Real-Time EMT Simulation of Islands Synchronization During Black Start

Following a complete or partial blackout event, black start is essential to the power system restoration process. Black start involves restarting generator units and restoring power without relying on the external electric grid. To mitigate the risk of unplanned blackouts, power utility companies are proactively enhancing their preparedness measures. This preparation entails developing real-time electromagnetic transient (EMT) studies for islands' re-energizing and synchronization, conducting training exercises, and investing in essential infrastructure to ensure an effective recovery process. However, the building and initialization of real-time EMT model can be extremely time-consuming. This paper introduces the reusable, modular development of large-scale real-time EMT models of Dominion Energy's transmission system, and a data pipeline that facilitates the integration of real-time data from EMS to effectively initialize the EMT model and improve model accuracy. The efficacy of the above procedure is verified and exemplified through a two-island transmission system model, with which a series of islands synchronization studies are performed. The studies aim to examine critical parameters, including synchronization angles, voltage, and frequency difference, to ensure reliable operation after synchronization. Potentially, this work could assist system operators in synchro-check relay settings, decision-making during black start, and training. This work could also provide an outline for future large-scale transmission system model expansion.