Robust multi-criteria MBT timing estimation using ionization signal

• US 7,086,382 B2
• Filed: 06/11/2003
• Issued: 08/08/2006
• Est. Priority Date: 11/01/2002
• Status: Expired due to Term

• Current Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Original Assignee: Visteon Global Technologies Incorporated (Visteon Corporation)
• Inventors: Daniels, Chao F., Zhu, Guoming G.
• Primary Examiner(s): Wolfe, Willis R.
• Assistant Examiner(s): Hoang, Johnny H.
• Application Number:
  US10/458,715
• Publication Number:
  US 20040084020A1
• Time in Patent Office: 1,154 Days
• Field of Search: 123/406.23, 123/406.21, 123/406.19, 123/406.44, 123/406.48, 123/406.59, 701102-111, 731/16, 731/172, 731/173, 731/181
• US Class Current: 123/406.23
• CPC Class Codes: F01N 2430/00 Influencing exhaust purification, e.g. starting of catalytic reaction, filter regeneration, or the like, by controlling engine operating characteristics
• CPC Class Codes: F01N 3/2006 Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235
• CPC Class Codes: F02D 2041/141 using a feed-forward control element
• CPC Class Codes: F02D 2041/285 the sensor having a signal processing unit external to the engine control unit
• CPC Class Codes: F02D 2200/1015 Engines misfires
• CPC Class Codes: F02D 2250/18 Control of the engine output torque
• CPC Class Codes: F02D 35/021 using an ionic current sensor
• CPC Class Codes: F02D 35/023 by determining the cylinder pressure
• CPC Class Codes: F02D 35/027 using knock sensors
• CPC Class Codes: F02D 41/005 according to engine operating conditions
• CPC Class Codes: F02D 41/0255 to accelerate the warming-up of the exhaust gas treating apparatus at engine start
• CPC Class Codes: F02D 41/1408 Dithering techniques
• CPC Class Codes: F02D 41/1482 Integrator, i.e. variable slope
• 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 41/2454 Learning of the air-fuel ratio control
• CPC Class Codes: F02M 26/01 Internal exhaust gas recirculation, i.e. wherein the residual exhaust gases are trapped in the cylinder or pushed back from the intake or the exhaust manifold into the combustion chamber without the use of additional passages
• CPC Class Codes: F02P 17/02 Checking or adjusting ignition timing
• CPC Class Codes: F02P 17/10 Measuring dwell or antidwell time
• CPC Class Codes: F02P 17/12 Testing characteristics of the spark, ignition voltage or current testing of sparking plugs H01T13/60
• CPC Class Codes: F02P 2017/125 Measuring ionisation of combustion gas, e.g. by using ignition circuits
• CPC Class Codes: F02P 2017/128 : for knock detection
• CPC Class Codes: F02P 3/045 : for control of the dwell or anti dwell time
• CPC Class Codes: F02P 3/0453 : Opening or closing the primary coil circuit with semiconductor devices
• CPC Class Codes: F02P 3/051 : Opening or closing the primary coil circuit with semiconductor devices
• CPC Class Codes: F02P 5/1506 : with particular means during starting
• CPC Class Codes: F02P 5/1514 : with means for optimising the use of registers or of memories, e.g. interpolation
• CPC Class Codes: F02P 5/152 : dependent on pinking detecting or indicating knocks in internal-combustion engines G01L23/22
• CPC Class Codes: F02P 5/1523 : with particular laws of return to advance, e.g. step by step, differing from the laws of retard
• CPC Class Codes: F02P 5/1526 : with means for taking into account incorrect functioning of the pinking sensor or of the electrical means
• CPC Class Codes: Y02T 10/12 : Improving ICE efficiencies
• CPC Class Codes: Y02T 10/40 : Engine management systems

Abstract

This feature of the present invention is a robust multi-criteria minimum timing for the best torque (MBT) timing estimation method and apparatus utilizing different ionization signal waveforms that are generated under different engine operating conditions. This feature of the present invention determines and combines multiple MBT timing criteria to increase the reliability and robustness of MBT timing estimation based upon spark plug ionization signal waveforms. In a preferred embodiment, the present invention combines MBT timing estimation criteria comprising a maximum flame acceleration location, a 50% burn location, and a second peak location.

Claims

1. A method of estimating minimum timing for the best torque timing comprising using an ionization signal to calculate the minimum timing for the best torque timing, wherein said step of using an ionization signal to calculate the minimum timing for the best torque timing comprises combining one or more of a maximum flame acceleration point, a maximum heat release location and a second peak location.

2. The method of estimating minimum timing for the best torque timing according to claim 1 wherein said maximum flame acceleration point correlates to Top Dead Center, said maximum heat release location correlates to a 50% mass fraction burn location and said second peak location correlates to a peak pressure location.

3. The method of estimating minimum timing for the best torque timing according to claim 1 wherein said maximum flame acceleration point, said maximum heat release location and said second peak location are determined based on said ionization signal.

4. The method of estimating minimum timing for the best torque timing according to claim 1 wherein maximum flame acceleration point, said maximum heat release location and said second peak location are determined based on said ionization signal and a pressure signal.

5. The method of estimating minimum timing for the best torque timing according to claim 1 wherein said minimum timing for the best torque timing criteria comprises a maximum flame acceleration location.

6. The method of estimating minimum timing for the best torque timing according to claim 1 wherein said step of combining one or more of a maximum flame acceleration point, a maximum heat release location and a second peak location criteria comprises the step of combining a maximum heat release location and a second peak location.

7. The method of estimating minimum timing for the best torque timing according to claim 1 said step of combining minimum timing for the best torque timing criteria comprises:

determining what case an ionization signal waveform fits; and

calculating minimum timing for the best torque timing.

8. The method according to claim 1 wherein said step of combining a maximum flame acceleration location, a maximum heat release location, and a second peak location comprises the steps of:

creating a first sum by subtracting a 50% bum location from said maximum heat release location;

creating a second sum by subtracting a peak cylinder pressure location from said second peak location;

creating a third sum by adding said first sum, said second sum and said maximum flame acceleration location; and

dividing said third sum by three.

9. The method according to claim 6 wherein said step or combining a maximum heat release location and a second peak location comprises the steps of:

creating a first sum by subtracting a 50% burn location from said maximum heat release location;

creating a second sum by subtracting a peak cylinder pressure location from said second peak location;

creating a third sum by adding said first sum and said second sum; and

dividing said third sum by two.

10. The method of estimating minimum timing for the best torque timing according to claim 1 wherein said step of combining one or more of a maximum flame acceleration location, a maximum heat release location, and a second peak location comprises the steps of:

creating a first sum by subtracting a 50% burn location from a maximum heat release location;

creating a second sum by subtracting a peak cylinder pressure location from a second peak location;

creating a third sum by adding said first sum, said second sum and a maximum flame acceleration location; and

dividing said third sum by three.

11. A minimum timing for best torque estimator, comprising:

a controller;

memory operably connected to said controller;

software stored in said memory, said software comprises instructions that combine one or more of a maximum flame acceleration point, a maximum heat release location and a second peak location in order to estimate said minimum timing for best torque; and

an ionization detection unit operably connected to said controller.

12. The minimum timing for best torque estimator according to claim 11 further comprising a lookup table storing timing criteria and operably connected to said controller.

13. The minimum timing for best torque estimator according to claim 11 wherein said software further comprises:

instructions to determine what case an ionization signal waveform fits; and

instructions to calculate minimum timing for best torque timing.

14. The minimum timing for best torque estimator according to claim 11 wherein said software further comprises instructions which correlate a spark plug ionization signal to a cylinder pressure signal.

15. The minimum timing for best torque estimator according to claim 11 wherein said instructions that combine one or more of a maximum flame acceleration point, a maximum heat release location and a second peak location comprise:

creating a first sum by subtracting a 50% burn location from said maximum heat release location;

creating a second sum by subtracting a peak cylinder pressure location from said second peak location;

creating a third sum by adding said first sum, said second sum and said maximum flame acceleration location; and

dividing said third sum by three.

16. The minimum timing for best torque estimator according to claim 11 wherein said instructions that combine one or more of a maximum flame acceleration point, a maximum heat release location and a second peak location comprise:

creating a first sum by subtracting a 50% burn location from said maximum heat release location;

creating a second sum by subtracting a peak cylinder pressure location from said second peak location;

creating a third sum by adding said first sum and said second sum; and

dividing said third sum by two.

17. The minimum timing for best torque estimator according to claim 11 wherein said instructions that combine one or more of a maximum flame acceleration point, a maximum heat release location and a second peak location comprise:

creating a first sum by subtracting a 50% burn location from said maximum heat release location;

creating a second sum by subtracting a peak cylinder pressure location from said second peak location;

creating a third sum by adding said first sum, said second sum and said maximum flame acceleration location; and

dividing said third sum by three.