Characterization of Extremely Low Frequency Magnetic Fields from Diesel, Gasoline and Hybrid Cars under Controlled Conditions

Abstract

This study characterizes extremely low frequency (ELF) magnetic field (MF) levels in 10 car models. Extensive measurements were conducted in three diesel, four gasoline, and three hybrid cars, under similar controlled conditions and negligible background fields. Averaged over all four seats under various driving scenarios the fields were lowest in diesel cars (0.02 μT), higher for gasoline (0.04–0.05 μT) and highest in hybrids (0.06–0.09 μT), but all were in-line with daily exposures from other sources. Hybrid cars had the highest mean and 95th percentile MF levels, and an especially large percentage of measurements above 0.2 μT. These parameters were also higher for moving conditions compared to standing while idling or revving at 2500 RPM and higher still at 80 km/h compared to 40 km/h. Fields in non-hybrid cars were higher at the front seats, while in hybrid cars they were higher at the back seats, particularly the back right seat where 16%–69% of measurements were greater than 0.2 μT. As our results do not include low frequency fields (below 30 Hz) that might be generated by tire rotation, we suggest that net currents flowing through the cars’ metallic chassis may be a possible source of MF. Larger surveys in standardized and well-described settings should be conducted with different types of vehicles and with spectral analysis of fields including lower frequencies due to magnetization of tires.

Passenger Exposure to Magnetic Fields due to the Batteries of an Electric Vehicle

“…Content may change prior to final publication. VT-2015-00294.R1 7 conventional vehicles is caused by the permanent magnetization of steel belted tires, whose rotating speed determines the fundamental frequency of the corresponding MF (usually up to 15-20 Hz) [7,8]. Additionally, vehicle construction such as bodyshell shape, thickness and materials may have a significant impact on in-vehicle MF levels [16].…”

“…Most of these works are based on real in-vehicle measurements (some of them under dynamic driving conditions), while others use numeric simulation. For instance, [7] and [8] present results for 11 conventional and electric vehicles and 10 conventional and hybrid vehicles, respectively. On the other hand, finite element simulations are used in [15][16][17] to analyze the MF threat and to assess the effectiveness of certain mitigation measures (power devices positioning and magnetic shielding).…”

“…The study in [11] focuses on the batteries and the DC/DC converter, akin to the scope of this paper. Similarly, there are a few recent studies regarding EMFs and health issues in hybrid and EVs [5][6][7][8][14][15][16][17]. Most of these works are based on real in-vehicle measurements (some of them under dynamic driving conditions), while others use numeric simulation.…”

“…R. Arribas works in the Electrical Engineering Department, Technical University of Madrid, SPAIN (e-mail: jaime.rodriguez@upm.es). environment in the interior of these vehicles becomes necessary [5][6][7][8]. EVs have an electric system of significant power, consisting of batteries, power converters and electric motors (besides all the connecting wires).…”

Assessment of Low‐Frequency Magnetic Fields Emitted by DC Fast Charging Columns

“…The scientific literature includes some studies regarding the electromagnetic environment inside conventional, hybrid, and EVs [Moreno‐Torres et al, 2013; Karabetsos et al, 2014; Hareuveny et al, 2015; Vassilev et al, 2015; Tell and Kavet, 2016]. The issue of human exposure to EMFs emitted during EV recharge with wireless power transfer systems is specifically addressed in the publicly available specification of the International Standard Organization ISO/PAS 19363 regarding “Electrically propelled road vehicles—Magnetic field wireless power transfer safety and interoperability requirements” [ISO, 2017].…”