交錯式主動箝位返馳式轉換器架構具有高效能和高功率的特點，適用於150 W以上具電氣隔離的直流-直流轉換器需求。然而，此種架構在輕負載區段容易產生震盪波形以及呈現低效率。本論文基於交錯式主動箝位返馳式轉換器的拓樸提出改良設計和控制方法，期提升轉換器在輕載的效率以及避免波形震盪。本論文首先介紹交錯式主動箝位返馳式轉換器由二顆並聯功率開關以及二組變壓器、整流器所組成，能夠有效地分擔輸出功率，減小元件尺寸並提高能量轉換效率。其次詳細描述了交錯式主動箝位返馳式轉換器的控制策略，其控制策略採用突衝模式結合脈衝寬度調變技術，確保轉換器的輸出電壓、電流的精確控制，同時實現電壓的主動箝位，減小開關元件的切換損耗，提高轉換器的效率。最後透過模擬和實驗驗證該轉換器有效解決輕負載硬切換導致效率不佳的問題，且在不同負載條件下均實現良好的效率。

The interleaved active clamp flyback converter is a high-efficiency and high-power output architecture suitable for DC-DC converters that need electrical isolation above 150 W. However, this design may experience oscillating waveforms and low efficiency at light loads. To address these issues, this thesis proposes circuit modifications and a control method based on the topology of the interleaved active clamp flyback converter. These modifications aim to enhance efficiency under light loads while also preventing waveform oscillation.
This thesis discusses the structure and working principle of an interleaved active clamp flyback converter. The converter consists of two parallel power switches, two sets of transformers, and rectifiers. This design enables efficient power sharing, smaller component size, and improved energy conversion efficiency. The control strategy is described in detail using burst mode combined with pulse width modulation technology. This approach allows for precise control over output voltage and current while actively clamping voltage to reduce switching losses and enhance overall efficiency. Simulation and experimentation confirm that this converter effectively addresses the problem of poor efficiency caused by light load hard switching. Furthermore, it performs well under varying load conditions.

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