本論文提出一雙級交錯式三階直流/直流/交流轉換器，由前級三階層交錯式升壓轉換器和後級三階層二極體箝位變頻器組合而成。升壓轉換器使用三階層架構和交錯式技術，與傳統升壓轉換器相比，三階層架構可以減半功率開關的電壓應力，交錯式技術可以減小輸入電流漣波。
三階層二極體箝位變頻器有一缺點，其輸出零相序電流會造成中性點電壓漣波與電壓不平衡，而變頻器的低輸出頻率與較差的功率因數都會造成中性點電壓漣波更嚴重，本文利用三階層交錯式升壓轉換器之控制策略改善此現象，使用的控制策略為增減開關之責任週期與前饋控制法，並利用模擬結果比較兩方法的補償效果。
系統使用德州儀器產生的數位訊號處理器(TMS320F28069)作為數位控制核心，本研究建立一個輸入電壓為310 V至530 V，直流鏈電壓控制在750 V的2kW系統，並藉由模擬與實際量測，驗證本論文所提出之方法可行性。

This thesis proposes a two-stage interleaved three-level DC/DC/AC converter, which consists a three-level interleaved dc/dc boost converter in the first stage, and a three-level neutral-point-clamped (NPC) inverter in the second stage. The boost converter uses three level interleaved topology. The three level topology can reduce the power switches voltage stress compare with traditional boost converter. And interleaving technology can reduce the input current ripple.
The drawback of NPC inverter, unbalanced neutral point voltage caused by the zero-sequence components, and compensated by the first stage. Both lower output frequency and poor power factor load of NPC inverter cause the neutral point voltage ripple lager. Use the feedforward control and adjusting duty control to compare the compensated simulation results.
The system adopts the digital signal processor TMS320F28069 as the digital controller. Moreover, this study establishes a 2kW test bench in which the input voltage varies from 310 V to 530 V and dc link is regulated at 750 V. Both simulation and measured results demonstrate the validity of the proposed method.

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