of the state of charge (SOC) in existing methods, this study proposes a novel frequency regulation control approach for grid-side standalone energy storage stations. The system integrates a supercapacitor with a lithium-ion battery, allocates power hierarchically through low-pass filtering, and implements a virtual synchronous generator (VSG) control mechanism on the grid-connected side to enhance system inertia support. Furthermore, the mapping between charging/discharging coefficients and SOC is refined and embedded into an adaptive virtual inertia control framework, enabling coordinated SOC regulation and enhancing system dynamic performance. Simulation studies are performed using MATLAB/Simulink. The results show that the method significantly improves frequency response, enables more balanced power sharing in hybrid energy storage systems, and mitigates overcharging and over-discharging, thereby enhancing overall operational safety.
KW  - Independent energy storage power station; virtual synchronous generator; hybrid energy storage system; virtual inertia support

DO  - 10.32604/ee.2026.082562