Network-Aware Flexibility Requests for Distribution-Level Flexibility Markets

Local flexibility markets will become a central tool for distribution system operators (DSOs), who need to ensure a safe grid operation against increased costs and public opposition for new network investments. Despite extended recent literature on local flexibility markets, little attention has been paid on how to determine the flexibility request that the DSOs shall submit to such markets. Considering the constraints that the network introduces (e.g. line and voltage limits), so far it has been unclear how the DSO shall determine how much flexibility it requires and at which network locations. Addressing an open question for several DSOs, this paper introduces a method to design network-aware flexibility requests from a DSO perspective. We consider uncertainty, which could be the result of fluctuating renewable production or demand, and we compare our approach against a stochastic market clearing mechanism, which serves as a benchmark, deriving analytical conditions for their performance. We demonstrate our methods on a real German distribution grid.