.. _overlying-grid-flex: Overlying-grid requirements =========================== In plain terms -------------- A distribution grid does not exist in isolation: it hangs off the high-voltage (transmission) grid above it. When the whole system is planned together — for example eDisGo coupled with `eTraGo `_ via `eGo `_ — the upper grid level may *require* the distribution grid to dispatch its flexibilities in a certain way (e.g. a given curtailment, a storage or DSM profile). eDisGo stores these requirements and can pass them to the optimisation as additional constraints. Data ---- The :class:`~edisgo.network.overlying_grid.OverlyingGrid` container (``edisgo.overlying_grid``) holds the requirements handed down from the overlying grid, such as: * ``renewables_curtailment`` — required curtailment of renewable feed-in, * ``storage_units_active_power`` / ``storage_units_soc`` — required aggregate storage-unit dispatch and state of charge, * ``dsm_active_power`` — required DSM utilisation, * ``electromobility_active_power`` — required aggregate EV charging, * ``heat_pump_decentral_active_power`` / ``thermal_storage_units_decentral_soc`` — required decentral heat-pump operation, * ``heat_pump_central_active_power`` / ``thermal_storage_units_central_soc`` / ``feedin_district_heating`` — the corresponding central power-to-heat / district-heating requirements. The helper :py:func:`~edisgo.network.overlying_grid.distribute_overlying_grid_requirements` returns a new EDisGo object in which these aggregate requirements are distributed onto the individual components, with a distribution key that differs per flexibility (EV by flexibility-band power, storage by installed capacity ``p_nom``, power-to-heat by ``p_set``, DSM by its potential bands, and curtailment proportional to current feed-in). Use in the optimisation ----------------------- The high-voltage requirements are honoured by the OPF versions that add HV constraints — ``opf_version`` 3 and 4 of :meth:`~edisgo.edisgo.EDisGo.pm_optimize` (see :ref:`flexibility-opf`). This keeps the local, distribution-level flexibility schedule consistent with what the transmission-level planning expects, so the two levels can be optimised coherently.