PEMS data evaluation: binning - Europa · Sum of all (NO x) emissions within a bin Sum of CO 2 or distance within a bin Results per bin calculated (weighted average) HD: first 10

PEMS data evaluation: binning

Audio/web meeting - February 19, 2013

Henk Dekker, Robin Vermeulen

Contents

Binning method

CO2 specific data evaluation

Excel tool

Extra Slides

February 19, 2013Henk Dekker, Robin VermeulenPEMS data evaluation: binning

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Binning method as used by TNO

Pre-processing of PEMS data with EMROAD

(data checking and time-alignment)

All measurements used

5 km/h bins (wider bins are possible, eg. city/rural/highway)

Sum of all (NOx) emissions within a bin

Sum of CO2 or distance within a bin

Results per bin calculated (weighted average)

HD: first 10 minutes not evaluated (engine coolant > 70°C)


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Binning method as used by TNO

Limits per bin or per type of operation possible

All operating conditions weighted equal

Insensitive to trip selection

Screening of vehicles with on-board sensors is possible (SEMS)


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Binning: emission expressed in g/km (single bins)

CO2 specific NOx emissions binned in: small bins (5 km/h) and inlarge bins (0-50, 50-75, >75km/h)


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Contents

Binning method


Excel tool


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less sensitive to measurement errors

less sensitive to trip composition and altitude changes

better results during idling and very low and high load operation

no vehicle signals or data communication needed

hybrids can be measured and evaluated

can be related to the EL via CO2 emissions in TA test cycle

which CO2 emissions? Vehicle specific or fleet average or ?


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Contents

Binning method


Excel tool


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Excel tool


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Excel tool


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Excel tool


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Extra Slides


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0

25

50

75

100

125

150

175

200

225

250

0

2

4

6

8

10

12

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0 20 40 60 80 100 120 140

Co

un

t

NO

x/C

O2

[g/k

g]

Average vehicle speed [km/h]

CADC 1MPV Euro 5a diesel, 1580 kg

NOx/CO2 [g/kg] Count


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How does it work? The example of CO2 specific NOx emission

The NOx and CO2 mass emissions are measured from the tail pipe,

for instance with PEMS.

For every defined speed interval the mass emissions of CO2 and NOx

are summed up after which the ratio of both values is calculated:

This results in a ‘profile’ of the CO2 specific emission over the speed

range of a vehicle.

[ ]

[ ]∑

∑+=

=

+=

== 5

2

5

2

/

/ viv

viv

viv

vivx

x

skgCO

sgNOkgCOpergNO


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Calculation example PEMS binning method

Data points within a bin (NOx, CO2): (1, 10), (0.1, 0.01)

(in reality much more data points are used)

Sum of all NOx emissions / total CO2 emissions (weighted average)

(1+0.1) / (10+0.01) = 0.11

And NOT:

Mathematical average of specific emissions

(0.1+10) / 2 = 5.05


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See also the documents on CIRCABC:

Direct links (when logged in):

https://circabc.europa.eu/sd/d/02ed6a91-0d2d-4c68-8214-

133b98bf5d33/TNO_RDE_presentation.pdf

https://circabc.europa.eu/sd/d/1c534ccd-7abe-45ea-ba26-

12564413d5cb/Simplified%20emission%20checking.pdf

https://circabc.europa.eu/sd/d/3f003a9e-7912-41b0-aa1e-

6d2bf13a3d9f/TNO_RDE-PEMS%20testing%202011.pdf


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See also the documents on CIRCABC:

If the links do not work, the documents can also be found under:

CIRCABC>Enterprise>New light duty test procedures: WLTP, MAC,

...>Library>meetings>120301_rde_ldv >Presentation TNO (data

variability and analysis)


...>Library>meetings>120911_-_rde-ldv>TNO SEMS Simplified

emission checking presentation


...>Library>meetings>Pre-2012 meetings>111020_-_rde-ldv>TNO

LDV-PEMS test results 2011


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Documents

PEMS data evaluation: binning - Europa · Sum of all (NO x) emissions within a bin Sum of CO 2 or distance within a bin Results per bin calculated (weighted average) HD: first 10