零電壓切換之準諧振返馳式轉換器分析與設計

Abstract

在隔離型電源轉換器中，返馳式轉換器由於具有電路架構簡單、低成本和較少的元件數目之特性，因此廣泛地使用在低功率電子產品上。而一種可實現柔性切換技術的，即是零電壓切換準諧振返馳式轉換器，它和傳統的返馳式轉換器相比擁有許多優點，但仍保有返馳式轉換器的長處。在本論文中，將詳細探討操作在臨界導通模式之零電壓切換準諧振返馳式轉換器的運作。此外，還提出設計功率級電路和控制迴路的設計步驟。最後，將實作一額定功率為80瓦的零電壓切換準諧振返馳式轉換器來驗證理論的分析。

Of all the isolated power converters, flyback converter is widely used for low power electrical appliances, since its property of the simple circuit topology, low cost, and fewer components. Zero-voltage-switching quasi-resonant flyback converter (ZVSQRC flyback), which is able to realized soft switching technique, has several advantages compared with conventional flyback converter, but it still possesses the merits of flyback converter. In this thesis, the operation of ZVSQRC flyback operated in critical conduction mode is investigated in detail. Besides, the designing procedure including power stage circuit and control loop is proposed. Finally, a ZVSQRC flyback with rated power of 80W is implemented to verify the theoretical analysis.