本論文提出新型之線圈設計應用於生醫植入裝置於無線傳能(Wireless Power Transfer, WPT)系統傳輸效率。應用於生醫植入環境下之傳能系統受限於小空間之傳能線圈導致低傳輸效率，本研究提出提高小型化線圈最大效率之設計，並結合前端功率放大電路特性進行系統優化，藉探究微型化無線傳能線圈之基礎理論，建立設計與優化之準則。本論文提出即使在有限之植入空間，仍可藉著多層立體之空間達到更高自由度和最佳化，配合FR4版雙層設計來實現，並藉此微完成高Q值、高耦合係數植入式線圈設計，提高小植入面積下之傳輸效率。研究結合了無線傳能技術與生醫應用領域應用，開發操作於13.56 MHz頻帶的一微型化植入式線圈，並且完成整合即時資料偵測與電刺激系統。研究中包括線圈特性探討、微小化線圈設計、四線圈傳能系統(4-coil WPT)、雙層線圈技術、系統整合之技術開發，提高植入式線圈效率研究與降低生醫植入式環境的影響，且設計前端高效率Class-E功率放大器來達到後端能量的需求。
在實驗過程中，所實現的最佳4-Coil WPT線圈系統，植入線圈面積為25 mm2，在生物組織環境距離10毫米下量測PTE效率為11.7%，相較於傳統二線圈無線傳能系統提升了5.1倍，成功提升了植入線圈組織中之無線傳能效率。經由FOM所算為94，為所比較文獻中最高。本系統先經由高效率的四線圈無線傳能系統發射1瓦的功率，成功進行低功率整合深腦刺激(Deep Brain Stimulation, DBS)系統驗證，供應微晶片、藍芽傳輸、與最大電流為180微安之電刺激等電路。本篇論文不僅是設計植入式線圈，對微波通訊上，基板的空間高自由度、低成本、低重量等，其優越的高效率與無線傳能之便利性將成為未來的科技趨勢。

This thesis presents a novel coil design to improve the efficiency of the wireless energy transfer (WPT) system applying in biomedical implantable devices. Due to the limited space in biomedical implantable applications, the transmission efficiency drops significantly. This study proposed a high efficient compact coil design, combining with the front-end power amplifier for system optimization. The fundamental theories of miniaturized WPT coil parameters were studied for the for the design and optimization. Even under the very limited space, this thesis proposes the multi-layer 3D design to achieve higher degree of freedom design and WPT system optimization. The proposed system can be simply implemented with double-layer FR4 substrate and achieves a high WPT efficiency under a small implant area.
This study integrates a WPT technologies and biomedical applications. Miniaturized implantable coils were developed to operate at 13.56 MHz. Moreover, and functional electrical stimulation (FES) systems were integrated as a whole deep brain stimulation (DBS) test system. This thesis includes investigation of the WPT coil, the miniaturization design, four-coil WPT, dual-layer coil technology, and the whole system integration. The proposed system improves the power transfer efficiency (PTE) of the implantable coil system and mitigates the implantable environment influences on power deliver. Design of the high efficient Class-E power amplifier to achieve the power demand for the DBS. The main objective is to integrate the proposed WPT systems with an implantable FES system. The fundamental equations for WPT were analyzed to assist and verify the design.
During the experiment, the distance between transmitting coil and receiving coil is standardized as a common baseline for comparison. The optimal 4-Coil WPT coil system was fabricated with a implanted coil area of 25 mm2. At a distance of 10 mm in biological tissue environments, the PTE was measured to 11.7%, which was improved by 5.1 times compared to the traditional two-coil WPT system. The PTE using a small coil through tissue was successfully and significantly enhanced. Finally, Figure-of-Merit (FOM) is 94, FOM is defined and the proposed system has the optimal efficiency. By using this high efficient four-coil WPT system, 100-mW power amplifier successfully supply the power for the integration of low-power DBS system, including the micro-processor, the Bluetooth transmission, and FES with a maximum current of 180 μA. This thesis provides the outstanding design of the 2-layer coil not only for implantable devices, but also for microwave or commercial communications. Such a high degree of freedom WPT coil design in a low cost, low weight substrate can be applied widespread fields.

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