具低開關跨壓之多相升壓型直流轉換器建模與控制

Modeling and Control of a Multi-Phase Step-Up DC/DC Converter with Low Switch Voltage Stress

許嵐婷(Lan-Ting Hsu)

指導教授 ： 潘晴財

國立清華大學/電機資訊學院/電機工程學系/碩士(2008年)

https://doi.org/10.6843/NTHU.2008.00716

摘要

近年來隨著油價高漲與環保之重視，使得世界各國均積極推動再生能源與潔淨能源的開發，而其中光伏電池與燃料電池亦扮演一甚為重要的角色；然而這兩類電源之輸出電壓較低，因此需要依高升壓比之電源轉換器，作為此二類新能源系統之介面，將其提升至較高電壓以作為後級應用。因此本文之重點，即在研發一高升壓比高效率直流轉換器，以作為此兩類電源系統之應用。
本論文的主要貢獻有三點。文中首先針對高升壓比及高效率之目標，提出一新型多相升壓型直流轉換器，新型轉換器可以有效地降低主動開關之耐壓與輸出電壓漣波，並可於較寬廣的負載變動範圍維持高效率。第二點貢獻則是針對新型轉換器進一步推導出其小信號數學模型，以作為閉迴路控制器設計之依據，使得轉換器擁有較好的穩定性及暫態響應特性。第三點貢獻則依據理論分析的結果實際製作一輸入電壓24V、輸出電壓200V以及輸出功率100W之雛型系統以驗證新型轉換器的可行性。電路模擬與實測結果顯示本論文所研製之新型轉換器，其電源轉換效率於40W至100W的負載情況下均為93%以上，最高可達到94%，而其主動開關跨壓與輸出電壓漣波比較2007年提出的一新型倍壓式轉換器，可分別降低25%及16.7%。

關鍵字

分散式能源 ； 再生能源 ； 高升壓比直流轉換器 ； 低開關跨壓 ； 建模與控制

並列摘要

In recent years, with global energy shortage and strong environmental movements, many countries are encouraging and promoting the development of distributed energy sources such as fuel cells and renewable energies. As important roles in new energy, however, the output voltage of the solar cells and the fuel cells is rather low. Hence, a high step-up dc/dc converter is normally required as an interface to increase voltage for back-end applications. Therefore, emphasis of this thesis is placed on developing a high efficiency and high step-up dc/dc converter for these two new energy systems.
Basically, the main contributions of this thesis can be summarized as follows. First, a new high efficiency and high step-up dc/dc converter is proposed. It can effectively reduce the voltage stress of active switches and the output voltage ripple of the converter. Moreover, it is able to maintain rather high efficiency in wide load range. Second, the mathematical model of the proposed converter is derived. According to the model, a close-loop controller is designed to achieve better stability and transient response of the converter. Finally, a 200V/100W laboratory prototype is constructed and corresponding simulations as well as experimental results are provided to verify the feasibility of the proposed converter. It is seen that the resulting efficiency curve can be maintained rather flat and above 93% for a load varied from 40W to 100W. Furthermore, the voltage stress of active switches and the output voltage ripple are 25% and 16.7%, respectively, lower than that of the voltage doubler proposed in 2007.

並列關鍵字

Distributed Source ； Renewable Energy ； High Step-Up Converter ； Low Switch Voltage Stress ； Modeling and Control

參考文獻

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