WIRELESS POWER TRANSFER – PRINCIPLES AND ENGINEERING EXPLORATIONS Edited by Ki Young Kim Wireless Power Transfer – Principles and Engineering Explorations Edited by Ki Young Kim Published by InTech Janeza Trdine 9, 51000 Rijeka, Croatia Copyright © 2011 InTech All chapters are Open Access distributed under the Creative Commons Attribution 3.0 license, which allows users to download, copy and build upon published articles even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications After this work has been published by InTech, authors have the right to republish it, in whole or part, in any publication of which they are the author, and to make other personal use of the work Any republication, referencing or personal use of the work must explicitly identify the original source As for readers, this license allows users to download, copy and build upon published chapters even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications Notice Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher No responsibility is accepted for the accuracy of information contained in the published chapters The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book Publishing Process Manager Jelena Marusic Technical Editor Teodora Smiljanic Cover Designer InTech Design Team First published January, 2012 Printed in Croatia A free online edition of this book is available at www.intechopen.com Additional hard copies can be obtained from orders@intechweb.org Wireless Power Transfer – Principles and Engineering Explorations, Edited by Ki Young Kim p cm ISBN 978-953-307-874-8 free online editions of InTech Books and Journals can be found at www.intechopen.com Contents Preface IX Chapter The Phenomenon of Wireless Energy Transfer: Experiments and Philosophy Héctor Vázquez-Leal, Agustín Gallardo-Del-Angel, Roberto Casteda-Sheissa and Francisco Javier González-Martínez Chapter Analysis of Wireless Power Transfer by Coupled Mode Theory (CMT) and Practical Considerations to Increase Power Transfer Efficiency 19 Alexey Bodrov and Seung-Ki Sul Chapter Magnetically Coupled Resonance Wireless Power Transfer (MR-WPT) with Multiple Self-Resonators Youngjin Park, Jinwook Kim and Kwan-Ho Kim 51 Chapter Network Methods for Analysis and Design of Resonant Wireless Power Transfer Systems 65 Marco Dionigi, Alessandra Costanzo and Mauro Mongiardo Chapter Performance Analysis of Magnetic Resonant System Based on Electrical Circuit Theory 95 Hisayoshi Sugiyama Chapter Equivalent Circuit and Calculation of Its Parameters of Magnetic-Coupled-Resonant Wireless Power Transfer 117 Hiroshi Hirayama Chapter Compact and Tunable Transmitter and Receiver for Magnetic Resonance Power Transmission to Mobile Objects 133 Takashi Komaru, Masayoshi Koizumi, Kimiya Komurasaki, Takayuki Shibata and Kazuhiko Kano Chapter Realizing Efficient Wireless Power Transfer in the Near-Field Region Using Electrically Small Antennas 151 Ick-Jae Yoon and Hao Ling VI Contents Chapter A Fully Analytic Treatment of Resonant Inductive Coupling in the Far Field 173 Raymond J Sedwick Chapter 10 Enhanced Coupling Structures for Wireless Power Transfer Using the Circuit Approach and the Effective Medium Constants (Metamaterials) 191 Sungtek Kahng Chapter 11 Maximizing Efficiency of Electromagnetic Resonance Wireless Power Transmission Systems with Adaptive Circuits 207 Huy Hoang and Franklin Bien Chapter 12 AC Processing Controllers for IPT Systems 227 Hunter Hanzhuo Wu, Grant Anthony Covic and John Talbot Boys Chapter 13 A High Frequency AC-AC Converter for Inductive Power Transfer (IPT) Applications Hao Leo Li, Patrick Aiguo Hu and Grant Covic 253 Preface Research and development in wireless power transfer technologies have witnessed fast-growing advancements in various fundamental and application fields due to the availability of highly developed analytical methods, measurement techniques, advanced numerical simulation tools, and an increase in practical business demands The recent advancements have also been accompanied by the appearance of various interdisciplinary topics This book puts state-of-the-art research and development in wireless power transfer technologies together It consists of 13 chapters that focus on interesting topics of wireless power links (first 10 chapters), and several system technology issues (last chapters), in which analytical methodologies, computational simulation techniques, measurement techniques and methods, and applicable examples are investigated This book concerns itself with recent and advanced research results and brief reviews on wireless power transfer technologies covering the aforementioned topics The advanced techniques and research described here may also be applicable to other contemporary research areas in wireless power transfer technologies Thus, I hope the readers will be inspired to start or further their own research and technologies and expand potential applications Although the book is a collected edition of specific technological issues, I strongly believe that the readers can obtain ideas and knowledge of the state-of-the-art technologies in wireless power transfer I would like to express my sincere gratitude to all the authors for their outstanding contributions to this book Ki Young Kim 258 Wireless Power Transfer – Principles and Engineering Explorations Fig Converter operation when input voltage VAC>0 free oscillation circuit enabling the energy to circulate between the capacitor C and inductor L However, if the peak current is larger than the reference -Iref at t3, the converter operates in Mode IV at the next half cycle of t4 If the negative peak current is still smaller than the reference -Iref after a positive energy injection (for example, peak current is still very small at t6 even after the injection at t5, and more energy is still needed in the next positive half cycles of t7.), then, the converter will operate at Mode I at t7, and continue to repeat the operation between Mode I and Mode III in the following half cycles until its peak magnitude larger than the predefined reference value The operation of the converter is similar to the situation when the input voltage VAC0 VAC 0 ˆ iL