Simulation of Realistic Vehicle Battery Voltage Profiles on Hardware-in-the-Loop Test Benches

Abstract:

Driver assistance systems are designed not only to support the drivers in their general driving activities but also to be able to take over in critical situations， too. Test drives with a prototype vehicle are the most realistic way to test these systems. The test drive exposes the systems to all kinds of environmental influences and examines their reliability. Since test drives with prototypes are very costly and difficult to reproduce in the exact same way， hardware-in-the-loop （HiL） test benches are often used in the development and testing process. HiL test benches providing the relevant hardware and can also provide simulated environmental influences for these systems under test （SUT）. During test drives with real vehicles， variations in the electrical system voltage occur due to the different environmental influences. These variations are based on changing electrical loads. Currently these variations in the vehicle electrical system voltage cannot be simulated on HiL test benches. In order to identify causes and underlying phenomena of the variations， recorded data from real test drives are examined with respect to possible phenomena. These results are then used to derive a phenomenological stimulation that can be used to simulate realistic voltage curves on test benches. The paper analysis vehicle measurements with the aim of finding possible causes for the long and short-therm change of the on-board voltage. This paper presents an approach for realistic stimulation of voltage variations in the context of virtual test drives on HiL test benches.

Key words:automotive testing;hardware-in-the-loop (HiL);shift test effort to simulation;battery voltage;test drive