An Isolated High Voltage Boost Current-Fed DC-DC Converter Based on 1:1 Transformer Multiplier Cells and ZVS Operation

This paper presents a high step up, current fed, interleaved, isolated DC-DC converter with voltage multipliers and ZVS (zero voltage switching). The converter provides zero voltage switching for all active switches and provides a high step up voltage gain that is suitable for very low voltage source applications, such as PV and other renewable sources. In addition, this converter allows the utilization of very low voltage stress switches and diodes. It reduces the current stress by interleaving the input current, and reduces the voltage stress by utilizing a half bridge based multiplier cell integrated configuration at the output voltage while providing high frequency galvanic isolation. The isolation is achieved through the use of 1:1 transformers which are easier to design, and the need for a high turns ratio is absent in this converter. The main theory of operation and the design guideline are presented, as is a laboratory prototype, all to validate the concept.