Generalized Short-Circuit Ratio Based Distributed Real-Time Stability Assessment of Renewable Power Systems

Since the small-signal stability (SS) of a renewable energy system is time-varying in response to operational scenario changes, it is significant to monitor the critical stability situations in real time so that timely preventative actions can be taken to avoid potential SS risks. To this end, a distributed real-time SS assessment (SSA) approach is developed based on the grid strength metric of generalized short-circuit ratio (gSCR). Specifically, a structure-preserving representation of the gSCR is formulated for conservative estimation in a multi-agent environment. On this basis, a fully distributed power method is designed to monitor the time-varying gSCR for real-time SSA. Simulation results illustrate the effectiveness and efficiency of the proposed approach under various scenarios.