Wireless power transfer via magnetic resonance coupling from. We present a quantitative model describing the power transfer, which matches the experimental results to within 5%. Design of wireless power transfer system via magnetic. Figure 1 shows a wireless power transfer system with two magneticallycoupled coils. Both of them use magnetic eld to transfer power and magnetic coil to feedpickup power. Wireless energy transfer using magnetic resonance ieee. Loose coupling or tight coupling between the tx and rx coils. Resonant inductive coupling is also being used in wireless power systems for portable computers, phones, and vehicles. Wireless power transfer wpt using strongly coupled magnetic. Wireless power transmission using magnetic resonance mandip jung sibakoti and joey hambleton cornell college phy312, december 2011, professor derin sherman 1.
Design of wireless electric power transfer technology. Hence, by operating the coils at a resonant frequency, hightransmission efficiency can be achieved. Quantum computing explained with a deck of cards dario gil, ibm research duration. Two resonant objects of the same resonant frequency tend to exchange energy efficiently, while interacting weakly with extraneous offresonant objects. Wireless power transmission using magnetic resonance by. Previous methods for wireless transmission include attempt by the late scientist nikola tesla and the microwave power transmission. Oneton wireless power transmission system based on. Transfer efficiency optimal control of magnetic resonance. This achieves better power transfer efficiency and everybody knows this. The final edited and typeset version of record will appear in the future. The team was able to wirelessly power a 60watt light bulb using a pair of 20in. In 1899, nikola tesla, who had devised a type of resonant transformer called the tesla coil, achieved a major breakthrough in his work by transmitting 100 million volts of electric power wirelessly over a distance of 26 miles to light up a bank of 200 light bulbs and run one electric. Wireless power supplies using magnetic resonance may 2010, by john messina magnetic induction is the concept used in wireless power supplies.
Using copper coils, power can be transmitted several feet in all directions efficiently. Reconfigurable magnetic resonancecoupled wireless power. Inductive charging pad for lg smartphone, using the qi system, an example of nearfield wireless transfer. Nuclear magnetic resonance by miles mathis first published september 24, 20 i was asked to look at this problem by a physicist who works in the field of nuclear magnetic resonance, using the big machines on a daily basis. Wireless power transfer via strongly coupled magnetic resonances. A magnetic resonance wireless power transfer wpt system achieves maximum power transfer efficiency pte at the position where critical coupling occurs, but the pte degrades significantly off this position. When the system is properly designed, electromagnetic energy is inductively coupled from a driver loop to the transmitter resonant coils that. Click on the title to browse this list of accepted articles.
Mathematical expressions of optimal coupling coefficients were examined with the coupling model. Wireless energy transfer through nonresonant magnetic coupling. Wireless power transfer via magnetic resonance coupling has generated considerable attention because such transfers have high efficiency and produce a large air gap1. We have been doing this in the medical device industry for at least the last two decades. Wireless power transfer via magnetic resonant coupling is widely researched for various applications especially for charging electric vehicles. The aim is to transfer energy wirelessly from transmitter coil. Induction technique inductive coupling any contactless transfer energy method based on electromagnetic field, follows the laws of maxwell, although in case of near field methods the most important is the varia. Resonance energy transfer the resonance transfer of energy between molecules, or between sites within a large molecule, plays a central role in many areas of modern chemistry and physics. Wireless power transmission using magnetic resonance. This dream is starting to become a reality thanks to magnetic resonance, magnetic induction and. It provides flexibility in case of relative orientation between the power source and device during the operation. May, 2010 until now domestic manufacturers and research institutions have only been focused on the concept that magnetic resonance could be used for wireless power supplies. Wireless power transmission technology using magnetic resonance coupling, offering wireless midrange power transmission, was originally proposed by a research group led by marin soljacic from mit in 2007. Wireless power transfer via magnetic resonance coupling.
Optimization of wireless power transfer via magnetic. The key point of the magnetic coupled resonant wpt is using capacitance to occur resonance. Wireless power transfer lane is constructed by embedding the coils beneath the road to provide charging coverage to certain distance. Drawing power from an electrical outlet, the source coil created a magnetic field. Studies show that the resonant frequencies of the two antennas change according to the air gap in between the antennas. Rf harvesting before he died, nikola tesla promised a world built on wireless charging technology. If a proper resonant waveguide is brought near the transmitter, the. Magnetic coupling is an old and well understood method in the field of wireless power transfer. Analysis of resonant coupling coil configurations of ev wireless. Introduction our project was based upon a mit published paper in the year 2007 titled wireless power transfer via strongly coupled magnetic resonances 1. Multiband wireless power transfer via resonance magnetic.
These are the accepted, unedited articles published online and citable. Architects of wireless power transfer systems face a couple of choices in the configurations of coils and the magnetic transfer technique. Resonance coupling technique for wireless energy transfer. This article traces some early work of tesla and other researchers related to the use of magnetic resonance. Sony develops highly efficient wireless power transfer system. Wireless energy transfer by resonant inductive coupling master of science thesis rikard vinge. The resonant frequency changes from two to one depending on the critical condition. Wireless energy transfer using magnetic resonance abstract.
Wireless energy transfer technology using electromagnetic. First, we analytically derive the optimal geometric parameters for transmission of power in the air. Using this system, up to 60 watts of electrical energy can be transferred over a distance of 50cm at an efficiency of approximately 80%, approximately 60% including rectifier. Magnetic resonance an overview sciencedirect topics. The project was researched by former cornell students lucas jorgensen and adam culberson in the year 2008 2. Pdf dynamic wireless power transfer, which is not a new concept, was developed several years ago. The frequency expression of maximum efficiency and the resonant frequency splitting phenomenon condition of a contactless power transmission system were derived. It should be noted that the potential for tissue heating caused by induced currents in passive or active medical implants are. Novel numerical and experimental approaches which provide a scienti.
Two resonant objects tend to exchange energy efficiently. In my opinion, for the last thirty years, nearly all magnetic induction energy transfer systems place a capacitor to put the secondary coil in resonance. In the transmitter coil, the electric energy is converted to magnetic energy which is picked up in the receiver coil where it is converted back to electrical energy. The power transferred to a receiver load at resonance is derived and explained. Wireless power transfer algorithms, technologies and applications.
Energy is provided by a dedicated source, in this case an electric motor, and transferred trough the magnetic coupling onto the rotor inside the harvester. Comparing to other conventional contactless energy transfer mechanisms, midrange wireless electricity transmission using magnetic resonant coupling provides some functional benefits. This system transfers 45w power wirelessly via magnetic resonance. This chapter provides a general overview of magnetic resonant wireless power transfer systems based on network models. Although the magnetic coupled resonant wpt technology is the epochmaking technology, this technology seems similar technology to magnetic induction. The focus is to get high efficiency of more than 60% between 10 to 20 cm.
Smfir is a basic technology that can be used in many applications where electric power has to be supplied remotely without using conductive wires. But as the magnetic field decay very quickly, magnetic field is effective only at a very short distance. Wireless power transmission by magnetic resonance circuits. This specifically leads to the identification of the local and global optimization. Wireless power transmission using magnetic resonance ijert.
Magnetic resonant coupling based wireless power transfer. Magnetic resonance has been a cornerstone of nonradiative wireless power transfer wpt since the late 19th century. Basic principles of magnetic resonance i historical background. A magnetic resonance wireless power transfer system robust. Bulk water molecules have many mechanical degrees of freedom, and motion of such molecules thus exhibits statistically averaged behavior. Transfer via magnetic resonance coupling impedance matching and power division utilizing impedance inverter k. Analysis and optimization of magnetic resonant wireless power transfer system figure 2. A wireless magnetic resonance energy transfer system for. In this paper, a higheciency wireless energy transmission via magnetic resonance is implemented by using the negative permeability metamaterial structures as the magnetic ux guide. When the phone is set on the pad, a coil in the pad creates a magnetic field which induces a current in another coil, in the phone, charging its battery. However, the magnetic resonant coupling and inductive coupling methods are. Pdf wireless power transfer via magnetic resonance coupling. Energy transfer systems mostly use antennas operating in their near field regions. The project was done at nextfloor oy, a company based in helsinki, finland.
The same device can thus powermems 2014 iop publishing. Magnetic resonance for wireless power transfer a look back. Currently i am working on wireless power transfer using magnetic resonance coupling mrc, inductive and acoustic methods. Wireless energy transfer through nonresonant magnetic. In this paper, we propose a new design technique that can achieve high pte over a wide range by generating critical coupling at two other positions by using a switchless passive dual. This means that there is a wireless energy transfer between the source and the receiver the harvester.
These coils can be used to provide energy for wireless sensors and batteryoperated devices. Wireless energy transfer using resonant magnetic induction. Lucas jorgensen and adam culberson in conjunction with professor derin sherman introduction we experimented with wireless power transmission. The scmr method has achieved 40% wireless power transfer efficiency in the air for a distance of 2 m for a single receiver 6, and the scmr. Magnetic resonance wireless power transfer for laptop. Equivalent circuit parameters were calculated with maxwell 3d software, and then, the equivalent circuit was solved using matlab technical computing software.
Wireless power transfer via strongly coupled magnetic resonances 1. In order to suppress the fast decrease of the transfer efficiency of magnetic resonance coupled wireless power transfer system mrcwpts with distance increase, this paper investigates the impact factors of the system transfer efficiency and is, then formulates a new efficiency optimal control method based on frequency control. Magnetic resonance is a very useful technique of solid state investigation. Efficiency, resonance frequency, wireless power transfer. In some instances, this technology is also referred to as magnetic resonance, and it is often contrasted to induction for its ability to efficiently transfer. Wireless power transfer wpt, wireless power transmission, wireless energy. In 1899, nikola tesla, who had devised a type of resonant transformer called the tesla coil, achieved a major breakthrough in his work by transmitting 100 million volts of electric power wirelessly over a distance of 26 miles to light up a bank of 200 light bulbs and run one electric motor. Design principles one of the most promising applications of the lefthanded metamaterials lhms is the veselagopendry lens made of a single slab of a. In, tesla achieved a great progress by designing a resonance.
Using selfresonant coils in a strongly coupled regime, we experimentally demonstrated efficient nonradiative power transfer over distances up to 8 times the radius of the coils. One of the wpt enabling technologies is the magnetic resonance coupling. Pdf dynamic wireless power transfer system using coupled. In magnetic resonance imaging or nmr of macromolecular samples, such as protein solutions, at least two types of water molecules, free bulk and bound hydration, are present. Mediumrange implies that the transfer distance is up to a few times larger than the device dimension. Experiments and philosophy 3 strong electromagnetic resonance. Magnetic resonant coupling based wireless power transfer system with inband power transmitting system. Inductive coupling provides optimum power delivery to a receiver load if both the emitter and the receiver achieve magnetic resonance concurrently. Tentzeris the school of electrical and computer engineering, georgia institute of technology, atlanta, ga, 30332, usa. Magnetic resonance and magnetic induction what is the best choice for my application. In order to reduce the dependency on battery capacity, charging while the vehicle is moving may be a solution. Is there any difference between induction and resonant. Hori department of electrical engineering, the university of tokyo, japan department of advance energy, the university of tokyo, japan abstractfuture applications of wireless power.
Wireless power transfer by using magnetically coupled. Witricity type magnetic resonance coupling systems add another set of resonant coils on the primary power source side which pair with the coils on the secondary load bearing side. Recently, a highly efficient midrange wireless power transfer technology using electromagnetic resonance coupling, witricity, was proposed. Wireless power transfer is a novel technology and the theory is based on magnetic resonant circuit. Multiband wireless power transfer via resonance magnetic olutola jonah and stavros v. Abu qahouq, journalieee transactions on power electronics, year2015, volume30. They used a selfmade wireless power device to power a 60watt bulb from a distance of 2 m, with an efficiency of 4050%.
Design of wireless power transfer system via magnetic resonant coupling at. Wireless power transfer via strongly coupled magnetic. In a weak coupling at resonance, magnetic resonant coupling can transfer energy with high efficiency. Magnetic resonance, absorption or emission of electromagnetic radiation by electrons or atomic nuclei in response to the application of certain magnetic fields. Parameters optimization for magnetic resonance coupling. Wireless power transmission via magnetic resonant coupling. The entire system is composed of the in vitro part, including the. Wireless energy transfer by resonant inductive coupling. Analysis of dead zone in wireless power transfer via magnetic.
Since the pioneering experiments on ret by cario and franck in 1922, the theoretical understanding of the process has been continually refined. Keywordswireless power transmission, magnetic resonance, evanescentwave coupling, relaxation oscillator. Tesla claimed to have achieved 95% efficiency, but the technology had to be shelved because the effects. Equivalent circuit and calculation of its parameters of. The transfer is made through inductive coupling and electromagnetic radiation. In this paper, we use coupled inductance model in circuit theory to analyze the power transfer efficiency of this technology, instead of using coupled mode theory cmt. Analysis of wireless energy transfer system using magnetic. However, some researchers have the misconception that magnetic resonance for.
Setjoadi, a sharpe, n, wireless power transfer using weakly coupled. Studies show that the resonant frequencies of the two antennas change according to. Pdf modelling and efficiencyanalysis of wireless power. Yet, there has been a misconception among some researchers who think magnetic resonance for wpt was developed recently. In this chapter, a wireless power transmission system based on magnetic resonance coupling circuit was carried out. Opportunities and challenges for nearfield wireless power transfer. Georgakopoulos department of electrical engineering, florida international university, miami, fl 33174, usa manos m. Besides magnetic resonance, wireless power supplies can also be designed using microwaves. Modelling and efficiencyanalysis of wireless power transfer using magnetic resonance coupling. Based on the magnetic resonance coupling principle, in this paper a wireless energy transfer system is designed and implemented for the power supply of microimplantable medical sensors.
Sony corporation today announced the development of a highly efficient wireless power transfer system that eliminates the use of power cables from electronic products such as television sets. The probability density functions pdf of the noise and ms with normal. Analysis and optimization of magnetic resonant wireless. Electromagnetic field as the wireless transporter of energy 173 2. Nuclear magnetic resonance was discovered decades ago and is now used in many fields, including medicine. Wireless power transfer via strongly coupled magnetic resonances andre kurs, 1 aristeidis karalis,2 robert moffatt, j. Wireless power transfer via strongly coupled magnetic resonances andre kurs,1 aristeidis karalis,2 robert moffatt,1 j. Research institute, korea electric power corporation kepco, 105 munji. Conclusion wireless energy transfer is completely has potential to be improved and magnetic resonance coupling is most feasible method in wireless energy transfer.
The optimization of wireless power transfer via strongly coupled magnetic resonance scmr to sensors embedded in concrete is studied here. The scmr method is a novel nonradiative wireless midrange power transfer method 10 300 cm that has been recently developed 69. It is shown that for every system, a resonance frequency can be identified where. Automated impedance matching system for robust wireless power.
The boxes indicate lower ground and excited electronic states here, designated as singlet. During the course of this research, we investigated the need and usefulness of wireless power transmission and the feasibility of using magnetic inductive. Resonant wireless power transfer infineon technologies. The energy can be transferred via magnetic resonant circuit using nonradiative near field.
The goal of the project was to develop a wireless power transfer wpt system and implement it in innovative flooring. Magnetic resonance wireless power transfer for laptop computer with a ground plane. Both tesla design and later microwave power were forms of radiative power transfer. By applying resonance with in magnetic coupling, the power transfer at. It proposed energy transmission in free space using electromagnetic waves.
Witricity corporation provides technology to enable wireless power transfer over distance using magnetic resonance. Circuit analysis of wireless power transfer by coupled. This phenomenon can be explained using the coupledmode theory. Resonance energy transfer ret, the transport of electronic energy from one atom or molecule to another, has significant importance to a number of diverse areas of science. The use of this technique to wirelessly transfer energy across a short distance is, however, expected to see an explosive growth over the next decade in a much broader range of applications from advanced implantable microelectronic devices imd, such as retinal implants and braincomputer interfaces bci to cut the power cord in charging.
Theoretical foundations and developing applications 465 figure 14. Shinohara, n wireless power transfer via radiowaves. The mit team demonstrated the highly resonant technique using a magnetic field to transfer energy over a midrange distance of 2 meters, and an industry was born. Joannopoulos,1 peter fisher,3 marin soljacic1 1departm ent of physics, massachusetts institute of techn ol gy, cambrid e, ma 029, usa. The principles of magnetic resonance are applied in the laboratory to analyze the atomic and nuclear properties of matter electronspin resonance esr was first observed in 1944 by a soviet physicist, y. Multireceiver and repeater wireless power transfer via. Wireless energy transfer by coupled magnetic resonances is a popular technology in which energy can be transferred via coupled magnetic resonances in the nonradiative nearfield. Wireless energy transfer through magnetic reluctance coupling. Figure 1 a resonant wireless power transfer system consists of a driven lcresonator on the. Magnetic resonance coupling with centimeterscale size of coils has been designed in order to promote the application of magnetic resonance energy coupling in imds. In contrast, witricity is based on using coupled resonant objects. It provides flexibility in case of relative orientation between. In biophysics, for example, this process defines the migration of excitation energy within photosynthetic systems commonly the frster mechanism. Wireless power transfer wpt system based on magnetic resonance is presented here.
The circuit theory behind coupledmode magnetic resonance. Midrange wireless energy transfer using inductive resonance. Today, shortdistance wireless energy transfer is either based on capacitive or in. Kurs 2007 was introduced the method of wireless energy transfer, which use the strong electromagnetic resonance phenomenon, achieving energy transfer ef. Review of wireless power transfer via strongly coupled. Another important area is in crystals, laser and other laser.