The increasing integration sources into power grids requires adaptive strategies to maintain stability, especially in island and distribution grids. This article presents the development of a 200 kVA battery inverter with grid-forming control for the integration of photovoltaics (PV) into island grids. The inverter uses a three-phase Active Neutral Point Clamped (ANPC) topology with two interleaved legs and a DC-DC converter with flying capacitor topology. According to grid connection standard VDE-AR-N 4105, PV systems must disconnect from the grid in the event of unintended islanding. However, the integration of renewable energy is crucial for future grid reliability, especially in isolated or disaster-affected regions. The energy management system aims to integrate PV systems into the grid during island grid operation, prevent battery overcharging, and ensure grid-serving functionalities. Using the VDE 4105 guidelines, the system controls PV active power by adjusting the grid frequency and optimizes the battery’s state of charge (SoC) for reliability and durability. Power-Hardware-in-the-Loop (P-HiL) laboratory tests demonstrate the effectiveness of the system in maintaining uninterrupted grid operation and adapting PV generation to the needs of the microgrid.
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