GPU-Based Near Real-Time Estimation of the Human Body Penetrating Low-Frequency Magnetic Fields Using Free-Space Field Measurements

Wireless power transfer (WPT) systems can be utilized to advance electromobility, especially in local public transport. These systems emanate low-frequency stray magnetic fields that expose living beings in the vicinity and induce potentially harmful electric fields into the exposed biological tissues. To ensure personal protection, International Commission on Non-Ionizing Radiation Protection (ICNIRP) has established basic restrictions on the body-internal electric field strength that should not be exceeded. Since this field strength cannot be measured, numerical schemes such as the scalar-potential finite-difference (SPFD) scheme need to be utilized to determine the induced body-internal electric field distribution. This numerical scheme allows a near real-time body-internal electric field determination but requires as input a fine sampling of the magnetic flux distribution in the domain of potential human exposure. The works’ objective is to provide a component for deriving the large number of required magnetic flux densities from free-space field measurements in near real-time, required for direct body-internal electric field determinations in real exposure assessment environments. By applying a highly parallelized approximation procedure using radial basis functions (RBFs) on NVIDIA graphics processing units (GPUs), the required magnetic flux densities for different human voxel models with an ICNIRP-recommended edge length of 2 mm can be derived in a few milliseconds.