Method and computer program for operating an internal combustion engine, and control unit

• US 8,275,534 B2
• Filed: 12/18/2009
• Issued: 09/25/2012
• Est. Priority Date: 02/27/2009
• Status: Active Grant

• Current Assignee: Dr Ing hc F Porsche AG (Volkswagen AG)
• Original Assignee: Dr Ing hc F Porsche AG (Volkswagen AG)
• Inventors: Berr, Tobias Maria
• Primary Examiner(s): Cronin, Stephen K
• Assistant Examiner(s): Castro, Arnold
• Application Number:
  US12/641,767
• Publication Number:
  US 20100222983A1
• Time in Patent Office: 1,012 Days
• Field of Search: 701/29, 701/35, 701/102, 701/112, 701/113, 701/114, 123/179.3, 123/179.4
• US Class Current: 701/102
• CPC Class Codes: F02N 11/0814 comprising means for controlling automatic idle-start-stop
• CPC Class Codes: F02N 11/0818 Conditions for starting or stopping the engine or for deactivating the idle-start-stop mode
• CPC Class Codes: F02N 11/108 for diagnosis of the starter or its components
• CPC Class Codes: F02N 2300/30 characterised by the use of digital means
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A method makes it possible to measure and evaluate the efficiency of a start-stop system of a vehicle having an internal combustion engine, and on the basis of the measurement, to optimize the efficiency in a vehicle-specific fashion or with regard to the driving behavior of the driver.

Claims

1. A method of operating an internal combustion engine of a motor vehicle, the method which comprises:

automatically starting the internal combustion engine in dependence on at least one activation condition and/or automatically deactivating the internal combustion engine in dependence on at least one deactivation condition;

measuring the at least one activation condition and/or the at least one deactivation condition while the motor vehicle is at a standstill; and

storing a presence of the activation conditions and/or deactivation conditions in a memory and evaluating the presence of the activation conditions and/or deactivation conditions in order to diagnose a control of the internal combustion engine;

starting a first time counter when the vehicle comes to a standstill, and stopping the first time counter when the vehicle starts moving; and

prohibiting a deactivation of the internal combustion engine if a value of the first time counter is higher than a predefined threshold value.

2. The method according to claim 1, which comprises querying a first group of conditions for a deactivation stop of the internal combustion engine and incrementing a first counter by a value if all conditions of the first group of conditions are met.

3. The method according to claim 2, which comprises querying a second group of conditions for a deactivation of the internal combustion engine, incrementing a second counter by a value if all the conditions of the second group of conditions are met, and initiating a deactivation of the internal combustion engine.

4. The method according to claim 3, which comprises starting a second time counter when the internal combustion engine is deactivated, and stopping the second time counter when the internal combustion engine is re-activated.

5. The method according to claim 1, which comprises storing in the memory a cause for prohibiting the deactivation of the internal combustion engine together with a time indication.

6. The method according to claim 1, which comprises automatically activating the internal combustion engine if at least one activation condition is present, and storing a cause for the presence of the at least one activation condition in memory together with a time indication.

7. The method according to claim 4, which comprises forming a ratio from a value of the first time counter and a value of the second time counter.

8. The method according to claim 3, which comprises forming a ratio from a value of the first counter and a value of the second counter.

9. The method according to claim 1, which comprises carrying out the method for each driving cycle and/or over an entire operating duration of the vehicle.

10. The method according to claim 1, which comprises forming further conditions in dependence on one or more operating variables of the internal combustion engine and/or of a motor vehicle containing the internal combustion engine and/or of a system of the motor vehicle or of ambient conditions.

11. The method according to claim 10, which comprises selecting ambient conditions from the group consisting of a temperature, an air pressure, and a geodetic height.