Correction algorithms for WLTP chassis dynamometer and coast-down testing

Correction algorithms for WLTP chassis dynamometer and coast-down testing

Ligterink, N.E.
van Mensch, P.
Cuelenaere, R.F.A.
Hausberger, S.
Leitner, D.
Silberholz, G.

2015

The flexibilities allowed in the WLTP are necessary to allow efficient testing without having a lot of invalid tests. Nevertheless some of the flexibilities can influence the resulting fuel consumption to an extent which makes it worth considering the application of correction functions to compensate for deviations against the target values. Such correction functions have several benefits: + The repeatability increases + In test programs other than type approval tests, larger deviations against the target values may be typical. In such cases the application of the correction functions could help to make single tests better comparable and to increase the repeatability. + Making use of the flexibilities to reduce the CO2 test result gives a better type approval value but does not influence the real world CO2 emissions. Thus the test result should reflect reality better if the result is corrected for deviations against the target values of the test procedure. + The need to optimise the position of the test conditions within the range of flexibilities is reduced to a large extent. Making use of flexibilities ranges from driver training over calibration of test utilities up to optimising the alternator control unit to cycle conditions. Eliminating the need for optimisation of such parameters shall reduce the overall effort for testing without negative effect on real world CO2 emissions. - A negative impact is that the complexity of the test evaluation increases and additional signals need to be measured, such as current flow to and from the battery. The report investigates a series of corrections that could be applied to variations of test parameters within the tolerances ranges allowed by the WLTP GTR provisions. The corrections cover both the chassis dynamometer and coast down test procedure.

ELSS - Earth, Life and Social Sciences
Urban Mobility & Environment
Mobility
Reliable Mobility Systems
Traffic
STL - Sustainable Transport & Logistics

http://resolver.tudelft.nl/uuid:5a8b7a28-be6b-4fbe-ba03-8049e394b433

527548

TNO 2015 R10955

TNO, Delft

report