Transmission system congestion management with demand-side flexibility resources considering distribution system performance improvement

The lack of clarity regarding the participation of transmission system operators and their collaboration with distribution system operators in local flexibility markets is one of the challenges of these markets. So in this study for managing transmission system unpredicted congestions due to sudden increase in system load with demand side resources, a bilevel flexibility market is presented. The first level of this market is related to providing TSOs with required services and only DSOs can participate in this level. The second level consists of local markets in each distribution system that are managed by DSOs and prosumers submit their flexibility bids in these markets. In this paper, DSO and TSO coordination is based on DSO-managed models. This means that DSO aggregates all flexibility bids in distribution networks and modifies prosumers' cost functions considering distribution network loss minimization. The DSO then submits these bids to the first level flexibility market. Modifying prosumers' cost functions is an optimization problem that is solved using water cycle optimization algorithms.