A Dual Active Bridge Converter With Multiphase Boost Interfaces for Single-Stage Bidirectional DC-AC Conversion

A novel bidirectional dual active bridge based dc-ac converter is proposed in this article. The converter has multiphase boost interfaces at both the dc and ac ports. The interleaved operation of the multiphase units cancels the ripple currents and eliminates the input filter requirement. The dc to ac conversion is carried out in a single stage using only eight switches. The converter utilizes the low-frequency and high-frequency components in the inverter output to achieve both power conversion and power transfer across the high-frequency transformer simultaneously. A thorough analysis of the converter is carried out for the proper design of the components. Based on the results, a detailed design method is discussed. A multiresonant controller based phase-shift control is suggested to eliminate the low-frequency ripple in the input dc current. Finally, the effectiveness of the proposed converter is validated using results obtained from a 3-kW hardware prototype.