GB2501705A - Exhaust system oxygen sensor calibration procedure - Google Patents
Exhaust system oxygen sensor calibration procedure Download PDFInfo
- Publication number
- GB2501705A GB2501705A GB1207581.8A GB201207581A GB2501705A GB 2501705 A GB2501705 A GB 2501705A GB 201207581 A GB201207581 A GB 201207581A GB 2501705 A GB2501705 A GB 2501705A
- Authority
- GB
- United Kingdom
- Prior art keywords
- value
- parameter
- exhaust system
- oxygen concentration
- pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
- 239000001301 oxygen Substances 0.000 title claims abstract description 127
- 229910052760 oxygen Inorganic materials 0.000 title claims abstract description 127
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 title claims abstract description 126
- 238000000034 method Methods 0.000 title claims abstract description 62
- 238000012937 correction Methods 0.000 claims abstract description 68
- 238000002485 combustion reaction Methods 0.000 claims abstract description 41
- 239000000446 fuel Substances 0.000 claims description 124
- 238000002347 injection Methods 0.000 claims description 46
- 239000007924 injection Substances 0.000 claims description 46
- 230000006870 function Effects 0.000 claims description 30
- 238000004590 computer program Methods 0.000 claims description 11
- 230000000875 corresponding effect Effects 0.000 claims description 11
- 230000001276 controlling effect Effects 0.000 claims description 5
- 229940090044 injection Drugs 0.000 claims 3
- 239000007789 gas Substances 0.000 description 32
- 230000008901 benefit Effects 0.000 description 15
- 239000000203 mixture Substances 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 238000004891 communication Methods 0.000 description 4
- 229960003903 oxygen Drugs 0.000 description 4
- 238000003860 storage Methods 0.000 description 4
- 230000032683 aging Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- RDYMFSUJUZBWLH-UHFFFAOYSA-N endosulfan Chemical compound C12COS(=O)OCC2C2(Cl)C(Cl)=C(Cl)C1(Cl)C2(Cl)Cl RDYMFSUJUZBWLH-UHFFFAOYSA-N 0.000 description 3
- 238000011156 evaluation Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 239000002826 coolant Substances 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- 241001052209 Cylinder Species 0.000 description 1
- 208000036366 Sensation of pressure Diseases 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000013101 initial test Methods 0.000 description 1
- -1 lean NO traps Substances 0.000 description 1
- 230000014759 maintenance of location Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 150000002926 oxygen Chemical class 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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
- F02D41/14—Introducing closed-loop corrections
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
- F02D41/1448—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an exhaust gas pressure
-
- 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
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
- F02D41/1454—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an oxygen content or concentration or the air-fuel ratio
-
- 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
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
- F02D41/1454—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an oxygen content or concentration or the air-fuel ratio
- F02D41/1456—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being an oxygen content or concentration or the air-fuel ratio with sensor output signal being linear or quasi-linear with the concentration of oxygen
-
- 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
- F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
- F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
- F02D41/2425—Particular ways of programming the data
- F02D41/2429—Methods of calibrating or learning
- F02D41/2451—Methods of calibrating or learning characterised by what is learned or calibrated
- F02D41/2474—Characteristics of sensors
-
- 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
- F02D41/3005—Details not otherwise provided for
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M15/00—Testing of engines
- G01M15/04—Testing internal-combustion engines
- G01M15/10—Testing internal-combustion engines by monitoring exhaust gases or combustion flame
- G01M15/102—Testing internal-combustion engines by monitoring exhaust gases or combustion flame by monitoring exhaust gases
- G01M15/104—Testing internal-combustion engines by monitoring exhaust gases or combustion flame by monitoring exhaust gases using oxygen or lambda-sensors
-
- 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
- F02D41/12—Introducing corrections for particular operating conditions for deceleration
- F02D41/123—Introducing corrections for particular operating conditions for deceleration the fuel injection being cut-off
-
- 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
- F02D41/24—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means
- F02D41/2406—Electrical control of supply of combustible mixture or its constituents characterised by the use of digital means using essentially read only memories
- F02D41/2425—Particular ways of programming the data
- F02D41/2429—Methods of calibrating or learning
- F02D41/2441—Methods of calibrating or learning characterised by the learning conditions
- F02D41/2445—Methods of calibrating or learning characterised by the learning conditions characterised by a plurality of learning conditions or ranges
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Emergency Medicine (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Analytical Chemistry (AREA)
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
The invention provides a method of controlling an exhaust system 270 of an internal combustion engine 110, wherein the method comprises a calibratÂing procedure of an oxygen sensor 435 located in the exhaust system. The calibrating procedure comprises the steps of: measuring a plurality of values P1...Pn of a parameter indicative of a pressure in the exhaust system; measurÂing, through the oxygen sensor, a value O1...On of a parameter indicative of an oxygen concentration in the exhaust system during the measuring of each value of the pressure parameter. A correction value is calculated using each measured value of the oxygen concentration parameter and a predetermined reference value thereof; the correction value represents a deviation between the measured value of the oxygen concentration parameter and the reference value. Each calculated correcÂtion value and each corresponding measured value of the pressure parameter are used to determine a correction function CF representing the variation of the correction value over the variation of the pressure parameter.
Description
S METHOD OF CONTROLLING AN INTERNAL COMBUSTION ENGINE
TECHNICAL FIELD
The present disclosure relates to a method of controlling an exhaust system of an inter-nal combustion engine of a motor vehicle.
BACKGROUND
It is known that an internal combustion engine of a motor vehicle generally comprises an engine block defining a plurality of cylinders, each of which accommodates a reciprocat-ing piston coupled to rotate a crankshaft. Each piston cooperates with a cylinder head to define a combustion chamber, in which an air and fuel mixture is disposed and ignited, thereby producing hot expanding exhaust gases that causes the reciprocal movements of the piston.
The fuel is delivered into each combustion chambers by means of a dedicated fuel injec-tor, which is usually operated by an engine control unit (ECU) to perform a plurality of separated fuel injections per engine cycle, according to predetermined injection pattern.
The fuel quantity injected by means of each fuel injection depends mainly on the so called energizing time, namely the time interval between the opening and the closure of the fuel injector.
The exhaust gases produced by the combustion processes are directed into an exhaust system, which generally comprises an exhaust manifold for collecting the exhaust gases exiting the cylinders, an exhaust pipe for conveying the exhaust gases from the exhaust manifold to the external environment, and one or more exhaust aftertreatment devices located in the exhaust pipe to change the composition of the exhaust gases, in order to reduce the polluting emission of the internal combustion engine.
Some exhaust systems may further include an oxygen sensor, also referred as Universal Exhaust Gas Oxygen (UEGO) sensor, which is provided for measuring values of an oxy-gen concentration in the exhaust gases.
S This oxygen sensor is typically used to correct the fuel injections performed by the fuel injectors, in order to deliver the quantity of fuel requested for the internal combustion en-gine to operate properly and respect the emission level standards.
1-lowever, the values of the oxygen concentration measured by the UEGO sensor are generally affected by many factors, such as for example the exhaust gas composition, the exhaust gas temperature, the aging of the UEGO sensor, the operating temperature of the UEGO sensor, the fouling of the UEGO sensor, and particularly by the exhaust gas pressure For this reason, the values of the oxygen concentration parameter measured by the UEGO sensor are generally corrected through an open loop correction strategy, which comprises the steps of measuring a value of the pressure within the exhaust system, of using the measured pressure value to determine a correction value, and then of applying the correction value to the raw value of the oxygen concentration parameter measured by the UEGO sensor.
More particularly, the correction value is generally determined through an empirically de-termined compensation function, usually provided by the manufacturer of the UEGO sensor, which describes the variation of the correction value over the variation of the pressure in the exhaust system.
The values of the oxygen concentration parameter obtained with this conventional cor-rection strategy have an accuracy which is sufficient when these values are involved in strategy for compensating big fuel injections, such as for example main injections, but may be insufficient when these values are used in a small quantity adjustment strategy, namely a strategy for compensating small fuel injections, such as for example pilot injec-tions.
The small quantity adjustment strategy is carried out during an overrun driving made, when the internal combustion engine operates in fuel cut-off condition.
Under this condition, the small quantity adjustment strategy generally may include the steps of: -commanding a fuel injector to perform one or more fuel injections having a predeter-mined value of the energizing time, more particularly a value of the eneiizing time that nominally corresponds to a small fuel injected quantity (e.g. 1mm3); -measuring, through the UEGO sensor, a value of an oxygen concentration in the ex-haust gas that is generated by the combustion of the fuel quantity actually injected by the fuel injection; -adjusting the vaiue of the energizing time, if the measured value of the oxygen concen-tration differs from an expected value thereof; and then -repeating the preceding steps until the measured value of the oxygen concentration co-incides with the expected value.
The value of the energizing time that satisfies this last condition is finally memorized, and used afterwards to correct the fuel injections made by the fuel injector during the normal operation of the intemal combustion engine.
From the above, it follows that the reliability of this small quantity adjustment strategy is strictly dependent on the accuracy of the measured values of the oxygen concentration.
However, there are several reasons why the oxygen concentration values measured by an UEGO sensor, and corrected with the conventional correction strategy, are not always sufficiently accurate for performing a reliable small quantity adjustment strategy.
A first reason is that the compensation function provided by the manufacturer of the (JEGO sensor is empirically determined over a wide range of exhaust gas pressure val- ues, which takes into account all the possible operating conditions of the internal com-bustion engine, and not only the fuel cut-off condition of the small quantity adjustment strategy. As a consequence, the reliability of the compensation function in the reduced range of exhaust gas pressure values measurable under a fuel cut-off condition, may be affected by a great degree of approximation.
A second reason is that the compensation function provided by the manufacturer of the UEGC sensor is empirically determined taking into account only the effects of the static values of the exhaust gas pressure, disregarding the effects of the dynamic variation of the exhaust gas pressure due to the reciprocating movement of the engine pistons.
A third reason is that the compensation function provided by the manufacturer of the UEGO sensor is empirically determined using a nominal LJEGO sensor, so that it com-pletely disregards the effects of the production spread and the aging of the specific UEGO sensors that are mounted on each internal combustion engine.
In view of the above, an object of an embodiment of the present invention is that of providing a strategy for determining more accurate correction values to be applied to the measuring made by an UEGO sensor, and accordingly for determining also more reliable values of the oxygen concentration in the exhaust gases produced by an internal com-bustion engine.
Another object is that of providing an improved small quantity adjustment strategy, there-by allowing the fuel injectors to perform more accurate fuel injections also during the normal operation of the internal combustion engine.
Still another object is that of achieving these goals with a simple, rational and almost cheap solution.
SUMMARY
These and/or other objects are attained by the characteristics of the embodiments of the invention as reported in independent claims. The dependent claims recite preferred and/or especially advantageous features of the embodiments of the invention.
More particularly, an embodiment of the invention provides a method of controlling an exhaust system of an internal combustion engine, wherein the method comprises a cali- brating procedure of an oxygen sensor located in the exhaust system, wherein the cali-brating procedure comprises the steps of: -measuring a plurality of values of a parameter indicative of a pressure in the exhaust system, -measuring, through the oxygen sensor, a value of a parameter indicative of an oxygen concentration in the exhaust system during the measuring of each value of the pressure parameter, -using each measured value of the oxygen concentration parameter and a predeter-mined reference value thereof, to calculate a correction value representing a deviation between the measured value of the oxygen concentration parameter and the reference value, -using each calculated correction value and each corresponding measured value of the pressure parameter, to determine a correction function representing the variation of the correction value over the variation of the pressure parameter.
This embodiment of the invention has the advantage of generating a correction function that is customized for the specific UEGO sensor mounted in the exhaust system of the intemal combustion engine, thereby avoiding the errors that are generated by the nomi-nal correction function due to the production spread of the UEGO sensors.
According to an aspect of the invention, the measuring of the plurality of values of the pressure parameter is performed while the internal combustion engine is operating under a fuel cut-off condition.
This aspect of the invention has the advantage of generating a correction function that is specifically built up for the restricted range of pressure values measured in the exhaust system during a fuel cut-off condition. As a consequence, within this specific range of pressure values, the correction function generated with this embodiment of the invention may be more accurate than the nominal pressure curve provided by the manufacturer of the UEGO sensor.
According to another aspect of the invention, the method may further comprise an evalu- ating procedure of a parameter indicative of an oxygen concentration in the exhaust sys-tem, wherein the evaluating procedure comprises the steps of: -measuring through the oxygen sensor a raw value of the oxygen concentration parame-ter in the exhaust system, -measuring an actual value of the parameter indicative of the pressure in the exhaust system, during the measuring of the raw value of the oxygen concentration parameter, -using the correction function to determine an actual correction value corresponding to the measured actual value of the pressure parameter, -using the determined actual correction value to correct the raw value of the oxygen concentration parameter.
This embodiment of the invention takes advantage of the calibration procedure disclosed above, thereby providing a reliable evaluation of the oxygen concentration in the exhaust system.
According to another aspect of the invention, the method may further comprise a com- pensating procedure of an injection drift of a fuel injector of the internal combustion en-gine, wherein the compensating procedure comprises the steps of: -operating the fuel injector to perform a fuel injection having an energizing time value, -using the evaluating procedure to determine a value of a parameter indicative of an ox-ygen concentration in the exhaust system due to the fuel injection, -adjusting the energizing time value, if the determined value of the oxygen concentration parameter differs from an expected value thereof, -repeating the preceding steps, until the determined value of the oxygen concentration parameter is equal to the expected value.
This embodiment of the invention takes advantage of the oxygen concentration evaluat-ing procedure disclosed above, and consequently of the calibrating procedure included therein, thereby guaranteeing a more reliable and accurate compensation of the fuel in-jection drift.
According to still another aspect of the invention, the method may comprise the further steps of: -memorizing the value of the energizing time for which the measured value of the oxy-gen concentration parameter is equal to the expected value thereof, and -using the memorized energizing time value to correct subsequent fuel injections per-formed by the fuel injector.
This embodiment of the invention takes advantage of the injection drift compensating procedure disclosed above, and consequently of the oxygen concentration evaluating procedure and of the calibrating procedure included therein, thereby achieving a more effective control of the fuel injections performed by the fuel injector.
The methods according to the invention can be carried out with the help of a computer program comprising a program-code for carrying out all the steps of the methods de-scribed above, and in the form of a computer program product on which the computer program is stored. The methods can be also embodied as an electromagnetic signal, said signal being modulated to carry a sequence of data bits which represent a computer program to carry out all steps of the methods.
The computer program product may be embodied as an internal combustion engine comprising a fuel injector, an exhaust system, an oxygen sensor located in the exhaust system, an electronic control unit (ECU) connected to the fuel injector and to the oxygen sensor, a memory system connected to the electronic control unit, and the computer program stored in the memory system.
Another embodiment of the invention provides an apparatus for controlling an exhaust system of an internal combustion engine, wherein the apparatus comprises calibrating means for calibrating an oxygen sensor located in the exhaust system, wherein the cali-brating means comprise: -means for measuring a plurality of values of a parameter indicative of a pressure in the exhaust system, -means for measuring, through an oxygen sensor, a value of a parameter indicative of an oxygen concentration in the exhaust system during the measuring of each value of the pressure parameter, -means for using each measured value of the oxygen concentration parameter and a predetermined reference value thereof, to calculate a correction value representing a de- viation between the measured value of the oxygen concentration parameter and the ref-erence value, -means for using each calculated correction value and each corresponding measured value of the pressure parameter, to determine a correction function representing the var-iation of the correction value over the variation of the pressure parameter.
This embodiment of the invention has the same advantages of the method disclosed above, in particular that of providing a more reliable and accurate correction function for the oxygen sensor actually mounted on the internal combustion engine.
According to an aspect of this embodiment, the means for measuring the plurality of val-ues of the pressure parameter are configured to measure while the internal combustion engine is operated under a fuel cut-off condition.
This aspect of the invention has the advantage of generating a correction function that is specifically built up for the restricted range of pressure values measured in the exhaust system during a fuel cut-off condition.
According to another aspect of the invention, the apparatus may further comprise evalu- ating means for evaluating a parameter indicative of an oxygen concentration in the ex-haust system, wherein the evaluating means comprise: -means for measuring through the oxygen sensor a raw value of the oxygen concentra-tion parameter in the exhaust system, -means for measuring an actual value of the parameter indicative of the pressure in the exhaust system, during the measuring of the raw value of the oxygen concentration pa-rameter, -means for using the correction function to determine an actual correction value corre-sponding to the measured actual value of the pressure parameter, -means for using the determined actual correction value to correct the raw value of the oxygen concentration parameter.
This embodiment of the invention has the advantage of providing a reliable evaluation of the oxygen concentration parameter in the exhaust system.
According to another aspect of the invention, the apparatus may further comprise com- pensating means for compensating an injection drift of a fuel injector of the internal com-bustion engine, wherein the compensating means comprise: -means for operating the fuel injector to perform a fuel injection having an energizing time value, -means for using the evaluating means to determine a value of a parameter indicative of an oxygen concentration in the exhaust system due to the fuel injection -means for adjusting the energizing time value, if the determined value of the oxygen concentration parameter differs from an expected value thereof, -means for repeating the preceding steps, until the determined value of the oxygen con-centration parameter is equal to the expected value.
This embodiment of the invention has the advantage of guaranteeing a more reliable and accurate compensation of the fuel injection drift of the fuel injector.
According to still another aspect of the invention, the apparatus may further comprise: -means for memorizing the value of the energizing time for which the compensating means return that the measured value of the oxygen concentration parameter is equal to the expected value thereof, and -means for using the memorized energizing time value to correct subsequent fuel injec-tions performed by the fuel injector.
This embodiment of the invention has the advantage of achieving a more effective con-trol of the fuel injections performed by the fuel injector.
Still another embodiment of the invention provides an automotive system comprising an internal combustion engine including a fuel injector, an exhaust system, an oxygen sen-sor located in the exhaust system, and an electronic control unit (ECU) connected to the fuel injector and to the oxygen sensor, wherein the ECU is configured to perform a cali-brating procedure of the oxygen sensor by: -measuring a plurality of values of a parameter indicative of a pressure in the exhaust system, -measuring, through the oxygen sensor, a value of a parameter indicative of an oxygen concentration in the exhaust system during the measuring of each value of the pressure parameter, -using each measured value of the oxygen concentration parameter and a predeter-mined reference value thereof, to calculate a correction value representing a deviation between the measured value of the oxygen concentration parameter and the reference value, -using each calculated correction value and each corresponding measured value of the pressure parameter, to determine a correction function representing the variation of the correction value over the variation of the pressure parameter.
Also this embodiment of the invention has the same advantages of the method disclosed above, in particular that of providing a more reliable and accurate correction function for the oxygen sensor actually mounted on the internal combustion engine.
According to an aspect of this embodiment, the plurality of values of the pressure pa-rameter are measured by the electronic control unit while the internal combustion engine is operating under a fuel cut-off condition.
This aspect of the invention has the advantage of generating a correction function that is specifically built up for the restricted range of pressure values measured in the exhaust system during a fuel cut-off condition.
According to another aspect of the embodiment the electronic control unit may be further configured to perform an evaluating procedure of a parameter indicative of an oxygen concentration in the exhaust system by: -measuring through the oxygen sensor a raw value of the oxygen concentration parame-term the exhaust system, -measuring an actual value of the parameter indicative of the pressure in the exhaust system, during the measuring of the raw value of the oxygen concentration parameter, -using the correction function to determine an actual correction value corresponding to the measured actual value of the pressure parameter, -using the determined actual correction value to correct the raw value of the oxygen concentration parameter.
This embodiment of the invention has the advantage of providing a reliable evaluation of the oxygen concentration parameter in the exhaust system.
Accordig to another aspect of the embodiment, the electronic control unit may be further configured to perform a compensating procedure of an injection drift of the fuel injector by: -operating the fuel injector to perform a fuel injection having an energizing time value, -using the evaluating procedure to determine a value of a parameter indicative of an ox-ygen concentration in the exhaust system due to the fuel injection, -adjusting the energizing time value, if the determined value of the oxygen concentration parameter differs from an expected value thereof, -repeating the preceding steps, until the determined value of the oxygen concentration parameter is equal to the expected value.
This embodiment of the invention has the advantage of guaranteeing a reliable and ac-curate compensation of the fuel injection drift of the fuel injector.
According to still another aspect of the embodiment, the electronic control unit may be further configured to: -memorize the value of the energizing time for which the measured value of the oxygen concentration parameter is equal to the expected value thereof, and -use the memorized energizing time value to correct subsequent fuel injections per-formed by the fuel injector.
This embodiment of the invention has the advantage of achieving a more effective con-trol of the fuel injections performed by the fuel injector.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described, by way of example, with reference to the accompanying drawings.
Figure 1 shows an automotive system.
Figure 2 is a schematic section A-A of an internal combustion engine belonging to the automotive system of figure 1.
Figure 3 is a flowchart representing an oxygen sensor calibration method according to an embodiment of the invention.
Figure 4 is a graph representing a correction curve obtained with the calibration method represented in figure 3.
Figure 5 is a flowchart of a method of compensating a fuel injection drift of a fuel injector according to another embodiment of the invention.
Figure 6 is a flowchart of a method of operating a fuel injector according to still another embodiment of the invention.
DETAILED DESCRIPTION
Some embodiments may include an automotive system 100, as shown in figures 1 and 2, that includes an internal combustion engine (ICE) 110 of a motor vehicle 105, in this example a Diesel engine.
The internal combustion engine 110 has an engine block 120 defining at least one cylin- der 125 having a piston 140 coupled to rotate a crankshaft 145. A cylinder head 130 co-operates with the piston 140 to define a combustion chamber 150. A fuel and air mixture (not shown) is disposed in the combustion chamber 150 and ignited, resulting in hot ex- panding exhaust gases causing reciprocal movement of the piston 140. The fuel is pro-vided by at least one fuel injector 160 and the air through at least one intake port 210.
The fuel is provided at high pressure to the fuel injector 160 from a fuel rail 170 in fluid communication with a high pressure fuel pump 180 that increases the pressure of the fuel received from a fuel source 190. Each of the cylinders 125 has at least two valves 215, actuated by a camshaft 135 rotating in time with the crankshaft 145. The valves 215 selectively allow air into the combustion chamber 150 from the port 210 and alternately allow exhaust gases to exit through at least one exhaust port 220. In some examples, a cam phaser 155 may selectively vary the timing between the camshaft 135 and the crankshaft 145.
The air may be distributed to the air intake port(s) 210 through an intake manifold 200, An air intake pipe 205 may provide air Irom the ambient environment to the intake mani-fold 200. In other embodiments, a throttle body 330 may be provided to regulate the flow of air into the manifold 200. In still other embodiments, a forced air system such as a tur-bocharger 230, having a compressor 240 rotationally coupled to a turbine 250, may be provided. Rotation of the compressor 240 increases the pressure and temperature of the air in the intake pipe 205 and manifold 200. An intercooler 260 disposed in the intake pipe 205 may reduce the temperature of the air. The turbine 250 rotates by receiving ex-haust gases from an exhaust manifold 225 that directs exhaust gases from the exhaust ports 220 and through a series of vanes prior to expansion through the turbine 250. This example shows a variable geometry turbine (VGT) with a VGT actuator 290 arranged to move the vanes to alter the flow of the exhaust gases through the turbine 250. In other embodiments, the turbocharger 230 may be fixed geometry and/or include a waste gate.
The exhaust gases exit the turbine 250 and are directed into an exhaust system 270.
The exhaust system 270 may include an exhaust pipe 275 having one or more exhaust aftertreatment devices 280. The aftertreatment devices may be any device configured to change the composition of the exhaust gases. Some examples of aftertreatment devices 280 include, but are not limited to, catalytic converters (two and three way), oxidation catalysts, lean NO traps, hydrocarbon adsorbers, selective catalytic reduction (SCR) systems, and particulate filters. Other embodiments may include an exhaust gas recircu- lation (EGR) system 300 coupled between the exhaust manifold 225 and the intake man- ifold 200. The EGR system 300 may include an EGR cooler 310 to reduce the tempera-ture of the exhaust gases in the EGR system 300. An EGR valve 320 regulates a flow of exhaust gases in the EGR system 300.
The automotive system 100 may further include an electronic control unit (ECU) 450 in communication with one or more sensors and/or devices associated with the ICE 110.
The ECU 450 may receive input signals from various sensors configured to generate the signals in proportion to various physical parameters associated with the ICE 110. The sensors include, but are not limited to, a mass airflow and temperature sensor 340, a manifold pressure and temperature sensor 350, a combustion pressure sensor 360, coolant and oil temperature and level sensors 380, a fuel rail pressure sensor 400, a camshaft position sensor 410, a crankshaft position sensor 420, an exhaust temperature sensors 425, an EGR temperature sensor 440, and a position sensor 445 for an acceler-ator pedal 446. The sensors may also include an exhaust pressure sensor 430, which is located in the exhaust pipe 275 for measuring a pressure therein, and an oxygen sensor 435, usually referred as Universal Exhaust Gas Oxygen (UEGO) sensor, for measuring an oxygen concentration in the exhaust gases present in the exhaust system 270.
Furthermore, the ECU 450 may generate output signals to various control devices that are arranged to control the operation of the ICE 110, including, but not limited to, the fuel injectors 160, the throttle body 330, the EGR Valve 320, the VGT actuator 290, and the cam phaser 155. Note, dashed lines are used to indicate communication between the ECU 450 and the various sensors and devices, but some are omitted for clarity.
Tuming now to the ECU 450, this apparatus may include a digital central processing unit (CPU) in communication with a memory system 460 and an interface bus. The memory system 460 may include various storage types including optical storage, magnetic stor- age, solid state storage, and other non-volatile memory. The interface bus may be con-figured to send, receive, and modulate analog and/or digital signals to/from the various sensors and control devices. The CPU is configured to execute instructions stored as a program in the memory system 460, and send and receive signals to/from the interface bus. The program may embody the methods disclosed herein, allowing the CPU of the ECU 450 to carryout out the steps of such methods and control the ICE 110.
The ECU 450 may be configured to execute a method of calibrating the oxygen sensor 435 located in an exhaust system 270. This calibration method may be executed while the motor vehicle 105 is in overrun. The overrun is a condition in which the motor vehicle is travelling but no fuel is injected in the ICE 110 (fuel cut-off). Generally, the motor vehicle 105 is in overrun when the accelerator pedal 446 is completely released.
As shown in the flowchart of figure 3, the calibration method provides for the ECU 450 to measure (block 500), for example through the exhaust pressure sensor 430, a plurality of values P1 P,, of a parameter indicative of a pressure within the exhaust system 270, more precisely indicative of the pressure of the gas contained in the exhaust system 270.
These values P1 P of the pressure parameter are measured at different times.
Contemporaneously, the calibration method provides for the ECU 450 to measure (block 505), through the oxygen sensor 435, a plurality of values 01 O of a parameter indic-ative of an oxygen concentration in the exhaust system 270, more precisely indicative of an oxygen concentration in the gas contained in the exhaust system 270. These values 01 0,, of the oxygen concentration parameter are measured at the same times of the above mentioned values P1 P,, of the pressure parameter. In other words1 each gener-ic ith value O of the oxygen concentration parameter is measured at the same time of the correspondent ith value P1 of the pressure parameter.
Each oxygen concentration pressure parameter Q is then individually used to calculate a correspondent ith correction value C1. The correction value C is a value indicative of the deviation between the oxygen concentration pressure parameter O and a predetermined reference value °ref thereof. By way of example, the correction value C1 may be calculat-ed according to the following formula: i_fl Since the method is carried out during a fuel cut-off, the reference value O is the same for all the measured values 01 0,, of the oxygen concentration parameter, and it may be the standard value of the oxygen concentration in the air, which is about 21%.
In this way, the calibration method calculates (block 510) a plurality of correction values C1 C, individually linked to a correspondent measured value P1 P of the pressure parameter, as shown in the graph of figure 4.
The couples of correspondent values (C1, P1) are then interpolated, so as to determine a correction function CF representative of the variation of the correction value over the var-iation of the pressure parameter (block 515).
In this way, the correction function CF results accurately built up over the specific range of measured values P1 P of the pressure parameter during the fuel cut-off, and it is also representative of the performance of the specific oxygen sensor 435 that is actually mounted in the exhaust system 270.
The calibration method may be repeated many times during the oxygen sensor lifetime, in order to keep the correction function CF updated in such a way that it can take into ac-count also the oxygen sensor aging.
The most up-to-date correction function CF is memorized in the memory system 460, in order to be used by the ECU 450 for correcting the values of the oxygen concentration parameter measured made by the oxygen sensor 450 while performing other control strategy of the ICE 110.
In particular, the correction function CF may be used by the ECU 450 to perform a meth- od of compensating injection drifts of the fuel injectors 160. This injection drift compen-sating strategy may be performed while the motor vehicle 105 is in overrun, so that the ICE 110 is working in a fuel cut-off condition. In this condition, the injection drift compen- sating strategy is performed for each fuel injector 160 one at the time, while the remain-ing fuel injectors 160 are kept closed in order to not inject any fuel.
As shown in figure 5, the injection drift compensating strategy firstly provides for initializ-ing (block 600) a value ET of an energizing time. The initial value ET is determined as the value of the energizing time that would correspond to a predetermined target value of a fuel quantity to be injected by the fuel injector 160, if the fuel injector 160 were in nomi-nal condition. The fuel quantity target value may be a small value, for example 1mm3.
The initial test value ET of the energizing time, corresponding to this fuel quantity target value, may be an empirically determined calibration value, which is stored in the memory system 460 and which the ECU 450 reads therefrom.
Afterwards, the injection drift compensating strategy provides for the ECU 450 to perform a learning routine, which comprises the initial step of commanding the fuel injector 160 to perform (block 605) one or more subsequent test fuel injections (typically one test fuel injection per engine cycle), each of which by activating the fuel injector 160 for the prede-termined value ET of the energizing time.
During these engine cycles, the learning routine provides for the ECU 450 to determine (block 625) an actual value 0 of the oxygen concentration parameter, namely of the oxy-gen concentration in the exhaust gases produced by the above mentioned one or more test fuel injections.
More particularly, the actual value 0 of the oxygen concentration parameter is deter-mined through the steps of measuring, through the oxygen sensor 435, a raw value 0' of the oxygen concentration parameter (block 610), and of contemporaneously measuring an actual value P of the pressure parameter (block 615). The actual value P of the pres-sure parameter may be measured through the exhaust pressure sensor 430.
The measured actual value P of the pressure parameter is then applied as a known quantity to the correction function CF determined as explained before, in order to deter-mine a corresponding actual correction value C corresponding to this measured actual value P of the pressure parameter (block 620).
The determined actual correction value C is finally used to correct the raw value 0 of the oxygen concentration parameter, in order to determine the actual value 0 thereof. By way of example, the actual value 0 of the oxygen concentration parameter may be cal-culated according to the following formula: 0= The actual value 0 of the oxygen concentration parameter is then compared with an ex-pected value °ex thereof. The expected value °ex of the oxygen concentration parameter may be an empirically determined value. As a mailer of fact, the expected value °ex is the value of the oxygen concentration parameter that should be measured, if the oxygen sensor 435 were a nominal operating sensor.
More particularly, the actual value C of the oxygen concentration parameter is applied to a first condition block 630, which checks if the actual value 0 of the oxygen concentra-tion parameter is higher than the expected value Oex (possibly allowing a little tolerance).
If the first condition block 630 returns positive, it means the fuel injector 160 operated for the predetermined value ET of the energizing time has injected a fuel quantity lower than expected (e.g. lower than 1mm3). In this case, the compensating strategy provides for in-crementing (block 635) the energizing time value ET of a preset amount X, and then of repeating the learning routine using this incremented energizing time value.
If conversely the first condition block 630 returns negative, the actual value 0 of the oxy-gen concentration parameter is applied to a second condition block 640, which checks if the actual value 0 of the oxygen concentration parameter is lower than the expected value Qex (possibly allowing a little tolerance). If the second condition block 640 returns positive, it means that the fuel injector 160 operated for the predetermined value ET of the energizing time has injected a fuel quantity greater than expected (e.g. greater than 1mm3). In this case, the compensating strategy provides for decrementing (block 645) the predetermined energizing time value ET of a preset amount Y, and then of repeating the learning routine using this decremented energizing time value.
In other words, the energizing time value ET is adjusted and the learning routine is re-peated, until an energizing time value ETt is found for which both the condition blocks 630 and 640 return negative.
When both the condition blocks 630 and 640 return negative, it means that the actual value 0 of the oxygen concentration parameter is equal to the expected value 0X there-of (or within a little range of tolerances across 1), and that the fuel injector 160 operated with the last used value ET of the energizing time has injected exactly the expected fuel quantity (e.g. 1mm3).
The energizing time value ET that satisfies this condition is memorized (block 650) in the memory system 460 and the compensating strategy is ended.
Afterwards, the memorized value ET1 of the energizing time may be used to correct other fuel injections performed by the fuel injector 160 during the normal operation of the ICE 110.
More particularly, during the normal operation of the ICE 110, the ECU 450 may control the fuel injector 160 to perform some fuel injection using the strategy schematically illus-trated in figure 6. This strategy firstly provides for the ECU 450 to determine (block 700) a nominal value ET of the energizing time for the fuel injector 160. This nominal value ET of the energizing time is determined as the value that would correspond to a desired quantity of fuel to be injected, if the fuel injector 160 were a nominal operating fuel injec-tor. The strategy further provides for the ECU 450 to determine (block 705) a correction factor CF as a function of the memorized test value ET of the energizing time. The cor- rection factor CF is then subtracted (block 710) from the nominal value EL of the ener-gizing time, thereby obtaining a corrected value ET of the energizing time, Finally, the strategy provides for the ECU 450 to activate (block 715) the fuel injector 160 for the cor-rected value ET of the energizing time.
While at least one exemplary embodiment has been presented in the foregoing summary and detailed description, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the forgoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and in their legal equivalents.
REFERENCES
automotive system 105 motor vehicle internal combustion engine engine block cylinder cylinder head 135 camshaft piston crankshaft combustion chamber cam phaser 160 fuel injector fuel rail fuelpump fuel source intake manifold 205 air intake pipe 210 intake port 215 valves 220 exhaust port 225 exhaust manifold 230 turbocharger 240 compressor 250 turbine 260 intercooler 270 exhaust system 275 exhaust pipe 280 aftertreatmerit devices 290 VGT actuator 300 exhaust gas recirculation system 310 EGR cooler 320 EGR valve 330 throttle body 340 mass airflow and temperature sensor 350 manifold pressure and temperature sensor 360 in-cylinder pressure sensor 380 coolant and oil temperature and level sensors 400 fuel rail pressure sensor 410 camshaft position sensor 420 crankshaft position sensor 425 exhaust temperature sensor 430 exhaust pressure sensor 435 oxygen concentration sensor 440 EGR temperature sensor 445 accelerator pedal position sensor 446 accelerator pedal 450 ECU 460 memory system 500 block 505 block 510 block 515 block 600 block 605 block 610 block 615 block 620 block 625 block 630 block 635 block 640 block 645 block 650 block 700 block 705 block 710 block 715 block P1 P measured values of a pressure parameter 01 0, measured values of an oxygen concentration parameter C1 C., correction values CF correction function ET energizing time value for test injection 0 raw value of the oxygen concentration parameter P actual value of the pressure parameter C actual correction value 0 actual value of the oxygen concentration parameter °ex expected value of the oxygen concentration parameter X amount Y amount ETn nominal value of the energizing time CF correction factor ET corrected value of the energizing time
Claims (9)
- CLAIMS1. A method of controlling an exhaust system (270) of an internal combustion engine (110), wherein the method comprises a calibrating procedure of an oxygen sensor (435) located in the exhaust system (270), wherein the calibrating procedure comprises the steps of: -measuring a plurality of values (P1 P0) of a parameter indicative of a pressure in the exhaust system (270), -measuring, through the oxygen sensor (435), a value (0 0) of a parameter indica-tive of an oxygen concentration in the exhaust system (270) during the measuring of each value (P1 P) of the pressure parameter, -using each measured value (O O,) of the oxygen concentration parameter and a predetermined reference value thereof, to calculate a correction value (C1 C) repre-senting a deviation between the measured value of the oxygen concentration parameter and the reference value, -using each calculated correction value (C1 C0) and each corresponding measured value (P1 P) of the pressure parameter, to determine a correction function (CF) rep- resenting the variation of the correction value over the variation of the pressure parame-te r.
- 2. A method according to claim 1, wherein the measuring of the plurality of values (P1 P0) of the pressure parameter is performed while the internal combustion engine (110) is operating under a fuel cut-off condition.
- 3. A method according to any of the preceding claims, comprising an evaluating pro-cedure of a parameter indicative of an oxygen concentration in the exhaust system (270), wherein the evaluating procedure comprises the steps of: -measuring through the oxygen sensor (435) a raw value (C) of the oxygen concentra-tion parameter in the exhaust system (270), -measuring an actual value (P) of the parameter indicative of the pressure in the exhaust system (270), during the measuring of the raw value of the oxygen concentration param-eter, -using the correction function (CF) to determine an actual correction value (C) corre-sponding to the measured actual value (P) of the pressure parameter, -using the determined actual correction value (C) to correct the raw value of the oxygen concentratiOn parameter.
- 4. A method according to claim 3, comprising a compensating procedure of an injec-tion drift of a fuel injector (160) of the internal combustion engine (110), wherein the compensating procedure comprises the steps of: -operating the fuel injector (160) to perform a fuel injection having an energizing time 13 value (E'), -using the evaluating procedure to determine a value (0) of a parameter indicative of an oxygen concentration in the exhaust system (270) due to the fuel injection, -adjusting the energizing time value (Et), if the determined value (0) of the oxygen con-centration parameter differs from an expected value (Oex) thereof, -repeating the preceding steps, until the determined value (0) of the oxygen concentra-tion parameter is equal to the expected value (O).
- 5. A method according to claim 4, comprising the further steps of: -memorizing the value (Et) of the energizing time for which the measured value (0) of the oxygen concentration parameter is equal to the expected value (Oex) thereof, and -using the memorized energizing time value (E') to correct subsequent fuel injections performed by the fuel injector (160).
- 6-A computer program comprising a computer code suitable for performing the method according to any of the preceding claims.
- 7. A computer program product on which the computer program of claim 6 is stored.
- 8. An electromagnetic signal modulated to carry a sequence of data bits representing a computer program according to claim 6.
- 9. An internal combustion engine (110) comprising a fuel injector (160), an exhaust system (270), an oxygen sensor (435) located in the exhaust system (270), an electronic control unit (450) connected to the fuel injector (160) and to the oxygen sensor (435), a memory system (460) connected to the electronic control unit (450), and the computer program of claim 6 stored in the memory system.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1207581.8A GB2501705A (en) | 2012-04-30 | 2012-04-30 | Exhaust system oxygen sensor calibration procedure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB1207581.8A GB2501705A (en) | 2012-04-30 | 2012-04-30 | Exhaust system oxygen sensor calibration procedure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB201207581D0 GB201207581D0 (en) | 2012-06-13 |
| GB2501705A true GB2501705A (en) | 2013-11-06 |
Family
ID=46330599
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB1207581.8A Withdrawn GB2501705A (en) | 2012-04-30 | 2012-04-30 | Exhaust system oxygen sensor calibration procedure |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2501705A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140150760A1 (en) * | 2012-12-05 | 2014-06-05 | Ford Global Technologies, Llc | Methods and systems for a gas constituent sensor |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60166728A (en) * | 1984-02-08 | 1985-08-30 | Toyota Motor Corp | Electronic control device for supercharged engine |
| JPH0942066A (en) * | 1995-07-31 | 1997-02-10 | Isuzu Motors Ltd | Method and device for recirculating exhaust gas |
| FR2849112A1 (en) * | 2002-12-18 | 2004-06-25 | Renault Sa | Internal combustion engine controlling method, involves developing correction instruction for throttle and recirculation valve, injectors, supplying system, sensors, and probes as function of gaps between theoretical signal |
| WO2008071500A1 (en) * | 2006-12-13 | 2008-06-19 | Continental Automotive Gmbh | Method for calibrating a lambda sensor and internal combustion engine |
-
2012
- 2012-04-30 GB GB1207581.8A patent/GB2501705A/en not_active Withdrawn
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60166728A (en) * | 1984-02-08 | 1985-08-30 | Toyota Motor Corp | Electronic control device for supercharged engine |
| JPH0942066A (en) * | 1995-07-31 | 1997-02-10 | Isuzu Motors Ltd | Method and device for recirculating exhaust gas |
| FR2849112A1 (en) * | 2002-12-18 | 2004-06-25 | Renault Sa | Internal combustion engine controlling method, involves developing correction instruction for throttle and recirculation valve, injectors, supplying system, sensors, and probes as function of gaps between theoretical signal |
| WO2008071500A1 (en) * | 2006-12-13 | 2008-06-19 | Continental Automotive Gmbh | Method for calibrating a lambda sensor and internal combustion engine |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20140150760A1 (en) * | 2012-12-05 | 2014-06-05 | Ford Global Technologies, Llc | Methods and systems for a gas constituent sensor |
| US9382880B2 (en) * | 2012-12-05 | 2016-07-05 | Ford Global Technologies, Llc | Methods and systems for a gas constituent sensor |
Also Published As
| Publication number | Publication date |
|---|---|
| GB201207581D0 (en) | 2012-06-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11143126B2 (en) | Monitoring deviations occurring in the valve drive of an internal combustion engine, and electronic engine control units for executing such methods | |
| US9845736B2 (en) | Method of determining the timing and quantity of fuel injection to operate an internal combustion engine | |
| US8370065B2 (en) | Engine control system with algorithm for actuator control | |
| US20110106399A1 (en) | Engine control system with algorithm for actuator control | |
| US9644566B2 (en) | Control apparatus for operating a fuel injector | |
| US9404436B2 (en) | Method for operating an internal combustion engine using a corrected energizing time for fuel injections | |
| US10302036B2 (en) | Computer program for operating an internal combustion engine | |
| WO2007040904A1 (en) | Model-based controller for auto-ignition optimization in a diesel engine | |
| US7881855B2 (en) | Method for metering fuel into combustion chambers of an internal combustion engine | |
| GB2552187A (en) | A method of operating an internal combustion engine | |
| CN109209715B (en) | Method for determining a fuel quantity injected by an injector with leakage correction | |
| US10450987B2 (en) | Method of operating a fuel injector | |
| US9103294B2 (en) | Fuel drift estimation and compensation for operation of an internal combustion engine | |
| GB2498783A (en) | A method of operating an internal combustion engine to provide correction of fuel injection times and indication of injector failure | |
| US20120296555A1 (en) | Method for operating an internal combustion engine | |
| GB2501705A (en) | Exhaust system oxygen sensor calibration procedure | |
| US10487768B2 (en) | Method and system for controlling injections by fuel injectors | |
| CN106285987B (en) | Method for correcting the standard characteristic curve of a standard fuel injector of an internal combustion engine | |
| GB2500890A (en) | Method of compensating an injection timing drift in a fuel injection system | |
| GB2491110A (en) | Method of operating an internal combustion engine having crankshaft position sensor correction means | |
| US9284936B2 (en) | Method and device for controlling the exhaust gas recirculation rate for internal combustion engines during lean operation | |
| GB2533464A (en) | Method of operating a fuel injector of an internal combustion engine | |
| CN111412076A (en) | Method of operating a fuel injector | |
| GB2500207A (en) | Fuel injection method comprising correction factors for fuel rail pressure and fuel temperature | |
| GB2513296A (en) | Method of operating a compression ignition engine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |