The low-voltage grid model of Hittistetten based on 2024 grid data, obtained from the local grid operator (Stadtwerke Ulm/Neu-Ulm Netze GmbH), includes a total of 112 house connections, three transformers, and 83 photovoltaic (PV) systems. The network is structured as a radial network, with the three transformers operating independently under normal conditions and only being interconnected during failures or maintenance. The transformers are from different manufacturers, but all have a rated apparent power of 630 kVA.
Based on this grid data, year-round simulations for 2023 were conducted, utilizing synthetic load profiles for consumers and generation profiles for PV systems. For the simulation, load profiles were generated by a load profile generator based on a bottom-up approach. In this approach, the individual components of a household were specified and simulated separately. The sum of all components ultimately forms the household’s total load profile. Since personal information, such as household structures and employment statuses, could not be disclosed, these parameters were stochastically varied to create the most realistic scenarios possible. To perform calculations with consistent and normalized values, the load profiles generated by the load profile generator were normalized to an annual consumption of 1,000 kWh and then scaled comply with the actual annual consumption measured by the electricity meters in Hittistetten.
The simulation results presented in the collaborative platform includes the most interesting parameters for grid operators. These are maximal and minimal voltage of the grid as well as the maximal loading of all grid components. These parameters must be maintained within predefined limits in normal operating conditions as described in the European norm (DIN EN 50160).
