Method, apparatus, signals and media, for selecting operating conditions of a genset

• US 8,346,416 B2
• Filed: 06/26/2007
• Issued: 01/01/2013
• Est. Priority Date: 06/26/2006
• Status: Active Grant

• Current Assignee: GE Hybrid Technologies, LLC
• Original Assignee: Azure Dynamics Incorporated
• Inventors: Liu, Wei, Bouchon, Nicolas Louis
• Primary Examiner(s): Tran, Dalena
• Assistant Examiner(s): Figueroa, Jamie
• Application Number:
  US11/821,855
• Publication Number:
  US 20080122228A1
• Time in Patent Office: 2,016 Days
• Field of Search: 701/22, 701/99, 290/40.R, 290/40.A, 290/40.B, 290/40.C, 903/902, 903/903, 903/905, 903/906, 180/65.1, 180/65.21, 180/65.28, 180/65.285, 700/287
• US Class Current: 701/22
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 1/02 to electric heating circuits
• CPC Class Codes: B60L 15/2045 for optimising the use of energy
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 3/0023 Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train
• CPC Class Codes: B60L 50/10 using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines
• CPC Class Codes: B60L 50/30 using propulsion power stored mechanically, e.g. in fly-wheels
• CPC Class Codes: B60L 50/40 using propulsion power supplied by capacitors
• CPC Class Codes: B60L 50/62 charged by low-power generators primarily intended to support the batteries, e.g. range extenders
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/24 including control of energy storage means
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 20/11 using model predictive control [MPC] strategies, i.e. control methods based on models predicting performance utilising navigation and traffic information in the control strategy B60W20/12
• CPC Class Codes: B60W 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 20/16 for reducing engine exhaust emissions
• CPC Class Codes: B60W 2510/06 : Combustion engines, Gas turbines
• CPC Class Codes: B60W 2556/10 : Historical data
• CPC Class Codes: F01N 11/00 : Monitoring or diagnostic devices for exhaust-gas treatment apparatus , e.g. for catalytic activity safety, indicating or supervising devices for internal combustion engines F02B77/08; testing of machines G01M13/00
• CPC Class Codes: G01F 13/00 : Apparatus for measuring by volume and delivering fluids or fluent solid materials, not provided for in the preceding groups
• CPC Class Codes: G01N 19/00 : Investigating materials by mechanical methods G01N3/00 - G01N17/00 take precedence
• CPC Class Codes: G06F 15/00 : Digital computers in general details G06F1/00 – G06F13/00; Data processing equipment in general
• CPC Class Codes: H02P 9/04 : Control effected upon non-electric prime mover and dependent upon electric output value of the generator
• CPC Class Codes: Y02T 10/40 : Engine management systems
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility
• CPC Class Codes: Y10S 903/902 : Prime movers comprising electrical and internal combustion motors
• CPC Class Codes: Y10S 903/903 : having energy storing means, e.g. battery, capacitor
• CPC Class Codes: Y10S 903/905 : Combustion engine
• CPC Class Codes: Y10S 903/906 : Motor or generator
• CPC Class Codes: Y10S 903/93 : Conjoint control of different elements

Abstract

A method and apparatus for selecting optimal operating conditions of a genset is disclosed. The genset includes an engine coupled to an electrical power generator, the genset having a plurality of operating points each including an engine speed value and a generator electrical power output value, and having a plurality of cost values associated with operating the genset at respective operating points. The method involves selecting a set of operating points from the plurality of operating points such that a sum of cost values associated with operating points in the set is minimized and such that the engine speed and generator electrical power output values of the operating points in the set increase or decrease monotonically.

Claims

1. A method for selecting operating conditions of a genset, the genset comprising an engine coupled to an electrical power generator, the genset having a plurality of operating points each comprising an engine speed value and a generator electrical power output value, and having a plurality of cost values associated with operating the genset at respective operating points, the method comprising:

selecting a set of operating points from the plurality of operating points such that a sum of cost values associated with operating points in said set is minimized and such that the engine speed values of the operating points in said set increase or decrease monotonically as a function of the generator electrical power output values of the operating points in said set.

2. The method of claim 1 further comprising assigning a weight to each of the power output values such that cost values corresponding to more frequently demanded power outputs values are assigned a greater weight in said sum of cost values than cost values corresponding to less frequently demanded electrical power output values.

3. The method of claim 2 wherein assigning said weight comprises assigning greater weight to electrical power output values proximate a midpoint of a range of power outputs that the generator is capable of supplying.

4. The method of claim 2 further comprising generating a record of received demands for power outputs during operation of the genset over a period of time, and wherein assigning said weights comprises assigning greater weight to more frequently used power output values.

5. The method of claim 4 wherein generating said record comprises generating said record and updating said weights while operating the genset and wherein selecting further comprises selecting a new set of operating points when said weights have been updated.

6. The method of claim 1 wherein selecting comprises:

successively applying a dynamic programming algorithm to select sets of operating points at successive power output values within a range of power outputs the generator is capable of supplying; and

selecting a set of operating points corresponding to a last power output value in said range as said set of operating points for said genset.

7. The method of claim 6 wherein applying said dynamic programming algorithm comprises:

producing a first plurality of sums of cost values at a first power output value;

memoizing a result of at least one of said first plurality of said sums; and

using at least some of said memoized results for producing a further sum of cost values at a subsequent power output value.

8. The method of claim 7 wherein selecting comprises locating a minimum cost value at each power output value and wherein successively applying said dynamic programming algorithm comprises first producing said sums of cost values corresponding to said minimum cost value at each successive power output value.

9. The method of claim 8 wherein locating said minimum cost value comprises locating an operating point corresponding to said minimum cost value using a golden section search technique.

10. The method of claim 1 further comprising receiving a demand to supply power at a demanded power output value and operating the genset at an operating point in said set of operating points corresponding to said demanded power output value.

11. The method of claim 10 wherein the genset is used to generate electrical energy for use in a hybrid vehicle and wherein receiving said demand comprises receiving a demand to supply power to at least one of a drive motor, a charger operable to charge a storage element, and an accessory associated with the hybrid vehicle.

12. The method of claim 11 wherein receiving said demand to supply power to said charger comprises receiving a demand to supply power to said charger while said hybrid electric vehicle remains stationary.

13. The method of claim 11 wherein receiving said demand to supply power to said drive motor comprises receiving a drive signal from an operator foot pedal representing a desired drive power to be supplied by said drive motor to wheels of said hybrid vehicle.

14. The method of claim 13 wherein said storage element is operable to supply at least a first portion of said desired drive power, and wherein receiving said demand comprises receiving a demand for a second portion of said desired drive power.

15. The method of claim 13 wherein receiving said demand to supply power to said charger comprises receiving a charge signal from a storage element controller, said charge signal being produced in response to a state of charge associated with said storage element.

16. The method of claim 1 further comprising receiving a plurality of cost values.

17. The method of claim 16 further comprising selecting a new set of operating points in response to receiving said plurality of cost values.

18. The method of claim 1 wherein selecting comprises selecting said set of genset operating points prior to operating said genset.

19. An apparatus for selecting operating conditions of a genset, the genset comprising an engine coupled to an electrical power generator, the genset having a plurality of operating points each comprising an engine speed value and a generator electrical power output value, and having a plurality of cost values associated with operating the genset at respective operating points, the apparatus comprising:

means for selecting a set of operating points from the plurality of operating points such that a sum of cost values associated with operating points in said set is minimized and such that the engine speed values of the operating points in said set increase or decrease monotonically as a function of the generator electrical power output values of the operating points in said set.

20. The apparatus of claim 19 further comprising means for assigning a weight to each of the power output values such that cost values corresponding to more frequently demanded power output values are assigned a greater weight in said sum of cost values than cost values corresponding to less frequently demanded electrical power output values.

21. The apparatus of claim 20 wherein said means for assigning said weight comprises means for assigning greater weight to electrical power output values proximate a midpoint of a range of power outputs that the generator is capable of supplying.

22. The apparatus of claim 20 further comprising means for generating a record of received demands for power outputs during operation of the genset over a period of time, and wherein said means for assigning said weights comprises means for assigning greater weight to more frequently used power output values.

23. The apparatus of claim 22 wherein said means for generating said record comprises means for updating said weights while operating the genset and wherein said means for selecting is operably configured to select a new set of operating points when said weights have been updated.

24. The apparatus of claim 19 wherein said means for selecting comprises:

means for successively applying a dynamic programming algorithm to select sets of operating points at successive power output values within a range of power output values the generator is capable of supplying; and

means for selecting a set of operating points corresponding to a last power output value in said range as said set of operating points for said genset.

25. The apparatus of claim 24 wherein said means for applying said dynamic programming algorithm comprises:

means for producing a first plurality of sums of cost values at a first power output value;

means for memoizing a result of at least one of said first plurality of said sums; and

means for using at least some of said memoized results for producing a further sum of cost values at a subsequent power output value.

26. The apparatus of claim 25 wherein said means for selecting comprises means for locating a minimum cost value at each power output value and wherein said means for successively applying said dynamic programming algorithm comprises means for first producing said sums of cost values corresponding to said minimum cost value at each successive power output value.

27. The apparatus of claim 26 wherein said means for locating said minimum cost value comprises means for implementing a golden section search technique.

28. The apparatus of claim 19 further comprising means for receiving a demand to supply power at a demanded power output value and means for operating the genset at an operating point in said set of operating points corresponding to said demanded power output value.

29. The apparatus of claim 28 wherein the genset is used to generate electrical energy for use in a hybrid vehicle and wherein said means for receiving said demand comprises means for receiving a demand to supply power to at least one of a drive motor, a charger operable to charge a storage element, and an accessory associated with the hybrid vehicle.

30. The apparatus of claim 29 wherein said means for receiving said demand to supply power to said charger comprises means for receiving a demand to supply power to said charger while said hybrid electric vehicle remains stationary.

31. The apparatus of claim 29 wherein said storage element comprises at least one of a storage battery, a capacitor, and an electrically coupled flywheel.

32. The apparatus of claim 29 wherein said means for receiving said demand to supply power to said drive motor comprises means for receiving a drive signal from an operator foot pedal representing a desired drive power to be supplied by said drive motor to wheels of said hybrid vehicle.

33. The apparatus of claim 32 wherein said storage element is operable to supply at least a first portion of said desired drive power, and wherein said demand comprises a demand for a second portion of said desired drive power.

34. The apparatus of claim 32 wherein said means for receiving said demand to supply power to said charger comprises means for receiving a charge signal from a storage element controller, said charge signal being produced in response to a state of charge associated with said storage element.

35. The apparatus of claim 19 further comprising means for receiving a plurality of cost values.

36. The apparatus of claim 35 further comprising means for selecting a new set of operating points in response to receiving said plurality of cost values.

37. The apparatus of claim 19 wherein said means for selecting comprises means for selecting said set of genset operating points prior to operating said genset.

38. An apparatus for selecting operating conditions of a genset, the genset comprising an engine coupled to an electrical power generator, the genset having a plurality of operating points each comprising an engine speed value and a generator electrical power output value, and having a plurality of cost values associated with operating the genset at respective operating points, the apparatus comprising:

a processor circuit operable to select a set of operating points from the plurality of operating points such that a sum of cost values associated with operating points in said set is minimized and such that the engine speed values of the operating points in said set increase or decrease monotonically as a function of the generator electrical power output values of the operating points in said set.

39. The apparatus of claim 38 wherein said processor circuit is operably configured to assign a weight to each of the power output values such that cost values corresponding to more frequently demanded power outputs are assigned a greater weight in said sum of cost values than cost values corresponding to less frequently demanded electrical power output values.

40. The apparatus of claim 39 wherein said processor circuit is operably configured to assign greater weight to electrical power output values proximate a midpoint of a range of power outputs that the generator is capable of supplying.

41. The apparatus of claim 39 wherein said processor circuit is operably configured to generate a record of received demands for power outputs during operation of the genset over a period of time and to assign greater weight to more frequently used power output values.

42. The apparatus of claim 41 wherein said processor circuit is operably configured to update said weights while operating the genset and to select a new set of operating points when said weights have been updated.

43. The apparatus of claim 38 wherein said processor circuit is operably configured to:

successively apply a dynamic programming algorithm to select sets of operating points at successive power output values within a range of power outputs the generator is capable of supplying; and

select a set of operating points corresponding to a last power output value in said range as said set of operating points for said genset.

44. The apparatus of claim 43 wherein said processor circuit is operably configured to:

produce a first plurality of sums of cost values at a first power output value;

memoize a result of at least one of said first plurality of said sums; and

use at least some of said memoized results for producing a further sum of cost values at a subsequent power output value.

45. The apparatus of claim 44 wherein said processor circuit is operably configured to locate a minimum cost value at each power output value and to apply said dynamic programming algorithm to first produce said sums of cost values corresponding to said minimum cost value at each successive power output value.

46. The apparatus of claim 45 wherein said processor circuit is operably configured to locate said minimum cost value using a golden section search technique.

47. The apparatus of claim 38 wherein said processor circuit is operably configured to receive a demand to supply power at a demanded power output value and to operate the genset at an operating point in said set of operating points corresponding to said demanded power output value.

48. The apparatus of claim 47 wherein the genset is used to generate electrical energy for use in a hybrid vehicle and wherein said processor circuit is operably configured to receive a demand to supply power to at least one of a drive motor, a charger operable to charge a storage element, and an accessory associated with the hybrid vehicle.

49. The apparatus of claim 48 wherein said processor circuit is operably configured to receive said demand to supply power to said charger while said hybrid electric vehicle remains stationary.

50. The apparatus of claim 48 wherein said storage element comprises at least one of a storage battery, a capacitor, and an electrically coupled flywheel.

51. The apparatus of claim 48 wherein said processor circuit is operably configured to receive a drive signal from an operator foot pedal representing a desired drive power to be supplied by said drive motor to wheels of said hybrid vehicle.

52. The apparatus of claim 51 wherein said storage element is operable to supply at least a first portion of said desired drive power, and wherein said demand comprises a demand for a second portion of said desired drive power.

53. The apparatus of claim 51 wherein said processor circuit is operably configured to receive a charge signal from a storage element controller, said charge signal being produced in response to a state of charge associated with said storage element.

54. The apparatus of claim 38 wherein said processor circuit is operably configured to receive a plurality of cost values.

55. The apparatus of claim 54 wherein said processor circuit is operably configured to select a new set of operating points in response to receiving said plurality of cost values.

56. The apparatus of claim 38 wherein said processor circuit is operably configured to select said set of genset operating points prior to operating the genset.

57. A computer readable medium encoded with codes for directing a processor circuit to perform a method for selecting optimal operating conditions of a genset, the genset comprising an engine coupled to an electrical power generator, the genset having a plurality of operating points each comprising an engine speed value and a generator electrical power output value, and having a plurality of cost values associated with operating the genset at respective operating points, the method comprising:

selecting a set of operating points from the plurality of operating points such that a sum of cost values associated with operating points in said set is minimized and such that the engine speed values of the operating points in said set increase or decrease monotonically as a function of the generator electrical power output values of the operating points in said set.

58. A data structure encoded on a computer readable medium for facilitating transfer of a set of operating points used in operating a genset, the genset comprising an engine coupled to an electrical power generator, the genset having a plurality of operating points each comprising an engine speed value and a generator electrical power output value, and having a plurality of cost values associated with operating the genset at respective operating points, the data structure comprising:

a set of operating points, each operating point comprising an engine speed data element and a linked power output data element, said engine speed data elements having monotonically increasing or decreasing values as a function of power output data elements in said set, said data elements in said set having values that minimize a sum of the cost values associated with operating the genset at respective operating points, said data structure being operable to provide an engine speed for operation of the genset at a selected power output.