Sensor assembly and method of measuring the proximity of a machine component to a sensor

• US 8,854,052 B2
• Filed: 11/22/2010
• Issued: 10/07/2014
• Est. Priority Date: 11/22/2010
• Status: Active Grant

• Current Assignee: Baker Hughes, a GE Company, LLC (Baker Hughes Company)
• Original Assignee: General Electric Company
• Inventors: Sheikman, Boris Leonid, Go, Steven
• Primary Examiner(s): Nguyen, Tung X
• Application Number:
  US12/951,447
• Publication Number:
  US 20120126826A1
• Time in Patent Office: 1,415 Days
• US Class Current: 324/629
• CPC Class Codes: G01B 15/00 Measuring arrangements characterised by the use of electromagnetic waves or particle radiation, e.g. by the use of microwaves, X-rays, gamma rays or electrons characterised by the use of optical techniques G01B9/00, G01B11/00
• CPC Class Codes: G01B 7/023 for measuring distance between sensor and object G01B7/082 and G01B7/102 take precedence

Abstract

A microwave sensor assembly includes a signal processing device for generating at least one microwave signal that includes a pattern of frequencies and at least one probe coupled to the signal processing device. The probe includes an emitter configured to generate an electromagnetic field from the at least one microwave signal, wherein the emitter is detuned when an object is positioned within the electromagnetic field such that a loading signal is reflected from the emitter to the signal processing device.

Claims

1. A microwave sensor assembly comprising:

a signal processing device for generating at least one microwave signal that includes a pattern of frequencies, wherein the signal processing device is configured to;

calculate a first amount of a microwave signal power contained in the at least one microwave signal;

calculate a second amount of a loading signal power contained in the loading signal; and

calculate a proximity of an object to the emitter based on a difference between the first amount of the microwave signal power and the second amount of the loading signal power; and

at least one probe coupled to the signal processing device, the at least one probe comprising an emitter configured to generate an electromagnetic field from the at least one microwave signal, wherein the emitter is detuned when an object is positioned within the electromagnetic field such that a loading signal is reflected from the emitter to the signal processing device.

2. The microwave sensor assembly in accordance with claim 1, wherein the pattern of frequencies of the at least one microwave signal is proportional to a power distribution of the pattern of frequencies.

3. The microwave sensor assembly in accordance with claim 1, wherein the pattern of frequencies of the at least one microwave signal is inversely proportional to a power distribution of the pattern of frequencies.

4. The microwave sensor assembly in accordance with claim 1, wherein the pattern of frequencies of the at least one microwave signal is within a plurality of frequency bands, wherein a power distribution of a first frequency band of the plurality of frequency bands is substantially equal to a power distribution of a second frequency band of the plurality of frequency bands.

5. The microwave sensor assembly in accordance with claim 4, wherein the frequency range of the first frequency band is proportional to the frequency range of the second frequency band.

6. The microwave sensor assembly in accordance with claim 1, wherein the emitter is configured to generate a substantially linear output in relation to a distance of an object to the emitter when the emitter is driven by the at least one microwave signal.

7. The microwave sensor assembly in accordance with claim 6, wherein the emitter is further configured to generate a substantially linear output in relation to the distance of the object to the emitter when the emitter is driven by the at least one microwave signal, the at least one microwave signal including a pattern of frequencies that is inversely proportional to a power spectral density of the frequencies.

18. The microwave sensor assembly in accordance with claim 1, wherein the loading signal is representative of a disruption of the electromagnetic field, and the signal processing device is configured to calculate the proximity of the object to the emitter based on the loading signal.

20. The microwave sensor assembly in accordance with claim 1, wherein the at least one microwave signal comprises a pink noise signal.

8. A power system comprising:

a machine comprising at least one component; and

a microwave sensor assembly positioned proximate to the at least one component, the microwave sensor assembly comprising;

a signal processing device for generating at least one microwave signal that includes a pattern of frequencies, wherein the signal processing device is configured to;

calculate a first amount of a microwave signal power contained in the at least one microwave signal;

calculate a second amount of a loading signal power contained in the loading signal; and

calculate a proximity of the at least one component to the emitter based on a difference between the first amount of the microwave signal power and the second amount of the loading signal power; and

at least one probe coupled to the signal processing device, the at least one probe comprising an emitter configured to generate an electromagnetic field from the at least one microwave signal, wherein the emitter is detuned when an object is positioned within the electromagnetic field such that a loading signal is reflected from the emitter to the signal processing device.

9. The power system in accordance with claim 8, wherein the pattern of frequencies of the at least one microwave signal is proportional to a power distribution of the pattern of frequencies.

10. The power system in accordance with claim 8, wherein the pattern of frequencies of the at least one microwave signal is inversely proportional to a power distribution of the pattern of frequencies.

11. The power system in accordance with claim 8, wherein the pattern of frequencies of the at least one microwave signal is within a plurality of frequency bands, wherein a power distribution of a first frequency band of the plurality of frequency bands is substantially equal to a power distribution of a second frequency band of the plurality of frequency bands.

12. The power system in accordance with claim 11, wherein the frequency range of the first frequency band is proportional to the frequency range of the second frequency band.

13. The power system in accordance with claim 8, wherein the emitter is configured to generate a substantially linear output in relation to a distance from the at least one component to the emitter when the emitter is driven by the at least one microwave signal.

14. The power system in accordance with claim 13, wherein the emitter is further configured to generate a substantially linear output in relation to the distance from the at least one component to the emitter when the emitter is driven by the at least one microwave signal, the at least one microwave signal including a pattern of frequencies that is inversely proportional to a power spectral density of the frequencies.

19. The power system in accordance with claim 8, wherein the loading signal is representative of a disruption of the electromagnetic field, and the signal processing device is configured to calculate the proximity of the at least one component to the emitter based on the loading signal.

21. The power system in accordance with claim 8, wherein the at least one microwave signal comprises a pink noise signal.

15. A method for measuring a proximity of a machine component relative to an emitter, the method comprising:

transmitting at least one microwave signal that includes a pattern of frequencies to the emitter;

generating an electromagnetic field from the at least one microwave signal;

generating a loading signal representative of a disruption of the electromagnetic field when the machine component is positioned within the electromagnetic field;

calculating a first amount of a microwave signal power contained in the at least one microwave signal;

calculating a second amount of a loading signal power contained in the loading signal; and

calculating the proximity of the machine component to the emitter based on a difference between the first amount of the microwave signal power and the second amount of the loading signal power; and

calculating the proximity of the machine component to the emitter based on the loading signal.

16. The method in accordance with claim 15, wherein the pattern of frequencies of the at least one microwave signal is inversely proportional to a power distribution of the pattern of frequencies.

17. The method in accordance with claim 15, wherein the pattern of frequencies of the at least one microwave signal is within a plurality of frequency bands, wherein a power distribution of a first frequency band of the plurality of frequency bands is substantially equal to a power distribution of a second frequency band of the plurality of frequency bands.

22. The method in accordance with claim 15, wherein the at least one microwave signal comprises a pink noise signal.