Determination of exposure against magnetic fields caused by electric and hybrid drive concepts - 3607S4574
urn:nbn:de:0221-2009082182 BfS-RESFOR-21/09
Summary
In recent years alternative drive systems have become key technologies in the research fields of automotive industries. Currently electro-hybrid systems and purely electric drive systems belong to the most promising technologies, which have already been deployed in (a few) presently available series vehicles by very few manufacturers. Consequently, these systems are bringing high power electric and electronic components (electric motors, inverters, batteries) in the immediate surrounding of the car’s driver and passengers. Therefore, from the view of radiation protection, the question about the personal magnetic field exposure inside the vehicles, caused by these components and the cabling between them arises.
In the frame of this project the magnetic induction was measured inside a sample of vehicles, selected from the currently available market, and was assessed according to the ICNIRP guidelines published in 1998. Additionally, the measured field values were evaluated with respect to possible electromagnetic interference with cardiac pacemakers according to the draft standard DIN VDE 0840-3-1. Categories of vehicles which were considered in this study included motorcars with hybrid drive systems (Honda Civic IMA, Toyota Prius, Lexus GS 450h), motorcars with purely electric drive systems (Panda Electric, Doblo Electric), utility vehicles (the lorry Daimler Atego BlueTec Hybrid and the PEFRA tractor model 780), as well as the bus Urbino 18 Hybrid. Following the observation that in all considered vehicles all relevant spectral components were restricted to the frequency range below approximately 80 kHz, it was decided to limit the measured frequency range to 0 Hz – 100 kHz. As the measurement quantity the magnetic induction was recorded in time domain and the recordings were assessed in a frequency selective manner. In order to avoid systematic overestimation of exposure, the assessment followed an approach which correctly considers the phase relation between the single spectral components during the summation process required to get the resulting exposure in relation to the ICNIRP-reference levels.
