Computational dosimetry for wireless charging of an electrical vehicle

Recent advances in wireless power transmission have enabled various new applications, one of which is wireless charging of an electrical vehicle. In this application, electric power is wirelessly transmitted using strong electromagnetic fields from a coil located on the ground to another coil attached to the vehicle. In this study, we use computational modelling to investigate the human exposure to the electromagnetic fields of such a wireless charging system. The transmitted power is 7 kW and the frequency of power transmission is 85 kHz. The strengths of the external magnetic field around the vehicle and the electric field induced in the human body are compared with the exposure limits set in the international human exposure guidelines. It is found that the magnetic field strength near the vehicle exceeds the allowable field limits of international guidelines. However, the electric fields that are induced in the human body are well below the exposure limits. Therefore, kW-class wireless charging of an electrical vehicle seems to be feasible for general public use from the point of view of human exposure.

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