本論文旨在研究應用於電動車快速充電樁之固態變壓器，固態變壓器由三組電源轉換器模組所組成，前級為升壓式功率因數修正轉換器，用以提升功率因數，後級為半橋LLC串聯諧振轉換器，提供負載所需之電壓，在輸出端有均流控制電路，提升電源轉換器模組間之輸出功率分擔能力，並加入模組啟動電路，利用電流感測器判斷系統總輸出電流值來決定啟動之電源轉換器模組數目，以提升輕載效率。文中探討固態變壓器之電路架構，分析動作原理與設計流程，並且使用SIMPLIS電路模擬軟體進行電路模擬，最後實作固態變壓器，由三組電源轉換器輸入串聯輸出並聯構成，總輸出功率為3 kW，輸出規格為48 V/66 A，經實驗驗證各模組輸出電流之均流誤差率可達2 %以下。在交流輸入電壓300 Vrms下，實測固態變壓器，整體電路最高效率為87.51 %，且在有模組啟動電路的情況下，輕載效率有明顯的提升。

This thesis focus on solid-state transformer for electric vehicle fast charging station. The solid-state transformer consists of three sets of power converter modules. The first stage is a boost power factor correction converter to improve the power factor. The second stage is a half-bridge LLC series resonant converter for providing the required voltage to the load. There is a current sharing control circuit at the output to improve the output power sharing capability among the power converter modules. The module startup circuit is designed. The current sensor is used to measure the total output current value of the system to determine the number of power converter modules to start, thereby improving light load efficiency. Circuit architecture of solid-state transformer is discussed in this thesis. The operation and design processes are analyzed, and SIMPLIS circuit simulation software is used for circuit simulation. Finally, the solid-state transformer is implemented. The solid-state transformer consists of three sets of input-series output-parallel power converter. The total output power is 3 kW, and the output specification is 48 V/66 A. It has been verified by experiments that the current sharing error of each module can be less than 2 %. When the AC input voltage is 300 Vrms, the solid-state transformer is measured. The highest efficiency of the solid-state transformer is 87.51 %. In the case of the module startup circuit, the light load efficiency has been significantly improved.

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