Search

CN-121976891-A - Method, device, equipment and storage medium for controlling oil injection

CN121976891ACN 121976891 ACN121976891 ACN 121976891ACN-121976891-A

Abstract

The application provides a method, a device, equipment and a computer readable storage medium for controlling oil injection, wherein the method comprises the steps of acquiring the running parameters of a vehicle; the method comprises the steps of determining the Miller degree in a target cylinder of a Miller cycle engine at the current moment, wherein the Miller degree is used for representing the intensity of the Miller cycle in the target cylinder, determining the oil injection parameters of the target cylinder through a preset oil injection control model based on the Miller degree and the running parameters of a vehicle, wherein the oil injection parameters are used for compensating the change of the thermodynamic state in the target cylinder caused by the Miller cycle, and controlling a target oil injector corresponding to the target cylinder to execute fuel injection according to the oil injection parameters.

Inventors

  • Tuo chao

Assignees

  • 重庆长安汽车股份有限公司

Dates

Publication Date
20260505
Application Date
20260316

Claims (12)

  1. 1. A method of controlling fuel injection, the method being applied to a vehicle including a miller cycle engine, the method comprising: Acquiring operation parameters of a vehicle; determining the Miller degree in a target cylinder of the Miller cycle engine at the current moment, wherein the Miller degree is used for representing the intensity of the Miller cycle in the target cylinder; Determining an oil injection parameter of the target cylinder through a preset oil injection control model based on the Miller degree and the running parameter of the vehicle, wherein the oil injection parameter is used for compensating the change of the thermodynamic state in the target cylinder caused by Miller circulation; and controlling a target fuel injector corresponding to the target cylinder to execute fuel injection according to the fuel injection parameters.
  2. 2. The method of claim 1, wherein the determining a degree of miller in a target cylinder of the miller cycle engine at a current time comprises: acquiring an opening angle and a closing angle of an intake valve of the target cylinder under the current working cycle; Determining the Miller degree in the target cylinder at the current moment based on a preset Miller degree calculation model, the inlet valve opening angle and the inlet valve closing angle, wherein the Miller degree calculation model is used for quantifying the Miller degree in the cylinder based on the inlet valve opening and closing angle and the structural parameters of the cylinder.
  3. 3. The method of claim 1 or 2, wherein the injection parameters include a target rail pressure, the injection control model is a first modified model, and the determining the injection parameters of the target cylinder based on the miller level and the operating parameters of the vehicle by a preset injection control model comprises: determining that the vehicle is in a steady state condition or a transient condition based on the operating parameters of the vehicle; if the vehicle is in a steady-state working condition, taking a preset basic rail pressure as the target rail pressure; and if the vehicle is in a transient working condition, correcting the basic rail pressure to obtain the target rail pressure through a first correction model based on the Miller degree and the running parameters of the vehicle.
  4. 4. A method according to claim 3, wherein said correcting said base rail pressure to said target rail pressure based on said degree of miller and said operating parameters of said vehicle by a first correction model comprises: Acquiring the gas pressure change rate in an air inlet pipeline of the target cylinder in the air inlet stage; Determining a target correction coefficient based on the current rotation speed of the Miller cycle engine and a first mapping relation, wherein the first mapping relation is a corresponding relation between the rotation speed of the Miller cycle engine calibrated in advance and the correction coefficient; Determining a rail pressure correction amount based on the gas pressure change rate, the target correction coefficient and the Miller degree by adopting the first correction model, wherein the rail pressure correction amount is inversely related to the Miller degree and positively related to the gas pressure change rate; And adding the rail pressure correction amount to the basic rail pressure to obtain the target rail pressure.
  5. 5. The method according to claim 1 or 2, wherein the injection parameters include an injection start angle and/or an injection cone angle, wherein the injection control model is a first mapping model, wherein the determining the injection parameters of the target cylinder by a preset injection control model based on the miller level and the vehicle operating parameters comprises: determining that the vehicle is in a steady state condition or a transient condition based on the operating parameters of the vehicle; And if the vehicle is in a steady-state working condition, determining an oil injection starting angle and/or an oil injection cone angle based on the Miller degree and the first mapping model, wherein the first mapping model defines a one-to-one mapping relation between a plurality of Miller degree intervals and a plurality of oil injection starting angles and/or oil injection cone angles.
  6. 6. The method of claim 5, wherein the fuel injection parameters further comprise a target pre-injection fuel injection quantity, wherein the fuel injection control model is a third modified model, and wherein the method further comprises: if the vehicle is in a transient working condition, determining an oil quantity correction quantity based on the Miller degree and a third correction model, wherein the oil quantity correction quantity is inversely related to the Miller degree; and adding the oil quantity correction to the basic pre-injection oil quantity to obtain the target pre-injection oil quantity.
  7. 7. The method of claim 5, wherein the fuel injection control model is a fourth correction model, the method further comprising: If the vehicle is in a transient working condition, obtaining an oil injection starting angle correction quantity based on the Miller degree, the current rotating speed of the Miller cycle engine and a fourth correction model, wherein the oil injection starting angle correction quantity is inversely related to the Miller degree and positively related to the current rotating speed of the Miller cycle engine; and subtracting the correction amount of the oil injection starting angle from the basic oil injection starting angle to obtain the target oil injection starting angle.
  8. 8. The method of claim 1 or 2, wherein the injection parameter comprises a target injection pulse width and the injection control model is a fifth modified model, the method further comprising: The method comprises the steps of obtaining the load change rate of the Miller cycle engine and the Miller degree change rate of the target cylinder, wherein the Miller degree change rate is determined based on the Miller degree of the current working cycle and the Miller degree of the previous N working cycles, and N is an integer greater than or equal to 1; determining an oil injection pulse width compensation quantity based on the load change rate and the Miller degree change rate by adopting the fifth correction model, wherein the oil injection pulse width compensation quantity is in direct proportion to the load change rate and the Miller degree change rate; And adding the oil injection pulse width compensation quantity with a basic oil injection pulse width to obtain the target oil injection pulse width.
  9. 9. The method of claim 2, wherein the determining the degree of miller within the target cylinder based on the intake valve opening angle and the intake valve closing angle comprises: Determining a miller level in the target cylinder based on the intake valve opening angle and the intake valve closing angle if an effective intake valve opening angle and intake valve closing angle are obtained; And if the invalid opening angle and/or closing angle of the intake valve are not obtained or are obtained, determining the Miller degree in the target cylinder based on a second mapping relation, the current rotating speed and the current load of the Miller cycle engine, wherein the second mapping relation is a corresponding relation between the rotating speed and the load of the pre-calibrated Miller cycle engine and the Miller degree.
  10. 10. An apparatus for controlling injection of fuel for use in a vehicle including a miller cycle engine, the apparatus comprising: a signal acquisition unit for acquiring an operation parameter of the vehicle; The miller degree calculation unit is used for determining the miller degree in a target cylinder of the miller cycle engine at the current moment, wherein the miller degree is used for representing the intensity of the miller cycle in the target cylinder; The processing unit is used for determining the oil injection parameter of the target cylinder through a preset oil injection control model based on the Miller degree and the running parameter of the vehicle, wherein the oil injection parameter is used for compensating the change of the thermodynamic state in the target cylinder caused by Miller circulation; And the control unit is used for controlling a target fuel injector corresponding to the target cylinder to execute fuel injection according to the fuel injection parameters.
  11. 11. An apparatus for controlling injection of fuel for use in a vehicle including a miller cycle engine, the apparatus comprising: One or more processors; a memory for storing one or more programs that, when executed by the one or more processors, cause the control device to implement the method of any of claims 1-9.
  12. 12. A computer-readable storage medium, having stored thereon a computer program which, when executed by a processor of a computer, causes the computer to perform the method of any of claims 1 to 9.

Description

Method, device, equipment and storage medium for controlling oil injection Technical Field The present application relates to the field of engine control technology, and in particular, to a method, an apparatus, a device, and a computer readable storage medium for controlling fuel injection. Background The miller cycle achieves expansion ratios greater than compression ratios by adjusting early or late intake valve closing in the cylinders of the engine is a key technique to improve engine thermal efficiency. Wherein the engine may be a miller cycle engine. The miller cycle engine, i.e. the operating mode, is a miller cycle engine. However, when the miller cycle is applied to an engine, the dynamically changing in-cylinder conditions caused by the miller cycle provide great challenges for the fuel injection system, and at present, problems such as higher air-fuel ratio, excessive particulate matter emissions, vehicle torque fluctuation and the like exist. Disclosure of Invention The application aims to provide a method for controlling oil injection, which is used for solving the problems of higher air-fuel ratio, exceeding particulate matter emission standard, fluctuation of vehicle torque and the like of a Miller cycle engine, and aims to provide a device for controlling oil injection, equipment for controlling oil injection, a computer readable storage medium and a computer program. In order to achieve the above purpose, the technical scheme adopted by the application is as follows: The embodiment of the application provides a method for controlling oil injection, which is applied to a vehicle comprising a Miller cycle engine and comprises the steps of obtaining the running parameters of the vehicle; the method comprises the steps of determining the Miller degree in a target cylinder of a Miller cycle engine at the current moment, wherein the Miller degree is used for representing the intensity of the Miller cycle in the target cylinder, determining the oil injection parameters of the target cylinder through a preset oil injection control model based on the Miller degree and the running parameters of a vehicle, wherein the oil injection parameters are used for compensating the change of the thermodynamic state in the target cylinder caused by the Miller cycle, and controlling a target oil injector corresponding to the target cylinder to execute fuel injection according to the oil injection parameters. According to the technical means, the actual compression ratio and the effective air inflow under the current working cycle are accurately reflected through real-time calculation of the Miller degree, and the oil injection parameters (such as the oil injection pulse width, the oil injection starting angle, the common rail pressure and the like) are dynamically corrected by combining with the running parameters of the engine such as the rotating speed and the load, so that the oil injection parameters are accurately matched with the actual air inflow, stable combustion of fuel in a target cylinder is ensured, air and fuel can be stabilized, and therefore the Miller cycle engine outputs stable torque, and meanwhile, emission of particulate matters is reduced. In addition, the application can effectively reduce the air-fuel ratio, improve the combustion stability, inhibit knocking and fire, reduce torque fluctuation among cycles and improve the running smoothness of the engine. In some embodiments, determining the Miller degree in a target cylinder of a Miller cycle engine at the current moment comprises obtaining an intake valve opening angle and an intake valve closing angle of the target cylinder under the current working cycle, determining the Miller degree in the target cylinder at the current moment based on a preset Miller degree calculation model, the intake valve opening angle and the intake valve closing angle, wherein the Miller degree calculation model is used for quantifying the Miller degree in the cylinder based on the intake valve opening and closing angle and structural parameters of the cylinder. According to the technical means, the Miller degree in the target cylinder at the current moment is calculated based on the opening and closing angle of the intake valve in the target cylinder at the current moment and the preset Miller degree calculation model, so that the actual effective compression ratio and the air inflow of the cylinder under the current cycle can be accurately reflected, the instantaneity and the accuracy of the Miller degree calculation are improved, accurate basis is provided for follow-up fuel injection parameters, air-fuel ratio and torque control, and therefore the combustion stability of the engine is improved, torque fluctuation is reduced, and running smoothness is improved. In some embodiments, the fuel injection parameters include a target rail pressure, the fuel injection control model is a first correction model, the fuel injection parameters of the target cylinder