Computationally Efficient Dynamic Simulation of Integrated Transmission and Distribution Systems

Dynamic simulation of integrated transmission and distribution (T&D) systems is becoming increasingly useful for the effective control and protection of power grids as the modern power distribution grids with high penetration of distributed energy resources (DERs) show interesting and significant dynamics to consider. The conventional approaches for solving integrated T&D dynamic simulation using off-the-shelf solvers or using Direct Sequential Integration (DSI) methods are slow. Therefore, this work presents a distributed approach to solving dynamic simulation of integrated T&D systems in order to speed up the computation time. This article proposes to use Gauss Jacobi Waveform Relaxation with Windowing based approach that allows solving the dynamics of T&D systems in parallel, which provides significant speed up on the solve time compared to the DSI method. The efficacy of the proposed approach is demonstrated using large-scale T&D systems (more than 10,000 nodes), and the accuracy and performance are compared to the solutions obtained from the DSI method. On large-scale test cases, the proposed approach provides speed up more than four times for solving dynamic simulation compared to the DSI method.