Research Information System
in: Advances in Power System Modelling, Control and Stability Analysis (2nd Edition), Federico Milano, Editor, Institution of Electrical Engineers , London, pp.663-694, 2022
Recently, attempts have been made to understand and analyze the dynamic interactions between the power grids and the inverter-based resources (IBR) such as wind and solar photovoltaic (PV) parks. These adverse incidents that mainly stem from the controller interactions can lead to unwanted oscillations in sub- or super-synchronous frequency ranges, and thus jeopardize the reliable operation of power systems. To address such stability analysis issues, frequency-dependent impedance scanning techniques based on small-signal perturbations have been developed. This chapter deals with detailed explanation of different scanning methods that can be employed for predicting the stability issues and characterizing the sub- or super-synchronous oscillations. Implementation, computational burden, accuracy, and stability criteria for different scanning methods are also discussed. Stability assessment based on the scanning methods is investigated in three practical benchmark systems that involve full size converter (FSC) and doubly-fed induction generator (DFIG) wind parks. The positive-sequence, the dq and the αβ scans are applied to stable and unstable cases in each benchmark and the results are verified by the electromagnetic transient (EMT) simulations.