Bidirectional Dual Active Bridge Series Resonant Converter with pulse modulation

This paper presents a new modulation technique for the Bidirectional Dual Active Bridge Series Resonant Converter (DAB SRC). The main feature of the proposed modulation is the elimination of the switching losses of the active devices that allows operating the DAB SRC at high switching frequency (500 kHz, 1kW converter). Thus, the transformer design is more compact and the resonant inductor is entirely composed of the transformer leakage inductance; no external inductor is needed. The selected application to validate the concept is a 1 kW 270 V–28 V bidirectional dc/dc converter for the future More Electric Aircraft (MEA). The converter consists of two stages: the first one is a DAB SRC with a new pulse modulation technique and the second one is a boost converter which regulates terminal voltage of DAB SRC. The feasibility of the proposed modulation technique is verified in a 700 W preliminary prototype and the converter behavior is validated.