隨著科技的發展與電氣設備的普及化，使得生活環境中電磁場的曝露範圍更加廣佈。迄今，雖尚無電磁場的相關研究報告明確指出，電磁場確實對生物體有特定的危害，但是對於磁場造成生物體影響的研究仍持續地在進行，目前大多數的研究報告都建議生物體盡量遠離電磁場源，以預防曝露於電磁場中可能造成的各種危害，但大多數僅針對於低頻交流設備；而在目前高頻設備的廣泛使用之下，生物體在高頻磁場源中的曝露次數更加頻繁，鑑此，本文研究重點著重在設計一產生高頻磁場的電源供應器，以利於相關研究可進行各種高頻電磁場的實驗。因此，本論文的主要目標在設計一個高頻磁場電源供應器，可將切換頻率提高至125KHz，對整個電源供應器而言可以提高效率和減少體積，並使用零電壓切換相移式脈波寬度調變技術，降低功率開關元件之切換損失、切換應力及電磁干擾。為了能夠調整輸出功率及切換頻率，乃藉由FPGA嵌入式晶片與VHDL硬體描述語言設計一控制晶片，來產生數位脈波訊號，達成數位式相移脈波寬度調變控制的技術，進而改變輸出電壓的工作週期和頻率的控制。最後，利用Is-Spice電子電路軟體進行實際的模擬及探討，並驗證高頻數位脈波訊號的產生及零電壓切換技術。 With the progressing of science and the popularization of electric equipments, exposed to electric magnetic field environment is increased. Although no reports have indicated that the specific electric magnetic field is danger to the living organism, the research of magnetic field’s influence on organism are also continued. Most research papers proposed that the organism should maintain a distance from the electric magnetic field in order to prevent various kinds of danger that may be caused from exposure. However, those reports mainly focused on exposure from low frequency alternating current equipment. At present, high-frequency equipments are widely used and the exposure to the high-frequency magnetic field of organism is more frequent. For this reason, this thesis emphasizes a high-frequency magnetic field environment to best conduct experiments of conclusive nature. The main goal of this thesis is to design a high-frequency power supply device to provide the magnetic field. The frequency of the high-frequency power supply is up to 125KHz to raise the efficiency and reduce the volume. By using the phase-shifted full-bridge zero-voltage-switched PWM technique, this design can reduce switching loss, component stress, and electromagnetic interferences of power semiconductor devices. In order to adjust the output power and switching frequency exactly, this thesis uses the digital pulse signals by FPGA embedded chip and VHDL to change the work period of the output voltage and control frequency. Finally, this study used Is-Spice electronic circuit software to conduct real simulation and discussion, and proved the production of high-frequency pulse signals and ZVS technique.
