1. Emissions testing with PEMS and random driving cycles – First preliminary results
RDE-LDV working group
13 April 2012
Pierre Bonnel
Martin Weiss
DG - Joint Research Centre (JRC)
IET - Institute for Energy and Transport

2. Introduction Objectives:
Assessing the functionality of the random cycle generator
Assessing the drivability of the random cycles
Comparing emissions: on-road driving and random driving cycles

3. Constructing cycles Data base of 20,000 short trips
Input: vehicle and dynamometer parameters; number of short trips, cycle duration and distance
Automatic establishment of the vehicle limitation curve
Random selection of short trips
Eliminating idling during the high-speed phase; including idling between short trips
Defining gear shift points

4. Constructing cycles Speed phases Vehicle limitation curve
Max. acceleration in ms-2
Cut-off speed, high-speed phase
Idling: beginning/end/ short-trips/phases/
Steven cycle soft
three phases ~ 300s each
Steven cycle medium
Steven cycle severe
three phases ~ 300s each
Random cycle 1 (rep.)
3-3-2 short trips
85%
3.6
60-100km/h
10/5-30/10s
Random cycle 2 (rep.)
0-60km/h
10/5-10/30s
Random cycle 3 (rep.)
1-1-3 short trips
100%
8.0
Random cycle 4 (rep.)
1-1-4 short trips
40-100km/h
5/20/5s
Random cycle 5
6-1-1 short trips

5. Constructing cycles

6. Drivability
Test vehicle: Euro 5 diesel, 4 cylinder, 55 kW, 105 g CO2/km
WLTC gear shift prescription; no pretesting of cycles
Deviation actual-scheduled speed [km/h]

7. Absolute speed deviation in km/h
Drivability
Absolute speed deviation in km/h
>2
>3
>4
>5
>6
>7
>8
>9
>10
Steven cycle: soft 8s 2s 0s
Steven cycle: medium
10s 5s
Steven cycle: severe
32s
11s 7s 6s 4s
Random cycle 1 9s 1s
Random cycle 1_rep
Random cycle 2
Random cycle 2_rep
Random cycle 3
Random cycle 3_rep
Random cycle 4
Random cycle 4_rep
Random cycle 5

8. Absolute speed deviation in km/h
Drivability
Comparison: drivability of previously designed random cycles
Absolute speed deviation in km/h
>2
>3
>4
>5
>6
>7
>8
>9
>10
Cycle 1
35s
13s 8s 2s 0s
Cycle 2
34s
12s 7s 3s 1s
Cycle 5
32s
11s
Cycle 6
20s
Cycle 7 9s 5s
Cycle 8
30s
Cycle 9
14s 6s 4s
Cycle 10
31s
NEDC/WLTP criteria: zero speed violations >2km/h.

9. Emissions results
Preconditioning before all random cycle tests (3 EUDC)

10. Emissions results
Average emissions (test averages and averaging windows)

11. Thank you! DG - Joint Research Centre (JRC)
IES - Institute for Energy and Transport
Pierre Bonnel
Martin Weiss