Patent US6816810B2 successfully refreshed from Google Patents.
US6816810B2
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Process monitoring and control using self-validating sensors
Assignee: Schneider Electric Systems USA Inc
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Filing: 2001-03-23
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Granted: 2004-11-09
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Expires: 2021-03-23
Abstract
Abstract Self-validating (SEVA) sensors implemented in a control process provide various metrics regarding sensed variables to a central control unit. Specifically, SEVA sensors provide measurements of the variables and validity information about the measurements, which may include fault information about the sensors themselves. A control unit utilizes the various SEVA metrics even when large numbers of SEVA sensors are used, a situation that is otherwise problematic due to difficulties in assimilating data from multiple SEVA sensors. Accordingly, the control unit distinguishes sensor faults from actual process changes, and responds as needed, even when large numbers of SEVA sensors are implemented together. Specifically, the monitoring and control unit assimilates signals from multiple SEVA sensors using a multi-variate statistical analysis, and compares results of this analysis with a model characterizing behavior of the process (where the model may take into account actuator position information) and/or historical statistical data.
Inventors
- 👤 Manus P. Henry
- 👤 David J. Sandoz
- 👤 David W. Clarke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:08
CPC Classifications
G; G08; G08B; G08B31/00; G01; G01K; G01K15/00; G08B29/00; G08B29/18; G08B29/20
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
154 words
A multi-level process monitoring system comprising a process monitoring unit, at a higher level of the system, and a plurality of sensors at a lower level of the system, at least one of the sensors having self-validating capability the sensors being adapted to provide respective measurement values of respective process variables to said monitoring unit, said monitoring unit being so arranged as to monitor the outputs of the sensors and to identily any significant apparent change in the process conditions based on a comparison of apparent process status information, which is obtained by a combination of said sensor outputs, with reference information, and on detection of an apparent significant change, to request additional status information from at least one of the SEVA sensor/s to determine whether the apparent change is in reality due to a change in the characteristics of a particular SEVA sensor rather than an actual significant change in the process conditions.
Claim 2
Dependent Claim
154 words
A multi-level process monitoring system comprising a process monitoring unit, at a higher level of the system, and a plurality of sensors at a lower level of the system, at least one of the sensors having self-validating capability the sensors being adapted to provide respective measurement values of respective process variables to said monitoring unit, said monitoring unit being so arranged as to monitor the outputs of the sensors and to identily any significant apparent change in the process conditions based on a comparison of apparent process status information, which is obtained by a combination of said sensor outputs, with reference information, and on detection of an apparent significant change, to request additional status information from at least one of the SEVA sensor/s to determine whether the apparent change is in reality due to a change in the characteristics of a particular SEVA sensor rather than an actual significant change in the process conditions.
Claim 3
Dependent Claim
31 words
A process monitoring system as claimed in claim 1 comprising one or more actuators to effect process changes, the actuators being arranged to provide the monitoring unit with actuator position signals.
Claim 4
Dependent Claim
18 words
A process monitoring system as claimed in claim 1 in which most of the sensors are SEVA sensors.
Claim 5
Dependent Claim
58 words
A process monitoring system as claimed in claim 1 in which the monitoring unit obtains the overview using a multivariate statistical analysis of the measurement values of the sensors, and compares the results of that analysis with the reference information to identify any significant apparent change in process conditions, to determine to initiate interrogation of the SEVA sensor/s.
Claim 6
Dependent Claim
28 words
A process monitoring system as claimed in claim 4 in which the reference information is comprised of predictions of a model and historical data of stored statistical analyses.
Claim 7
Dependent Claim
17 words
A process monitoring system as claimed in claim 5 in which the model utilizes actuator position information.
Claim 8
Dependent Claim
34 words
A process monitoring system as claimed in claim 1 in which the request for additional status information initiates an application of a non-routine test in or to at least one of the SEVA sensors.
Claim 9
Dependent Claim
40 words
A process monitoring system as claimed in claim 1 in which at least some SEVA sensors measure the same variable, and the SEVA measurements (VMV, VU and MV status) of the same variable are combined to generate a best estimate.
Claim 10
Independent Claim
86 words
A method comprising: receiving a first sensor signal from a first sensor monitoring a process, the first sensor being a self-validating (SEVA) sensor; receiving a second sensor signal from a second signal monitoring the process; combining the first sensor signal and the second sensor signal at a control unit to determine apparent status information related to the process; comparing the apparent status information with reference data to obtain comparison information; and obtaining sensor status information related to the first sensor, in response to the comparison information.
Claim 11
Independent Claim
86 words
A method comprising: receiving a first sensor signal from a first sensor monitoring a process, the first sensor being a self-validating (SEVA) sensor; receiving a second sensor signal from a second signal monitoring the process; combining the first sensor signal and the second sensor signal at a control unit to determine apparent status information related to the process; comparing the apparent status information with reference data to obtain comparison information; and obtaining sensor status information related to the first sensor, in response to the comparison information.
Claim 12
Dependent Claim
30 words
The method of claim 9 further comprising distinguishing between a change in a condition of the process and a malfunction of the first sensor, based on the sensor status information.
Claim 13
Dependent Claim
32 words
The method of claim 9 wherein analyzing the first sensor signal and the second sensor signal comprises implementing a multivariate statistical analysis of the first sensor signal and the second sensor signal.
Claim 14
Dependent Claim
28 words
The method of claim 9 wherein the reference data includes a pre-determined model of behavior of the first sensor and the second sensor with respect to the process.
Claim 15
Dependent Claim
21 words
The method of claim 12 wherein the model is based on actuator position signals obtained from actuators involved in the process.
Claim 16
Dependent Claim
28 words
The method of claim 9 wherein the reference data includes historical data describing past behavior of the first sensor and the second sensor with respect to the process.
Claim 17
Independent Claim
89 words
A system comprising: a first sensor operable to output a first measurement of a first variable related to a process; a second sensor operable to output a second measurement of a second variable related to the process; a process monitor having access to sensor reference information and operable to combine the first measurement and second measurement to obtain an apparent process status, and further operable to compare the apparent process status with the sensor reference information so as to distinguish between a sensor malfunction and an actual process status.
Claim 18
Independent Claim
89 words
A system comprising: a first sensor operable to output a first measurement of a first variable related to a process; a second sensor operable to output a second measurement of a second variable related to the process; a process monitor having access to sensor reference information and operable to combine the first measurement and second measurement to obtain an apparent process status, and further operable to compare the apparent process status with the sensor reference information so as to distinguish between a sensor malfunction and an actual process status.
Claim 19
Dependent Claim
25 words
The system of claim 15 wherein the process monitor is operable to analyze the first measurement and the second measurement using a multivariate statistical analysis.
Claim 20
Dependent Claim
18 words
The system of claim 15 wherein the reference information includes a theoretical model of behavior of the process.
Claim 21
Dependent Claim
20 words
The system of claim 17 wherein the theoretical model includes position signals obtained from actuators involved in implementing the process.
Claim 22
Dependent Claim
15 words
The system of claim 15 wherein the reference information includes historical data describing the process.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2007-11-09 | 2008-05-10 | 2008-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2011-11-09 | 2012-05-10 | 2012-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2015-11-09 | 2016-05-10 | 2016-11-09 | $7700.00 | Window Closed / Lapsed |