在此研究中，本文實現一基於數位控制1MHz，480W 氮化鎵同步整流降壓轉換器。使用氮化鎵高電子遷移率電晶體(GaN HEMT)原因在於相較於碳化矽電晶體，氮化鎵電晶體的閘極電荷(Qg)以及輸出電容(Coss)大幅降低，氮化鎵具有更低的驅動損耗以及更短的死區時間之電路收益。因此，在高頻應用中，氮化鎵電晶體優於碳化矽電晶體。在實現同步整流降壓轉換器的情況下，使用了兩種控制方法進行比較。其中這些控制方法為通過模擬來進行開發以及驗證。而後在同步整流降壓轉換器上進行單自由度PI和雙自由度PI的應用、測試以及比較。最後根據實驗結果，相較於單自由度PI控制法，雙自由度PI控制法對於安定時間和電壓變動量的改善率為91.19%和37.63%。

In this study, a digitally controlled, 1 MHz, 480 W GaN based synchronous buck converter is implemented. GaN High Electron Mobility Transistors (GaN HEMT) are adopted because they have lower driving loss and shorter deadtime circuit benefits due to significantly reduced gate charge (Qg) and output capacitance (Coss) compared to silicon-based MOSFETS. Hence, GaN HEMTs show significant advantages over silicon-based MOSFETs in high-frequency applications. A comparison among two control strategies is also performed using the implemented synchronous buck converter. These control strategies are developed and validated by simulations. The 1-degree of freedom (DOF) PI, and 2-DOF PI are applied, tested and compared on the synchronous buck converter. According to the experimental results, 2-DOF PI controller can improve the transient time and overshoot by 91.19 % and 37.63 % comparing with 1-DOF PI controller.

[1] Yong Xie and Paul Brohlin, “Optimizing GaN performance with an integrated driver, ” March 2016.
[2] Dalvir K. Saini, “Gallium Nitride: Analysis of Physical Properties and Performance in High-Frequency Power Electronic Circuits,” B. S., Wright State University, Dayton, Ohio, United States of America, 2013.
[3] Alex Lidow. Johan Strydom and Michael de Rooij. David Reusch, “GaN Transistors for Efficient Power Conversion Second Edition,” September 2018.
[4] 吳義利，「切換式電源轉換器」第二版，文笙書局股份有限公司，民國104年9月。
[5] 鄭勝文，「刀鋒伺服器用多相式降壓直流-直流轉換器研製」，國立台灣科技大學電機工程系碩士學位論文，2014年。
[6] J. Y. Liou, L. Wang and R. L. Lin, “Compensator Design of Single-phase DC-DC Synchronous Buck Converter,” Proc. Of the 6th Taiwan Power Electronics Conference, pp.815-20, 2007.
[7] A. Ugur, and M. Yilmaz, “A GaN-Based Synchronous Buck Converter for High Power Laser Diode Drive Applications,” BALKAN JOURNAL OF ELECTRICAL & COMPUTER ENGINEERING, Vol. 6, No. 1, February 2018.
[8] GaN Systems, “GN001 Application Guide Design with GaN Enhancement mode HEMT, ” August 2016.
[9] 黃友銳、曲立國，「PID控制器參數整定與實現」，科學出版社，2010。
 
[10] 郭俊廷，「具有雙自由度數位控制器之降壓型直流/直流轉換器的研製」，國立台北科技大學電機工程系碩士學位論文，2008年。
[11] R. W. Erickson, and D. Maksimovic, “Fundamental of Power Electronics,2nd edition, ” Kluwer Academic Publishers, 2001.
[12] Mark A. Haidekker, “Linear Feedback Controls: The Essentials,” Elsevier, 2013.
[13] 王曉東，MATLAB工具箱Sisotool工具箱在控制系统補償器中的應用，遼寧科技學院學報，2006 年。
[14] 黃嘉偉，「適用於快速變動環境之太陽能最大功率追蹤技術研究」，國立台灣科技大學電機工程系碩士學位論文，2012年。
[15] Texas Instruments, “LMG1205, ” Data sheet, 2018.
[16] GaN Systems, “GS61008P Bottom-side cooled 100 V E-mode GaN transistor, ” Data sheet, 2018.
[17] 曾百由，「數位訊號控制器原理與應用」，宏友圖書開發股份有限公司，民國96年11月。
[18] 賴文能、林國祥、高志暐，「數位信號處理」第三版，高立圖書有限公司，2007年。
[19] Texas Instruments, “TMS320F28004x Piccolo Microcontrollers,” Available at: http://www.ti.com/.
[20] 賴志嘉，「具增強型氮化鎵高電子遷移率電晶體1MHz DC-DC LLC諧振轉換器之研製」，國立成功大學電機工程系碩士學位論文，2018年。
[21] GaN Systems, “GS61008P-EVBHF GaN E-HEMT Half Bridge Evaluation Board, ” User Guide, 2018.
[22] GaN Systems, “GS66508B=EVBDB 650V GaN E-HEMT Evaluation Board, ” User Guide, 2016.

[23] Texas Instruments,“1-MHz, 3.3V,High-Efficiency Synchronous Buck Converter With TPS43000 PWM Controller, ”User Guide, 2002.
[24] 朱峻毅，「具同步整流之數位控制降壓轉換器研製」，龍華科技電機工程系碩士學位論文，2019年。