Method and apparatus for verifying the operation of an accelerometer

• US 8,099,993 B2
• Filed: 12/20/2007
• Issued: 01/24/2012
• Est. Priority Date: 12/20/2007
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: van der Merwe, Gert J., Bradford, David Allen
• Primary Examiner(s): Williams, Hezron E
• Assistant Examiner(s): Shah, Samir M
• Application Number:
  US11/961,466
• Publication Number:
  US 20090158845A1
• Time in Patent Office: 1,496 Days
• Field of Search: 73/13.7, 734/62, 73/13.8, 73/66
• US Class Current: 73/1.37
• CPC Class Codes: G01M 1/22 and converting vibrations due to imbalance into electric variables
• CPC Class Codes: G01M 15/14 Testing gas-turbine engines or jet-propulsion engines
• CPC Class Codes: G01P 21/00 Testing or calibrating of apparatus or devices covered by the preceding groups

Abstract

A method of verifying the operation of an accelerometer is provided. The method includes channeling a high frequency signal through a positive lead of the accelerometer, and detecting a signal at a negative lead of the accelerometer. If the detected signal is substantially similar to the high frequency signal channeled through the positive lead, the integrity of the accelerometer is verified.

Claims

1. A method of verifying the operation of an accelerometer that includes a piezo element, said method comprising:

channeling a high frequency signal from an output of a signal source to the piezo element through a positive lead that is electrically coupled to the piezo element; and

at an input of a monitoring device, detecting a signal from a negative lead that is electrically coupled to the piezo element, wherein, if the detected signal from the negative lead is substantially similar to the high frequency signal channeled through the positive lead, the integrity of the accelerometer is verified.

2. A method in accordance with claim 1, further comprising channeling the high frequency signal through the piezo element.

3. A method in accordance with claim 1, further comprising distinguishing intermittent faults in the accelerometer from continuous faults in the accelerometer.

4. A method in accordance with claim 1, wherein channeling a high frequency signal through a positive lead further comprises continuously channeling a high frequency signal through the positive lead.

5. A method in accordance with claim 1, wherein channeling a high frequency signal through a positive lead further comprises channeling a signal having a frequency that is different from an operating frequency of a machine that the accelerometer monitors.

6. A method in accordance with claim 1, further comprising channeling the high frequency signal through the accelerometer prior to operating a machine monitored by the accelerometer.

7. A method in accordance with claim 1, further comprising verifying the operation of an accelerometer used to detect rotor imbalances in a turbine engine.

8. A charger converter for use in verifying the operation of an accelerometer that includes a piezo element, said converter comprising:

a signal source for generating a high frequency signal;

an output for channeling the high frequency signal from the signal source to the piezo element through a positive lead that is electrically coupled to the piezo element; and

an input for detecting a signal at a negative lead that is electrically coupled to the piezo element, wherein, if the detected signal is substantially similar to the high frequency signal channeled through the positive lead, the integrity of the accelerometer is verified.

9. A converter in accordance with claim 8, wherein said output channels the high frequency signal through the piezo element.

10. A converter in accordance with claim 8, wherein said input distinguishes intermittent faults in the accelerometer from continuous faults in the accelerometer.

11. A converter in accordance with claim 8, wherein said output continuously channels the high frequency signal through the positive lead.

12. A converter in accordance with claim 8, wherein said output channels a signal having a frequency that is different from an operating frequency of a machine that the accelerometer monitors.

13. A converter in accordance with claim 8, wherein said output channels the high frequency signal through the accelerometer prior to operating a machine monitored by the accelerometer.

14. A converter in accordance with claim 8, wherein said converter verifies the operation of an accelerometer used to detect rotor imbalances in a turbine engine.

15. A turbine engine comprising:

a rotor;

an accelerometer that monitors an unbalance of said rotor, said accelerometer comprising a piezo element; and

a charge converter that verifies the operation of said accelerometer by;

channeling a high frequency signal to the piezo element through a positive lead that is electrically coupled to the piezo element; and

detecting a signal discharged from said accelerometer via a negative lead that is electrically coupled to the piezo element, wherein, if the detected signal is substantially similar to the high frequency signal channeled through the positive lead, the integrity of an accelerometer signal chain is verified.

16. A turbine engine in accordance with claim 15, wherein said charge converter further verifies the integrity of said accelerometer by channeling the high frequency signal through the piezo element.

17. A turbine engine in accordance with claim 15, wherein said charge converter further verifies the integrity of said accelerometer by distinguishing intermittent faults in said accelerometer from continuous faults in said accelerometer.

18. A turbine engine in accordance with claim 15, wherein said charge converter further verifies the integrity of said accelerometer by continuously channeling a high frequency signal through said accelerometer.

19. A turbine engine in accordance with claim 15, wherein said charge converter further verifies the integrity of said accelerometer by channeling a signal having a frequency that is different from an operating frequency of said rotor.

20. A turbine engine in accordance with claim 15, wherein said charge converter further verifies the integrity of said accelerometer by channeling the high frequency signal through said accelerometer prior to operating said rotor.