Off-line diagnosis system

• US 20050216232A1
• Filed: 05/26/2005
• Published: 09/29/2005
• Est. Priority Date: 09/30/2002
• Status: Active Grant

• Current Assignee: Dresser, LLC (GE Aerospace)
• Original Assignee: Dresser Incorporated (Nagano Keiki Company Limited)
• Inventors: Hashizumi, Kazuhiro, Saito, Yoji, Du, Hongli, Legere, Alex
• Granted Patent: US 7,181,367 B2
• Time in Patent Office: Days
• US Class Current: 702/183
• CPC Class Codes: G05B 19/4185 characterised by the network communication
• CPC Class Codes: G05B 2219/31211 Communicate diagnostic data from intelligent field device controller to central
• CPC Class Codes: G05B 2219/33326 Analyzer, diagnostic for servovalve
• CPC Class Codes: G05B 2219/33331 Test, diagnostic of field device for correct device, correct parameters
• CPC Class Codes: G05B 23/021 adopting a different treatment of each operating region or a different mode of the monitored system, e.g. transient modes; different operating configurations of monitored system
• CPC Class Codes: G05B 23/0221 Preprocessing measurements, e.g. data collection rate adjustment; Standardization of measurements; Time series or signal analysis, e.g. frequency analysis or wavelets; Trustworthiness of measurements; Indexes therefor; Measurements using easily measured parameters to estimate parameters difficult to measure; Virtual sensor creation; De-noising; Sensor fusion; Unconventional preprocessing inherently present in specific fault detection methods like PCA-based methods
• CPC Class Codes: G05B 23/0256 injecting test signals and analyzing monitored process response, e.g. injecting the test signal while interrupting the normal operation of the monitored system; superimposing the test signal onto a control signal during normal operation of the monitored system
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

The present invention provides an off-line diagnosis system whereby the measurement resolution (number of measurement points) can be increased in order to obtain detailed input-output characteristics, and step response characteristics can be obtained at a sufficient frequency and more efficiently, without expanding the physically limited memory capacity of a field instrument or host application. The off-line diagnosis system comprises a field instrument that performs process control and has a self-diagnosis function or a valve diagnosis function and a host application that performs digital communication with the field instrument, wherein the self-diagnosis of the field instrument is executed or the diagnosis of a valve is executed during an off-line interval and diagnosis results are transmitted to the host application, and wherein the signal input range of the field instrument or the valve is divided into a plurality of zones with respect to the time axis or input axis, and the diagnosis results of each zone are successively transmitted to the host application.

Claims

1-25. -25. (canceled)

26. A process-control diagnosis system, the system comprising:

a field instrument for use in a process-control system, the field instrument comprising memory of a predetermined capacity and a data transmitter, the field instrument operable to;

perform a diagnosis function for at least two zones of a signal input range that is divided into a plurality of zones,

store diagnosis results for a first zone in a memory location,

transmit the diagnosis results for the first zone, and

store diagnosis results for a second zone in the memory location, wherein the combined size of the diagnosis results for the first zone and of the diagnosis results for the second zone is larger than the diagnosis-results capacity of the memory location.

27. The system of claim 26, wherein the field instrument is operable to divide the signal input range into the zones.

28. The system of claim 27, wherein the signal input range is divided with respect to an input axis or a time axis.

29. The system of claim 26, wherein the diagnosis function comprises a self-diagnosis function for the field instrument.

30. The system of claim 26, wherein the diagnosis results for the first zone are transmitted while the diagnosis results for the second zone are stored in the memory location.

31. The system of claim 26, further comprising a host application in digital communication with the field instrument, wherein diagnosis results for the first zone and the second zone are successively received by the host application.

32. The system of claim 26, wherein the diagnosis function is based on input-output characteristics measurement, in which an input is given to a component being diagnosed and then an output value thereof is measured.

33. The system of claim 32, wherein the output characteristics are of a valve.

34. The system of claim 32, wherein the diagnosis results comprise measurement data points.

35. The system of claim 26, wherein the field instrument is a valve positioner.

36. The system of claim 26, further comprising:

successively obtaining diagnosis results for each zone; and

successively transmitting the measurement data points for each zone.

37. The system of claim 26, wherein the memory has a maximum capacity for a predetermined amount of diagnosis results, and the amount of diagnosis results for each zone is less than or equal to the predetermined amount.

38. A method for process-control diagnosis, the method comprising:

performing a diagnosis function for at least two zones of a signal input range that is divided into a plurality of zones with a field instrument;

storing diagnosis results for a first zone in a memory location of the field instrument;

transmitting the diagnosis results for the first zone from the field instrument;

storing diagnosis results for a second zone in the memory location, wherein the combined size of the diagnosis results for the first zone and of the diagnosis results for the second zone is larger than the diagnosis-results capacity of the memory location.

39. The method of claim 38, further comprising dividing the signal input range into the plurality of zones.

40. The method of claim 38, further comprising successively receiving the diagnosis results for the first zone and the second zone at a host application.

41. The method of claim 38, wherein the diagnosis results for the first zone are transmitted while the diagnosis results for the second zone are stored in the memory location.

42. A process-control diagnosis system, the system comprising:

a field instrument for use in a process-control system, the field instrument operable to;

perform a diagnosis function for at least two zones of a signal input range that is divided into a plurality of zones, and

successively transmit diagnosis results for the first zone and diagnosis results for the second zone.

43. The system of claim 42, wherein the field instrument is operable to:

store the diagnosis results for the first zone in a memory location,

transmit the diagnosis results for the first zone, and

store the diagnosis results for the second zone in the memory location, wherein the combined size of the diagnosis results for the first zone and of the diagnosis results for the second zone is larger than the diagnosis-results capacity of the memory location.

44. The system of claim 43, wherein the memory has a maximum capacity for a predetermined amount of diagnosis results, and the amount of diagnosis results for each zone is less than or equal to the predetermined amount.

45. The system of claim 42, further comprising:

successively obtaining diagnosis results for each zone; and

successively transmitting the diagnosis results for each zone.