FUEL INJECTION AND COMBUSTION FAULT DIAGNOSTICS USING CYLINDER PRESSURE SENSOR

• US 20100299051A1
• Filed: 05/19/2009
• Published: 11/25/2010
• Est. Priority Date: 05/19/2009
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Haskara, Ibrahim, Wang, Yue-Yun, Matekunas, Frederic Anton, Battiston, Paul Anthony, Kweon, Chol-Bum M.
• Granted Patent: US 8,229,655 B2
• Time in Patent Office: Days
• US Class Current: 701/111
• CPC Class Codes: F02D 2041/288 for performing a transformation into the frequency domain, e.g. Fourier transformation
• CPC Class Codes: F02D 35/023 by determining the cylinder pressure
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/1498 measuring engine roughness
• 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: G05B 23/0235 based on a comparison with predetermined threshold or range, e.g. "classical methods", carried out during normal operation; threshold adaptation or choice; when or how to compare with the threshold
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

Systems and methods useful for detecting a combustion fault in a combustion engine include determining cylinder power density values for cylinders present on the engine during its operation and determining cylinder imbalance parameters for the cylinders, based on the cylinder power density values. The cylinder imbalance parameters are compared with a provided diagnostic threshold value.

Claims

1. Method useful for detecting a combustion fault in a combustion engine, comprising:

determining cylinder power density values for cylinders present on said engine during its operation;

determining cylinder imbalance parameters for said cylinders, based on said cylinder power density values;

providing a diagnostic threshold value;

comparing said cylinder imbalance parameters with said diagnostic threshold value.

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

indicating a combustion fault, when at least one cylinder imbalance parameter has a value which exceeds said diagnostic threshold value.

3. The method according to claim 2, wherein said combustion fault is a combustion fault that occurred in a single engine cylinder.

4. The method according to claim 2 wherein said engine is disposed in a motorized vehicle, and said indicating comprises setting a diagnostic code in an on-board diagnostic system.

5. The method according to claim 1 wherein said cylinder power density values are determined based on the output of a sensor selected from the group consisting of:

pressure sensors and thermal sensors.

6. The method according to claim 1 wherein said cylinder power density values are determined using a pressure ratio in a time domain.

7. The method according to claim 1 wherein said cylinder power density values are determined using a pressure ratio in a frequency domain.

8. The method according to claim 1 wherein said cylinder power density values are determined by first substantially determining individual cylinder heat release and subsequently substantially equating cylinder power density to said cylinder heat release.

9. The method according to claim 2 wherein said engine is disposed in a motorized vehicle and wherein at least one of said cylinder power density values, said cylinder imbalance parameters, and said combustion fault are conveyed wirelessly to a remote monitoring station.

10. System for detecting a combustion fault in an operating combustion engine, comprising:

an internal combustion engine having a plurality of cylinders;

at least one sensor disposed in effective sensing proximity to said engine sufficient to generate an output responsive to an operational characteristic of said engine during its operation; and

a controller configured to

receive the output from said at least one sensor as an input,

calculate cylinder power density values for the cylinders based on the output of said at least one sensor,

determine cylinder power imbalance parameters based on said cylinder power density values, and

compare said cylinder imbalance parameters to a predetermined diagnostic threshold.

11. The system according to claim 10 wherein said operational characteristic is a cylinder pressure.

12. The system according to claim 10 wherein said cylinder power density values are determined using a cylinder pressure ratio in a time domain.

13. The system according to claim 10 wherein said cylinder power density values are determined using a cylinder pressure ratio in a frequency domain.

14. The system according to claim 10 wherein said cylinder power density values are determined by first substantially determining individual cylinder heat release and subsequently substantially equating cylinder power density to said cylinder heat release.

15. The system according to claim 10, said controller further configured to indicate a combustion fault when a cylinder imbalance parameter differs from said diagnostic threshold by a predetermined amount.

16. The system according to claim 15, said controller being further configured to set a diagnostic code in a diagnostic system associated with operation of said engine.

17. The system according to claim 10, further comprising a wireless transmitter configured to receive information from said controller and transmit said information wirelessly to a remote receiving station.