A low cost implementation of a dual-stage interleaved bidirectional boost converter

This paper describes the design and verification of a converter that allows bidirectional energy flow between a 48 volt battery storage system and a 350 volt DC grid. Multiple converter designs are discussed, leading to the selection of multiple parallel dual-stage bidirectional synchronous buck-boost converters, with the option to apply distributed interleaving. To improve efficiency, multiple synchronous buck-boost converters are in parallel, and depending on the required power level, converters can be enabled or disabled during operation. The interleaving is directly adjusted depending on the number of operational converters. A high efficiency is thus realized at different power levels. Three busbars are applied, input, intermediate stage and output. The busbars are placed vertically to allow a flexible exchange of converters. The gatedriver is constructed on an exchangeable pcb, allowing swapping to newer designs, in case of component shortage.