| Abstract |
Isolated dc-dc converters are increasingly being used in many industrial and utility applications suchas shipboard, hybrid and electric vehicles, microgrids, etc., for integrating the dc sources and storagedevices. A modified dual transformer based asymmetrical dual bridged isolated dc-dc (MDT-ADB)converter is proposed in this paper. MDT-ADB consists of three stages: input, isolation, and output. Theinput stage consists of a full bridge converter (FB), the isolation stage consists of two high-frequencytransformers, and the output stage consists of a semi-active three-leg converter (STL). In the isolationstage, the primary windings of the transformers are connected in series and the secondary windings areconnected in parallel across the load via STL to share the load power equally which decreases thecurrents flowing through some of the switches of STL. Therefore, the switching losses of these switchesare reduced. Further, MDT-ADB results in reduced circulating currents in the transformer windings aswell as in a wider range of the output voltage and power as compared those in the existing dualtransformer based asymmetrical dual bridge converter (DT-ADB). Additionally, all switches of MDTADBcan be operated with soft switching to obtain reduced losses. A detailed analysis of the modelingand control of MDT-ADB is presented. The discussed theoretical analysis is verified using simulationsand experimental results. |
