| Title |
A Study on the Efficiency Prediction of Low-Voltage and High-Current dc-dc Converters Using GaN FET-based Synchronous Rectifier |
| Authors |
Jea-Woong Jeong ; Hyun-Bin Kim ; Jong-Soo Kim ; Nam-Joon Kim |
| DOI |
https://doi.org/10.6113/TKPE/2017.22.4.297 |
| Keywords |
Efficiency prediction ; Full bridge DC-DC converter ; GaN FET ; Power loss ; Synchronous rectifier |
| Abstract |
The purpose of this paper is to analyze losses because of switching devices and the secondary side circuit diodes of 500 W full bridge dc-dc converter by applying gallium nitride (GaN) field-effect transistor (FET), which is one of the wide band gap devices. For the detailed device analysis, we translate the specific resistance relation caused by the GaN FET material property into algebraic expression, and investigate the influence of the GaN FET structure and characteristic on efficiency and system specifications. In addition, we mathematically compare the diode rectifier circuit loss, which is a full bridge dc-dc converter secondary side circuit, with the synchronous rectifier circuit loss using silicon metal-oxide semiconductor (Si MOSFET) or GaN FET, which produce the full bridge dc-dc converter analytical value validity ??to derive the final efficiency and loss. We also design the heat sink based on the mathematically derived loss value, and suggest the heat sink size by purpose and the heat divergence degree through simulation. |