Non-Isolated DC-DC Converters for High Power Applications - Control of the Capacitive Voltage Divider

A non-isolated DC-DC converter is presented, based on the current diverter principle. The converter is foreseen for large power electronic applications where normally the converters are fed from DC supplies at a typical voltage level of around one or two kV. In some specific applications, a primary voltage step-down stage would be used, allowing the adaptation of the voltage of the normal system to a higher DC supply. The Multistage Stacked Boost Architecture MSBA allows a conversion from or to voltage levels higher than the blocking capability of the used semiconductor devices. The paper will describe the control strategy used for the voltage balance of the DC active capacitive divider stage.