Cascadings in large power systems: Benchmarking static vs. time domain simulation

Cascading stems from the interaction between control, protection, and defense systems, and it is affected by uncertainties in system models and external factors. An evaluation of cascading thus requires the collection of exhaustive and reliable data. Uncertainties could be accounted for by applying Monte Carlo techniques to time domain simulation, but a large computational effort would be implied. Static cascading simulation approaches are more suitable to carry out probabilistic cascading evaluation. However, the issue of consistency between static and dynamic simulation outcome arises. The present paper reports results from benchmarking quasi-static, cascading simulation used in the operational risk assessment tool PRACTICE against a time domain simulator. The comparison, performed on the model of a realistic power system, highlights the consistency of the quasi-static approach with time domain simulations at least in the early stages of cascading.