Nikola Tesla created a device for wireless energy transfer using high frequency electromagnetic radio waves over 100 years ago. Ultimately, we will be using wireless transfer of energy to at least charge electric vehicles. Many researchers are proposing to power electric vehicles wirelessly giving us unlimited range. Often suggested is induction using the alternating current in one coil to induce electricity in another coil. This is the same technology that is used in transformers, like the power supply for your laptop battery. It is also used to wirelessly charge mobile devices and has been seen in wireless toothbrush chargers.
Masahiro Hanazawa at Toyota Central R&D Labs and Takashi Ohira at Toyohashi University of Technology speculate that the steel belts in tires can be used for the energy transfer and they are not using coils. Grid-supplied power is “converted into radio frequency (RF) by high-speed inverters implanted along tracks in the road. The RF voltage is applied to a balanced metal track embedded under the surface of the road. The EV picks up the RF voltage via electrical capacitance between the metal and a steel belt installed inside of the tires of the EV.”
Unlike the magnetic energy transfer of coils, RF energy uses a much higher frequency electronic circuit. These can be tuned like a radio to a specific frequency. And like radio waves, they are easily transmitted. The electrical leakage is described as “small” and infrastructure would be less expensive than using a magnetic coil system. What is unique to their research is using the steel belts of a tire as a receiver. Tesla would be proud.
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