Quantification and Classification of Short-term Instability Voltage Deviations

As power systems evolve from synchronous to inverter-based generation, short-term voltage stability evaluation plays an increasingly important role. Voltage perturbations become faster and highly variable, exposing systems to much larger risks of cascading faults. Therefore, assessing the severity and origin of potential voltage deviations becomes a critical step in risk-based vulnerability analysis of modern power systems. In this article, a novel approach that evaluates rapid post-fault voltage deviations for both online and offline short-term instability quantification and classification is investigated. The findings indicate that the approach is intuitive and effective in automatically determining the severity and type of instability. Such an output enables grid operators to anticipate and prioritize potential high-risk events and act with suitable preventive and/or corrective actions. Finally, the article provides future research directions that deal with the open grid resilience challenges. Particularly, the challenges related to post-disturbance dynamic system strength evaluation are addressed.