Enhancing the Frequency Control Stability in Large-Scale VPPs with Limited Capacity of Fast-Response Units
摘要
As renewable energy penetration increases, Virtual Power Plants (VPPs) must not only manage energy scheduling but also ensure system security, particularly in response to frequency fluctuations. Existing research focuses on optimizing Primary Frequency Control (PFC) and developing specific control strategies for VPP units. In this study, a dynamic simulation model of a VPP was constructed, and two control systems—Energy Management System (EMS) and Capacity Coordinated Frequency Control (CCFC)—were established and optimized for better control effectiveness. The results demonstrate that the EMS designed for rapid energy storage response is better than traditional methods in responding frequency disturbances caused by rapid power demand changes. Under EMS control, the frequency nadir improved by 17.5%, and the time to reach steady-state was reduced by 77.2% during rapid power increases. Similarly, the nadir improved by 17.1%, and the steady-state time was reduced by 69.5% during power decreases. In addition, the coordinated optimization of EMS and CCFC enhances the VPP’s ability to manage large-scale power fluctuations. The safe power step adaptation range is expanded from 5 MW to 25 MW when the BESS’s dispatchable power is limited. This study highlights the potential of integrated control strategies to significantly enhance the frequency regulation and overall stability of VPPs.