An Inductance-Current-Minimization Optimization Scheme Based on Hardware Decoupling for Modular Multiactive-Bridge Converter

Modular multiactive-bridge (MMAB) converter is increasingly recognized as a potential solution for efficient power conversion in the integration of distributed energy resources, storage systems, and loads. However, optimizing MMAB converters for high-efficiency operation remains a challenge due to the inherent coupling across ports. To address this problem, this article proposes an inductance-current-minimization optimization scheme based on a hardware decoupling method. The decoupling across ports is achieved by eliminating the inductance at one of the ports, which simplifies the complexity of the system significantly. Based on the decoupled MMAB converter, an optimization scheme is proposed to minimize the root mean square value of the inductor current. Compared with the conventional modulation scheme, this scheme can reduce the inductor current and expand the soft-switching region across various power ranges and voltage ratios, thereby enhancing the operation efficiency. Furthermore, the proposed scheme is based on analytical solutions, enabling online implementation without the need for lookup tables and scalable to accommodate any number of ports. The effectiveness of the proposed scheme has been verified by a series of simulations and experiments based on a four-port MMAB converter prototype.