Evaluation of TSO–DSO Coordination Schemes for meshed-to-meshed configurations: lessons learned from a realistic Swedish case study

Abstract

This paper proposes comprehensive models for assessing different Coordination Schemes (CSs) in the context of distributed flexibility procurement used for balancing and congestion management at local and transmission grids. The proposed models focus on the coordination between the TSO and the high voltage distribution levels, introducing the meshed-to-meshed topology with multiple TSO–DSO​ interface substations. The models are applied to a realistic case study of the Swedish power system, with faithful representations of the transmission grid and a subtransmission grid from the Uppsala region. A one-year period case study base on real data is conducted, which is then subject to different sensitivity analyses. Real data from the TSO and the DSO validate results. From the DSO side, the paper presents and quantifies the effectiveness of the Local Flexibility Market (LFM) for the DSO in the Swedish context in reducing potential subscription-level penalties in a Multi-level CS while also exploring aspects of different LFM market designs. This paper shows the potential aspects of information exchange both for TSO and DSO in different CSs, as well as between Flexibility Service Providers (FSP) and the procuring System Operator. The proposed market designs are more transparent and easier to implement, limiting the information exchanged between TSO and DSO and allowing the FSP to know their impact over congestions to be solved.