Research And Design Of Phase-Shifted Full-Bridge Synchronous Rectifier DC-DC Converter

In recent years,with the rapid development of information technology,especially in the fields of industrial control,aerospace,telecommunications systems,electric vehicles and etc,the demands of high-power supply are increasing.In these applications,electronic devices are usually required to have the characteristics of smaller size,higher reliability,better security and better heat dissipation performance,whereas these characteristics put forward higher requirements for the power supply of electronic equipments.As an excellent power converter which has good performances,the switching loss of the phaseshifted full-bridge DC-DC converter is lower,the topology is simpler and the volume is smaller.It's conform to the power supply of compact and highfrequency,which has been widely used in high-power level conversion occasions.In this paper,phase-shifted full-bridge synchronous rectification DC-DC converter is taken as a research target,rely on convenrional DC-DC converter,take the volume,power level and loss of the converter into consideration,and compared with the phase-shifted full-bridge topology in detail,finally adopt a synchronous rectifier phase-shift full-bridge topology.And the phase-shifting control sequence is studied in deeply,the parameters of the resonant components are accurately calculated,the working process and principle of the main circuit are detailed analyzed,and the design of drive circuit was carefully considered.This DC-DC converter with the input voltage of DC 390 ~ 410 V,the output of DC 48V/31.25 A,the highest conversion efficiency of 94% and rated power of 1.5k W which based on UCC28950 as the control core is successfully developed.And the topology was simulated and verified successfully based on PSpice.The prototype is also test and verify.The successful development of the prototype can not only be used for high-power supply but also as a charger of large-capacity lithium-ion batteries,it can reduce the charging time of electric vehicles.In addition,it will provide the theoretical and practical basis for the development of higher-power rating phase-shifted full-bridge DC-DC converters.