As part of the energy transition, the share of converter‑based generation in the power system is rapidly increasing, while conventional generation is being phased out. This creates new challenges for maintaining system stability, in particular due to the loss of grid‑forming units and the reduction of the effective system strength . The German Federal Ministry for Economic Affairs’ “System Stability Roadmap” serves as a guideline for ensuring stable and robust system operation with 100% renewable energy and shows that the provision of grid‑forming capabilities in distribution networks must be enabled in the future.

To enable timely practical testing in the local system context of a real distribution grid, the SUREVIVE project is planning and implementing a field test with a grid‑forming battery energy storage system rated at 20 MW and 55 MWh. The pilot systems are connected at the MV/HV transformation level. The aim is to gather knowledge and experience on local system stability under real distribution grid conditions.

To assess potential risks of these field tests, including possible impacts on the grid and on neighboring customers, dynamic network studies using RMS and EMT simulations were carried out in advance. In addition, a measurement campaign was conducted in Fraunhofer ISE’s multi‑megawatt laboratory, examining the behavior of a single grid‑forming inverter with a DC‑connected battery under various grid events, as well as its interaction with other units.

For the first field tests, a local test grid with dedicated connected systems was established, enabling tests to be carried out with limited risk for third‑party customers. In the initial measurement campaigns, various tests in grid‑forming operating mode were performed.

This paper presents the findings of the pre‑studies and the first results from the field tests.