JPH07122227B2 - Paper machine control device and control method thereof - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an apparatus for controlling a paper machine for producing paper, and more particularly to an improvement suitable for producing paper of uniform quality.

<Prior Art> A control device for a paper machine is known, for example, in Japanese Patent Laid-Open No. 63-75197 proposed by the present applicant. FIG. 14 is a configuration perspective view of the entire paper machine. In the figure, the head box 5
The raw material discharged from the wire is squeezed by passing through the wire part 8, compressed by the press part 9 to a predetermined paper thickness, dried by passing through the dry part 15, and passed through the calendar 11. The surface of the paper is made glossy by and is wound on the reel 12. The head box 5 is provided with slice lips 6 for discharging the raw material liquid and several tens of slice bolts 7 for adjusting the opening of the slice lips 6 at regular intervals in the width direction of the paper. The white water silo 3 receives the white water produced by squeezing water from the wire part 3, and is returned to the head box 5 by the pump 4. At the inlet of the pump 4, the seed valve 2 injects the raw material (seed) in the seed box 1.

The sensor 14 for measuring the basis weight and the moisture content of the paper is one that reciprocates along the frame 13 installed between the calendar 11 and the reel 12 to measure in the paper width direction. The one disclosed in USP 4.315,150; 4,620,146 is used. The data in the paper width direction is called a profile. The controller 16 inputs the basis weight profile measured by the sensor 14 and operates the slice bolt 7 so as to obtain a target basis weight, thereby controlling the opening degree of the slice lip 6. For the moisture content, enter the moisture content profile and control the steam amount of the dry part 15 so that the target moisture content is achieved, and the deviation from the target value of the grammage average value is the opening of the seed valve 2. Is controlled.

FIG. 15 is a functional block diagram of the paper machine controller. In the figure, a profile calculation unit 32 calculates a deviation between a measurement profile signal measured by the sensor 14 and a predetermined target profile, and actually operates the measurement profile signal with reference to the position correspondence unit 34. Corresponds to each slice, which allows control deviation for each slice (k). Is required. For the measurement profile, for example, the total number of measurement points may be 360 points in the width direction, and the adjacent 6 points may be averaged for smoothing. For the target profile, for example, the basis weight at the center is slightly increased, while both ends are slightly decreased so that the reel 12 can be stably wound. Position corresponding part
Reference numeral 34 describes the correspondence between the measurement points of the measurement profile signal and the slices, which is determined in advance by theoretical formulas or experiments. The slice operation amount calculation unit 38 determines the slice to be operated in this control cycle and the change amount of the operation amount. Is a core part of the controller 15. The output control unit 60 is the change operation amount for each slice obtained by the slice operation amount calculation unit 38. The previous operation amount To the current operation amount Is set as a natural multiple of the scanning period of the sensor, or is set based on the time constant of the paper machine and the calculation capability of the controller. For example, if the scanning cycle of the sensor 14 is 30 seconds, the control cycle of the output control unit 60 is set to every 2 minutes.
The slice operation amount calculation unit 38 is used in many paper mills that are manually operated by a skilled operator.

FIG. 16 is a block diagram showing the construction of the paper machine control system with attention paid to the controller 16, and describes the control state in detail. Here, in order to simplify the explanation, it is shown in a state corresponding to slices. In the controller 16, the target value (setting value, here The basic weight profile y fed back
The manipulated variable is calculated from the deviation e (K) from (K). The slice bolt 7 is adjusted by this operation amount, and the basis weight profile that changes as a result is fed back. Then, the deviation e (K) is controlled so as to approach 0.

The operation amount in such a control system is a slice lip opening pattern {u ₁ , ..., U _N }, and the control amount is a basis weight profile {y ₁ , ..., Y _N }. The plant can be approximated by the first-order lag and the interference in the width direction, which is expressed as follows in the s-domain in the Laplace transform.

Y (S) = {k / (1 + T _S } AU (S) (1) where Y (S) is a vector Laplace transformation of Is the transpose of the matrix [y1 (t), ..., yN (t)] ([y
₁ (t), ..., y _N (t)] T). U
(S) is a vector Laplace transformation of Is a transposed matrix of [u ₁ (t), ..., u _N (t)], k is a gain, T is a time constant, and A is an interference matrix (N × N), which satisfies the following relationship.

And t is time.

The conventional control law is a combination of calculation considering interference and PI (proportional / integral) control considering first-order lag. This is expressed as follows in discrete time and speed form.

Where k is discrete time, Is the discrete-time slice lip opening vector, Is the difference, Is the discrete-time control deviation vector, e _i (k) is the control deviation, Are the differences and satisfy the following relationships.

Then, K _P is a proportional gain, K _I is an integral gain, and M is an N × N matrix considering interference.

Next, the operation will be described. Deviation between target value and control amount obtained at addition point 21 (control deviation) Then, the calculator 22 performs a calculation in consideration of interference. This result is expressed by the following equation.

In this case, the following expression holds between e '(k) and e (k).

The controller 25 has Is entered. Difference Is the output of calculator 22 And previous output value of computing unit via buffer 23 Is obtained from the addition point 24 and is expressed by the following equation.

Then, the controller 25 performs PI calculation as in the following equation.

This operation can also be represented by a scalar operation for each element of the vector as follows.

Δu _i (k) = K _P Δe ⁻ _i (k) + K _I e ⁻ _i (k) (5) (i = 1 to N) The adder 26 holds the previous slice lip opening vector held by itself. Output from the controller 25 Is added to this slice lip opening vector Output as. This slice lip opening vector Is the manipulated variable via the zero-order hold circuit 27 As plant 28.

The output (basis weight profile) y (t) of the plant 28 is taken out through a sampler 29 that samples every k hours and fed back to the addition point 21.

<Problems to be Solved by the Invention> By the way, the plant is ideally expressed by the equation (1), but since it actually includes complicated nonlinear characteristics (2)
There is a problem that the linear control like the formula is insufficient.

FIG. 17 is an explanatory diagram of the sawtooth wave between slices, (A) showing before operation and (B) showing after operation. In the figure, the horizontal line represents the width direction of the paper, the curved line represents the basis weight profile at that position, and the vertical line (+) represents the position of the measurement end where the influence of the slice is most prominent (called position correspondence). The arrow (↓) represents the operation of the corresponding slice. In order to eliminate the sawtooth wave between slices, operate the slices on both sides with two slices in between.
(Fig. 17 A). However, in some cases, the valley of the basis weight was generated at the position of the operated slice, and the sawtooth wave was rather increased (FIG. 17B).

Due to the complexity of the process, the basis weight profile response to slice manipulations often does not appear to be ideal.
In particular, when manipulating many slices at a time, the basis weight profile may be disturbed, requiring the assistance of a skilled operator.

When the process is extremely disturbed, such as when a major brand change or the start of the operation of the paper machine, it takes a very long time to converge the profile to the quality recognized as a product, resulting in a huge amount of waste paper. .

The slice may have a permanent set due to excessive bending, and once the permanent set is made, the lip opening cannot be adjusted even if the slice bolt is operated. Therefore, it is necessary to limit the difference in opening between adjacent slice bolts to regulate the operation amount. However, according to the conventional device, even if the basis weight is uniform, the lip opening pattern of the slice may be disturbed, and the adjacent lip opening limit may be exceeded. If within a certain range,
It is considered that the influence of the stress distribution of the raw material output and the shape of the slice lip is guaranteed, but excessive disturbance is a problem in protecting the slice.

A first object of the present invention to solve the above-mentioned problems is to adopt a fuzzy control means incorporating a manual operation method of a skilled operator to surely flatten the basis weight profile of a sawtooth wave. To provide the equipment. Second of the present invention
It is an object of the invention to provide an apparatus capable of converging the profile to the product level in a short time even when the process is largely disturbed.

A third object of the present invention is to provide a device capable of stably controlling the basis weight profile while keeping the opening of the slice lip smooth.

<Means for Solving the Problems> A first invention for achieving the above first and second objects is to slice a plurality of slices (6, 7) arranged in the width direction of the paper for controlling the supply amount of the paper raw material. ) And a sensor (14) for measuring the quality of the produced paper in the width direction of the paper, with respect to a paper machine having a value detected by this sensor in a direction that matches a predetermined target profile. The paper machine control device for operating the slice has the following configuration.

That is, the measurement point of the sensor, the position corresponding section (34) to determine which of the slices the position corresponds to, the deviation between the detected basis weight profile and the target profile, according to the correspondence relationship of the position corresponding section, The profile calculation unit (32) calculates the slice and the difference profile calculation unit (37) calculates the difference between the deviation profiles obtained in the previous and current control cycles.

In addition, as the slice calculation unit (70), the deviation profile,
Evaluation function unit having a membership function of a predetermined number of fuzzy functions related to the difference profile and the change operation amount (74)
And a forward operation rule that operates in a direction to match the deviation profile to the target value, a reverse operation rule that operates the deviation profile that substantially matches the target value but considers the influence of the difference profile, and a deviation profile that sets the target value. And the difference profile value is not small, an operation rule section (76) having a waiting rule for forgoing this operation, a deviation profile output by the profile calculation section, and a difference profile output by the difference profile calculation section. And a fuzzy inference unit (72) for determining the current operation rule by referring to the operation rule unit and for determining the current change operation amount according to the evaluation function unit.

The fuzzy inference unit is provided with an output control unit (60) that changes the operation amount according to the changed operation amount and sends the control amount to the slice.

A second invention for achieving the second and third objects is the following configuration in the above-described paper machine control device.

The position corresponding to the measurement point of the sensor, which determines which position of the slice corresponds (34), and the deviation between the detected basis weight profile and the target profile, according to the corresponding relationship of the position corresponding part, the slice And a slice operation amount calculation unit (38) that calculates the amount of change in the operation amount for each slice in order to match the measurement profile with the target profile from the calculation result of this profile calculation unit, A gap calculator (81) that obtains the gap of the slice before the current manipulated variable is output from the lip opening of the adjacent slice and the lip opening of the slice. A correction amount calculation unit (82) for obtaining a correction amount for the gap by a decreasing function, the correction amount obtained by the correction amount calculation unit and the An operation amount correction unit (80) having an addition / correction unit (83) for adding the operation amount change amount obtained by the rice operation amount calculation unit and outputting the addition result to the output control unit as the current operation amount change amount; The output control unit (60) sends the operation amount smoothed by the operation amount correction unit to each slice as the current operation amount.

<Operation> Each component of the present invention has the following action. The profile calculation unit is the deviation profile between the grammage profile this time and the target value. Ask for. The difference profile calculator calculates the difference profile between the previous control cycle and the current control cycle. Ask for. The fuzzy inference part refers to the evaluation function part and the operation rule part from these values and changes this time. Is calculated. The output control unit uses a new operation amount based on the result calculated by the fuzzy inference unit. Is output to the slice.

Preferably, a manipulated variable correcting unit is provided to control the manipulated variable from the output control unit. If the smoothing process is performed before the output of, the stable control can be performed without the risk of damaging the slice.

<Examples> The present invention will be described below with reference to the drawings.

<< Embodiment 1 >> FIG. 1 is a configuration block diagram showing an embodiment of the present invention. Incidentally, in FIG. 1, the same reference numerals are given to those having the same functions as those in FIG. In the figure, the difference profile calculation unit 37 indicates the deviation profile in the previous and present control cycles calculated by the profile calculation unit 32. The difference profile Output as. The slice operation unit 70 is an operation that stores a fuzzy inference unit 72 that executes inference by a method known in fuzzy control theory such as Mamdani's method, an evaluation function unit 74 that represents a fuzzy variable and a membership function, and a rule table. It has a rule part 76. The evaluation function unit 74 uses the deviation profile. Function part 742 for, differential profile Function part 744 and change operation amount for It has a function part 746 for. The operation rule section 76 is
The forward operation rule unit 762 that defines the case of operating the slice in the direction of canceling the deviation profile, and the deviation of the deviation profile itself is small, but when the existence of the difference profile predicts the excess of the deviation profile in the future, this The reverse operation rule part 764 that defines the case of operating the slice in the direction of canceling the expected excess line, and the waiting rule part 766 and the difference profile that delay the slice operation until the deviation profile stabilizes because the value of the difference profile is large. A divergence prevention rule unit 768 that operates the slice in a direction to prevent divergence when the deviation profile may diverge due to a large value of The output control unit 60 is a change operation amount output from the fuzzy inference unit 72. Is added to the previous operation amount to adjust the slice lip opening. To the slice bolt 7.

FIG. 2 is an explanatory diagram of the evaluation function unit 74. (A) is a deviation profile function unit 742, (B) is a difference profile function unit 744,
(C) represents the change manipulated variable function unit 746. In the figure, there are 7 types of fuzzy variables, NB (negative big)
Is negative and large, NM (negative medium) is negative and medium, and NS (neg
ative small) is negative and small, ZO (zero) is zero, PB (posit
ive big) is positive and large, PM (positive medium) is positive and medium, and PS (positive small) is positive and small.

In the deviation profile function unit 742, the fuzzy variable is 7
There are types, and the membership function is a triangle. Fit of 0-1 the vertical axis, the horizontal axis -e _imax to e range of _imax deviation profile ei (scalar) are marked. The fuzzy variables NB to PB are arranged at equal intervals in the illustrated order, and each fuzzy variable partially overlaps the adjacent fuzzy variables. In the difference profile function unit 744, there are five types of fuzzy variables except NM and PM, and the membership function includes a left-right asymmetric triangle. The vertical axis shows the fitness of 0 to 1, and the horizontal axis shows the difference profile Δei (scalar) in the range of −Δe _{imax to} Δe _imax . Each fuzzy variable
NB to PB are arranged in the order shown in the figure, and the interval P _B2 between PS and PB (or NS and NB) is wider and unequal than the interval P _B1 between ZO and PS (NS). In the change manipulated variable function unit 746, there are the above seven types of fuzzy variables, and the membership function is triangular. The vertical axis shows the fitness of 0 to 1, and the horizontal axis shows the change operation amount Δui (scalar) in the range of −Δu _{imax to} Δu _imax . The fuzzy variables NB to PB are arranged in the order shown in the figure, and is the interval P _C1 , PS between ZO and PS (NS).
And PM (or NS and NM), the interval P _C2 and PM and PB (or NM and NB), the interval P _C3 are unequal intervals that satisfy the following relationship.

P _C1 <P _C2 <P _C3 (6) Because the deviation profile e is large, the large deviation profile e causes small slice operation (time constant + dead time) and the deviation profile e is small. This is because the paper machine has a dynamic characteristic that (time constant + dead time) increases when the slice is operated small. Change operation amount Is 0.0 mm for ZO, 0.1 mm for PS (NS) and 0 for PM (NM).
It is 4mm and 1.0mm for PB (NB). The parameters of the membership function of each fuzzy variable are adjusted according to the plant to be controlled. For example, e imax, Δe
It is not necessary to adjust the values of imax and Δu _imax and usually to the shape of the membership function.

FIG. 3 is a diagram for explaining the concept of the operation rule unit 76, where the vertical axis is the deviation profile e and the horizontal axis is the difference profile Δe. The forward operation rule portion 762 is an area where the difference profile Δe is small and exists along the vertical axis. The reverse operation rule portion 764 is an area where the deviation profile e is small and exists along the horizontal axis. The central portion 765 is near the origin where the vertical axis and the horizontal axis intersect, and corresponds to the area ZO where the forward operation rule section 762 and the reverse operation rule section 764 cancel each other's influence and the change operation amount becomes zero. . The waiting rule unit 766 is an area in which the deviation profile e and the difference profile Δe have values that are not small, and is an area that waits for a slice operation until the control state stabilizes. The waiting rule unit 766 enhances robustness against fluctuations in plant dynamic characteristics. The divergence prevention rule unit 768 may be provided in a part of the waiting rule unit 766 to prevent the control state from diverging.

Curves OP1 to OP3 are phase diagrams in the control state. When a slice is manipulated with a large deviation profile e, the measurement profile changes, so a semicircular curve as shown in the figure is drawn.
Generally, in the middle of changing, it moves from the forward operation rule unit 762 to the waiting rule unit 766, and enters the forward operation rule unit 762 again according to the process (curve OP1), the reverse operation rule unit 76.
There is also one that moves to the central part 765 through 4 (curve OP2) or reaches the forward operation rule part 762 through the reverse operation rule part 764 (curve OP3).

FIG. 4 is a diagram showing the details of the operation rule section 76 and corresponds to FIG. The forward operation rule unit 762 is assigned PS to PB (NS to NB) according to the value of the deviation profile e. Similarly, PS, PB, NS and NB are assigned to the reverse operation rule section 764 according to the value of the difference profile Δe. ZO is assigned to the central portion 765. The waiting rule section 766 has no assignment in principle, and therefore represents waiting. Four divergence prevention rule parts 768 are provided in the area of the waiting rule part 766. When the coordinates of the phase plane are represented by (e, Δe), these are NB for (NB, NB), PB for (PB, PB), and P for (NS, PB).
S and (PS, NB) are assigned as NS. The former two are areas in which the absolute values of the deviation profile and the difference profile are large, and the signs are the same. In the latter two cases, the absolute value of the deviation profile is large, and the sign of the difference profile is opposite to the sign of the deviation profile and is a small area of the absolute value.

FIG. 5 is an explanatory diagram of the operating state of the paper machine according to this embodiment.
(A) is the dispersion state of the measurement profile, (B) is the trend of the manipulated variable, and the horizontal axis is time. here,
It shows from the start of paper passing to 4 hours later. It is understood that the manipulated variable approaches a certain value with the passage of time. FIG. 6 is an explanatory diagram of the conventional PI control, which is used for comparison with this embodiment. In the present embodiment, the deviation profile e of the same magnitude due to some disturbance is largely operated earlier than in the PI control and is calmed down successfully. Further, when the deviation profile e is small, it is controlled without causing hunting.

The fuzzy operation here is the deviation profile And diff profile Change operation amount from Since it is a non-linear mapping to, the control of a system having non-linearity such as a paper machine has an effect that adjustment according to the characteristics of the process can be easily performed.

Example 2 Next, an example of the present invention for smoothing the slice operation amount will be described. FIG. 7 is a constitutional block diagram for explaining the second embodiment of the present invention. Incidentally, in FIG.
The components having the same functions as those in the figure are designated by the same reference numerals and the description thereof will be omitted. In the figure, the slice operation amount calculation unit 38 indicates the amount of change in the operation amount for each slice for matching the measurement profile with the target profile from the calculation result of the profile calculation unit 32. Is calculated. The operation amount correction unit 80 includes a gap calculation unit 81, a correction amount calculation unit 82, and an addition / correction unit 83,
Change operation amount obtained by slice operation amount calculation unit 38 Correction amount considering keeping the slice lip opening smooth Is to add. The correction amount s (k) is The calculation in the manipulated variable correcting unit 80 is represented in the form of the following.

It can also be written element by element like this:

Δu _i (k) + s _i (k) → Δu _i (k) However, i = 1 to N Next, each element of the manipulated variable correcting unit 80 will be described in detail. FIG. 8 is an explanatory diagram of the calculation of the gap calculator 81.
The gap calculator 81 determines the gap u _i-GAP of the central slice before the current manipulated variable output from the lip opening of the adjacent slices and the lip opening of the slices existing between them.
Calculate (k). The calculation in this case is given by the following equation.

u _i-GAP (k) = u _i (k)-{ui-1 (k) + ui + 1
(K)} / 2 (8) In this way, Si (k) is the lip opening of adjacent slices {... u _i-1 (k), u _i (k), u _{i + 1} (k), ... } It is decided from. This lip opening is equal to the opening performed in the previous control cycle and the change operation amount calculated by the slice operation amount calculation unit 38 in this control cycle. It is recommended to use the value obtained by adding.

FIG. 9 is an explanatory diagram showing an example of the function of the correction amount calculation unit 82. The correction amount calculation unit 82 is a function in which the correction amount s _i (k) has u _i-GAP (k) calculated by the gap calculation unit 81 as a parameter, and is represented by the following equation.

s _i (k) = − (u _i-GAP (k)) (9) This function is a monotone non-decreasing function as shown in the figure.
The slope of the straight line and the value of point a in FIG. 9 are appropriately determined according to the current situation. Preferably, if the absolute value of the gap is a certain value or less, a dead zone for setting the correction amount s _i (k) to zero may be provided.

The addition / correction unit 83 executes the above-mentioned expression (7) in principle. Exceptionally, change operation amount The value of the correction amount si (k) has the opposite sign, and the absolute value of the correction amount s _i (k) changes Considering a case where the slice operation amount is larger than that, it is possible that the original operation calculated by the slice operation amount calculation unit 38 is not performed at all. In order to avoid this, the correction circuit uses the following algorithm for correction.

(A) When 0 <α · Δu _i (k) <− s _i (k) or −s _i (k) <α · Δu _i (k) <0, the following equation is executed.

(1-α) · Δu _i (k) → Δu _i (k) (10) However, α is an appropriate value within the range of 0 <α <1.

In the other cases of (b), the above equation (7) is performed.

Δu _i (k) + s _i (k) → Δu _i (k) (7) By such correction in the operation amount correction unit 80, the slice lip opening pattern output from the slice operation amount calculation unit 38 It can be smoothed according to the slice lip opening and input to the output control unit 60. Becomes a smooth curve, and the basis weight profile can be controlled while keeping the slice lip opening of the plant smooth.

<< Embodiment 3 >> FIG. 10 is a configuration block diagram for explaining the third embodiment of the present invention. In comparison with FIG. 7, only the manipulated variable correcting unit 80 is changed. In the figure, the operation amount correction unit 80 is a rough operation amount calculation unit 8
4, a spline function unit 85, a model matching unit 86, and a slice corresponding unit 87. Rough operation amount calculator
84 is the change operation amount obtained by the slice operation amount calculation unit 38 And the previous operation amount output to the slice from the output control unit 60 Is added, and this time the operation amount Calculate the rough value of. This value is the slice lip opening pattern {u ₁ , u ₂ , ..., U _N } before smoothing.

Figure 11 shows the amount of slice operation It is explanatory drawing of and the coordinate normalized. The spline function unit 85 considers the positions of the start and end of the slice and determines the interval [0,
1] has the normalized coordinates corresponding to each slice normalized to the coordinates. Next, in the section [0,1], the mth floor (m-1
, Ξ _1-m , ..., ξ _{n + m} satisfy the following relation: Normalized B-spline function B _i (X) (i = 1 to n +
m) is prepared.

0 = ξ _1-m ＝ ・ ・ ・ ＝ ξ ₀ <ξ ₁ … ＜ ξ _n <ξ _{n + 1} <ξ _{n + 1} ＝
… ＝ ξ _{n + m} = 1 (11) [However, ξ _im <ξ _i (i = 1,2, ..., n + m) is satisfied] That is, B _i (X) = (ξ _i −ξ _im ) M _mi (X) However, the recurrence formula of M _mi is as follows.

FIG. 12 is a diagram showing an example of the B-spline function part.
Here, the fourth floor (third order), node 10 (ξ ₀ = ξ ₁ = ξ ₂ =
ξ ₃ = 0, ξ ₄ = 1/3, ξ ₅ = 2/3, ξ ₆ = ξ ₇ = ξ ₈ = ξ ₉
6 B-spline functions of = 1) are prepared.

The model matching unit 86 uses the rough operation amount calculated by the rough operation amount calculation unit 84. Is approximated by a linear combination of B-spline functions of the spline function unit 85. The linear combination is given by

Approximation is performed as a least squares method with parameters C _i (i = 1, ..., n +
Solve m). That is, Minimize.

Partial differentiation of the above equation (14) with the parameter C _i creates the following normal equation.

However, Therefore, the least squares solution is expressed by the following equation.

Note that the Cholesky method can be effectively used for this calculation, considering that the coefficient matrix A is actually a band matrix.

Subsequently, the slice corresponding unit 87 uses the coefficient C _i obtained by the above equation (16) to obtain the smoothed slice lip opening pattern {u ₁ ′, ..., uN ′} from the above equation (13), It is expressed as follows.

u _i ′ = S _i (xi) = Σc _i B _i (x _i ) (17) The basic formula for expanding the slice lip opening pattern defined by the spline function unit 85 is limited to the linear combination of B-spline functions. Alternatively, other spline functions or linear combinations of various functions may be used.

Further, in the above, the minimization of the error sum of squares [Equation (15)] is applied for the approximation of the model matching unit 86, but in addition, the error S (x _k ) −u _k (k = 1, ... , N) may be applied to minimize the evaluation function that comprehensively evaluates.

Further, in the case of correcting to {u ₁ ′, ..., u _N ′} obtained by smoothing from the current slice lip opening pattern, after smoothing processing is continued several times instead of one smoothing processing. You may output to an output control part. Further, the smoothing may be performed not for all the slices but only for a part thereof.

FIG. 13 is a flow chart for explaining another embodiment of the second and third embodiments. First, the slice lip opening pattern {u ₁ ,…,
evaluate u _N }. When it is determined in this evaluation step that the lip opening pattern is disturbed, a smoothed lip opening pattern is calculated. The criterion for determining whether or not this disorder is, for example, the dead zone provided in FIG.
It is preferable to provide them separately from the slice operation amount calculation unit 38 and the operation amount correction unit 80. Then, the slice lip opening is operated so as to match the smoothed pattern {u ₁ ′, ..., U _N ′}.

When it is determined by the evaluation step that the lip opening degree pattern of the slice is not disturbed, the slice is operated so as to match the pattern {u ₁ , ..., U _N }.

<Effects of the Invention> As described above, the present invention has the following effects.

(1) According to the first embodiment, the fuzzy control is used for the basis weight profile control, and the deviation profile such as the forward operation, the reverse operation, and the operation wait is used. And the difference profile Δ Detailed operation amount according to the state of Can be set, and even if the characteristics of the paper machine include non-linearity and uncertainty, a control system that takes this into account can be configured to improve responsiveness and robust stability and stabilize quality. .

(2) According to the second and third embodiments, the manipulated variable correcting unit
The operation amount output from the output control unit 60 by providing 80 Is smoothed and the slice is manipulated, so
Excessive variation in the lip opening of the slice is prevented, the reliability of the slice operation is improved, and the basis weight profile control is also stable.

[Brief description of drawings]

FIG. 1 is a structural block diagram showing a first embodiment of the present invention, FIG. 2 is an explanatory diagram of an evaluation function unit 74, FIGS. 3 and 4 are explanatory diagrams of an operation rule unit 76, FIG. 5 and FIG. FIG. 6 is a trend diagram for explaining the operating state of the paper machine. FIG. 7 is a structural block diagram showing a second embodiment of the present invention, FIG. 8 is an explanatory diagram of the gap calculation unit 81, FIG. 9 is a diagram showing an example of the correction amount calculation unit 82, and FIG. 10 is the present invention. 11 is an explanatory view of the spline function unit 85, and FIG. 13 is a flow chart for explaining another embodiment. FIG. 14 is a perspective view of the configuration of the entire paper machine, FIG. 15 is a configuration block diagram of the paper machine control device, FIG. 16 is a configuration block diagram focusing on the control function, and FIG. 17 is an explanatory diagram of the sawtooth wave between slices. Is. 6 ... Slice bolt, 7 ... Slice lip, 14 ...
Sensor, 32 ... Profile calculation unit, 34 ... Position corresponding unit,
37 …… Differential profile calculation unit, 38 …… Slice operation amount calculation unit, 60 …… Output control unit, 72 …… Fuzzy reasoning unit, 74…
… Evaluation function part, 76 …… Operation rule part, 80 …… Operation amount correction part.

Claims (12)

[Claims] 1. A paper machine having a plurality of slices arranged in the width direction of the paper for controlling the supply amount of the paper raw material and a sensor for measuring the quality of the manufactured paper in the width direction of the paper. Then, in the paper machine control device that operates the slice in the direction in which the value detected by this sensor matches a predetermined target profile, the measurement point of the sensor determines which position of the slice the position corresponds to. The corresponding part, the deviation between the detected basis weight profile and the target profile,
A profile calculation unit that calculates the slice according to the correspondence relationship of the position corresponding unit, a difference profile calculation unit that calculates the difference between the deviation profiles obtained in the previous and current control cycles by the profile calculation unit, the deviation profile, the difference An evaluation function part having a membership function of a predetermined number of fuzzy functions related to the profile and the amount of change operation, a forward operation rule for operating the deviation profile to match the target value, and the deviation profile substantially matches the target value. An inverse operation rule that operates in consideration of the influence of the difference profile, and an operation rule section having a waiting rule for which the deviation operation deviates from the target value and the difference profile value is not small, and the profile calculation Difference profile output from the differential profile calculation unit and the difference profile output from the difference profile calculation unit. A fuzzy inference unit that determines the current operation rule by referring to the relevant operation rule unit and determines the current operation amount according to the evaluation function unit, and the operation amount by the change operation amount output from this fuzzy inference unit. An output control unit that changes the control amount and sends the control amount to the slice, the paper machine control device. 2. The evaluation function section arranges the fuzzy variables at equal intervals for the deviation profile, and regards the difference profile and the amount of change operation as the fuzzy variables having a larger distance from zero are adjacent to the fuzzy variables on the zero side. The paper machine control device according to claim 1, wherein the interval between the two is increased. 3. The fuzzy variables are NB (negative and large), NS
(Negative and small), ZO (zero), PS (positive and small) and PB (positive and large)
3. The paper machine control device according to claim 2, wherein the paper machine control device comprises at least five. 4. The paper machine controller according to claim 1, wherein the operation rule section has zero as a change operation amount when the values of the deviation profile and the difference profile are both small. 5. The paper machine controller according to claim 1, wherein the forward operation rule of the operation rule section is an operation rule having a large change operation amount when the deviation profile value is large. 6. The paper machine control device according to claim 1, wherein the reverse operation rule of the operation rule section is an operation rule having a large change operation amount when the difference profile value is large. 7. The divergence prevention which prevents the divergence by a certain rule and a waiting rule for which the current operation is put off in an area where the deviation profile deviates from the target value and the value of the difference profile is not small. The paper machine control device according to claim 1, further comprising a rule section. 8. The paper machine control device according to claim 7, wherein the divergence prevention rule is provided in a region where the absolute values of the deviation profile and the difference profile are large. 9. The papermaking machine according to claim 7, wherein the divergence prevention rule section is provided in a region where the absolute value of the deviation profile is large and the sign of the difference profile is opposite to the sign of the deviation profile and has a small absolute value. Machine control device. 10. A paper machine having a plurality of slices arranged in the width direction of the paper for controlling the supply amount of the paper raw material, and a sensor for measuring the quality of the manufactured paper in the width direction of the paper. Then, in the paper machine control method of operating the slice in a direction in which the value detected by this sensor matches a predetermined target profile, the measurement point of the sensor determines a position corresponding to which of the slices. Corresponding step, the deviation between the detected basis weight profile and the target profile,
A profile calculation step for calculating the slice according to the correspondence relationship of the position corresponding step, a difference profile calculation step for calculating the difference between the deviation profiles obtained in the previous and present control cycles by the profile calculation step, the deviation profile, the difference An evaluation function process having a predetermined number of fuzzy function membership functions related to the profile and the amount of change operation, a forward operation rule for operating the deviation profile in a direction to match the target value, and the deviation profile substantially matches the target value. An inverse operation rule which operates in consideration of the influence of the difference profile, and an operation rule step having a waiting rule for which the deviation operation deviates from the target value and the difference profile value is not small, Deviation profile output by the process and the difference profile calculation process Input the differential profile output by, and determine the operation rule of this time by referring to the operation rule process, and the fuzzy inference process that determines the current change operation amount according to the evaluation function process, and the change operation amount output by this fuzzy inference process. An output control step of changing the manipulated variable according to to send the controlled variable to the slice. 11. Slices (6, 7) arranged in the width direction of the paper for controlling the supply amount of the paper raw material, and a sensor (14) for measuring the quality of the manufactured paper in the width direction of the paper. ) With respect to the paper machine having, in the paper machine control device for operating the slice in a direction in which the value detected by this sensor matches a predetermined target profile, the measurement point of the sensor is one of the slices. A position corresponding part (34) for determining whether or not the position corresponds to, and a deviation between the detected basis weight profile and the target profile,
A profile calculator (32) that calculates the slice according to the correspondence relation of the position corresponding part, and a change amount of the operation amount for each slice for matching the measurement profile with the target profile from the calculation result of the profile calculator. Slice operation amount calculator (38)
And, from the lip opening of the adjacent slice and the lip opening of the slice, the gap calculation unit (81) for obtaining the gap of the slice before the current manipulated variable output, the gap obtained by this gap calculation unit as a variable, A correction amount calculation unit (8 that calculates the correction amount for the gap using a monotonous non-decreasing function
2) Addition in which the correction amount calculated by the correction amount calculation unit and the change amount of the operation amount calculated by the slice operation amount calculation unit are added and output as the change amount of the current operation amount to the output control unit. An operation amount correction unit (80) having a correction unit (83), and an output control unit (60) for sending the operation amount smoothed by this operation amount correction unit to each slice as the current operation amount. A paper machine controller. 12. Slices (6, 7) arranged in the width direction of the paper for controlling the supply amount of the paper raw material, and a sensor (14) for measuring the quality of the manufactured paper in the width direction of the paper. ) With respect to the paper machine having, in the paper machine control device for operating the slice in a direction in which the value detected by this sensor matches a predetermined target profile, the measurement point of the sensor is one of the slices. A position corresponding part (34) for determining whether or not the position corresponds to, and a deviation between the detected basis weight profile and the target profile,
A profile calculator (32) that calculates the slice according to the correspondence relation of the position corresponding part, and a change amount of the operation amount for each slice for matching the measurement profile with the target profile from the calculation result of the profile calculator. Slice operation amount calculator (38)
And a rough operation amount calculation unit (84) that adds the amount of change in the operation amount obtained by the slice operation amount calculation unit and the previous operation amount output from the output control unit to the slice, the beginning and end of the slice. [0,1] with the coordinates normalized, and the basis function part (85) including a plurality of normalized spline functions in this interval, and the spline function of the basis function part A model matching unit (86) that approximates the operation amount calculated by the rough operation amount calculation unit, output control as the current operation amount of the slice by the spline function value at the coordinates corresponding to each slice obtained by this model matching unit The operation amount correction unit (80) having a slice corresponding unit (87) for outputting to the unit, and the output control unit (60) for sending the operation amount smoothed by the operation amount correction unit to each slice as the current operation amount. And is equipped with Paper machine control device according to claim and.