本文提出具有低輸入電流漣波之雙開關順向轉換器電路(2SFRR)。此電路是由傳統雙開關順向轉換器(2SFC)所延伸出來，傳統雙開關轉換器因開關的動作為不連續的，導致輸入電流也不連續，故會產生高的輸入電流漣波和電磁干擾(EMI)。主要是在傳統雙開關轉換器一次側的兩顆箝位二極體和兩顆開關MOS中間加上一顆箝位電容，籍由箝位電容以及變壓器的漏感可以達成輸入電流漣波的降低，應用於高電壓開關單元提升轉換器的效率。除了電路工作原理之介紹，並以輸入範圍300-400V和50V/5A輸出，開關的切換頻率為100 kHz的電路規格進行實驗與驗證。

Two-switch forward converter with current ripple reduction (2SFRR) is proposed and investigated in this thesis. Due to its low voltage stress on power devices, the proposed converter is suitable for high frequency high input voltage low-to-medium power conversion applications.
The proposed converter is derived from a two-switch forward converter (2SFC) by inserting a clamping capacitor between two identical primary windings and modifying with two series-connected MOSFETs and diodes. Lossless snubbing, voltage sharing, voltage clamping and input current ripple reduction features are obtained under steady-state and transient conditions.
By utilizing the clamp capacitor and the leakage inductances of the transformer, moreover, there is an input current ripple reduction property. As a result,, the EMI di/dt noise caused by the pulsating input current can be reduced.
To demonstrate its feasibility, the operation principle as well as the experimental results with 100 kHz, 300-400V input source and 50V/5A output power are described in this thesis.

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