1. WLTP-08-19e
BMW,
Christoph Lueginger
WLTP Road Load Family
Proposal on a family definition for road load determination

2. WLTP Road load family Introduction Agenda:
Validation testing, current status and program.
Current proposal.
Minutes of Geneva-meeting 06/2014:
WLTP Road Load Family, BMW,

3. measurement program - road load family validation
WLTP road load family validation tests
measurement program - road load family validation
320i ed - AT RR
Aero
mass
320d - AT RR
Aero
mass
328i - AT RR
Aero
mass
435i- AT RR
Aero
mass
1.3 MJ
1.3 MJ
1.4 MJ
The difference between the vehicles is a first guess and will be determined precisely by component measurements (weight, aerodynamics, RR).
The measurements of the first two vehicles is in progress, finalization is planned for end of 2014, if the weather in Munich allows coast down testing, otherwise mid of 2015.
WLTP Road Load Family, BMW,

4. from WLTP-DTP-LabProcICE-172 - Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family
road load family definition proposal
Starting from the CO2 family and dropping the engine related issues, the following definition results.
Proposal for definition of a "road load family":
Vehicles identical with respect to the following characteristics shall be considered to be part of the same road load family:
(a) Transmission type (e.g. manual, automatic, CVT) and transmission model (e.g. torque rating, number of gears, number of clutches, etc.);
(b) n/v ratios (engine rotational speed divided by vehicle speed). This requirement shall be considered fulfilled if, for all transmission ratios concerned, the difference with respect to the transmission ratios of the most commonly installed transmission type is within: [25] per cent;  can be much bigger than for the CO2-family, influence very small, criteria could even be deleted!?
(c) Number of powered axles;
(d) [RESERVED: family criteria for EVs].  Out of the EV criteria there might be also criteria to be taken into account for the road load family, especially if the electric machine is not decoupled!
The range between the vehicle with the lowest energy demand over a full WLTC class 3 and the vehicle with the highest energy demand shall not exceed [5] MJ.
from WLTP-DTP-LabProcICE Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family, BMW,

5. WLTP Road Load Family next steps Results of validation measurements.
Is there input or feedback from other participants?
Please give your feedback on first draft provided.
Members of TF:
Contact Persons: Rob Cuelenaere (TNO), Christoph Lueginger (BMW)
Experts: Markus Bergmann (Audi), Norbert Ligterink (TNO), Toshihisa Yamaguchi (Japan), Annette Feucht (Audi), Nakhawa (India), Iddo Riemersma (T&E), Bill Coleman (VW), Caro Hosier (Ford), Laura Bigi (PSA), Bob Latu (Renault), Bertrand Mercier (PSA), Helge Schmidt (TÜV Nord), André Rijnders (RDW), Klaus Steininger, (EU Com), Beatrice Lopez (UTAC), Folko Rohde (VW), Kai Behlau (VW)
WLTP Road Load Family, BMW,

6. from WLTP-DTP-LabProcICE-172 - Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family
Backup
Backup
from WLTP-DTP-LabProcICE Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family, BMW,

7. from WLTP-DTP-LabProcICE-172 - Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family
Status and Introduction
In the current GTR two coast downs are necessary for one CO2-family.
Coast down testing is very time consuming and inflexible (weather, track capacity, …)
Many parameters that must be equal within one CO2-family (for good reasons) have no other effect on the road load except for their effect on weight and aerodynamics which is accounted for in the interpolation.
Example: The engine is decoupled during coast down, therefore neither the engine type nor the engine temperature is relevant for road load determination.
A definition of a road load family, that is bigger than the CO2-family, is possible.
A road load family avoids unnecessary workload without losing accuracy.
Such a family has synergistic effects e.g. a family for the alternative warm-up procedure could also be this road load family.
If the concept of developing a road load family is agreed, the details should be worked out in a small subgroup.
from WLTP-DTP-LabProcICE Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family Concept, BMW,

8. from WLTP-DTP-LabProcICE-172 - Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family
Clarification of road load influences
influences on road load
assessed by
mass
combined approach
rolling resistance
aerodynamics
drivetrain type (2WD/4WD)
tbd in
road load family
drivetrain losses
gearbox type (MT, AT, …)
tbd
not relevant
for road load
The engine has no influence on road load, as it is decoupled, apart from:
Weight, aerodynamic (and rolling resistance) influences.  They are covered by the calculation of the individual road load coefficients!
from WLTP-DTP-LabProcICE Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family Concept, BMW,

9. from WLTP-DTP-LabProcICE-172 - Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family
Calculation of road load influences, Annex 7
Calculation of road load for individual vehicles in the CO2 vehicle family
Calculation of cycle energy per phase
Calculation of the CO2 value for an individual vehicle by the CO2 interpolation method
Formulas for road load family
Formulas for both families
Formulas for CO2-family
from WLTP-DTP-LabProcICE Comparison RLD flatbelt_VW.pdf
WLTP Road Load Family Concept, BMW,

10. WLTP – Family Definitions
Example With limited parameters
RLD: Road Load Determination ATCT: Ambient Temperature Correction Test CA: Combined Approach
1. RLD – Family 3 series MT Gasoline / Diesel
2. RLD – Family 3 series AT Gasoline / Diesel
CA Family 3 series MT Gasoline
CA Family 3 series MT Diesel
CA Family 3 series AT Diesel
CA Family 3 series AT Gasoline
2. ATCT Family, Gasoline MT / AT
1. ATCT Family, Diesel MT / AT
2. ATCT Family, Gasoline MT / AT
3. RLD – Family 5 series MT Gasoline / Diesel
4. RLD – Family 5 series AT Gasoline / Diesel
CA Family 5 series MT Gasoline
CA Family 5 series MT Diesel
CA Family 5 series AT Diesel
CA Family 5 series AT Gasoline