Measurement of noise from electrical
vehicles and internal combustion engine
vehicles under urban driving conditions
Oslo the12th of June
Lykke M. Iversen, Danish Road Directorate
Agenda
•
Background
•
Details of the measurements
•
The results
•
•
Steady speed
•
Engine braking
•
Acceleration
Conclusions
2.
Background
Litterature survey found that…
….. there is a potential for noise reduction by replacement of Internal
Combustion Engine (ICE) vehicles with Electric Vehicles (EV).
….. more knowledge is needed about the tires used on electric passenger
cars.
….. measurements of different driving situations should be carried out.
3.
Background
Noise from an average modern ICE passenger car
[km/h]
4.
Measurements
Citroën Berlingo EV
Citroën Berlingo ICE
Nissan Leaf EV
VW Golf Variant ICE
Michelin Agiglis 51
195/70 R15C
Michelin Energy
Saver
195/65 R15 G1
Michelin Energy
Saver
205/55 R16
Michelin Energy
Saver
205/55 R16
71 dB
69 dB
70 dB
70 dB
5.
Measurements
Temperature 16.6 °C.
Normalized to 20 °C
correction -0.05 dB/°C.
2-3 years old soft asphalt
6.
Measurements
Controlled pass by (CPB) was used to investigate the 3 different driving
pattern: Constant speed, engine braking and accelerating.
Centre of test lane
Microphone position
7.
Measurements
•
Constant speed:
•
•
Deceleration (Constant speed → Engine breaking):
•
•
10, 20, 30, 40, 50 and 60 km/h
20, 30, 40, 50 and 60 km/h
Acceleration:
•
10 → 30 km/h
•
10 → 50 km/h
•
20 → 40 km/h
•
20 → 60 km/h
•
30 → 50 km/h
•
40 → 60 km/h
8.
Results
The Berlingos noise levels at constant speed
EV
ICE
9.
Results
The Berlingos frequency spectra at constant speed
70
CPB noise level [dBA]
60
50
40
Berlingo ICE 9 km/h
30
Berlingo ICE 61 km/h
Berlingo EV 10 km/h
20
Berlingo EV 59 km/h
10
0
Frequency [Hz]
10.
Results
The Nissan Leaf and VW Golf Variant noise levels at constant speed
11.
Results
The Nissan Leaf and VW Golf Variant frequency spectra at constant
speed
12.
Results
CPB noise level [dBA]
The Berlingos noise levels at deceleration by75
engine braking
Constant speed
70
65
60
55
50
45
0
13.
10
20
30 40 50
speed [km/h]
60
70
Results
The Berlingos frequency spectra at deceleration by engine braking
70
CPB noise level [dBA]
60
50
40
Berlingo ICE 14 km/h
Berlingo ICE 61 km/h
30
Berlingo EV 13 km/h
Berlingo EV 57 km/h
20
10
0
Frequency [Hz]
14.
Results
CPB noise level [dBA]
The Nissan Leaf and VW Golf Variant noise levels at deceleration by
engine braking
75
75
CPB noise level [dBA]
70
65
70
65
60
55
50
45
Constant speed
0
60
Leaf
Golf
55
Poly. (Leaf)
50
Poly. (Golf)
45
0
10
20
30
40
50
60
70
speed [km/h]
15.
10
20
30
40
50
speed [km/h]
60
70
Results
The Nissan Leaf and VW Golf Variant frequency spectra at deceleration
by engine braking
16.
Results
The Berlingos noise levels at acceleration of various degree
ICE
17.
Results
The Nissan Leaf and VW Golf Variant noise levels at acceleration of
various degree
18.
Results
6,0
4,0
3,0
2,0
1,0
0,0
19.
Reduction [dB]
5,0
Conclusions
Constant speed
•
EVs are 4-5 dB less noisy than similar ICEs at low speed.
•
At about 30 km/h the difference in emitted noise is not significant.
Deceleration by engine braking
•
EVs are 2-4 dB less noisy than ICEs at low speed.
•
At higher speed the difference decrease as the tire/road noise is getting
dominant.
Overall conclusion
EVs will have the potential to reduce the traffic noise in carparks and on
streets where vehicles travel with speeds under 30 km/h.
20.
Thank you for your attention !!!
Compett.org