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
  • F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
  • F02D19/06—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
  • F02D19/0663—Details on the fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
  • F02D19/0686—Injectors
  • F02D19/0689—Injectors for in-cylinder direct injection
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
  • F02D19/06—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
  • F02D19/08—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed simultaneously using pluralities of fuels
  • F02D19/082—Premixed fuels, i.e. emulsions or blends
  • F02D19/084—Blends of gasoline and alcohols, e.g. E85
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
  • F02D19/06—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
  • F02D19/08—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed simultaneously using pluralities of fuels
  • F02D19/082—Premixed fuels, i.e. emulsions or blends
  • F02D19/085—Control based on the fuel type or composition
  • F02D19/087—Control based on the fuel type or composition with determination of densities, viscosities, composition, concentration or mixture ratios of fuels
  • F02D19/088—Control based on the fuel type or composition with determination of densities, viscosities, composition, concentration or mixture ratios of fuels by estimation, i.e. without using direct measurements of a corresponding sensor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D35/00—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for
  • F02D35/02—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions
  • F02D35/023—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions by determining the cylinder pressure
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D35/00—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for
  • F02D35/02—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions
  • F02D35/028—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions by determining the combustion timing or phasing
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/06—Fuel or fuel supply system parameters
  • F02D2200/0611—Fuel type, fuel composition or fuel quality
  • F02D2200/0612—Fuel type, fuel composition or fuel quality determined by estimation
• • 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
  • Y02T10/30—Use of alternative fuels, e.g. biofuels

Definitions

• the present invention relates to a control device for an internal combustion engine, and more particularly to a control device for an internal combustion engine having a function of determining fuel properties.
• a heat generation amount parameter that correlates with the combustion rate is calculated, and the cetane number of the fuel is measured based on a change in the heat generation amount parameter in a predetermined operation state.
• a heat generation amount parameter that correlates with the combustion rate is calculated, and the cetane number of the fuel is measured based on a change in the heat generation amount parameter in a predetermined operation state.
• an object of the present invention is to provide means for accurately discriminating fuel properties. Disclosure of the invention
• the control apparatus for an internal combustion engine includes an in-cylinder pressure detecting means for detecting an in-cylinder pressure in a combustion chamber of the internal combustion engine, and a heat for calculating a heat generation amount parameter indicating a combustion state based on the detected in-cylinder pressure.
• Generation amount parameter calculation means combustion delay calculation means for calculating a combustion delay based on the detected in-cylinder pressure, the calculated heat generation amount parameter and combustion delay, and a heat generation amount parameter corresponding to the reference fuel
• a fuel property determining means for determining the fuel property based on the comparison with the combustion delay.
• the heat generation amount parameter calculating means calculates a product value of the detected in-cylinder pressure and a value raised to a value near the specific heat ratio of the air-fuel mixture supplied with the combustion chamber volume at the time of detection of the in-cylinder pressure. It is preferable to calculate as the heat generation amount parameter.
• the fuel property determining means preferably compares the average value of the detected heat generation amount parameter for each cycle with the average value of the heat generation parameter corresponding to the reference fuel for each cycle. Further, the integrated value for each cycle of the heat generation amount parameter may be compared with the integrated value for each cycle of the heat generation amount parameter corresponding to the reference fuel.
• the heat generation amount parameter calculation means preferably calculates a value obtained by dividing the indicated heat amount by a low heat generation amount as the heat generation amount parameter.
• the combustion delay calculation means calculates the combustion delay based on a change amount of the combustion ratio.
• a switching unit that switches a plurality of control value maps based on the determination result of the fuel property determination unit.
• FIG. 1 is a schematic configuration diagram showing an internal combustion engine to which a control device according to the present invention is applied.
• FIG. 2 is a flowchart showing a fuel property determination process in the internal combustion engine of FIG.
• Figure 3 is a graph showing the relationship between the combustion rate and the combustion delay.
• Figure 4 shows the heat generation parameters for alcohol blended fuel and gasoline fuel. It is a graph which shows transition of.
• Fig. 5 is a graph showing the relationship between the alcohol content in the fuel, the heat generation parameter, and the combustion delay.
• the higher the alcohol content in the fuel the smaller the heat generation and the smaller the combustion delay. Therefore, in the present invention, it is possible to accurately determine the fuel property by determining the fuel property based on both the heat generation amount parameter and the combustion delay.
• the heat generation amount parameter calculating means calculates the detected in-cylinder pressure P and a value obtained by raising the combustion chamber volume V at the time of detection of the in-cylinder pressure P to a value near the specific heat ratio / c of the supplied air-fuel mixture. It is preferable to calculate the product value PV K as the heat generation amount parameter.
• PV K has a high correlation with the amount of heat generated in the combustion chamber.
• the properties of the fuel can be determined with higher accuracy.
• the in-cylinder pressure P can be directly detected by the in-cylinder pressure sensor, and the volume (in-cylinder volume) V can be uniquely determined from the crank angle by a predetermined map or function.
• the constant ⁇ may be a value near the specific heat ratio of the air-fuel mixture formed in the combustion chamber, and even if it is a predetermined fixed value, it should be changed according to the intake air amount, the fuel injection amount, etc. It may be.
• FIG. 1 is a schematic configuration diagram showing an internal combustion engine to which a control device according to the present invention is applied.
• the internal combustion engine 1 shown in the figure burns a mixture of fuel and air inside the combustion chamber 3 formed in the cylinder block, and power is generated by reciprocating the piston 4 in the combustion chamber 3. Is generated.
• the internal combustion engine 1 can be operated with gasoline and with a mixed fuel of gasoline and alcohol.
• the internal combustion engine 1 is preferably configured as a multi-cylinder engine, and the internal combustion engine 1 of the present embodiment is configured as a 4-cylinder engine, for example.
• each combustion chamber 3 is connected to an intake pipe (intake manifold) 5, and the exhaust port of each combustion chamber 3 is connected to an exhaust pipe 6 (exhaust manifold hold).
• an intake valve V i and an exhaust valve V e are provided for each combustion chamber 3 in the cylinder head of the internal combustion engine 1.
• Each intake valve V i opens and closes the corresponding intake port
• each exhaust valve V e opens and closes the corresponding exhaust port.
• Each intake valve V i and each exhaust valve V e are opened and closed by a valve operating mechanism VM including a variable valve timing mechanism.
• the internal combustion engine 1 has a number of ignition brags 7 corresponding to the number of cylinders, and the ignition brags 7 are arranged in the cylinder heads so as to face the corresponding combustion chambers 3.
• the intake pipe 5 is connected to a surge tank 8 as shown in FIG.
• the surge tank 8 is connected to an air supply line L 1, and the air supply line L 1 is connected to an air intake port (not shown) via an air cleaner 9.
• a throttle valve (in this embodiment, an electronically controlled throttle valve) 10 is incorporated in the air supply line L 1 (between the surge tank 8 and the air cleaner 9).
• a front-stage catalyst device 11 a including a three-way catalyst and a rear-stage catalyst device 11 b including, for example, a NOx storage reduction catalyst are connected to the exhaust pipe 6.
• the internal combustion engine 1 has a plurality of injectors 12, and each injector 12 is disposed in a cylinder head so as to face the corresponding combustion chamber 3 as shown in FIG. 1. .
• Each piston 4 of the internal combustion engine 1 is configured as a so-called deep dish top surface type, and has a recess 4 a on the upper surface thereof.
• each combustion chamber 3 In a state where air is sucked into the fuel, fuel such as gasoline is directly injected from each injector 12 toward the recess 4 a of the piston 4 in each combustion chamber 3.
• the fuel / air mixture layer is formed (stratified) in the vicinity of the ignition plug 7 in a state separated from the surrounding air layer, so an extremely lean mixture is used. And stable stratified combustion can be performed.
• the internal combustion engine 1 of the present embodiment is described as a so-called direct injection engine, but is not limited to this, and the present invention can be applied to an intake pipe (intake port) injection type internal combustion engine. Needless to say.
• E C U 20 Each of the spark plugs 7, the throttle valve 10, the injectors 12, the valve operating mechanism VM and the like described above are electrically connected to E C U 20 that functions as a control device for the internal combustion engine 1.
• E C U 20 includes C P U, ROM, R AM, I / O port, storage device, etc., all not shown.
• various sensors including the crank angle sensor 14 of the internal combustion engine 1 are electrically connected to the E C U 20.
• the ECU 20 uses an ignition plug ⁇ , a throttle valve 10, and an injector 1 so that a desired output can be obtained based on detection values of various sensors using various maps stored in the storage device. 2. Control the valve mechanism VM.
• the internal combustion engine 1 has in-cylinder pressure sensors (in-cylinder pressure detecting means) 15 including semiconductor elements, piezoelectric elements, magnetostrictive elements, optical fiber detecting elements, and the like corresponding to the number of cylinders.
• Each in-cylinder pressure sensor 15 is disposed on the cylinder head so that the pressure receiving surface faces the corresponding combustion chamber 3, and is electrically connected to the ECU 20 via an AZD converter or the like (not shown). ing.
• Each in-cylinder pressure sensor 15 outputs the pressure (in-cylinder pressure) applied to the pressure receiving surface in the combustion chamber 3 as a relative value to the atmospheric pressure, and the pressure applied to the pressure receiving surface (in-cylinder pressure) A corresponding voltage signal (signal indicating the detected value) is supplied to the ECU 20.
• the internal combustion engine 1 has an intake pressure sensor 16 that detects the pressure (intake pressure) of the intake air in the surge tank 8 as an absolute pressure.
• the intake pressure sensor 1 6 is also not shown. It is electrically connected to the ECU 20 via an AZD converter or the like, and gives a signal indicating the detected absolute pressure of the intake air in the surge tank 8 to the ECU 20.
• the detection values of the crank angle sensor 14 and the intake pressure sensor 16 are sequentially given to the ECU 20 every minute time, and are stored and held by a predetermined amount in a predetermined storage area (buffer) of the ECU 20.
• each in-cylinder pressure sensor 15 is subjected to absolute pressure correction based on the detection value of the intake pressure sensor 16 and then is stored in a predetermined storage area (buffer) of the ECU 20 by a predetermined amount. Stored and retained.
• the ROM of the ECU 20 stores two types of fuel injection amount maps, two types of injection timing maps, and two types of ignition timing maps created in advance.
• One of each of the two map types corresponds to gasoline fuel, and the other corresponds to gasoline / alcohol mixed fuel.
• Each map is configured such that, for example, the intake air amount and the engine speed are input variables, and the fuel injection amount, the injection timing, and the ignition timing can be read according to these values.
• the ECU 20 ROM also contains various other parameters indicating the operating conditions such as intake air temperature, throttle opening, and engine water temperature for the fuel injection amount, injection timing, and ignition timing read from these maps. A function and a program for performing correction based on this are stored.
• the ECU 20 executes a fuel property determination process shown in FIG.
• the processing by this routine is executed in the first cycle after starting, but may be executed at any time within a predetermined period from the starting time.
• the ECU 20 first reads a parameter indicating the engine condition (S10).
• the parameter read here is one or more types indicating whether or not the engine has been warmed up, for example, the engine water temperature.
• the ECU 20 compares the read parameter with a predetermined reference value to determine whether or not the engine has been warmed up (S20). If the engine has been warmed up, the process is returned.
• the ECU 20 detects the combustion state of each combustion chamber (S30).
• the detection values of the in-cylinder pressure sensor 15 at a plurality of predetermined crank angles are acquired for each cylinder and stored in a predetermined storage area of the ECU 20.
• the ECU 20 determines the value of PV K from the in-cylinder pressure P, the in-cylinder volume V at the predetermined reference crank angle, and the specific heat ratio ⁇ determined in advance as described above or a value close thereto as a heat generation amount parameter. Calculation is made for each cylinder (S 40) and stored in a predetermined storage area of the ECU 20.
• the ECU 20 calculates the value of the combustion delay d CS for each cylinder by a predetermined function (S 50), and stores it in a predetermined storage area of the ECU 20.
• the combustion delay d CS can be obtained from the in-cylinder pressure P and the in-cylinder volume V force at a plurality of crank angles acquired in step S30. Specifically, the heat generation amount parameter PV K at multiple crank angles is calculated, and from these value powers, for example, 180 ° ATDC, which is considered to be sufficiently earlier than the start of combustion.
• the combustion ratio MFB which is the ratio of the amount of heat generated between the two points up to the specified timing with respect to the total amount of heat generated (at 1 35 ° ATDC, which is considered to be sufficiently later than the end of combustion).
• the rising point t 1 of the combustion ratio MFB is obtained by a predetermined function.
• a predetermined function is determined, for example, as the rising point t 1 when AMFB, which is the amount of change in the combustion rate MFB in the minute time ⁇ t, exceeds a predetermined reference value.
• the time difference between the ignition timing t 0 and the rising point t 1 is calculated and stored for each cylinder as the combustion delay d CS.
• the processes in steps S30 to S50 are repeated until one cycle is completed for all cylinders (S60).
• the average value mean ( ⁇ PV differs depending on the fuel properties. In the case of alcohol-mixed fuel, the average value is larger than that of gasoline fuel.
• the value mean (APV is compared with the reference value ⁇ , which is the average value of the amount of heat generated by the parameter ⁇ ⁇ ⁇ from the intake bottom dead center ⁇ PV for each cycle, corresponding to the reference fuel (gasoline).
• the ECU 20 calculates the average value for each cycle of the combustion delay d CS and the value in the reference fuel (gasoline). Compare (S 80) Specifically, the ECU 20 adds the value of the combustion delay d CS calculated in step S 50 for each cycle according to the following equation (2), and calculates this as the number of cylinders n.
• the average value mean (dCS) is compared with the reference value ⁇ of the combustion delay d C S corresponding to the reference fuel.
• the ECU 20 determines the fuel ignitability and A predetermined alcohol mixed fuel use flag in 20 RAMs is set to 1 (S90). This alcohol mixed fuel use flag is appropriately referred to in the next response control and other control.
• the gasoline fuel ECU 20 is used in the above alcohol blended fuel. Reset the use flag to 0 (S 1 1 0).
• E C U 20 switches the operation map (S 100). Specifically, according to the reference to the above alcohol blended fuel use flag, if alcohol blended fuel is used among the two types of fuel injection amount maps, fuel injection timing maps, and ignition timing maps, alcohol mixing is used. If fuel is selected, and if gasoline fuel is used, then it is selected for gasoline fuel and used for control of fuel injection amount / injection timing and ignition timing, respectively.
• the control map for the alcohol-mixed fuel is selected, It will be used to control the engine.
• the present embodiment it is possible to accurately determine the fuel property by determining the fuel property based on both the heat generation amount parameter and the combustion delay. Further, in the present embodiment, since the fuel property can be determined at the initial stage of start-up, the corresponding control can be quickly switched. .
• the S ZN ratio of the detection value is increased. This makes it possible to improve detection accuracy.
• the value (heat generation rate) obtained by dividing the heat generation amount ⁇ ⁇ V K, which is the indicated heat amount, by the lower heating value Q fue l is used as the heat generation amount parameter, so the influence of the fuel injection amount Tau It can be reflected correctly and the detection accuracy can be improved.
• the combustion delay dCS is calculated based on the amount of change in the combustion ratio, the expected effect of the present invention can be obtained with a simple configuration.
• the present invention since a plurality of control value maps created in advance for each fuel property are switched based on the determination result of the fuel property, the desired effect can be obtained in the present invention with a simple configuration. it can.
• the present invention has been described with a certain degree of concreteness, but various modifications and changes can be made to the present invention without departing from the spirit and scope of the invention described in the claims. It must be understood that it is possible. In other words, the present invention includes modifications and changes that fall within the scope and spirit of the appended claims and their equivalents.
• the average value for each cycle of the heat generation amount parameter is compared with the reference value.
• the integrated value for each cycle of the heat generation amount parameter is set to the heat value corresponding to the reference fuel. It may be compared with the integrated value of each generation parameter for each cycle, and in this case there is a similar advantage.
• the correspondence control using the fuel property determination result is realized by switching a plurality of maps.
• the response control in the present invention is performed by switching a plurality of functions according to the fuel property determination result.
• Control variable ⁇ May be realized by correcting constants.
• the present invention drives an internal combustion engine that uses other types of fuel or various internal combustion engines. It can also be applied to hybrid vehicles included as a source.
• the present invention can be used for accurately discriminating fuel properties.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)
• Output Control And Ontrol Of Special Type Engine (AREA)
• Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=39738291

Family Applications (1)

Country Status (5)

Cited By (1)

Families Citing this family (14)

Citations (3)

Family Cites Families (6)

• 2007
  • 2007-03-02 JP JP2007053260A patent/JP4784868B2/ja not_active Expired - Fee Related
• 2008
  • 2008-02-28 CN CN2008800068933A patent/CN101627201B/zh not_active Expired - Fee Related
  • 2008-02-28 DE DE112008000554T patent/DE112008000554B4/de not_active Expired - Fee Related
  • 2008-02-28 US US12/529,607 patent/US8051836B2/en not_active Expired - Fee Related
  • 2008-02-28 WO PCT/JP2008/054001 patent/WO2008108419A1/ja not_active Ceased

Patent Citations (3)

Also Published As

Similar Documents

Legal Events