Magnetic Field Analysis of Wireless Power Transfer via Magnetic Resonant Coupling or Electric Vehicle

Now-a-days, wireless transfer of electric power has received much attention in the world arena. As a safe, reliable and convenient technology, Magnetic resonance coupling (MRC) based wireless power transfer (WPT) system shows a remarkable ability to power up in a wide range from mW to kW range. In this paper conventional magnetic field analysis with maximum power transfer theorem has been used to explain the frequency characteristics of the transferred load power. The intensity of magnetic field, induced receiver voltage, physical air gap of coils relating to the dimension of the coils has been examined. The experimental results are well agreed with the theoretical results. The acquired analysis depicts the optimal physical separation condition relating to the size of the charging coils of a WPT system

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Wireless power transfer (WPT) system for an electric vehicle (EV): how to shield the car from the magnetic field generated by two planar coils

Wireless Power Transfer ◽

10.1017/wpt.2017.17 ◽

2017 ◽

Vol 5 (1) ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Tommaso Campi ◽

Silvano Cruciani ◽

Valerio De Santis ◽

Francesca Maradei ◽

Mauro Feliziani

Keyword(s):

Magnetic Field ◽

Electric Vehicle ◽

Wireless Power Transfer ◽

Power Transfer ◽

Automotive Applications ◽

Wireless Power ◽

Safety Standards ◽

Charging System ◽

Weak Points ◽

The Magnetic Field

This paper deals with the shielding of the magnetic field generated by two planar coils of a wireless power transfer (WPT) system at the frequency of tens of kilohertz used in automotive applications. Different shielding techniques using conductive and magnetic materials are examined and discussed highlighting strong and weak points of each other. Finally, the proposed shielding configuration consisting of a combined conductive and magnetic material is applied to model an electric vehicle equipped with a WPT charging system. With this configuration, compliance with the electromagnetic field safety standards can be achieved inside (passengers) or near (pedestrian) the car.

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In vitro exposure system using magnetic resonant coupling wireless power transfer

Wireless Power Transfer ◽

10.1017/wpt.2014.12 ◽

2014 ◽

Vol 1 (2) ◽

pp. 97-107 ◽

Cited By ~ 5

Author(s):

Kohei Mizuno ◽

Junji Miyakoshi ◽

Naoki Shinohara

Keyword(s):

Magnetic Field ◽

Cell Culture ◽

Wireless Power Transfer ◽

Reference Level ◽

Power Transfer ◽

Wireless Power ◽

Exposure System ◽

Resonant Coupling ◽

In Vitro Exposure

Wireless power transfer (WPT) technology using the resonant coupling phenomenon has been widely studied. However, possible relationships between WPT exposure and human health have not been experimentally evaluated. In this study, we developed a new in vitro exposure system to evaluate the biological effects of magnetic resonant coupling WPT. The WPT was carried out using a self-resonant helical coil, which was designed to transfer the power with 85.4% efficiency at a 12.5 MHz resonant frequency. The magnetic field at the positions of the cell culture dishes is approximately twice the reference level for occupational exposure as stated in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. The specific absorption rate (SAR) at the positions of the cell culture dishes match the respective reference levels stated in the ICNIRP guidelines. In this paper, the coil design for the magnetic resonant coupling in the in vitro exposure system and characteristics, such as power transfer efficiency, electric field and magnetic field distributions, and SAR of the exposure system, are described.

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Optimization of the Alignment Method for an Electric Vehicle Magnetic Field Wireless Power Transfer System Using a Low-Frequency Ferrite Rod Antenna

Energies ◽

10.3390/en12244689 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4689 ◽

Cited By ~ 4

Author(s):

Jae Yong Seong ◽

Sang-Sun Lee

Keyword(s):

Magnetic Field ◽

Electric Vehicle ◽

Low Frequency ◽

Wireless Power Transfer ◽

International Electrotechnical Commission ◽

Power Transfer ◽

Wireless Power ◽

Optimal Arrangement ◽

Positioning Method ◽

Secondary Device

The establishment of international and regional standards for electric vehicle (EV) magnetic field wireless power transfer (MF-WPT) systems started in 2010 by the Society of Automotive Engineers (SAE). In the meantime, the EV MF-WPT standardization has been focused on primary device and secondary device topology. Recently, the International Organization for Standardization (ISO), the International Electrotechnical Commission (IEC), and SAE have begun describing the communication and alignment techniques for EV MF-WPT. In this paper, we present a fine positioning method using a low-frequency (LF) signal, as mentioned in IEC 61980 and SAE J2954. Through modeling and simulation, we optimized a LF ferrite rod antenna (FRA) for EV MF-WPT fine positioning. We also found the optimal arrangement of LF-FRAs on primary device and secondary device Finally, we used a test bench to experiment and check the results of our proposal.

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