本文提出新穎之蛇型（彎折）結構線圈設計應用於無線傳能系統以提升水平錯位容忍度，並結合雙電容之拓樸網路達到系統最佳傳能效率之分析。無線傳能領域從小功率之生醫植入應用、消費型電子產品、到大功率之電動車充電系統，提供產品應用之空間自由度且保有高效的傳輸效率是所有無線傳能工程的重大願景，然而在磁偶共振無線傳能中線圈的偏移會對效率造成顯著影響。
本文透過電磁模擬軟體分析提出之平面並聯蛇型線圈(Planar Parallel Serpentine Coil, PPSC)與其結合單環線圈結構之蝴蝶形並聯蛇型線圈(Butterfly-Shape Parallel Serpentine Coil, PBSC)，均勻磁場分布的設計透過水平錯位之偶合衰減驗證，相較於傳統螺旋線圈，本文所提出蛇型線圈結構對於水平錯位容忍度有顯著提升。接著，本文提出雙電容拓樸網路模型之完整推導與對於耦合衰減之特色分析，透過雙電容網路可使兩線圈在最大的自由度且操作在最佳傳能效率的情境，更甚他者在於本文完整考慮包含前級系統隨錯位之整體效率衰減趨勢，並分析不同拓樸網路之適用情境與可控制之輸入阻抗，以提升系統錯位容忍度。
最後，實驗結果本文所提出之PPSC在傳輸距離D = 40 mm時傳能效率為49%，而在水平錯位線圈面積一半Dx = 35 mm的情境下，衰減率僅有20%；PBSC在同樣的情境D = 40 mm以更小的線圈面積達到更高的傳能效率73%，而水平錯位線圈面積一半Dx = 25 mm時，衰減率更只有7%，經由FoM所算為5.22，在多數文獻比較中其性能指標皆大幅領先他者。本篇論文不僅止於設計線圈，更實驗對小型生醫植入式線圈傳能效率、錯位容忍度至整體系統效率隨錯位衰減程度，驗證本文提出之傳能系統具有極高的空間自由度與系統穩定性。

In this thesis, two novel serpentine (meander) structure coils are applied for wireless power transfer (WPT) system, which are proposed to improve the lateral misalignment tolerance for the potential applications of biomedical implants. Next, the dual-capacitance topologies are analyzed and derived to optimize the power transfer efficiency. Compared to the traditional WPT system that is combined with spiral coil and single capacitance for conjugate matching, the dual-capacitance topologies have more flexibility to adjust coil distance, source impedance and load impedance to operate at the optimal efficiency. In addition, the suitable topology can be selected for enhancing the robustness of system efficiency are also analyzed.
From experiment, the proposed planar parallel serpentine coil (PPSC) achieve 49% of efficiency at a transmission distance of 40 mm. The transfer power decay rate (TPDR) of PPSC is only 20% under laterally misaligned half of the coil area Dx = 35 mm. The decay rate of conventional spiral coil is 57% at the same situation. More than this, parallel butterfly-shape serpentine coil is proposed for power transfer efficiency enhancement and miniaturization but also inherited the advantage of misalignment tolerance characteristic by serpentine structure. The proposed PBSC achieve 73% of efficiency at a distance of 40 mm and only 7% of decay rate at laterally misaligned half of the coil area Dx = 25 mm. Therefore, it can validate that the proposed structures suffer better misalignment tolerance but also maintain high power transfer efficiency to achieve a more convenient wireless power transfer system.

[1] S. Singh, T. Hasarmani, and R. Holmukhe, "Wireless Transmission of Electrical Power Overview of Recent Research & Development," International Journal of Computer and Electrical Engineering, pp. 207-211, 01/01 2012.
[2] A. Kurs, A. Karalis, R. Moffatt, J. D. Joannopoulos, P. Fisher, and M. Soljačić, "Wireless Power Transfer via Strongly Coupled Magnetic Resonances," Science, vol. 317, p. 83, 2007.
[3] A. Karalis, J. D. Joannopoulos, and M. Soljačić, "Efficient wireless non-radiative mid-range energy transfer," Annals of Physics, vol. 323, pp. 34-48, 2008/01/01/ 2008.
[4] S. Yuan, Y. Huang, J. Zhou, Q. Xu, C. Song, and G. Yuan, "A High-Efficiency Helical Core for Magnetic Field Energy Harvesting," IEEE Transactions on Power Electronics, vol. 32, pp. 5365-5376, 2017.
[5] K. Agarwal, R. Jegadeesan, Y.-X. Guo, and N. v. Thakor, "Wireless Power Transfer Strategies for Implantable Bioelectronics: Methodological Review," IEEE Reviews in Biomedical Engineering, vol. PP, pp. 1-1, 03/16 2017.
[6] S. Ha, C. Kim, J. Park, S. Joshi, and G. Cauwenberghs, "Energy Recycling Telemetry IC With Simultaneous 11.5 mW Power and 6.78 Mb/s Backward Data Delivery Over a Single 13.56 MHz Inductive Link," IEEE Journal of Solid-State Circuits, vol. 51, pp. 2664-2678, 2016.
[7] J. C. Schuder and H. E. Stephenson, "Energy Transport to a Coil Which Circumscribes a Ferrite Core and Is Implanted Within the Body," IEEE Transactions on Biomedical Engineering, vol. BME-12, pp. 154-163, 1965.
[8] R. Zhang and C. K. Ho, "MIMO Broadcasting for Simultaneous Wireless Information and Power Transfer," IEEE Transactions on Wireless Communications, vol. 12, pp. 1989-2001, 2013.
[9] C. Yang, C. Chang, S. Lee, S. Chang, and L. Chiou, "Efficient Four-Coil Wireless Power Transfer for Deep Brain Stimulation," IEEE Transactions on Microwave Theory and Techniques, vol. 65, pp. 2496-2507, 2017.
[10] C. Chen, T. Chu, C. Lin, and Z. Jou, "A Study of Loosely Coupled Coils for Wireless Power Transfer," IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 57, pp. 536-540, 2010.
[11] K. Fotopoulou and B. W. Flynn, "Wireless Power Transfer in Loosely Coupled Links: Coil Misalignment Model," IEEE Transactions on Magnetics, vol. 47, pp. 416-430, 2011.
[12] Y. Zhang, Z. Zhao, and K. Chen, "Frequency-Splitting Analysis of Four-Coil Resonant Wireless Power Transfer," IEEE Transactions on Industry Applications, vol. 50, pp. 2436-2445, 2014.
[13] A. Qusba, A. K. RamRakhyani, J. So, G. J. Hayes, M. D. Dickey, and G. Lazzi, "On the Design of Microfluidic Implant Coil for Flexible Telemetry System," IEEE Sensors Journal, vol. 14, pp. 1074-1080, 2014.
[14] Y. Yao, Y. Wang, X. Liu, K. Lu, and D. Xu, "Analysis and Design of an S/SP Compensated IPT System to Minimize Output Voltage Fluctuation Versus Coupling Coefficient and Load Variation," IEEE Transactions on Vehicular Technology, vol. 67, pp. 9262-9272, 2018.
[15] S. Aldhaher, P. C. Luk, and J. F. Whidborne, "Electronic Tuning of Misaligned Coils in Wireless Power Transfer Systems," IEEE Transactions on Power Electronics, vol. 29, pp. 5975-5982, 2014.
[16] L. Shen, W. Tang, H. Xiang, and W. Zhuang, "Uniform magnetic field by changing the current distribution on the planar coil for displacement-insensitive wireless power transfer/near field communication," Microwave and Optical Technology Letters, vol. 57, pp. 424-427, 2015/02/01 2015.
[17] S. Wang, Z. Hu, C. Rong, C. Lu, J. Chen, and M. Liu, "Planar Multiple-Antiparallel Square Transmitter for Position-Insensitive Wireless Power Transfer," IEEE Antennas and Wireless Propagation Letters, vol. 17, pp. 188-192, 2018.
[18] U. Jow and M. Ghovanloo, "Geometrical Design of a Scalable Overlapping Planar Spiral Coil Array to Generate a Homogeneous Magnetic Field," IEEE Transactions on Magnetics, vol. 49, pp. 2933-2945, 2013.
[19] Y. Tanaka, T. Fujita, T. Kotoge, K. Yamaguchi, K. Sonoda, K. Kanda, et al., "Design Optimization of Electromagnetic MEMS Energy Harvester with Serpentine Coil," in 2013 IEEE International Conference on Green Computing and Communications and IEEE Internet of Things and IEEE Cyber, Physical and Social Computing, 2013, pp. 1656-1658.
[20] O. Oshiro, H. Tsujimoto, and K. Shirae, "High Frequency Characteristics of a Planar Inductor and a Magnetic Coupling Control Device," IEEE Translation Journal on Magnetics in Japan, vol. 6, pp. 436-442, 1991.
[21] S. M. Djurić, N. M. Djurić, and M. S. Damnjanović, "The optimal useful measurement range of an inductive displacement sensor," Electronic Components and Materials, vol. 45, pp. 132-141, 2015.
[22] R. Mendes Duarte and G. Klaric Felic, "Analysis of the Coupling Coefficient in Inductive Energy Transfer Systems," Active and Passive Electronic Components, vol. 2014, p. 6, 2014.
[23] M. S. Damnjanovic, L. D. Zivanov, L. F. Nagy, S. M. Djuric, and B. N. Biberdzic, "A Novel Approach to Extending the Linearity Range of Displacement Inductive Sensor," IEEE Transactions on Magnetics, vol. 44, pp. 4123-4126, 2008.
[24] M. Zargham and P. G. Gulak, "Maximum Achievable Efficiency in Near-Field Coupled Power-Transfer Systems," IEEE Transactions on Biomedical Circuits and Systems, vol. 6, pp. 228-245, 2012.
[25] R. Xue, K. Cheng, and M. Je, "High-Efficiency Wireless Power Transfer for Biomedical Implants by Optimal Resonant Load Transformation," IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 60, pp. 867-874, 2013.
[26] U. Jow and M. Ghovanloo, "Design and Optimization of Printed Spiral Coils for Efficient Transcutaneous Inductive Power Transmission," IEEE Transactions on Biomedical Circuits and Systems, vol. 1, pp. 193-202, 2007.
[27] S. Mehri, A. C. Ammari, J. B. H. Slama, and M. Sawan, "Design Optimization of Multiple-Layer PSCs With Minimal Losses for Efficient and Robust Inductive Wireless Power Transfer," IEEE Access, vol. 6, pp. 31924-31934, 2018.
[28] M. Fu, T. Zhang, C. Ma, and X. Zhu, "Efficiency and Optimal Loads Analysis for Multiple-Receiver Wireless Power Transfer Systems," IEEE Transactions on Microwave Theory and Techniques, vol. 63, pp. 801-812, 2015.
[29] Z. Miao, D. Liu, and C. Gong, "Efficiency Enhancement for an Inductive Wireless Power Transfer System by Optimizing the Impedance Matching Networks," IEEE Transactions on Biomedical Circuits and Systems, vol. 11, pp. 1160-1170, 2017.
[30] P. K. S. Jayathurathnage, A. Alphones, and D. M. Vilathgamuwa, "Optimization of a Wireless Power Transfer System With a Repeater Against Load Variations," IEEE Transactions on Industrial Electronics, vol. 64, pp. 7800-7809, 2017.
[31] J. Wang, M. Leach, E. G. Lim, Z. Wang, and Y. Huang, "Investigation of magnetic resonance coupling circuit topologies for wireless power transmission," Microwave and Optical Technology Letters, vol. 61, pp. 1755-1763, 2019/07/01 2019.
[32] D. Ahn and S. Hong, "A Study on Magnetic Field Repeater in Wireless Power Transfer," IEEE Transactions on Industrial Electronics, vol. 60, pp. 360-371, 2013.
[33] A. Barakat, K. Yoshitomi, and R. K. Pokharel, "Design Approach for Efficient Wireless Power Transfer Systems During Lateral Misalignment," IEEE Transactions on Microwave Theory and Techniques, vol. 66, pp. 4170-4177, 2018.
[34] L. L. Pon, S. K. A. rahim, C. Y. Leow, M. Himdi, and M. Khalily, "Displacement-Tolerant Printed Spiral Resonator With Capacitive Compensated-Plates for Non-Radiative Wireless Energy Transfer," IEEE Access, vol. 7, pp. 10037-10044, 2019.
[35] S. Hekal, A. B. Abdel-Rahman, H. Jia, A. Allam, A. Barakat, and R. K. Pokharel, "A Novel Technique for Compact Size Wireless Power Transfer Applications Using Defected Ground Structures," IEEE Transactions on Microwave Theory and Techniques, vol. 65, pp. 591-599, 2017.
[36] N. Ha-Van and C. Seo, "Butterfly-Shaped Transmitting Coil for Wireless Power Transfer System in Millimeter-Sized Biomedical Implants," in 2018 IEEE Wireless Power Transfer Conference (WPTC), 2018, pp. 1-4.
[37] S. A. Mirbozorgi, P. Yeon, and M. Ghovanloo, "Robust Wireless Power Transmission to mm-Sized Free-Floating Distributed Implants," IEEE Transactions on Biomedical Circuits and Systems, vol. 11, pp. 692-702, 2017.
[38] T. Yu, W. Huang, and C. Yang, "Design of Dual Frequency Mixed Coupling Coils of Wireless Power and Data Transfer to Enhance Lateral and Angular Misalignment Tolerance," IEEE Journal of Electromagnetics, RF and Microwaves in Medicine and Biology, vol. 3, pp. 216-223, 2019.
[39] L. L. Pon, C. Y. Leow, S. K. A. Rahim, A. A. Eteng, and M. R. Kamarudin, "Printed Spiral Resonator for Displacement-Tolerant Near-Field Wireless Energy Transfer," IEEE Access, vol. 7, pp. 172055-172064, 2019.
[40] Y. Li, J. Zhao, Q. Yang, L. Liu, J. Ma, and X. Zhang, "A Novel Coil With High Misalignment Tolerance for Wireless Power Transfer," IEEE Transactions on Magnetics, vol. 55, pp. 1-4, 2019.
[41] D. Liu, H. Hu, and S. V. Georgakopoulos, "Misalignment Sensitivity of Strongly Coupled Wireless Power Transfer Systems," IEEE Transactions on Power Electronics, vol. 32, pp. 5509-5519, 2017.
[42] Q. Zhu, Y. Guo, L. Wang, C. Liao, and F. Li, "Improving the Misalignment Tolerance of Wireless Charging System by Optimizing the Compensate Capacitor," IEEE Transactions on Industrial Electronics, vol. 62, pp. 4832-4836, 2015.
[43] Y. Lim, H. Tang, S. Lim, and J. Park, "An Adaptive Impedance-Matching Network Based on a Novel Capacitor Matrix for Wireless Power Transfer," IEEE Transactions on Power Electronics, vol. 29, pp. 4403-4413, 2014.
[44] M. Fu, H. Yin, X. Zhu, and C. Ma, "Analysis and Tracking of Optimal Load in Wireless Power Transfer Systems," IEEE Transactions on Power Electronics, vol. 30, pp. 3952-3963, 2015.