1. CLEAR Graz 19.02.2013 Stefan Hausberger, Nikolaus Furian
Classification of Emissions from Automobiles in Real Driving
Graz
Stefan Hausberger, Nikolaus Furian

2. „Risk for legislation“
Introduction
Goal for evaluation method:
An evaluation method for PEMS tests at passenger cars shall
ensure low RDE by good coverage of real driving situations (important for legislation and for meeting air quality targets)
enable a fair comparison of measured emissions also for very different driver behaviour (important for industry)
PEMS results for mid class EURO 6 car: driving style correlated variability
Moderate driving
Normal driving
Aggressive driving
„Risk for legislation“
„Risk for OEM“
HDV: g/kWh
LDV: g/km!
Low kWh/km “average” kWh/km high kWh/km
Introduction
Interface
Frequency map
Data and settings
Output

3. Weighting emission data using a target frequency map
Average of emission data over e.g. 3 seconds is computed
Resulting average values are assigned, according to engine speed and engine, to an array with the same structure as the target frequency map,
Method
Interface
Frequency map
Data and settings
Output

4. Weighting emission data using a target frequency map
Average values of the cells in the array are built and weighted with the corresponding frequencies of the target
Engine Speed
Power
Weighted Emission=
⋅0.2+
⋅0.14+…+
⋅0.02
Emission Per Distance:
Weighted Emission g km = Weighted Emission g h Weighted Speed km h
Mean Emission g km = MeanEmission g h Mean Speed km h
Method
Interface
Frequency map
Data and settings
Output

5. REDES User Interface Method Interface Frequency map Data and settings
Output

6. Loading target frequency maps (Goal Patterns)
Absolute from file:
De-normalize from standard map:
Standard map may be configurated via XML- settings file
<PPattern>
<P>-1.8</P>
<P>-1.2</P>
<P>-0.6</P> …
Method
Interface
Frequency map
Data and settings
Output

7. Loading data and calculation Settings
Input Data:
Settings:
Averaging width and boundaries can be set by the user
Emission values to be loaded are optional and may be configurated via XML- setting file
Method
Interface
Frequency map
Data and settings
Output

8. Goal Pattern Analysis Goal Pattern vs. Driving Pattern File Selection
Statistical Analysis
Method
Interface
Frequency map
Data and settings
Output

9. Thank you for your attention!

10. Normalization and/or categorisation of target frequency maps
Possible Methods
Different “Target Frequency maps“ for different classes of passenger cars (would require a framework to classify passenger cars)
Introduction of a normalized power on the X-axis of the target frequency maps
Unified and normalized target frequency map would be easier to handle. However, the existence of a fair normalization has to be proven.
In the following a promising method is presented:
Content
Introduction
Method
Optimisation
Sources
Application
transport time
Outlook

11. Normalization of target frequency maps
𝑃𝑛𝑜𝑟𝑚= 𝑃𝑒𝑚𝑜𝑡 𝑃𝑤
with PW…….power at wheels (v * F) from settings at vehicle type approval at defined velocity and acceleration (e.g. 70 km/h with 0.45 m/s²),
𝑃 𝑤 =𝑣⋅(𝐴+𝐵⋅𝑣+𝐶⋅ 𝑣 2 +𝑆𝑀𝐾⋅𝑎)
Small car
TUG-Data
SMK: 1130kg kg
A: 110,9
110.90
118.40 N
B: 0,409
0.41
N h/km
C: 0,02938
0.03
N h²/km²
Straßenlast für Normierung v=
70.00
km/h
a =
0.45
m/s²
--> Pe =
15.40 kW
Example for normalized map
Application for considered vehicle:
De-normalise x-, y-axis from frequency distribution to rpm and kW based on chassis dyno type approval settings
Normalisation considers influence of different vehicle specifications
Easy to handle
P_norm Pe
from to
Frequency
8.20
126 0%
7.30
112
6.40 99
5.50 85
4.60 71 1%
3.70 57 2%
2.80 43 6%
1.90 29
11%
1.00 15
38%
0.10
1.54
15.40
12%
-0.10
-1.54
10%
-1.00
-15.40
20%
Ok if “normalized frequency distributions” do not differ over vehicle classes!
Content
Introduction
Method
Optimisation
Sources
Application
transport time
Outlook

12. Normalization of target frequency maps
Analysis of BMW Data: Mini, 320d and X5
Comparison X-axis in kW (left chart) and normalized axis (right chart)
Over absolute power the X5 has, as expected, higher frequencies for higher levels of power than the 320d or Mini
A normalized power leads to similar histograms (right chart)
Particular attention only on high levels of power
Further tests suggested!
Content
Introduction
Method
Optimisation
Sources
Application
transport time
Outlook