4WD-drivetrain testbench

One for All Challenges

Testbenches for the automotive industry of today have to fulfill more and higher requests in comparison to the past. The testruns become more complex and they have to simulate the real driving conditions as exactly and reproducably as possible.

For measuring real CO2- and emissions-values , fuel consumptions and/or electricity consumption values the European Union developed the new test procedure WLTP (world wide light duty transient procedure) which is fixed in the legislative since September of 2018 for new passenger car homologation. It replaces the former NEDC-cycle (new European driving cycle) to be the new basis for the official type approval of new passenger cars.

ElringKlinger Motortechnik introduced a new and modern 4WD-drivetrain testbench in order to fulfill the new demands of the clients respecting all the restrictions of the WLTP-legislation and of the new real driving emissions legislation (RDE). This testbench offers a significant higher power potential and higher flexibility for all sorts of test runs.

Because of the rising innovation pressure time slots to realize a full development process until readiness for series production have been becoming significantly smaller. The rising complexity of drivetrain components including their electronic management and the cumulationg interaction of various ECU´s for engine, gearbox and hybrid drive – may be in combination with an intelligent driver assistant system – make it necessary to have an early validation of the total drivetrain even when the first prototype vehicle is not available and not ready yet.

Multi Configuration Testbench for a Wide Spectrum of Investigations

On the new 4WD-testbench test with high accuracy, dynamic, flexibility for all sorts of drivetrains can be performed. The testbench covers combustion engines, hybrid drives (combustion engines combined with electric motors in a serial or parallel configuration) range extender configurations, fuel cell drives as well as pure electric drives.

Beside the single component testing of the combustion engines, gearboxes, electric motors and batteries especially control strategies for the interaction of the various hybrid components can be tested, optimized and evaluated. Hence, for the development of different drivetrain concepts only one testbench installation is needed.

The feature-catalogue of the testbench includes:

  • testing and optimizing of vehicle drivetrains
  • gearbox investigations and optimization of hybrid gearshift strategies
  • vehicle measurements – in steady state speed/load-points as well as in WLTC and RDE cycles
  • simulation of the overall driving dynamic including breaking events and break energy recuperation
  • cold testing down to -10°C with short time re-cooling and re-conditioning of the ambient air, oil- and water-circuit (6 WLTC´s per day can be carried out)

State of the Art Equipment

The equipment of the new drivetrain testbench was chosen in accordance to the special demand of the automotive industry.

  • 4 asynchronous machines for breaking the wheels directly. Of course all tests can be performed for front-, rear- and all-wheel-drives
  • the performance data are 433 KW / 3400 Nm / 1200 rpm for each asynchronous machine
  • the inertia of every machine is 3,57 kgm2. The maximum current is 709 amp. All machines can be overloaded with a factor of 1,2
  • the testbench is equipped with one of the most efficient and open automation systems. It is a Morphee-system with fast Ethercat data transfer. The software is featuring all functions which can used for complex drivetrain testing – simply manually controlled tests as well as automated driven dynamic tests
  • for controlling the asynchronous machines an OPV-controller was installed which is able to perform real time calculations up to 4 KHz
  • various additional support functions can be implemented by tools like Matlab/Simulink, AMESim(3), GT-Suite(3), DYmola(3) and C/C++
  • the open integration- and test-platform X-Mod (FEV) enables testruns with intelligent vehicle- and driver-models as well as highly flexible models for simulation the traffic on the road. The simulation of complete and absolutely realistic test scenarios can be done; it is the first time that the on road testing of a vehicle can be transferred back to the testbench
  • on the testbench a wind machine upt o 140 km/h and a battery simulator device (48 -1000 V) is installed. As mentioned above the ambient temperatures can be exactly adjusted in a range from -10°C to 40°C. A cooling system with a power of 200 KW is used.
  • the testbench ha interfaces to all emission measurement devices such as AVL-FTIR, AVL-AMA, Horiba, CVS-System, PN-counter and PM-measurement system.

ElringKlinger Motortechnik offers this testbench for highly challenging testing and development tasks in order to accelerate future developments and to give the clients a solid advantage in development time and accuracy.