本論文以數位控制實現雙模式控制三相二極體箝位式換流器，達到提升頻率使電路小型化，並且使用連續導通模式 (Continuous Conduction Mode, CCM)以及三角形電流導通模式 (Triangular Cur-rent Mode, TCM)兩種導通模式改善效率。首先介紹了五種不同架構的換流器，並說明各架構的優缺點，再來介紹四種不同的調變技術，其中包含正弦脈波寬度調變(Sinusoidal PWM, SPWM)、空間向量脈波寬度調變(Space Vector PWM, SVPWM)、載波脈波寬度調變(Carrier-based PWM, CBPWM)和磁滯控制(Hysteresis Control)，以及介紹四種操作模式，其中包含電流臨界模式 (Boundary Conduction Mode, BCM)、連續導通模式、不連續導通模式 (Discontinuous Conduction Mode, DCM)和三角形電流導通模式。為了實現高頻化、小型化且同時改善電路效率，本論文架構採用三階層橋式架構，搭配磁滯控制的方式實現CCM與TCM雙模式控制。其中CCM在輸出電流較高時，有著較低的導通損耗；TCM能夠實現零電壓切換，進而改善零交越處的高頻切換損耗。實現過程中包含架構控制分析、回授控制設計以及雙模式最佳設計與分析，搭配PSIM、Mathcad與MATLAB等模擬軟體做驗證，並使用德州儀器公司(Texas Instruments)所生產的TMS320F280049作為控制器，最終實現一台規格為輸入電壓400 V、輸出線電壓220 VAC、切換頻率50k~200 kHz、功率825 W之具有零電壓切換(Zero Voltage Switching, ZVS)功能的雙模式控制三相二極體箝位式換流器。

This thesis uses the digital controller to design and implement a three-phase Neutral-Point-Clamped inverter with zero-voltage switch-ing(ZVS) control method. Firstly, five different topologies have been introduced and compared its advantage and disadvantage. Secondly, four different modulation techniques including Sinusoidal PWM, Space Vector PWM, Carrier-based PWM, and Hysteresis Control have been analyzed. Thirdly, four different current mode control include Boundary Conduction Mode, Continuous Conduction Mode, Discontinuous Conduction Mode, and Triangular Current Mode are presented. This paper uses three-level structure with Hysteresis Control to achieve both CCM and TCM. CCM is used when a high operating current occurs, it can have lower conduction loss. TCM can achieve ZVS for improving the zero-crossing effect, lowering the switching loss. This paper analyzes the control method, feedback control, and optimize its design under du-al-mode, by using various software, such as PSIM Mathcad and MATLAB to verify the design. In the end, Three phases Neu-tral-Point-Clamped inverter using dual-mode method achieve ze-ro-voltage switching is implemented. Operating frequency is between 50k ~ 200 kHz, input DC voltage is 400 V, output AC voltage is 220 Vac, and output power is 825 W.

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