Research On The Design Of High Power Density Power Supply Based On GaN Devices

The power supply of DC/DC modules has a very important role in today’s society for the field of electronics,automobiles,care medical,and aerospace.Among the spacecraft,the DC/DC module power supply maintains the normal operation of all parts of the astronauts.In order to reduce the launch cost of the astronauts and increase more effective loads,light quality,small volume,high efficiency,high power density,high reliability,and low loss have become an inevitable trend of its development.The research and application of the third-generation semiconductor has promoted the development of module power.The GaN FET has the advantages of large banned bandwidth,high electron saturation speed,radiation resistance,fast switching speed,low switching loss,and is more suitable used in high-frequency,high-efficiency space environment.The increase in switching frequency can reduce the energy storage components and magnetic components,thereby reducing the volume of the power supply of the entire module and increasing the power density.This article has made a detailed analysis of the new device GaN crystal tube,master the physical characteristics and electrical characteristics of GaN HEMT,calculate the switch loss and guide loss,and design the drive circuit.According to the comparison analysis of the basic topology types,the two-switch forward converter is selected as the main circuit topology.It discusses the working principle of two-switch forward converter,and determines the various parameters of the main circuit according to the needs.Ring circuit,ensure the steady-state characteristics and dynamic characteristics of the circuit.Calculate and design related parameters of the main circuit high-frequency transformer and filter inductance,use Maxwell software to simulate the transformer to build a mold,and optimize the transformer winding method to reduce the winding resistance of the winding,thereby reducing the energy loss of the transformer,and making the physical object of the transformer and the induction which are used in the experimental prototype.In order to ensure the reliability and stability of the power supply,this article has calculated the thermal loss of the main device in the module power supply,and used ANSYS Icepak software to establish a module power thermal simulation model to analyze the temperature of the module power supply within 39K.Using the high-frequency advantage of GaN HEMT,the GaN HEMT is used as the main circuit switching tube,the synchronous rectifier,and the renewal pipe to make a high-frequency switching power experimental prototype,whose input voltage is 100V±20V(DC),the output voltage is 28V(DC),the switching frequency is 800k Hz and the rated power is 150W.Through the experimental test,the full load efficiency of the experimental prototype is91.60%,and the power density is about 4.69W/cm~3,which increases by 20.8%from the traditional aerospace module power density,effectively increased the efficiency and power density of aerospace module power.And the tests verify the various indicators of the power design and verify the effectiveness and reliability of the compensation ring design.This article provides technical support and design ideas for the application of GaN devices in the power supply of the aerospace module.