本論文主旨為研究換流器系統之隔離式直流-直流升壓轉換器應用，選用架構為電流饋入式雙主動橋式轉換器，以實現高功率高效率且符合換流器系統應用為目標進行研究。內文除了分析電流饋入式雙主動橋式轉換器之工作原理及開關電壓突波抑制調變，更進一步探討在換流器系統應用之隔離式升壓轉換器。因應此架構為隔離式升壓轉換器，無法採用傳統冷啟動方式對輸出濾波電容充電來避免湧浪電流產生，將以隔離式輔助電源先對輸出濾波電容充電，達到避免電路啟動瞬間湧浪電流產生。而本文提出之架構及控制法需適用於換流器系統，故針對換流器產生之二次諧波電流，將透過加入虛擬電阻與帶拒濾波器達成補償效果。本文在閉迴路控制系統中，全權由數位控制器達成電路啟動、開關電壓突波抑制調變、二次諧波電流抑制及保護等控制。
最後實作出一台具輸出功率3 kW，輸入電壓為36 V至58 V、輸出電壓為400 V之轉換器，效率最高可達97%。

This thesis is to study the current-fed dual-active bridge converter, a high power and high efficiency isolated DC-DC boost converter for inverter system applications. First, the operating principles and design consideration of the topology are analyzed. Second, the output capacitor will be charged with the isolated auxiliary power supply to avoid the inrush current when the circuit starts. Third, this thesis proposes that the control method reduce the second harmonic current which from the downstream inverter by adding a virtual resistor and a notch filter. In the closed-loop control system, the digital controller achieves the control of the system start-up, pre-charge modulation, second harmonic current reduction.
　　Finally, a 3 kW isolated DC-DC boost converter is implemented. The input voltage is from 36 V to 58 V, the output voltage is 400 V and the efficiency achieve 97%.

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