TSO-DSO Operational Planning Coordination Through “$l_1-$Proximal” Surrogate Lagrangian Relaxation

The proliferation of distributed energy resources (DERs), located at the Distribution System Operator (DSO) level, bring new opportunities as well challenges to operations within grid, specifically, when it comes interaction with Transmission (TSO). To enable interoperability, while ensuring higher flexibility and cost-efficiency, DSOs TSO need be efficiently coordinated. Difficulties behind creating such TSO-DSO coordination include combinatorial nature operational planning problem involved transmission level nonlinearity AC power flow both systems. These considerations significantly increase complexity even under deterministic setting. In this paper, a is considered novel decomposition approach developed. Within method, decomposed into DSO subproblems, which are coordinated by updating Lagrangian multipliers. nonlinearities caused constraints resolved through dynamic linearization guaranteeing feasibility “ $l_1-$ proximal” terms. Numerical results based on 118-bus system up 32 34-bus systems indicate that method overcomes computational difficulties problem.