Full-Power-Range Instantaneous Flux and Current Control of Three-Phase DAB Converters With Different Winding Configurations

Abstract

The three-phase dual-active bridge (DAB3) converter, a promising topology for high-power DC–DC conversion, suffers from transient overshoots and DC bias under conventional single phase shift (SPS) modulation during a phase shift angle change. While instantaneous flux and current control (IFCC) effectively suppresses transient flux/current overshoots and DC bias in Y–Y-connected transformers and phase shift angle below $\pi /3$ , its applicability to different winding configurations and wider phase shift angle range remains unexplored. This is particularly important for DAB3 converters with $\Delta $ -connected windings, which experience higher switch current stress. This article presents a generalized space-vector model to evaluate the transient performance of DAB3 converters with Y–Y, Y– $\Delta $ , and $\Delta $ – $\Delta $ configurations over the full power range. The analysis reveals that the original IFCC parameters are not optimal for the Y– $\Delta $ configuration, and an improved distribution factor is derived to minimize flux linkage overshoots. Furthermore, an integration scheme combining the IFCC method with an active phase current balancing strategy is proposed to mitigate three-phase parameter inconsistencies. Simulation and experimental results are provided to validate the analysis, demonstrating enhanced transient performance in extended operating conditions.