A Scalable Multi-Timescale T&D Co-Simulation Framework using HELICS

The power grid is fast changing with the integration of various distributed energy resources (DERs) and it is becoming imperative to model and include these in a correct method. Transmission and Distribution (T &D) co-simulation is an effective tool to accurately consider the DERs and account for the changing power grid for various power system planning and operational studies. We have developed a T&D co-simulation framework with commercial transmission system solvers like PSS/E that can handle largescale transmission networks, and accurate distribution system solver (GridLAB-D) that can model the distribution systems down to the house level and behind-the-meter DERs. PSS/E and GridLAB-D are combined using HELICS environment and are driven using Python to enable multi-timescale T&D co-simulation. This framework is scalable and parallel computing compatible that will enable large-scale system simulations. This framework will enable adoption of T&D co-simulation methodology by the industry and utilities. The scalable multi-timescale T&D co-simulation framework will be instrumental to enable faster integration of DERs by making the various planning and operational studies more accurate.