本論文旨在研製一新型具有自動平衡功能之九階層耦合電感式換流器。本架構之主要概念為利用兩顆輸入電容來達到九階層電壓輸出，電容電壓自動平衡是利用兩者串聯儲能以及串並聯釋能來達成。與同樣階層數的架構相比，此架構具有元件較少以及電容電壓平衡之特性，不需要再額外添加平衡電路或者是複雜的控制法，因此具有電路體積小、高功率密度及低成本等優點，並且有效降低輸出電壓總諧波失真率。本論文中將會說明電路之工作原理以及控制方法。控制器採用TMS320F28035數位訊號處理器來實現。最後將研製一輸入直流電壓270 V，輸出電壓380 Vrms，輸出功率為3 kW之實體電路，用以驗證本文所提出理論之正確性與可行性，其滿載效率為95.46%，最大效率於1725 W時可達97.1%。

In this thesis, a novel self-balancing nine-level inverter with coupled inductor is proposed. The proposed inverter can generate nine-level voltage with only two capacitors, and making series charged and series with parallel discharging path to self-balancing. Compared with the same level conventional topologies, this topology uses less components and makes voltage balance without using additional voltage-balancing circuit or complex control method, so its benefits are smaller size circuit, higher power density and lower cost. The total harmonic distortion of the output voltage is low. The control scheme is implemented by TMS320F28035. Finally, a laboratory prototype of nine-level inverter with 270 V input voltage and 380 Vrms/3 kW output is implemented. The efficiency under full load is 95.46%, the maximum efficiency is 97.1% at output power of 1725 W.

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