System and Methods for Improved Efficiency Compression Ignition Internal Combustion Engine Control

• US 20120046853A1
• Filed: 08/18/2011
• Published: 02/23/2012
• Est. Priority Date: 08/20/2010
• Status: Abandoned Application

• Current Assignee: Tula Technology, Incorporated
• Original Assignee: Tula Technology, Incorporated
• Inventors: Silvestri, Chester J., Tripathi, Adya S., Sahandiesfanjani, Farzad
• Application Number:
  US13/213,061
• Publication Number:
  US 20120046853A1
• Time in Patent Office: Days
• US Class Current: 701/104
• CPC Class Codes: F02D 37/02 one of the functions being ignition
• CPC Class Codes: F02D 41/0087 Selective cylinder activation, i.e. partial cylinder operation deceleration cut-off F02D41/123
• CPC Class Codes: F02D 41/1402 Adaptive control
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: F02D 41/3011 according to or using specific or several modes of combustion

Abstract

The present invention relates to a compression ignition engine control system and methods for improving fuel efficiency. The system includes a fuel processor which receives instructions for a desired engine output and current operating conditions. The fuel processor generates fueling instructions for a plurality of cylinders. The fueling instructions include a low power skip fire mode of operation and a high power mode of operation. The instructions substantially regulate fuel delivery into to a first group of cylinders at or near optimal efficiency fuel levels during each of their respective working cycles. Likewise, the instructions may either substantially disable fuel injection into to a second grouping of cylinders or regulate fuel injection into to the second grouping of cylinders at an elevated high power fuel to air ratio. The fuel processor may include a synchronizer for synchronizing firing of the cylinders with the engine speed. Likewise, the fuel processor may include a sigma delta control circuit for generating a firing pattern that utilizes predictive adaptive control.

Claims

1. A method for improving efficiency of a compression ignition internal combustion engine having a plurality of cylinders capable of operating in a succession of combustion cycles by generating a non-uniform fueling profile to generate fueling efficiency gains, the method comprising:

receiving a request for a first desired engine output;

generating fuel injection instructions to generate the non-uniform fueling profile across the plurality of cylinders which will produce a power output from the compression ignition internal combustion engine which substantially conforms to the first desired engine output, wherein said generating step comprises;

substantially controlling the regulation of fuel flow to at least one of the plurality of cylinders at a substantially optimal efficiency fuel level during each of their respective working cycles, wherein the regulation of fuel flow to the at least one of the plurality of cylinders is determined by the generated fuel injection instructions, and wherein the optimal efficiency fuel level is determined from the ratio of fuel injected into the at least one cylinder to the air drawn into the at least one cylinder which substantially maximizes fuel efficiency; and

substantially controlling the regulation of fuel flow to at least one of the other of the plurality of cylinders at a higher fuel level, wherein the number of cylinders receiving the higher fuel level is dynamically determined to provide the first desired output for the engine.

2. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 1, further comprising:

receiving an updated request for a second desired engine output; and

substantially controlling the regulation of fuel flow to at least one of the plurality of cylinders at a second higher fuel level, wherein the second higher fuel level is dynamically determined to provide the second desired output for the engine.

3. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 1, further comprising:

determining a maximum number of the plurality of cylinders that can be operated all of the time at the optimal efficiency fuel level without exceeding the first desired output;

substantially controlling the regulation of fuel delivery to a first subset of cylinders of the plurality of cylinders at optimal efficiency fuel level during at least one of their respective working cycles, wherein the first subset of cylinders is limited to the maximum number of cylinders; and

substantially disabling fuel injection into a second subset of cylinders of the plurality of cylinders during at least one of their respective working cycles, wherein the first subset of cylinders plus the second subset of cylinders equals the plurality of cylinders.

4. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 3, further comprising receiving at least one current operating condition including at least one of engine speed, wheel speed, air intake manifold flux, slope the vehicle is on, and movement resistance.

5. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 4, wherein determining the maximum number of the plurality of cylinders that can be operated all of the time at the optimal efficiency fuel level without exceeding the first desired output includes referencing the at least one current operating condition.

6. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 4, further comprising synchronizing firing of the plurality of cylinders during their working cycles with the engine speed.

7. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 3, further comprising monitoring the desired output and adaptively changing the number of cylinders in operation and adaptively varying the fueling of the at least one of the first subset of cylinders in order to deliver the desired output in accordance with variations in the desired output.

8. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 1, wherein the compression ignition internal combustion engine is a diesel engine.

9. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 1, wherein the compression ignition internal combustion engine is a homogenous charge compression ignition engine.

10. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 1, wherein the first desired engine output may be determined using adaptive predictive control circuitry.

11. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 10, wherein a sigma delta controller is used in the generation of the fuel injection instructions.

12. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 10, wherein the predictive adaptive control circuitry is selected from the group consisting of:

a pulse width modulation controller, a least means square controller and a recursive least square controller.

13. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 10, wherein the predictive adaptive control circuitry includes feedback indicative of at least one of requested and actual working cycle firings.

14. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 13, wherein the generation of the fuel injection instructions is determined at least in part using predictive adaptive feedback control to provide the first desired engine output.

15. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 1, wherein air intake to the plurality of cylinders is constant over the succession of combustion cycles.

16. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 15, wherein fuel injection into each of the at least one of the plurality of cylinders is modulated to achieve the substantially optimal fuel to air ratio.

17. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 15, wherein fuel injection into each of the at least one of the plurality of cylinders is modulated to achieve a first and second variable fuel to air ratio.

18. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 1, wherein the fuel injection instructions are dynamically calculated during operation of the engine on a working cycle by working cycle basis to provide the first desired engine output.

19. A system for improving efficiency of a compression ignition internal combustion engine having a plurality of cylinders capable of operating in a succession of combustion cycles by generating a non-uniform fueling profile to generate fueling efficiency gains, the system comprising:

a fuel processor configured to perform the steps of;

receiving a request for a first desired engine output;

generating fuel injection instructions to generate the non-uniform fueling profile across the plurality of cylinders which will produce a power output from the compression ignition internal combustion engine which substantially conforms to the first desired engine output, wherein said generating step comprises;

substantially controlling the regulation of fuel flow to at least one of the plurality of cylinders at a substantially optimal efficiency fuel level during each of their respective working cycles, wherein the regulation of fuel flow to the at least one of the plurality of cylinders is determined by the generated fuel injection instructions, and wherein the optimal efficiency fuel level is determined by the ratio of fuel injected into the at least one cylinder to air drawn into the at least one cylinder which substantially maximizes fuel efficiency; and

substantially controlling the regulation of fuel flow to at least one of the other of the plurality of cylinders at a higher fuel level, wherein the number of cylinders receiving the higher fuel level is dynamically determined to provide the first desired output for the engine.

20. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 19, wherein the fuel processor is further configured to:

receive an updated request for a second desired engine output; and

substantially regulate fuel flow to at least one of the plurality of cylinders at a second higher fuel level, wherein the second higher fuel level is dynamically determined to provide the second desired output for the engine.

21. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 19, wherein the fuel processor is further configured to:

determine a maximum number of the plurality of cylinders that can be operated all of the time at the optimal efficiency fuel level without exceeding the first desired output;

substantially regulate fuel delivery to a first subset of cylinders of the plurality of cylinders at optimal efficiency fuel level during at least one of their respective working cycles, wherein the first subset of cylinders is limited to the maximum number of cylinders; and

substantially disable fuel injection into a second subset cylinders of the plurality of cylinders during at least one of their respective working cycles, wherein the first subset of cylinders plus the second subset of cylinders equals the plurality of cylinders.

22. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 21, wherein the fuel processor receives at least one current operating condition including at least one of engine speed, wheel speed, air intake manifold flux, slope the vehicle is on, and movement resistance.

23. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 22, wherein determining the maximum number of the plurality of cylinders that can be operated all of the time at the optimal efficiency fuel level without exceeding the first desired output includes referencing the at least one current operating condition.

24. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 22, wherein the fuel processor includes a synchronizer configured to synchronize firing of the plurality of cylinders during their working cycles with the engine speed.

25. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 21, wherein the fuel processor includes a sigma delta control circuit configured to monitor the desired output and adaptively changing the number of cylinders in operation and adaptively varying the fueling of the at least one of the first subset of cylinders in order to deliver the desired output in accordance with variations in the desired output.

26. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 19, wherein the compression ignition internal combustion engine is a diesel engine.

27. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 19, wherein the compression ignition internal combustion engine is a homogenous charge compression ignition engine.

28. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 25, wherein the fuel processor comprises an adaptive predictive control circuitry adapted to determine the first desired engine output.

29. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 28, wherein the fuel processor comprises a sigma delta controller used in the generation of the fuel injection instructions.

30. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 28, wherein the predictive adaptive control circuitry is selected from the group consisting of:

a pulse width modulation controller, a least means square controller and a recursive least square controller.

31. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 28, wherein the predictive adaptive control circuitry includes feedback indicative of at least one of requested and actual working cycle firings.

32. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 31, wherein the generation of the fuel injection instructions is determined at least in part using predictive adaptive feedback control to provide the first desired engine output.

33. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 19, wherein air intake to the plurality of cylinders is constant over the succession of combustion cycles.

34. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 33, wherein fuel injection into each of the at least one of the plurality of cylinders is modulated to achieve the substantially optimal fuel to air ratio.

35. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 33, wherein fuel injection into each of the at least one of the plurality of cylinders is modulated to achieve a first and second variable fuel to air ratio.

36. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 19, wherein the fuel injection instructions are dynamically calculated during operation of the engine on a working cycle by working cycle basis to provide the first desired engine output.

37. A method for improving efficiency of a compression ignition internal combustion engine having a plurality of cylinders capable of operating in a succession of combustion cycles by generating a non-uniform fueling profile to generate fueling efficiency gains, the method comprising:

receiving a request for a first desired engine output;

generating fuel injection instructions to generate the non-uniform fueling profile across the plurality of cylinders which will produce a power output from the compression ignition internal combustion engine which substantially conforms to the first desired engine output, wherein said generating step comprises;

substantially controlling the regulation of fuel flow to a first subset of the plurality of cylinders at a substantially optimal efficiency fuel level during at least one of their respective working cycles, wherein the regulation of fuel flow to the first subset of the plurality of cylinders is determined by the generated fuel injection instructions, and wherein the optimal efficiency fuel level is determined from the ratio of fuel injected into the at least one cylinder to air drawn into the at least one cylinder which substantially maximizes fuel efficiency; and

substantially disabling fuel injection into to a second subset of the plurality of cylinders while the compression ignition internal combustion engine is in a first operational state corresponding to the first desired engine output, wherein the ratio of cylinders in the first subset of cylinders and the second subset of cylinders corresponds to the generated fuel injection instructions, and wherein the first subset of cylinders plus the second subset of cylinders equals the plurality of cylinders.

38. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 37, further comprising:

receiving an updated request for a second desired engine output; and

substantially controlling the regulation of fuel flow to at least one of the other of the plurality of cylinders at a higher fuel level, wherein the higher fuel level is dynamically determined to provide the second desired output for the engine.

39. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 37, further comprising receiving at least one current operating condition including at least one of engine speed, wheel speed, air intake manifold flux, slope the vehicle is on, and movement resistance.

40. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 39, wherein the generating fuel injection instructions includes referencing the at least one current operating condition.

41. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 39, further comprising synchronizing firing of the plurality of cylinders during their working cycles with the engine speed.

42. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 37, further comprising:

monitoring the desired output and adaptively changing the number of cylinders in operation and adaptively varying the fueling of the at least one of the first subset of cylinders in order to deliver the desired output in accordance with variations in the desired output.

43. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 37, wherein the compression ignition internal combustion engine is a diesel engine.

44. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 37, wherein the compression ignition internal combustion engine is a homogenous charge compression ignition engine.

45. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 37, wherein the first desired engine output may be determined using adaptive predictive control circuitry.

46. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 45, wherein a sigma delta controller is used in the generation of the fuel injection instructions.

47. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 45, wherein the predictive adaptive control circuitry is selected from the group consisting of:

a pulse width modulation controller, a least means square controller and a recursive least square controller.

48. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 45, wherein the predictive adaptive control circuitry includes feedback indicative of at least one of requested and actual working cycle firings.

49. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 48, wherein the generation of the fuel injection instructions is determined at least in part using predictive adaptive feedback control to provide the first desired engine output.

50. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 37, wherein air intake to the plurality of cylinders is constant over the succession of combustion cycles.

51. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 50, wherein fuel injection into each of the at least one of the plurality of cylinders is modulated to achieve the substantially optimal fuel to air ratio.

52. The method for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 37, wherein the fuel injection instructions are dynamically calculated during operation of the engine on a working cycle by working cycle basis to provide the first desired engine output.

53. A system for improving efficiency of a compression ignition internal combustion engine having a plurality of cylinders capable of operating in a succession of combustion cycles by generating a non-uniform fueling profile to generate fueling efficiency gains, the system comprising:

a fuel processor configured to perform the steps of;

receiving a request for a first desired engine output;

generating fuel injection instructions to generate the non-uniform fueling profile across the plurality of cylinders which will produce a power output from the compression ignition internal combustion engine which substantially conforms to the first desired engine output, wherein said generating step comprises;

substantially controlling the regulation of fuel flow to a first subset of the plurality of cylinders at a substantially optimal efficiency fuel level during at least one of their respective working cycles, wherein the regulation of fuel flow to the first subset of the plurality of cylinders is determined by the generated fuel injection instructions, and wherein the optimal efficiency fuel level is determined from the ratio of fuel injected into the at least one cylinder to air drawn into the at least one cylinder which substantially maximizes fuel efficiency; and

substantially disabling fuel injection into to a second subset of the plurality of cylinders while the compression ignition internal combustion engine is in a first operational state corresponding to the first desired engine output, wherein the ratio of cylinders in the first subset of cylinders and the second subset of cylinders corresponds to the generated fuel injection instructions, and wherein the first subset of cylinders plus the second subset of cylinders equals the plurality of cylinders.

54. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 53, wherein the fuel processor is further configured to:

receive an updated request for a second desired engine output; and

substantially regulate fuel flow to at least one of the other of the plurality of cylinders at a higher fuel level, wherein the higher fuel level is dynamically determined to provide the second desired output for the engine.

55. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 53, wherein the fuel processor is further configured to receive at least one current operating condition including at least one of engine speed, wheel speed, air intake manifold flux, slope the vehicle is on, and movement resistance.

56. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 55, wherein the generating fuel injection instructions includes referencing the at least one current operating condition.

57. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 55, wherein the fuel processor is further configured to synchronize firing of the plurality of cylinders during their working cycles with the engine speed.

58. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 53, wherein the fuel processor includes a sigma delta control circuit configured to monitor the desired output and adaptively changing the number of cylinders in operation and adaptively varying the fueling of the at least one of the first subset of cylinders in order to deliver the desired output in accordance with variations in the desired output.

59. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 53, wherein the compression ignition internal combustion engine is a diesel engine.

60. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 53, wherein the compression ignition internal combustion engine is a homogenous charge compression ignition engine.

61. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 53, wherein the fuel processor comprises an adaptive predictive control circuitry adapted to determine the first desired engine output.

62. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 61, wherein the fuel processor comprises a sigma delta controller used in the generation of the fuel injection instructions.

63. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 61, wherein the predictive adaptive control circuitry is selected from the group consisting of:

a pulse width modulation controller, a least means square controller and a recursive least square controller.

64. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 61, wherein the predictive adaptive control circuitry includes feedback indicative of at least one of requested and actual working cycle firings.

65. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 64, wherein the generation of the fuel injection instructions is determined at least in part using predictive adaptive feedback control to provide the first desired engine output.

66. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 53, wherein air intake to the plurality of cylinders is constant over the succession of combustion cycles.

67. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 66, wherein fuel injection into each of the at least one of the plurality of cylinders is modulated to achieve the substantially optimal fuel to air ratio.

68. The system for improving the efficiency of the compression ignition internal combustion engine, as recited in claim 53, wherein the fuel injection instructions are dynamically calculated during operation of the engine on a working cycle by working cycle basis to provide the first desired engine output.

69. A method for improving efficiency of a compression ignition internal combustion engine having a plurality of cylinders capable of operating in a succession of combustion cycles by generating a non-uniform fueling profile to generate fueling efficiency gains, the method comprising:

receiving a request for a first desired engine output;

generating fuel injection instructions to generate the non-uniform fueling profile across the plurality of cylinders which will produce a power output from the compression ignition internal combustion engine which substantially conforms to the first desired engine output, wherein said generating step comprises;

comparing the first desired engine output to the power output provided by the compression ignition internal combustion engine operating with all of the plurality of cylinders at a substantially optimal efficiency fuel level during every working cycle, wherein if the first desired engine output is less than power output provided by the compression ignition internal combustion engine operating with all of the plurality of cylinders at a substantially optimal efficiency fuel level during every working cycle then;

substantially controlling the regulation of fuel flow to a first subset of the plurality of cylinders at a substantially optimal efficiency fuel level during each of their respective working cycles, wherein the regulation of fuel flow to the first subset of the plurality of cylinders is determined by the generated fuel injection instructions, and wherein the optimal efficiency fuel level is determined from the ratio of fuel injected into the at least one cylinder to air drawn into the at least one cylinder which substantially maximizes fuel efficiency; and

substantially disabling fuel injection into to a second subset of the plurality of cylinders during each of their respective working cycles while the compression ignition internal combustion engine is in a first operational state corresponding to the first desired engine output, wherein the ratio of cylinders in the first subset of cylinders and the second subset of cylinders corresponds to the generated fuel injection instructions;

else;

substantially controlling the regulation of fuel flow to at least one of the plurality of cylinders at the substantially optimal efficiency fuel level during each of their respective working cycles, wherein the regulation of fuel flow to the at least one of the plurality of cylinders is determined by the generated fuel injection instructions; and

substantially controlling the regulation of fuel flow to at least one of the other of the plurality of cylinders at a higher fuel level, wherein the higher fuel level is dynamically determined to provide the first desired output for the engine.