test based optimization of nvh for hybrid and electric … based optimization of nvh for hybrid and...

Test based Optimization of

NVH for hybrid and electric

vehiclesGert Sablon, Director Business Development, STS TEST

Realize innovation.Unrestricted © Siemens AG 2017

Unrestricted © Siemens AG 2017

Siemens PLM Software

Optimizing NVH performance when fuel economy rules the world

Main drivers in Powertrain Development

Increase fuel efficiency Reduce emissionsReduce NOX, CO2

BUT keep performanceHP, Torque, Driving Pleasure,…



Main drivers in Powertrain Development…

…Resulting in technology and innovation boost

Use of smart electronics & controls Complete new powertrains

Adapt fuel injection method / timing

Cylinder de-activation

Complex CVT transmission

…

Fully electric

Hybrid

Fuel cells

…



Main drivers in Powertrain Development…

…Leading to new challenges for the NVH engineer

How to handle new noise

sources?How to keep control on NVH?

Avoid reduced NVH while improving

performance and fuel efficiency?

Electric motor noise

Battery cooling noise

Power electronics noise

…

While keeping/increasing

development efficiency?

How to reduce development time?

How to design-right-first time?



From Combustion engine towards electric drive

So what is the difference?

2600.000.00 Hz

mic (CH1)

3500.00

900.00

rpm

Tacho1 (

T1)

80.00

-20.00

dB

(A)

Pa

AutoPower mic (A) WF 126 [981.36-3466.8 rpm]

Motor order

ICE driven Electric driven (more high frequency content)

Resonance

Motor orderResonance

Off-zero harmonics. Origin?

Is the Sound Quality better for EV?



Ancill. Noise EM/TM

Wind Noise

Inverter

Hybrid - Electrical Vehicle

Frequency ranges of interest

[Km/h]

[Hz]200 1000 8000

[Km/h]

[Hz]200

Engine – Structure B.

1000 8000

Road Noise – Tire Noise

Wind Noise

2000


Engine – Air B.

60

100

40

100

2000

400

400

ICE

EV



Shift in NVH development for electric vehicles



Ancill. Noise EM/TM

Wind Noise

Inverter



[Km/h]

[Hz]200 1000 8000

[Km/h]

[Hz]200


1000 8000


Wind Noise

2000


Engine – Air B.

60

100

40

100

2000

400

400

ICE

EV



But even new ICE are impacting NVH testing

How 4 separate measurement systems have become one system

Acquisition System 1

NVH Analysis


Torsional Vibration Analysis


Online Angle Domain /

Combustion Analysis


ECU Communication

CCP / XCP

How 4 separate systems

have become 1 system for

the NVH engineer



Balancing the NVH against other performance parameters

Past Present

RPM

To

rqu

e

Engine Map = Noise in function of RPM and Torque

No

ise

Performance

Torsion



Ancill. Noise EM/TM

Wind Noise

Inverter



[Km/h]

[Hz]200 1000 8000

[Km/h]

[Hz]200


1000 8000


Wind Noise

2000


Engine – Air B.

60

100

40

100

2000

400

400

ICE

EV



Full support for the Sound Quality Engineering

Noise Signature Design of Electric Powertrain

Operation Condition Test

Field validation with SCADAS XS &

LMS 3D binaural headset

Problem identification

Sound Diagnosis

Inverter control optimization

Sound QualityAnalysis &

Metrics



Noise Signature Design of Electric Powertrain

Measured Sound

~8000Hz Strong tonal component

~4000Hz Large number of closely spaced

tonal with the same amplitude =>

Modulation

Sound recording & field validation Sound analysis & features identification

Sound Design: AMESim for control strategy modification + Sound Quality metrics for validation

Strategy 1: get rid of the tonal

components with a random control

Strategy 2: Shift up in frequency the tonal

components, to less audible frequencies

Prominence ratio

Loudness

Sharpness

Prominence ratio

Loudness

Sharpness

Still sounds annoying Target sound



Complexity of Hybrid powertrains

Multiple rotating shafts



Gear whine becomes much more apparent

Source of gear whine comes internal excitation within

the gearbox (e.g. stiffness variations, geometric

excitation, … ) = microscopic phenomena at the level of

teeth design and teeth accuracy

Effects of modifications to the gearbox can be analyzed

on test benches with SCM-RV4 module and incremental

encoders (transmission error measurement)

Gear transmission error test rig in Leuven



Ancill. Noise EM/TM

Wind Noise

Inverter



[Km/h]

[Hz]200 1000 8000

[Km/h]

[Hz]200


1000 8000


Wind Noise

2000


Engine – Air B.

60

100

40

100

2000

400

400

ICE

EV



Road noise Reduction

TPA

Challenge/objectives

• Reduce road noise in passenger compartment

• Find smart and effective solutions that do not reduce

handling performance or add too much weight or cost

Solution

• Support of all techniques for force identification

• Use of strain AND acceleration for road noise TPA

Benefits

• Gain insight into vehicle road noise behavior via the

source-transfer-receiver methodology

• Allow separation of airborne and structure-borne

contributions as well as detailed front and rear

axle/suspension contributions

• Map improvement potential by verifying modifications



More requirement for Transient TPA

Addressing root cause analysis of drivability

…Transfer Path Analysis (TPA)

Insights in contribution

to NVH Comfort

…in “full NVH Context”

To link transient loads

to Dynamic Interface Forces…

Transient Load identification

Strain gage technology

Low frequency

Tip-inStrain responses (right) during Tip-in

Typical Tip-in / Tip-out

ResponseTransient torque

oscillations in the driveline

Amplified by P/T,

suspension and body

modes

Resulting seat and

steering-wheel vibrations

Time-domain Transfer Path Analysis for Transient Phenomena Applied to Tip-in/Tip-out (Shock & Jerk)

H. Shiozaki, Y.Iwanaga, MMC, T. Geluk ,F. Daenen, J, Van Herbruggen, LMS, SAE 2012-01-1545



Ancill. Noise EM/TM

Wind Noise

Inverter



[Km/h]

[Hz]200 1000 8000

[Km/h]

[Hz]200


1000 8000


Wind Noise

2000


Engine – Air B.

60

100

40

100

2000

400

400

ICE

EV



Aero-Acoustic TestingTrend to capture as much as possible during expensive wind tunnel tests



Aero-Acoustic TestingIntegrated solution for aero-acoustic testing - Combine different technologies



Aero-Acoustic TestingValue of fully integrated solution

Where does an external source leak into the

vehicle?

Large Array from Daimler AG presentation by Ralph Buckisch, 10th

FKFSconference, September 2015

Overall 3DCam results

Top Array Result

3DCam results related to source

selected outside



Ancill. Noise EM/TM

Wind Noise

Inverter



[Km/h]

[Hz]200 1000 8000

[Km/h]

[Hz]200


1000 8000


Wind Noise

2000


Engine – Air B.

60

100

40

100

2000

400

400

ICE

EV



From NVH point of view, HVAC systems are very complex

Multiple potential noise & vibration sources

Compressor, Condenser, Tubing, HVAC module with blower & motor, Ducts & vents

Multiple potential transfer paths & mechanisms



Validating modifications to battery cooling unit design without

need for full vehicle validation

UNIT LEVELVEHICLE LEVEL

Modification at unit

projected to in-vehicle

SOURCE

Inlet & Outlet Ducts

located in cabin interior

Transfer

between sources and

cabin microphones

RECEIVER

Cabin Sound Pressure

Level

test based optimization of nvh for hybrid and electric … based optimization of nvh for hybrid and...

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