Efficient wireless electric power transmission using magnetic resonance coupling. This chapter provides a general overview of magnetic resonant wireless power transfer systems based on network models. Multireceiver and repeater wireless power transfer via magnetic resonance coupling impedance matching and power division utilizing impedance inverter k. However, existing solutions are limited to near contact distances and do not provide the geometric freedom to enable automatic and unaided charging. Nearfield wpt refers to the distance of transfer energy within the wavelength. Basic study of improving efficiency of wireless power transfer via magnetic resonance coupling based on impedance matching teck chuan beh, takehiro imura, masaki kato yoichi hori. Introduction wireless charging 1, 2, also known as wireless power transfer, is the technology that enables a power source to transmit electromagnetic energy to an electrical load across.
It is easy to show that the keyto efficient energy transfer is to have. Wireless power transmission using magnetic resonance mandip jung sibakoti and joey hambleton cornell college phy312, december 2011, professor derin sherman 1. It provides flexibility in case of relative orientation between. Wireless energy transfer by resonant inductive coupling master of science thesis rikard vinge. Highefficiency wireless energy transmission using magnetic. Currently i am working on wireless power transfer using magnetic resonance coupling mrc, inductive and acoustic methods. The system may further include a coil formed around the array and electromagnetically coupled to the oscillators to produce. Wireless power transfer wpt using strongly coupled. These coils can be used to provide energy for wireless sensors and batteryoperated devices. Physics of highly resonant wireless power transfer resonance resonance is a phenomenon that occurs in nature in many different forms. Wireless power transfer has a long history, starting from the early 20th century with attempts by nikola tesla to implement large scale wireless power distribution using the earths ionosphere. Inductive coupling provides optimum power delivery to a receiver load if both the emitter and the receiver achieve magnetic resonance concurrently.
A wearable textile antenna for wireless power transfer by. However, the magnetic resonant coupling and inductive coupling methods are suitable for. The only technology that meets automaker requirements for wireless charging. 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.
Hori department of electrical engineering, the university of tokyo, japan department of advance energy, the university of tokyo, japan. The transfer is made through inductive coupling and electromagnetic radiation. Wireless power transfer via magnetic resonant coupling is experimentally demonstrated in a system with a large source coil and either one or two small receivers. Wireless power transmission via magnetic resonant coupling. The coils can be loosely coupled but demand a high q factor if energy transfer is to be maintained over several centimeters. It is shown that for every system, a resonance frequency can be identified where. Wireless energy transfer by resonant inductive coupling. Pdf wireless power transfer using coupled magnetic resonance. Can also be used for rotating parts such as a robot arm. The technologies, listed in the table below, differ in the distance over which they can transfer power efficiently, whether the transmitter must be aimed directed at the receiver, and in the type of electromagnetic energy they use.
Multiband wireless power transfer via resonance magnetic. Wireless power transfer using inductive coupling to transfer energy from a. Disclosed is an apparatus for use in wireless energy transfer, which includes a first resonator structure configured to transfer energy nonradiatively with a second resonator structure over a distance greater than a characteristic size of the second resonator structure. Wireless power transmission using magnetic resonance.
Comparing to other conventional contactless energy transfer mechanisms, midrange wireless electricity transmission using magnetic resonant coupling provides some functional benefits. Introduction our project was based upon a mit published paper in the year 2007 titled wireless power transfer via strongly coupled magnetic resonances 1. The paper presents a wearable textile antenna embroidered on a fabric for wireless power transfer systems. Quasistatic cavity resonance for ubiquitous wireless power.
Wireless power transmission by magnetic resonance circuits. Magnetic resonant coupling as a potential means for. Resonance between source and load coils is achieved with. If a proper resonant waveguide is brought near the transmitter, the. Design principles one of the most promising applications of the lefthanded metamate. The proposed mcrwpt system using magnetic resonance coupling. Em radiation using propagating waves, inductive coupling, and magnetic resonance coupling 1. Wireless energy transfer or wireless power is the transmission of electrical energy from a power source to an electric load without interconnecting man made conductors. A wireless magnetic resonance energy transfer system for. Kaminska, midrange wireless energy transfer using inductive resonance for wireless sensors, proceedings of the ieee international conference on computer design.
Resonant inductive coupling is also being used in wireless power systems for portable computers, phones, and vehicles. In contrast, witricity is based on using coupled resonant objects. Pdf efficient wireless electric power transmission using. Equivalent circuit and calculation of its parameters of magnetic coupledresonant wireless power transfer 3 ds d dd hs hd ra rb rs rd x y z port1 port2 fig. The energy can be transferred via magnetic resonant circuit using nonradiative near field. When the system is properly designed, electromagnetic energy is inductively coupled from a driver loop to the transmitter resonant coils that creates a magnetic. 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. The focus is to get high efficiency of more than 60% between 10 to 20 cm. The efficiency of the wireless transfer itself is hard to estimate in this way. Review of wireless power transfer via strongly coupled. Equivalent circuit and calculation of its parameters of. In addition, the use of batteries as a substitute for power cords is not an. A magneto mechanical system may include an array of magnetomechanical oscillators, wherein each oscillator may comprise a magnetic symmetrical part and a suspension engaged to the magnetic part.
Both the electromagnetic induction method and the magnetic resonance method are wireless power transfer systems which use magnetic coupling, and transfer power by using a high frequency power supply to pass the change in the high frequency magnetic field from the power transmission coil to the power reception coil. The magnetic resonance between two induction coils can be used to power a remote device through space over a distance of 2 meters. Wireless energy transfer using magnetic resonance abstract. In order to research the relationship between coupling distance and transmission efficiency, study on the transmission characteristics of magnetic resonant coupling for wireless power transmission system, simulation model of wireless power transmission system via magnetic resonance coupling were established based on the theory of two ports network analysis method.
Wireless power transfer via strongly coupled magnetic. In general, resonance involves energy oscillating between two modes, a familiar example being a mechanical pendulum in which energy oscillates between potential and kinetic forms. Witricity corporation provides technology to enable wireless power transfer over distance using magnetic resonance. Using copper coils, power can be transmitted several feet in all directions efficiently. An rfgated wireless power transfer system for wireless. A planar spiral coil was generated with the conductive thread on a cotton substrate, and was connected to a rectifier circuit fabricated on flexible polyethylene terephthalate film to constitute a bendable receiver by the magnetic resonance. This is achieved withoutexceedingtheexposurelimitofmagnetic. Efficient wireless nonradiative midrange energy transfer aristeidis karalis, j. The basic working principle of wireless power transfer is, two objects having similar resonant frequency and in magnetic resonance at powerfully coupled rule tends to exchange the energy, while dissipating relatively little energy to the extraneous offresonant objects. The wire has inductance l, the plates have capacitance c and then the system has a resonant mode, where the nature of the resonance lies in the periodic exchange of energy from the electric. In general, resonance denotes the oscillation of energy between.
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. Figure 1 a resonant wireless power transfer system consists of a driven lcresonator on the. Wireless power transfer using coupled magnetic resonance in the non radiative near field. Opportunities and challenges for nearfield wireless power transfer. Proposed positionfree mcrwpt array system with an array of 2. Wireless power transfer is a generic term for a number of different technologies for transmitting energy by means of electromagnetic fields. The first section of the document will explicitly illustrate the goals. Wireless electromagnetic energy tran sfer used for low power battery charging. In the em radiation technique, a highly directional antenna is used to transmit and receive microwave energy from point. Further, we design wireless energy transfer systems capableof a peakvaluepower transfer of 1. Multireceiver and repeater wireless power transfer via. Wireless power transmission using magnetic resonance by. Wireless power transfer by using magnetically coupled. Higher levels of transferred power is possible if larger magnetic.
Analysis of wireless energy transfer system using magnetic. We introduce quasistatic cavity resonance qscr, which can enable purposebuilt structures, such as cabinets. Wireless power transfer is a novel technology and the theory is based on magnetic resonant circuit. Two resonant objects of the same resonant frequency tend to exchange energy efficiently, while interacting weakly with extraneous offresonant objects. Lucas jorgensen and adam culberson in conjunction with professor derin sherman introduction we experimented with wireless power transmission. In this paper, a higheciency wireless energy transmission via magnetic resonance is implemented by using.
Magnetic resonance and magnetic induction what is the best choice for my application. Yet, there has been a misconception among some researchers who think magnetic resonance for wpt was developed recently. Magnetic resonance method of wireless power transfer technology for industrial equipment achieves wireless power transfer to mobile objects with high efficiency. Pdf this chapter provides a general overview of magnetic resonant wireless power transfer systems based on network models. Design and simulation of wireless power transfer systems mihai iordache, george andronescu, victor bucata, marialavinia iordache bobaru. Magnetic resonance coupling with centimeterscale size of coils has been designed in order to promote the application of magnetic resonance energy coupling in imds. Optimization of wireless power transfer via magnetic. The initial idea of wireless power transmission by magnetic resonance method was introduced by. Near field wpt refers to the distance of transfer energy within the wavelength. Pdf wireless power transfer via magnetic resonance coupling. Magnetic resonant coupling as a potential means for wireless power transfer to multiple small receivers.
In, tesla achieved a great progress by designing a resonance. Wireless power transfer is received using a magneto mechanical system. Building a wireless energy transfer circuit stepbystep. Resonant wireless power transfer infineon technologies. Wireless power transfer circuit working, advantages and. 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. Wireless power transfer via strongly coupled magnetic resonances andre kurs, 1 aristeidis karalis,2 robert moffatt, j. Wireless power delivery has the potential to seamlessly power our electrical devices as easily as data is transmitted through the air. In particular, energy transfer is often realized by using electromagnetic power, which can either. Wireless energy transfer using magnetic resonance ieee. The power transferred to a receiver load at resonance is derived and explained. Architects of wireless power transfer systems face a couple of choices in the configurations of coils and the magnetic transfer technique.
Wireless power transfer is an innovative approach using magnetic resonance coupling of air core transformers designed for todays growing plugin electric vehicle market. Effective alternative to squid superconducting quantum interference device. Inductive versus resonant wireless charging digikey. This dissertation, written by olutola jonah, and entitled optimization of wireless power transfer via magnetic resonance in different media, having been approved in respect to style and intellectual content, is referred to you for judgment. Wireless transmission is useful in cases where interconnecting wires are inconvenient, hazardous or impossible. Circuit analysis of wireless power transfer by coupled. Pdf the goal of the project was to develop a wireless power transfer wpt system and implement it in innovative flooring. Achieves wireless power transfer to mobile objects with.
Today, wireless powering is still accomplished by electromagnetic fields and can be categorized based on three frequency ranges used. The paper will outline our design process and the logical steps we took in the experimentation and design of our circuits. Sony develops highly efficient wireless power transfer. Design and simulation of wireless power transfer systems. 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. Figure 1 shows a wireless power transfer system with two magneticallycoupled coils. 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. The nonradiative energy transfer is mediated by a coupling of a resonant field evanescent tail of the first resonator. Magnetic resonance has been a cornerstone of nonradiative wireless power transfer wpt since the late 19th century. Wireless power transfer using coupled magnetic resonance in the nonradiative near field. Resonant wireless charging relies on a highfrequency oscillating magnetic field transferring energy between two coils operating at the same resonant frequency. We have read this dissertation and recommend that it be approved. Energy transfer systems mostly use antennas operating in. This article traces some early work of tesla and other researchers related to the use of magnetic resonance.