Evaluation of antiparallel SiC Schottky diode in SiC MOSFET phase-leg configuration of synchronous rectifier
Journal article, 2023

The MOSFET synchronous rectification (SR) is widely used to reduce the conduction loss during the freewheeling period. Due to the wide band gap of silicon carbide (SiC), the intrinsic body diode of SiC MOSFET exhibits a high voltage drop. Therefore, SiC Schottky diodes (SBD) and SiC MOSFETs are usually used in reverse parallel to reduce power loss. However, the increase of equivalent junction capacitance due to the addition of an external SiC SBD could bring larger turn-on current on opposite power transistor of the phase-leg. Furthermore, as the parasitic inductance associated with layout hinders the prompt transfer of current between SiC SBD and body diode, the external SiC SBD cannot be fully utilized, and it may deteriorate the overall performance, especially at heavy load. We comprehensively compare power losses when SiC SBD are antiparallel or not, at different working conditions, including different layout compactness, load current and dead time. It's hard to get the effect of loss reduction loss when add antiparallel SiC SBD due to the parasitic inductance induced by the layout. The results can provide a guidance to properly select SiC SBD in a phase-leg configuration under SR mode for freewheeling during the dead time.

SiC MOSFET

Phase-leg configuration

Anti-parallel

Synchronous rectification

Author

Haihong Qin

Nanjing University of Aeronautics and Astronautics

Rongxia Huang

Nanjing University of Aeronautics and Astronautics

Haoxiang Hu

Nanjing University of Aeronautics and Astronautics

Qian Xun

Chalmers, Electrical Engineering, Electric Power Engineering

Wenming Chen

Nanjing University of Aeronautics and Astronautics

Dafeng Fu

Nanjing University of Aeronautics and Astronautics

Energy Reports

23524847 (eISSN)

Vol. 9 337-342

Subject Categories

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1016/j.egyr.2023.09.126

More information

Latest update

10/24/2023