本篇論文內容是利用主動箝位技術來達到柔性切換之順向式轉換器，對於順向式轉換器來說，功率半導體開關在導通及截止期間，由於同時存在高電流及高電壓，因此具有很高的切換損失。通常效率及功率密度的提升也會受到負面影響。為了減少開關的切換損失，於是在順向式轉換器的初級側加裝一諧振電感與箝位電容組成的諧振槽，藉此使主功率開關達到零電壓切換的目的，以減少開關的切換損失來提升效率。
本文章利用狀態空間平均法來描述狀態方程式，並以K因子來設計補償器，使系統的穩定性能大大提高符合需求；最後利用模擬軟體IsSpice來模擬轉換器的動態分析。根據預測的結果製作一台120W箝位電壓的順向式轉換器以驗證先前預測的特性。

This thesis describes application of the active-clamp technique to achieve soft-switching for forward converters. For forward converters, the power switch causes high switching loss as the result of high current and high voltage generated during turn-on and turn-off periods. Generally, high switch loss hinders the improvement of efficiency and power density . In order to reduce switching loss, a resonant inductor is added in the primary side of the forward converter to form a resonant tank with the clamped capacitor. As the result, zero voltage switching (ZVS) for the main power switch can then be achieved to reduce the switching loss.
In this thesis, the state-space averaging technique is used to describe the state equation. K factor is applied to design compensator and to greatly enhance the stability of the system so as to meet the requirements. Finally, IsSpice is conducted to simulate the dynamics of the converter. Based on the simulated result, a 120W forward converter with voltage clamp is built to verify with the theoretical analysis.

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