Health monitoring and diagnostic/prognostic system for an ORC plant

• US 20050171736A1
• Filed: 02/02/2004
• Published: 08/04/2005
• Est. Priority Date: 02/02/2004
• Status: Abandoned Application

• Current Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Kang, Pengju
• Application Number:
  US10/770,155
• Publication Number:
  US 20050171736A1
• Time in Patent Office: Days
• US Class Current: 702/185
• CPC Class Codes: G01H 1/006 of the rotor of turbo machines

Abstract

An organic rankine cycle turbine generator includes one or more embedded sensor devices that incorporate both a 3-axis accelerometer and a digital signal processing board. The device monitors, processes, analyses and stores vibrational data to determine whether and when the defect occurs in a turbine or generator component so that appropriate action may be taken. Prognostic analysis is also performed to determine the life of a faulty component.

Claims

1. A diagnostic system for on-line monitoring and analysis of vibrational performance of a turbine generator for the purpose of determining the operational condition of its components, comprising:

at least one sensor attached to said turbine generator for sensing vibrations thereof and for generating representative vibration signals;

a signal processor for receiving said vibration signals and for generating pdf signals that are representative of their probability density functions; and

comparing means for comparing said pdf signals with predetermined values for determining whether a fault exists in the components.

2. A diagnostic system as set forth in claim 1 wherein said at least one sensor is an accelerometer.

3. A diagnostic system as set forth in claim 2 wherein said accelerometer is of the 3-axis type wherein said accelerometer is capable of simultaneously sensing vibrations in three different axes.

4. A diagnostic system as set forth in claim 2 wherein said accelerometer is of the PCB type.

5. A diagnostic system as set forth in claim 1 wherein said at least one sensor includes two sensors, with one being attached to a turbine portion of the turbine generator and one being attached to a generator portion of the turbine generator.

6. A diagnostic system as set forth in claim 1 wherein said signal processor is embedded in said sensor.

7. A diagnostic system as set forth in claim 1 wherein said signal processor also includes a filter for filtering the vibration signals.

8. A diagnostic system as set forth in claim 7 wherein the component is a bearing and further wherein said filter is a low pass filter.

9. A diagnostic system as set forth in claim 7 wherein the component is a gear and further wherein said filter is a notch filter.

10. A diagnostic system as set forth in claim 7 wherein the component is an impeller and further wherein said filter is a band pass filter.

11. A diagnostic system as set forth in claim 1 wherein said signal processor also includes means for applying a wavelet transform to the vibration signal.

12. A diagnostic system as set forth in claim 11 wherein signal processor generates said pdf signals by orthogonal statistical said expansion.

13. A diagnostic system as set forth in claim 1 and further including means for shutting down the turbine generator when a fault exists.

14. A method of monitoring an on-line turbine generator for possible faults in its rotational components comprising the steps of:

sensing the vibration of the components and generating representative vibrational signals thereof;

applying a wavelet transform (wt) to the filtered signals to obtain representative wavelet coefficients;

calculating the probability density function (pdf) of the wavelet coefficients; and

comparing said pdf with stored data to determine whether a fault exists.

15. A method as set forth in claim 14 and including an additional step of filtering said vibrational signal to eliminate non-relevant portions thereof.

16. A method as set forth in claim 14 wherein the rotational component is a bearing and further wherein said filtering process uses a low pass filter.

17. A method as set forth in claim 14 wherein the rotational component is a gear and further wherein said filtering function uses a notch filter.

18. A method as set forth in claim 14 wherein the rotational component is an impeller and further wherein said filtering step is accomplished by using a band pass filter.

19. A method as set forth in claim 14 and including a further step of modifying the operation of the turbine generator when a fault has been determined to exist.

20. A method as set forth in claim 14 and including the further step of conducting spectral analysis of a vibration signals to determine expected life of the rotational component.