Patent US6259381B1 successfully refreshed from Google Patents.
EP0152871A2
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Process control apparatus
Assignee: Toshiba Corp
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Filing: 1985-02-07
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Granted: —
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Expires: 2005-02-07
Abstract
Abstract A process control apparatus according to the present invention comprises a feed back control system (44, 46, 48) for outputting a feedback control signal which is computed by comparing and adjusting a set value (SV) and a process variable (PV), and a feedforward control system (56, 58) for outputting a disturbance compensation signal (DK) by detecting and compensating for the disturbance based on the feedforward control model (58). The gain of the feedback control signal is corrected in response to the magnitude of the disturbance variations by the gain scheduling unit (52), and the gain of the feedforward control model is controlled by supplying a correction signal which compares and equalizes, at the feedforward control model gain adaptive unit (60), the disturbance compensation signal and the manipulated variable (MV) obtained by additively synthesizing the disturbance compensation signal and the feedback signal that is gain-corrected by the gain scheduling unit. The feedforward control model (58) comprises a gain memory for memorizing the FF model gain correction signal from the feedforward control model gain adaptive unit (60) and an operational means for receiving a correction signal from the gain memory and a disturbance signal to compute and output a disturbance compensation signal. And, the process control apparatus further includes an FF model gain adaptive mechanism for controlling the supply to the gain memory of the FF model gain correction signal by confirming that the process is in a steady state, the process is settled, and a state continues in which the difference between the disturbance compensation signal and the manipulated quantity exceeds a prescribed value, and for controlling as well the additive synthesis of the disturbance compensation signal to the feedback control signal.
Inventors
- 👤 Kazuo Hiroi
- 👤 Kojiro Ito
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 17:54
CPC Classifications
G; G05; G05B; G05B13/00; G05B13/02; G05B13/04
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
143 words
A process control apparatus which is adapted optimally to a disturbance, comprising: feedback control means (44,46,48) for outputting a feedback control signal that is computed by comparing and adjusting a set value (SV) and a process variable (PV); feedforward control means (56,58) for outputting a disturbance compensation signal (DK) to compensate the disturbance based on a feedforward control model; gain scheduling means (52) for correcting a gain of the feedback control signal in response to the magnitude of the variations in the disturbance; and feedforward control model gain adaptive means (60) for outputting a correction signal to compare and to equalize the manipulated variable (MV), obtained by additively synthesizing the feedback control signal which is gain-controlled by said gain scheduling means (52) and the disturbance compensation signal (DK), with said disturbance compensation signal (DK), to correct the gain of said feedforward control model.
Claim 2
Dependent Claim
143 words
A process control apparatus which is adapted optimally to a disturbance, comprising: feedback control means (44,46,48) for outputting a feedback control signal that is computed by comparing and adjusting a set value (SV) and a process variable (PV); feedforward control means (56,58) for outputting a disturbance compensation signal (DK) to compensate the disturbance based on a feedforward control model; gain scheduling means (52) for correcting a gain of the feedback control signal in response to the magnitude of the variations in the disturbance; and feedforward control model gain adaptive means (60) for outputting a correction signal to compare and to equalize the manipulated variable (MV), obtained by additively synthesizing the feedback control signal which is gain-controlled by said gain scheduling means (52) and the disturbance compensation signal (DK), with said disturbance compensation signal (DK), to correct the gain of said feedforward control model.
Claim 3
Dependent Claim
50 words
A process control apparatus as claimed in claim 1, in which said feedforward control model gain adaptive means (60) corrects the gain of the feedforward control model (58) to bring the feedback control signal of the feedback control means (56,58) to zero at the time of change in the disturbance.
Claim 4
Dependent Claim
58 words
A process control apparatus as claimed in claim 1, in which said gain scheduling means (52) corrects the gain of the feedback control signal by multiplying the feedback control signal with a gain correction signal which is computed by relating the magnitude of the disturbance to a coupling coefficient (C) that is set based on the process variable.
Claim 5
Dependent Claim
28 words
A process control apparatus as claimed in claim 1, in which said feedforward control model gain adaptive means (60) corrects periodically the gain of the feedforward control model.
Claim 6
Dependent Claim
51 words
A process control apparatus as claimed in claim 1, in which said feedforward control model gain adaptive means (60) judges the magnitude of the gain of the feedback control signal or the manipulated variable to correct the gain of the feedforward control model (58) when the gain exceeds a predetermined level.
Claim 7
Dependent Claim
93 words
A process control apparatus as claimed in claim 2, in which said gain scheduling means (52) comprises a gain scheduling unit with the following gain correction signal Y: where, FF is the input signal to the gain scheduling unit, namely, the disturbance compensation signal, Y is its output signal, namely, the gain correction signal coefficient, C is the coupling coefficient between the feedforward control and the feedback control, and Xo is the magnitude of the disturbance compensation signal at the time when the PID parameter of the feedback control adjustment unit is determined.
Claim 8
Dependent Claim
66 words
A process control apparatus as claimed in claim 5, in which said feedforward control model gain adaptive means (60) comprises a feedforward model gain correction unit (62) with the following function: where, Kn-1 is the FF model gain for the preceding time, MVn is the manipulated quantity for the present time, FFn is the FF quantity for the present time, and k is the correction coefficient.
Claim 9
Dependent Claim
27 words
A process control apparatus as claimed in claim 7, in which the correction coefficient k in the feedforward model gain correction unit (61) is equal to unity.
Claim 10
Dependent Claim
27 words
A process control apparatus as claimed in claim 7, in which the correction coefficient k in the feedforward model gain correction unit (61) satisfies a condition o<k£1.
Claim 11
Dependent Claim
63 words
A process control apparatus as claimed in claim 1, in which the feedforward control model (58) comprises a gain memory (64) for memorizing the FF model gain correction signal from said feedforward control model gain adaptive means, and an operations means (65) for receiving the correction signal from the gain memory, and the disturbance signal to compute and output a disturbance compensation signal.
Claim 12
Dependent Claim
84 words
A process control apparatus as claimed in claim 10 further comprising an FF model gain adaptive mechanism (66) for detecting that the process is in a steady state, the control is in a steady state and the difference between the disturbance compensation signal and the manipulated quantity exceeds a predetermined value, to control the supply of the FF model gain correction signal to the gain memory, as well as to control the additive synthesis of the disturbance compensation signal and the feedback control signal.
Claim 13
Dependent Claim
42 words
A process control apparatus as claimed in claim 11, further comprising a dynamic characteristic compensation circuit (78) for receiving the disturbance compensation signal to add the dynamic characteristic compensation signal to the manipulated variable in order to compensate for the dynamic characteristic.
Claim 14
Dependent Claim
133 words
A process control apparatus as claimed in claim 5, in which said feedforward control. model gain adaptive means (60) comprises a sample value control unit (106), a disturbance compensation signal correction system (102) which carries out correction to have the disturbance compensation signal to be equal to the manipulated variable MV * which is outputted to the process, and a correction influence compensation system (104) which compensates for an adverse influence due to the correction on the disturbance compensation signal which is corrected by the disturbance compensation signal correction system, these two systems execute an automatic correction and its compensation operation for the disturbance compensation signal so as to minimize the degree of contribution of the feedback control in the feedforward/feedback control based on the correction signal from the sample value control unit.
Claim 15
Dependent Claim
107 words
A process control apparatus as claimed in claim 13, in which the disturbance compensation signal correction system (102) comprises a first multiplier (110) for multiplying the correction signal from the sample value control unit (106) by the disturbance compensation signal (DK) from the feedforward control model (58), and the correction influence compensation system (104) comprises a second multiplier (114) for multiplying the disturbance compensation signal (DK) from the feedforward control model (58) and the correction signal from the sample value control unit (106), and a compensator (116) for subtracting the influence compensation signal from the second multiplier from the corrected disturbance compensation signal from the first multiplier.
Claim 16
Dependent Claim
275 words
A process control apparatus which is adapted optimally to a disturbance, comprising: feedback control means (44,46,48) for outputting a feedback control signal which is computed by comparing and adjusting a set value (SV) and a process variable (PV); feedforward control means (56,58) for outputting a disturbance compensation signal (DK) to compensate the disturbance based on a feedforward control model; gain scheduling means (52) for correcting a gain of the feedback control signal in response to the magnitude of variations in the disturbance; feedforward control model gain adaptive means (60) for outputting a correction signal to compare and to equalize the manipulated variable (MV) obtained by additively synthesizing the feedback control signal which is gain-controlled by said gain scheduling means (52) and the disturbance compensation singal (DK), with the disturbance compensation signal (DK) to correct the gain of the feedforward control model (58), the feedforward control model (58) comprising a gain memory (64) for memorizing the feedforward model gain correction signal from said feedforward control gain adaptive means (60), and an operational means (65) for receiving the correction signal from the gain memory (64) and the disturbance signal (D), to compute and output a disturbance compensation signal (DK); and feedforward model gain adaptive mechanism (66) for detecting that the process continues to be in a steady state and the control is set, in which the difference between the disturbance compensation signal (DK) and the manipulated variable (MV) exceeds a predetermined value, to control the supply of the feedforward model gain correction signal to the gain memory (64), as well as to control the additive synthesis of the disturbance compensation signal (DK) and the feedback control signal.
Claim 17
Dependent Claim
275 words
A process control apparatus which is adapted optimally to a disturbance, comprising: feedback control means (44,46,48) for outputting a feedback control signal which is computed by comparing and adjusting a set value (SV) and a process variable (PV); feedforward control means (56,58) for outputting a disturbance compensation signal (DK) to compensate the disturbance based on a feedforward control model; gain scheduling means (52) for correcting a gain of the feedback control signal in response to the magnitude of variations in the disturbance; feedforward control model gain adaptive means (60) for outputting a correction signal to compare and to equalize the manipulated variable (MV) obtained by additively synthesizing the feedback control signal which is gain-controlled by said gain scheduling means (52) and the disturbance compensation singal (DK), with the disturbance compensation signal (DK) to correct the gain of the feedforward control model (58), the feedforward control model (58) comprising a gain memory (64) for memorizing the feedforward model gain correction signal from said feedforward control gain adaptive means (60), and an operational means (65) for receiving the correction signal from the gain memory (64) and the disturbance signal (D), to compute and output a disturbance compensation signal (DK); and feedforward model gain adaptive mechanism (66) for detecting that the process continues to be in a steady state and the control is set, in which the difference between the disturbance compensation signal (DK) and the manipulated variable (MV) exceeds a predetermined value, to control the supply of the feedforward model gain correction signal to the gain memory (64), as well as to control the additive synthesis of the disturbance compensation signal (DK) and the feedback control signal.
Claim 18
Dependent Claim
93 words
A process control apparatus as claimed in claim 15, in which the gain scheduling means (52) comprises a gain scheduling unit with the following gain correction signal Y: where, FF is the input signal to the gain scheduling unit, namely, the disturbance compensation signal, Y is its output signal, namely, the gain correction signal coefficient, C is the coupling coefficient between the FF control and the FB control, and Xo is the magnitude of the disturbance compensation signal at the time when the PID parameter of the FB control adjustment unit is determined.
Claim 19
Dependent Claim
66 words
A process control apparatus as claimed in claim 16, in which said feedforward control model gain adaptive means (60) comprises a feedforward model gain correction unit (62) with the following function: where, Kn-1 is the FF model gain for the preceding time, MVn is the manipulated quantity for the present time, FFn is the FF quantity for the present time, and k is the correction coefficient.
Claim 20
Dependent Claim
26 words
A process control apparatus as claimed in claim 17, in which the correction coefficient k in the feedforward model gain correction unit is equal to unity.
Claim 21
Dependent Claim
26 words
A process control apparatus as claimed in claim 17, in which the correction coefficient k in the feedforward model gain correction unit satisfies a condition 0<k<l.
Claim 22
Dependent Claim
122 words
A process control method for adapting optimally to a disturbance (D), comprising the steps of: supplying a feedback control signal that is computed by comparing and adjusting a set value (SV) and a process variable (PV); supplying a disturbance compensation signal (DK) to compensate the disturbance ( D ) based on a feedforward control model (58); correcting a gain of the feedback control signal in response to the magnitude of the variations in the disturbance (D); and supplying a correction signal to compare and to equalize the manipulated variable (MV) obtained by additively synthesizing the feedback control signal which is gain-controlled and the disturbance compensation signal (DK), with said disturbance compensation signal (DK), to correct the gain of said feedforward control model.
Claim 23
Dependent Claim
122 words
A process control method for adapting optimally to a disturbance (D), comprising the steps of: supplying a feedback control signal that is computed by comparing and adjusting a set value (SV) and a process variable (PV); supplying a disturbance compensation signal (DK) to compensate the disturbance ( D ) based on a feedforward control model (58); correcting a gain of the feedback control signal in response to the magnitude of the variations in the disturbance (D); and supplying a correction signal to compare and to equalize the manipulated variable (MV) obtained by additively synthesizing the feedback control signal which is gain-controlled and the disturbance compensation signal (DK), with said disturbance compensation signal (DK), to correct the gain of said feedforward control model.
Claim 24
Dependent Claim
37 words
A process control method as claimed in claim 20, in which the gain of the feedforward control model (58) is corrected to bring the feedback control signal to zero at the time of change in the disturbance.
Claim 25
Dependent Claim
53 words
A process control method as claimed in claim 20, in which the gain of the feedback control signal is corrected by multiplying the feedback control signal with a gain correction signal which is computed by relating the magnitude of the disturbance to a coupling coefficient that is set based on the process variable.
Claim 26
Dependent Claim
21 words
A process control method as claimed in claim 20, in which the gain of the feedforward control model is corrected periodically.
Claim 27
Dependent Claim
43 words
A process control method as claimed in claim 20, in which the magnitude of the gain of the feedback control signal or the manipulated signal is judged to correct the gain of the feedforward control model when the gain exceeds a predetermined level.
Claim 28
Dependent Claim
112 words
A process control method as claimed in claim 21, in which gain scheduling means for correcting a gain of the feedback control signal in response to the magnitude of the variations in the disturbance comprises a gain scheduling unit with the following gain correction signal Y: where, FF is the input signal to the gain scheduling unit, namely, the disturbance compensation signal, Y is its output signal, namely, the gain correction signal coefficient, C is the coupling coefficient between the feedforward control and the feedback control, and X o is the magnitude of the disturbance compensation signal at the time when the PID parameter of the feedback control adjustment unit is determined.
Claim 29
Dependent Claim
83 words
A process control method as claimed in claim 24, in which feedforward control model gain adaptive means (60) for supplying a correction signal to compare and equalize the manipulated signal with the disturbance compensation signal comprises a feedforward model gain correction unit (62) with the following function: where, Kn-1 is the F F model gain for the preceding time, MVn is the manipulated quantity for the present time, FFn is the FF quantity for the present time, and k is the correction coefficient.
Claim 30
Dependent Claim
233 words
A process control method for adapting optimally to a disturbance (D), comprising the steps of: outputting a feedback control signal which is computed by comparing and adjusting a set value (SV) and a process variable (PV); supplying a disturbance compensation signal (DK) to compensate the disturbance based on a feedforward control model (58); correcting a gain of the feedback control signal in response to the magnitude of variations in the disturbance; supplying a correction signal to compare and to equalize the manipulated variable (MV) obtained by additively synthesizing the feedback control signal which is gain-controlled and the disturbance compensation signal (DK), with the disturbance compensation signal to correct the gain of the feedforward control model (58), the feedforward control model (58) comprising a gain memory (64) for memorizing the feedforward model gain correction signal and an operational means (65) for receiving the correction signal from the gain memory (64) and the disturbance signal (D), to compute and output a disturbance compensation signal (DK); and detecting that the process continues to be in a steady state and the control is set, in which the difference between the disturbance compensation signal and the manipulated quality exceeds a predetermined value, to control the supply of the feedforward model gain correction signal to ' the gain memory (64), as well as to control the additive synthesis of the disturbance compensation signal (DK) and the feedback control signal.
Claim 31
Dependent Claim
233 words
A process control method for adapting optimally to a disturbance (D), comprising the steps of: outputting a feedback control signal which is computed by comparing and adjusting a set value (SV) and a process variable (PV); supplying a disturbance compensation signal (DK) to compensate the disturbance based on a feedforward control model (58); correcting a gain of the feedback control signal in response to the magnitude of variations in the disturbance; supplying a correction signal to compare and to equalize the manipulated variable (MV) obtained by additively synthesizing the feedback control signal which is gain-controlled and the disturbance compensation signal (DK), with the disturbance compensation signal to correct the gain of the feedforward control model (58), the feedforward control model (58) comprising a gain memory (64) for memorizing the feedforward model gain correction signal and an operational means (65) for receiving the correction signal from the gain memory (64) and the disturbance signal (D), to compute and output a disturbance compensation signal (DK); and detecting that the process continues to be in a steady state and the control is set, in which the difference between the disturbance compensation signal and the manipulated quality exceeds a predetermined value, to control the supply of the feedforward model gain correction signal to ' the gain memory (64), as well as to control the additive synthesis of the disturbance compensation signal (DK) and the feedback control signal.
Claim 32
Dependent Claim
112 words
A process control method as claimed in claim 27, in which gain scheduling means (52) for correcting a gain of the feedback control signal in response to the magnitude of the variations in the disturbance comprises a gain scheduling unit with the following gain correction signal Y: where, FF is the input signal to the gain scheduling unit, namely, the disturbance compensation signal, Y is its output signal, namely, the gain correction signal coefficient, C is the coupling coefficient between the FF control and the FB control, and Xo is the magnitude of the disturbance compensation signal at the time when the PID parameter of the FB control adjustment unit is determined.
Claim 33
Dependent Claim
83 words
A process control method as claimed in claim 28, in which feedforward control model gain adaptive means (60) for supplying a correction signal to compare and equalize the manipulated signal with the disturbance compensation signal means comprises a feedforward model gain correction unit (62) with the following function: where, Kn-1 is the FF model gain for the preceding time, MVn is the manipulated quantity for the present time, FFn is the FF quantity for the present time, and k is the correction coefficient.
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