US project develops fast, efficient wireless charger
The project, run by the Department of Energy’s Oak Ridge National Laboratory (ORNL), has partnered with Toyota, Cisco Systems, Evatran and Clemson University International Center for Automotive Research to design and build a fast charging system with no need to directly plug the car in.
Designed in-house, ORNL’s wireless charging system transmits energy over short distances from a pad on the ground to a receiver on the car, and is now said to be close to market. It offers a 2okw charge at 90% efficiency – a large advance on the 6.9kW at 85% efficiency achieved beforehand – while charging an adapted Toyota RAV4 EV in the laboratory,
The next target is 50kW charging, which the same power output as a DC rapid charger, and safety aspects of the high-frequency magnetic fields generated by the technology are among the main considerations.
David Smith, vehicle systems program manager, said: “Wireless power transfer is a paradigm shift in electric vehicle charging that offers the consumer an autonomous, safe, efficient and convenient option to plug-in charging. The technology demonstrated today is a stepping stone toward electrified roadways where vehicles could charge on the go.”