A new high efficiency and high power density 48V to 1V converter

Abstract

This paper presents a new converter of high efficiency and high power density power supply that can significantly reduce the regulated converter rated power and increase the unregulated converter rated power, so the efficiency of the power supply can be improved. The LLC DCX converter can be very high efficiency and can work in a very high switching frequency which means high power density, but it can not regulate the output voltage, so the LLC DCX converter is an unregulated converter [1]. The four switch Buck Boost converter can regulate output voltage, step up and step down, but its efficiency and power density is low because of its hard-switching feature [2]. The four switch Buck Boost converter can cascade with the LLC DCX converter to make up a two stages architecture converter for the 48V-to-1V application [3]. As the cascade structure, the regulated converter rated power is 100% which deteriorates the efficiency and power density. The unregulated converter rated power ratio of the proposal converter can be increased to at least 73% so the new topology has an efficiency close to LLC DCX’s.