Assessing the Effect of Preventive Islanding on Power Grid Resilience

Cascading faults, caused by extreme weather events or other natural hazards, have been reported to be one of the main mechanism causing widespread blackouts of the power network. A method for preventing the propagation of cascading faults and thus improving power network resilience is intentionally sectionalizing the network into islands. This paper presents a model for simulating cascading faults and evaluates the impact of islanding on island adequacy and network resilience using suitable metrics. The islands are created using two different approaches, a top-down approach based on spectral clustering, and a bottom-up approach. The model is tested and demonstrated in detail on a modified IEEE 30-bus network and the results are quantified using intentional and unintentional load shedding as metrics. The results of the simulations highlight that islanding can effectively prevent cascading faults and thus has a positive effect on network resilience. Results are also provided for the IEEE 57-bus and 118-bus networks to demonstrate the scalability and flexibility of the model.