Smart distribution grids for Germany's Energiewende

The German “Energiewende” constitutes a major challenge for the energy supply system. The present paper shows that the increasing number of volatile distributed generators and large consumers requires a coordination to avoid an expensive grid expansion. After summarizing the basic application areas of smart grid systems, a specific implementation of a decentralized smart grid approach is presented. This solution is able to estimate the grid state via a cost efficient minimal set of sensors. Via a three-stage control algorithm deviations from the permitted grid states can be remedied autonomously. Finally, future development potentialities like an EV-charging add-on and a system expansion to medium voltage grids are discussed.