本論文旨在實現無指向性無線電能傳輸能力於空間自由定位充電，研製無指向性無線電能傳輸系統，提供該空間環形區域內行動裝置無線充電。為了達到無指向性無線傳能之能力，本文Tx線圈由兩個彼此正交菱形線圈組成，並利用單晶片微處理器實現電流相位控制，使周圍磁場向量化時多工，隨時間改變磁場向量方向進行360度旋轉，形成圓形磁場軌跡，整體系統採用三線圈耦合架構，以共振線圈來提升其輻射磁場強度，使多個Rx線圈有效接收能量。文中透過數學建模與電磁學理論，了解Tx線圈周圍磁場分布，並討論Tx線圈彼此間互感關係，藉由磁場模擬軟體協助分析其磁場空間分布。最後經由實驗測量得知，本文所研製之多負載於空間自由充電之無指向性無線電能傳輸系統，產生全方位的磁場分布，並在間距32公分對空間環形區域內多個負載進行無線傳能，多負載整體傳輸效率高達25%。

This thesis is aimed to realize the omnidirectional wireless power transfer capability of spatial free-positioning charging. The omnidirectional wireless power transfer system is developed to provide power for mobile devices in the spatial torus area. To implement omnidirectional power transfer capability, Tx coils are comprised of two orthogonal rhombic coils and utilize microprocessor to achieve the current phase control method. This manner changes the direction of the magnetic vector over time to rotate 360 degrees, forming a circular magnetic field trajectory. The overall system adopts a three-coil coupled structure, which utilizes a resonant coil to enhance radiation magnetic field strength so that multiple Rx coils receive energy efficiently. The thesis uses mathematical modeling and electromagnetic theory to understand the distribution of magnetic field around Tx coils, discusses the mutual inductance relationship between Tx coils, and analyzes the distribution of magnetic field through magnetic field simulation software. Eventually, experimental results show that omnidirectional system proposed in this thesis can produce omnidirectional distribution of magnetic field and conduct wireless power transmission to multiple loads devices in the spatial torus area at a distance of 32 cm. Overall efficiency for multiple Rx coils meets 25%.

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