Interaction between humans and wireless power transfer systems

The performance of wireless power transfer (WPT) systems depends on antenna radiation efficiency and operating resonant frequency. In HF WPT systems, nearby objects have a certain impact on antenna characteristics and consequently on the WPT system performance. In this paper, human-WPT system interaction is investigated in order to provide basic recommendations regarding WPT system design and the human exposure to WPT systems. Preliminary results show that an efficient WPT system with four-arm SHAs is less susceptible to the degradation of system performance due to the influence of the nearby fantom, in comparison with the inefficient WPT between spirals. Also, it is possible to achieve a smaller risk of the electromagnetic human exposure to WPT systems when using an efficient WPT system rather than an inefficient one or a standalone transmitter.