Operation of a Grid-Forming Converter Controlled by the Flux Vector

This paper proposes a novel control scheme for grid-forming (GFM) converters that utilizes the flux vector as the central state variable to emulate the behavior of synchronous generators. The proposed method introduces a simple yet effective approach to limit both active and reactive currents without the need for internal current control loops, enhancing the converter’s stability and response. By leveraging the flux vector, the system ensures robust synchronization with the grid and reliable operation under various conditions, including frequency deviations and phase disturbances. Unlike traditional methods that rely on virtual impedance or mode switching, this approach provides direct control over voltage and frequency while maintaining inherent stability. The methodology aligns with the operational and performance requirements set by modern grid codes, particularly in low-inertia and weak grid scenarios. The control system architecture integrates synchronized flux orientation, virtual inertia emulation, and a damping mechanism, supporting seamless transitions between grid-connected and islanded modes.

Keywords: Grid-forming, flux vector, current limiter.