SE1650887A1 - Method and system for controlling fuel injection in connection to engine start procedure - Google Patents

Method and system for controlling fuel injection in connection to engine start procedure Download PDF

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Publication number
SE1650887A1
SE1650887A1 SE1650887A SE1650887A SE1650887A1 SE 1650887 A1 SE1650887 A1 SE 1650887A1 SE 1650887 A SE1650887 A SE 1650887A SE 1650887 A SE1650887 A SE 1650887A SE 1650887 A1 SE1650887 A1 SE 1650887A1
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SE
Sweden
Prior art keywords
engine
fuel
amount
power demand
speed
Prior art date
Application number
SE1650887A
Other languages
Swedish (sv)
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SE541113C2 (en
Inventor
Jacobsson Susanna
Nordin Mikael
Original Assignee
Scania Cv Ab
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Publication date
Application filed by Scania Cv Ab filed Critical Scania Cv Ab
Priority to SE1650887A priority Critical patent/SE541113C2/en
Priority to DE102017005860.1A priority patent/DE102017005860A1/en
Publication of SE1650887A1 publication Critical patent/SE1650887A1/en
Publication of SE541113C2 publication Critical patent/SE541113C2/en

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/04—Introducing corrections for particular operating conditions
    • F02D41/06—Introducing corrections for particular operating conditions for engine starting or warming up
    • F02D41/062—Introducing corrections for particular operating conditions for engine starting or warming up for starting
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/04—Introducing corrections for particular operating conditions
    • F02D41/06—Introducing corrections for particular operating conditions for engine starting or warming up
    • F02D41/062—Introducing corrections for particular operating conditions for engine starting or warming up for starting
    • F02D41/064—Introducing corrections for particular operating conditions for engine starting or warming up for starting at cold start
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/14—Introducing closed-loop corrections
    • F02D41/16—Introducing closed-loop corrections for idling
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/30—Controlling fuel injection
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2200/00—Input parameters for engine control
    • F02D2200/02—Input parameters for engine control the parameters being related to the engine
    • F02D2200/021—Engine temperature
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2200/00—Input parameters for engine control
    • F02D2200/02—Input parameters for engine control the parameters being related to the engine
    • F02D2200/06—Fuel or fuel supply system parameters
    • F02D2200/0614—Actual fuel mass or fuel injection amount
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2200/00—Input parameters for engine control
    • F02D2200/02—Input parameters for engine control the parameters being related to the engine
    • F02D2200/10—Parameters related to the engine output, e.g. engine torque or engine speed
    • F02D2200/1006—Engine torque losses, e.g. friction or pumping losses or losses caused by external loads of accessories
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2200/00—Input parameters for engine control
    • F02D2200/02—Input parameters for engine control the parameters being related to the engine
    • F02D2200/10—Parameters related to the engine output, e.g. engine torque or engine speed
    • F02D2200/1012—Engine speed gradient
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D31/00—Use of speed-sensing governors to control combustion engines, not otherwise provided for
    • F02D31/001—Electric control of rotation speed
    • F02D31/007—Electric control of rotation speed controlling fuel supply
    • F02D31/008—Electric control of rotation speed controlling fuel supply for idle speed control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/04—Introducing corrections for particular operating conditions
    • F02D41/08—Introducing corrections for particular operating conditions for idling
    • F02D41/086—Introducing corrections for particular operating conditions for idling taking into account the temperature of the engine

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)

Abstract

The present invention relates to a method for controlling fuel injection in connection to engine start procedure. The method comprises the steps of: choosing (S1) a certain amount of fuel for injection to initiate said engine start procedure; and determining (S2) a resulting engine speed development based upon said certain amount of fuel. The method further comprises the steps of: determining (S3) the engine speed increase rate of said resulting engine speed development; and adapting (S4) the amount of fuel based upon said engine speed increase rate.The present invention also relates to a system for controlling fuel injection in connection to engine start procedure. The present invention also relates to a vehicle. The present invention also relates to a computer program and a computer program product.

Description

|\/IETHOD AND SYSTEM FOR CONTROLLING FUEL INJECTION INCONNECTION TO ENGINE START PROCEDURE TECHNICAL FIELD The invention relates to a method for controlling fuel injection in connection toengine start procedure according to the preamble of claim 1. The inventionalso relates to a system for controlling fuel injection in connection to enginestart procedure. The invention also relates to a vehicle. The invention inaddition relates to a computer program and a computer program product.
BACKG ROUND ART ln connection to the start procedure of an internal combustion engine theamount of fuel used need to be sufficient in order for the engine to start. lnorder to determine the amount of fuel to be used in an engine start procedurea calibrated engine water/oil temperature/engine speed map may be used.Determining the amount of fuel based on such calibrated data may howeverresult in overshoot of the engine speed in connection to reaching the idlespeed for engine start, and may also result in uneven control of the idle speed.
US20030047164 discloses a method in which the engine speed at an enginestart procedure is measured, wherein the measured value is compared to areference value, wherein the fuel may be modified based on a differencebetween the measured value and the reference value in order to improve reduction in emissions.
There is thus a need for improving control of fuel injection in connection toengine start procedure.
OBJECTS OF THE INVENTION An object of the present invention is to provide a method for controlling fuelinjection in connection to engine start procedure which facilitates improvingcontrol of engine start procedures.
An object of the present invention is to provide a method for controlling fuelinjection in connection to engine start procedure which facilitates control ofthe engine start so as to obtain a desired start behaviour of the engine.
An object of the present invention is to provide a method for controlling fuelinjection in connection to engine start procedure which facilitates control ofthe engine start so as to obtain start behaviour of the engine such that theengine starts within a desired time undesired overshoot of the engine speedduring the start procedure.
An object of the present invention is to provide a system for controlling fuelinjection in connection to engine start procedure which facilitates control ofthe engine start so as to obtain a desired start behaviour of the engine.
An object of the present invention is to provide a system for controlling fuelinjection in connection to engine start procedure which facilitates control ofthe engine start so as to obtain start behaviour of the engine such that theengine starts within a desired time undesired overshoot of the engine speedduring the start procedure.
SUMMARY OF THE INVENTION These and other objects, apparent from the following description, areachieved by a method, a system, a vehicle, a computer program and acomputer program product, as set out in the appended independent claims.
Preferred embodiments of the method and the system are defined in appended dependent claims.
Specifically an object of the invention is achieved by a method for controllingfuel injection in connection to engine start procedure. The method comprisesthe step of: choosing a certain amount of fuel for injection to initiate saidengine start procedure. Said chosen amount of fuel being based upon anestimated power demand for keeping said engine running at idle speed. Themethod further comprises the steps of: during engine idle speed of theengine start procedure after start of the engine determining an actual powerdemand required for keeping said engine running at idle speed based uponcurrent conditions comprising engine temperature; and adapting the amountof fuel based upon said determined actual power demand in a followingengine start procedure.
A first certain amount of fuel chosen for a first engine start procedure isaccording to an embodiment chosen taking current engine temperature intoaccount. A first certain amount of fuel chosen for a first engine startprocedure is thus chosen based upon the demanded power demand requiredfor keeping said engine running at idle speed.
The engine start procedure comprises the start of injection when said certainamount of fuel is injected and until the engine has started. The engine startprocedure comprises according to an embodiment a certain period of engineidle speed. The period from start of injection when said certain amount of fuelis injected to when the engine has started at idle speed is according to anembodiment denoted engine start development.
By thus adapting the amount of fuel based upon said determined actualpower demand in a following engine start procedure control of engine startprocedures are improved. By thus adapting the amount of fuel based uponsaid determined actual power demand in a following engine start procedure agood basis for choosing a suitable amount of fuel in a following engine start is obtained. Hereby control of the engine start so as to obtain a desired startbehaviour of the engine is improved in following engine start procedures.Hereby a starting behaviour which is repeatable may be obtained in anefficient way. Having repeated the adaption of amount of fuel in a fewfollowing engine start procedures the engine starting behaviour will beoptimized to the desired behaviour, i.e. the engine speed development duringthe engine start procedures will be repeatable. The behaviour of theparticular internal combustion engine during engine start procedures will berepeatable during the life time of the engine. Certain changes in the enginewith respect to ageing will be considered by performing said adaption ofamount of fuel. By thus adapting the amount of fuel based upon saiddetermined actual power demand in a following engine start procedure theneed for calibrating the amount of fuel for start procedures is reduced.
By thus adapting the amount of fuel based upon said determined actualpower demand in a following engine start procedure the engine speeddevelopment during the engine start procedure can be controlled such that adesired starting behaviour of the engine is obtained wherein the time forstarting the engine, i.e. the time for reaching the engine idle speed, does nottake too long, and wherein an overshoot behaviour with respect to saidengine speed can be reduced/mitigated/avoided.
According to an embodiment the method comprises the step of adapting thedetermined actual power demand for keeping the engine running at idlespeed to the engine speeds during the engine start procedure. Adapting thedetermined actual power demand for keeping the engine running at idlespeed the engine speeds during the engine start procedure, i.e. the enginespeed development during the engine start development, results in differenttorques which corresponds to a certain amount of fuel. Adapting the amountof fuel based upon said determined actual power demand required forkeeping said engine running at a certain idle speed in a following engine startprocedure is thus performed where the determined actual power demand for keeping the engine running at idle speed has been adapted to the engine speeds during the engine start procedure.
According to an embodiment of the method the step of adapting the amountof fuel based upon said actual power demand in a following engine startprocedure comprises the step of adapting the amount of fuel to currentconditions with respect to engine temperature in the following engine start.Hereby a more accurate amount of fuel may be chosen for that engine startthus facilitating improved engine start procedure. The amount of fuel adaptedbased upon the actual power demand in a following engine start procedurecomprises in addition to adapting the amount of fuel to current conditions withrespect to engine temperature in the following engine start taking the enginespeed of the engine start procedure into consideration.
According to an embodiment of the method the step of adapting the amountof fuel based upon said actual power demand in a following start takingcurrent conditions into account comprises: decreasing the amount of fuel ifthe power demand is lower than said estimated power demand, andincreasing the amount of fuel if power demand is higher than said estimatedpower demand. By thus taking the current conditions comprising enginetemperature into consideration a good estimation of the chosen amountbased upon determined actual power demand is facilitated.
According to an embodiment the method comprises the step of storing actualpower demands required for keeping said engine running at idle speed fordifferent current conditions comprising engine temperature, the actual powerdemands being determined during engine idle speed of the engine startprocedure after start of the engine in connection to different engine startprocedures so as to provide a basis for choosing the amount of fuel forinjection to initiate following engine start procedures. Hereby the powerdemand required for keeping the engine running at idle speed for the currentcondition of an engine start may be stored and made available for that startsuch that the adaptation of the amount of fuel can be made based upon a power demand determined for such conditions, the conditions comprising engine temperature.
The determined actual power demand for keeping the engine running at idlespeed is thus adapted to the engine speeds during an engine startprocedure, thus resulting in different torques which corresponds to a certain amount of fuel.
According to an embodiment of the method the step of determining an actualpower demand required for keeping said engine running at idle speed isperformed during idle speed when drivetrain is disengaged. Hereby a moreaccurate power demand is obtained.
According to an embodiment the method further comprises the steps of:determining a resulting engine speed development based upon said certainamount of fuel; determining the engine speed increase rate of said resultingengine speed development; and adapting the amount of fuel based upon said engine speed increase rate.
According to an embodiment a predicted engine speed development duringengine start procedure is determined based upon said engine speed increaserate, wherein the amount of fuel is adapted based upon the predicted engine speed development.
By thus adapting the amount of fuel based upon said engine speed increaserate control of the engine speed development during the engine startprocedure can be further improved such that a desired starting behaviour ofthe engine is obtained wherein the time for starting the engine, i.e. the timefor reaching the engine idle speed, does not take too long, and wherein anovershoot behaviour with respect to said engine speed can be reduced/mitigated/avoided. Hereby further improvement of a starting behaviour which is repeatable may be obtained in an efficient way.
Said adaption of the amount of fuel based upon said engine speed increaserate may be performed during the engine start procedure which thus furtherimproves the respective engine start procedure. Said adaption based uponsaid engine speed increase rate may also be taken into considerationtogether with the adaption based upon the determined actual power demandand current conditions in connection to a following engine start procedurewhere the certain amount of fuel chosen for injection in connection to thefollowing injection is adapted by adding or reducing the amount of fuel forthat following engine start procedure. Thus, hereby the engine speeddevelopment will be further improved in a following engine start procedure.Having repeated the adaption of amount of fuel in a few following engine startprocedures the engine starting behaviour will be optimized to the desiredbehaviour, i.e. the engine speed development during the engine startprocedures will be corresponding to the desired behaviour in order for theengine to start within a desired starting time avoiding overshoot behaviour ofthe engine speed. The behaviour of the particular internal combustion engineduring engine start procedures will be repeatable during the life time of theengine. Certain changes in the engine with respect to ageing will be considered by performing said adaption of amount of fuel.
According to an embodiment of the method the step of adapting the amountof fuel based upon the engine speed increase rate comprises: increasing theamount of fuel if the engine speed increase rate is too low indicating that theengine speed increases too slow so that the accumulated time before engineidle speed is obtained is too long, and decreasing the amount of fuel if theengine speed increase rate is too high indicating an overshoot behaviour withrespect to said engine speed. Hereby efficient adaption of amount of fuel isobtained such that the behaviour of the engine speed development duringthe engine start procedure corresponds to a desired starting behaviour of the engine is obtained.
According to an embodiment of the method the step of adapting the amountof fuel based upon the engine speed increase rate comprises adapting theamount of fuel for injection during the engine start procedure at a certainengine speed prior to reaching the demanded engine idle speed. By thusperforming possible adaption of amount of fuel at a certain engine speedprior to reaching the demanded engine idle speed the engine start procedurecan be controlled during a particular engine start procedure, thus facilitatingobtaining a desired engine start time avoiding extreme overshoot behaviourof the engine speed.
According to an embodiment of the method the step of adapting the amountof fuel based upon the engine speed increase rate comprises adapting saidcertain amount of fuel for injection to initiate said engine start procedure inaccordance with said adapted amount of fuel in a following engine startprocedure. According to an embodiment the adapted amount of fuel, i.e. acertain decreased amount or a certain increased amount of fuel, determinedin the previous engine start procedure is stored to be used in the followingengine start procedure by adding/reducing the certain amount of fuel used inthe previous starting procedure with this amount of fuel for the followingengine start procedure. Hereby the engine speed development will beimproved in a following engine start procedure as the amount of fuel usedhas been adapted to the behaviour, i.e. engine speed increase rate, of anearlier engine start procedure. Thus, the engine will have learned from anearlier engine start procedure such that an improved engine startingbehaviour may be obtained, thus facilitating further reducing possibleovershoot behaviour of the engine speed and improving the time for theengine speed to reach the engine idle speed and thus start of the engine.Thus, if a certain overshoot behaviour of the engine speed has beendetermined in an earlier engine start procedure the certain amount of fuel tobe injected in this following engine start procedure is reduced in accordancewith that overshoot behaviour so as to reduce/eliminate the overshoot behaviour in this engine start procedure.
According to an embodiment of the method the step of adapting the amountof fuel based upon the determined engine speed increase rate is performedin following engine start procedures. Hereby the speed development andhence the engine start behaviour will be improved and within a few enginestart procedures will have reached a very good level so that the startingbehaviour of the engine will be a desired starting behaviour giving a good anrepeatable feeling for a vehicle operator when starting the engine of thevehicle.
Specifically an object of the invention is achieved by a system for controllingfuel injection in connection to engine start procedure. The system comprisesmeans for choosing a certain amount of fuel for injection to initiate saidengine start procedure, said chosen amount of fuel being based upon anestimated power demand for keeping said engine running at idle speed. Thesystem further comprises means for determining, during engine idle speed ofthe engine start procedure after start of the engine, an actual power demandrequired for keeping said engine running at idle speed based upon currentconditions comprising engine temperature; and means for adapting theamount of fuel based upon said determined actual power demand in a following engine start procedure.
According to an embodiment of the system the means for adapting theamount of fuel based upon said actual power demand in a following enginestart procedure comprises adapting the amount of fuel to current conditionswith respect to engine temperature in the following engine start. Hereby amore accurate amount of fuel may be chosen for that engine start.
According to an embodiment of the system the means for adapting theamount of fuel based upon said actual power demand in a following starttaking current conditions into account comprises means for decreasing theamount of fuel if the power demand is lower than said estimated powerdemand, and means for increasing the amount of fuel if power demand is higher than said estimated power demand.
According to an embodiment of the system the means for storing actualpower demands required for keeping said engine running at idle speed fordifferent current conditions comprising engine temperature, the means fordetermining the actual power demands being arranged to determine thepower demands during engine idle speed of the engine start procedure afterstart of the engine in connection to different engine start procedures so as toprovide a basis for choosing the amount of fuel for injection to initiatefollowing engine start procedures.
According to an embodiment of the system the means for determining anactual power demand required for keeping said engine running at idle speed is arranged to be performed during idle speed when drivetrain is disengaged.
According to an embodiment the system comprises means for determining aresulting engine speed development based upon said certain amount of fuel;means for determining the engine speed increase rate of said resultingengine speed development; and means for adapting the amount of fuelbased upon said engine speed increase rate.
According to an embodiment of the system the means for adapting theamount of fuel based upon the engine speed increase rate comprises: meansfor increasing the amount of fuel if the engine speed increase rate is too lowindicating that the engine speed increases too slow so that the accumulatedtime before engine idle speed is obtained is too long, and means fordecreasing the amount of fuel if the engine speed increase rate is too high indicating an overshoot behaviour with respect to said engine speed.
According to an embodiment of the system the means for adapting theamount of fuel based upon the engine speed increase rate comprisesadapting the amount of fuel for injection during the engine start procedure at a certain engine speed prior to reaching the demanded engine idle speed.
According to an embodiment of the system the means for adapting theamount of fuel based upon the engine speed increase rate comprises 11 adapting said certain amount of fuel for injection to initiate said engine startprocedure in accordance with said adapted amount of fuel in a followingengine start procedure.
According to an embodiment of the system the means for adapting theamount of fuel based upon the determined engine speed increase rate is performed in following engine start procedures.
The system for controlling fuel injection in connection to engine startprocedure is adapted to perform the method as set out herein.
The system according to the invention has the advantages according to thecorresponding method.
Specifically an object of the invention is achieved by a vehicle comprising asystem according to the invention as set out herein.
Specifically an object of the invention is achieved by a computer program forcontrolling fuel injection in connection to engine start procedure, saidcomputer program comprising program code which, when run on anelectronic control unit or another computer connected to the electronic controlunit, causes the electronic control unit to perform the method according to the invenfion.
Specifically an object of the invention is achieved by a computer programproduct comprising a digital storage medium storing the computer program.
BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the present invention reference is made to thefollowing detailed description when read in conjunction with theaccompanying drawings, wherein like reference characters refer to like parts throughout the several views, and in which: 12 Fig. 1 schematically i||ustrates a side view of a vehicle according to the present invention; Fig. 2 schematically i||ustrates a function of an engine start procedure according to an embodiment of the present invention; Fig. 3 schematically i||ustrates amount of fuel as a function of engine speedfor different engine temperatures according to an embodiment of the present invenfion; Fig. 4 schematically i||ustrates the amount of fuel and engine speeddevelopment during an engine start procedure according to an exemplary embodiment of the present invention; Fig. 5 schematically i||ustrates a system for controlling fuel injection inconnection to engine start procedure according to an embodiment of the present invention; Fig. 6 schematically i||ustrates a block diagram of a method for controllingfuel injection in connection to engine start procedure according to an embodiment of the present invention; and Fig. 7 schematically i||ustrates a computer according to an embodiment of the present invention.
DETAILED DESCRIPTION Hereinafter the term “link” refers to a communication link which may be aphysical connector, such as an optoelectronic communication wire, or a non-physical connector such as a wireless connection, for example a radio or microwave link.
Hereinafter the term “engine temperature” refers to the engine water temperature and/or engine oil temperature. 13 Hereinafter the term “means for” e.g. in relation to “means for choosing acertain amount of fuel for injection”, “means for determining, during engineidle speed of the engine start procedure after start of the engine, an actualpower demand required for keeping said engine running at idle speed”,“means for adapting the amount of fuel based upon said determined actualpower demand in a following engine start procedure”, “means for determininga resulting engine speed development based upon said certain amount offuel”, “means for determining the engine speed increase rate of said resultingengine speed development”, and “for adapting the amount of fuel based upon said engine speed increase rate”.
The engine according to the present invention could be any suitable internalcombustion engine with any suitable number of cylinders. The internalcombustion engine according to the present invention could for example be a5-cylinder engine, a 6-cylinder engine or an 8-cylinder engine. The cylinderscould be in any suitable alignment, for example inline engine or a V-engine.The internal combustion engine according to the present invention could beany supercharged internal combustion engine such as a turbocharged internal combustion engine.
Fig. 1 schematically illustrates a side view of a vehicle 1 according to thepresent invention. The exemplified vehicle 1 is a heavy vehicle in the shapeof a truck. The vehicle according to the present invention could be anysuitable vehicle such as a bus or a car. The vehicle is driven by means of aninternal combustion engine. The vehicle 1 comprises a system I forcontrolling fuel injection in connection to engine start procedure according to an embodiment of the present invention.
Fig. 2 schematically illustrates a function of an engine start procedure according to an embodiment of the present invention. ln a first engine start procedure a certain amount of fuel for injection to initiatesaid engine start procedure is chosen. The box EF is according to an 14 embodiment set to 0 amount of fuel and the box EP1 is set to a fuel amountcorresponding to a demanded power required for keeping the engine runningat idle speed where current conditions such as engine temperature has beentaken into account. According to an example the box EP1 has been set to anamount of fuel corresponding to a demanded power of e.g. 10 kW, the amount of fuel according to an embodiment being 100 mg.
When the engine has reached engine idle speed it is observed in box IDLE.During engine idle speed of the engine start procedure after start of theengine an actual power demand required for keeping the engine running atidle speed is determined in box EP2 taking current conditions comprising thecurrent engine temperature into consideration. The amount of fuel basedupon said actual power demand is adapted in a following engine start procedure.
The amount of fuel adapted based upon the actual power demand in afollowing engine start procedure comprises adapting the amount of fuel tocurrent conditions with respect to engine temperature in the following engine start and for the engine speed of the engine start procedure.
The determined actual power demand for keeping the engine running at idlespeed is adapted to the engine speeds during the engine start procedure,thus resulting in different torques which corresponds to a certain amount of fuel.
Adapting the amount of fuel based upon said actual power demand in afollowing start taking current conditions into account comprises decreasingthe amount of fuel if the power demand is lower than the estimated powerdemand in a previous engine start procedure, and increasing the amount offuel if power demand is higher than said estimated power demand in a previous engine start procedure.
The starting amount of fuel of the box START is in this example 100 mg. The engine speed increase rate of said resulting engine speed development based upon the amount of fuel used in the box START for the engine start procedure is determined in E. lf the engine speed increase rate is too low indicating that the engine speedincreases too slow so that the accumulated time before engine idle speed isobtained is too long the amount of fuel is increased by means of the boxRAIVIP wherein a certain additional amount of fuel is added, e.g. 10 mg, fromthe box RAIVIP providing a ramp function such that the additional amount isadded to the box EF. This may be performed during the engine startprocedure at a certain engine speed and results in a higher amount of fuel atthe box Fuel for start.
For a following engine start procedure the added amount of fuel is taken intoconsideration such that, given the same conditions, in this example 100 + 10= 110 mg of fuel is used for the following engine start procedure. lf 110 mg of fuel used as the amount of fuel in the following engine startprocedure reveals an overshoot behaviour with respect to said engine speedthe amount of fuel is decreased during the engine start procedure at a certain engine speed.
An overshoot behaviour may be predicted in the box OS-P by predicting theengine speed development during the start procedure. lf an overshootbehaviour is predicted in OS-P the amount of fuel for injection during theengine start procedure may be reduced at a certain engine speed prior toreaching the demanded engine idle speed.
An overshoot behaviour may be determined in the box OS by determining the engine speed development during the start procedure.
For a following engine start procedure the reduced amount of fuel is takeninto consideration such that an amount of fuel lower than 110 mg is used byreducing that amount with the thus determined amount causing said overshoot behaviour of the engine speed. 16 Fig. 3 schematically illustrates amount of fuel as a function of engine speedfor different engine temperatures according to an embodiment of the present invenfion. ln this example a certain amount of fuel is chosen for a first engine startprocedure taking current engine temperature into account. The chosenamount of fuel is according to an embodiment based upon an estimatedpower demand for keeping said engine running at idle speed. Thus, for arelatively low engine temperature illustrated with a dotted line in fig. 3, wherea low temperature according to a certain situation could e.g. be below zerodegrees, a relatively higher amount of fuel is chosen. For a relatively highengine temperature illustrated with a chain line in fig. 3, where a hightemperature according to a situation could be above e.g. 100 degrees, a relatively lower amount of fuel is chosen.
The amount of fuel is adapted based upon the engine speed increase rateduring the engine start procedure at a certain engine speed prior to reachingthe demanded engine idle speed. ln this case the engine speed increase ratehas been determined to be too high indicating an overshoot behaviour withrespect to said engine speed, wherein, at a certain engine speed, e.g. about50 rpm before reaching idle speed, the amount of fuel is decreased so as toreduced/mitigate/eliminate the overshoot behaviour in connection to reachingthe idle speed. This is illustrated with the dotted vertical line with “adapted” infig. 3. By thus performing possible adaption of amount of fuel at a certainengine speed prior to reaching the demanded engine idle speed the enginestart procedure can be controlled during a particular engine start procedure,thus facilitating obtaining a desired engine start time avoiding extremeovershoot behaviour of the engine speed.
Fig. 4 schematically illustrates the amount of fuel and engine speeddevelopment during an engine start procedure according to an exemplary embodiment of the present invention. 17 ln this example in which the fuel injection in connection to engine startprocedure is controlled in accordance with an embodiment of the presentinvention a certain amount of fuel for injection to initiate engine startprocedure has been chosen as can be seen in the upper graph of fig. 4illustrating the amount of fuel during the engine start procedure. The chosenamount of fuel is according to an embodiment based upon an estimatedpower demand for keeping said engine running at idle speed. A resultingengine speed development is determined based upon said certain amount of fuel.
The engine speed increase rate of said resulting engine speed developmentis also determined. A predicted engine speed development is determinedbased upon the engine speed increase rate. The predicted engine speeddevelopment is illustrated as a dotted line and the actual engine speeddevelopment is illustrated as a solid line in the lower graph of fig. 4. Thepredicted engine speed development predicts an overshoot behaviour of theengine speed development in connection to reaching the idle speed. ln orderto reduce/limit/eliminate the overshoot behaviour the amount of fuel isadapted, i.e. in this case reduced, based upon said engine speed increaserate, i.e. based upon the predicted overshoot behaviour of the engine speeddevelopment. The reduction of fuel is performed a certain time before the idlespeed has been reached by means of a controlled decrease of fuel amount as shown in fig. 4.
Hereby the overshoot behaviour of the engine speed development is reducedas can be seen in the lower graph illustrating the actual engine speed development as a result of the reduction of fuel.
During engine idle speed of the engine start procedure after start of theengine determining the actual power demand required for keeping the enginerunning at idle speed based upon current conditions comprising enginetemperature is determined. ln a following engine start procedure the amount of fuel is adapted based upon said determined actual power taking current 18 conditions with respect to engine temperature in that following engine start into consideration.
Fig. 5 schematically illustrates a system I for controlling fuel injection inconnection to engine start procedure according to an embodiment of the present invention.The system I comprises an electronic control unit 100.
The system I comprises means 110 for choosing a certain amount of fuel forinjection to initiate said engine start procedure. The means 110 for choosinga certain amount of fuel is configured to taking current conditions intoaccount comprising current engine conditions comprising current enginetemperature and whether the engine is being started from a cold condition ora relatively warm condition such as relatively shortly after having been used.The means 110 for choosing a certain amount of fuel is, where applicable,configured to take an adaption of fuel performed in an earlier engine start procedure into account.
The means 110 for choosing a certain amount of fuel comprises means 112for determining the current engine temperature. The means 110 for choosinga certain amount of fuel comprises means 114 for determining the demandedpower demand required for keeping said engine running at idle speed basedupon current conditions comprising said engine temperature and may furthercomprise torque loss. A first certain amount of fuel chosen for a first enginestart procedure is according to an embodiment chosen based upon thedemanded power demand required for keeping said engine running at idle speed based upon.
The system I further comprises means 160 for determining, during engineidle speed of the engine start procedure after start of the engine, an actualpower demand required for keeping said engine running at idle speed basedupon the current engine temperature. The means 160 for determining an actual power demand required for keeping said engine running at idle speed 19 based upon the current engine temperature comprises means 162 fordetermining the current engine temperature. The means 162 may becomprised in or comprise the means 112. The means 160 for determining anactual power demand required for keeping said engine running at idle speedcomprises using predetermined data for demanded power for certain engine 126m pefatU TGS.
The system l further comprises means 170 for adapting the amount of fuelbased upon said determined actual power demand in a following engine start procedure.
The means 170 for adapting the amount of fuel based upon said actualpower demand in a following engine start procedure comprises adapting theamount of fuel to current conditions with respect to engine temperature in thefollowing engine start.
The means 170 for adapting the amount of fuel based upon said actualpower demand in a following start taking current conditions into accountcomprises means 172 for decreasing the amount of fuel if the power demandis lower than said estimated power demand The means 170 for adapting the amount of fuel based upon said actualpower demand in a following start taking current conditions into accountcomprises means 174 for increasing the amount of fuel if power demand ishigher than said estimated power demand.
The determined actual power demand for keeping the engine running at idlespeed is arranged to be adapted to the engine speeds during an engine startprocedure, thus resulting in different torques which corresponds to a certainamount of fuel. This certain amount of fuel is adapted taking currentconditions comprising engine temperature into consideration.
The means 170 for adapting the amount of fuel based upon said actualpower demand in a following engine start procedure comprises adapting the amount of fuel based upon an adaption of determined actual power demandfor keeping the engine running at idle speed to the engine speeds during theengine start procedure.
The system I comprises according to an embodiment means 190 for adaptingthe determined actual power demand for keeping the engine running at a certain idle speed to the engine speeds during the engine start procedure.
Adapting the determined actual power demand for keeping the enginerunning at idle speed the engine speeds during the engine start procedure,i.e. the engine speed development during the engine start development,results in different torques which corresponds to a certain amount of fuel.Adapting the amount of fuel based upon said determined actual powerdemand required for keeping said engine running at a certain idle speed in afollowing engine start procedure is thus performed where the determinedactual power demand for keeping the engine running at idle speed has been adapted to the engine speeds during the engine start procedure.
The system l further comprises means 180 for storing actual power demandsrequired for keeping said engine running at idle speed for different currentconditions comprising engine temperature. The means 160 for determiningthe actual power demands is arranged to determine the power demandsduring engine idle speed of the engine start procedure after start of theengine in connection to different engine start procedures so as to provide abasis for choosing the amount of fuel for injection to initiate following engine start procedures.
The means 180 for storing actual power demands comprises according to anembodiment internal storage means on board the vehicle. The internalstorage means may be any suitable means for storing information such as acontrol unit, a computer or the like. The internal storage means is accordingto an embodiment comprised in the electronic control unit 100. 21 The means 180 for storing actual power demands comprises according to anembodiment external storage means external to the vehicle. The externalstorage means may be any suitable external storage means such as a severunit, a personal computer, a tablet, a so called cloud-storage, a laptop and/ora smartphone or the like.
By thus storing actual power demands required for keeping said enginerunning at idle speed for different current conditions comprising enginetemperature, the power demand required for keeping the engine running atidle speed for the current condition of an engine start may be stored andmade available for that start such that the adaptation of the amount of fuelcan be made based upon a power demand determined for such conditions,the conditions comprising engine temperature.
The system I comprises means 120 for determining a resulting engine speeddevelopment based upon said certain amount of fuel.
The means 120 for determining a resulting engine speed development basedupon said certain amount of fuel may comprise any suitable detector unit fordetecting the engine speed development during engine start procedure.
The system I comprises means 130 for determining the engine speed increase rate of said resulting engine speed development.
The means 130 for determining the engine speed increase rate maycomprise any suitable means for determining the engine speed increase ratebased upon said engine speed development. The means 130 comprises acalculation unit for calculating the engine speed increase rate based upon theengine speed development during the engine start procedure. The means130 may be comprised in the electronic control unit 100.
The system I comprises means 140 for adapting the amount of fuel based upon said engine speed increase rate. 22 The means 140 for adapting the amount of fuel based upon said enginespeed increase rate comprises according to an embodiment means 140a fordetermining a predicted engine speed development during the engine startprocedure. The means 140a for determining a predicted engine speeddevelopment during the engine start procedure may comprise any suitablemeans for predicting an engine speed development. The means 140a fordetermining a predicted engine speed development comprises according toan embodiment said electronic control unit 100.
The means 140 for adapting the amount of fuel based upon the engine speedincrease rate comprises means 142 for increasing the amount of fuel if theengine speed increase rate is too low indicating that the engine speedincreases too slow so that the accumulated time before engine idle speed isobtained is too long. The means 142 for increasing the amount of fuelcomprises according to an embodiment fuel injections means comprising afuel injector of the engine, the fuel injector being arranged to increase the amount injected.
The means 140 for adapting the amount of fuel based upon the engine speedincrease rate comprises means 144 for decreasing the amount of fuel if theengine speed increase rate is too high indicating an overshoot behaviour withrespect to said engine speed. The means 144 for decreasing the amount offuel comprises according to an embodiment fuel injections means comprisinga fuel injector of the engine, the fuel injector being arranged to decrease/stop the amount injected.
The means 140 for adapting the amount of fuel based upon the engine speedincrease rate comprises adapting the amount of fuel for injection during theengine start procedure at a certain engine speed prior to reaching thedemanded engine idle speed. The means 140 for adapting the amount of fuelbased upon the engine speed increase rate comprises according to anembodiment determining whether the predicted engine speed developmentduring the engine start procedure is predicted to result in an overshoot or is 23 predicted to result in the accumulated time before engine idle speed is obtained will be too long.
The means 140 for adapting the amount of fuel based upon the engine speedincrease rate comprises adapting said certain amount of fuel for injection toinitiate said engine start procedure in accordance with said adapted amountof fuel in a following engine start procedure. The means 140 for adapting theamount of fuel based upon the engine speed increase rate comprisesadapting said certain amount of fuel for injection to initiate said engine startprocedure in accordance with said adapted amount of fuel in a followingengine start procedure comprises adding or reducing the certain amount offuel used in a previous starting procedure with the determined amount of fuelwith which the fuel is intended to be adapted for the following engine start procedure.
The system I comprises according to an embodiment means 150 for storingthe adapted amount of fuel, i.e. a certain decreased amount or a certainincreased amount of fuel, determined in a previous engine start procedure tobe used in the following engine start procedure by adding/reducing thecertain amount of fuel used in the previous starting procedure with this amount of fuel for the following engine start procedure.
The means 140 for adapting the amount of fuel based upon the determinedengine speed increase rate is performed in following engine start procedures.
The electronic control unit 100 is operably connected to the means 110 forchoosing a certain amount of fuel for injection to initiate said engine startprocedure via a link 10a. The electronic control unit 100 is via the link 10aarranged to send a signal to said means 110 representing data for amount offuel comprising data for current conditions and possible data for earlierengine start procedure comprising data for adapted amount of fuel in earlierengine start procedure. 24 The electronic control unit 100 is operably connected to the means 110 forchoosing a certain amount of fuel for injection to initiate said engine startprocedure via a link 10b. The electronic control unit 100 is via the link 10barranged to receive a signal from said means 110 representing data for chosen amount of fuel.
The electronic control unit 100 is operably connected to the means 112 fordetermining the current engine temperature via a link 12. The electroniccontrol unit 100 is via the link 12 arranged to receive a signal from said means 112 representing data for current engine temperature.
The electronic control unit 100 is operably connected to the means 114 fordetermining the demanded power demand required for keeping said enginerunning at idle speed based upon said engine temperature via a link 14a. Theelectronic control unit 100 is via the link 14a arranged to send a signal to said means 114a representing data for current engine temperature.
The electronic control unit 100 is operably connected to the means 114 fordetermining the demanded power demand required for keeping said enginerunning at idle speed based upon said engine temperature via a link 14b. Theelectronic control unit 100 is via the link 14b arranged to receive a signal fromsaid means 114b representing data for demanded power demand requiredfor keeping said engine running at idle speed based upon said engine te mpefatU FG.
The electronic control unit 100 is operably connected to the means 160 fordetermining, during engine idle speed of the engine start procedure after startof the engine, an actual power demand required for keeping said enginerunning at idle speed based upon the current engine temperature via a link60a. The electronic control unit 100 is via the link 60a arranged to send asignal to said means 160 representing data for current conditions comprising engine temperature.
The electronic control unit 100 is operably connected to the means 160 fordetermining, during engine idle speed of the engine start procedure after startof the engine, an actual power demand required for keeping said enginerunning at idle speed based upon current conditions comprising enginetemperature via a link 60b. The electronic control unit 100 is via the link 60barranged to receive a signal from said means 160 representing data foractual power demand required for keeping said engine running at idle speed.
The electronic control unit 100 is operably connected to the means 162 fordetermining the current engine temperature via a link 62. The electroniccontrol unit 100 is via the link 62 arranged to receive a signal from said means 162 representing data for current engine temperature.
The electronic control unit 100 is operably connected to the means 170 foradapting the amount of fuel for keeping said engine running at idle speedbased upon said actual power demand via a link 70a. The electronic controlunit 100 is via the link 70a arranged to send a signal to said means 170representing data for actual power demand.
The electronic control unit 100 is operably connected to the means 170 foradapting the amount of fuel for keeping said engine running at idle speedbased upon said actual power demand via a link 70b. The electronic controlunit 100 is via the link 70b arranged to receive a signal from said means 170representing data for adapting the amount of fuel.
The electronic control unit 100 is operably connected to the means 190 foradapting the determined actual power demand for keeping the enginerunning at a certain idle speed to the engine speeds during the engine startprocedure via a link 90a. The electronic control unit 100 is via the link 90aarranged to send a signal to said means 190 representing data fordetermined actual power at a certain idle speed and data for engine speedsduring the engine start procedure. 26 The electronic control unit 100 is operably connected to the means 190 foradapting the determined actual power demand for keeping the enginerunning at a certain idle speed to the engine speeds during the engine startprocedure via a link 90b. The electronic control unit 100 is via the link 90barranged to receive a signal from said means 190 representing data for adapted actual power demand.
The electronic control unit 100 is operably connected to the means 180 forstoring actual power demands required for keeping said engine running atidle speed for different current conditions comprising engine temperature viaa link 80a. The electronic control unit 100 is via the link 80a arranged to senda signal to said means 180 representing data determined actual powerdemands required for keeping said engine running at idle speed for different current conditions comprising engine temperature.
The electronic control unit 100 is operably connected to the means 180 forstoring actual power demands required for keeping said engine running atidle speed for different current conditions comprising engine temperature viaa link 80b. The electronic control unit 100 is via the link 80b arranged toreceive a signal from said means 180 representing data for actual power demand for current condition comprising engine temperature.
The electronic control unit 100 is operably connected to the means 120 fordetermining a resulting engine speed development based upon said certainamount of fuel via a link 20. The electronic control unit 100 is via the link 20arranged to receive a signal from said means 120 representing data forengine speed during the engine start procedure.
The electronic control unit 100 is operably connected to the means 130 fordetermining the engine speed increase rate of said resulting engine speeddevelopment via a link 30a. The electronic control unit 100 is via the link 30aarranged to send a signal to said means 130 representing data for enginespeed during the engine start procedure. 27 The electronic control unit 100 is operably connected to the means 130 fordetermining the engine speed increase rate of said resulting engine speeddevelopment via a link 30b. The electronic control unit 100 is via the link 14barranged to receive a signal from said means 30b representing data fordemanded power demand required for keeping said engine running at idle engine speed increase rate.
The electronic control unit 100 is operably connected to the means 140a fordetermining a predicted engine speed development rate via a link 40a-1. Theelectronic control unit 100 is via the link 40a-1 arranged to send a signal tosaid means 140a representing data for engine speed increase rate.
The electronic control unit 100 is operably connected to the means 140a fordetermining a predicted engine speed development via a link 40a-2. Theelectronic control unit 100 is via the link 40a-2 arranged to receive a signalfrom said means 140a representing data for predicted engine speeddevelopment.
The electronic control unit 100 is operably connected to the means 140 foradapting the amount of fuel based upon said engine speed increase rate viaa link 40-1. The electronic control unit 100 is via the link 40-1 arranged tosend a signal to said means 140 representing data for engine speed increaserate and/or data for predicted engine speed development.
The electronic control unit 100 is operably connected to the means 140 foradapting the amount of fuel based upon said engine speed increase rate viaa link 40-2. The electronic control unit 100 is via the link 40-2 arranged toreceive a signal from said means 140 representing data for adapting the amount of fuel.
The electronic control unit 100 is operably connected to the means 142 forincreasing the amount of fuel if the engine speed increase rate is too lowindicating that the engine speed increases too slow so that the accumulatedtime before engine idle speed is obtained is too long via a link 42a. The 28 electronic control unit 100 is via the link 42a arranged to send a signal to saidmeans 142 representing data for engine speed increase rate and/or data forpredicted engine speed development.
The electronic control unit 100 is operably connected to the means 142 forincreasing the amount of fuel if the engine speed increase rate is too lowindicating that the engine speed increases too slow so that the accumulatedtime before engine idle speed is obtained is too long via a link 42b. Theelectronic control unit 100 is via the link 42b arranged to receive a signal from said means 142 representing data for increasing the amount of fuel.
The electronic control unit 100 is operably connected to the means 144 fordecreasing the amount of fuel if the engine speed increase rate is too highindicating an overshoot behaviour with respect to said engine speed via a link44a. The electronic control unit 100 is via the link 44a arranged to send asignal to said means 144 representing data for engine speed increase rate and/or data for predicted engine speed development.
The electronic control unit 100 is operably connected to the means 144 fordecreasing the amount of fuel if the engine speed increase rate is too highindicating an overshoot behaviour with respect to said engine speed via a link44b. The electronic control unit 100 is via the link 44b arranged to receive asignal from said means 142 representing data for decreasing the amount of fuel.
The electronic control unit 100 is operably connected to the means 150 forstoring the adapted amount of fuel determined in a previous engine startprocedure via a link 50a. The electronic control unit 100 is via the link 50aarranged to send a signal to said means 150 representing data for adapted amount of fuel determined in a previous engine start procedure.
The electronic control unit 100 is operably connected to the means 150 forstoring the adapted amount of fuel determined in a previous engine startprocedure via a link 50b. The electronic control unit 100 is via the link 50b 29 arranged to receive a signal from said means 150 representing data for adapted amount of fuel to be used in a following engine start procedure.
Fig. 6 schematically illustrates a block diagram of a method for controllingfuel injection in connection to engine start procedure according to an embodiment of the present invention.
According to the embodiment the method for controlling fuel injection inconnection to engine start procedure according to an embodiment of thepresent invention comprises a step S1. ln this step a certain amount of fuelfor injection to initiate said engine start procedure is chosen, said chosenamount of fuel being based upon an estimated power demand for keeping said engine running at idle speed.
According to the embodiment the method for controlling fuel injection inconnection to engine start procedure according to an embodiment of thepresent invention comprises a step S2. ln this step an actual power demandrequired for keeping said engine running at idle speed is determined duringengine idle speed of the engine start procedure after start of the enginebased upon current conditions comprising engine temperature.
According to the embodiment the method for controlling fuel injection inconnection to engine start procedure according to an embodiment of thepresent invention comprises a step S3. ln this step the amount of fuel isadapted based upon said determined actual power demand in a followingengine start procedure.
A first certain amount of fuel chosen for a first engine start procedure isaccording to an embodiment chosen taking current engine temperature intoaccount. A first certain amount of fuel chosen for a first engine startprocedure is thus chosen based upon the demanded power demand required for keeping said engine running at idle speed.
The engine start procedure comprises the start of injection when said certainamount of fuel is injected and until the engine has started. The engine startprocedure comprises according to an embodiment a certain period of engineidle speed. The period from start of injection when said certain amount of fuelis injected to when the engine has started at idle speed is according to an embodiment denoted engine start development.
By thus adapting the amount of fuel based upon said determined actualpower demand in a following engine start procedure control of engine startprocedures are improved. By thus adapting the amount of fuel based uponsaid determined actual power demand in a following engine start procedure agood basis for choosing a suitable amount of fuel in a following engine startis obtained. Hereby control of the engine start so as to obtain a desired startbehaviour of the engine is improved in following engine start procedures.Hereby a starting behaviour which is repeatable may be obtained in anefficient way. Having repeated the adaption of amount of fuel in a fewfollowing engine start procedures the engine starting behaviour will beoptimized to the desired behaviour, i.e. the engine speed development duringthe engine start procedures will be repeatable. The behaviour of theparticular internal combustion engine during engine start procedures will berepeatable during the life time of the engine. Certain changes in the enginewith respect to ageing will be considered by performing said adaption of amount of fuel.
According to an embodiment the method comprises the step of adapting thedetermined actual power demand for keeping the engine running at idlespeed to the engine speeds during the engine start procedure. Adapting thedetermined actual power demand for keeping the engine running at idlespeed the engine speeds during the engine start procedure, i.e. the enginespeed development during the engine start development, results in differenttorques which corresponds to a certain amount of fuel. Adapting the amountof fuel based upon said determined actual power demand required for 31 keeping said engine running at a certain idle speed in a following engine startprocedure is thus performed where the determined actual power demand forkeeping the engine running at idle speed has been adapted to the enginespeeds during the engine start procedure.
According to an embodiment of the method the step of adapting the amountof fuel based upon said actual power demand in a following engine startprocedure comprises the step of adapting the amount of fuel to currentconditions with respect to engine temperature in the following engine start.Hereby a more accurate amount of fuel may be chosen for that engine startthus facilitating improved engine start procedure. The amount of fuel adaptedbased upon the actual power demand in a following engine start procedurecomprises in addition to adapting the amount of fuel to current conditions withrespect to engine temperature in the following engine start taking the enginespeed of the engine start procedure into consideration.
According to an embodiment of the method the step of adapting the amountof fuel based upon said actual power demand in a following start takingcurrent conditions into account comprises: decreasing the amount of fuel ifthe power demand is lower than said estimated power demand, andincreasing the amount of fuel if power demand is higher than said estimated power demand.
According to an embodiment the method comprises the step of storing actualpower demands required for keeping said engine running at idle speed fordifferent current conditions comprising engine temperature, the actual powerdemands being determined during engine idle speed of the engine startprocedure after start of the engine in connection to different engine startprocedures so as to provide a basis for choosing the amount of fuel forinjection to initiate following engine start procedures. Hereby the powerdemand required for keeping the engine running at idle speed for the currentcondition of an engine start may be stored and made available for that startsuch that the adaptation of the amount of fuel can be made based upon a 32 power demand determined for such conditions, the conditions comprising engine temperature.
The determined actual power demand for keeping the engine running at idlespeed is thus adapted to the engine speeds during an engine startprocedure, thus resulting in different torques which corresponds to a certain amount of fuel.
According to an embodiment of the method the step of determining an actualpower demand required for keeping said engine running at idle speed isperformed during idle speed when drivetrain is disengaged.
According to an embodiment the method further comprises the steps of:determining a resulting engine speed development based upon said certainamount of fuel; determining the engine speed increase rate of said resultingengine speed development; and adapting the amount of fuel based upon said engine speed increase rate.
According to an embodiment a predicted engine speed development duringengine start procedure is determined based upon said engine speed increaserate, wherein the amount of fuel is adapted based upon the predicted enginespeed development.
Said adaption of the amount of fuel based upon said engine speed increaserate may be performed during the engine start procedure which thus furtherimproves the respective engine start procedure. Said adaption based uponsaid engine speed increase rate may also be taken into considerationtogether with the adaption based upon the determined actual power demandand current conditions in connection to a following engine start procedurewhere the certain amount of fuel chosen for injection in connection to thefollowing injection is adapted by adding or reducing the amount of fuel forthat following engine start procedure. Thus, hereby the engine speeddevelopment will be further improved in a following engine start procedure.Having repeated the adaption of amount of fuel in a few following engine start 33 procedures the engine starting behaviour will be optimized to the desiredbehaviour, i.e. the engine speed development during the engine startprocedures will be corresponding to the desired behaviour in order for theengine to start within a desired starting time avoiding overshoot behaviour ofthe engine speed. The behaviour of the particular internal combustion engineduring engine start procedures will be repeatable during the life time of theengine. Certain changes in the engine with respect to ageing will be considered by performing said adaption of amount of fuel.
According to an embodiment of the method the step of adapting the amountof fuel based upon the engine speed increase rate comprises: increasing theamount of fuel if the engine speed increase rate is too low indicating that theengine speed increases too slow so that the accumulated time before engineidle speed is obtained is too long, and decreasing the amount of fuel if theengine speed increase rate is too high indicating an overshoot behaviour with respect to said engine speed.
According to an embodiment of the method the step of adapting the amountof fuel based upon the engine speed increase rate comprises adapting theamount of fuel for injection during the engine start procedure at a certainengine speed prior to reaching the demanded engine idle speed. By thusperforming possible adaption of amount of fuel at a certain engine speedprior to reaching the demanded engine idle speed the engine start procedurecan be controlled during a particular engine start procedure, thus facilitatingobtaining a desired engine start time avoiding extreme overshoot behaviour of the engine speed.
According to an embodiment of the method the step of adapting the amountof fuel based upon the engine speed increase rate comprises adapting saidcertain amount of fuel for injection to initiate said engine start procedure inaccordance with said adapted amount of fuel in a following engine startprocedure. According to an embodiment the adapted amount of fuel, i.e. a certain decreased amount or a certain increased amount of fuel, determined 34 in the previous engine start procedure is stored to be used in the followingengine start procedure by adding/reducing the certain amount of fuel used inthe previous starting procedure with this amount of fuel for the followingengine start procedure.
According to an embodiment of the method the step of adapting the amountof fuel based upon the determined engine speed increase rate is performedin following engine start procedures. Hereby the speed development andhence the engine start behaviour will be improved and within a few enginestart procedures will have reached a very good level so that the startingbehaviour of the engine will be a desired starting behaviour giving a good anrepeatable feeling for a vehicle operator when starting the engine of thevehicle.
With reference to figure 7, a diagram of an apparatus 500 is shown. Thesystem l described with reference to fig. 5 may according to an embodimentcomprise apparatus 500. Apparatus 500 comprises a non-volatile memory520, a data processing device 510 and a read/write memory 550. Non-volatile memory 520 has a first memory portion 530 wherein a computerprogram, such as an operating system, is stored for controlling the function ofapparatus 500. Further, apparatus 500 comprises a bus controller, a serialcommunication port, I/O-means, an A/D-converter, a time date entry andtransmission unit, an event counter and an interrupt controller (not shown).
Non-volatile memory 520 also has a second memory portion 540.
A computer program P is provided comprising routines for controlling fuelinjection in connection to engine start procedure.
The program P comprises routines for during engine idle speed of the enginestart procedure after start of the engine determining an actual power demandrequired for keeping said engine running at idle speed based upon currentconditions comprising engine temperature. The program P comprisesroutines for adapting the amount of fuel based upon said determined actual power demand in a following engine start procedure. The routines foradapting the amount of fuel based upon said determined actual powerdemand in a following engine start procedure comprises routines for adaptingthe amount of fuel to current conditions with respect to engine temperature inthe following engine start. The routines for adapting the amount of fuel basedupon said determined actual power demand in a following engine startprocedure taking current conditions into account comprises routines fordecreasing the amount of fuel if the power demand is lower than saidestimated power demand, and comprises routines for increasing the amountof fuel if power demand is higher than said estimated power demand. Theprogram P comprises routines for storing actual power demands required forkeeping said engine running at idle speed for different current conditionscomprising engine temperature, the actual power demands being determinedduring engine idle speed of the engine start procedure after start of theengine in connection to different engine start procedures so as to provide abasis for choosing the amount of fuel for injection to initiate following enginestart procedures. The program P comprises routines for choosing a certainamount of fuel for injection to initiate said engine start procedure. Theprogram P comprises routines for determining a resulting engine speeddevelopment based upon said certain amount of fuel. The program Pcomprises routines for determining the engine speed increase rate of saidresulting engine speed development. The program P comprises routines foradapting the amount of fuel based upon said engine speed increase rate.The routines for adapting the amount of fuel based upon the engine speedincrease rate comprises routines for adapting the amount of fuel for injectionduring the engine start procedure at a certain engine speed prior to reachingthe demanded engine idle speed. The routines for adapting the amount offuel based upon the engine speed increase rate comprises routines foradapting said certain amount of fuel for injection to initiate said engine startprocedure in accordance with said adapted amount of fuel in a followingengine start procedure taking current conditions comprising engine temperature into account. The computer program P may be stored in an 36 executable manner or in a compressed condition in a separate memory 560 and/or in read/write memory 550.
When it is stated that data processing device 510 performs a certain functionit should be understood that data processing device 510 performs a certainpart of the program which is stored in separate memory 560, or a certain part of the program which is stored in read/write memory 550.
Data processing device 510 may communicate with a data communicationsport 599 by means of a data bus 515. Non-volatile memory 520 is adaptedfor communication with data processing device 510 via a data bus 512.Separate memory 560 is adapted for communication with data processingdevice 510 via a data bus 511. Read/write memory 550 is adapted forcommunication with data processing device 510 via a data bus 514. To thedata communications port 599 e.g. the links connected to the control units100 may be connected.
When data is received on data port 599 it is temporarily stored in secondmemory portion 540. When the received input data has been temporarilystored, data processing device 510 is set up to perform execution of code ina manner described above. The signals received on data port 599 can beused by apparatus 500 for choosing a certain amount of fuel for injection toinitiate said engine start procedure, said chosen amount of fuel being basedupon an estimated power demand for keeping said engine running at idlespeed. The signals received on data port 599 can be used by apparatus 500for during engine idle speed of the engine start procedure after start of theengine determining an actual power demand required for keeping saidengine running at idle speed based upon current conditions comprisingengine temperature. The signals received on data port 599 can be used byapparatus 500 for adapting the amount of fuel based upon said determinedactual power demand in a following engine start procedure. The signals usedfor adapting the amount of fuel based upon said determined actual powerdemand in a following engine start procedure are used for adapting the 37 amount of fuel to current conditions with respect to engine temperature in thefollowing engine start. The signals used for adapting the amount of fuelbased upon said determined actual power demand in a following engine startprocedure taking current conditions into account are used for decreasing theamount of fuel if the power demand is lower than said estimated powerdemand, and are used for increasing the amount of fuel if power demand ishigher than said estimated power demand. The signals received on data port599 can be used by apparatus 500 for storing actual power demandsrequired for keeping said engine running at idle speed for different currentconditions comprising engine temperature, the actual power demands beingdetermined during engine idle speed of the engine start procedure after startof the engine in connection to different engine start procedures so as toprovide a basis for choosing the amount of fuel for injection to initiatefollowing engine start procedures. The signals received on data port 599 canbe used by apparatus 500 for determining a resulting engine speeddevelopment based upon said certain amount of fuel. The signals receivedon data port 599 can be used by apparatus 500 for determining the enginespeed increase rate of said resulting engine speed development. The signalsreceived on data port 599 can be used by apparatus 500 for adapting theamount of fuel based upon said engine speed increase rate. The signalsused for adapting the amount of fuel based upon the engine speed increaserate are used for adapting the amount of fuel for injection during the enginestart procedure at a certain engine speed prior to reaching the demandedengine idle speed. The signals used for adapting the amount of fuel basedupon the engine speed increase rate are used for adapting said certainamount of fuel for injection to initiate said engine start procedure inaccordance with said adapted amount of fuel in a following engine startprocedure taking current conditions comprising engine temperature into aCCOUnt.
Parts of the methods described herein can be performed by apparatus 500 by means of data processing device 510 running the program stored in 38 separate memory 560 or read/write memory 550. When apparatus 500 runs the program, parts of the methods described herein are executed.
The foregoing description of the preferred embodiments of the presentinvention has been provided for the purposes of illustration and description. ltis not intended to be exhaustive or to limit the invention to the precise formsdisclosed. Obviously, many modifications and variations will be apparent topractitioners skilled in the art. The embodiments were chosen and describedin order to best explain the principles of the invention and its practicalapplications, thereby enabling others skilled in the art to understand theinvention for various embodiments and with the various modifications as are suited to the particular use contemplated.

Claims (21)

39 CLAIIVIS
1. A method for controlling fuel injection in connection to engine startprocedure, comprising the steps of: choosing (S1) a certain amount of fuel forinjection to initiate said engine start procedure; characterized in that saidchosen amount of fuel is based upon an estimated power demand forkeeping said engine running at idle speed, the method further comprising thesteps of: - during engine idle speed of the engine start procedure after start of theengine determining (S2) an actual power demand required for keeping saidengine running at idle speed based upon current conditions comprisingengine temperature; - adapting (S3) the amount of fuel based upon said determined actual power demand in a following engine start procedure.
2. A method according to claim 1, wherein the step of adapting the amountof fuel based upon said actual power demand in a following engine startprocedure comprises the step of adapting the amount of fuel to currentconditions with respect to engine temperature in the following engine start.
3. A method according to claim 1 or 2, wherein the step of adapting theamount of fuel based upon said actual power demand in a following starttaking current conditions into account comprises: decreasing the amount offuel if the power demand is lower than said estimated power demand, andincreasing the amount of fuel if power demand is higher than said estimated power demand.
4. A method according to any of claims 1-3, comprising the step of storingactual power demands required for keeping said engine running at idle speedfor different current conditions comprising engine temperature, the actualpower demands being determined during engine idle speed of the engine start procedure after start of the engine in connection to different engine start procedures so as to provide a basis for choosing the amount of fuel for injection to initiate following engine start procedures.
5. A method according to any of claims 1-4, wherein the step of determiningan actual power demand required for keeping said engine running at idlespeed is performed during idle speed when drivetrain is disengaged.
6. A method according to any of claims 1-5, comprising the steps of: - determining a resulting engine speed development during the enginestart procedure based upon said certain amount of fuel; - determining the engine speed increase rate of said resulting enginespeed development; and - adapting the amount of fuel based upon said engine speed increase rate.
7. A method according to claim 6, wherein the step of adapting the amountof fuel based upon the engine speed increase rate comprises: increasing theamount of fuel if the engine speed increase rate is too low indicating that theengine speed increases too slow so that the accumulated time before engineidle speed is obtained is too long, and decreasing the amount of fuel if theengine speed increase rate is too high indicating an overshoot behaviour with respect to said engine speed.
8. A method according to claim 6 or 7, wherein the step of adapting theamount of fuel based upon the engine speed increase rate comprisesadapting the amount of fuel for injection during the engine start procedure ata certain engine speed prior to reaching the demanded engine idle speed.
9. A method according to any of claims 6-8, wherein the step of adaptingthe amount of fuel based upon the engine speed increase rate comprisesadapting said certain amount of fuel for injection to initiate said engine startprocedure in accordance with said adapted amount of fuel in a followingengine start procedure taking current conditions comprising engine tempefatUfe lntO aCCOUnt. 41
10. A system (l) for controlling fuel injection in connection to engine startprocedure, comprising means (110) for choosing a certain amount of fuel forinjection to initiate said engine start procedure; characterized in that saidchosen amount of fuel is based upon an estimated power demand forkeeping said engine running at idle speed, the system further comprisingmeans (160) for determining, during engine idle speed of the engine startprocedure after start of the engine, an actual power demand required forkeeping said engine running at idle speed based upon current conditionscomprising engine temperature; and means (170) for adapting the amount offuel based upon said determined actual power demand in a following engine start procedure.
11. A system according to claim 10, wherein the means (170) for adaptingthe amount of fuel based upon said actual power demand in a followingengine start procedure comprises the step of adapting the amount of fuel tocurrent conditions with respect to engine temperature in the following enginestart.
12.A system according to claim 10 or 11, wherein the means (170) foradapting the amount of fuel based upon said actual power demand in afollowing start taking current conditions into account comprises means (172)for decreasing the amount of fuel if the power demand is lower than saidestimated power demand, and means (174) for increasing the amount of fuelif power demand is higher than said estimated power demand.
13.A system according to any of claims 10-12, means (180) for storingactual power demands required for keeping said engine running at idle speedfor different current conditions comprising engine temperature, the means(160) for determining the actual power demands being arranged to determinethe power demands during engine idle speed of the engine start procedureafter start of the engine in connection to different engine start procedures soas to provide a basis for choosing the amount of fuel for injection to initiate following engine start procedures. 42
14. A system according to any of claims 10-13, wherein the means (160) fordetermining an actual power demand required for keeping said enginerunning at idle speed is arranged to be performed during idle speed when drivetrain is disengaged.
15. A system according to any of claims 10-14, comprising means (120) fordetermining a resulting engine speed development based upon said certainamount of fuel; means (130) for determining the engine speed increase rateof said resulting engine speed development; and means (140) for adaptingthe amount of fuel based upon said engine speed increase rate.
16. A system according to claim 15, wherein the means (140) for adaptingthe amount of fuel based upon the engine speed increase rate comprises:means (142) for increasing the amount of fuel if the engine speed increaserate is too low indicating that the engine speed increases too slow so that theaccumulated time before engine idle speed is obtained is too long, andmeans (144) for decreasing the amount of fuel if the engine speed increaserate is too high indicating an overshoot behaviour with respect to said engine speed.
17.A system according to claim 15 or 16, wherein the means (140) foradapting the amount of fuel based upon the engine speed increase ratecomprises adapting the amount of fuel for injection during the engine startprocedure at a certain engine speed prior to reaching the demanded engine idle speed.
18. A system according to any of claims 15-17, ,wherein the means (140) foradapting the amount of fuel based upon the engine speed increase ratecomprises adapting said certain amount of fuel for injection to initiate saidengine start procedure in accordance with said adapted amount of fuel in a following engine start procedure.
19. A vehicle (1) comprising a system (l) according to any of claims 10-18. 43
20.A computer program (P) for, said computer program (P) comprisingprogram code which, when run on an electronic control unit (100) or anothercomputer (500) connected to the electronic control unit (100), causes the electronic control unit to perform the steps according to claim 1-9.
21. A computer program product comprising a digital storage medium storing the computer program according to claim 20.
SE1650887A 2016-06-22 2016-06-22 Method and system for controlling fuel injection in connection to engine start procedure SE541113C2 (en)

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DE102017005860.1A DE102017005860A1 (en) 2016-06-22 2017-06-21 A method and system for controlling fuel injection in conjunction with an engine starting operation

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FR3095009B1 (en) * 2019-04-09 2021-03-12 Psa Automobiles Sa PROCEDURE FOR CORRECTING A RICH FUEL DURING A COLD START
EP4163486A1 (en) * 2021-10-06 2023-04-12 Volvo Truck Corporation A method for controlling a rotational speed of an output shaft of a propulsion unit

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JPS5746031A (en) * 1980-09-01 1982-03-16 Toyota Motor Corp Method of controlling supplied quantity of fuel to internal combustion engine
DE4329448B4 (en) * 1993-09-01 2007-08-23 Robert Bosch Gmbh Method and device for metering fuel in the starting case of an internal combustion engine
DE19740192C2 (en) * 1997-09-12 2000-03-16 Siemens Ag Method for starting an internal combustion engine
JPH11236842A (en) * 1998-02-24 1999-08-31 Isuzu Motors Ltd Electronic control fuel injection device for diesel engine
JP2002030962A (en) * 2000-07-14 2002-01-31 Nissan Motor Co Ltd Control device for diesel engine
JP2002276438A (en) * 2001-03-15 2002-09-25 Toyota Motor Corp Idling fuel supply control method and its device
US6688283B2 (en) * 2001-09-12 2004-02-10 Daimlerchrysler Corporation Engine start strategy

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