Data-Driven Damping Ratio Estimation and Stability Assessment for VSC-Based Power Systems

Power systems based on voltage-sourced converters (VSCs) enable large-scale integration of renewable and alternative energy resources. However, the high-depth penetration of VSCs gives rise to small-signal stability challenges due to their control interactions and the variations of system operating points. In the technical literature, small-signal stability of VSC-based power grids is typically assessed using transfer function or statespace models that are linearized around one operating point. These models often require internal system information and/or
measurements that are not available in practice, and they need to be updated when the operating point changes. To tackle these issues and expedite stability assessment of VSC-based grids, a data-driven approach that predicts the system damping ratio is proposed. This approach (i) does not require internal system information, (ii) only needs a reduced set of measurements, and (iii) is applicable across varying operating points. The effectiveness and accuracy of the proposed data-driven method is verified based on time-domain simulation studies.