Transient Stability Enhancement of Virtual Synchronous Generators Based on Additional Frequency Control

Virtual synchronous generators (VSGs) are susceptible to transient instability, especially under large disturbances without equilibrium points (EPs). This article proposes an additional frequency control to restore EPs and ensure transient stability. In this control, the damping effect is enhanced to improve the transient behavior, and the additional potential energy is introduced to restore EPs after detecting the transient instability characteristics of VSGs. Compared with previous stabilizing methods, the proposed method can address transient stability issues both with and without EPs, and it does not rely on any grid information. Simulations and experiments validate the effectiveness of this method.