Compliance Assessment of the Spatial Averaging Method for Magnetic Field Leakage from a Wireless Power Transfer System in Electric Vehicles
Abstract
:1. Introduction
2. Related Studies
2.1. Evaluation of Leaked Magnetic Field
2.2. Computational Dosimetric Study for EV WPT Systems
2.3. Exposure Assessment Method for Nonuniform Magnetic Field
2.4. Comparison of Exposure Assessment in Human Exposure Inside and Outside the Vehicle
3. Models and Methods
3.1. Human Body Models
3.2. Exposure Scenarios
3.3. Computational Methods
3.4. Compliance Assessment Procedure
4. Results
4.1. Distribution of Magnetic Field Outside and Inside the Vehicle
4.2. Internal Electric Field in the Human Body
4.3. Assessment with Spatial Averaged Magnetic Field Outside the Vehicle
4.4. Correlation between Emax and Have Inside the Vehicle Made of CFRP
4.5. Assessment with Spatial Averaged Magnetic Field Inside the Vehicle
5. Discussion
6. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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(a) | ||||||
Year | 2015 [19] | 2017 [40] | 2018 [41] | 2022 [43] | ||
Considered exposure scenario | Standing near to a vehicle model. | Standing 650 mm away from coils. | Standing near the coil, human-coil distance is 235 mm *. | Standing near to a vehicle mimic steel plate *. | ||
Operating frequency [kHz] | 85 | 85 | 125 | 85 | ||
Transferred power [kW] | 7 | 7 | 7.7 | 7.7 | ||
Exposed magnetic field strength (max) [A/m] | 56.7 excluding the region under the vehicle | N/A | 28 | N/A | ||
Maximum electric field [V/m] | 0.4 (ankle) | N/A | 0.42 (leg) | N/A | ||
Coupling factor [44] for the ICNIRP guidelines [V/A] | 0.013 (99.9th percentile) | 0.038–0.054 ** for different coil positions of a vehicle model | 0.027 (averaged over 2 × 2 × 2 mm3 cube and 99.9th percentile) | 0.018 (99.9th percentile) | ||
(b) | ||||||
Year | 2018 [36] | 2019 [20] | 2020 [38] | |||
Considered exposure scenario | driving passenger. | driving passenger and other passenger. | driving passenger. | |||
Operating frequency [kHz] | 85 | 85 | 85 | |||
Transferred power [kW] | 7.7 | 3.7 | 3.7 | |||
Exposed magnetic field strength (max) [A/m] | 347.4 | 16.3 (driver’s buttocks) 23.6 (passenger’s feet) | 46.5 | |||
Maximum electric field [V/m] | 19.9 (feet) | 0.53 (driver’s buttocks) 0.35 (passenger’s feet) | 0.61 (buttocks) | |||
Coupling factor [44] for the ICNIRP guidelines [V/A] | 0.105 (averaged over 2 × 2 × 2 mm3 cube) | 0.060 (driver) 0.027 (passenger) (99.9th percentile) | 0.024 (averaged over 2 × 2 × 2 mm3 cube and 99.9th percentile) |
Definitions | Heights from The Ground [m] | Heights from The Floor [m] |
---|---|---|
1: TR 62905 | 0.5, 1.0, 1.5 | 0.5, 1.0, 1.2 |
2: Maximum point + PAS 63184 | 0.06, 0.5, 1.0, 1.5 | 0.1, 0.5, 1.0, 1.2 |
3: Every 25 cm from maximum point | 0.06, 0.31, 0.56 | 0.1, 0.35, 0.6 |
(a) | |||||
Setting | Magnetic Field Strength [A/m] | ||||
Measurement Points | Have | ||||
Definition 1 | 0.5 m | 1.0 m | 1.5 m | - | 0.40 |
0.78 | 0.28 | 0.13 | |||
Definition 2 | 0.06 m | 0.5 m | 1.0 m | 1.5 m | 0.68 |
1.54 | 0.78 | 0.28 | 0.13 | ||
Definition 3 | 0.06 m | 0.31 m | 0.56 m | - | 1.15 |
1.54 | 1.23 | 0.67 | |||
(b) | |||||
Setting | Magnetic Field Strength [A/m] | ||||
MeasurementPoints | Have | ||||
Definition 1 | 0.5 m | 1.0 m | 1.5 m | - | 0.41 |
0.82 | 0.27 | 0.13 | |||
Definition 2 | 0.06 m | 0.5 m | 1.0 m | 1.5 m | 0.69 |
1.55 | 0.82 | 0.27 | 0.13 | ||
Definition 3 | 0.06 m | 0.31 m | 0.56 m | - | 1.18 |
1.55 | 1.27 | 0.72 |
(a) | |||||
Setting | Magnetic Field Strength [A/m] | ||||
Measurement Points | Have | ||||
Definition 1 | 0.5 m | 1.0 m | 1.2 m | - | 0.015 |
0.015 | 0.017 | 0.013 | |||
Definition 2 | 0.1 m | 0.5 m | 1.0 m | 1.2 m | 0.013 |
0.009 | 0.015 | 0.017 | 0.013 | ||
Definition 3 | 0.1 m | 0.35 m | 0.6 m | - | 0.012 |
0.009 | 0.011 | 0.016 | |||
(b) | |||||
Setting | Magnetic Field Strength [A/m] | ||||
Measurement Points | Have | ||||
Definition 1 | 0.5 m | 1.0 m | 1.2 m | - | 0.40 |
0.94 | 0.15 | 0.11 | |||
Definition 2 | 0.1 m | 0.5 m | 1.0 m | 1.2 m | 1.25 |
3.81 | 0.94 | 0.15 | 0.11 | ||
Definition 3 | 0.1 m | 0.35 m | 0.6 m | - | 2.14 |
3.81 | 2.03 | 0.60 |
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Okada, M.; Miwa, K.; Kodera, S.; Hirata, A. Compliance Assessment of the Spatial Averaging Method for Magnetic Field Leakage from a Wireless Power Transfer System in Electric Vehicles. Appl. Sci. 2024, 14, 2672. https://doi.org/10.3390/app14072672
Okada M, Miwa K, Kodera S, Hirata A. Compliance Assessment of the Spatial Averaging Method for Magnetic Field Leakage from a Wireless Power Transfer System in Electric Vehicles. Applied Sciences. 2024; 14(7):2672. https://doi.org/10.3390/app14072672
Chicago/Turabian StyleOkada, Masanori, Keishi Miwa, Sachiko Kodera, and Akimasa Hirata. 2024. "Compliance Assessment of the Spatial Averaging Method for Magnetic Field Leakage from a Wireless Power Transfer System in Electric Vehicles" Applied Sciences 14, no. 7: 2672. https://doi.org/10.3390/app14072672