Modeling of a Matrix-Type Dual Active Bridge in Three-Phase AC Grid Applications

Abstract

This paper proposes a control-oriented modeling framework for the matrix-type dual active bridge (MT-DAB), a single-stage isolated ac–dc converter. The input matrix bridge is modeled as a space-vector–controlled current-source inverter, while the secondary stage is treated as a dual-phase-shift (DPS) controlled DAB. A generalized averaged large-signal model is derived by exploiting the close correspondence between the MT-DAB’s selected pulse pattern and conventional DPS modulation. Linearization around operating points yields a compact linear time-invariant (LTI) small-signal model that captures the dominant dynamics with only the first harmonic. The models enable systematic synthesis of control loops for independent regulation of output power and input power factor, eliminating the need for precalculated switching instants. Validation against switched PLECS simulations shows high fidelity, the inductor-current dynamics are reproduced with near-exact agreement, and output-voltage transients are predicted accurately for moderate steps.