近年來，中高壓固態變壓器逐漸發展於智慧微電網、風能系統及牽引力系統。相較於傳統50 /60 Hz之配電變壓器，中壓固態變壓器將操作頻率提升，使其磁性元件之體積與重量縮小。中高壓固態變壓器受到功率半導體元件之限制，使其中DC/DC轉換器需選擇輸入串聯輸出並聯拓撲，但模組中元件參數會含有誤差量，造成模組功率不平衡，使元件損壞或衍生散熱問題。因此，本論文主要探討輸入串聯輸出並聯直流/直流轉換器模組功率不平衡之原因，並且提出了輸入電壓與輸出電流之平衡關係式。本文利用軟體SIMPLIS ®模擬與驗證提出關係式之可行性。
最後，本文研製一輸入串聯輸出並聯諧振式直流/直流轉換器之雛形電路，其輸入電壓3.04 kV、輸出電壓380 V及輸出功率9.5 kW，驗證本文所提出關係式之可行性。

In recent years, medium-voltage solid-state transformers (SST) have gradually developed into smart micro-grid, wind energy system and traction system. Compared with the line frequency distribution transformer, medium-voltage SST increases the operating frequency, which reduces volume and weight of magnetic components. The DC/DC converter of medium-voltage SST is limited by power semiconductor devices. Hence, it must select input-series output-parallel (ISOP) topology. However, the components of deviated parameters for the module cause the module power imbalance, which causes damage to components and more heat dissipation. Therefore, in this thesis, the module power imbalance is studied. The relation of input voltage and output current sharing is proposed in the ISOP DC/DC converter. Moreover, using software of SIMPLIS® simulation to verify the feasibility of the proposed relation.
Finally, the prototype circuit of the ISOP resonant DC/DC converter with input voltage of 3.04 kV, output voltage of 380 V and output power of 9.5 kW is developed to verify the feasibility of the proposed relation.

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