Nonlinear Large Signal Stability Analysis of Dispatchable Virtual Oscillator Control

Large-signal stability is a crucial aspect of power system planning, mainly concerning the ability of power sources to re-synchronize with each other following a disturbance. This paper delves into an exhaustive examination of the large-signal stability under dispatchable virtual oscillator control (DVOC), a sophisticated grid-forming control paradigm meticulously de-signed to facilitate the seamless integration of renewable energy sources into forthcoming grid infrastructures. Commencing with a detailed characterization of power transfer dynamics between DVOC and the grid, the study proceeds to derive the critical clearing time, serving as a pivotal metric delineating the maximum permissible fault duration before system stability is compromised. Employing both Lyapunov's indirect and direct methods and supported by an innovative nonlinear Lyapunov function, the analysis intricately navigates stability and attraction domains, thereby elucidating the salient parameters governing large-signal stability under DVOC. Rigorous validation of the proposed critical clearing time and Lyapunov function is es-tablished through comprehensive simulations executed within MATLAB/Simulink, affirming their technical robustness and practical applicability across diverse scenarios.