本論文主旨在於研製一新型自動平衡單相七階層耦合電感式換流器，利用兩顆輸入電容達到七階層電壓輸出，而透過串聯儲能與並聯釋能即可實現電容電壓平衡。與同樣階層數的傳統架構相比，此新架構擁有元件較少以及電容電壓自動平衡之特性，無須添加任何的平衡電路或複雜的控制法，因此具有高功率密度，電路體積小、成本低及低輸出電壓總諧波失真率等優點。文中將說明本電路架構之動作原理及控制流程。最後本文設計一輸入直流電壓360 V及輸出功率3 kW之實作電路，驗證本文所提出之理論正確性與可行性；控制部份是以數位訊號處理器(TMS320F28035)為控制核心。

In this thesis, a novel self-balancing single-phase seven-level inverter with coupled inductor is proposed. The proposed inverter can generate seven-level voltage with only two capacitors, and there are series charged and parallel discharged path to auto balance. Compared with the same level traditional inverter topologies, this new topology uses less components and achieves voltage balance without any voltage-balancing circuit or complex control method, so higher power density and smaller size of circuit can be realized. The total harmonic distortion of the output voltage is low. Finally, a 3 kW laboratory prototype inverter with input voltage 360 V is proposed to verify the theoretical analysis and the performance. The control scheme is implemented by DSP (Digital Signal Processor) TMS320F28035.

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