Minimizing Circulating Current in Active Bridge Multilevel Converter Using HFL Analysis

Multilevel Active Bridge (AB)-based converters are potential candidates for DC applications due to their ability to integrate multiple sources while minimizing volume. This paper presents an analytical and simulation-based investigation of circulating current behavior and power factor performance in AB-based multilevel converter structures. A High-Frequency Link (HFL) analysis framework is developed to characterize voltage, current, and power transfer waveforms, providing insight into reactive power generation and its impact on overall efficiency. By introducing a modulation-based control approach, the proposed converters significantly reduce circulating currents and enhance the power factor, particularly under varying phase shift conditions. Compared to conventional Quadruple Active Bridge (QAB) topologies, the discussed multilevel architectures offer reduced transformer complexity and improved power quality, making them suitable for demanding applications such as electric vehicles and aerospace systems.