Enhancing Stability of Dual Active Bridge Converters with a Long Input Cable

This paper investigates the stability of power converters when connected to a source through a long input cable, a scenario that becomes increasingly relevant in applications where a significant distance separates the converter from the source, such as microgrids, smart grids, and telecommunications. Extended cable length can compromise system performance and potentially introduce instability. To address this issue, two existing solutions are explored: physical damping and virtual damping. In this paper, these solutions are combined to form the "hybrid damping" approach that ensures stable connections while minimizing the need for additional components. Moreover, the parallel damping converter is examined as an alternative method to enhance stability. This converter has the potential to outperform physical, virtual, and hybrid damping while reducing the capacitor value. The research involves the development, simulation, and experimental validation of these damping techniques on a dual active bridge (DAB) converter. However, the presented solutions can be applied to different power converter topologies, yielding improved stability in a wide range of applications.