Wireless power transfer for EVs, mobile and medical devices

A team of researchers has discovered how efficient wireless power transfer can be achieved in the presence of complex electromagnetic environments, such as metal plates.

The team found that resonance frequency matching, alignment of the magnetic field and impedance matching are the most important factors for efficient wireless power transfer. These findings are highly significant, they say, because one futuristic application of wireless power transfer would be to harness and use it via magnetic resonance to charge electric vehicles.

Corresponding coils attached to the bottom of an electric vehicle would pick up energy as the vehicle passes over the coils embedded in the highway. With this type of dynamic charging, an electric vehicle’s driving range could become unlimited and the size of its batteries would be greatly reduced.

Wireless power transfer technology may find use in a wide range of applications beyond powering electric vehicles, said Xiaofang Yu, an electrical engineer and postdoctoral fellow at Stanford University who led the research.

Other applications may include charging mobile devices, home appliances or even medical devices implanted in the human body. The article ‘Wireless power transfer in the presence of metallic plates: Experimental Results’ by Xiaofang Yu, Torbjorn Skauli, Bjorn Skauli, Sunil Sandhu, Peter B Catrysse and Shanhui Fan appears in the the American Institute of Physics’ journal AIP Advances.

Authors of the article are affiliated with Stanford University in Palo Alto, CA; Norwegian Defence Research Establishment in Kjeller, Norway; and the German International School of Silicon Valley, Mountain View, California.