ESC-爆震控制课件

Electronic

Spark

Control

(ESC)Factors

Affecting

Knockcylinder

and

headdesignAgingcarbon

build-upcompression

ratioTemperatureHumidityOctaneAlcoholSupercharging

(turbo)Air-fuel

ratio

(altitude)EGRSpark

plug

heatrangebase

engine

designwear,

carbonbuild-uphot

spots

start

auto-ignitionhigher

CR

increases

knockinghigher

temperature

increases

knockinglower

humidity

increases

knockinghigher

octane

decreases

knockinghigher

alcohol

decreases

knockingincreases

knockingleaner

A/F

increases

knockingmay

cause

A/F

imbalance

between

cylindershotter

increases

knockingEngine

loadRPMTIPINhigher

load

increases

knockinglower

RPM

less

engine

noise

easier

to

hear

knockingAF

ratio

goes

lean.

Trade

off

with

emissions

and

driveabilityEquipment4-channel

oscilloscope

with

FFT checking

windows,

center

frequencyBNC

cable,

terminating

resistors

(100kΩ)listening

deviceelectrical

toolkitFlashlight

(torch)Inverterengine

and

chassis

dynoslow

and

high

octanefuelsdetermine

correct

detection

and

no

false

detection/retardco-axial

(shielded)

cable,

soldering

iron,

wire,terminals,check

pin

assignments

and

connectionsscope,

listening

device,

computer,

telephonesteady

state

work

in

a

stable

environmentcheck

windows

and

authority

(maximum

spark

retard)low-quality

low-octane

fuel

(pump

says

90#

but

actually

lower)hand-built

computer

and

data

collection

device

for

sensorlocation

study

(10

were

built

in

Kokomo)Knock

Analysis

Instrument

(KAI)Spare

sensors,

connectors,

terminalsSuction

cupsCopper

tubingExhaust

manifold

boltsstethoscopeto

put

DU

onto

dashto

hear

knocking

if

no

listening

deviceto

attach

copper

tubelistening

to

engine

noiseDefinitionsIn

explosive

detonation,

the

flame

speed

may

be

2,500

to

3,000

feet

persecond

(750-900

m/s)

as

opposed

to

200

to

300

ft/s

(60-90

m/s)

for

thenormalburning

rate.Octane:

resistance

to

explosive

combustion.

alcohol,

lead,

manganese,humidity

can

increase

octane.Key

AdvantagesMaximum

torque

controlEngine

runs

on

knockborder

lineFuel

variationProtects

engine

fromknock

due

to

bad

fuelOctane

selectAuto

selection

of

high

andlow

octane,

no

switch

inputnecessaryDigital

knock

controlProgrammable

filterCylinder

coordinated

knockIncreases

torque

on

smallenginesFuel

economy

and

emissions

also

affected

by

spark.From

MT20

presentation

by

Serge

LambermontMBT

SparkDeterminationFrom

the

GM

Automotive

Test

Code,

1994Flat

Response

Knock

Sensor

FamilyCourtesy

of

K.

Miura–

Self

generating

piezo-electric

sensor

with

flatfrequency

response

overrange

of

5-18

kHz–

Voltage

outputproportional

to

enginecombustion

intensityKnock

sensor

signalIRIC

filtered

signalIRIC

integratorADESCIntegrator

averageRaw

Mean

AverageDeviationFiltered

Mean

Average

DeviationKnock

ThresholdFast

AttackFast

RetardOctane

ScalerAdaptive

RetardSpark

advance

referenceIRICDetectionSpark

controlGainWindowcenter

frequencyIntegration

constantIntegration

constantMADFilter

coefficientMultiplier

calibrationsAttack

and

recoveryHigh/Low

octane

sparkESC

MainFunctionsVibration

Based

System

MechanizationPin

3

is

the

sensoroutputPin

4

is

theintegratorPin

6

is

thewindowFrom

the

IRIC

ApplicationFrom

IRIC

applicationIRICMicroprocessorFilter

andamplifierKnocksensorRawsignalSensorgroundESTorCAMintegratorwindowProcessed

sensor

signaloscilloscopeSPI

Integrateand

holdECMProcessedsensorsignalSensorgroundMDSDUPCInstrumentationM/T

Blazer

onperformance

dynoKnock

event

at5900RPMMAP

=

95

kPa(WOT)FFT

is

5.00

kHz

perdivision

(

=50

kHzfor

the

screen)+9º

spark(fromB2MT2203.cal)The

system

iseffective

atmaximum

RPM

andload.

Bycountingthe

signalpeaksdivided

by

thetimeelapsed

yields

afrequency

of6.7kHz.Conclusion:

Thisshows

that

thewindow

and

centerfrequency

are

setproperly.Blazer

Knocking

5900

RPM,

95

kPa

(WOT)Fast

Fourier

Transform

(FFT)very

high

peak

at

7

kHzKnock

eventFFTsignalintegratorwindowsparkKnock

sensor

signal

showing

11.5

kHz

onlySGM

2.0L

M/TW-car

with

newpistonsKnock

eventESTintegratorSensorsignalwingate11.5

kHzFFTESTAwindowSensorsignal(fromIRIC)integratorKnockeventLargeintegratorvalueNormalcombustionNormalcombustionDong

An

1.0L

engineFrom

Vibration-based

knock

detection

calprocedureCenter

FrequencyCaltools

Center

Frequency

CalibrationIRIC

/OptionsInit

gain,

Q,

CF,

int

constinitializationsWindowStart,

durationGAIN

controlUpper,

lower,

adjustment,maximumIntegratorADESCIntegrator

averageRawMADfiltered

MADthresholdCo-efficientKnock

presentIncreasing

TPS

RPMDecreasing

TPS

RPMSteady

state

TPS

RPMKnock+ΔRPM-ΔRPM+ΔTPS-ΔTPSMaxMinLoadcompensationMADmultiplierΔTPSTimer,

offsetPEcompensationΔRPMTimer,

offsetFilter

co-efficientFiltering

disableΔRPMΔTPSΔMAPTransient

timeFiltering

enableIRICECMThreshold

CalculationIntegratorAverage

=

IntegratorAverage

+

(ADESC

-

IntegratorAverage)

*

MultiplierUpdating

in

“ESC_Event”When

KnockPresentIntAveQ

*

K_IntegratorfiltermultiplierelseIntAveQUpdating

in

125msec

loopConstantKnockThreshold=IntegratorAverage+

noise_bandUpdating

in

“ESC_Event”noise_band

=

FilteredMAD

*

MADMultiplierUpdating

in

“ESC_Event”ConstantUpdating

in

15.6msec

loopFilteredMAD

=

FilteredMAD

+

(RawMAD

-

FilteredMAD)*K_MADFilterCoefficientRawMAD=

IntegratorAverage

-

ADESCUpdating

in

“ESC_Event”MT20

KNOCK

DETECTIONCourtesy

of

Hiroshi

UikeESCFastRetard

=

ESCFastRetard

+

ESCFastAttack*KnockLevelUpdating

in

“ESC_Event”KnockLevel

=

ADESC

-

KnockThresholdUpdating

in

“ESC_Event”ESCFastAttack

=

F_ESCFastAttack(RPM)Table

look

upUpdating

in

15.6msec

LoopUpdating

in

“ESC_Event”RPM

variable

is

updated

in

7.81msec

loopFAST

RETARD

CALCULATIONCourtesy

of

Hiroshi

UikeThreshold

Calculation

and

Knock

DecisionKnock

eventThresholdMultiplierFiltered

Mean

Averag