A combined front end DC/DC converter

Holdup time is a special requirement for front end DC/DC converters. It forces the converter to operate in a wide range for input voltage, which greatly degrades the converter's normal efficiency. In this paper a new front end DC/DC converter, a novel combination of an asymmetrical half bridge and a baby-boost with special control, is proposed. The baby-boost stands by under normal conditions and operates inherently only during the hold up time. As a result, the performances of high efficiency, power density and wide range of input voltage are all obtained. Topology and operation principles are presented with simulated and experimental results given in detail.