應用於無線功率傳輸的可適性交流-直流轉換器

Adaptive AC-DC Converters for Wireless Power Transmission

羅業興(Ye-Sing Luo)

指導教授 ： 劉深淵

國立臺灣大學/電機資訊學院/電子工程學研究所/博士(2017年)

https://doi.org/10.6342/NTU201701488

摘要

隨著物聯網、穿戴式裝置與可植入性醫療元件的發展，無線功率傳輸受到相當大的關注。在相關應用中，發射端所送出的能量，經由線圈/天線傳遞後，可在無線裝置上產生交流電壓。為了將交流電壓轉換為直流電壓，以提供裝置運作，交流-直流轉換器受到廣泛地使用。交流-直流轉換器的核心，常使用二極體連接的電晶體，或是使用比較器為基礎的主動式二極體。然而，二極體連接的電晶體與主動式二極體分別受限於電晶體的臨界電壓以及比較器的延遲開啟與關閉，使得交流-直流轉換器輸出電壓與功率轉換效率下降。因此，提高交流-直流轉換器的輸出電壓與功率轉換效率，是相當重要的議題。
本論文針對交流-直流轉換器，提出增加輸出電壓並提高功率轉換效率的方法。在第二章中，提出具有可適性臨界電壓補償的交流-直流轉換器。透過具背景校正能力的補償電壓，抵消交流-直流轉換器核心電晶體的臨界電壓，提高交流-直流轉換器的輸出電壓，改善功率轉換效率。第三章中，提出具有可適性延遲時間與脈波寬度的交流-直流轉換器。其採用延遲時間與脈波寬度皆可調整的脈波，對交流-直流轉換器內的功率電晶體進行開啟與關閉，增加交流-直流轉換器的輸出電壓，提高功率轉換效率。最後，總結於第四章。

關鍵字

可適性交流-直流轉換器

並列摘要

For the development of the Internet of Things (IoT), wearable devices, and implantable medical devices, the wireless power transmission is receiving significant attention. In these applications, the external power from a transmitter is transmitted by the coils / antennas, and an AC voltage will be received in a wireless device. To convert the AC voltage into a DC one for the device working, an AC-DC converter is widely adopted. The cores of the AC-DC converters usually use a diode-connected MOS transistor or a comparator-based active diode. However, the diode-connected MOS transistor and the active diode suffer from the threshold voltage of a transistor and the turn on/off delay time of the comparator, respectively. Both of them reduce the output voltage and the power conversion efficiency (PCE) of the AC-DC converters. Hence, increasing the output voltage and the PCE are the crucial topics for the AC-DC converters.
This thesis presents two AC-DC converters to increase their output voltages and PCEs. In chapter 2, an AC-DC converter with adaptive threshold voltage compensation is presented. A compensation voltage is adjusted in the background to compensate the threshold voltage of the transistors. The output voltage and the PCE of the AC-DC converter are increased. In chapter 3, an AC-DC converter using an adaptive pulse controller is presented to receive the low input amplitude. The adaptive pulse controller adjusts the delay time and pulse-width of the pulses in the background to turn on/off the power switches. The output voltage is kept as high as possible, and the PCE of this AC-DC converter is enhanced. Finally, the conclusions are given in chapter 4.

並列關鍵字

Adaptive AC-DC Converter

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