Parallel-in-Time Solution of Power Systems with Scheduled Events

This work presents a time-parallel approach for solving power grid problems with scheduled events (e.g., a square pulse applied to a bus). The multigrid reduction in time (MGRIT) method, implemented in the XBraid code, is used to nonintrusively add time parallelism to GridDyn, an existing open-source power grid simulation tool. The approach extends standard practices for sequential time stepping and scheduled events to the time-parallel setting and then explores temporal refinement. The paper concludes with a parallel validation showing speedups of around 50× for the WECC 179 bus system. Scalability with respect to scheduled events is examined by applying a one second long square pulse to bus 143 every 2 seconds.