Traction motor speed sensor failure detection for an AC locomotive

• US 6,456,908 B1
• Filed: 10/26/2000
• Issued: 09/24/2002
• Est. Priority Date: 10/26/2000
• Status: Expired due to Term

• Current Assignee: GE Global Sourcing LLC (Westinghouse Air Brake Technologies Corporation)
• Original Assignee: General Electric Company
• Inventors: Kumar, Ajith Kuttannair
• Primary Examiner(s): LOUIS JACQUES, JACQUES H
• Application Number:
  US09/704,213
• Time in Patent Office: 698 Days
• Field of Search: 701/19, 701/20, 701/29, 318/490, 318/459, 318/52, 318/807, 318/565, 318/68, 104/307, 105/26.05, 105/49, 105/61, 700/45, 700/79, 290/3, 290/9, 290/45, 290/40.B, 290/40.C, 322/14, 322/16, 246/122.R
• US Class Current: 701/19
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 3/0023 Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train

Abstract

A system for detecting a failure of a speed sensor on a locomotive propelled by an AC traction motor is disclosed. The system includes a locomotive including a processor for executing a detection method. The method comprises conducting an evaluation of symptoms exhibited by a speed sensor. A health value representative of health of the speed sensor is generated and modified as a function of an evaluation, and as a result from the modification of the health value, a modified health value is generated. A motor control methodology responsive to the modified health value is selected.

Claims

1. A method for detecting a failure of a speed sensor on a locomotive propelled by an AC traction motor, the method comprising:

conducting at least one evaluation of symptoms exhibited by a speed sensor;

modifying at least one health value representative of health of said speed sensor as a function of said at least one evaluation;

generating at least one modified health value as resultant from said modifying; and

selecting a motor control methodology responsive to said at least one modified health value.

2. The method of claim 1 wherein said modifying comprises a duration based reduction in said at least one health value.

3. The method of claim 1 wherein said modifying is characterized by a reduction of said at least one health value via a predetermined process for each at least one evaluation.

4. The method of claim 1 wherein said selecting is characterized by transitioning motor control to speed sensor-less control when said at least one modified health value decreases below a threshold of about 95 percent.

5. The method of claim 1 wherein said selecting is characterized by transitioning motor control to speed sensor-less control with priority when said at least one modified health value decreases below a threshold of about 76 percent.

6. The method of claim 1 wherein said selecting is characterized by transitioning motor control to speed sensor-less control and informing that maintenance is required when said at least one modified health value decreases below a threshold of about 5 percent.

7. The method of claim 1 wherein said at least one evaluation is characterized by an indirect evaluation.

8. The method of claim 7 wherein said indirect evaluation is characterized by an over-current evaluation.

9. The method of claim 7 wherein said indirect evaluation is characterized by an over-voltage evaluation.

10. The method of claim 7 wherein said indirect evaluation is characterized by a motor torque sign and magnitude evaluation.

11. The method of claim 1 wherein said at least one evaluation is characterized by a direct evaluation.

12. The method of claim 11 wherein said direct evaluation is characterized by a rate and magnitude reasonableness evaluation.

13. The method of claim 11 wherein said direct evaluation is characterized by an intermittent output evaluation.

14. The method of claim 1 wherein said at least one evaluation is characterized by a comparative evaluation.

15. The method of claim 14 wherein said comparative evaluation is characterized by an individual signal quality evaluation.

16. The method of claim 14 wherein said comparative evaluation is characterized by a secondary sensor reasonableness evaluation.

17. The method of claim 14 wherein said comparative evaluation is characterized by a locked axle evaluation.

18. The method of claim 14 wherein said comparative evaluation is characterized by a distance evaluation.

19. The method of claim 1 further comprising a recovery process of said at least one health value if said at least one evaluation indicates absence of said failure of said speed sensor.

20. The method of claim 1 further including combining said at least one health value with at least one other health value.

21. The method of claim 20 wherein said combining is characterized by a weighted sum of said at least one health value and said at least one other health value.

22. The method claim 20 wherein said combining is characterized by individual consideration of a threshold for at least one of each said at least one health value and each said at least one other health value.

23. The method claim 20 wherein said combining is characterized by a composite health value subject to modification by each of said at least one evaluation.

24. The method of claim 20 wherein said modifying comprises a duration based reduction of at least one of said at least one health value and said at least one other health value.

25. The method of claim 20 wherein said modifying is characterized by a reduction of at least one of said at least one health value said at least one other health value.

26. The method of claim 20 wherein said selecting is characterized by transitioning motor control to speed sensor-less control when said at least one modified health value decreases below a threshold of about 95 percent.

27. The method of claim 20 wherein said selecting is characterized by transitioning motor control to speed sensor-less control with priority when said at least one modified health value decreases below a threshold of about 76 percent.

28. The method of claim 20 wherein said selecting is characterized by transitioning motor control to speed sensor-less control and informing an operator that maintenance is required when said at least one modified health value decreases below a threshold of about 5 percent.

29. The method of claim 20 wherein said at least one evaluation is characterized by an indirect evaluation.

30. The method of claim 29 wherein said indirect evaluation is characterized by an over-current evaluation.

31. The method of claim 30 wherein said indirect evaluation is characterized by a motor torque sign and magnitude evaluation.

32. The method of claim 29 wherein said indirect evaluation is characterized by an over-voltage evaluation.

33. The method of claim 20 wherein said at least one evaluation is characterized by a direct evaluation.

34. The method of claim 33 wherein said direct evaluation is characterized by a rate and magnitude reasonableness evaluation.

35. The method of claim 33 wherein said direct evaluation is characterized by an intermittent output evaluation.

36. The method of claim 20 wherein said at least one evaluation is characterized by a comparative evaluation.

37. The method of claim 36 wherein said comparative evaluation is characterized by an individual signal quality evaluation.

38. The method of claim 36 wherein said comparative evaluation is characterized by a secondary sensor reasonableness evaluation.

39. The method of claim 36 wherein said comparative evaluation is characterized by a locked axle evaluation.

40. The method of claim 36 wherein said comparative evaluation is characterized by a distance evaluation.

41. The method of claim 20 wherein said selecting is characterized by transitioning motor control to speed sensor-less control when said at least one modified health value decreases below a selected threshold.

42. The method of claim 1 wherein said selecting is characterized by transitioning motor control to speed sensor-less control when said at least one modified health value decreases below a selected threshold.

43. A system for detecting a failure of a speed sensor on a locomotive propelled by an AC traction motor, the system comprising:

a locomotive propulsion system including a traction motor connected to an axle in a driving relationship;

a speed sensor configured to detect a rotational speed of said traction motor;

a controller coupled to said speed sensor and said motor;

wherein said controller performs processing to carry out a method of;

conducting at least one evaluation of symptoms exhibited by a speed sensor;

modifying at least one health value representative of health of said speed sensor as a function of said at least one evaluation;

generating at least one modified health value as resultant from said modifying; and

selecting a motor control methodology responsive to said at least one modified health value.

44. The system of claim 43 wherein said modifying comprises a duration based reduction in said at least one health value.

45. The system of claim 43 wherein said modifying is characterized by a reduction of said at least one health value via a predetermined process for each at least one evaluation.

46. The system of claim 43 wherein said selecting is characterized by transitioning motor control to speed sensorless control when said at least one modified health value decreases below a threshold of about 95 percent.

47. The system of claim 43 wherein said selecting is characterized by transitioning motor control to speed sensor-less control with priority when said at least one modified health value decreases below a threshold of about 76 percent.

48. The system of claim 43 wherein said selecting is characterized by transitioning motor control to speed sensor-less control and informing an operator that maintenance is required when said at least one modified health value decreases below a threshold of about 5 percent.

49. The system of claim 43 wherein said at least one evaluation is characterized by an indirect evaluation.

50. The system of claim 49 wherein said indirect evaluation is characterized by an over-current evaluation.

51. The system of claim 49 wherein said indirect evaluation is characterized by an over-voltage evaluation.

52. The system of claim 49 wherein said indirect evaluation is characterized by a motor torque sign and magnitude evaluation.

53. The system of claim 43 wherein said at least one evaluation is characterized by a direct evaluation.

54. The system of claim 53 wherein said direct evaluation is characterized by a rate and magnitude reasonableness evaluation.

55. The system of claim 53 wherein said direct evaluation is characterized by an intermittent output evaluation.

56. The system of claim 43 wherein said at least one evaluation is characterized by a comparative evaluation.

57. The system of claim 56 wherein said comparative evaluation is characterized by an individual signal quality evaluation.

58. The system of claim 56 wherein said comparative evaluation is characterized by a secondary sensor reasonableness evaluation.

59. The system of claim 56 wherein said comparative evaluation is characterized by a locked axle evaluation.

60. The system of claim 56 wherein said comparative evaluation is characterized by a distance evaluation.

61. The system of claim 43 further comprising a recovery process of said at least one health value if said at least one evaluation indicates absence of said failure of said speed sensor.

62. The system of claim 43 further including combining said at least one health value with at least one other health value.

63. The system of claim 62 wherein said combining is characterized by a weighted sum of said at least one health value and said at least one other health value.

64. The system claim 62 wherein said combining is characterized by individual consideration of a threshold for at least one of each said at least one health value and each said at least one other health value.

65. The system claim 62 wherein said combining is characterized by a composite health value subject to modification by each of said at least one evaluation.

66. The system of claim 62 wherein said modifying comprises a duration based reduction of at least one of said at least one health value and said at least one other health value.

67. The system of claim 62 wherein said modifying is characterized by a reduction of at least one of said at least one health value said at least one other health value.

68. The system of claim 62 wherein said selecting is characterized by transitioning motor control to speed sensor-less control when said at least one modified health value decreases below a threshold of about 95 percent.

69. The system of claim 62 wherein said selecting is characterized by transitioning motor control to speed sensor-less control with priority when said at least one modified health value decreases below a threshold of about 76 percent.

70. The system of claim 62 wherein said selecting is characterized by transitioning motor control to speed sensor-less control and informing an operator that maintenance is required when said at least one modified health value decreases below a threshold of about 5 percent.

71. The system of claim 62 wherein said at least one evaluation is characterized by an indirect evaluation.

72. The system of claim 71 wherein said indirect evaluation is characterized by an over-current evaluation.

73. The system of claim 71 wherein said indirect evaluation is characterized by an over-voltage evaluation.

74. The system of claim 71 wherein said indirect evaluations is characterized by a motor torque sign and magnitude evaluation.

75. The system of claim 62 wherein said at least one evaluation is characterized by a direct evaluation.

76. The system of claim 75 wherein said direct evaluation is characterized by a rate and magnitude reasonableness evaluation.

77. The system of claim 75 wherein said direct evaluation is characterized by an intermittent output evaluation.

78. The system of claim 62 wherein said at least one evaluation is characterized by a comparative evaluation.

79. The system of claim 78 wherein said comparative evaluation is characterized by an individual signal quality evaluation.

80. The system of claim 78 wherein said comparative evaluation is characterized by a secondary sensor reasonableness evaluation.

81. The system of claim 78 wherein said comparative evaluation is characterized by a locked axle evaluation.

82. The system of claim 78 wherein said comparative evaluation is characterized by a distance evaluation.

83. The system of claim 62 wherein said selecting is characterized by transitioning motor control to speed sensor-less control when said at least one modified health value decreases below a selected threshold.

84. The system of claim 43 wherein said selecting is characterized by transitioning motor control to speed sensor-less control when said at least one modified health value decreases below a selected threshold.