Receivers could promote more widespread wireless recharging

According to NCSU, WPT systems hold promise for charging electric vehicles, electronic devices and other technologies.

Researchers have shown that it is possible to transmit power wirelessly by using magnetic resonance but minor changes in how the transmitter or receiver is tuned can result in faulty power transmission.

A new prototype developed at NC State is said to address the problem by automatically — and precisely — re-tuning the receivers in WPT systems. The researchers focused on receivers because methods already exist that allow researchers to use electronics to precisely tune the transmitters.

‘We’re optimistic that this technology moves us one step closer to realising functional WPT systems that can be used in real-world circumstances,’ said Dr Srdjan Lukic, an assistant professor of electrical and computer engineering at NC State and co-author of a paper on the research.

In a statement, NCSU said that WPT systems work by transmitting magnetic waves on a specific frequency from a transmitter to a receiver. These magnetic waves interact with a coil in the receiver to induce an electric current. If the coil is tuned so that its resonant frequency matches the frequency of the magnetic waves, the current it produces is amplified. However, if the receiver and the transmitter are out of tune, the system becomes inefficient and doesn’t transfer a significant amount of power. The receiver coil still picks up a trace amount of current, but it is not amplified.