Firstly introduced in [24], DAB3 topology (Fig. 3) has
one more phase-leg added in both primary and secondary
bridge, and one three-phase transformer is connected for
isolation and voltage regulation instead of the single-phase
one in DAB1. Similar control scheme can be applied to
DAB3, with fixed frequency and complementary 50% duty
cycle for upper and bottom switches, but the phase angle
between phase legs on one side is 120°, instead of 180° in
DAB1. DAB3 is also a bidirectional converter. The energy
flows through the leakage inductance of the transformer,
and the direction and amount are determined by the phaseshift-
angle between the two switch bridges. And there is a
natural ZVS capability for both bridges of DAB3 too,
except at very light load condition.