Assessment of Electromagnetic Exposure Levels for Humans from Electric Vehicle DC Charging Stations

The potential health risks of DC charging piles to human health were investigated by quantifying the internal electromagnetic exposure level. In this study, the transformer in the DC/DC circuit of a DC charging pile was selected as the radiation source, and two realistic human models (adult and child) were used as exposure subjects. A simulation model, including the vehicle body, charging pile, and transformer, was established using COMSOL(COMSOL Multiphysics 6.2) Multiphysics software to calculate the magnetic induction intensity (B-field) and electric field intensity (E-field) in various organs at distances of 0.1 m, 0.3 m, and 0.6 m from the charging pile. The results show that at 0.1 m, the peak B-field (1.91 µT) and E-field (447 mV/m) in the adult body were 1.91% and 2.07% of the ICNIRP occupational exposure limits, respectively, and 7.07% and 4.14% of the public exposure limits. For the child model, the peak electromagnetic exposure levels (2.31 µT and 259 mV/m) were only 8.56% and 2.40% of the public limits. Further evaluation of exposure levels for in-vehicle occupants during charging showed that the peak B-field and E-field for an adult driver and a child in the front passenger seat were 0.0225 × 10^-2 µT, 0.0237 × 10^-2 µT, 5.81 mV/m, and 5.82 mV/m, respectively, far below the ICNIRP public limits. Additionally, analyses at multiple frequency bands (85 kHz, 90 kHz, and 95 kHz) under a typical scenario (adult at 0.1 m from the charging pile) revealed that the B-field in the human body decreased with increasing frequency, while the E-field showed minimal variation due to shielding effects. All electromagnetic exposure levels were below both ICNIRP public and occupational limits, indicating the broad applicability of the results. Under normal operating conditions of DC charging piles, the electromagnetic exposure from the DC/DC transformer fully complies with safety standards and poses no threat to human health. This study provides a scientific basis for alleviating public concerns about the health risks of electromagnetic radiation from DC charging piles for electric vehicles.