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This article describes a study of magnetic field exposure in electric vehicles (EVs). The magnetic field inside eight different EVs (including battery, hybrid, plug-in hybrid, and fuel cell types) with different motor technologies (brushed direct current, permanent magnet synchronous, and induction) were measured at frequencies up to 10 MHz. Three vehicles with conventional powertrains were also investigated for comparison. The measurement protocol and the results of the measurement campaign are described, and various magnetic field sources are identified. As the measurements show a complex broadband frequency spectrum, an exposure calculation was performed using the ICNIRP “weighted peak” approach. Results for the measured EVs showed that the exposure reached 20% of the ICNIRP 2010 reference levels for general public exposure near to the battery and in the vicinity of the feet during vehicle start-up, but was less than 2% at head height for the front passenger position. Maximum exposures of the order of 10% of the ICNIRP 2010 reference levels were obtained for the cars with conventional powertrains.
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... Interest in measuring the MF in cars is generally growing, which is due to the development of electric transportation with hybrid or electric motors. There are studies in which the authors compare the levels of MFs created in cars and other types of electric vehicles [Halgamuge et al., 2010], or the levels of MFs generated by different car engines: diesel, gasoline, and electric [Vassilev et al., 2014;Hareuveny et al., 2015]. In the latter work, it was mentioned that the MF of 30 Hz and above, averaged over the entire car interior and estimated under various driving modes, had the lowest intensity for diesel cars (0.02 μT), higher for gasoline (0.04-0.05 μT), and the highest for hybrids (0.06-0.09 μT). ...
... In Tell and Kavet [2016], the recorded peaks were in the frequency range of 1.5-2.5 kHz. In Vassilev et al. [2014], it is noted that traction currents make the largest contribution to the MF (up to 300 μT) inside electric cars in the frequency range of up to 10 kHz. ...
... The goal of most publications on MFs in cars is to measure the vehicle's own fields at different points in the passenger compartment and to correlate the measured data with electromagnetic standards in the frequency range from 10 Hz and above [Halgamuge et al., 2010]. Although in recent years there have been studies in which MF measurements are taken while driving around the city in an electric car, those studies have no analysis of MF changes in the frequency range of less than 10 Hz [Vassilev et al., 2014;Yang et al., 2019]. ...
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In this study, we measured and analyzed the spectral characteristics of a low‐frequency magnetic field (MF) inside several gasoline‐powered cars while driving on busy city roads. The spectra obtained upon measurements in the interior of the cars are compared with those measured in office locations at different times of the day and with different disturbances of the geomagnetic field (k‐index of disturbance 2–8). The power spectral density of the electromagnetic field in cars moving on busy roads in the frequency range of 10−3–102 Hz is one to three orders of magnitude higher than that in urban offices. This raises a question regarding the possible influence of these MFs on the psychophysiological state of drivers. In turn, in the daytime, the MF power in the range from 10−3 to 1 Hz inside the locations is three times higher compared with the power of a strong geomagnetic storm. Despite such an overwhelming magnetic background, geomagnetic storms affect various organisms. The nonspecific effect of magnetic storms is supposed to be associated with relatively long (lasting several hours or more [frequency range of 10−4−10−5 Hz]) periods of enhancement or weakening of the local geomagnetic field. In this range, especially at night, the power spectral density of geomagnetic disturbances is comparable to and can even exceed the power density of urban MFs.
... The roller test-bench enabled programmed simulation of dynamic driving resistances encountered in real life. Additionally, the roller-bench facilitates safe, standardised and reproducible test cycles with maximal acceleration and deceleration protocols; essential to obtain maximal engine torque and subsequent maximal electromagnetic field generation [32]. ...
... The main source of the electromagnetic field generated by electric cars is the battery, though there is contribution from the power inverters, wiring, and power steering pumps [32,38]. Differences in location of the battery and of other source components are the likely explanation for the variation of the electromagnetic field around the cars. ...
... More potentially clinically-relevant exposures occurred during charging; the observed values were consistent with previous studies [32]. A plausible explanation for the higher values is that the charging cable is less shielded. ...
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Background: Electric cars are increasingly used for public and private transportation and represent possible sources of electromagnetic interference (EMI). Potential implications for patients with cardiac implantable electronic devices (CIED) range from unnecessary driving restrictions to life-threatening device malfunction. This prospective, cross-sectional study was designed to assess the EMI risk of electric cars on CIED function. Methods: One hundred and eight consecutive patients with CIED presenting for routine follow-up between May 2014 and January 2015 were enrolled in the study. The participants were exposed to electromagnetic fields generated by the four most common electric cars (Nissan Leaf, Tesla Model S, BMW i3, VW eUp) while roller-bench test-driving at Institute of Automotive Technology, Department of Mechanical Engineering, Technical University, Munich. The primary endpoint was any abnormalities in CIED function (e.g. oversensing with pacing-inhibition, inappropriate therapy or mode-switching) while driving or charging electric cars as assessed by electrocardiographic recordings and device interrogation. Results: No change in device function or programming was seen in this cohort which is representative of contemporary CIED devices. The largest electromagnetic field detected was along the charging cable during high current charging (116.5 μT). The field strength in the cabin was lower (2.1-3.6 μT). Conclusions: Electric cars produce electromagnetic fields; however, they did not affect CIED function or programming in our cohort. Driving and charging of electric cars is likely safe for patients with CIEDs.
... Conventional gasoline engines generate much weaker fields than electric propulsion systems. Vassilev et al. (2015) measured fields in various positions within eight electric or hybrid and three conventional vehicles under various driving conditions using equipment that captured magnetic fields from DC to the MHz region. They quote maximum measured fields from electric propulsion currents of 100-300 μT (0-10 kHz), wheels of 0.2-2 μT (0-20 Hz), steering pumps of about 1 μT (0.5-1 kHz), and internal combustion engines of 50-150 nT (0-200 Hz). ...
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Modern transportation systems are integrated in the urban fabric and next to populated centers. For this reason the assessment of the impact in terms of electrical and electromagnetic emissions is quite relevant: stray current, touch voltage, human exposure and interference to implantable devices. Standards, regulations and reference scenarios are quite articulated and should be comprehensively and accurately addressed in the contractual specifications and at the preliminary design stage of transportation projects. To this aim this work considers relevant standards, typical phenomena and system assurance elements to define comprehensively and unambiguously the most important interfaces, avoiding the typical pitfalls of generic statements and common misunderstandings.
... Due to the electrification of vehicles, magnetic stray fields are increasingly present. For example in [2], magnetic fields of several hundreds of µT were measured in electric vehicles, and traced to traction currents. Such level of stray field would corrupt any accurate magnetic sensor measurement if left unmitigated. ...
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... Presently, progress has been made in theoretical and experimental research on MG, and MG has been applied in various fields such as wind turbines [7,8], electric vehicles [9,10], and ship propulsion. In recent years, MG can transfer as much torque as mechanical gears. ...
... 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]. ...
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The expected imminent widespread use of electromobility in transport systems draws attention to the possible effects of human exposure to magnetic fields generated inside electric vehicles and during their recharge. The current trend is to increase the capacity of the battery inside the vehicles to extend the available driving range and to increase the power of recharging columns to reduce the time required for a full recharge. This leads to higher currents and potentially stronger magnetic fields. The Interoperability Center of the Joint Research Center started an experimental activity focused on the assessment of low-frequency magnetic fields emitted by five fast-charging devices available on the market in recharge and standby conditions. The aim of this study was to contribute to the development of a standard measurement procedure for the assessment of magnetic fields emitted by direct current charging columns. The spectrum and amplitudes of the magnetic field, as well as exposure indices according to guidelines for the general public and occupational exposure, were recorded by means of a magnetic field probe analyzer. The worst-case scenario for instantaneous physical direct and indirect effects was identified. Measurements within the frequency range of 25 Hz-2 kHz revealed localized magnetic flux density peaks above 100 μT at the 50 Hz frequency in three out of five chargers, registered in close proximity during the recharge. Beyond this distance, exposure indices were recorded showing values below 50% of reference levels. Bioelectromagnetics. © 2020 Bioelectromagnetics Society.
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