本論文旨在研製一套輔以主動增益調節機制之三線圈無線電能傳輸系統，此研究乃考量現今電動載具之無線充電常面臨錯位問題，以致於影響傳輸效能，故本文研發設計一套具有主動切換機構之系統，於正對位與錯位情況時可自動選擇運行模式，以使系統具備定電壓輸出特性與良好傳輸效率，同時降低成本與電路體積，確保優良供電品質與應用彈性。本論文之研究進行上，首先分析兩種三線圈架構之諧振等效電路，據以進行模擬分析與特性比較，俟決定符合需求之架構後，提出詳細之參數設計流程，進而制訂回授控制策略，以提高整體系統穩定性。而為驗證本文設計流程與電路規劃適切性，本論文已建置一套切換式三線圈系統之硬體電路，並進行各級電路功能實測，測試結果顯示本系統於各輸出功率及各錯位情況下，負載端均可維持相同輸出電壓，並兼具高傳輸效率，研究成果可作為電動載具與無線電能傳輸開發參考。

This thesis aims to develop a three-coil wireless power transfer system with active gain regulation mechanism. By considering that the problem of misalignment often significantly affects the charging performance, the study is thus devoted to developing a system with active switching mechanism so as to automatically select the operating mode to maintain the constant voltage output as well as satisfactory transmission efficiency. Through this design, the cost and circuit volume can be meanwhile reduced while exhibiting the good quality of supplying-power and demonstrating the flexibility of application. For the goal of this study, the thesis first analyzes the resonant equivalent circuit of two three-coil architectures and compares the characteristics of simulation results. After determine the architecture that meets the requirements, the study goes to propose the detailed flow of parameter design and make the feedback control strategy in order to improve the overall system stability. To verify the effectiveness of the design procedure and circuit planning, this thesis has realized a hardware circuit of the switching three-coil system with measurement of circuit functions. Test results show that the load terminal can maintain the output voltage with high transmission efficiency under each output power condition and each misalignment condition that is concerned. The outcome of this study can be used as beneficial reference for research and development of electric vehicles and wireless power transmission technologies.

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