Harmonizing distribution system planning and the operation of integrated DC systems

The ongoing energy transition leads to a drastic increase in the number of power-generating and -consuming units as well as the accumulated installed power in the German power system. The exploitation of operational flexibility offers the potential to reduce the resulting need for power system reinforcement and expansion. The integration of DC systems into existing AC distribution systems provides operational flexibility with assets that by European legislation can be owned by distribution system operators (DSO). Consequently, the DSO can decide on their operational behavior, numbers, location, power rating, and availability. However, the corresponding planning task requires procedures that involve operational considerations. This paper employs a customized optimal power flow based operational strategy for DC links within a planning study, evaluates mutual implications between planning and operation, and derives necessary adjustments for their harmonization. The representative case study on medium-voltage grid planning demonstrates that the integration of controllable DC links in combination with a suitable operational strategy can significantly reduce the number of reinforcement measures required to resolve overloading of grid assets for increasing power demand compared to non-controllable alternatives.

Subjects

distribution system planning

distribution system operation

optimal power flow

hybrid AC/DC system

flexibility

DDC Class

621.3: Electrical Engineering, Electronic Engineering

Funding(s)

Norddeutsches Reallabor, Teilvorhaben: Integrierte Netzplanung

Options

Harmonizing distribution system planning and the operation of integrated DC systems