本論文提出應用於資料中心48 V電壓調節模組的48 V- 6 V非隔離直流-直流轉換器，此電路架構的優勢為全範圍零切，所有功率開關皆可達到零電壓切換的非隔離型架構，並且藉由變壓器低圈數比2: 2: 1: 1達到8:1的高電壓轉換比。此架構在正半週及負半週時感應側的繞組皆有電流通過，可最大化利用變壓器的繞組。本文探討混合式切換式電容轉換器的工作原理，並針對死區時間的開關汲-源極電壓波形進行分析，得到開關零電壓切換的條件。考慮高功率密度的需求，將轉換器的切換頻率設計為1 MHz，可大幅的降低變壓器的體積大小。藉由分析變壓器的繞組排列順序改變磁動勢對繞組的影響，降低變壓器的銅線損失，並且對鐵芯的尺寸進行參數化設計，在鐵芯體積與變壓器總損耗兩者之間進行評估，取得最佳化的變壓器設計點。最後實現輸入電壓48 V、輸出電壓6 V、切換頻率為1 MHz、輸出功率600 W的非隔離型轉換器。

For the data center 48 voltage regulator module, this thesis propos-es a 48 V-6 V non-isolated DC-DC converter. The advantage of this ar-chitecture is zero-voltage switching over the full load range. The non-isolated DC-DC converter with all the switches can achieve zero voltage switching, and achieve the high voltage conversion ratio of 8:1 by the low turn ratio of the transformer 2: 2: 1: 1. In this structure, current flows through the winding on the secondary side during the positive half cycle and negative half cycle, which can maximize the use of the secondary winding of the transformer. This paper discussing the opera-tion principle of the hybrid switched capacitor converter, and analyzes the switch drain-source voltage waveform in the dead time, and obtains the conditions for the zero-voltage switching of the power devices. Con-sidering the demand of high-power density design, the switching fre-quency of the converter is designed to be 1 MHz for the lower volume of magnetic component. By analyzing the influence of the winding ar-rangement by the magnetomotive force, to reducing copper loss in transformers. Parameterize the transformer and evaluate between the core volume and the total loss of the transformer, to get the optimized trans-former design point. Finally, a non-isolated resonant converter was achieved with a switching frequency of 1 MHz, an input voltage of 48 V, an output voltage of 6 V, and an output power of 600 W.

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