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
  • F02D41/30—Controlling fuel injection
  • F02D41/38—Controlling fuel injection of the high pressure type
  • F02D41/3809—Common rail control systems
  • F02D41/3836—Controlling the fuel pressure
  • F02D41/3863—Controlling the fuel pressure by controlling the flow out of the common rail, e.g. using pressure relief valves
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/14—Introducing closed-loop corrections
  • F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/14—Introducing closed-loop corrections
  • F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
  • F02D2041/141—Introducing closed-loop corrections characterised by the control or regulation method using a feed-forward control element
• • 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
  • F02D2200/0602—Fuel pressure
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2250/00—Engine control related to specific problems or objectives
  • F02D2250/31—Control of the fuel pressure

Definitions

• the invention firstly relates to a method for operating a fuel system of an internal combustion engine, in which a pressure control device is precontrolled with a pilot signal, which is determined taking into account a desired pressure in a region of the fuel system, in particular a fuel pressure accumulator.
• the invention further relates to a computer program, an electrical storage medium for a control and / or regulating device of an internal combustion engine, a control and / or regulating device for an internal combustion engine, and an internal combustion engine, in particular for a motor vehicle.
• EP 1 086 307 Bl A method of the aforementioned type is known from EP 1 086 307 Bl.
• Both the high-pressure fuel pump and the pressure control valve are controlled by a controller with which a certain Pressure can be set or adjusted in the fuel pressure accumulator.
• a feedforward control is provided.
• the pressure control valve is thereby precontrolled, inter alia, depending on a desired pressure in the fuel pressure accumulator.
• the present invention has the object, a method of the type mentioned so on to form that the pressure in the fuel pressure accumulator with even higher
• This object is achieved in a method of the type mentioned in that in the determination of the pilot signal, a value for a passing through the pressure regulating device fuel quantity is taken into account.
• a value for a passing through the pressure regulating device fuel quantity is taken into account.
• the control signal which is required to maintain a certain pressure in a region of the fuel system depends on the amount of fuel which flows out of the region through the pressure control device.
• the desired pressure can be set with much higher accuracy and better dynamics.
• the required control actions are correspondingly smaller, which also benefits the dynamics of adjusting the pressure in the fuel pressure accumulator.
• a pressure regulating device when using the method according to the invention, can be used which is manufactured with greater tolerances, since the greater the tolerances, the greater the dependence of the control signal required for a certain pressure in the region on the fuel quantity flowing through the pressure regulating device. with which the pressure control device is made. However, since this dependency is considered according to the invention, the corresponding tolerances of the pressure control device only play a diminished role.
• a quantity of fuel delivered by a high-pressure fuel pump is taken into account in determining the value for the fuel quantity flowing through the pressure regulating device. This is based on the idea that when a certain pressure level is to be maintained in the fuel pressure accumulator, for example, the greater the amount of fuel delivered by the high-pressure fuel pump, the greater the amount of fuel flowing through the pressure control device.
• Pressure control device is thereby simplified and at the same time its precision is improved.
• Pressure control device flowing through amount of fuel considerably.
• the method according to the invention is simple to implement when a factor is determined from the value for a fuel quantity flowing through the pressure regulating device, with which a raw pilot signal which takes into account a desired pressure in the region of the fuel system, in particular in the fuel pressure accumulator is determined, is applied.
• Figure 1 is a schematic representation of an internal combustion engine with a fuel system with a pressure control device
• FIG. 2 shows a flow diagram of a method for determining a pilot control signal for precontrol of the pressure control device of FIG. 1.
• An internal combustion engine carries the reference numeral 10 in its entirety in FIG. 1. It comprises a fuel system, which is denoted by 12.
• Part of the fuel system 12 is a fuel tank 14, from which an electrically driven prefeed pump 16 conveys the fuel to a mechanically driven high-pressure fuel pump 18. Their delivery rate can be adjusted by a quantity control valve or metering unit 20.
• the high-pressure fuel pump 18 delivers the fuel into a fuel pressure accumulator 22, to which a plurality of injectors 24 are connected.
• the fuel pressure accumulator 22 is also referred to as "rail".
• the injectors 24 inject the fuel directly into them directly
• Combustion chambers 26 a During operation of the internal combustion engine 10, a crankshaft 28 is set in rotation, the speed of which is detected by a sensor 29 and which drives the high-pressure fuel pump 18 via a mechanical connection 30.
• an adjustable or controllable pressure control device 32 This may, for example, be a pressure regulating valve with a spring-loaded valve element.
• the biasing force of the force acting on the valve element spring can be varied by means of an electromagnetic actuator.
• the corresponding drive signal supplies a control and regulating device 34, which receives inter alia input signals from a pressure sensor 36, which detects the pressure in the fuel pressure accumulator 22.
• the pressure control device 32, the fuel pressure accumulator 22, the control and regulating device 34 and the pressure sensor 36 thus form a closed controlled system.
• a desired pressure in the fuel pressure accumulator 22 is defined depending on the state and operating variables of the internal combustion engine 10.
• the state and operating variables which can influence the desired pressure in the fuel pressure accumulator 22 include, for example, the operating mode of the internal combustion engine 10, the load or the torque, which depends on the Internal combustion engine 10 is to be made, the speed detected by the sensor 29, with which the crankshaft 28 rotates, a temperature of the internal combustion engine 10, et cetera.
• the pressure control device 32 is piloted. This means that, taking into account the desired pressure of the control and regulating device 34 with the interposition of a final stage, a pilot signal in the form of a pilot control current I DRV is generated. Due to the closed loop described above then only correspondingly small deviations must be compensated. The provision of the pilot current I DRV will now be explained in detail with reference to FIG. 2:
• the speed nmot of the crankshaft 28 provided by the rotational speed sensor 29 is fed into a characteristic curve 38 which determines from the rotational speed nmot a delivery rate q ro p of the high-pressure fuel pump 18.
• the characteristic curve 38 is based on the assumption that the metering unit 20 is set so that it does not limit the delivery rate of the high-pressure fuel pump 18.
• QiNj is the amount of fuel that is injected from the injectors 24 into the combustion chambers 26.
• q C0 N is the Abgres fuel quantity, which is used by the injectors 24 for the actuation thereof, and which is returned via a designated in Figure 1 at 42 return line to the fuel tank 14.
• the amount of fuel qi NJ is also controlled by the control and regulating device 34 depending on state and Operating variables and determined depending on the desired torque. Depending on this, the return flow fuel quantity q C0 N results, for example, by means of a characteristic curve.
• the sum value formed in 40 corresponds to that
• This value is fed together with the value provided by the pressure sensor 36 for the actual pressure pr_ist, which prevails in the fuel pressure accumulator 22, in a map 46 which generates a correction factor KF.
• This is multiplied in 48 by a raw pilot current I * DRV , which was generated by means of a characteristic curve 50, into which a desired pressure pr soll, which should prevail in the fuel pressure accumulator 22, was fed.
• the result of the multiplication in block 48 is the pilot control current I DRV ⁇ with which the pressure control device 32 is precontrolled .
• the correction factor KF takes into account that the current required to be applied to the
• Pressure control device 32 to set a specific opening pressure, from the flowing through the pressure control device 32 fuel quantity q D Rv and the current actual pressure pr_ist, in the fuel pressure accumulator 22nd prevails, depends.
• the method described is stored as a computer program in a memory of the control and regulating device 34.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
• Fuel-Injection Apparatus (AREA)
• Output Control And Ontrol Of Special Type Engine (AREA)

Applications Claiming Priority (2)

Publications (2)

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Family Applications (1)

Country Status (6)

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Family Cites Families (16)

• 2004
  • 2004-12-09 DE DE102004059330A patent/DE102004059330A1/de not_active Withdrawn
• 2005
  • 2005-10-20 EP EP05797117A patent/EP1825125B1/fr active Active
  • 2005-10-20 WO PCT/EP2005/055417 patent/WO2006061288A1/fr active Application Filing
  • 2005-10-20 JP JP2007544860A patent/JP4518515B2/ja not_active Expired - Fee Related
  • 2005-10-20 AT AT05797117T patent/ATE455949T1/de not_active IP Right Cessation
  • 2005-10-20 US US11/792,898 patent/US9611800B2/en not_active Expired - Fee Related
  • 2005-10-20 DE DE502005008928T patent/DE502005008928D1/de active Active

Non-Patent Citations (1)

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