JPH10143205A - Sac controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To unnecessitate special knowledge for control and the time and labor for adjustment in the operation of an adaptive control system. SOLUTION: A parallel feedforward compensation(PFC) operating part 5 performs PFC operation to a manipulated variable u(k), and a standard model operating part 3 performs standard model operation to a set value sp(k). According to a simple adaptive control(SAC) algorithm, a manipulated variable calculating part 4 calculates the manipulated variable u(k) from a controlled variable y(k), set value sp(k) and the outputs of operation parts 3 and 5. Based on a process gain stored in a process storage part 7, a PFC control part 8 automatically controls the PFC gain of the PFC operating part 5. Based on the process gain, a SAC control part 9 automatically controls the SAC gain of the manipulated variable calculating part 4. Only by storing the value of the real process gain in the storage part 7, suitable control characteristics are maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a SAC control.
It is about LA.

[0002]

2. Description of the Related Art In the early 1980's, the basic form of an adaptive control system was determined, and the boundedness of the signal within the adaptive loop and the asymptotic stability of the output error were theoretically proved. However, it has been pointed out that the control algorithm is complicated, contains many parameters to be set in practical use, and furthermore, there is no clear guideline for adjusting these parameters.
Therefore, SAC (Simple Adaptive Control) has been studied as a solution to such a problem (Literature: Iwai, "Simple Adaptive Control (SAC)", Measurement and Control,
Vol. 35, No. 6, 1996).

[0003] SAC was established in 1982 by Sobel.
), A method proposed by Kaufman and Mabius, and subsequently studied by Bar-Kana et al. This method adaptively realizes an ideal control input (operating amount) such that the control amount matches the reference model output, and at the same time, secures the stability of the closed loop system in an adaptive output feedback form. CGT
(Command Generator tracker).

[0004] As a precondition that this SAC can be configured,
The control target is ASPR (Almost Strictly Positive Real
) It is necessary to satisfy the conditions. In conclusion,
If the control target process includes a dead time, the ASPR condition is not satisfied. Therefore, as a technique for satisfying the ASPR condition, parallel feedforward compensation (Parallel
Feedforward Compensator (hereinafter abbreviated as PFC) has been proposed. If this PFC is simply expressed, it is a method of adding an appropriate pseudo response to the measured value of the control amount in order to fake apparently that there is no response for the dead time of the control target.

FIG. 15 is a block diagram of a control system using such a conventional SAC controller. The SAC controller includes a reference model calculation unit 33 and an operation amount calculation unit 3
4. PFC operation unit 35. First, the PFC calculator 35 calculates the output value yf (k) as follows. zf (k) = [b1 × zf (k−1) + Kf × {u (k−1) −u (k−2)}] / (b1 + dT) (1) yf (k) = ｛b2 × yf (k−1) + dT × zf (k)｝ / (b2 + dT) (2)

In equations (1) and (2), zf (k) is an internal variable, zf (k-1) is a value of the internal variable zf (k) one control cycle before, and yf (k-1) is an output. 1 of the value yf (k)
The values before the control cycle, u (k−1) and u (k−2), are the values of the manipulated variable u (k) output from the manipulated variable calculation unit 34 one and two control cycles before, respectively. DT is a control cycle parameter, b1 and b2 are constants, and Kf is a PFC gain. Subsequently, the reference model calculator 33 sets the set value sp
From (k) to output values z _n-1 (k), z _n-2 (k) ... z ₁
(K) and z ₀ (k) are calculated as in the following equations.

[0007] In equation (3), z _n-1 (k-1), z _n-2 (k-1)
... z ₁ (k-1) and z ₀ (k-1) are output values z _n-1 (k) and z _n-2 (k) ... z ₁ (k) and z _{0, respectively.}
One control period previous value of _{(k), a m, a} 0, a 1 ··· a
_n-2 and a _n-1 are constants.

Next, the manipulated variable calculator 34 calculates the manipulated variable u (k) as follows. First, the addition unit 41 in the operation amount calculation unit 34 adds the control amount y (k) of the control target process 50 and the output value yf (k) of the PFC operation unit 35, and further, the subtraction unit 42 adds The output value z ₀ (k) of the reference model calculation unit 33 is subtracted from the output of. Therefore,
The output value ey (k) of the subtractor 42 is given by the following equation. ey (k) = y (k ) + yf (k) -z 0 (k) ··· (4)

The operation units 43 to 45 output the output value K _P1
(K), K _P2 (k) ... K _{Pn + 2} (k), K _J1 (k),
K _J2 (k)... K _{Jn + 2} (k) are calculated as follows.

[0010]

In equations (5) and (6), K _J1 (k−
_{1), K J2 (k-} 1) ··· K Jn + 2 (k-1) each output value K _J1 (k), 1 control _{K J2 (k) ··· K Jn} + 2 (k) Values before the cycle, γ _P1 , γ _P2 ... γ _Pn , γ _{Pn + 1} , γ
_{Pn + 2} , γ _J1 , γ _J2 ... γ _Jn , γ _{Jn + 1} , γ _{Jn + 2} are SAC
Gain. In addition, among the outputs of the arithmetic units 43 to 45,
The calculation unit 45 calculates K _P1 and K _J1 , and calculates K _P2 and K _P3.
... K _{Pn + 1} , K _J2 , K _J3 ... K _{Jn + 1} are calculated by the calculation unit 44, and K _{Pn + 2} , K _{Jn + 2} are calculated by the calculation unit 43.
Is calculated. Lastly, the adder 46 adds the outputs of the calculator 43 and the calculator 44, and the adder 47 further adds
And the output of the arithmetic unit 45 are added. As a result, the output of the adder 47 is the operation amount u which is the output of the operation amount calculator 34.
(K).

U (k) = ｛K _P1 (k) + K _J1 (k)｝ × ey (k) + ｛K _P2 (k) + K _J2 (k)｝ × z ₀ (k) + ｛K _P3 (k ) + K _J3 (k)｝ × z ₁ (k): + ｛K _Pn (k) + K _Jn (k)｝ × z _n-2 (k) + ｛K _{Pn + 1} (k) + K _{Jn + 1} (k ) × z _n−1 (k) + {K _{Pn + 2} (k) + K _{Jn + 2} (k)} × sp (k) (7) The above SAC controller is an adaptive control method. Although it is a simple class inside, the parameters to be adjusted still
There are 10 or more parameters, which are adjusted based on highly specialized knowledge.

[0013]

As described above, the conventional S
Since the AC controller is designed and adjusted based on extremely specialized knowledge, there has been a problem that an operator without specialized control knowledge cannot use the controller as a general-purpose controller. In addition, if incorrect parameters are set, not only the control characteristics are degraded, but also there is a problem that the control target may fall into an extremely abnormal and dangerous state. SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a SAC controller that does not require expert knowledge of control and trouble of adjustment.

[0014]

According to a first aspect of the present invention, there is provided a PFC operation unit for performing a parallel feedforward compensation operation on an operation amount based on a PFC gain, and a reference model for a set value. By a reference model calculation unit for performing calculation and a SAC algorithm based on SAC gain,
An operation amount calculation unit that calculates an operation amount from a control amount, a set value, an output of a PFC operation unit and an output of a reference model operation unit, and outputs the operation amount to the PFC operation unit and a process to be controlled, and a process for storing a gain of the process to be controlled A storage unit, a PFC adjustment unit that calculates a correction value of the PFC gain from the process gain stored in the process storage unit, and changes the PFC gain of the PFC calculation unit to the correction value; and a PFC adjustment unit that stores the correction value. A SAC adjustment unit that calculates a correction value of the SAC gain from the process gain and changes the SAC gain of the operation amount calculation unit to the correction value. As described above, the PFC operation unit performs the parallel feedforward compensation operation on the operation amount, the reference model operation unit performs the reference model operation on the set value, and the operation amount calculation unit performs the control amount, the set value, and the PFC operation using the SAC algorithm. The control target process is controlled by calculating the operation amount from the output of the unit and the reference model calculation unit and outputting the manipulated variable to the PFC calculation unit and the control target process. Then, in order to realize appropriate control characteristics, the PFC gain of the PFC calculation unit is automatically adjusted by the PFC adjustment unit that calculates a correction value of the PFC gain from the process gain stored in the process storage unit,
The SAC gain of the manipulated variable calculator is calculated from the process gain by S
It is automatically adjusted by the SAC adjustment unit that calculates the correction value of the AC gain.

[0015] According to a second aspect of the present invention, there is provided a PFC operation unit for performing a parallel feedforward compensation operation on an operation amount based on a PFC gain and a control cycle parameter.
A reference model calculation unit for performing a reference model calculation on the input set value based on the control cycle parameter, and a control amount, a set value, a PFC calculation unit, and a reference model calculation unit using a SAC algorithm based on the SAC gain and the control cycle parameter An operation amount calculation unit that calculates an operation amount from the output of the PFC operation unit and outputs the operation amount to the control target process, a process storage unit that stores a dead time of the control target process,
A cycle adjustment unit that calculates a correction value of the control cycle parameter from the process dead time stored in the process storage unit, and changes the control cycle parameters of the PFC calculation unit, the reference model calculation unit, and the operation amount calculation unit to the correction value. And In order to realize an appropriate control characteristic as described above, the control cycle parameter of the PFC calculation unit, the reference model calculation unit, and the operation amount calculation unit calculates a correction value of the control cycle parameter from the process dead time stored in the process storage unit. It is automatically adjusted by the calculated period adjustment unit.

According to a third aspect of the present invention, there is provided a PFC operation unit for performing a parallel feedforward compensation operation on an operation amount based on a PFC gain, and a reference model for performing a reference model operation on an input set value. An operation amount calculation unit that calculates an operation amount from a control amount, a set value, an output of the PFC operation unit and an output of the reference model operation unit, and outputs the operation amount to the PFC operation unit by a SAC algorithm based on the SAC gain;
A process storage unit for storing the time constant of the process to be controlled, and a lead lag compensation calculation for the operation amount output from the operation amount calculation unit based on the process time constant stored in the process storage unit; And a lead lag compensating unit that outputs the value as an operation amount to the process to be controlled. In order to realize appropriate control characteristics as described above, the lead lag compensation unit performs a lead lag compensation operation on the operation amount output from the operation amount calculation unit based on the process time constant stored in the process storage unit. The calculation result is output as a manipulated variable to the process to be controlled.

A PFC operation unit for performing a parallel feedforward compensation operation on an operation amount based on a PFC gain and a control cycle parameter, as described in claim 4,
A reference model calculation unit for performing a reference model calculation on the input set value based on the control cycle parameter, and a control amount, a set value, a PFC calculation unit, and a reference model calculation unit using a SAC algorithm based on the SAC gain and the control cycle parameter The operation amount calculation unit that calculates the operation amount from the output of the control unit and outputs the operation amount to the PFC operation unit, the process storage unit for storing the gain, the time constant, and the dead time of the control target process, and the operation amount calculation unit A lead-lag compensation unit for performing a lead-lag compensation operation on the operation amount based on the process time constant stored in the process storage unit, and outputting the operation result as an operation amount to the process to be controlled; and a process stored in the process storage unit. A PFC gain for calculating a correction value of the PFC gain from the gain and changing the PFC gain of the PFC calculation unit to the correction value. SA in which the parts, from the process gain stored in the process storage unit calculates a correction value of the SAC gain, changes the SAC gain control input calculation unit to the correction values
A correction value of the control cycle parameter is calculated from the C adjustment unit and the process dead time stored in the process storage unit.
It has a C adjustment unit, a reference model calculation unit, an operation amount calculation unit, and a cycle adjustment unit that changes the control cycle parameter of the lead lag compensation unit to this corrected value. In order to realize such an appropriate control characteristic, the lead-lag compensating unit performs lead-lag compensating calculation on the manipulated variable based on the process time constant, and the PFC adjusting unit performs the Plag adjustment based on the process gain.
The PFC gain of the FC calculation unit is automatically adjusted, and the SAC adjustment unit adjusts the SA of the operation amount calculation unit based on the process gain.
The C gain is automatically adjusted, and the cycle adjustment unit automatically adjusts the control cycle parameters of the PFC calculation unit, the reference model calculation unit, the operation amount calculation unit, and the lead lag compensation unit based on the process dead time.

[0018] According to a fifth aspect of the present invention, there is provided a PFC operation section for performing a parallel feedforward compensation operation on an operation amount based on a PFC gain and a control cycle parameter.
A reference model calculation unit for performing a reference model calculation on the input set value based on the control cycle parameter, and a control amount, a set value, a PFC calculation unit, and a reference model calculation unit using a SAC algorithm based on the SAC gain and the control cycle parameter A manipulated variable calculation unit that calculates a manipulated variable from the output of the PFC calculation unit and outputs the calculated manipulated variable to the PFC calculation unit, and a PID suitable for the process to be controlled.
A PID storage unit for storing parameters, a parameter conversion unit for calculating an estimated value of a gain, a time constant, and a dead time of a process to be controlled from the PID parameters; and an operation amount output from the operation amount calculation unit. On the other hand, a lead-lag compensation calculation is performed based on the process time constant calculated by the parameter conversion unit, and a lead-lag compensation unit that outputs the calculation result as an operation amount to the control target process, and a PFC based on the process gain calculated by the parameter conversion unit A PFC adjustment unit that calculates a correction value of the gain and changes the PFC gain of the PFC calculation unit to this correction value, and calculates a correction value of the SAC gain from the process gain calculated by the parameter conversion unit, and calculates an operation amount. A SAC adjustment unit that changes the SAC gain of the unit to this correction value, and a process waste calculated by the parameter conversion unit. And a cycle adjusting unit that calculates a correction value of the control cycle parameter from the interval, and changes the control cycle parameter of the PFC calculation unit, the reference model calculation unit, the operation amount calculation unit, and the lead lag compensation unit to the correction value. . In order to realize appropriate control characteristics as described above, the parameter conversion unit calculates an estimated value of the gain, the time constant, and the dead time of the process to be controlled from the PID parameters. The lead lag compensation calculation is performed based on the constant, the PFC adjustment unit automatically adjusts the PFC gain of the PFC calculation unit from the process gain, and the SAC adjustment unit automatically adjusts the SAC gain of the operation amount calculation unit from the process gain. Adjustment, the cycle adjustment unit
The control cycle parameters of the PFC calculation unit, the reference model calculation unit, the operation amount calculation unit, and the lead lag compensation unit are automatically adjusted from the process dead time.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

1. Embodiment 1. FIG. 1 is a block diagram of a SAC controller showing a first embodiment of the present invention, and FIG.
FIG. 3 is a block diagram of a control system using a controller, and FIG. 3 is a flowchart for explaining the operation of the controller. FIG. 2 shows the basic configuration of the SAC controller including the reference model calculation unit 3, the operation amount calculation unit 4, and the PFC calculation unit 5 in FIG. 1 rewritten as a control system including the control target process 50.

In the controller of this embodiment,
The PFC adjustment unit 8 determines the PFC gain of the PFC calculation unit 5, and the SAC adjustment unit 9 determines the PFC gain of the operation amount calculation unit 4.
The gain is determined, and the characteristics of the control system are thereby determined. Here, the operation of the controller as the control system will be described first. The set value sp (k) is set by the operator of the controller, and is input to the reference model calculator 3 and the manipulated variable calculator 4 via the set value input unit 1 serving as an interface with the outside (step 104 in FIG. 3). ).

A control amount y (k) is input to the control amount input unit 2 also serving as an interface from the control target process 50 (actually, a sensor for detecting the control amount) (step 105). Next, the PFC calculation unit 5 calculates the output value yf (k) from the operation amount output from the operation amount calculation unit 4.
Is performed, and its transfer function Gf can be expressed as in the following equation.

Gf = Kf × Tf × s / (1 + Tf × s) ² (8) where Kf is a PFC gain and Tf is a time constant. FIG. 4 shows a response characteristic of the PFC calculation unit 5 to the unit step input 1 / s. The response output yf (k) shows a local maximum value at time Tf, and this local maximum value yf (Tf) becomes Kf / e (e is 2.7182...). As described above, the PFC calculation unit 5 outputs yf (k), which is an appropriate pseudo response to be added to the control amount y (k).

The PFC operation unit 5 actually operates as follows in order to realize the PFC operation represented by the transfer function Gf of the continuous time system of the equation (8) in the discrete time system. At first,
The PFC operation unit 5 calculates an internal variable zf (k) as in the following equation. zf (k) = [b1 × zf (k−1) + Kf × {u (k−1) −u (k−2)}] / (b1 + dT) (9) Subsequently, the PFC operation unit 5 , The output value yf as
(K) is calculated. yf (k) = {b2 × yf (k−1) + dT × zf (k)} / (b2 + dT) (10)

In equations (9) and (10), zf (k−
1) is the value of the internal variable zf (k) one control cycle before, yf
(K-1) is a value one control cycle before the output value yf (k), u
(K−1) and u (k−2) are the values of the manipulated variable u (k) output from the manipulated variable calculator 4 before and after the first and second control cycles, respectively,
dT is a control cycle parameter (the same value as the control cycle in the present embodiment), and b1 and b2 are constants corresponding to the time constant Tf. Thus, the PFC operation unit 5 performs the PFC operation (Step 106).

Next, the reference model embodies ideal characteristics of a control system in which the SAC controller and the control target process 50 are integrated, and the characteristics of the control system match the characteristics of the reference model. The controller parameters are adjusted. The reference model calculation unit 3 performs a reference model calculation as the reference model, and calculates the output of the set value sp (k) input from the set value input unit 1 using Expression (3) (Step 107). .

Subsequently, the manipulated variable calculator 4 calculates the manipulated variable u (k) as follows. First, the operation amount calculation unit 4
The adder 21 in the parentheses indicates the control amount y of the process 50 to be controlled.
(K) and the output value yf (k) of the PFC calculation unit 5 are added,
Further, the subtraction unit 22 subtracts the output value z ₀ (k) of the reference model calculation unit 3 from the output of the addition unit 21. Therefore, the output value ey (k) of the subtraction unit 22 is expressed by the following equation. ey (k) = y (k ) + yf (k) -z 0 (k) ··· (11)

The operation units 23 to 25 output the output value K _P1
(K), K _P2 (k) ... K _{Pn + 2} (k), K _J1 (k),
K _J2 (k)... K _{Jn + 2} (k) are calculated as follows.

[0028]

In equations (12) and (13), K _J1 (k
_{-1), K J2 (k-} 1) ··· K Jn +2 (k-1) output value K _J1, respectively _{(k), K J2 (k} ) ··· K Jn + 2 (k)
Γ _P1 , γ _P2 ... Γ _Pn , γ _{Pn + 1} ,
γ _{Pn + 2} , γ _J1 , γ _J2 ... γ _Jn , γ _{Jn + 1} , γ _{Jn + 2} are SA
C gain. Note that among the outputs of the calculation units 23 to 25, K _P1 and K _J1 are calculated by the calculation unit 25, and K _P2 ,
K _P3 ... K _{Pn + 1} , K _J2 , K _J3 ... K _{Jn + 1} are calculated by the calculation unit 24, and K _{Pn + 2} and K _{Jn + 2} are calculated by the calculation unit 23.

Finally, the adder 26 adds the outputs of the calculator 23 and the calculator 24, and the adder 27 further adds
And the output of the operation unit 25 are added. As a result, the output of the addition unit 27 is the operation amount u which is the output of the operation amount calculation unit 4.
(K).

U (k) = {K _P1 (k) + K _J1 (k)} × ey (k) + ｛K _P2 (k) + K _J2 (k)｝ × z ₀ (k) + ｛K _P3 (k ) + K _J3 (k)｝ × z ₁ (k) _:: + ｛K _Pn (k) + K _Jn (k)｝ × z _n-2 (k) + ｛K _{Pn + 1} (k) + K _{Jn + 1} ( k)｝ × z _n-1 (k) + ｛K _{Pn + 2} (k) + K _{Jn + 2} (k)｝ × sp (k) (14)

As described above, the manipulated variable calculator 4 calculates the manipulated variable u (k) (step 108). The operation amount u (k) is output to the control target process 50 (actually, an operation device such as a valve) via the operation amount output unit 6 serving as an interface with the outside (step 109). The operations of Steps 101 to 103 and the operations of Steps 104 to 109 described above are repeated for each control cycle until the controller is stopped by an instruction from the operator or the like (Step 110). This is the operation of the SAC controller.

Next, the operation of the PFC adjustment unit 8 and the SAC adjustment unit 9 will be described. Now, assuming that the control target process has elements of first-order delay and dead time, its transfer function Gp
Can be expressed by the following approximate transfer function. Gp = Kp × exp (−Lp × s) / (1 + Tp × s) (15) In equation (15), Kp is a process gain, Tp is a process time constant, and Lp is a process dead time.

The SAC controller of the present embodiment is adjusted in accordance with the process to be controlled having such first-order delay and dead time elements. Here, the process gain Kp is 1, the process time constant is Tp is 20 seconds,
The process is adjusted in accordance with a process in which the process dead time Lp is 20 seconds (such a control target process is hereinafter referred to as a standard process).

As a result, the above parameter is calculated by Kf =
35.45, b1 = b2 = 12.66, n = 1, a m =
a ₀ = 1 / (12.0 + dT), γ (= γ _P1 = γ _P2 = γ
_P3 = γ _J1 = γ _J2 = γ _J3 ) = 0.025

Therefore, the equation (9) used in the PFC operation unit 5 is set as follows according to the above standard process. zf (k) = [12.66 × zf (k−1) + Kf × {u (k−1) −u (k−2)}] / (12.66 + dT) (16) 10) is set as in the following equation. yf (k) = {12.66 × yf (k−1) + dT × zf (k)} / (12.66 + dT) (17)

The equation (3) used in the reference model calculation unit 3 is set as follows. ym (k) = z ₀ (k) = {12.0 × ym (k−1) + dT × sp (k)} / (12.0 + dT) (18) Expression used in the operation amount calculation unit 4 (12) is set as in the following equation.

Equation (13) is set as follows.

Equation (14) is set as follows. u (k) = ｛K _P1 (k) + K _J1 (k)｝ × ey (k) + ｛K _P2 (k) + K _J2 (k)｝ × ym (k) + ｛K _P3 (k) + K _J3 ( k)｝ × sp (k) (21)

The SAC controller adjusted as described above correctly adjusts the controlled process 50 having an arbitrary process gain (in the present embodiment, the process time constant and the process dead time are the same as those of the standard process). There is no control. Therefore, the SAC adjusting unit 9 calculates the correction value γ1 of the SAC gain according to the control target process 50 as in the following equation. γ1 = γ / Kp1 (22) Kp1 is an estimated value of the process gain of the process 50 to be controlled.

Here, the reason why the correction value γ1 of the SAC gain can be calculated as in equation (22) will be described. For example,
Assuming that the manipulated variable u ′ (k) is output for the standard process in order to obtain an ideal response, the standard process 2 ′
If the manipulated variable u '(k) / 2 is output for a process having a double process gain, the same ideal response can be obtained. In order to output the manipulated variable u ′ (k) / 2, the SAC gain γ adjusted according to the standard process may be corrected to γ / 2. Equation (22) above generalizes such a concept.

Similarly, the PFC adjuster 8 calculates a correction value Kf1 of the PFC gain according to the process 50 to be controlled as in the following equation. Kf1 = Kf × Kp1 (23)

Here, the reason why the correction value Kf1 of the PFC gain can be calculated as in equation (23) will be described. For example,
In order to obtain an ideal response, the manipulated variable u ′ (k) is output to the PFC calculation unit 5 and the standard process adjusted to the standard process, and as a result, the output yf ′ (k) is output from the PFC calculation unit 5 Is output. At this time, if the SAC gain of the manipulated variable calculator 4 is corrected as described above,
The output of the PFC operation unit 5 becomes yf ′ (k) × Kp1. Therefore, P adjusted to the standard process
If the FC gain Kf is corrected to Kf × Kp1, the output of the PFC calculation unit 5 is maintained at yf ′ (k).

The process storage unit 7 stores an estimated value Kp1, a process time constant Tp1, and an estimated process dead time Lp1 of the process gain of the process 50 to be controlled set by the operator. In this embodiment, since only Kp1 is used, only Kp1 needs to be set.

The PFC adjustment unit 8 and the SAC adjustment unit 9 read the estimated process gain Kp1 from the process storage unit 7 (Step 101 in FIG. 3). Then, the PFC adjustment unit 8 calculates the correction value Kf1 of the PFC gain by the equation (23).
Is calculated and output to the PFC calculation unit 5. Accordingly, the PFC gain Kf of the PFC calculation unit 5 (Equation (16))
Is changed to the correction value Kf1 (step 102).

Subsequently, the SAC adjuster 9 calculates the correction value γ1 of the SAC gain by the equation (22), and outputs this to the manipulated variable calculator 4. Thereby, S of the operation amount calculation unit 4
AC gain γ = γ _P1 = γ _P2 = γ _P3 = γ _J1 = γ _J2 = γ
_J3 (Equations (19) and (20)) is changed to the correction value γ1 (step 103). Thus, the manipulated variable calculator 4, PF
The characteristics of the C operation unit 5 are changed, and the SAC controller of the present embodiment becomes a controller suitable for the process 50 to be controlled.

According to this embodiment, after the SAC controller is adjusted to the standard process, if the actual process gain is different from that at the time of adjustment, the operator stores the actual process gain value in the process storage unit. 7, the SAC controller is automatically adjusted to execute an appropriate control operation. Thereby, the control amount y (k), which is a feature of the SAC, is converted into the reference model output ym (k).
(In the present invention, since PFC is used,
To be more precise, the control amount y (k) and the output yf of the PFC calculation unit
(The result obtained by adding (k) and (k) matches the reference model output ym (k)) can be realized. This S
The feature of AC is that it provides a valuable solution in a demand for a steel process or the like where it is desired to change a metering amount at a desired value at a desired speed.

Embodiment 2 FIG. 5 is a block diagram of a SAC controller showing another embodiment of the present invention,
The same components as those in FIG. 1 are denoted by the same reference numerals. Also in the present embodiment, the set value input unit 1, the control amount input unit 2,
The operation of the manipulated variable output unit 6 is exactly the same as that of the first embodiment, and the reference model calculation unit 3a, the manipulated variable calculation unit 4a, and the PF
The operation of the C calculation unit 5a is the same as that of the first embodiment except that the control cycle parameter is changed. Therefore, this SA
The block diagram of the control system using the C controller is the same as FIG.

In the present embodiment, the controlled object (process gain and process time constant) which has an arbitrary process dead time and has the same ratio of the process time constant and the process dead time (time constant / dead time) as the standard process described above. The same as the standard process) is set as the control target process 50.

FIG. 6 is a flowchart for explaining the operation of the controller shown in FIG. First, the cycle adjusting unit 10 reads the estimated value Lp1 of the process dead time of the control target process 50 from the process storage unit 7 (Step 201). Then, the cycle adjusting unit 10 calculates a correction value dT1 of the control cycle parameter according to the control target process 50 as in the following equation. dT1 = Lp × dT / Lp1 (24)

Subsequently, the cycle adjusting unit 10 applies the calculated correction value dT1 of the control cycle parameter to the reference model calculating unit 3.
a, to the operation amount calculation unit 4a and the PFC calculation unit 5a.
Thereby, the control cycle parameter dT of these configurations is changed to the correction value dT1 (step 202).

Here, the control cycle parameter is expressed by equation (24).
The reason for the modification will be described. FIG. 7 is a diagram for explaining the principle of adjustment for a process to be controlled at an arbitrary dead time. FIG. 7A shows the setting value sp in the controller.
Represents an ideal response waveform (control amount y0) of the standard process when a step input is applied. Also,
FIG. 7B shows an ideal response waveform (control amount y1) of the controlled process 50 when a step input is applied to the controller as the set value sp.

As shown in FIGS. 7A and 7B, the dead times Lp and Lp1 are the time from the change of the set value sp to the change of the control amount, and the time constants Tp and Tp1 are the change of the control amount. This is the time required to reach 63.2% of the set value sp. If an operation amount u ′ (k) is output from the controller to the standard process in order to obtain the ideal response shown in FIG. 7A, the SA adjusted in accordance with the standard process
In order to control the control target process 50 by using the C controller and obtain the ideal response shown in FIG. 7B, the operation amount u ′ (Lp × k / Lp1) may be output.

In order to output such manipulated variables, the control cycle parameter dT used for adjustment to the standard process is used.
Can be corrected as shown in Expression (24). Note that the actual control cycle (the cycle of one round of steps 201 to 209 in FIG. 6) remains at the initial setting (= dT) and is not changed by the cycle adjusting unit 10.

Next, the operations in steps 203 and 204 are as follows.
This is the same as steps 104 and 105 of the first embodiment. The operation of the PFC operation unit 5a is represented by Expression (16) and Expression (1).
Except that the control cycle parameter dT in 7) is changed to the correction value dT1, it is the same as the PFC calculation unit 5 of the first embodiment (step 205).

Subsequently, the operation of the reference model calculation unit 3a is as follows.
The control cycle parameter dT in the equation (18) is a correction value d.
Except for being changed to T1, it is the same as the reference model calculation unit 3 of the first embodiment (step 206). The operation of the manipulated variable calculator 4a is the same as that of the manipulated variable calculator 4 of the first embodiment, except that the control cycle parameter dT in the equation (20) is changed to the correction value dT1 (step). 207).

The operations of steps 208 and 209 are the same as steps 109 and 110 of the first embodiment. According to the present embodiment, when the actual process dead time is different from that at the time of adjustment after the SAC controller is adjusted to the standard process, the operator stores the value of the actual process dead time in the process storage unit 7. , The SAC controller is automatically adjusted to execute an appropriate control operation.

Embodiment 3 FIG. 8 is a block diagram of a SAC controller showing another embodiment of the present invention, and FIG. 9 is a block diagram of a control system using the SAC controller. The code is attached. In the present embodiment, a process having an arbitrary process time constant (the process gain and the process dead time are the same as the standard process) is set as the control target process 50.

FIG. 10 is a flowchart for explaining the operation of the controller. First, the lead lag compensator 11 reads the estimated process time constant Tp1 of the process 50 to be controlled from the process storage 7 (step 301). The operations of steps 302 and 303 are the same as steps 104 and 105 of the first embodiment.

Next, the PFC operation unit 5b performs the PFC operation in the same manner as the PFC operation unit 5 with the parameters adjusted according to the standard process (step 304). The reference model calculation unit 3b performs the reference model calculation in the same manner as the reference model calculation unit 3 with the parameters adjusted according to the standard process (step 305). Then, the manipulated variable calculator 4b calculates the manipulated variable in the same manner as the manipulated variable calculator 4 with the parameters adjusted according to the standard process (step 306).

Next, the transfer function G of the lead lag compensator 11
i can be represented by the following equation. Gi = (1 + Tp1 × s) / (1 + Tp × s) (25) The transfer function Gp1 of the controlled process 50 having a different process time constant from the standard process can be represented by the following equation. Gp1 = Kp × exp (−Lp × s) / (1 + Tp1 × s) (26)

Therefore, the transfer function G when the lead lag compensator 11 and the control target process 50 are connected in series is expressed by the following equation. G = Gi × Gp1 = {(1 + Tp1 × s) / (1 + Tp × s)} × {Kp × exp (−Lp × s) / (1 + Tp1 × s)} = Kp × exp (−Lp × s) / (1 + Tp × s) (27)

This is the same as the transfer function Gp of the standard process shown in the equation (15). If the lead lag compensation is performed in series with the control target process 50, the control target is substantially equivalent to the standard process. You can see that it can be treated as

The lead lag compensator 11 implements the lead lag compensation calculation represented by the transfer function Gi of the continuous time system of the equation (25) in the discrete time system, so that the output value ur (k) is actually expressed by the following equation. ) Is calculated. ur (k) = [Tp × ur (k−1) + u (k) × dT + Tp1 × {u (k) −u (k−1)}] / (Tp + dT) (28) where ur ( k-1) is a value one control cycle before the output value ur (k). Thus, the lead lag compensation calculation is performed (step 307).

The manipulated variable output unit 6 includes a lead lag compensation unit 11
Is output to the control target process 50 as an actual operation amount (step 308). According to this embodiment, after the SAC controller is adjusted to the standard process, if the actual process time constant is different from that at the time of adjustment, the operator stores the value of the actual process time constant in the process storage unit 7. Just memorize in the SA
C is automatically adjusted to perform an appropriate control operation.

Fourth Embodiment FIG. 11 is a block diagram of a SAC controller showing another embodiment of the present invention. The same components as those in FIGS. 1, 5, and 8 are denoted by the same reference numerals. In the present embodiment, the PFC adjustment unit 8, S
The operation of the AC adjustment unit 9 is exactly the same as that of the first embodiment, and the operations of the reference model calculation unit 3a and the cycle adjustment unit 10 are the same as those of the second embodiment.

The manipulated variable calculator 4c and the PFC calculator 5
The operation of c is the same as that of the first embodiment except that the control cycle parameter is changed. Similarly, the operation of the lead-lag compensator 11a is the same as that of the first embodiment except that the control cycle parameter is changed. It is the same as 3. Therefore, a block diagram of a control system using this SAC controller is the same as FIG.

In the present embodiment, an arbitrary process gain, an arbitrary process time constant, and an arbitrary process dead time (the ratio of process time constant / process dead time is the same as the standard process) are set as the control target processes 50. FIG. 12 is a flowchart for explaining the operation of the controller. First, the PFC adjustment unit 8 and the SAC adjustment unit 9 read the estimated value Kp1 of the process gain from the process storage unit 7, the period adjustment unit 10 reads the estimated value Lp1 of the process dead time, and the lead lag compensation unit 11
Reads out the estimated value Tp1 of the process time constant (step 401).

The operations in steps 402 and 403 are the same as steps 102 and 103 in the first embodiment. The cycle adjuster 10 calculates the correction value dT1 of the control cycle parameter in the same manner as described above. Also output to 11a. Thereby, the control cycle parameter d of the lead lag compensator 11a
T is also changed to the correction value dT1 (step 404).

It is to be noted that the actual control cycle (the cycle of one round of steps 401 to 412 in FIG. 12) is not changed as in the second embodiment. Next, step 405,
The operation of 406 is performed in steps 104 and 1 of the first embodiment.
Same as 05. The PFC calculation unit 5c performs the PFC calculation in the same manner as the PFC calculation unit 5 (step 407), but the PFC gain Kf in the equations (16) and (17) is equal to the PF
The control period parameter dT is changed to the correction value dT1 by the period adjustment unit 10 after being changed to the correction value Kf1 by the C adjustment unit 8.
Has been changed to

Subsequently, the operation of the reference model calculation unit 3a is as follows.
This is exactly the same as step 206 in the second embodiment (step 408). The operation amount calculation unit 4c includes the operation amount calculation unit 4
The operation amount is calculated in the same manner as (step 409). At this time, the SAC gain γ in equations (19) and (20) is
The AC adjustment unit 9 changes the value to the correction value γ1, and the control cycle parameter dT is changed by the cycle adjustment unit 10 to the correction value dT1.
Has been changed to

The lead lag compensator 11a performs a lead lag compensation operation in the same manner as the lead lag compensator 11 (step 410). At this time, the control cycle parameter dT in equation (28) is corrected by the cycle adjuster 10 to the correction value d.
It has been changed to T1. The operation of step 411 is the same as step 308 of the third embodiment.

Thus, the first to third embodiments can be combined. By combining these three, the operator processes the process gain, the process time constant, and the value of the process dead time for the process 50 to be controlled having an arbitrary process gain, an arbitrary process time constant, and an arbitrary process dead time. The SAC is automatically adjusted so as to execute an appropriate control operation only by storing it in the storage unit 7. That is, the number of parameters to be set is only three, and these are only parameters that can be clearly understood by an operator having no special knowledge of control.

Fourth Embodiment FIG. 13 is a block diagram of a SAC controller showing another embodiment of the present invention, and the same components as those in FIG. 11 are denoted by the same reference numerals.
This SAC controller is different from the controller of FIG. 11 in that a PID storage unit 12,
It is provided with a parameter conversion unit 13.

FIG. 14 is a flowchart for explaining the operation of the SAC controller. The PID storage unit 12 stores PID parameters set by the operator, that is, a proportional gain Kg, an integration time Ti, and a differentiation time Td. The parameter converter 13 calculates P
The proportional gain Kg, the integration time Ti, and the differentiation time Td are read from the ID storage unit 12 (step 501).

The parameter converter 13 converts the PID parameters into an estimated process gain Kp1, an estimated process time constant Tp1, and an estimated process dead time Lp1 as follows. For example, Japanese Patent Application No. 6-2
IMC (Internal Model Contr.
ol) based adjustment method and CHR (Chien, Hrones, Reswick)
According to the adjustment method, the PID parameters are set as follows.

Kg = 0.44 × Tp1 / (Kp1 × Lp1) (29) Ti = Tp1 (30) Td = 0.5 × Lp1 (31)

Therefore, the following estimation expression is obtained by performing an inverse calculation from Expressions (29) to (31). Kp1 = 0.22 × Ti / (Kg × Td) (32) Tp1 = Ti (33) Lp1 = 2 × Td (34)

Therefore, the parameter conversion unit 13 calculates the expression (3
2)-Proportional gain Kg, integration time T using equation (34)
i, the differential time Td is converted into a process gain Kp1, a process time constant Tp1, and a process dead time Lp1 (step 502). The operations of steps 503 to 513 are the same as steps 402 to 412 of the fourth embodiment.

The PID controller has a proportional gain Kg,
It can be used only by adjusting the three parameters of the integration time Ti and the differentiation time Td.
Is one of the most practical reasons. According to the present embodiment, when the PID parameters suitable for the control target are given to the PID storage unit 12, the estimated values of the process gain, the process time constant, and the process dead time are calculated from those values, and the SAC is calculated based on the estimated values. Is automatically adjusted to an appropriate value, so that the SAC can be appropriately operated with respect to an arbitrary control target process in the same adjustment manner as the PID.

[0081]

According to the present invention, as set forth in claim 1, the PFC adjustment unit automatically adjusts the PFC gain of the PFC calculation unit based on the process gain stored in the process storage unit. The SAC adjustment unit automatically adjusts the SAC gain of the manipulated variable calculation unit based on the process gain. Therefore, when the actual process gain is different from that at the time of adjustment, the actual process gain value is stored in the process storage unit. Just store the SA so that appropriate control characteristics are maintained.
The C controller can be automatically adjusted, and the control amount, which is a feature of SAC, matches the reference model output (exactly, the result of adding the control amount and the output of the PFC calculation unit matches the reference model output). Such control can be realized. As a result, the on-site operator can appropriately and easily use the SAC controller for a process to be controlled with an arbitrary process gain.

According to a second aspect of the present invention, the cycle adjusting unit adjusts the control cycle parameters of the PFC calculation unit, the reference model calculation unit, and the operation amount calculation unit based on the process dead time stored in the process storage unit. Automatic adjustment, if the actual process dead time is different from the one at the time of adjustment,
Only by storing the actual value of the process dead time in the process storage unit, the SAC is controlled so that appropriate control characteristics are maintained.
The controller can be automatically adjusted so that the control amount, which is a feature of the SAC, matches the reference model output (accurately, the result of adding the control amount and the output of the PFC calculation unit matches the reference model output). Control can be realized. As a result, the on-site operator can appropriately and easily use the SAC controller for a process to be controlled at an arbitrary process dead time.

Also, the lead-lag compensating unit performs lead-lag compensation calculation on the operation amount output from the operation amount calculating unit based on the process time constant stored in the process storage unit. When the actual process time constant is different from that at the time of adjustment, the SAC controller is automatically adjusted so that appropriate control characteristics are maintained only by storing the actual process time constant in the process storage unit. And the control amount, which is a feature of the SAC, is made to match the reference model output (accurately, the result of adding the control amount and the output of the PFC calculation unit matches the reference model output).
Such control can be realized. As a result, the on-site operator can appropriately and easily use the SAC controller for a process to be controlled having an arbitrary process time constant.

According to a fourth aspect of the present invention, the lead-lag compensating unit performs a lead-lag compensating operation on the operation amount based on the process time constant, and the PFC adjusting unit uses the PFC of the PFC calculating unit based on the process gain. The gain is automatically adjusted, the SAC adjustment unit automatically adjusts the SAC gain of the operation amount calculation unit based on the process gain, and the cycle adjustment unit calculates the PFC calculation unit and the reference model calculation based on the process dead time. Since the control cycle parameters of the control unit, the operation amount calculation unit and the lead lag compensation unit are automatically adjusted, the process gain for any process gain, any process time constant, and any process Only by storing the values of the process time constant and the process dead time in the process storage unit, the SAC control is performed so that appropriate control characteristics are maintained. Controller can be automatically adjusted. As a result, there are only three parameters to be set, and these are operators without control expertise.
The only parameters that can be clearly understood are the parameters.

Further, since the parameter converter calculates the estimated value of the gain, the time constant and the dead time of the process to be controlled from the PID parameters,
The SAC controller is automatically adjusted so that appropriate control characteristics can be maintained simply by storing PID parameters suitable for the process to be controlled with any process gain, any process time constant, and any process dead time in the PID storage unit. Control that matches the control amount, which is a feature of the SAC, to the reference model output (more precisely, the result of adding the control amount and the output of the PFC calculation unit matches the reference model output). can do. As a result, the on-site operator can execute PI for any process to be controlled.
The SAC controller can be used appropriately and easily with the same usability as the D controller.

[Brief description of the drawings]

FIG. 1 is a block diagram of a SAC controller according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a control system using the SAC controller of FIG.

FIG. 3 is a flowchart for explaining the operation of the SAC controller in FIG. 1;

FIG. 4 is a response waveform diagram of a PFC operation unit.

FIG. 5 is a block diagram of a SAC controller showing another embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of the SAC controller in FIG. 5;

FIG. 7 is a diagram for explaining the principle of adjustment of an arbitrary process dead time with respect to a control target process.

FIG. 8 is a block diagram of a SAC controller showing another embodiment of the present invention.

9 is a block diagram of a control system using the SAC controller of FIG.

FIG. 10 is a flowchart for explaining the operation of the SAC controller in FIG. 8;

FIG. 11 is a block diagram of a SAC controller showing another embodiment of the present invention.

FIG. 12 is a flowchart illustrating the operation of the SAC controller in FIG. 11;

FIG. 13 is a block diagram of a SAC controller showing another embodiment of the present invention.

FIG. 14 is a flowchart for explaining the operation of the SAC controller in FIG. 13;

FIG. 15 is a block diagram of a control system using a conventional SAC controller.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Set value input part, 2 ... Control amount input part, 3, 3a ... Reference model calculation part, 4, 4a-4c ... Operation amount calculation part,
a to 5c: PFC calculation unit, 6: manipulated variable output unit, 7: process storage unit, 8: PFC adjustment unit, 9: SAC adjustment unit, 1
0: period adjustment unit, 11, 11a: lead-lag compensation unit, 1
2 ... PID storage unit, 13 ... Parameter conversion unit.

Claims (5)

[Claims] A value obtained by adding a result of performing a parallel feedforward compensation operation to an operation amount output to a control target process and a control amount of a process is a value of a reference model in which a desired characteristic of a control system is mathematically expressed. A SFC controller that calculates the manipulated variable so as to match the output; a PFC calculator that performs a parallel feedforward compensation calculation on the manipulated variable based on a PFC gain; An operation to calculate an operation amount from the control amount, the set value, the output of the PFC operation unit and the output of the reference model operation unit, and output the operation amount to the PFC operation unit and a process to be controlled by a reference model operation unit and a SAC algorithm based on a SAC gain. An amount calculation unit, a process storage unit for storing the gain of the process to be controlled, and a process storage unit It calculates a correction value of the PFC gain from the process gain, P the PFC operation portion
A PFC adjustment unit that changes the FC gain to the correction value; and a process gain stored in a process storage unit.
A correction value of the AC gain is calculated, and the SAC of the operation amount calculation unit is calculated.
A SAC controller for changing a gain to the correction value. 2. A value obtained by adding a result of performing a parallel feedforward compensation operation to an operation amount output to a control target process and a control amount of a process is a value of a reference model in which desired characteristics of a control system are mathematically expressed. A SFC controller that calculates the manipulated variable so as to match the output; a PFC computing unit that performs a parallel feedforward compensation computation on the manipulated variable based on a PFC gain and a control cycle parameter; An operation amount is calculated from the control amount, the set value, the output of the PFC operation unit, and the output of the reference model operation unit by a reference model operation unit that performs a reference model operation based on a period parameter and a SAC algorithm based on a SAC gain and a control period parameter. And PF
A C operation unit and an operation amount calculation unit for outputting to the control target process; a process storage unit for storing a dead time of the control target process; and a correction of the control cycle parameter based on the process dead time stored in the process storage unit. A SAC controller comprising: a period adjustment unit that calculates a value and changes a control period parameter of a PFC operation unit, a reference model operation unit, and an operation amount calculation unit to the corrected value. 3. A value obtained by adding a result of performing a parallel feedforward compensation operation to a manipulated variable output to a control target process and a control amount of a process is a value of a reference model in which desired characteristics of a control system are mathematically expressed. A SFC controller that calculates the manipulated variable so as to match the output; a PFC calculator that performs a parallel feedforward compensation calculation on the manipulated variable based on a PFC gain; A reference model calculation unit to be performed; and a control amount calculation unit that calculates a control amount from the control amount, the set value, the output of the PFC calculation unit and the output of the reference model calculation unit by a SAC algorithm based on a SAC gain, and outputs the control amount to the PFC calculation unit. A process storage unit for storing the time constant of the process to be controlled, and a process record for the operation amount output from the operation amount calculation unit. Performs lag compensation calculation based on the stored process time constant in the section, SAC controller; and a lead-lag compensation unit for outputting the operation result as the manipulated variable to the controlled process. 4. A value obtained by adding a result of performing a parallel feedforward compensation operation to an operation amount output to a control target process and a control amount of a process is a value of a reference model in which desired characteristics of a control system are mathematically expressed. A SFC controller that calculates the manipulated variable so as to match the output; a PFC computing unit that performs a parallel feedforward compensation computation on the manipulated variable based on a PFC gain and a control cycle parameter; An operation amount is calculated from the control amount, the set value, the output of the PFC operation unit, and the output of the reference model operation unit by a reference model operation unit that performs a reference model operation based on a period parameter and a SAC algorithm based on a SAC gain and a control period parameter. And PF
An operation amount calculation unit to be output to the C operation unit; a process storage unit for storing a gain, a time constant, and a dead time of a process to be controlled; and a process storage unit for the operation amount output from the operation amount calculation unit A lead-lag compensation operation is performed based on the calculated process time constant, and a lead-lag compensation unit that outputs the operation result as an operation amount to the process to be controlled is provided.
A PFC adjustment unit that calculates a correction value of the FC gain and changes the PFC gain of the PFC calculation unit to the correction value;
Calculating a correction value of the AC gain, changing the SAC gain of the operation amount calculation unit to the correction value, and calculating a correction value of the control cycle parameter from the process dead time stored in the process storage unit. , A PFC operation unit, a reference model operation unit, an operation amount calculation unit, and a cycle adjustment unit that changes a control cycle parameter of the lead lag compensation unit to the corrected value. 5. A value obtained by adding a result of performing a parallel feedforward compensation operation to an operation amount output to a process to be controlled and a control amount of a process is a value of a reference model in which desired characteristics of a control system are mathematically expressed. A SFC controller that calculates the manipulated variable so as to match the output; a PFC computing unit that performs a parallel feedforward compensation computation on the manipulated variable based on a PFC gain and a control cycle parameter; An operation amount is calculated from the control amount, the set value, the output of the PFC operation unit, and the output of the reference model operation unit by a reference model operation unit that performs a reference model operation based on a period parameter and a SAC algorithm based on a SAC gain and a control period parameter. And PF
A manipulated variable calculation unit to be output to the C calculation unit; a PID storage unit for storing a PID parameter suitable for the process to be controlled; a gain of the process to be controlled based on the PID parameter;
A parameter conversion unit for calculating an estimated value of the time constant and the dead time; and a lead-lag compensation calculation for the operation amount output from the operation amount calculation unit based on the process time constant calculated by the parameter conversion unit. A lead lag compensating unit that outputs the PFC gain as an operation amount to the process to be controlled, and a correction value of the PFC gain calculated from the process gain calculated by the parameter conversion unit.
A PFC adjustment unit that changes the C gain to this correction value; and a correction value of the SAC gain calculated from the process gain calculated by the parameter conversion unit.
A SAC adjustment unit for changing the C gain to the correction value; a correction value for the control cycle parameter calculated from the process dead time calculated by the parameter conversion unit; a PFC calculation unit, a reference model calculation unit, and an operation amount calculation unit And a period adjusting unit for changing a control period parameter of the lead lag compensating unit to the corrected value.