Robust event-driven dynamic simulation using power flow

Abstract The power grid is a dynamic system encompassing numerous control devices with varying degrees of time constants, posing a challenge for dynamic simulators to efficiently step through time. We introduce a robust event-driven simulator to mimic dynamic simulation that exploits the inherent temporal sparsity by solving for the quasi-steady state of the grid using frequency-dependent power flow at each time-step. In this methodology, the effect of fast transient control actions is captured within the quasi-steady state while a time-dependent outer loop handles slow transients that dynamically change over time. The event-driven approach offers a fast simulation framework capable of scaling to large systems by taking time-steps based on proceeding events and uses a robust power flow simulator, Simulation with Unified Grid Analyses and Renewables (SUGAR), to solve for the quasi-steady state. We demonstrate the efficacy of this approach by simulating the effects of different control actions including automatic generation control (AGC), automatic voltage (AVR) and over excitation limits on large systems.