摘要
同等电压应力下的GaN器件相比Si器件具有更低的导通电阻Rds(on)(on-resistance)及门极充电电荷Qg,能够大幅降低驱动和开关损耗,有利于提高变换器效率及功率密度。在低压小功率场合的超高频VHF(very high freque-ncy)谐振反激变换器中,提出了一种集成空芯变压器,大幅减小了印制电路板PCB(printed circuit board)面积,提高了功率密度。同时通过有限元分析FEA(finite element analysis)设计样机结构,确保变压器磁场不会影响其他器件。应用该方案搭建了3台5 V输入、5 V/2 W输出的超高频谐振反激变换器,分别为20-MHz Si方案、30-MHz GaN方案和50-MHz GaN方案。其中,50-MHz GaN方案样机实现了39.4 W/in3的功率密度,相比20-MHz Si方案提升41%。同时,在效率接近的前提下,3台变换器的高度都不足商用产品的一半。
Compared with a Si device under the same voltage rating,the GaN device has a lower on-resistance(Rds(on))and gate charge(Qg),which can significantly reduce the drive and switching loss and is helpful in improving the converter’s efficiency and power density.In a very-high-frequency(VHF)resonant flyback converter under a low-voltage and low-power scenario,an air-core transformer integration method is proposed,thereby significantly reducing the printed circuit board(PCB)area and improving the power density.Meanwhile,a prototype structure is designed using the finite element analysis(FEA)to ensure that the transformer magnetic field does not affect other components.This scheme was applied to three VHF resonant flyback converters(input of 5 V and output of 5 V/2 W)operating at 20 MHz with Si,30 MHz with GaN,and 50 MHz with GaN,respectively.The 50-MHz GaN prototype achieved a power density of 39.4 W/in3,which was 41%higher than that of the 20-MHz Si prototype.Moreover,under the premise of similar efficiencies,the overall height of all the three prototypes was less than half of the commercial products.
作者
顾占彪
许可
唐家承
李志斌
张之梁
任小永
GU Zhanbiao;XU Ke;TANG Jiacheng;LI Zhibin;ZHANG Zhiliang;REN Xiaoyong(The 13th Research Institute,China Electronics Technology Group Corporation,Shijiazhuang 050051,China;Aero Engine Corporation of China,Wuxi 214000,China;Areo-Power Sci-tech Center,Nanjing University of Aeronautics and Astronautics,Nanjing 211106,China)
出处
《电源学报》
CSCD
北大核心
2020年第5期19-27,共9页
Journal of Power Supply
基金
国家优秀青年科学基金资助项目(51722702)
中央高校基本科研业务费资助项目(NP2019101)。
关键词
氮化镓
超高频
高功率密度
变压器集成
GaN
very high frequency(VHF)
high power density
transformer integration
