High Efficiency And High Power Density Symmetric Full Bridge DC/DC Converter

With the Rapid development of power electronics technology,DC conversion technology has been the focus of power electronics researchers around the world,which is an important part of power electronic conversion technology.Generally speaking,electronic equipment requires a DC regulated power supply.As the global information develops increasingly,the requirements for power quality of various electronic devices are constantly increasing in the direction of high precision and high stability.And DC power products are required to consume less power and have higher power density,which will bring huge challenges to DC power products.This paper designed a DC/DC converter,which can meet the requirements of the communication system for a wide input voltage range,high power efficiency and high power density.The article designed the circuit according to specific index,which mainly completed the choice of power topology,synchronous rectification technology,the selection of power devices,transformer design and other issues.Meantime,the system small-signal modeling of the main topology's CCM and DCM modes had been worked out,then it had been corrected.To ensure that the converter works in a high steady state,the effectiveness of the system calibration design was verified by the MATLAB simulation software within the input voltage range required by the index.In order to effectively increase the power density,the magnetic components are designed by planar transformer technology.By this way,the transformer is more coupled,and the volume is smaller,and the manufacturing process is more convenient,and the consistency is higher,and the mass production is convenient.Based on the above work,the drive circuit,protection circuit and auxiliary power supply circuit are designed and laid out on the PCB board to complete the overall design of the DC/DC converter.Finally,the theoretical analysis was carried out to verify the experimental results,and a 500W quarter brick 12-layer structure experimental prototype was produced.The main power indicators of the experimental prototype was tested.Its efficiency is as high as 93.5%and its power density is as high as 22.5W/cm~3.Experimental test results show that the DC/DC converter designed in this paper meets the requirements of high efficiency and high power density.