Hybrid AC/DC-OPF ADMM model for TSO coordination with multiple DSOs in Flexibility Market

Unlocking potential from flexibility assets is an effective way to address power grid challenges. Proper coordination between transmission and distribution system operators (TSO and DSOs) is key to achieving this goal. This paper presents a framework based on optimal power flow (OPF) for coordination of flexibility exchange between TSO and multiple DSOs. As a basis, the Hybrid AC/DC-OPF model, where the transmission grid represents DC OPF model and the distribution grid represents SOC-AC OPF model, was used. To establish TSO coordination with multiple DSOs, the Hybrid AC/DC-OPF model was extended with Alternating Direction Method of Multipliers. The test case, which includes three distribution grids connected to one transmission grid, was created based on a Pandapower grid and a synthetic grid generated by Ding0 package. The test case proves the ability of the model to solve scenario-based and multi-period problems when TSO-DSOs coordination is established. Furthermore, the analysis shows the economic benefits and reduced volume of load shed and active losses in the distribution grids when flexibility assets are used.