Distributed fuel delivery system for alternative gaseous fuel applications

• US 8,706,383 B2
• Filed: 11/18/2010
• Issued: 04/22/2014
• Est. Priority Date: 02/15/2010
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Sauve, Marc, Avallone, Louis A., Kozole, Karl H.
• Primary Examiner(s): Kwon, John
• Application Number:
  US12/949,273
• Publication Number:
  US 20110202256A1
• Time in Patent Office: 1,251 Days
• Field of Search: 701103-105, 701/114, 701/115, 123/434, 123/436, 123/673, 123/674, 123/679, 123/690
• US Class Current: 701/105
• CPC Class Codes: F02D 41/0025 Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
• CPC Class Codes: F02D 41/1454 the characteristics being an oxygen content or concentration or the air-fuel ratio
• CPC Class Codes: F02D 41/1476 Biasing of the sensor
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: F02D 41/40 with means for controlling injection timing or duration
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A control system includes an engine control module that generates fuel injector command signals for fuel injectors of an engine and engine parameter signals that indicate operating characteristics of the engine. A fuel injector control module communicates with the engine control module via a network. The engine control module transmits the engine parameter signals to the fuel injector control module via the network. The fuel injector control module generates compensated fuel injector signals based on the fuel injector command signals and the engine parameter signals. The engine control module may generate fuel injector command signals for a gaseous fuel mode based on signals received from the fuel injector control module.

Claims

1. A control system comprising:

an engine control module that generates fuel injector command signals for fuel injectors of an engine and engine parameter signals that indicate operating characteristics of the engine; and

a fuel injector control module that communicates with the engine control module via a network,

wherein

the engine control module transmits the engine parameter signals to the fuel injector control module via the network,

the fuel injector control module generates compensated fuel injector signals based on the fuel injector command signals and the engine parameter signals,

the fuel injector control module generates at least one offset signal and transmits the at least one offset signal to the engine control module via the network, and

the engine control module receives information provided in the at least one offset signal and generates the fuel injector command signals based on the at least one offset signal.

2. The control system of claim 1, wherein:

the at least one offset signal comprises at least one of an oxygen bias offset signal, a fuel equivalence ratio offset signal, a fuel trim limit offset signal, a fuel injector minimum pulse offset signal, a fuel flow rate offset signal, and a fuel injector opening offset signal; and

the engine parameter signals comprise engine parameters sent from the engine control module to the fuel injector control module.

3. The control system of claim 1, wherein the engine control module comprises:

a first fuel source adaptation module that generates a first gain signal based on a first long term fuel correction multiplier and a first oxygen offset; and

a second fuel source adaptation module that generates a second gain signal based on a second long term fuel correction multiplier and a second oxygen offset.

4. The control system of claim 3, wherein:

the first long term fuel correction multiplier is generated based on calibration values stored in the engine control module; and

the second long term fuel correction multiplier is generated based on the calibration values stored in the engine control module and signals received from the fuel injector control module via the network.

5. The control system of claim 3, wherein:

the fuel injector control module generates a fuel mode signal that indicates one of a liquid fuel mode and a gaseous fuel mode;

the fuel injector control module transmits the fuel mode signal to the engine control module via the network;

the engine control module performs a first selection that includes selecting one of the first long term fuel correction multiplier and the second long term fuel correction multiplier based on the fuel mode signal;

the engine control module performs a second selection that includes selecting one of the first oxygen offset and the second oxygen offset based on the fuel mode signal; and

generates the fuel injector command signals based on the first selection and the second selection.

6. The control system of claim 5, wherein

the engine control module selects equivalence ratio offsets and injector flow and opening offsets based on the fuel mode signal;

and

generates the fuel injector command signals based on the first selection, the second selection, the equivalence ratio offsets and the injector flow and opening offsets.

7. The control system of claim 1, wherein:

the engine control module comprises memory that stores calibration values; and

the engine control module generates the fuel injector command signals based on the calibration values.

8. The control system of claim 1, wherein:

the engine control module and the fuel injector control module operate in a liquid fuel mode and a gaseous fuel mode;

the engine control module selects an injector flow rate, an offset and a minimum pulse width for a nominal fuel pressure and a nominal fuel temperature when in the gaseous fuel mode;

the engine control module generates the fuel injector command signals based on the injector flow rate, the offset and the minimum pulse width as updated based on an injector flow offset signal, an opening offset signal, and a minimum pulse width offset signal received from the fuel injector control module;

the fuel injector control module stores the nominal fuel pressure and the nominal fuel temperature;

the fuel injector control module determines a requested fuel mass for a gaseous fuel injector based on the fuel injector command signals and the nominal fuel pressure, the nominal fuel temperature and other engine parameters; and

wherein the fuel injector control module generates the compensated fuel injector signals based on the requested fuel mass and a detected fuel pressure and a detected fuel temperature.

9. The control system of claim 1, wherein the engine control module generates fuel injector command signals for a gaseous fuel mode based on signals received from the fuel injector control module.

10. The control system of claim 1, wherein the engine control module:

removes lost fuel mass and transient fuel mass from a calculated fuel mass to generate a resultant fuel mass; and

generates the fuel injector command signals based on the resultant fuel mass, a calibrated fuel flow, a calibrated injector amount of open time, a calibrated injector offset, a minimum pulse width, and offset signals from the fuel injector control module,

wherein the fuel injector control module does not remove lost fuel contributions and transient fuel contributions from the fuel injector command signals when generating compensated fuel injector command signals.

11. The control module of claim 1, wherein:

the fuel injector control module generates an equivalence ratio offset signal and a post oxygen sensor bias offset signal;

the fuel injector control module transmits the equivalence ratio offset signal and the post oxygen sensor bias offset signal to the engine control module via the network; and

the engine control module offsets engine fuel control parameters based on the equivalence ratio offset signal and the post oxygen sensor bias offset signal.

12. A control system comprising:

an engine control module that generates fuel injector command signals for fuel injectors of an engine and engine parameter signals that indicate operating characteristics of the engine; and

a fuel injector control module that communicates with the engine control module via a network,

wherein

the engine control module transmits the engine parameter signals to the fuel injector control module via the network,

the fuel injector control module generates compensated fuel injector signals based on the fuel injector command signals and the engine parameter signals, selects one of a liquid fuel mode and a gaseous fuel mode, and generates a fuel mode signal,

the engine control module and the fuel injector control module switch between the liquid fuel mode and the gaseous fuel mode based on a transition of the fuel mode signal between the liquid fuel mode and the gaseous fuel mode and within a predetermined period, wherein the switch starts with a predetermined cylinder, and

the engine control module adjusts fuel pulse calculations based on the fuel mode signal in the predetermined period and for a cylinder of the engine.

13. The control module of claim 12, wherein:

the fuel injector control module transmits the fuel mode signal to the engine control module via the network;

the fuel injector control module delays transitioning between the liquid fuel mode and the gaseous fuel mode for a predetermined number of engine cycles; and

the engine control module delays transitioning between the liquid fuel mode and the gaseous fuel mode for the predetermined number of engine cycles.

14. An engine control module comprising:

a first adaptation module that stores a first long term multiplier for a primary fuel;

a second adaptation module that stores a second long term multiplier for a secondary fuel;

a fuel mode module receives a fuel mode signal from a fuel injector control module via a network and enables one of (i) the first adaptation module and (ii) the second adaptation module based on the fuel mode signal;

a closed loop fuel module that generates a first gain signal based on the first long term multiplier when operating on the primary fuel and a second gain signal based on the second long term multiplier when operating on the secondary fuel; and

a fuel injection module that generates a fuel injector command signal based on one of the first gain signal and the second gain signal.

15. The engine control module of claim 14, further comprising:

a first calibration module that stores primary calibration data for the primary fuel; and

a second calibration module that stores secondary calibration data for the secondary fuel,

wherein the fuel injection module generates the fuel injector command signal based on the primary calibration data when operating on the primary fuel and based on the secondary calibration data when operating the secondary fuel.

16. The engine control module of claim 15, wherein:

the fuel mode module receives a secondary air/fuel ratio offset adjustment signal, a secondary oxygen sensor offset adjustment signal, a secondary fuel injector parameter adjustment signal, and a diagnostic limit adjustment signal from the fuel injector control module via the network; and

the fuel injection module generates the fuel injector command signal based on the secondary air/fuel ratio offset adjustment signal, the secondary oxygen sensor offset adjustment signal, the secondary fuel injector parameter adjustment signal and the diagnostic limit adjustment signal when operating on the secondary fuel.

17. The engine control module of claim 15, wherein:

the primary fuel is a gasoline-based fuel;

the secondary fuel is a gaseous fuel;

the primary calibration data is gasoline fuel calibration data; and

the secondary calibration data is gaseous fuel calibration data.

18. The engine control module of claim 15, wherein the primary calibration data and the secondary calibration data comprise respective fuel system trim diagnostic thresholds, stoichiometric air/fuel ratios, equivalence ratio biases, and post oxygen sensor biases.

19. The engine control module of claim 15, wherein the primary calibration data and the secondary calibration data comprise respective injector flow values, injector offsets, and injector minimum pulse widths, lost fuel values and transient fuel values.

20. The engine control module of claim 14, further comprising:

a diagnostic module that generates an output signal based on second fuel trim diagnostic threshold calibrations, and a second lean fuel trim limit offset and a second rich fuel trim limit offset received from the fuel injector control module via the network; and

a torque estimation module that controls a maximum output torque of the engine based on the torque limiting signal which may be generated based on signals received from the fuel injector control module by limiting air per cylinder of the engine during a startup of the engine and preheating of the secondary fuel.