Model Predictive Control of a High-Turn-Ratio Dual-Active Bridge Converter Considering Interlinking Inductances

Within a more-electric aircraft (MEA) dc power distribution system, dual-active bridge (DAB) converters are employed to manage power transfer between different dc buses, or power transfer from/to the energy storage devices, for example, batteries. However, due to the relatively high current slew rate and large current amplitude in the low-voltage (LV) H-bridge, the interlinking inductance between the LV board and the transformer becomes nonnegligible, as it introduces a noticeable voltage drop across the transformer secondary side, potentially leading to inaccurate power control. To address this issue, this article develops a comprehensive mathematical model of DAB converters for a moving discretized control set model predictive control (MDCS-MPC) approach to minimize steady-state errors. The proposed model explicitly incorporates the effect of interlinking inductance and further investigates the relationship between the transferred power and the resulting voltage drop on the LV side. Finally, the effectiveness of the proposed model and MDCS-MPC method is validated through the experimental results on a 1000-W DAB prototype, with transient performance comparisons against other conventional control strategies.