Apparatus and method for identifying informative data in a process control environment

• US 7,257,501 B2
• Filed: 11/17/2005
• Issued: 08/14/2007
• Est. Priority Date: 11/17/2005
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Lu, Joseph Z., Zhan, Charles Q.
• Primary Examiner(s): Ramos-Feliciano; Eliseo
• Assistant Examiner(s): Huynh; Phuong
• Application Number:
  US11/281,849
• Publication Number:
  US 20070112531A1
• Time in Patent Office: 635 Days
• Field of Search: 702/69, 702/47, 702/109, 702/182, 702/185, 702/188, 702/189, 700/9, 73/10.1
• US Class Current: 702/69
• CPC Class Codes: G05B 13/042 in which a parameter or coefficient is automatically adjusted to optimise the performance

Abstract

A method includes identifying a signal and a disturbance using historical data associated with one or more process variables. The method also includes decomposing the signal and the disturbance at a plurality of resolution levels. The method further includes identifying a plurality of points associated with the decomposed signal using the decomposed signal and the decomposed disturbance. In addition, the method includes selecting at least some of the points and extracting a plurality of data segments from the signal, where the data segments are associated with the selected points.

Claims

1. A method, comprising:

identifying a signal and a disturbance using historical data associated with one or more process variables;

decomposing the signal and the disturbance at a plurality of resolution levels;

identifying a plurality of points associated with the decomposed signal using the decomposed signal and the decomposed disturbance;

selecting at least some of the points; and

extracting a plurality of data segments from the signal and storing the data segments, the data segments associated with the selected points.

2. The method of claim 1, wherein the plurality of points comprises local maximum and local minimum values in the decomposed signal at one or more of the resolution levels.

3. The method of claim 1, wherein selecting at least some of the points comprises:

determining at least one of a signal-to-noise ratio and a noise-to-signal ratio for each point using the decomposed signal and the decomposed disturbance.

4. The method of claim 3, wherein selecting at least some of the points further comprises:

selecting each point where at least one of the signal-to-noise ratio is above a first threshold and the noise-to-signal ratio is below a second threshold.

5. The method of claim 1, wherein extracting the plurality of data segments comprises:

extracting each data segment between a starting location and an ending location, the starting and ending locations determined using at least one of the decomposed signal and the decomposed disturbance.

6. The method of claim 5, further comprising determining the starting and ending locations based on where the decomposed signal crosses a threshold value.

7. The method of claim 5, further comprising determining the starting and ending locations based on where the decomposed disturbance crosses one or more threshold values.

8. The method of claim 1, wherein decomposing the signal and the disturbance comprises decomposing the signal and the disturbance using wavelet decomposition.

9. The method of claim 1, wherein the historical data associated with the one or more process variables comprises at least one of:

one or more measurements associated with one or more controlled variables; and

one or more measurements associated with one or more manipulated variables, the one or more manipulated variables used to control the one or more controlled variables via a model.

10. The method of claim 1, wherein decomposing the signal and the disturbance comprises decomposing the signal at the plurality of resolution levels and separately decomposing the disturbance at the plurality of resolution levels.

11. An apparatus, comprising:

at least one memory storing historical data associated with one or more process variables; and

at least one processor;

identifying a signal and a disturbance using the historical data;

decomposing the signal and the disturbance at a plurality of resolution levels;

identifying a plurality of points associated with the decomposed signal using the decomposed signal and the decomposed disturbance;

selecting at least some of the points; and

extracting a plurality of data segments from the signal and storing the data segments, the data segments associated with the selected points.

12. The apparatus of claim 11, wherein the plurality of points comprises local maximum and local minimum values in the decomposed signal at one or more of the resolution levels.

13. The apparatus of claim 11, wherein the at least one processor is capable of selecting at least some of the points by:

determining at least one of a signal-to-noise ratio and a noise-to-signal ratio for each point using the decomposed signal and the decomposed disturbance; and

selecting each point where at least one of;

the signal-to-noise ratio is above a first threshold and the noise-to-signal ratio is below a second threshold.

14. The apparatus of claim 11, wherein the at least one processor is capable of extracting the plurality of data segments by:

extracting each data segment between a starting location and an ending location, the starting and ending locations determined using at least one of the decomposed signal and the decomposed disturbance.

15. The apparatus of claim 14, wherein the at least one processor is capable of determining the starting and ending locations based on at least one of:

where the decomposed signal crosses a threshold value; and

where the decomposed disturbance crosses one or more threshold values.

16. The apparatus of claim 11, wherein the historical data associated with the one or more process variables comprises at least one of:

one or more measurements associated with one or more controlled variables; and

one or more measurements associated with one or more manipulated variables, the one or more manipulated variables used to control the one or more controlled variables via a model.

17. The apparatus of claim 16, wherein the at least one processor is further capable of processing the extracted data segments to validate the model.

18. A computer program embodied on a computer readable medium and operable to be executed by a processor, the computer program comprising computer readable program code for:

identifying a signal and a disturbance using historical data associated with one or more process variables;

decomposing the signal and the disturbance at a plurality of resolution levels;

identifying a plurality of points associated with the decomposed signal using the decomposed signal and the decomposed disturbance;

selecting at least some of the points; and

extracting a plurality of data segments from the signal and storing the data segments, the data segments associated with the selected points.

19. The computer program of claim 18, wherein the computer readable program code for selecting at least some of the points comprises computer readable program code for:

determining at least one of a signal-to-noise ratio and a noise-to-signal ratio for each point using the decomposed signal and the decomposed disturbance; and

selecting each point where at least one of;

the signal-to-noise ratio is above a first threshold and the noise-to-signal ratio is below a second threshold.

20. The computer program of claim 18, wherein the computer readable program code for extracting the plurality of data segments comprises computer readable program code for:

extracting each data segment between a starting location and an ending location, the starting and ending locations determined using at least one of the decomposed signal and the decomposed disturbance.

21. The computer program of claim 20, further comprising computer readable program code for determining the starting and ending locations based on at least one of:

where the decomposed signal crosses a threshold value; and

where the decomposed disturbance crosses one or more threshold values.