Research & Development

    EMC Measurement Methods for High-Voltage Vehicle Components

    Using dummy loads for engines

    Engine loads are difficult to execute inside anechoic chambers for EMC tests on drive inverters. Instead we use a passive dummy load (developed by EMC Test NRW) which serves to imitate electrical impedance of three-phase motors. This enables us to install measuring equipment quickly inside anechoic chambers or shielded rooms, thus increasing efficiency.  

     

    Fig. 1: on the left, dummy loads for magnetic field measurements; on the right: CISPR 25 measurement of radio disturbance between engine and dummy load

    Using dummy loads for traction batteries

    In order to measure high-voltage components, you first need DC voltage supply. Then you interconnect a battery dummy load between the high-voltage component and the voltage supply to adapt its electrical impedance to that of a regular lithium-ion battery. This facilitates proper emissions tests leading to an increase in safety when the components are later integrated.

    Emissions tests for power electronic devices in dynamic operating states

    Compliance assessments usually rely on steady operating states. But in emissions tests, we regularly see that the operating state affects the result significantly. Special control software enables us to measure the effect of dynamic states on the emissions of inverters.

    Fig. 2

    Assessing shielding effectiveness of high-voltage cables and connectors

    We use shielded HV cables and appropriate connectors to decouple 12V and high-voltage vehicle systems. Via the twin-lead cable procedure, we can evaluate their shielding effectiveness. The benefit here is that we not only measure their shielding effectiveness but can also detect potential weaknesses in the test specimen. EMC Test NRW offers flexible adjustments for various connectors, thus enabling comprehensive EMC compliance for these components.

    Fig. 3

     

    Current Research Projects

    Inductive Vehicle 2 Grid

    • Project partner: University of Wuppertal
    • Project sponsor: Central Innovation Programme for small and medium-sized enterprises (ZIM)
    • Project duration: 2017 until 2020

    During the course of this project, EMC Test develops and analyses EMC testing methods for inductive charging systems for electric vehicles.  We focused on developing test peripherals that can measure charging stations and vehicles individually. Concerning EMC compliance for inductive charging systems, emissions are a contentious matter. We designed a replica of a car body and a filtered charging station specifically for charging station and vehicle assessments (see fig. 2).


    Fig. 4: on the left, assembling magnetic field measurement; on the right, effect of filter in inductive charging stations

     

    AFFiancE: adaptable vehicle architecture for automated vehicles

    <link www.efre.nrw.de/&gt;

    </link>

    • Project partner: Aptiv, TU Dortmund University, University of Wuppertal, IQZ
    • Project sponsor: EFRE.NRW
    • Project duration: 2018 until 2022

    Our project AFFiancE is currently looking into automated features affected by environmental conditions. Against this backdrop,, our project partner Aptiv is developing a central controller and a testing platform that enable the assessment of different features in driverless vehicles. EMC Test NRW is examining the effect of electromagnetic disturbances on sensor systems and communication within the autonomous vehicle. Due to extensive environmental sensors, the data traffic in these vehicles is significant, but—thanks to 2-wire Ethernet communication—manageable. EMC Test NRW checks how susceptible to interferences these communication systems actually are and identifies potential weak spots. They furthermore examine the effect of these disturbances on actual automated driving datasets in order to emulate these effects on Aptiv’s testing platform.

      Fig. 5: above, data rate on disturbance pulse;
    below, test set-up with interference injection via capacitive coupling clamp

    RobKom: Robust communication in electric self-driving vehicles

     <link vdivde-it.de/de&gt;

    </link><link www.bmbf.de/&gt;

    </link>

    • Project partner: NXP, TU Dortmund University, Robert Bosch GmbH, SiL, RWTH Aachen University, AiX Control
    • Project sponsor: VDI/VDE/IT and BMBF (Federal Ministry of Education and Research)
    • Project duration: 2018 until 2021 (possible extension to 2022)

     

    The project RobKom explores the EMC of autonomous vehicles. Increased interference potential in the driver system components and strict requirements regarding immunity for the communication systems in automated driving features pose challenges for EMC. The project is, thus, looking into the question of how to reduce unwanted emissions by using specific input procedures on optimised power electronics. It also monitors the coupling between communication and high-voltage vehicle systems to identify potential areas of improvement and increase interference immunity. EMC Test NRW measures emissions from the source of interference and analyses the immunity of the communication and the system coupling. In cooperation with the project consortium, a demonstrator model with optimised EMC features will be built and tested in the lab at the end of this project.

     Fig. 6: above, overcoupling of disturbances in HV systems on parallel wires; below, model demonstrator

     

     

    Completed Research Projects

    E-Keep-ULIS: Emulator concept for energy efficient and parameterisable analyses of charging infrastructure and components; implementing a vehicle-to-grid and parameterisable emulator concept
    • Project partner: Scienlab GmbH, University of Duisburg-Essen
    • Project sponsor: Central Innovation Programme for small and medium-sized enterprises (ZIM)
    • Project duration: 01 September 2014 until 31 March 2017

    During the course of this project, the consortium developed a test environment that—for the first time ever—enabled comprehensive tests on charging stations and vehicles. This environment emulates the missing counterpart when it comes to power as well as communication. It is available in the EMC Test NRW lab and generates an output of up to 150 kW (click here for further information on test environments for charging stations).

     Fig. 7: on the left, test set-up electric vehicle; on the right test set-up charging station

     

    ZAESAR: Reliable integration of electric vehicles into future smart home infrastructures
    • Project partner: TU Dortmund University, TÜV Informationstechnik GmbH, ASL Services
    • Project sponsor: Progres.nrw
    • Project duration: 04 July 2013 until 30 September 2015

     

                                                                                                   Fig. 8: set-up for conducted emissions tests

    TIE.IN: technology and test platform for a centre of excellence for interoperable E-mobility, infrastructure, and nets
    • Project partner: TU Dortmund University, TÜV Informationstechnik GmbH, ASL Services
    • Project sponsor: Progres.nrw
    • Project duration: 17 May 2011 until 31 July 2015

    Fig. 9: set-up for screening attenuation

    Contact

    Emil-Figge-Str. 76 • D-44227 Dortmund
    Phone: +49 231 / 97 42-750
    service@emc-test.de