Dynamic optimal power flow for dimensioning and operating quarter based storage in low voltage grids

Abstract

This paper investigates the application of Dynamic Optimal Power Flow (DOPF) in low voltage grids. First, a dimensioning tool for quarter based storage in low voltage distribution grids is presented for the use case of self-consumption while supporting the network. In a DOPF simulation with an optimization horizon of an entire year, storage capacity and converter power have certain costs and are treated as variables. The result is therefore the optimal storage and converter size with a maximized social benefit and minimized electrical losses. The large-scale optimization problem is only tractable due to a novel modelling approach. The dimensioning methodology is tested on 26 realistic low voltage distribution networks from southern Germany. The second part of this work deals with the optimal operation of the storage, where a receding horizon method is adopted. The impact on system costs are investigated when applying solutions of storage operation to a system where load and RES differ from the forecast which was used in the optimization. It shows that storage investments can pay off for networks with a yearly energy production close to the yearly energy demand.