本論文提出一新型之自動平衡單相九階層耦合電感器式換流器，透過輸入電容器之串聯儲能與串、並聯釋能實現電容電壓自動平衡。本架構使用2個輸入電容器、10個功率開關、3個功率二極體與1個耦合電感器實現九階層之電壓輸出。本架構與相同階層數的傳統架構比，使用了較少的元件，且無須額外的電容平衡電路以及複雜的控制法，因此具有高功率密度、電路體積小與低成本等優點，並能有效降低輸出電壓總諧波失真率。論文中將說明電路之動作原理與控制方法，並設計一輸入為直流電壓270 V、輸出功率為4 kW實體電路，驗證本文所提出理論之正確性與可行性，效率在3.28 kW可達94.6%。

In this thesis, a novel self-balancing single-phase nine-level inverter with coupled inductor is proposed. The proposed inverter achieves auto voltage balance by using the path of series charged and series or parallel discharged. The topology of the proposed structure constructed of two input capacitors, ten power switches, three power diodes and one coupled inductor. Compared with the same level conventional inverter topologies, the proposed nine-level inverter has less components and easy control method without added voltage balance circuit. So, the higher power density, smaller size, lower cost and low total output voltage harmonic distortion of circuit can be realized.
Finally, the details of modes analysis and control methods are discussed. And, a 4 kW laboratory prototype inverter with input voltage 270 Vdc is proposed to verify the theoretical analysis and the performance of the proposed circuit. The efficiency achieves 94.6% at output power of 3.29 kW

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