返馳式電源轉換器之一次側精準過載保護控制方法

A Novel High-Precision Primary-Side Controlled Over-Load Protection Scheme for Flyback Converters

黃培倫(Pei-Lun Huang)

指導教授 ： 陳德玉

國立臺灣大學/電機資訊學院/電機工程學研究所/博士(2011年)

https://doi.org/10.6342/NTU.2011.00811

摘要

初級側控制的全電壓輸入型馳返式電源供應器因其成本低及待機功耗低，所以被廣泛應用在現今低瓦數(<120W)電子產品上。最近幾年來，因效率以及待機功耗的法規制定，馳返式電源供應器的研究再度受到重視。
傳統的馳返式電源供應器精準過載保護需要配合二次側恆壓恆流IC，但因成本考量及待機功耗限制，這樣的方法現今已大量被初級側過載保護取代。但初級側過載保護並無法達到準確的要求，所以，本論文提出一個全新的控制架構，透過對開關電流波形的偵測，並加以運算來大幅改善過載保護的精準度，但同時又不需額外增加IC腳位。
模擬和實際IC均通過實驗測試，證實這是一個可行的有效辦法。傳統因過載的不準確造成的功率元件超限設計問題，亦可因此得到改善。以往設計過程耗時耗力的調整也得以由查表而大幅簡化。

關鍵字

馳返式電源供應器 ； 初級側 ； 過載保護

並列摘要

A primary-side controlled universal-line Flyback converter is widely used in many low power applications (<120W) due to its simplicity, low-cost and low standby power advantages. In recent years, this configuration has received renewed attention because of new mandate on light load efficiency and low standby loss. However, conventional over-load protection schemes with primary-side control often experience inaccurate over-load protection.
In this dissertation, a novel scheme is proposed to significantly improve its over-load accuracy. This scheme is implemented in an Integrated Circuit (IC). The proposed scheme is verified with simulations and experiments. Furthermore, this scheme is accomplished without adding extra IC pin compared with conventional schemes. This new IC controller significantly reduces the power stage component size normally reserved for over-load protection inaccuracy.

並列關鍵字

Flyback power converter ； primary side ； over-load protection

參考文獻

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