The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Impedance matching techniques were previously investigated for maximum power transfer efficiency in wireless power transfer system (WPT). In this paper, similar discipline is investigated and analyzed for reducing magnetic EMC in wireless power transfer system. Basic theory is reviewed, leading to appropriate application in the WPT system while investigating and analyzing the EMC reduction effect.
In this paper, the electromagnetic compatibility issues of wireless powered electric vehicle are discussed in the view of electromagnetic field and electromagnetic interference. The magnetic field reduction for human exposure for near field is investigated and the definition of electromagnetic interference measurement is discussed.
Retinal implants operating with inductive coils for wireless power and data transmission are being developed to help restore vision to the blind. In this work, we analyze temperature increase in the tissue surrounding a retinal implant due to resistive heating of the coils. Using principles of heat transfer and power dissipation data, we estimate temperature rise in the tissue. From our analysis,...
We present a medical resonance imaging (MRI) B1-field polarisation mapping system based on active electro-optical H-field probes. The active electro-optical field probes have a bandwidth ranging from 10 MHz to 6 GHz with a sensitivity of < −110dB(A/m)/√Hz at 128MHz. The miniature size of the probe elements (2×2 mm2) provides a high spatial resolution. The electrical isolation using fiber-optics...
We introduce a numerical assessment methodology to understand the EMI imposed by coupled-resonant type wireless power transfer systems on active implantable medical devices (implantable cardiac pacemaker / cardioverter defibrillator). A numerical estimation model that consists of resonant coils and a human torso phantom with a pacemaker model is constructed. Numerical simulation based on the finite...
This paper describes a measurement of microscopic radio frequency (RF) field distribution with a magnetic force microscope (MFM) tip exploring a beat signal from a coplanar waveguide (CPW). This CPW has a 5 μm wide signal line and a 50 μm wide ground line assuming a basic model of power/ground lines in radio frequency integrated circuit (RFIC) chips. To produce a beating field near the CPW, a signal...
An on chip active magnetic field probe has been developed for IC chip-level magnetic near field measurements. A low noise amplifier (LNA) and a loop coil were implemented in 0.18 μm Si-CMOS technology, and solder-bonded to PCB to complete the probe. Its gain is 13.3 dB at 2 GHz. The probe is applied for magnetic near field evaluation of a test element group (TEG) chip that emulates Long Term Evolution...
Compliance tests for railway signaling equipment are getting more important for manufacturing railway traction converters. The traction converters emit disturbance current interfering with track circuits and electromagnetic field interfering with magnetic loops, which are also called balises. The interference with balises is severe problem because the electromagnetic field has been unknown because...
The safety assessment of implant EM exposure is typically performed by numerically or experimentally evaluating field strengths in (frequently strongly simplified) phantoms or anatomical models. Determining quantities more closely related to the effect of concern can aid in detecting insufficient safety margins, reducing the necessity for overly conservative limits, and increasing the understanding...
Dosimetry for the two resonant modes of resonance-based wireless power transfer system is investigated and compared. We present the physical mechanism for the two resonant modes with the simulated results and the equivalent circuit models for the wireless power transfer system. The difference between the two resonant modes for the specific absorption rate induced in the head model is discussed by...
Wireless power transfer technologies have been extensively researched for several decades and successfully deployed on a commercial scale. As studies on wireless power transfer technologies have progressed and its feasibility has been tested, electromagnetic radiated emissions have become more important subject than before. In this paper, we report the measurement and analysis of the electromagnetic...
Until recently, the presence of an AIMD has been considered a contraindication to MRI because of the potential adverse effects of MRI on AIMDs. However, all of AIMD manufacturers have released “MR Conditional” devices recently. These devices have been demonstrated to pose no known hazards in a specified MRI environment with specified conditions of use. Therefore, it is quite important to understand...
This paper presents the research work focusing on charging the energy via the air to a small electric vehicle (EV). This work shows not only the possibility of wireless power charging, but also the electromagnetic compatibility (EM C) issue is taken into account. The charging system is described and set up using the resonance coupling effect and single-ended primary-inductor converter (SEPIC) for...
We examined the electromagnetic (EM) emissions of three commercially available systems that charge remote devices by use of inductive wireless power transfer (WPT) in the Low-Frequency (<300 KHz) range. All devices have passed applicable emissions regulations We measured the temporal and spectral characteristics of the char ging and information exchange between the charger and load. The basic WPT...
Recent advances in wireless power transmission have enabled various new applications, one of which is wireless charging of an electrical vehicle. In this application, electric power is wirelessly transmitted using strong electromagnetic fields from a coil located on the ground to another coil attached to the vehicle. In this study, we use computational modelling to investigate the human exposure to...
This paper deals with the magnetic shielding of the field generated by a wireless power transfer (WPT) system at the frequency of 20 kHz. Different shielding techniques are examined and discussed based on the use of conductive and magnetic material panels. The performances of the WPT system and the magnetic field shielding effectiveness (SE) in presence and in absence of shield panels are calculated...
The present study investigates the SAR (specific absorption rate) and the induced electric field in an anatomically based model for the magnetic field from a wireless power transfer system. The waiting and charging conditions are considered. The transfer frequency considered herein is from 100 kHz and 150 kHz where a magneto-quasi-static approximation is valid. A two-step quasi-static method comprised...
Magnetic resonant coupling between two coils allows effective wireless transfer of power over distances in the range of tens of centimetres to a few metres. The resonant magnetic field also extends to the surroundings of the power transfer system. When a person is exposed to this magnetic field, electric fields are induced in the body. It is necessary to evaluate whether these fields satisfy the human...
We developed wireless power transfer system using magnetic resonance, and measured the transmitting efficiency and the electromagnetic fields in the vicinity of system Then we made comparison between measured filed and the reference eve of the ICNIRP guideline As a results, the similar trend of transmitting efficiency was confirmed with previous studies, and we validated that not just magnetic field...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.