Influence of Lossy Objects for Resonator-Coupled Type Wireless Power Transfer System with Coplanar Dual-Spiral Resonators

Reduction in Human Interaction with Magnetic Resonant Coupling WPT Systems with Grounded Loop

“…The receiver structure of the MRC-WPT system was identical to that of the transmitter [40]. The geometric parameters of the spiral resonator were determined using its self-resonant frequency and quality factor [41]. In Figure 1a, κ TR represents the coupling coefficient between the transmitter (denoted as T) and receiver (denoted as R).…”

Performance improvement of resonator-coupled wireless power transfer system using dual-spiral resonator with angular misalignments

“…The single-spiral resonator was fabricated on Styrofoam boards with a thickness of 1.0 cm, with the 1.0 cm winding pitched spiral-shaped Cu wire, the diameter of which was 1.0 mm, as presented in Figure 1a. The whole diameter of the conventional single-spiral resonator, 1 D , was 37.6 cm. For these conditions, the resonator frequency of that single-spiral resonator was just 10.0 MHz.…”

“…The dual-spiral resonators were fabricated by using polyethylene (PE) substrates with a thickness of 2.0 mm on which a 5.0 mm-pitched spiral-shape groove was drawn, and the 1.0 mm diameter Cu wire was embedded along there. The reason why the dual-spiral resonators were investigated was because it has been clarifi ed that by using dual-spiral resonators, the power transmission effi ciency of the RC-WPT system was made insensitive to lossy objects existing on the power transmission path, compared to an RC-WPT system with the conventional single-spiral resonators [1].…”

“…However, that system requires careful positioning and is restricted to short-distance power transmission use. On the contrary, the resonator-coupled type of wireless power transfer (RC-WPT) system [1] has tremendous potential for the layout-free electric power supply for some electric appliances and/or IoT systems in the near future, due to its superiority of effi cient power transmission for the middlerange distances [2][3][4]. In order to obtain good performance of an RC-WPT system, two types of spiral resonators have been used throughout this research, making a comparison between them.…”

“…In addition, to realize a widely applicable RC-WPT system, we have proposed the dual-spiral resonators presented in Figure 1b. These can avoid the infl uence of lossy objects that exist throughout the power transmission path [1,5].…”