Simulation of human body exposure to near field of high and low RF wireless power transfer systems

Abstract

In this paper, human body exposure to high frequency electromagnetic field radiated by wireless power transfer system antennas is analysed by numerical modelling using commercial software FEKO. The analysis is carried out for two simplified models of human body (parallelepiped and cylinder model) exposed to high and low frequency radiation in terms of power transfer efficiency and specific absorption rate at frequencies of 13.56 MHz, 6.78 MHz, and 100 kHz. Used simplified models are validated by comparison with realistic human body model results. It is shown in our 5-W power transfer system example that the specific absorption rate in simplified, as well as in realistic, human body model does not exceed the reference limit values prescribed by international guidelines, both for the general and for the professional population. It is also shown that there is no significant difference in specific absorption rate and power transfer efficiency while using different human body models, which is excellent because the theoretical calculations limited on simplified models can be used for human body exposure estimation.