Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel … · Combustion Sensor for Diesel...

Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel Engines

Gérard TROY, Siemens VDOAlain RAMOND, Siemens VDOSandro GORETTI, Federal Mogul

Combustion sensingNOx (g/km)0.0 0.1 0.2 0.3

PM (g

/km

)

0.00

0.02

0.04

0.06

Japan 2005Japan 2005

LEV (CARB LEV I)

EURO IV

Tier 2, Bin 5Tier 2, Bin 5Euro VEuro V

New emission legislations for Diesel engines

HCCI with CLCCNeed of a pressure sensor

Pressure sensor portfolio

GPCSGlow Plug Combustion sensor

GPPSGlow Plug Pressure sensor

NICSNon intrusive Combustion sensor

Sensing principle :

Measurement of the deformation of the probeAdvantages :

- Direct pressure sensor ( Can be calibrated )- Robustness

Sensing principle :

Measurement of the deformation of the cylinder headAdvantages :- Low cost- RobustnessDrawbacks :- Need a calibration on engine

SAPS Stand alone Pressure sensor

Sensing principle :

Same configuration than GPPS but without the probe

Combustion sensing family( Cylinder head deflection measurement )

Pressure sensing family( Direct pressure measurement )

Sensing principle :

Same as GPCS

Advantages / Drawbacks:

- Do not require a hole in the cylinder

Combustion sensor : Measurement of cylinder head deflection versus direct measurement

GPCS: sensitive to

cylinder head deflection

GPPS: sensitive to glow plug

deflection only

Pressure sensor portfolio


Passive


Active

Calibration error

Ageing

sensitivity variations

hysteresis

error ( HF noise )

300%

0%1%2%3%4%5%6%7%8% P

rice

Acc

urac

y ( +

/-)

100%

200%

GPCS GPPS

Combustion sensing family


NICSNon intrusive Combustion sensor

Sensing principle :

Measurement of the deformation of the cylinder headAdvantages :- Low cost- RobustnessDrawbacks :- Need a calibration on engine

Sensing principle :

Same as GPCS

Advantages / Drawbacks:

- Do not require a hole in the cylinder

ShellElectrode Interface“Spring Zone”

Ceramic TubeSensor Electrodes

Piezo

Passive sensor:• signal conditioning in ECU

GPCS : Sensing principle

Piezo ceramic based product

Manufacturing process similar to knock sensor processRobust and environmentally sealedVery long time stability, (very low ageing rate of the piezo ceramic)High signal to noise ratio : Low sensitivity of the sensor to engine vibrations

GPCS : Accuracy

Signal to noise ratio

SNR always below +/- 1 bar

Hysteresis

050

100150200250300350400

0 0.5 1Pressure on piezo (MPa)

Ele

ctric

al c

harg

e (p

C)

2% hysteresis, repeatable, can be compensated in ECU

GPCS : Sensitivity change

94%

95%

96%

97%

98%

99%

100%

101%

0 20 40 60 80 100 120 140 160Load (Nm)

Rel

ativ

e se

nsiti

vity

RPM 2000

RPM 3000

RPM 4000

Change of sensitivity over temperature: 5%

- Very repeatable

- Easily compensable in open loop

Change of sensitivity over Engine conditions

(Load / rpm): < +/- 2%

-1%

0%

1%

2%

3%

4%

5%

40 50 60 70 80 90 100

Water coolant temperature (°C)

Sens

itivi

ty c

hang

e

GPCS Sensor Error summary

0123456789

10

0 50 100 150 200Pressure (bar )

erro

r (ba

r) HF noiseHysteresisSensitivity

variationsAgeing

+/- 4 % accuracy

GPCS accuracy is 4% without calibrationGPCS robustness demonstrated on engine testsGPCS SNR evaluated successfully for accurate measurement

of MFB ( location of the 50% of the heat release curve ), thus enabling HCCI control

GPCS as used for HCCI control:Sensor signal is used to compute MFB_50% angleECU is handling following operation:

charge to voltage conversionconstant amplification (no open loop compensation)low pass 5Khz filteringsignal pegging (offset compensation) @ constant crank angle

2 different engines have been used for tests:

GPCS within engine control strategy

Ref sensor

Raw GPCS signal

Filtered GPCS signal

MFB_50% computation

cte offset

Pressure sensing family


Sensing principle :

Measurement of the deformation of the probeAdvantages :

- Direct pressure sensor ( Can be calibrated )- Robustness

SAPS Stand alone Pressure sensor

Sensing principle :

Same configuration than GPPS but without the probe

Probe stress measurement

Active sensor calibrated

Conditioning in the sensor

Standard analog output

GPPS : Sensing principle

Use of piezo-electric elementMiniaturization of the sensor in the bottom

of the Glow Plug shell ( M8 )Use of a ceramic heating probeAssembly of the ceramic probe on a "Thick

membrane "Solution fully sealed, not sensitive to dust

contaminationElectronic integrated into the Glow Plug shellCompact integrated connector within automotive

standards

GPPS : The piezo electric element

-10

-50

5

10

1520

25

30

-1.5 -1 -0.5 0 0.5

applied stress (MPa)

Cha

rge

Den

sity

(pC

/mm

2)

0

5

10

15

20

25

0 200 400 600 800 1000 1200Preload on the piezo ( N )

Piez

o se

nsiti

vity

( pC

/N )

Highly stable poly crystalline piezo electric element

Lead free compositionHigh Curie temperature : 650°CNo hysteresis ( < 0.1 % )Low sensitivityTime stability demonstrated in other product

application with 500 °C operating temperatureNo change of sensitivity versus preload and

temperature ( < 1% )

GPPS : The ceramic probe technology

Ceramic Technology for the "Glowing Part" has been developed byFederal Mogul in order to fulfil new Customer's requirements.

The Federal-Mogul Ceramic Glow Plug Technology is a multi-layer structure made of a silicon nitride substrate with different percentage of Molybdenum Di-Silicide to create conductive paths

The heating part is the tip of the ceramic probe, where the major amount of electrical resistance is concentrated

The technology is fully protected by several worldwide patents

Ceramic heating element are proposed by Federal Mogul for standard plugs, and for GPCS, though GPPS will be available withCeramic probe only

1.08 1.09 1.1 1.11 1.12 1.13-10

0

10

20

30

40

50

60

70

80

time (s)

bar

3000 RPM / 80 Nm

GPPS : Example of engine test results

1.15 1.155 1.16 1.165 1.17 1.175 1.18 1.185 1.19 1.195 1.2

0

20

40

60

80

100

120

time (s)

bar


3000 RPM / 120 Nm


1.02 1.03 1.04 1.05

0

20

40

60

80

100

time (s)

bar

1.03 1.04 1.05

-5

0

5

time (s)

erro

r (b

ar)

GPPS High frequency noise below +/- 0.5 % of FSO

-50 0 50 100 150-50

0

50

100

150

reference sensor (bar)

GP

PS

(ba

r)

GPPS Hysteresis below 0.5 %

GPPS : Hysteresis

-5-4-3-2-1012345

Idle

2000

rpm / 2

0 Nm

2000

rpm / 8

0 Nm

2000

rpm / 1

20 N

m30

00 rp

m / 20 N

m30

00 rp

m / 80 N

m

3000

rpm / 1

20 N

m40

00 rp

m / 20 N

m40

00 rp

m / 80 N

m

Sens

itivi

ty v

aria

tion

( %

Sensitivity variations always below 1%

GPPS : Sensitivity changes versus engine conditions

GPPS : Sensor Error summary

Target of GPPS : 3.5 % Accuracy over lifetimeIncluding calibrationSensor time stability will be soon demonstrated by engine endurance tests

0123456789

10

0 50 100 150 200Pressure (bar )

erro

r (ba

r)

HF noiseHysteresis / Thermal choc errorSensitivity variations

Ageing

+/- 3.5 % accuracy

Calibration error

GPPS : Heat release monitoring

Thank you for your attention !

Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel … · Combustion Sensor for Diesel...

Documents

Transcript of Glow Plug Integrated Piezo-Ceramic Combustion Sensor for Diesel … · Combustion Sensor for Diesel...