High-resolution magnetic-field exposure simulations of automotive inductive power-transfer systems using a scaled-frequency finite difference time domain approach with multi-GPU acceleration

Inductive power transfer technology enables, eg, wireless charging of electric and hybrid vehicles. Proposed systems generally consist of at least 2 geometrically separated loosely coupled air-cored coils. The charging process at operating frequencies from 80 to 140kHz potentially exposes humans. The computational simulation of low frequency fields combined with lossy dielectric distributions in such scenarios requires nonstandard numerical approaches. As long as quasi-static assumptions are valid, the scaled-frequency finite difference time domain method is suitable for such problems. With additional considerations to the original approach from Gandhi and Chen, based on work from Kaune and Gilles, simulations may include anatomical body models as well as thin metallic sheets, which are quite common in automotive scenarios with thicknesses of 1 to 1.2mm.