Series Stacked Modular DC–DC Converter Using Simple Voltage Balancing Method.

This letter proposes a high output voltage dc–dc converter topology with series stacked converter modules. To implement the proposed modular dc–dc converter structure, output voltage balancing of the modules and simplification of the control circuitry were considered the major design objectives. To achieve voltage balancing between the modules, we proposed a split-secondary transformer winding structure and distributed connections to the rectifier circuit blocks. Each transformer includes two secondary windings, with each wire pair connected to a different rectifier circuit. Consequently, one rectifier receives ac power simultaneously by sharing the secondary windings fed from two different transformers. The proposed method was verified using a modular LCC resonant converter, which is widely employed in high-voltage applications. As a result, the control circuit was simplified by using a single controller to regulate the total output voltage and by applying a compact sensing circuit referenced to the output voltage of the module placed at the lowest grounding point. [ABSTRACT FROM AUTHOR]