LLC 諧振電路基於氮化鎵的實現

Abstract

本文設計了一個輸入電壓為145伏特至165伏特最大輸出功率300瓦，輸出電壓為12伏特輸出電流25A且最高轉換效率達91%的LLC諧振轉換器。並使用交通大學自製的氮化鎵蕭特基二極體製作切換速度提升電路，利用氮化鎵材料本身具有的優秀材料特性，如：高崩潰電壓、高電子飽和速度以及高電流密度，有效地降低切換損耗。最後本研究嘗試使用氮化鎵來取代原有的高功率開關，並發現在沒有切換速度提升電路的狀態下使用氮化鎵(GaN)當開關比起使用MOSFET時，效率在輕載、半載與滿載時分別改善1.04%、0.20%和0.47%。

The purpose of this study is designing a LLC resonant circuit with DC input 145V~165V and DC output 12V/25A. Maximum efficiency can be reached to 91%. This study designs the faster switching circuit based on NCTU_GaN_SBD. The GaN has excellent material characteristics, such as high breakdown voltage, high electron saturation velocity and high current density, and it can effectively reduce switching losses. Finally, this research tries to use the GaN as switch to replace MOSFET. This study finds that the efficiency of LLC resonant circuit based on GaN is better than MOSFET. It can improve the efficiency 1.04% at light load, 0.20% at half load and 0.47% at full load.