Cascading-driven Intentional Controlled Islanding for Enhancing Power Grid Operational Resilience

Power grids face significant threats from severe disturbances, often triggered by extreme weather, leading to widespread cascading power outages. Although intentional controlled islanding (ICI) is an effective last-resort operational mitigation strategy employed by system operators worldwide to prevent complete cascading blackouts, the impact of large-scale disturbances, particularly weather-induced cascading outages, on when and where to implement the ICI, is neither adequately considered nor reflected in current operational decision-making standards and procedures. This paper proposes a holistic cascading-driven ICI framework that seamlessly integrates advanced weather-related event modelling and cascading risk quantification of high-impact low-probability (HILP) (or tailrisk) events by using a novel ICI based on decision-making mechanism for enhancing the power grid operational resilience. The proposed framework provides a portfolio of mitigation actions proportional to cascading impacts, differentiating between tail-risk events and expected (average) events typically addressed in reliability-oriented studies and current industry practices, while being tailored to both near-real-time operations and short-term operational planning. The proposed framework involves system splitting around black-start units while forming stable and self-sufficient islands, thereby enhancing reliability and resilience. Studies on the IEEE 39-bus and IEEE 118-bus systems demonstrate the effectiveness with a significant improvement in served demand across all simulated initiating events, including up to$N-6$contingencies.