本論文主要是利用Simplis模擬軟體來探討差頻對直流降壓轉換器的影響，探討的範圍包含差頻對單相電壓模式、峰值電流模式及雙相雙迴路模式降壓轉換器的影響，了解兩種模式之優缺點及各個模式對於差頻之處理方式。模擬在直流降壓轉換器的基本架構電路上，嘗試以單相電壓模式、峰值電流模式等不同控制。在模擬中，探討當差頻發生時，在不同控制模式下，輸出電壓及電感電流的變化。且在雙相直流降壓轉換器應用電路模擬中，探討當差頻發生時，為何各相電感電流變化幅度遠大於輸出電壓，及為何雙相與單相直流降壓轉換器的結果會不同。
在本文中，也藉由Simplis模擬軟體中所提供之雙相直流降壓轉換器應用電路，經由模擬之波形來解釋在不同的差頻負載下，輸出電壓及電感電流波形之相對應的變化，了解影響輸出電感電流變化之最大因素。在最後，會探討幾種可能的解決方案及其改善效果。同時，也針對目前之結果，提出建議方案及未來研究之目標。

In this thesis, the effect of beat frequency on DC-DC buck converters is discussed by using Simplis simulation software. This study covers the effect of the beat frequency on the single-phase voltage mode and peak current mode and the two-phase dual-loop control mode. The advantages and disadvantages of these two control modes and how these two control modes deal with the loading with beat frequency are also covered.
In the simulation, the behaviors of output voltage and current under beat frequency is discussed. In the simulation with the two-phase the DC buck converter, why the amplitude of the inductor current is much bigger than the output voltage’s under beat frequency is discussed. The discussion also explains why the behaviors under beat frequency condition are different among the voltage mode、peak current mode single phase buck converters and two phase dual-loop buck converters.
In the end of this thesis, some solutions are discussed. The proposed solution and the future research objectives are also disclosed.

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