Development of a novel combined converter with low-voltage and high-current input, high power and high-voltage output

Abstract

A novel combined converter topology with high current and low voltage of the input-end and high voltage of the output-end is presented to meet the demands of high reliability and high power density in some power supply applications. By connecting in parallel two-transistor forward converter modules and power switches simultaneously in the input-end, and by connecting in parallel/series the converter modules in the output-end, the proposed converter has many advantages such as natural current-sharing among power switches, natural voltage-sharing between output-capacitors, high voltage gain, no risk of direct short-through failures in the input DC link, low voltage stress on second-side diodes, and small volume of input and output filters. Those make the combined converter topology very attractive and suitable for high input current, high output voltage, and high power applications, and it has been successfully applied in a high power supply system.