A Comparative Study of Freewheeling Methods for eGaN HEMTs in a Phase-leg Configuration
Journal article, 2021

Enhancement Gallium nitride high-electron mobility transistors (eGaN HEMTs) have been developed with lower conduction losses and higher switching speed compared to MOSFETs. Self-commutated reverse conduction (SCRC) mechanism determines no reverse recovery phenomenon but larger reverse conduction voltage drop of eGaN HEMTs than the body diodes in traditional Si MOSFETs or other freewheeling diodes. To reduce the large reverse conduction loss of eGaN HEMTs, the performance of different freewheeling methods for eGaN HEMTs in a phase-leg configuration is compared in this paper. Firstly, the reverse conduction mechanism and characteristics of eGaN HEMTs are analyzed. Then, four freewheeling ways for eGaN HEMTs are introduced, and the equivalent circuits are also given and analyzed. A double pulse test platform is established to further explore the influence of the freewheeling ways on the conduction and switching characteristics. Finally, the total losses of a phase-leg configuration with different freewheeling ways based on a buck converter is analyzed and compared. The paper aims to give a guidance to properly select freewheeling ways for eGaN HEMTs under different operation conditions.

enhancement gallium nitride high-electron-mobility transistors (eGaN HEMTs)


Body diodes


reverse conduction


Haihong Qin

Nanjing University of Aeronautics and Astronautics

Zihe Peng

Nanjing University of Aeronautics and Astronautics

Ying Zhang

China Electronic Technology Group Corporation

Qian Xun

Chalmers, Electrical Engineering, Electric Power Engineering

Dafeng Fu

Nanjing University of Aeronautics and Astronautics

IEEE Journal of Emerging and Selected Topics in Power Electronics

2168-6777 (ISSN) 2168-6785 (eISSN)

Vol. 9 3 3657-3670 9162072

Subject Categories

Energy Engineering

Other Materials Engineering

Other Electrical Engineering, Electronic Engineering, Information Engineering



More information

Latest update