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US4908747A
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Advanced proportional plus integral plus derivative controller
Assignee: ABB Technology AG
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Filing: 1988-03-21
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Granted: 1990-03-13
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Expires: 2008-03-21
Abstract
Abstract A proportional plus integral plus differential (PID) controller containing an algorithm option is disclosed. The option allows the selection of a classical interacting type of controller or a non-interacting type of controller. The classical interacting type of controller is characterized by the property that tuning any one of the proportional, integral or derivative terms changes the effective value of the other terms. In contrast, the non-interacting type of controller is characterized by the property that tuning any one of the proportional, integral or derivative terms has no effect on the other terms.
Inventors
- 👤 John D. Lane
- 👤 Theodore N. Matsko
- 👤 Joseph G. Patella
- 👤 Thomas J. Scheib
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:10
CPC Classifications
G; G05; G05B; G05B11/00; G05B11/01; G05B11/36; G05B11/42
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
162 words
Apparatus for producing an interacting proportional, derivative, and integral process control signal from a process variable signal or a proportional, derivative and external reset signal from a process variable signal comprising: means for converting the process variable signal into a first signal which is proportional to said process variable signal; means for converting the process variable signal into a second signal which is a function of the derivative of said process variable signal; means for converting the process variable signal into a third signal which is a function of the integral of said process variable signal; means for combining said first, second and third signals to produce said process control signal; switch means for removing said third signal from said combining means and replacing third signal with an external reset signal; and wherein variation of any one of said first, second and third signals causes a variation in the remainder of said first, second and third signals as per an interacting algorithm.
Claim 2
Dependent Claim
162 words
Apparatus for producing an interacting proportional, derivative, and integral process control signal from a process variable signal or a proportional, derivative and external reset signal from a process variable signal comprising: means for converting the process variable signal into a first signal which is proportional to said process variable signal; means for converting the process variable signal into a second signal which is a function of the derivative of said process variable signal; means for converting the process variable signal into a third signal which is a function of the integral of said process variable signal; means for combining said first, second and third signals to produce said process control signal; switch means for removing said third signal from said combining means and replacing third signal with an external reset signal; and wherein variation of any one of said first, second and third signals causes a variation in the remainder of said first, second and third signals as per an interacting algorithm.
Claim 3
Dependent Claim
26 words
The apparatus as defined in claim 1 wherein said process variable signal converting means that produces said first signal comprises an algorithm in the Laplace domain.
Claim 4
Dependent Claim
18 words
The apparatus as defined in claim 2 wherein said algorithm in the Laplace domain is kk p .
Claim 5
Dependent Claim
26 words
The apparatus as defined in claim 1 wherein said process variable signal converting means that produces said second signal comprises an algorithm in the Laplace domain.
Claim 6
Dependent Claim
15 words
The apparatus of claim 4 wherein said algorithm in the Laplace domain is: ##EQU3## .
Claim 7
Dependent Claim
26 words
The apparatus as defined in claim 1 wherein said process variable signal converting means that produces said third signal comprises an algorithm in the Laplace domain.
Claim 8
Dependent Claim
18 words
The apparatus as defined in claim 6 wherein said algorithm in the Laplace domain is 60k i /S.
Claim 9
Dependent Claim
18 words
The apparatus as defined in claim 6 wherein said algorithm in the Laplace domain is kk i /S.
Claim 10
Dependent Claim
157 words
Apparatus for producing a non-interactive proportional, derivative, and integral process control signal from a process variable signal comprising: means for converting the process variable signal into a first signal which is proportional to said process variable signal; means for converting the process variable signal into a second signal which is a function of the derivative of said process variable signal wherein said process variable signal converting means produces said second signal as an algorithm in the the Laplace domain as follows: ##EQU4## means for converting the process variable signal into a third signal which is a function of the integral of said process variable signal; means for combining said first, second and third signals to produce said process control signal; and wherein variation of any one of said first, second and third signals results in those of said first, second and third signals which have not been varied remaining constant as per a non-interactive PID controls algorithm.
Claim 11
Dependent Claim
157 words
Apparatus for producing a non-interactive proportional, derivative, and integral process control signal from a process variable signal comprising: means for converting the process variable signal into a first signal which is proportional to said process variable signal; means for converting the process variable signal into a second signal which is a function of the derivative of said process variable signal wherein said process variable signal converting means produces said second signal as an algorithm in the the Laplace domain as follows: ##EQU4## means for converting the process variable signal into a third signal which is a function of the integral of said process variable signal; means for combining said first, second and third signals to produce said process control signal; and wherein variation of any one of said first, second and third signals results in those of said first, second and third signals which have not been varied remaining constant as per a non-interactive PID controls algorithm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-12 | 1993-09-11 | 1994-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-12 | 1997-09-11 | 1998-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-12 | 2001-09-11 | 2002-03-13 | $7700.00 | Window Closed / Lapsed |