Power Decoupling of Modular Multi-Active Bridge Converter with Accurate Power Sharing Based on Finite Control Set-Model Predictive Control

Compared to traditional multi-active bridge (MAB) converter that share a single multi-winding transformer, the modular multi-active bridge (MMAB) converter employs n-1 independent dual-winding high-frequency transformers (HFTs) and n H-bridge modules interconnected via a high-frequency link (HFL). While this design enhances modularity and scalability, it also introduces cross-coupling among ports. This paper proposes a simple hardware-level decoupling method that eliminates the equivalent inductance of the transfer port, effectively decoupling the multi-input multi-output (MIMO) system into multiple independent single-input single-output (SISO) loops. The decoupling mechanism is analyzed using Fourier series and first harmonic approximation (FHA). Additionally, to address the sluggish response of proportional-integral (PI) control, a finite control set-model predictive control (FCS-MPC) strategy is introduced. This strategy not only achieves fast and robust voltage regulation but also ensures proportional power sharing among multiple energy sources. Finally, simulation results validate the performance of the proposed decoupling method and the effectiveness of the control strategy.