本研究旨在設計與研製一套具備擴增升降壓範圍與優異電壓變動承受能力之固態變壓器系統，以提升多元應用場景下的適應性。本系統架構採用升降壓轉換器作為前級，透過調變工作週期實現輸入電壓在寬範圍內之動態調節，確保輸出穩定，且為提升功率密度並減少體積，系統中選用薄膜電容取代電解電容，以有效減少系統體積，同時本系統電路的中間級採用LLC諧振轉換器作為隔離電路，透過參數設計以實現負載獨立的定電壓輸出，然後在控制方面則透過回授控制進行調整功率開關時序，以實現穩壓功能。本文並且建構原型電路，以及進行不同輸入電壓與負載條件之測試，實驗波形驗證即使輸入電壓出現顯著變化情形時，本設計電路輸出端均能保持穩定，驗證本系統於擴增升降壓範圍時，具備優異的電壓調適能力，研究成果對於需具彈性調節需求之固態變壓器設計，具有參考價值。

This study aims to design and develop a solid-state transformer system considering an expanded voltage conversion range and enhanced voltage fluctuation tolerance, enhancing adaptability across diverse application scenarios. The system architecture adopts a buck-boost converter as the front-end stage, enabling dynamic input voltage regulation over a wide range through duty cycle modulation to ensure stable output. To improve power density and reduce system size, thin-film capacitors are used in place of electrolytic capacitors. Furthermore, the system incorporates an LLC resonant converter in the intermediate stage as the isolation circuit, which is designed to achieve load-independent constant voltage output through appropriate parameter selection. In terms of control, feedback regulation is also used to adjust the timing of the power switches, thereby achieving voltage stabilization. A prototype circuit is constructed, and tests are conducted under various input voltage and load conditions. Experimental waveforms confirm that the circuit output remains stable even under significant input voltage variations, validating the voltage adaptation capability across an extended buck-boost range. The results of this study provide valuable reference for the design of solid-state transformers requiring flexible voltage regulation.

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