本論文旨在開發一音響用切換式D類音頻放大器及從事其強健波形追控。為利於從事所研擬之研究，首先探究體會一些基本實務，包含揚聲器之結構與其等效電路模型、D類放大器之電力電路及控制策略、及音響系統之關鍵規格。另外，一些市售之D類放大器亦予以探究，以了解其組成特徵及功能。
其次，設計建構一脈寬調制單相全橋式變頻器，藉由適當之電力電路及切換機構，使其可成功地操作於300kHz之切換頻率，而適用於音頻切換式放大器。基於此，本文提出一雙可調度強健電壓波形控制機構，由迴授控制器、命令前向控制器及強健擾動消除前向控制器組成，經由所提之設計步驟，可使音頻放大器具有緊密且強健之寬廣頻率範圍任意波形追控特性。在所建音頻放大器之性能評估性上，先以電阻性負載從事開發階段測試，再以揚聲器為其實際測試負載。而激勵信號於20Hz至20kHz頻帶間依序採用定頻弦波、帶通濾波之隨機雜訊、音樂光碟所生之實際音源等。
為使所開發之音響系統具有良好之交流入電電力品質，本論文設計製作一反馳式切換式整流器，做為此音響系統之前級轉換器。在不連續電流操作下，經由所提之強健電壓控制，可建立穩定直流鏈電壓且具高入電電力品質。最後，以一些實測結果驗證所建具切換式整流器前級D類放大器供電音響系統之整體操作效能。

The major purposes of this thesis are to develop a switch-mode class-D power amplifier for audio system and to perform its robust waveform control. First, some basic issues are explored for facilitating the system development, these issues include structure and modeling of loudspeaker, power circuits and control schemes of class-D amplifiers, key specifications of audio system, etc. In addition, some existing commercialized class-D amplifiers are surveyed to understand their progress.
Next, a switch mode pulse-width modulated inverter is designed and implemented. The power circuit and switching scheme are properly designed to let the inverter be successfully operated under switching frequency of 300kHz. Then a robust two-degree-of-freedom control (2DOFC) scheme is proposed to let the inverter-fed loudspeaker possesses close and robust voltage arbitrary waveform tracking within wide frequency range. The proposed 2DOFC scheme consists of a feedback controller, a command feedforward controller and a robust disturbance cancellation feedforward controller. Performance evaluation for the developed class-D amplifier is conducted under resistive load and physical loudspeaker load. The waveform tracking control performance is first verified experimentally at some fixed frequencies between 20Hz to 20kHz. Then further evaluations are made using the band-pass filtered random signal and the physical music signal generated from CD player.
Finally, to let the developed audio system have satisfactory line drawn input power quality, a flyback switch mode rectifier (SMR) is designed and implemented. Under discontinuous current mode operation, a robust voltage controller is proposed to establish well-regulated DC-link voltage with high input drawn power quality. Some simulated and experimental results are provided to demonstrate the performance of the whole SMR-fed switch-mode audio system.

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