Method for operating an internal combustion engine, in particular for a motor vehicle

• US 6,247,445 B1
• Filed: 03/05/1999
• Issued: 06/19/2001
• Est. Priority Date: 07/08/1997
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Langer, Winfried
• Primary Examiner(s): Dolinar, Andrew M.
• Application Number:
  US09/254,582
• Time in Patent Office: 837 Days
• Field of Search: 123/295, 123/305, 123/350, 123/690, 123/479, 701/107, 701/114, 731/19.A
• US Class Current: 123/305
• CPC Class Codes: F02D 2041/389 for injecting directly into the cylinder
• CPC Class Codes: F02D 2200/1004 Estimation of the output torque
• CPC Class Codes: F02D 2250/18 Control of the engine output torque
• CPC Class Codes: F02D 2250/26 by applying a torque limit
• CPC Class Codes: F02D 41/1497 With detection of the mechanical response of the engine
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F02D 41/3029 further comprising a homogeneous charge spark-ignited mode

Abstract

A method for operating an internal combustion engine, in particular of a motor vehicle, in which fuel is injected either in a first operating mode during a compression phase, or in a second operating mode during an intake phase, directly into a combustion chamber. In both operating modes, the fuel mass injected into the combustion chamber is controlled and/or regulated as a function, among other things, of a calculated reference torque to be delivered by the internal combustion engine. A true torque delivered by the internal combustion engine and a permissible torque are determined; and the true torque is compared to the permissible torque.

Claims

1. A method for operating an internal combustion engine, comprising the steps of:

in one of a first operating mode and a second operating mode, injecting a fuel mass directly into a combustion chamber, the first operating mode being during a compression phase, the second operating mode being during an intake phase;

calculating a reference torque to be provided by the internal combustion engine;

in the first and second operating modes, controlling the fuel mass injected into the combustion chamber as a function of the calculated reference torque;

determining an actual torque provided by the internal combustion engine, wherein the actual torque is determined as a function of at least one of the fuel mass which is combusted and a combusted oxygen mass;

determining a permissible torque; and

comparing the actual torque with the permissible torque.

2. The method according to claim 1, further comprising the step of:

starting a predetermined procedure if the actual torque is greater than the permissible torque.

3. The method according to claim 1, wherein the actual torque is determined as a function of the fuel mass which is combusted.

4. The method according to claim 1, wherein the actual torque is determined as a function of the combusted oxygen mass.

5. The method according to claim 4, wherein the combusted oxygen mass is determined as a function of an infed fresh air and oxygen which remains in an exhaust gas of the internal combustion engine.

6. The method according to claim 5, further comprising the steps of:

measuring the infed fresh air by an air mass sensor; and

measuring the oxygen remaining in the exhaust gas by a lambda sensor.

7. The method according to claim 4, wherein the combusted oxygen mass is determined as a function of a recirculation of an exhaust gas.

8. The method according to claim 1, wherein the permissible torque is determined as a function of a particular torque.

9. The method according to claim 8, further comprising the step of:

specifying the particular torque by a driver.

10. The method according to claim 9, wherein the permissible torque is determined as a function of a rotational speed of the internal combustion engine.

11. The method according to claim 10, further comprising the steps of:

measuring the particular torque by an accelerator pedal sensor; and

measuring the rotational speed by a rotational speed sensor.

12. The method according to claim 1, wherein the internal combustion engine is contained in a motor vehicle.

13. The method according to claim 1, wherein the fuel mass which is combusted is determined based on an air mass, a recirculated exhaust gas mass, a first air/fuel ratio and a second air/fuel ratio.

14. The method according to claim 1, wherein the fuel mass which is combusted (vK) is determined based on an air mass (mL), a recirculated exhaust gas mass (mAGR), a first air/fuel ratio (λ

), a second air/fuel ratio (λ

′

) and a constant (k), where;

15. The method according to claim 14, wherein k=14.8 for λ

=1.

16. An electrical arrangement for a control device of an internal combustion engine, comprising:

a storage device storing a program, the program being executed by a calculation device to perform the following;

in one of a first operating mode and a second operating mode, injecting a fuel mass directly into a combustion chamber, the first operating mode being during a compression phase, the second operating mode being during an intake phase,

calculating a reference torque to be provided by the internal combustion engine,

in the first and second operating modes, controlling the fuel mass injected into the combustion chamber as a function of the calculated reference torque,

determining an actual torque provided by the internal combustion engine, wherein the actual torque is determined as a function of at least one of the fuel mass which is combusted and a combusted oxygen mass,

determining a permissible torque, and

comparing the actual torque with the permissible torque.

17. The electrical arrangement according to claim 16, wherein the storage device includes a read-only memory device.

18. The electrical arrangement according to claim 16, wherein the internal combustion engine is contained in a motor vehicle.

19. The electrical arrangement according to claim 16, wherein the calculation device includes a microprocessor.

20. An internal combustion engine, comprising:

an injection valve injecting a fuel mass directly into a combustion chamber in one of a first operating mode and a second operating mode, the first operating mode being during a compression phase, the second operating mode being during an intake phase; and

a control device calculating a reference torque to be provided by the internal combustion engine, the control device controlling the fuel mass injected into the combustion chamber in the first and second operating modes as a function of the calculated reference torque,

wherein;

the control device determines an actual torque provided by the internal combustion engine and a permissible torque;

the actual torque is determined as a function of at least one of the fuel mass which is combusted and a combusted oxygen mass; and

the control device compares the actual torque with the permissible torque.

21. The internal combustion engine according to claim 20, further comprising:

an air mass sensor communicating with the control device; and

a lambda sensor communicating with the control device.

22. The internal combustion engine according to claim 20, further comprising:

an accelerator pedal sensor communicating with the control device; and

a rotation speed sensor communicating with the control device.

23. The internal combustion engine according to claim 20, wherein the internal combustion engine is contained in a motor vehicle.

24. A method for operating an internal combustion engine, comprising the steps of:

in one of a first operating mode and a second operating mode, injecting a fuel mass directly into a combustion chamber, the first operating mode being during a compression phase, the second operating mode being during an intake phase;

calculating a reference torque to be provided by the internal combustion engine;

in the first and second operating modes, controlling the fuel mass injected into the combustion chamber as a function of the calculated reference torque;

determining an actual torque provided by the internal combustion engine;

determining a permissible torque;

comparing the actual torque with the permissible torque; and

determining that a calculation of the reference torque is faulty based on at least one of a faulty control device, a faulty input variable for calculating the reference torque, a faulty sensor and a faulty software program of the control device;

wherein the actual torque is determined as a function of at least one of the fuel mass which is combusted and a combusted oxygen mass.

25. A method for operating an internal combustion engine, comprising the steps of:

in one of a first operating mode and a second operating mode, injecting a fuel mass directly into a combustion chamber, the first operating mode being during a compression phase, the second operating mode being during an intake phase;

calculating a reference torque to be provided by the internal combustion engine;

in the first and second operating modes, controlling the fuel mass injected into the combustion chamber as a function of the calculated reference torque;

determining an actual torque provided by the internal combustion engine;

determining a permissible torque;

comparing the actual torque with the permissible torque; and

determining that a calculation of the reference torque is faulty based on at least one of a faulty control device, a faulty input variable for calculating the reference torque, a faulty sensor and a faulty software program of the control device;

wherein the actual torque is determined as a function of the fuel mass which is combusted.

26. A method for operating an internal combustion engine, comprising the steps of:

in one of a first operating mode and a second operating mode, injecting a fuel mass directly into a combustion chamber, the first operating mode being during a compression phase, the second operating mode being during an intake phase;

calculating a reference torque to be provided by the internal combustion engine;

in the first and second operating modes, controlling the fuel mass injected into the combustion chamber as a finction of the calculated reference torque;

determining an actual torque provided by the internal combustion engine;

determining a permissible torque;

comparing the actual torque with the permissible torque; and

determining that a calculation of the reference torque is faulty based on at least one of a faulty control device, a faulty input variable for calculating the reference torque, a faulty sensor and a faulty software program of the control device;

wherein the actual torque is determined as a function of the combusted oxygen mass.

27. The method according to claim 26, wherein the combusted oxygen mass is determined as a function of an infed fresh air and oxygen which remains in an exhaust gas of the internal combustion engine.

28. The method according to claim 27, further comprising the steps of:

measuring the infed fresh air using an air mass sensor; and

measuring the oxygen remaining in the exhaust gas using a lambda sensor.

29. The method according to claim 26, wherein the combusted oxygen mass is determined as a function of a recirculation of an exhaust gas.

30. A method for operating an internal combustion engine, comprising the steps of:

in one of a first operating mode and a second operating mode, injecting a fuel mass directly into a combustion chamber, the first operating mode being during a compression phase, the second operating mode being during an intake phase;

calculating a reference torque to be provided by the internal combustion engine;

in the first and second operating modes, controlling the fuel mass injected into the combustion chamber as a function of the calculated reference torque;

determining an actual torque provided by the internal combustion engine;

determining a permissible torque;

comparing the actual torque with the permissible torque; and

determining that a calculation of the reference torque is faulty based on at least one of a faulty control device, a faulty input variable for calculating the reference torque, a faulty sensor and a faulty software program of the control device;

wherein the fuel mass which is combusted is determined based on an air mass, a recirculated exhaust gas mass, a first air/fuel ratio and a second air/fuel ratio.

31. A method for operating an internal combustion engine, comprising the steps of:

in one of a first operating mode and a second operating mode, injecting a fuel mass directly into a combustion chamber, the first operating mode being during a compression phase, the second operating mode being during an intake phase;

calculating a reference torque to be provided by the internal combustion engine;

in the first and second operating modes, controlling the fuel mass injected into the combustion chamber as a function of the calculated reference torque;

determining an actual torque provided by the internal combustion engine;

determining a permissible torque;

comparing the actual torque with the permissible torque; and

determining that a calculation of the reference torque is faulty based on at least one of a faulty control device, a faulty input variable for calculating the reference torque, a faulty sensor and a faulty software program of the control device;

wherein the fuel mass which is combusted (vK) is determined based on an air mass (mL), a recirculated exhaust gas mass (mAGR), a first air/fuel ratio (λ

), a second air/fuel ratio (λ

′

) and a constant (k), where;

32. The method according to claim 31, wherein k=14.8 for λ

=1.