本文以數位控制方式實現一台三相換流器系統，一般高頻閉迴路控制會受限於數位晶片計算時間壓縮問題，須採取多次切換週期才觸發一次中斷事件，將造成責任週期於數個週期後才可更新一次，在換流器的應用下，責任週期必須隨著輸出交流電壓時變，否則將導致電壓諧波失真增加。因此本文提出新型的控制方式，在一個中斷事件下，閉迴路系統與空間向量脈波寬度調變得到目前狀態訊號。同時，電流預測控制可得出下一態的切換信號，並透過或閘元件結合，達成倍頻以及降低電壓諧波失真的效果。硬體架構方面，採用三相全橋式拓樸實現。功率開關元件選用氮化鎵作為半導體材料，寬能隙以及高電子遷移率的特性使開關元件更適合操作在高頻與高功率的情況。
經過嚴謹的設計與損耗分析後，研製出操作頻率200 kHz，輸入直流電壓360 V~400 V，輸出交流電壓220 Vac，輸出功率3300 W之預測控制結合空間向量脈波寬度調變三相全橋換流器。實作證明，本文控制技術對比傳統控制法在三相電壓諧波失真皆可達到改善的效果。

This thesis uses digital controller to implement three-phase inverter. Generally, high-frequency control is limited by the processing time and force interrupt event be triggered by several switching cycles, resulting in duty cycle can’t be updated immediately. In the application of the inverter, it will cause voltage harmonic distortion. Therefore, new control method is proposed. In an interrupt event, SVPWM combine with prediction control will get current state signal and next state signal, through the OR gate element can add them to achieve the effect of frequency doubling and low voltage harmonics. Topology uses a Three-Phase Full-Bridge architecture. GaN devices are used as the power switches. The wide energy gap and high electron mobility characteristics make the switch more suitable for operating at high frequencies and high power.
After rigorous design and loss analysis, Three-Phase Full-Bridge Inverter Using Space Vector Pulse Width Modulation Combine with Prediction Control is implemented. Operating frequency is 200 kHz, input DC voltage is 360 V~400 V, output AC voltage is 220 Vac, and output power is 3300 W. It has been proved that the control strategy in this thesis can improve the three-phase voltage harmonic distortion in comparison with the traditional control method.

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