US20060288966A1 - Control of autoignition timing in a HCCI engine - Google Patents
Control of autoignition timing in a HCCI engine Download PDFInfo
- Publication number
- US20060288966A1 US20060288966A1 US11/138,045 US13804505A US2006288966A1 US 20060288966 A1 US20060288966 A1 US 20060288966A1 US 13804505 A US13804505 A US 13804505A US 2006288966 A1 US2006288966 A1 US 2006288966A1
- Authority
- US
- United States
- Prior art keywords
- engine
- intake
- intake valve
- valve
- exhaust valve
- 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.)
- Abandoned
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
- F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
- F02D13/0203—Variable control of intake and exhaust valves
- F02D13/0207—Variable control of intake and exhaust valves changing valve lift or valve lift and timing
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B1/00—Engines characterised by fuel-air mixture compression
- F02B1/12—Engines characterised by fuel-air mixture compression with compression ignition
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
- F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
- F02D13/0203—Variable control of intake and exhaust valves
- F02D13/0215—Variable control of intake and exhaust valves changing the valve timing only
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
- F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
- F02D13/0261—Controlling the valve overlap
- F02D13/0265—Negative valve overlap for temporarily storing residual gas in the cylinder
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D13/00—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing
- F02D13/02—Controlling the engine output power by varying inlet or exhaust valve operating characteristics, e.g. timing during engine operation
- F02D13/0273—Multiple actuations of a valve within an engine cycle
-
- 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
- F02D41/3011—Controlling fuel injection according to or using specific or several modes of combustion
- F02D41/3017—Controlling fuel injection according to or using specific or several modes of combustion characterised by the mode(s) being used
- F02D41/3035—Controlling fuel injection according to or using specific or several modes of combustion characterised by the mode(s) being used a mode being the premixed charge compression-ignition mode
-
- 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
- F02D41/0002—Controlling intake air
- F02D2041/001—Controlling intake air for engines with variable valve actuation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
Definitions
- This invention relates to methods and systems for controlling autoignition timing of an internal combustion engine operated in a homogeneous-charge compression-ignition mode.
- a conventional gasoline-fueled internal combustion engine employs spark ignition where the fuel and air am premixed and a spark initiates a flame that propagates through the fuel/air mixture in the combustion chamber.
- the other common type of internal combustion engine employs compression ignition where the fuel and air are purposely kept separate until shortly before top dead center in the engine when the temperature of the air in the combustion chamber is high due to the compression. The fuel then is quickly injected into the combustion chamber as a very fine mist, which partially mixes with the air and autoignites in the combustion chamber. The timing of the fuel injection timing thus controls the autoignition timing. Diesel engines are illustrative of this type of compression ignition engine.
- HCCI Homogeneous-charge compression-ignition internal combustion engines
- An HCCI engine employs a premixed fuel/air charge to the combustion chamber as in a spark ignition engine, while the charge is ignited by compression ignition as in a diesel engine when the temperature of the air-fuel charge reaches an autoignition temperature in the combustion chamber.
- HCCI engines typically are provided with a conventional spark plug for each cylinder and relatively low compression ratios, typically close to those of spark ignition (SI) engines, to permit switching of operation of the engine from the HCCI mode at lower engine torques to the S 1 mode at higher engine torques without engine knocking.
- SI spark ignition
- Control of autoignition timing in an HCCI engine is more difficult than in a diesel engine, which controls fuel injection timing to control autoignition timing.
- the composition and temperature of the fuel-gas mixture in the combustion chamber must be controlled to control autoignition timing.
- Negative valve overlap control strategy involves trapping hot residual burned gas in the cylinder to subsequently mix with fresh air inducted into the combustion chamber. The trapped burned gas raises the temperature of the air-burned gas mixture to promote autoignition.
- FIG. 5 shows a plurality of intake and exhaust valve lift curves versus crank angle for an HCCI engine for purposes of illustrating the negative valve overlap strategy where different negative valve overlaps are shown for use at different engine torques.
- the autoignition timing of the HCCI engine tends to change. For example, at higher torque autoignition timing tends to advance, resulting in the increase in hear transfer losses, NO x emissions, and combustion noise. Therefore, the engine control system should adjust to move the autoignition timing back to the optimum crank angle. At lower engine torque, autoignition timing tends to be retarded resulting in an increase of CO emissions and lower combustion efficiency. The engine control system should adjust to move the autoignition timing back to the optimum crank angle.
- the present invention provides a method and system embodying a particular valve timing strategy to control the autoignition timing of a four stroke internal combustion engine operated in the HCCI mode at different engine operating conditions such as at different operator (driver) demanded engine torques.
- A-particular valve timing strategy varies lift timing of the intake valve relative to the exhaust valve, or vice versa, and relative to top dead center in response to a change in operator demanded engine torque, for example, to vary amount of trapped residual burned gas in the combustion chamber flowing to an intake or exhaust port and back to the combustion chamber by which the residual gas loses thermal energy and is cooled.
- valve timing strategy is used to control the temperature of the fresh air/residual burned gas mixture in the combustion chamber into which fuel is mixed and thus the autoignition timing to suit a given engine torque demand.
- the exhaust valve timing is substantially fixed before TDC over successive engine cycles to control the air-fuel ratio in the combustion chamber.
- the opening time of the intake valve is varied relative to TDC (e.g., advanced toward TDC) over successive intake cycles in a manner that changes the temperature of the fresh air/residual burned gas mixture in the combustion chamber into which the fuel is mixed and thus the autoignition timing.
- the exhaust valve timing and/or the fuel injection pulse width can be adjusted slightly to compensate for the effect of the temperature change of the mixture on the mass of the inducted fresh air in the combustion chamber.
- an initial intake valve opening event preferably is provided immediately after the exhaust valve closes and before TDC followed by a main intake valve event occurring after TDC in a manner to reduce or minimize engine pumping losses.
- the intake valve lift timing is substantially fixed after TDC over successive engine cycles to control the air-fuel ratio in the combustion chamber.
- the closing time of the exhaust valve is vaned relative to TDC (e.g., retarded toward TDC) over successive exhaust cycles in a manner that changes the temperature of the fresh air/residual burned gas mixture in the combustion chamber into which fuel is mixed and thus the autoignition timing.
- the intake valve timing and/or the fuel injection pulse width can be adjusted as needed in order to compensate for the effect of the temperature change of the mixture on the mass of the inducted fresh air in the combustion chamber.
- a first main exhaust valve opening event preferably is provided before TDC followed by a subsequent secondary exhaust valve event occurring after TDC immediately before opening of the intake valve in a manner to reduce or minimize engine pumping losses.
- FIG. 1 is a schematic view of an internal combustion engine and an electronic engine control unit for practicing an embodiment of the invention.
- FIG. 2 is diagram illustrating intake and exhaust valve lift-curves versus crank angle (where TDC is bottom dead center and TDC is top dead center) at a given engine speed and torque for an embodiment pursuant to the invention.
- FIG. 3 is diagram illustrating intake and exhaust valve lift curves versus crank angle at a given engine speed and torque for another embodiment pursuant to the invention having double intake valve events.
- FIG. 4 is diagram illustrating intake and exhaust valve lift curves versus crank angle at a given engine speed and torque for another embodiment pursuant to the invention having double exhaust valve events.
- FIG. 5 is a diagram illustrating conventional coordinated intake and exhaust valve lift curves versus crank angle (where BDC is bottom dead center and TDC is top dead center) of an HCCI engine at different engine torques to provide different negative valve overlaps wherein intake and exhaust lift curves 1 I, 1 E are employed at a given torque: curves 2 I, 2 E are employed at a different torque: and so on.
- a four cycle internal combustion engine 10 is illustrated as comprising a combustion chamber 12 formed by a conventional cylinder head 13 , cylinder 14 , and piston 15 .
- the combustion chamber 12 is expanded and contracted by the piston 15 reciprocating in the engine cylinder 14 .
- An intake port 16 and exhaust port 18 of the engine 10 communicate with the combustion chamber 12 in conventional manner.
- An intake valve 20 is provided in the intake port 16 .
- An intake passage 22 of the engine communicates with the intake port 16 . Air is aspirated from the intake passage 22 through the intake port 16 into the combustion chamber 12 when the intake valve 20 is open due to the piston descending in the cylinder.
- a throttle 23 is provided in intake passage 22 for adjusting the intake air flow rate of the engine in a spark ignition (S) mode.
- S spark ignition
- the throttle 23 is preferably fully open as shown in FIG. 1 .
- a conventional fuel injector 24 and spark plug 26 are provided on the cylinder head so as to communicate with the combustion chamber 12 .
- Fuel injected into the combustion chamber 12 by fuel injector 24 is mixed with fresh air aspirated from the intake port 16 and some fraction of residual burned gas in the SI mode of engine operation.
- fuel injected into the combustion chamber 12 is mixed with a fresh air-residual burned gas mixture having a much higher fraction of residual burned gas for subsequent compression in combustion chamber 12 by the piston 15 .
- the fuel injector 24 can be mounted in the intake port in the same manner as a port-fuel-injection engine.
- An exhaust valve 28 is provided in the exhaust port 18 . Burned gas is discharged from the exhaust port 18 through an exhaust passage 30 when the exhaust valve 28 is open during the exhaust stroke.
- Variable valve timing mechanisms 32 , 34 are provided on the engine to change the open/close timing of the intake valve 20 and exhaust valve 28 , respectively.
- the variable valve timing mechanisms 32 , 34 each can comprise a plural cam-type mechanism, a solenoid-actuated mechanism, and other valve timing mechanisms known in the art for adjusting the open/close timing of intake and exhaust valves of internal combustion engines.
- U.S. Pat. No. 6,295,964 describes a particular variable valve timing mechanism for an internal combustion engine.
- combustion chamber 12 and cylinder 14 with piston 15 therein are shown in FIG. 1 , those skilled in the art will appreciate that the engine 10 typically will include other similar combustion chambers/cylinders/pistons and associated intake valves, exhaust valves, fuel injectors, and spark plugs as shown in FIG. 1 .
- more than one intake valve 20 and more than one exhaust valve 28 can be provided for each combustion chamber 12
- the fuel injector 24 is illustrated as injecting fuel directly into cylinder 15 , the invention alternately can be practiced using fuel injection into the intake port 16 .
- An electronic control unit (ECU) 40 is provided to control the fuel injection amount and injection timing, the spark timing of the spark plug 26 , the opening of throttle 23 , the open/close timing of the intake valve 20 and exhaust valve 28 by variable valve timing mechanisms 32 , 34 .
- the ECU 40 comprises a microcomputer including a central processing unit, read-only memory, a random access memory, and a keep-alive memory, which retains information when the engine ignition key is turned-off for use when the engine is restarted, and an input/output interface.
- the ECU 40 can be embodied by an electronically programmable microprocessor, a microcontroller, an application-specific integrated circuit, or a like device to provide a predetermined engine control logic.
- the ECU 40 receives a plurality of signals from the engine 10 via the input/output interface.
- signals can include, but are not limited to signals from an air flow meter 42 which detects intake air flow rate in the intake passage 22 , a crank angle sensor 44 which detects crank angle of the engine 10 , an accelerator pedal depression sensor 45 which detects the amount of depression of the accelerator pedal, and a starter switch 46 which detects star-up of the engine 10 .
- the ECU 40 processes these signals received from the engine sensors and generates corresponding signals, such as a fuel injector pulse waveform signal that is transmitted to each fuel injector 24 of each cylinder 15 on a signal line to control the amount and timing of fuel delivered by each fuel injector 24 to combustion chamber 12 .
- ECU 40 provides corresponding signals to control the spark timing of each spark plug 26 , the opening of throttle 23 , and the open/dose timing of each intake valve 20 and exhaust valve 28 by each variable valve timing mechanisms 32 , 34 .
- the ECU 40 includes a combustion pattern selecting section SO implemented by a software program or programs for selecting a particular combustion mode; namely, a spark ignition mode 52 or a HCCI (compression autoignition) mode 54 , depending on engine operating conditions.
- ECU 40 can select a combustion mode based on an engine speed signal from crank angle sensor 44 and on an accelerator pedal position (indicative of a operator demand for engine torque) signal from accelerator pedal depression sensor 45 .
- ECU 40 typically selects the compression autoignition engine operating mode 54 in a predetermined engine operating region characterized by relatively low engine speed and low to medium engine torque, and selects the spark ignition mode in a very low engine torque region and in a region of high engine speed and/or high engine torque.
- ECU 40 can deactivate the spark plug 26 or alternatively continue sparking of the spark plug 26 .
- the present invention provides a method and system using a particular valve lift timing strategy to control the autoignition timing and the air-fuel ratio during engine operation in the HCCI mode 54 .
- a particular valve timing strategy pursuant to the present invention controls lift timing of one of the intake valve relative to the exhaust valve, or vice versa, and relative to top dead center to control autoignition timing at a given fixed engine speed and operator demanded engine torque.
- the air-fuel ratio also is controlled at the given fixed engine speed and torque.
- the piston 15 generates maximum compression of gases in combustion chamber 12 at TDC, the top of its stroke. Before TDC, the piston 15 moves toward combustion chamber 12 , and, after TDC, the piston 15 is moving away from the combustion chamber 12 .
- FIG. 2 shows an illustrative embodiment of the present invention where the air-fuel ratio is controlled by controlling the mass of trapped residual burned gas in the combustion chamber 12 that mixes with inducted fresh air at the time before the compression stroke of engine 10 when the engine is operated at a fixed geometric compression ratio (e.g., in the range of 10:1 to 15:1).
- the exhaust valve lift (represented by curve EV) from its opening time EVO to its dosing time EVC is plotted versus crank angle of the engine 10 .
- the exhaust valve opening and closing times under fixed operating conditions of engine speed and torque are substantially fixed or constant relative to TDC for each exhaust stroke.
- substantially fixed fresh air mass means that there is at most a minor change in the mass of fresh air inducted into the combustion chamber 12 as a result of the temperature change of the burned gas with which the air is mixed in the combustion chamber 12 as described below. This minor change in fresh air mass can be accommodated as also described below.
- FIG. 2 illustrates varying (e.g., advancing) intake valve opening (IVO) of the intake valve 20 after the exhaust valve 28 closes as indicated by valve lift curves 1 , 2 , 3 , 4 , 5 , 6 over successive intake events.
- Such varying (e.g., advancement) of intake valve opening time gradually changes (e.g., reduces) the temperature of the fresh air-residual burned gas mixture into which fuel is mixed in the combustion chamber 12 and thus the autoignition timing before compression.
- the autoignition timing can be changed in response to changes in operator demanded engine torque using such valve timing.
- intake valve lift curves IV, numbered 1 through 6 illustrate intake valve lifts from IVO to intake valve closing IVC time of this embodiment of the invention.
- Curve EV together with curve 0 represent a negative valve overlap condition where none of the trapped residual burned gas flows out of the combustion chamber 12 such that the air/residual burned gas mixture will have the highest mixture temperature at a time before the compression.
- varying (e.g., advancing) of the time of opening of the intake valve 20 as indicated by valve lift curves 1 , 2 , 3 , 4 , 3 , 6 over successive intake events gradually increases the intake time period so as to permit more and more trapped residual burned gas to be pushed out or from the combustion chamber 12 into the intake port 16 after the exhaust valve 28 doses and then to flow back to the combustion chamber when the intake valve opens and the piston descends. That is, a greater and greater portion of the original hot trapped residual burned gas is caused to flow (by higher cylinder pressure generated by compression in the exhaust stroke after the exhaust valve doses) into the intake port 16 as permitted by advanced opening of intake valve 20 and then dawn by the intake stroke from the intake port 16 back into the combustion chamber 12 .
- Autoignition timing thereby can be controllably changed by gradually changing the intake valve opening time over successive engine cycles (one engine cycle equals four strokes or two revolutions) relative to exhaust valve timing in response to changes in operator demanded engine torque.
- autoignition timing is controlled to occur near TDC such as, for example, the time of 50% completion of combustion occurs within a range of 5 to 10 degrees after TDC.
- ECU 40 slightly adjusting the exhaust valve closing time and/or the fuel injection pulse width during the period that the intake valve opening timing is being changed as may be needed in order to compensate for this effect of temperature change of the residual burned gas mixture on the mass of the fresh air inducted into the combustion chamber 12 .
- ECU 40 can move the exhaust valve closing time closer to TDC during the period when the intake valve opening timing is changed to increase the amount of hot trapped residual burned gas exhausted from the combustion chamber 12 and thereby increase the mass of inducted fresh air.
- the air-fuel ratio in combustion chamber 12 can be controlled to the stoichiometric proportion by ECU 40 determining engine torque and controlling the exhaust valve opening time and closing time as described above in response to the determined engine torque.
- the autoignition timing is adjusted by ECU 40 by gradually changing the intake valve opening time as illustrated, for example, in FIG. 2 by curves 1 through 6 over successive intake events.
- FIG. 3 illustrates another similar valve timing strategy that minimizes or eliminates engine pumping losses while controlling autoignition timing and air-fuel ratio.
- the valve timing strategy of FIG. 3 is similar to that of FIG. 2 with, however, the inclusion of an additional initial intake event IVZ before TDC
- the air-fuel ratio in combustion chamber 12 can be controlled to the stoichiometric proportion by ECU 40 determining engine torque and controlling the exhaust valve timing as described above in response to the demanded engine torque.
- Control of autoignition is achieved by advancing the intake valve opening time IVO as illustrated by curves 1 , 2 , 3 in FIG. 3 relative to TDC.
- the additional intake event IVZ is provided immediately after the exhaust valve 28 doses in the exhaust stroke as shown in FIG.
- the intake valve closing time IVC of the intake event IV 2 occurring before TDC is varied depending on the amount of advancement of the intake opening time of main intake event IV occurring after TDC That is, curve 1 ′ of the additional intake event would be employed when curve 1 represents the main intake event occurring after TDC curve 2 ′ of the additional intake event would be employed when curve 2 represents the main intake event occurring after TDC, and so on.
- Initial intake event IVZ (curve 1 ′, 2 , or 37 to TDC and the crank angle from TDC to the beginning of the subsequent main intake event (curve 1 , 2 , or 3 ) should be essentially equal to minimize engine pumping losses.
- the fuel injection timing is controlled by ECU 40 to occur typically after TDC since after TDC, the gases flow into the combustion chamber due to the downward movement of the piston.
- the fuel injection timing as controlled by ECU 40 can play a role in control of the mixture temperature, hence the autoignition timing, due to the charge cooling effect of fuel evaporation.
- later fuel injection results in lower mixture temperature before compression. That is, the charge before fuel injection (i.e., without charge cooling by fuel evaporation) is hotter, increasing heat transfer from the hot burned gas to the port walls.
- the fuel injection timing is constrained by the requirement of fuel-air mixing. Fuel droplets need time to vaporize and mix with the air.
- FIG. 4 illustrates another embodiment of the invention where the intake valve opening time IVO is controlled in a manner to control the air-fuel ratio in combustion chamber 12 and the closing time EVC of the exhaust valve 28 is varied relative to TDC (e.g., retarded toward TDC) over successive exhaust cycles in a manner that changes the temperature of the air/residual burned gas mixture into which fuel is mixed in the combustion chamber 12 and thus the autoignition timing.
- TDC e.g., retarded toward TDC
- FIG. 4 illustrates an embodiment of the present invention where the intake air mass is controlled by the intake valve opening time and dosing time so long as in-cylinder pressure at the time of intake valve opening is fixed.
- the intake valve opening and closing times IVO, IVC under fixed operating conditions of engine speed and torque are substantially fixed or constant relative to TDC for each intake stroke.
- the air-fuel ratio in combustion chamber 12 can be controlled to the stoichiometric proportion by ECU 40 determining engine torque and controlling the intake valve opening time in response to the determined engine torque.
- the exhaust valve lift timing is used to control the temperature of the fresh air-residual burned gas mixture in the combustion chamber 12 and thus the autoignition temperature before compression.
- the exhaust valve dosing times are retarded over successive exhaust strokes relative to TDC as represented by curves 1 , 2 , 3 of the initial exhaust event EV of FIG.
- the fuel injection timing is controlled by ECU 40 typically to occur after TDC since after TDC, the gases flow into the combustion chamber due to the downward movement of the piston. Therefore, the injected fuel after TDC will not flow out of the combustion chamber to the exhaust port despite the exhaust port being open.
- the injection timing can be adjusted by ECU 40 to affect the mixture temperature as described above for incylinder (direct) fuel injection.
- ECU 40 slightly adjusting the intake valve opening time and for the fuel injection pulse width during the period when the exhaust valve dosing timing is changed as may be needed in order to compensate for this effect of temperature change of the burned gas mixture on the mass of the fresh air inducted into the combustion chamber 12 .
- ECU 40 can move the intake valve opening time doser to TDC during the period of changing of the exhaust valve closing timing to increase the mass of fresh air inducted into the combustion chamber 12 .
- the additional exhaust event EV 2 is provided immediately after the exhaust valve 28 doses in the exhaust stroke and after TDC as shown in FIG. 4 to allow some residual burned gases to be drawn from the exhaust part 18 by piston motion.
- the exhaust valve opening time EVO of the second exhaust event IV 2 occurring after TDC is varied depending on the amount of advancement of the exhaust valve dosing time EVC of main intake event EV occurring before TDC. That is, curve 1 ′ of the additional exhaust event would be used when curve 1 represents the main intake event occurring after TDC, curve 2 ′ of the additional intake event would be used when curve 2 represents the main intake event occurring after TDC, and so on. As is apparent from FIG.
- crank angle from the end of the initial main exhaust event F (curves 1 , 2 , 3 ) to TDC and the crank angle from TDC to the beginning of the subsequent exhaust event EV 2 (curves 1 ′, 2 ′, 3 ′) should be essentially equal to minimize engine pumping losses.
- the air-fuel ratio in combustion chamber 12 can be controlled to the stoichiometric proportion by ECU 40 determining engine torque and controlling the intake valve open/close timing as described above in response to the determined engine torque.
- the autoignition timing is adjusted by ECU 40 by changing the exhaust valve closing timing as illustrated, for example, in FIG. 4 by curves 1 through 3 over successive exhaust events.
- FIG. 1 for controlling the intake valve 20 and the exhaust valve 28
- more than one intake valve e.g., two intake valves
- more than one exhaust valve e.g.. two exhaust valves
- the open/close timing of the intake valves or the-exhaust valves of a cylinder can be controlled either in unison or differently.
- FIG. 3 shows two intake events per cycle.
- the two intake valves can open and close differently such that the initial intake event IV 2 is realized by one intake valve and the main intake event IV is realized by the other intake valve.
- the two exhaust valves can be controlled to open and close differently when there are two exhaust events as shown in FIG. 4 such that the main exhaust EV is realized by one exhaust valve and the subsequent exhaust event EVZ is realized by the other exhaust valve.
Abstract
Method and system embody a valve timing strategy to control the autoignition timing of a four stroke internal combustion engine (10) operated in an HCCI mode at different engine operating conditions such as different engine speed and torque. A particular valve timing strategy varies lift timing of the intake valve (20) relative to the exhaust valve (28), or vice versa, and relative to top dead center in response to a change in engine torque, for example, to vary amount of trapped residual burned gas in the combustion chamber (12) flowing to an intake or exhaust port (16,18) and back to the combustion chamber during which the residual gas is cooled. Control of the flow of residual gas between the combustion chamber and intake or exhaust port and thus its temperature by the valve timing strategy, in turn, is used to control the temperature of the fresh air/residual gas/fuel mixture in the combustion chamber (12) and thus autoignition timing in response to a change in engine torque.
Description
- 1. Field of the Invention
- This invention relates to methods and systems for controlling autoignition timing of an internal combustion engine operated in a homogeneous-charge compression-ignition mode.
- 2. Background Information
- A conventional gasoline-fueled internal combustion engine employs spark ignition where the fuel and air am premixed and a spark initiates a flame that propagates through the fuel/air mixture in the combustion chamber. The other common type of internal combustion engine employs compression ignition where the fuel and air are purposely kept separate until shortly before top dead center in the engine when the temperature of the air in the combustion chamber is high due to the compression. The fuel then is quickly injected into the combustion chamber as a very fine mist, which partially mixes with the air and autoignites in the combustion chamber. The timing of the fuel injection timing thus controls the autoignition timing. Diesel engines are illustrative of this type of compression ignition engine.
- Homogeneous-charge compression-ignition (HCCI) internal combustion engines are known and offer the potential to reduce fuel consumption and NOx emissions. An HCCI engine employs a premixed fuel/air charge to the combustion chamber as in a spark ignition engine, while the charge is ignited by compression ignition as in a diesel engine when the temperature of the air-fuel charge reaches an autoignition temperature in the combustion chamber. HCCI engines typically are provided with a conventional spark plug for each cylinder and relatively low compression ratios, typically close to those of spark ignition (SI) engines, to permit switching of operation of the engine from the HCCI mode at lower engine torques to the S1 mode at higher engine torques without engine knocking.
- Control of autoignition timing in an HCCI engine is more difficult than in a diesel engine, which controls fuel injection timing to control autoignition timing. In an HCCI engine, the composition and temperature of the fuel-gas mixture in the combustion chamber must be controlled to control autoignition timing.
- It has been proposed to control HCCI autoignition timing using what has been called a negative valve overlap strategy that provides internal exhaust gas recirculation in the combustion chamber. Negative valve overlap control strategy involves trapping hot residual burned gas in the cylinder to subsequently mix with fresh air inducted into the combustion chamber. The trapped burned gas raises the temperature of the air-burned gas mixture to promote autoignition. Autoignition timing (delay) is represented by the equation: t=A exp(E/RT), where t is the time it takes for the mixture in the combustion chamber to autoignite, often called the ignition delay, A is an empirical constant, E is an activation energy and is a function of the composition of the mixture, such as type of fuel, fuel/air mixture amount of residuals, etc., and R is the universal gas constant. Because the equation expresses an exponential relationship, it is evident that temperature of the mixture plays a key role in determining if and importantly when autoignition will occur.
- Pursuant to negative valve overlap control strategy, the exhaust valve doses before top dead center (TDC) and the intake valve opens after TDC such that both valves are closed at TDC of the exhaust stroke. Such strategy controls trapping of hot residual burned gas in the combustion chamber to, in turn control the autoignition timing.
FIG. 5 shows a plurality of intake and exhaust valve lift curves versus crank angle for an HCCI engine for purposes of illustrating the negative valve overlap strategy where different negative valve overlaps are shown for use at different engine torques. In particular, for different engine torques, different pairs of intake and exhaust valve lift curves (e.g.,curves 1I, 1E; 2I, 2E; 3I, 3E: and so on) are employed in coordination with one another to provide the desired negative overlap for a particular engine torque. That is, intake and exhaustvalve lift curves 1I, 1E would be used in coordination for a particular engine torque, different intake and exhaust valve lift curves 2I. 2E would be used in coordination for a different particular engine torque, and so on. The negative valve overlap control strategy is described by Willard et al. in “The knocking syndrome—its cure and its potential”. SAE 982483, 1998. - When engine speed or torque changes, the autoignition timing of the HCCI engine tends to change. For example, at higher torque autoignition timing tends to advance, resulting in the increase in hear transfer losses, NOx emissions, and combustion noise. Therefore, the engine control system should adjust to move the autoignition timing back to the optimum crank angle. At lower engine torque, autoignition timing tends to be retarded resulting in an increase of CO emissions and lower combustion efficiency. The engine control system should adjust to move the autoignition timing back to the optimum crank angle.
- Moreover, it is desirable to operate the engine with a stoichiometric air-fuel mixture and with a conventional three-way catalyst for after-treatment of exhaust gases. Control of the mass of trapped hot residual burned gas in the cylinder can provide control of autoignition timing during HCCI engine operation. There is a need to also control air-fuel ratio to provide a stoichiometric mixture for engine operation over a wide range of climate and weather conditions without altering the autoignition timing.
- However, use of negative valve overlap as a single control variable in HCCI engine control strategy to control both the autoignition timing and the air-fuel ratio at different operating conditions is problematic in that use of a single negative valve overlap variable in the control strategy offers insufficient degrees of freedom to control the air-fuel ratio, in-cylinder gas temperature, and residual fraction of burned gas in the in-cylinder gas in a manner to provide favorable values for all of these parameters at different operating conditions.
- The present invention provides a method and system embodying a particular valve timing strategy to control the autoignition timing of a four stroke internal combustion engine operated in the HCCI mode at different engine operating conditions such as at different operator (driver) demanded engine torques. A-particular valve timing strategy varies lift timing of the intake valve relative to the exhaust valve, or vice versa, and relative to top dead center in response to a change in operator demanded engine torque, for example, to vary amount of trapped residual burned gas in the combustion chamber flowing to an intake or exhaust port and back to the combustion chamber by which the residual gas loses thermal energy and is cooled. Such control of the flow of residual burned gas between the combustion chamber and intake or exhaust port and thus its temperature by the valve timing strategy is used to control the temperature of the fresh air/residual burned gas mixture in the combustion chamber into which fuel is mixed and thus the autoignition timing to suit a given engine torque demand.
- In an illustrative embodiment of the invention, the exhaust valve timing is substantially fixed before TDC over successive engine cycles to control the air-fuel ratio in the combustion chamber. The opening time of the intake valve is varied relative to TDC (e.g., advanced toward TDC) over successive intake cycles in a manner that changes the temperature of the fresh air/residual burned gas mixture in the combustion chamber into which the fuel is mixed and thus the autoignition timing. The exhaust valve timing and/or the fuel injection pulse width can be adjusted slightly to compensate for the effect of the temperature change of the mixture on the mass of the inducted fresh air in the combustion chamber. Further, for each intake event, an initial intake valve opening event preferably is provided immediately after the exhaust valve closes and before TDC followed by a main intake valve event occurring after TDC in a manner to reduce or minimize engine pumping losses.
- In another illustrative embodiment of the invention, the intake valve lift timing is substantially fixed after TDC over successive engine cycles to control the air-fuel ratio in the combustion chamber. The closing time of the exhaust valve is vaned relative to TDC (e.g., retarded toward TDC) over successive exhaust cycles in a manner that changes the temperature of the fresh air/residual burned gas mixture in the combustion chamber into which fuel is mixed and thus the autoignition timing. The intake valve timing and/or the fuel injection pulse width can be adjusted as needed in order to compensate for the effect of the temperature change of the mixture on the mass of the inducted fresh air in the combustion chamber. For each exhaust event, a first main exhaust valve opening event preferably is provided before TDC followed by a subsequent secondary exhaust valve event occurring after TDC immediately before opening of the intake valve in a manner to reduce or minimize engine pumping losses.
- The above advantages of the present invention will become more readily apparent from the following description taken with the following drawings.
-
FIG. 1 is a schematic view of an internal combustion engine and an electronic engine control unit for practicing an embodiment of the invention. -
FIG. 2 is diagram illustrating intake and exhaust valve lift-curves versus crank angle (where TDC is bottom dead center and TDC is top dead center) at a given engine speed and torque for an embodiment pursuant to the invention. -
FIG. 3 is diagram illustrating intake and exhaust valve lift curves versus crank angle at a given engine speed and torque for another embodiment pursuant to the invention having double intake valve events. -
FIG. 4 is diagram illustrating intake and exhaust valve lift curves versus crank angle at a given engine speed and torque for another embodiment pursuant to the invention having double exhaust valve events. -
FIG. 5 is a diagram illustrating conventional coordinated intake and exhaust valve lift curves versus crank angle (where BDC is bottom dead center and TDC is top dead center) of an HCCI engine at different engine torques to provide different negative valve overlaps wherein intake andexhaust lift curves 1I, 1E are employed at a given torque:curves 2I, 2E are employed at a different torque: and so on. - Referring to
FIG. 1 , a four cycleinternal combustion engine 10 is illustrated as comprising acombustion chamber 12 formed by aconventional cylinder head 13,cylinder 14, andpiston 15. Thecombustion chamber 12 is expanded and contracted by thepiston 15 reciprocating in theengine cylinder 14. Anintake port 16 andexhaust port 18 of theengine 10 communicate with thecombustion chamber 12 in conventional manner. Anintake valve 20 is provided in theintake port 16. Anintake passage 22 of the engine communicates with theintake port 16. Air is aspirated from theintake passage 22 through theintake port 16 into thecombustion chamber 12 when theintake valve 20 is open due to the piston descending in the cylinder. Athrottle 23 is provided inintake passage 22 for adjusting the intake air flow rate of the engine in a spark ignition (S) mode. In HCCI mode, thethrottle 23 is preferably fully open as shown inFIG. 1 . Aconventional fuel injector 24 andspark plug 26 are provided on the cylinder head so as to communicate with thecombustion chamber 12. Fuel injected into thecombustion chamber 12 byfuel injector 24 is mixed with fresh air aspirated from theintake port 16 and some fraction of residual burned gas in the SI mode of engine operation. In the HCCI mode, fuel injected into thecombustion chamber 12 is mixed with a fresh air-residual burned gas mixture having a much higher fraction of residual burned gas for subsequent compression incombustion chamber 12 by thepiston 15. Alternately, thefuel injector 24 can be mounted in the intake port in the same manner as a port-fuel-injection engine. - An
exhaust valve 28 is provided in theexhaust port 18. Burned gas is discharged from theexhaust port 18 through anexhaust passage 30 when theexhaust valve 28 is open during the exhaust stroke. - Variable
valve timing mechanisms intake valve 20 andexhaust valve 28, respectively. The variablevalve timing mechanisms - Although only one
combustion chamber 12 andcylinder 14 withpiston 15 therein are shown inFIG. 1 , those skilled in the art will appreciate that theengine 10 typically will include other similar combustion chambers/cylinders/pistons and associated intake valves, exhaust valves, fuel injectors, and spark plugs as shown inFIG. 1 . Further, more than oneintake valve 20 and more than oneexhaust valve 28 can be provided for eachcombustion chamber 12, in addition, although thefuel injector 24 is illustrated as injecting fuel directly intocylinder 15, the invention alternately can be practiced using fuel injection into theintake port 16. - An electronic control unit (ECU) 40 is provided to control the fuel injection amount and injection timing, the spark timing of the
spark plug 26, the opening ofthrottle 23, the open/close timing of theintake valve 20 andexhaust valve 28 by variablevalve timing mechanisms ECU 40 comprises a microcomputer including a central processing unit, read-only memory, a random access memory, and a keep-alive memory, which retains information when the engine ignition key is turned-off for use when the engine is restarted, and an input/output interface. TheECU 40 can be embodied by an electronically programmable microprocessor, a microcontroller, an application-specific integrated circuit, or a like device to provide a predetermined engine control logic. - The
ECU 40 receives a plurality of signals from theengine 10 via the input/output interface. Such signals can include, but are not limited to signals from anair flow meter 42 which detects intake air flow rate in theintake passage 22, acrank angle sensor 44 which detects crank angle of theengine 10, an acceleratorpedal depression sensor 45 which detects the amount of depression of the accelerator pedal, and astarter switch 46 which detects star-up of theengine 10. - The
ECU 40 processes these signals received from the engine sensors and generates corresponding signals, such as a fuel injector pulse waveform signal that is transmitted to eachfuel injector 24 of eachcylinder 15 on a signal line to control the amount and timing of fuel delivered by eachfuel injector 24 tocombustion chamber 12.ECU 40 provides corresponding signals to control the spark timing of eachspark plug 26, the opening ofthrottle 23, and the open/dose timing of eachintake valve 20 andexhaust valve 28 by each variablevalve timing mechanisms - Referring to
FIG. 1 , theECU 40 includes a combustion pattern selecting section SO implemented by a software program or programs for selecting a particular combustion mode; namely, aspark ignition mode 52 or a HCCI (compression autoignition)mode 54, depending on engine operating conditions. For example,ECU 40 can select a combustion mode based on an engine speed signal fromcrank angle sensor 44 and on an accelerator pedal position (indicative of a operator demand for engine torque) signal from acceleratorpedal depression sensor 45.ECU 40 typically selects the compression autoignitionengine operating mode 54 in a predetermined engine operating region characterized by relatively low engine speed and low to medium engine torque, and selects the spark ignition mode in a very low engine torque region and in a region of high engine speed and/or high engine torque. When thecompression autoignition mode 54 is selected.ECU 40 can deactivate thespark plug 26 or alternatively continue sparking of thespark plug 26. - The present invention provides a method and system using a particular valve lift timing strategy to control the autoignition timing and the air-fuel ratio during engine operation in the
HCCI mode 54. A particular valve timing strategy pursuant to the present invention controls lift timing of one of the intake valve relative to the exhaust valve, or vice versa, and relative to top dead center to control autoignition timing at a given fixed engine speed and operator demanded engine torque. The air-fuel ratio also is controlled at the given fixed engine speed and torque. As is known, thepiston 15 generates maximum compression of gases incombustion chamber 12 at TDC, the top of its stroke. Before TDC, thepiston 15 moves towardcombustion chamber 12, and, after TDC, thepiston 15 is moving away from thecombustion chamber 12. -
FIG. 2 shows an illustrative embodiment of the present invention where the air-fuel ratio is controlled by controlling the mass of trapped residual burned gas in thecombustion chamber 12 that mixes with inducted fresh air at the time before the compression stroke ofengine 10 when the engine is operated at a fixed geometric compression ratio (e.g., in the range of 10:1 to 15:1). InFIG. 2 , the exhaust valve lift (represented by curve EV) from its opening time EVO to its dosing time EVC is plotted versus crank angle of theengine 10. As shown, the exhaust valve opening and closing times under fixed operating conditions of engine speed and torque are substantially fixed or constant relative to TDC for each exhaust stroke. With fixed exhaust valve opening time and closing time, the amount of residual burned gas that does not flow into theexhaust port 18 is, in turn, fixed regardless of the intake valve timing. Thus, at a fixed intake (in-cylinder) pressure, the mass of fresh intake air inducted into thecombustion chamber 12 is substantially fixed such that the air-fuel ratio can be controlled. At a given engine speed, the exhaust valve timing is used to control air-fuel ratio incombustion chamber 12, which in turn provides the operator (driver) demanded engine torque. As used above, substantially fixed fresh air mass means that there is at most a minor change in the mass of fresh air inducted into thecombustion chamber 12 as a result of the temperature change of the burned gas with which the air is mixed in thecombustion chamber 12 as described below. This minor change in fresh air mass can be accommodated as also described below. -
FIG. 2 illustrates varying (e.g., advancing) intake valve opening (IVO) of theintake valve 20 after theexhaust valve 28 closes as indicated by valve lift curves 1, 2, 3, 4, 5, 6 over successive intake events. Such varying (e.g., advancement) of intake valve opening time gradually changes (e.g., reduces) the temperature of the fresh air-residual burned gas mixture into which fuel is mixed in thecombustion chamber 12 and thus the autoignition timing before compression. The autoignition timing can be changed in response to changes in operator demanded engine torque using such valve timing. intake valve lift curves IV, numbered 1 through 6, illustrate intake valve lifts from IVO to intake valve closing IVC time of this embodiment of the invention. Curve EV together withcurve 0 represent a negative valve overlap condition where none of the trapped residual burned gas flows out of thecombustion chamber 12 such that the air/residual burned gas mixture will have the highest mixture temperature at a time before the compression. - In effect, varying (e.g., advancing) of the time of opening of the
intake valve 20 as indicated by valve lift curves 1, 2, 3, 4, 3, 6 over successive intake events gradually increases the intake time period so as to permit more and more trapped residual burned gas to be pushed out or from thecombustion chamber 12 into theintake port 16 after theexhaust valve 28 doses and then to flow back to the combustion chamber when the intake valve opens and the piston descends. That is, a greater and greater portion of the original hot trapped residual burned gas is caused to flow (by higher cylinder pressure generated by compression in the exhaust stroke after the exhaust valve doses) into theintake port 16 as permitted by advanced opening ofintake valve 20 and then dawn by the intake stroke from theintake port 16 back into thecombustion chamber 12. Transmission of the residual burned gas between the combustion chamber and the intake port in this manner reduces thermal energy of the residual burned gas by heat transfer to adjacent intake port walls without reducing the mass of the residual-burned gas in thecombustion chamber 12. Such transmission is effective to control the mass ratio of original hot trapped residual burned gas to the cooler recycled burned gas so as to gradually decrease (or increase) the temperature of the fresh air/residual burned gas mixture into which fuel is mixed in the combustion chamber before compression. Autoignition timing thereby can be controllably changed by gradually changing the intake valve opening time over successive engine cycles (one engine cycle equals four strokes or two revolutions) relative to exhaust valve timing in response to changes in operator demanded engine torque. Typically, autoignition timing is controlled to occur near TDC such as, for example, the time of 50% completion of combustion occurs within a range of 5 to 10 degrees after TDC. - When the temperature of the residual burned gas in the
combustion chamber 12 is changed, the mass of the fresh intake air inducted into the combustion chamber and mixed with the residual burned gas mixture will also be accordingly changed by a minor amount despite the intake (incylinder) pressure and geometric compression ratio of the engine remaining unchanged. The invention envisionsECU 40 slightly adjusting the exhaust valve closing time and/or the fuel injection pulse width during the period that the intake valve opening timing is being changed as may be needed in order to compensate for this effect of temperature change of the residual burned gas mixture on the mass of the fresh air inducted into thecombustion chamber 12. For example,ECU 40 can move the exhaust valve closing time closer to TDC during the period when the intake valve opening timing is changed to increase the amount of hot trapped residual burned gas exhausted from thecombustion chamber 12 and thereby increase the mass of inducted fresh air. - According to this embodiment of the invention, at any fixed engine speed, the air-fuel ratio in
combustion chamber 12 can be controlled to the stoichiometric proportion byECU 40 determining engine torque and controlling the exhaust valve opening time and closing time as described above in response to the determined engine torque. The autoignition timing is adjusted byECU 40 by gradually changing the intake valve opening time as illustrated, for example, inFIG. 2 bycurves 1 through 6 over successive intake events. -
FIG. 3 illustrates another similar valve timing strategy that minimizes or eliminates engine pumping losses while controlling autoignition timing and air-fuel ratio. - The valve timing strategy of
FIG. 3 is similar to that ofFIG. 2 with, however, the inclusion of an additional initial intake event IVZ before TDC Similar toFIG. 2 , at a fixed engine speed, the air-fuel ratio incombustion chamber 12 can be controlled to the stoichiometric proportion byECU 40 determining engine torque and controlling the exhaust valve timing as described above in response to the demanded engine torque. Control of autoignition is achieved by advancing the intake valve opening time IVO as illustrated bycurves FIG. 3 relative to TDC. To avoid engine pumping losses, the additional intake event IVZ is provided immediately after theexhaust valve 28 doses in the exhaust stroke as shown inFIG. 3 to allow some residual burned gas to be pushed into theintake port 16 due to continued upward movement of thepiston 14 in the exhaust stroke. The intake valve closing time IVC of the intake event IV2 occurring before TDC is varied depending on the amount of advancement of the intake opening time of main intake event IV occurring after TDC That is,curve 1′ of the additional intake event would be employed whencurve 1 represents the main intake event occurring afterTDC curve 2′ of the additional intake event would be employed whencurve 2 represents the main intake event occurring after TDC, and so on. As is apparent fromFIG. 3 , the crank angle from the end of the additional. Initial intake event IVZ (curve 1′, 2, or 37 to TDC and the crank angle from TDC to the beginning of the subsequent main intake event (curve - In the embodiments of
FIGS. 2 and 3 , the fuel injection timing is controlled byECU 40 to occur typically after TDC since after TDC, the gases flow into the combustion chamber due to the downward movement of the piston. If an engine uses in-cylinder (direct fuel injection, the fuel injection timing as controlled byECU 40 can play a role in control of the mixture temperature, hence the autoignition timing, due to the charge cooling effect of fuel evaporation. In general, later fuel injection results in lower mixture temperature before compression. That is, the charge before fuel injection (i.e., without charge cooling by fuel evaporation) is hotter, increasing heat transfer from the hot burned gas to the port walls. The fuel injection timing is constrained by the requirement of fuel-air mixing. Fuel droplets need time to vaporize and mix with the air. -
FIG. 4 illustrates another embodiment of the invention where the intake valve opening time IVO is controlled in a manner to control the air-fuel ratio incombustion chamber 12 and the closing time EVC of theexhaust valve 28 is varied relative to TDC (e.g., retarded toward TDC) over successive exhaust cycles in a manner that changes the temperature of the air/residual burned gas mixture into which fuel is mixed in thecombustion chamber 12 and thus the autoignition timing. - For example,
FIG. 4 illustrates an embodiment of the present invention where the intake air mass is controlled by the intake valve opening time and dosing time so long as in-cylinder pressure at the time of intake valve opening is fixed. As shown the intake valve opening and closing times IVO, IVC under fixed operating conditions of engine speed and torque are substantially fixed or constant relative to TDC for each intake stroke. At a fixed engine speed, the air-fuel ratio incombustion chamber 12 can be controlled to the stoichiometric proportion byECU 40 determining engine torque and controlling the intake valve opening time in response to the determined engine torque. - The exhaust valve lift timing is used to control the temperature of the fresh air-residual burned gas mixture in the
combustion chamber 12 and thus the autoignition temperature before compression. When the exhaust valve dosing times are retarded over successive exhaust strokes relative to TDC as represented bycurves FIG. 4 , more and more hot trapped residual burned gas can flow out of thecombustion chamber 12 into theexhaust port 18 and then flow back into the combustion chamber during the subsequent second exhaust event EV2 occurring after TDC represented bycurves 1′, 2′, 3′ to reduce thermal energy by heat transfer and thereby control the temperature of the burned gas mixture in the cylinder, The mass of the residual burned gas that mixes with fresh air inducted intocombustion chamber 12 remains essentially unchanged despite the changes of exhaust valve closing timing. The second exhaust event EVZ ends at the time when theintake valve 20 opens so as to control the in-cylinder pressure at the time of intake valve opening. This enables control of the intake air mass by the timing of the intake valve opening as described above for air-fuel ratio control purposes. - In the embodiment of
FIG. 4 , the fuel injection timing is controlled byECU 40 typically to occur after TDC since after TDC, the gases flow into the combustion chamber due to the downward movement of the piston. Therefore, the injected fuel after TDC will not flow out of the combustion chamber to the exhaust port despite the exhaust port being open. The injection timing can be adjusted byECU 40 to affect the mixture temperature as described above for incylinder (direct) fuel injection. - When the temperature of the residual burned gas in the
combustion chamber 12 is changed, the mass of the fresh intake air inducted into the combustion chamber and mixed with the burned gas mixture will also be accordingly changed by a minor amount despite the intake (in-cylinder) pressure and effective compression ratio of the engine remaining unchanged. The invention envisionsECU 40 slightly adjusting the intake valve opening time and for the fuel injection pulse width during the period when the exhaust valve dosing timing is changed as may be needed in order to compensate for this effect of temperature change of the burned gas mixture on the mass of the fresh air inducted into thecombustion chamber 12. For example.ECU 40 can move the intake valve opening time doser to TDC during the period of changing of the exhaust valve closing timing to increase the mass of fresh air inducted into thecombustion chamber 12. - To avoid engine pumping losses, the additional exhaust event EV2 is provided immediately after the
exhaust valve 28 doses in the exhaust stroke and after TDC as shown inFIG. 4 to allow some residual burned gases to be drawn from theexhaust part 18 by piston motion. The exhaust valve opening time EVO of the second exhaust event IV2 occurring after TDC is varied depending on the amount of advancement of the exhaust valve dosing time EVC of main intake event EV occurring before TDC. That is,curve 1′ of the additional exhaust event would be used whencurve 1 represents the main intake event occurring after TDC,curve 2′ of the additional intake event would be used whencurve 2 represents the main intake event occurring after TDC, and so on. As is apparent fromFIG. 4 , the crank angle from the end of the initial main exhaust event F (curves 1, 2, 3) to TDC and the crank angle from TDC to the beginning of the subsequent exhaust event EV2 (curves 1′, 2′, 3′) should be essentially equal to minimize engine pumping losses. - According to this embodiment of the invention, at any fixed engine speed the air-fuel ratio in
combustion chamber 12 can be controlled to the stoichiometric proportion byECU 40 determining engine torque and controlling the intake valve open/close timing as described above in response to the determined engine torque. The autoignition timing is adjusted byECU 40 by changing the exhaust valve closing timing as illustrated, for example, inFIG. 4 bycurves 1 through 3 over successive exhaust events. - Although the invention has been described above with respect to
FIG. 1 for controlling theintake valve 20 and theexhaust valve 28, those skilled in the art will appreciate that more than one intake valve (e.g., two intake valves) and more than one exhaust valve (e.g.. two exhaust valves) can be controlled in a manner to achieve advantages of the invention, for example, for an engine with more than two valves per cylinder, the open/close timing of the intake valves or the-exhaust valves of a cylinder can be controlled either in unison or differently. For example,FIG. 3 shows two intake events per cycle. For an engine with four valves per cylinder, the two intake valves can open and close differently such that the initial intake event IV2 is realized by one intake valve and the main intake event IV is realized by the other intake valve. Likewise, the two exhaust valves can be controlled to open and close differently when there are two exhaust events as shown inFIG. 4 such that the main exhaust EV is realized by one exhaust valve and the subsequent exhaust event EVZ is realized by the other exhaust valve. - While the invention has been described in terms of specific embodiments thereof, it is not intended to be limited thereto but rather only as set forth in the appended claims.
Claims (15)
1-19. (canceled)
20. A method for operating a 4-stroke, auto-ignited, internal combustion engine having a cylinder with an intake valve and an exhaust valve coupled thereto, comprising:
determining an operator demanded engine torque;
adjusting an opening time of the intake valve; and
adjusting an air-fuel ratio supplied to the cylinder wherein the intake valve opening time and said air-fuel ratio are adjusted in response to said operator demanded engine torque.
21. The method of claim 20 wherein an exhaust valve closing time is substantially fixed before top dead center and said intake valve opening time is varied after top dead center over successive engine cycles to provide successive intake events that change autoignition timing.
22. The method of claim 20 wherein said air-fuel ratio is adjusted over successive engine cycles to provide successive intake events that change autoignition timing.
23. The method of claim 20 wherein said intake valve opening time and said air-fuel ratio are adjusted to substantially provide said operator demanded engine torque.
24. The method of claim 20 , further comprising:
adjusting an exhaust valve closing time such that the intake valve and exhaust valve are open simultaneously wherein said exhaust valve closing time adjustment causes said air-fuel ratio adjustment.
25. A compression-ignited internal combustion engine, comprising:
a cylinder;
an intake valve coupled to said cylinder;
an exhaust valve coupled to said cylinder;
an accelerator pedal depression sensor; and
an electronic control unit electronically coupled to said intake valve, said exhaust valve, and said pedal sensor, said electronic control unit determining an operator demanded engine torque based on a signal from said pedal sensor, said electronic control unit adjusting both an opening time of said intake valve and a closing time of said exhaust valve to cause the engine to provide substantially said operator demanded engine torque.
26. The engine of claim 25 wherein said exhaust valve dosing time adjustment affects an air-fuel ratio in said cylinder.
27. The engine of claim 26 wherein said intake valve closing time adjustment affects an amount of backflow through said intake valve from said cylinder to an engine intake thereby affecting temperature of the gases in said cylinder and said autoignition timing.
28. The engine of claim 25 wherein said adjustments are made over successive engine cycles.
29. The engine of claim 25 wherein said electronic control unit commands said intake valve to open an additional time said additional time occurring prior to top dead center and said adjusted valve opening occurring after top dead center.
30. The engine of claim 25 wherein said electronic control unit commands said exhaust valve to open an additional time said additional time occurring after top dead center and said exhaust valve closing occurring prior to top dead center.
31. A computer readable storage medium having stored data representing instructions executable by a computer for controlling an internal combustion engine having a cylinder with an intake valve and an exhaust valve coupled thereto comprising:
instructions to determine an operator demanded engine torque;
instructions to adjust an opening time of the intake valve; and
instructions to adjust a closing time of the exhaust valve wherein said intake valve opening time and said exhaust closing time are adjusted in response to said operator demanded engine torque.
32. The media of claim 31 , further comprising: instructions to determine a desired autoignition time to provide said operator demanded engine torque wherein said opening time of the intake valve affects said autoignition time.
33. The media of claim 31 , further comprising: instructions to cause said adjustments in intake valve opening time and exhaust valve closing time to be made over successive engine cycles.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/138,045 US20060288966A1 (en) | 2003-01-13 | 2005-08-29 | Control of autoignition timing in a HCCI engine |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/248,349 US7093568B2 (en) | 2003-01-13 | 2003-01-13 | Control of autoignition timing in a HCCI engine |
US11/138,045 US20060288966A1 (en) | 2003-01-13 | 2005-08-29 | Control of autoignition timing in a HCCI engine |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/248,349 Continuation US7093568B2 (en) | 2003-01-13 | 2003-01-13 | Control of autoignition timing in a HCCI engine |
Publications (1)
Publication Number | Publication Date |
---|---|
US20060288966A1 true US20060288966A1 (en) | 2006-12-28 |
Family
ID=32654166
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/248,349 Expired - Lifetime US7093568B2 (en) | 2003-01-13 | 2003-01-13 | Control of autoignition timing in a HCCI engine |
US11/138,045 Abandoned US20060288966A1 (en) | 2003-01-13 | 2005-08-29 | Control of autoignition timing in a HCCI engine |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/248,349 Expired - Lifetime US7093568B2 (en) | 2003-01-13 | 2003-01-13 | Control of autoignition timing in a HCCI engine |
Country Status (2)
Country | Link |
---|---|
US (2) | US7093568B2 (en) |
DE (1) | DE10359585B4 (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070215095A1 (en) * | 2006-03-15 | 2007-09-20 | Hitachi, Ltd. | Controller for compression ignition engine |
US20090093946A1 (en) * | 2007-10-03 | 2009-04-09 | Mazda Motor Company | Method of controlling an internal combustion engine and system including the engine |
US20090229566A1 (en) * | 2006-02-20 | 2009-09-17 | Christina Sauer | Method for operating an internal combustion engine |
US20100300412A1 (en) * | 2009-06-02 | 2010-12-02 | Keegan Kevin R | Method for Optimizing Flow Performance of a Direct Injection Fuel Injector |
US20110144838A1 (en) * | 2009-12-10 | 2011-06-16 | Gm Global Technology Operations, Inc. | Fuel economy with a dual overhead cam engine and a strong hybrid |
US20130018565A1 (en) * | 2011-07-13 | 2013-01-17 | GM Global Technology Operations LLC | Method and apparatus for engine operation in homogeneous charge compression ignition and spark ignition |
US20130080026A1 (en) * | 2011-09-27 | 2013-03-28 | GM Global Technology Operations LLC | Method and apparatus for controlling combustion noise in an internal combustion engine |
Families Citing this family (42)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7093568B2 (en) * | 2003-01-13 | 2006-08-22 | Ford Global Technologies, Llc | Control of autoignition timing in a HCCI engine |
JP4054711B2 (en) * | 2003-04-21 | 2008-03-05 | 株式会社日立製作所 | Variable valve engine |
US20050183693A1 (en) * | 2004-02-25 | 2005-08-25 | Ford Global Technologies Llc | Method and apparatus for controlling operation of dual mode hcci engines |
US7128047B2 (en) | 2004-07-26 | 2006-10-31 | General Motors Corporation | Valve and fueling strategy for operating a controlled auto-ignition four-stroke internal combustion engine |
US7152559B2 (en) * | 2004-07-26 | 2006-12-26 | General Motors Corporation | Valve and fueling strategy for operating a controlled auto-ignition four-stroke internal combustion engine |
US7150250B2 (en) | 2004-07-26 | 2006-12-19 | General Motors Corporation | Valve and fueling strategy for operating a controlled auto-ignition four-stroke internal combustion engine |
WO2006096429A2 (en) * | 2005-03-03 | 2006-09-14 | General Motors Global Technology Operations, Inc. | Load transient control for direct-injection engines with controlled auto-ignition combustion |
WO2006096424A2 (en) * | 2005-03-03 | 2006-09-14 | General Motors Global Technology Operations, Inc. | Method for load transient control between lean and stoichiometric combustion modes of direct-injection engines with controlled auto-ignition combustion |
US7370616B2 (en) * | 2005-03-03 | 2008-05-13 | Gm Global Technology Operations, Inc. | Method for transition between controlled auto-ignition and spark ignition modes in direct fuel injection engines |
US7367313B2 (en) | 2005-03-03 | 2008-05-06 | Gm Global Technology Operations, Inc. | Speed transient control methods for direct-injection engines with controlled auto-ignition combustion |
DE102005031241A1 (en) * | 2005-07-01 | 2007-01-04 | Fev Motorentechnik Gmbh | Variable valve train of a piston internal combustion engine |
US7213572B2 (en) * | 2005-09-21 | 2007-05-08 | Ford Global Technologies, Llc | System and method for engine operation with spark assisted compression ignition |
GB0617726D0 (en) * | 2006-09-08 | 2006-10-18 | Atalla Naji A | Device (modifications) to improve efficiency of internal combustion engines |
US7748355B2 (en) * | 2006-09-15 | 2010-07-06 | Ford Global Technologies, Llc | Approach for facilitating engine mode transitions |
US7832370B2 (en) | 2006-11-16 | 2010-11-16 | Gm Global Technology Operations, Inc. | Low-load operation extension of a homogeneous charge compression ignition engine |
US7742868B2 (en) * | 2007-03-27 | 2010-06-22 | Gm Global Technology Operations, Inc. | Method and apparatus for controlling fuel reforming under low-load operating conditions using exhaust recompression in a homogeneous charge compression ignition engine |
US7918205B2 (en) * | 2007-05-01 | 2011-04-05 | GM Global Technology Operations LLC | Method and apparatus to control transition between HCCI and SI combustion in a direct-injection gasoline engine |
US8347849B2 (en) * | 2007-05-01 | 2013-01-08 | GM Global Technology Operations LLC | High load SI-HCCI transition by selective combustion mode switching |
US8195375B2 (en) * | 2007-08-17 | 2012-06-05 | GM Global Technology Operations LLC | Method for controlling combustion mode transitions in an internal combustion engine |
US7974766B2 (en) * | 2007-09-07 | 2011-07-05 | GM Gobal Technology Operations LLC | Valvetrain control systems with lift mode transitioning based engine synchronization timing and sensor based lift mode control |
US7845319B2 (en) * | 2007-09-07 | 2010-12-07 | Gm Global Technology Operations, Inc. | Valvetrain control systems with independent intake and exhaust lift control |
US7740003B2 (en) * | 2007-09-07 | 2010-06-22 | Gm Global Technology Operations, Inc. | Valvetrain control systems for internal combustion engines with different intake and exhaust leading modes |
US7979195B2 (en) * | 2007-09-07 | 2011-07-12 | GM Global Technology Operations LLC | Valvetrain control systems for internal combustion engines with multiple intake and exhaust timing based lift modes |
US7610897B2 (en) * | 2007-09-07 | 2009-11-03 | Gm Global Technology Operations, Inc. | Valvetrain control systems for internal combustion engines with time and event based control |
JP4858397B2 (en) * | 2007-10-15 | 2012-01-18 | 株式会社豊田自動織機 | Premixed compression ignition engine |
US7975668B2 (en) * | 2008-03-11 | 2011-07-12 | GM Global Technology Operations LLC | Spark timing and control during transitions between spark ignited combustion and homogenous charge compression ignition |
US7831374B2 (en) * | 2008-06-06 | 2010-11-09 | Southwest Research Institute | Combustion control system for internal combustion engine with rich and lean operating conditions |
FR2944559B1 (en) | 2009-04-15 | 2015-10-02 | Renault Sas | CONTROL OF FRESH AIR AND BURNER GAS INTRODUCED INTO A CYLINDER OF AN INTERNAL COMBUSTION ENGINE. |
DE102009029383A1 (en) * | 2009-09-11 | 2011-03-24 | Robert Bosch Gmbh | Method and control unit for operating a self-igniting gasoline engine |
US9073195B2 (en) | 2010-04-29 | 2015-07-07 | Black & Decker Inc. | Universal accessory for oscillating power tool |
US8616182B2 (en) * | 2010-05-24 | 2013-12-31 | GM Global Technology Operations LLC | Method and apparatus for controlling an internal combustion engine coupled to a passive selective catalytic reduction aftertreatment system |
US8347857B2 (en) * | 2010-06-24 | 2013-01-08 | GM Global Technology Operations LLC | Method and device for improving charged engines |
CN102971516A (en) * | 2010-12-28 | 2013-03-13 | 丰田自动车株式会社 | In-cylinder injection-type internal combustion engine |
DE102010056514A1 (en) * | 2010-12-31 | 2012-07-05 | Fev Gmbh | Method for reduction of nitrogen oxide emission in diesel engine of motor car, involves providing parts of exhaust gas to form residue exhaust gas in chamber, and adjusting residue gas and/or ratio between parts of gas in chamber |
US9765658B2 (en) * | 2011-03-02 | 2017-09-19 | Delphi Technologies, Inc. | Valve train system for an internal combustion engine |
US9163569B2 (en) * | 2011-08-25 | 2015-10-20 | GM Global Technology Operations LLC | Indirect HCCI combustion control |
WO2013111649A1 (en) * | 2012-01-27 | 2013-08-01 | ヤマハ発動機株式会社 | Six-cycle engine having scavenging stroke |
GB2519601B (en) * | 2013-10-28 | 2017-10-11 | Jaguar Land Rover Ltd | Torque Modulation for Internal Combustion Engine |
SE542390C2 (en) * | 2016-10-19 | 2020-04-21 | Scania Cv Ab | Method and system for controlling the intake and exhaust valves in an internal combustion engine |
US10221779B2 (en) * | 2016-12-16 | 2019-03-05 | Ford Global Technologies, Llc | System and method for providing EGR to an engine |
WO2019149381A1 (en) * | 2018-02-05 | 2019-08-08 | Volvo Truck Corporation | Method for controlling lubrication of a connecting rod bearing |
GB2582646B (en) * | 2019-03-29 | 2021-09-29 | Jaguar Land Rover Ltd | A control system and method for controlling operation of an internal combustion engine |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5197008A (en) * | 1990-01-25 | 1993-03-23 | Mitsubishi Jidosha Kokyo Kabushiki Kaisha | System for controlling the output power of a motor vehicle |
US5329912A (en) * | 1991-12-19 | 1994-07-19 | Yamaha Hatsudoki Kabushiki Kaisha | Induction system for an internal combustion engine |
US6267097B1 (en) * | 1999-05-12 | 2001-07-31 | Nissan Motor Co., Ltd. | Compression self-igniting gasoline engine |
US6305364B1 (en) * | 1999-04-30 | 2001-10-23 | Ford Global Technologies, Inc. | Internal combustion engine and operation thereof |
US6311667B1 (en) * | 1999-06-14 | 2001-11-06 | Toyota Jidosha Kabushiki Kaisha | Combustion control apparatus for internal combustion engine |
US6336436B1 (en) * | 1999-09-14 | 2002-01-08 | Nissan Motor Co., Ltd. | Compression autoignition gasoline engine |
US7093568B2 (en) * | 2003-01-13 | 2006-08-22 | Ford Global Technologies, Llc | Control of autoignition timing in a HCCI engine |
US7357119B2 (en) * | 2003-04-21 | 2008-04-15 | Hitachi, Ltd. | Variable valve type internal combustion engine and control method thereof |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3127511B2 (en) * | 1991-09-19 | 2001-01-29 | 株式会社日立製作所 | Exposure apparatus and method of manufacturing semiconductor device |
US5327856A (en) * | 1992-12-22 | 1994-07-12 | General Motors Corporation | Method and apparatus for electrically driving engine valves |
JP3683300B2 (en) * | 1995-01-27 | 2005-08-17 | 本田技研工業株式会社 | Control device for internal combustion engine |
DE19843174C2 (en) * | 1998-09-21 | 2000-08-17 | Siemens Ag | Method for controlling an internal combustion engine |
JP2001012264A (en) * | 1999-06-25 | 2001-01-16 | Nissan Motor Co Ltd | Internal combustion engine |
JP3582409B2 (en) * | 1999-06-30 | 2004-10-27 | 日産自動車株式会社 | Control method of internal combustion engine |
JP3637825B2 (en) * | 1999-12-15 | 2005-04-13 | 日産自動車株式会社 | Control device for variable valve engine |
US6405693B2 (en) * | 2000-02-28 | 2002-06-18 | Toyota Jidosha Kabushiki Kaisha | Internal combustion engine and method for controlling valve of internal combustion engine |
US6405706B1 (en) * | 2000-08-02 | 2002-06-18 | Ford Global Tech., Inc. | System and method for mixture preparation control of an internal combustion engine |
US6640754B1 (en) * | 2000-09-14 | 2003-11-04 | Yamaha Hatsudoki Kabushiki Kaisha | Ignition timing system for homogeneous charge compression engine |
JP2002256911A (en) * | 2001-02-23 | 2002-09-11 | Fuji Heavy Ind Ltd | Combustion control device of engine |
-
2003
- 2003-01-13 US US10/248,349 patent/US7093568B2/en not_active Expired - Lifetime
- 2003-12-18 DE DE10359585A patent/DE10359585B4/en not_active Expired - Fee Related
-
2005
- 2005-08-29 US US11/138,045 patent/US20060288966A1/en not_active Abandoned
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5197008A (en) * | 1990-01-25 | 1993-03-23 | Mitsubishi Jidosha Kokyo Kabushiki Kaisha | System for controlling the output power of a motor vehicle |
US5329912A (en) * | 1991-12-19 | 1994-07-19 | Yamaha Hatsudoki Kabushiki Kaisha | Induction system for an internal combustion engine |
US6305364B1 (en) * | 1999-04-30 | 2001-10-23 | Ford Global Technologies, Inc. | Internal combustion engine and operation thereof |
US6267097B1 (en) * | 1999-05-12 | 2001-07-31 | Nissan Motor Co., Ltd. | Compression self-igniting gasoline engine |
US6311667B1 (en) * | 1999-06-14 | 2001-11-06 | Toyota Jidosha Kabushiki Kaisha | Combustion control apparatus for internal combustion engine |
US6336436B1 (en) * | 1999-09-14 | 2002-01-08 | Nissan Motor Co., Ltd. | Compression autoignition gasoline engine |
US7093568B2 (en) * | 2003-01-13 | 2006-08-22 | Ford Global Technologies, Llc | Control of autoignition timing in a HCCI engine |
US7357119B2 (en) * | 2003-04-21 | 2008-04-15 | Hitachi, Ltd. | Variable valve type internal combustion engine and control method thereof |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20090229566A1 (en) * | 2006-02-20 | 2009-09-17 | Christina Sauer | Method for operating an internal combustion engine |
US7703442B2 (en) * | 2006-02-20 | 2010-04-27 | Robert Bosch Gmbh | Method for operating an internal combustion engine |
US7367310B2 (en) * | 2006-03-15 | 2008-05-06 | Hitachi, Ltd. | Controller for compression ignition engine |
US20070215095A1 (en) * | 2006-03-15 | 2007-09-20 | Hitachi, Ltd. | Controller for compression ignition engine |
US7992538B2 (en) * | 2007-10-03 | 2011-08-09 | Mazda Motor Corporation | Method of controlling an internal combustion engine and system including the engine |
US20090093946A1 (en) * | 2007-10-03 | 2009-04-09 | Mazda Motor Company | Method of controlling an internal combustion engine and system including the engine |
US20100300412A1 (en) * | 2009-06-02 | 2010-12-02 | Keegan Kevin R | Method for Optimizing Flow Performance of a Direct Injection Fuel Injector |
US20110144838A1 (en) * | 2009-12-10 | 2011-06-16 | Gm Global Technology Operations, Inc. | Fuel economy with a dual overhead cam engine and a strong hybrid |
US8527120B2 (en) * | 2009-12-10 | 2013-09-03 | GM Global Technology Operations LLC | Method and apparatus for controlling a powertrain system including an engine and electro-mechanical transmission |
US20130018565A1 (en) * | 2011-07-13 | 2013-01-17 | GM Global Technology Operations LLC | Method and apparatus for engine operation in homogeneous charge compression ignition and spark ignition |
US9074551B2 (en) * | 2011-07-13 | 2015-07-07 | GM Global Technology Operations LLC | Method and apparatus for engine operation in homogeneous charge compression ignition and spark ignition |
US20130080026A1 (en) * | 2011-09-27 | 2013-03-28 | GM Global Technology Operations LLC | Method and apparatus for controlling combustion noise in an internal combustion engine |
US9267451B2 (en) * | 2011-09-27 | 2016-02-23 | GM Global Technology Operations LLC | Method and apparatus for controlling combustion noise in an internal combustion engine |
Also Published As
Publication number | Publication date |
---|---|
US20040134449A1 (en) | 2004-07-15 |
DE10359585A1 (en) | 2004-07-29 |
US7093568B2 (en) | 2006-08-22 |
DE10359585B4 (en) | 2008-04-10 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7093568B2 (en) | Control of autoignition timing in a HCCI engine | |
US7059281B2 (en) | Four stroke engine auto-ignition combustion | |
US7080613B2 (en) | Method for auto-ignition combustion control | |
US6636797B2 (en) | Enhanced multiple injection for auto-ignition in internal combustion engines | |
US6994072B2 (en) | Method for mid load operation of auto-ignition combustion | |
US6968825B2 (en) | Control device for spark-ignition engine | |
US7684925B2 (en) | Engine warm-up of a homogeneous charge compression ignition engine | |
US8186329B2 (en) | Method for controlling a spark-ignition direct-injection internal combustion engine at low loads | |
JP4425445B2 (en) | Self-igniting engine | |
US6609493B2 (en) | System and method for enhanced combustion control in an internal combustion engine | |
US8290686B2 (en) | Method for controlling combustion mode transitions for an internal combustion engine | |
US8050846B2 (en) | Apparatus and method for controlling engine | |
EP1134398A2 (en) | System and method for auto-ignition of gasoline internal combustion engine | |
US7284531B2 (en) | Method for operating an internal combustion engine | |
US20100077990A1 (en) | Control of spark ignited internal combustion engine | |
JP4122630B2 (en) | Compression self-ignition gasoline engine | |
WO2007140132A2 (en) | Controlling transition between hcci and si combustion | |
US6983732B2 (en) | Injection strategy for operating a direct-injection controlled auto-ignition four-stroke internal combustion engine | |
KR20080107289A (en) | Method and apparatus for controlling ignition timing in a compression-ignition engine operating in an auto-ignition mode | |
CN114483351B (en) | engine system | |
CN114483353B (en) | Engine system | |
CN114483352B (en) | engine system | |
US7353799B2 (en) | Method for operating an internal combustion engine | |
JP3800881B2 (en) | Control device for direct-injection spark-ignition internal combustion engine | |
JP2004346854A (en) | Controller of compression ignition operation of internal combustion engine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: FORD MOTOR COMPANY, OREGON Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:YANG, JIALIN;REEL/FRAME:016866/0183 Effective date: 20021016 |
|
AS | Assignment |
Owner name: FORD GLOBAL TECHNOLOGIES, INC., MICHIGAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FORD MOTOR COMPANY;REEL/FRAME:017239/0671 Effective date: 20021211 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |