Applying Normally-off GaN HEMTs for Coreless High-frequency Wireless Chargers  

作　　者：Wei Qian Xi Zhang Yongsheng Fu Juncheng Lu Hua Bai 

机构地区：[1]School of Mechanical Engineering,Shanghai Jiao Tong University(SJTU),Shanghai,China [2]Institute of Automotive Engineering and National Engineering Lab for Automotive Electronics and Control Technology,SJTU [3]University of Michigan Dearborn [4]GaN Systems Inc,Ottawa,K2K 3G8 Canada [5]University of Michigan-Dearborn as associate professor

出　　处：《CES Transactions on Electrical Machines and Systems》2017年第4期418-427,共10页中国电工技术学会电机与系统学报（英文）

摘　　要：Wide-bandgap(WBG)devices such as Gallium-Nitride(GaN)High Electron Mobility Transistors(HEMTs)have become popular in the power electronics industry as they offer a lower switching loss,higher thermal capability and higher power density than conventional silicon devices.As an attempt of applying WBG devices to the wireless charging technology,this paper adopts two different types of normally-off GaN HEMTs.One adopts the cascode structure provided by Transphorm Inc,operated under 800kHz to charge a battery pack on an electric scooter at 48 V/500W,with the air gap between the transceiver and receiver of~10cm.The other is enhancement-mode GaN HEMTs provided by GaN Systems Inc,operated at~6MHz to use one transceiver to charge multiple cell phones@~20W.Both of these chargers have no magnetic cores to reduce the cost and weight.Experimental results show both types of GaN HEMTs significantly increased the charging efficiency over conventional Si devices.Challenges of applying such fast-transition devices are discussed,e.g.,common-source inductance and the gate-drive-loop parasitic.

关 键 词：COOLMOS GaN HEMT Wide-bandgap semiconductor wireless power transfer zero voltage switching. 

分 类 号：TN3[电子电信—物理电子学]