本論文討論三種具代表性的緩振器，其中包含R-C、R-C-D及L-C-D緩振器。R-C緩振器以與電路之漏感形成之R-L-C電路消除電源供應設備電壓波形之過電壓及振鈴波，以抑制振鈴頻率之電磁干擾，屬於損耗性緩振器；R-C-D緩振器呈現電容特性以延緩電源供應設備電壓波形之上升時間，以抑制電源調節時電壓變化之波形上升時間改變所產生之電磁干擾，屬於損耗性緩振器，也是極性緩振器；L-C-D緩振器以電感器及共振電路延緩電源供應設備電流波形之上升時間，並以電容器延緩電壓波形之上升時間，屬於非損耗性緩振器，適用於抑制電源調節時電壓及電流變化之波形上升時間改變所產生之電磁干擾。本論文對R-C緩振器的研究，適用於所有形式之轉換器，對於振鈴波之抑制；R-C-D緩振器之研究，適用於所有形式之轉換器對於電壓波形的改變；L-C-D緩振器的研究適用於升壓型及降壓型轉換器對於電流及電壓波形的改變。上列三種緩振器分別使用於功率校正轉換器、順向轉換器及返馳轉換器等架構，藉由數學式之分析及模擬，以得到緩振器唯一的相關性，包含波形比較與頻譜分佈。本論文以實驗驗證此三種緩振器分別使用於功率校正轉換器、順向轉換器及返馳轉換器等架構，所獲得的結果非常接近理論預測。

In this thesis, three kinds of representative snubbers are discussed, including R-C, R-C-D and L-C-D snubbers, respectively. R-C snubber, a dissipative snubber, associating with circuit leakage inductance is to form a R-L-C circuit to eliminate overvoltage and ring wave around the power device so as to suppress ring wave EMI. R-C-D snubber, a dissipative and polarized snubber, acts as a capacitor to prolong the rise time of voltage waveform around the power switch so as to suppress EMI resulted from rise time changed by voltage variation in power regulation. The last L-C-D snubber, a lossless snubber, uses inductor and resonant circuit to prolong rise time of current waveform around the power device, in which the capacitor is used to prolong rise time of the voltage waveform. It is appropriate for suppressing EMI resulted from rise time changed by voltage and current variations in power regulation. The investigation for R-C snubber is appropriate for all kinds of converters about ring wave suppression. R-C-D snubber is appropriate for all kinds of converters about voltage rise time change. L-C-D snubber is appropriate for buck and boost converters about rise time changes of current and voltage. Three kinds of snubbers are respectively applied in PFC, forward and flyback converter topologies by way of mathematics analysis and simulation for achieving a unified relationship between the mentioned snubbers, including waveform comparison and spectrum distribution. In this thesis, experiments for the three kinds of snubber circuits applied in PFC, forward and flyback converters are examined. Their performances are quite close to the theoretical predictions.

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