Wireless Charging Gets Big Boost


As the technology turns, newer technology can help create further improvements in technology, allowing electric cars to wirelessly recharge while they are on the highway.

The objective of the high efficiency charging system is to increase the range of electric cars and trucks. This would be achievable using an all-electric highway through the use of magnetic fields to transfer large electric currents between coils placed several feet part.

According to Shanhui Fan, Associate Professor of Electrical Engineering at Stanford University, “Our vision is that you’ll be able to drive onto any highway and charge your car. Large-scale deployment would involve revamping the entire highway system and could even have applications beyond transportation.”

With a new wireless charging system, this can address a major limitation for plug-in electric cars. This limitation is the limited driving range, allowing for short trips and long charging times. One popular electric car in the market today is the Nissan Leaf, whose range is a hundred miles on a single charge and a charge while driving system can make using electric cars all the more accessible.

The study’s co-author, Richard Sassoon, Managing Director of the Stanford Global Climate and Energy Project, “What makes this concept exciting is that you could potentially drive for an unlimited amount of time without having to recharge. You could actually have more energy stored in your battery at the end of your trip than you started with.”

The technology is based on the science of magnetic resonance coupling. In this set up, two copper coils are set to resonate with one another at the same natural frequency, similar to two wine glasses that vibrate on a specific note played. These coils would be placed a few feet apart, where one coil would be connected to an electric current. This in turn generates a magnetic field that then causes the second coil to resonate. This resonance would result in the invisible transfer of electrical energy through the air from one coil to the other.

According to the researchers, “Wireless power transfer will occur only if the two resonators are in tune. Objects tuned at different frequencies will not be affected.”

Back in 2007, Massachusetts Institute of Technology researchers used magnetic resonance to power a sixty-watt bulb. This experiment showcased how the power can be transferred between stationary coils separated six feet apart, even when other obstacles are put between the two coils. This is very important in terms of safety and reliability for users. As a result, MIT researchers have created technology that allows wireless transfer of electricity for a stationary object, such as a car parked on the street or in the garage.

Fan and his team hopes if this technology developed in MIT can be pushed further to allow transfer of ten kilowatts of electrical power over a distance of six and a half feet. This would enable electric cars to be charged on the highway, even in motion. This can even be an additional boost for the acceleration or other difficult terrain.

This projected system would be through a series of coils embedded in the road while the receiving coils would be in the bottom of the car that resonates in the same frequency as it travels, creating the magnetic fields that would transfer the electrical energy to recharge the battery.