JP2672700B2 - Rolled material meandering control device - Google Patents

Description

Description: [Object of the Invention] (Industrial field of application) The present invention relates to a meandering control device for a rolled material rolled in a tandem rolling mill.

(Prior Art) As shown in FIG. 3, a meandering control device for rolled material is known. The meandering control device shown in FIG. 3 is a device for controlling the meandering of the rolled material 1 which is rolled by the rolling mill 2 and coming out therefrom, that is, the control for correcting the deviation in the flow direction of the rolled material 1. An operator side tension detector 3 and a drive side tension detector 4 are arranged on the inlet side of the rolling mill 2, and the rolling mill 2 is provided by these detectors 3 and 4.
The operator-side tension T ₃ and the drive-side tension T _{4 of the} rolled material 1 that is bitten by the are detected. Both tensions T ₃ and
The difference of T ₄ , that is, the tension deviation ΔT _i = T ₃ −T ₄ is calculated by the subtractor 5. The tension deviation ΔT _i is input to the accumulator 7 of the gain K after the dead zone is given to the minute deviation range by the dead zone device 6.

The dead zone device 6 has a dead zone of ΔT _i , a dead zone of ΔT _i , a dead zone of ΔT, a dead zone upper limit of T _UL , and a dead zone lower limit of T _LL. The tension deviation ΔT after processing is calculated by the following formula.

If T _UL <ΔT _i , ΔT = ΔT _i −T _UL (1) T _LL ≦ ΔT _i ≦ T _UL , ΔT = 0 (2) If T _i <T _LL , ΔT = ΔT _i −T _LL (3) The integrator 7 integrates the tension deviation ΔT output from the dead zone device 6 with a gain K, and the amount is a rolling position leveling amount for correcting the meandering of the rolled material 1. (Rolling machine 2
The deviation amount between the operator side rolling position and the drive side rolling position) is output as ΔL. However, since the rolling position leveling amount of the rolling mill 2 has a mechanical upper limit value and a lower limit value, the rolling position leveling amount ΔL output from the integrator 7 is subject to upper and lower limit processing by the absolute value limit device 8. Then, it is output as a limited rolling position leveling amount 8A. The subtractor 9 subtracts the limited rolling position leveling amount 8A from the operator side rolling position reference value set by the operator side rolling position reference value setting device 10 to obtain the operator side rolling position reference after the leveling amount correction. A value of 9A is obtained. Similarly, in the adder 11, by adding the limited rolling position leveling amount 8A to the drive side rolling position reference value set by the drive side rolling position reference value setting device 12, the drive side after leveling amount correction is added. A rolling position reference value of 11 A is obtained.

The operator side rolling position reference value 9A controls the operator side rolling position of the rolling mill 2 via the operator side rolling position control device 13 and the operator side rolling driving device 14. Similarly, the drive side reduction position of the rolling mill 2 is controlled by the drive side reduction position reference value 11A via the drive side reduction position control device 15 and the drive side reduction drive device 16.

In the meandering control device configured as described above, the operator side tension T ₃ detected by the tension detector ₃
Is greater than the drive side tension T ₄ detected by the tension detector 4, the elongation of the rolled material 1 on the operator side due to rolling is smaller than that on the drive side, so that the rolled material 1 meanders to the operator side ( Displacement)). In order to correct this meandering, on the one hand, the operator side rolling position reference value 9A after leveling amount correction is made small (that is, the rolling amount on the operator side is made large and the roll gap is made small), and on the other hand the leveling amount correction is made. By increasing the subsequent drive-side reduction position reference value 11A (that is, decreasing the drive-side reduction amount and increasing the roll gap) until the elongation of the rolled material 1 on the operator side becomes equal to that of the drive side. That is, the reduction control for the rolling mill 2 is continued until the operator side tension T ₃ and the drive side tension T ₄ become equal.

(Problems to be Solved by the Invention) In the conventional meandering control device described above, the deviation between the operator side tension T ₃ and the drive side tension T ₄ of the rolled material 1 on the inlet side of the rolling mill 2, that is, the tension. Deviation △
One input with tension deviation ΔT _i as control input and reduction position leveling amount 8A as control output so that T _i becomes zero.
/ 1 output type feed-forward control is performed. However, with the execution of this tension control, the deviation between the operator side rolling load and the drive side rolling load becomes large, which may adversely affect the strip thickness accuracy and the sectional shape of the rolled material 1.

Therefore, an object of the present invention is to maintain a deviation in tension between the operator side of the rolled material and the drive side, so that the deviation of the rolling load between the operator side of the rolling mill and the drive side does not become excessive, It is an object of the present invention to provide a meandering control device for a rolled material that can perform optimum meandering control within a range that does not adversely affect the plate thickness accuracy and the sectional shape of the rolled material.

[Configuration of the invention]

(Means for Solving the Problem) In order to achieve the above object, a meandering control device for rolled material according to the present invention provides a tension deviation between an operator side tension and a drive side tension of a rolled material that is caught in a rolling mill. A first calculation means for calculating, a second calculation means for calculating a rolling load deviation between a rolling load on the operator side of the rolling mill and a rolling load on the drive side of the rolling mill, and a tension calculated by the first calculation means. Third calculating means for calculating the rolling position leveling amount of the rolling mill and the polarity thereof by means of fuzzy inference for meandering control of the rolled material based on the deviation and the rolling load deviation calculated by the second calculating means. ,
And means for individually adjusting the reduction positions on the operator side and the drive side of the rolling mill based on the reduction leveling amount and the polarity calculated by the third calculation means.

(Operation) The only reason the conventional meandering control device had a bad influence on the strip thickness accuracy and cross-sectional shape of the rolled material was to eliminate the tension deviation between the operator side and the drive side of the rolled material. As a result, a 1-input / 1-output feedforward control system for operating the rolling position leveling amount of the rolling mill was constructed.

Therefore, in the present invention, when a tension deviation occurs between the operator side and the drive side of the rolled material that is caught in the rolling mill, the rolling load on the operator side and the drive side of the rolling machine when the tension deviation occurs The amount of reduction position leveling according to the deviation of is determined by using a fuzzy control method to perform meandering control.

That is, in the present invention, the following cases (a) to (d) regarding the combination of the polarity of the tension deviation and the polarity of the rolling load deviation will be considered.

(A) When the operator side tension of the rolled material is larger than the drive side tension and the operator side rolling load of the rolling mill is larger than the drive side rolling load, the rolling position on the operator side of the rolling mill is slightly tightened by the fuzzy control method. The rolling position leveling amount is set so that the rolling gap becomes smaller (the rolling gap becomes smaller).

(B) When the operator side tension of the rolled material is larger than the drive side tension and the operator side rolling load of the rolling mill is smaller than the drive side rolling load, the rolling position on the operator side of the rolling mill is greatly tightened by the fuzzy control method. Set the leveling amount for the rolling position.

(C) When the operator side tension of the rolled material is smaller than the drive side tension and the operator side rolling load of the rolling mill is larger than the drive side rolling load, the rolling position of the drive side of the rolling mill is greatly tightened by the fuzzy control method. Set the leveling amount for the rolling position.

(D) When the operator side tension of the rolled material is smaller than the drive side tension and the operator side rolling load of the rolling mill is smaller than the drive side rolling load, the rolling position on the drive side of the rolling mill is slightly tightened by the fuzzy control method. Set the leveling amount for the rolling position.

As described above, based on the tension deviation between the operator side of the rolled material and the drive side, and the rolling load deviation between the operator side of the rolling mill and the drive side,
To provide a meandering control device for rolled material capable of performing optimum meandering control that does not adversely affect the strip thickness accuracy and cross-sectional shape of the rolled material by obtaining the optimum reduction leveling amount by using a fuzzy control method. You can

(Example) Hereinafter, an example of the present invention is described with reference to drawings.

FIG. 1 shows an embodiment of the meandering control device of the present invention. In the meandering control device shown in FIG.
The parts designated by 6 and the reference signs 8 to 16 are the same as or correspond to the parts designated by the same reference numerals in the apparatus of FIG. The operator side tension T ₃ and the drive side tension T _{4 of the} rolled material 1 which is bitten into the rolling mill 2 are detected by the operator side tension detector 3 and the drive side tension detector ₄ , respectively. Both tension detectors 3 and 4
The subtractor 5 calculates the difference between the tensions T ₃ and T ₄ detected by the above, that is, the tension deviation ΔT _i = T ₃ −T ₄ . The tension deviation ΔT _i is given a dead zone by the dead zone device 6 to the minute deviation range, and its output signal ΔT is the first signal of the fuzzy inference device 17.
Input terminal. The dead zone device 6 performs dead zone processing on the tension deviation ΔT _{i in accordance} with the above-mentioned equations (1) to (3), and outputs the dead zone processed tension deviation ΔT.

The operator side rolling load detector 18 and the drive side rolling load detector 19 attached to the rolling mill 2 detect the operator side rolling load P ₁₈ and the drive side rolling load P ₁₉ of the rolling mill 2. The difference between the rolling loads P ₁₈ and P ₁₉ , that is, the rolling load deviation ΔP _i = P ₁₈ −P ₁₉ is the subtractor 20.
Is calculated by The rolling load deviation ΔP _i is provided with a dead zone by the dead zone device 21 with respect to the minute deviation range, and the output signal ΔP is the second zone of the fuzzy reasoning device 17.
Input terminal.

The dead zone device 21 defines the rolling load deviation before dead zone processing as ΔP _i , the dead zone upper limit value as P _UL , and the dead zone lower limit value as P _LL, and the rolling load deviation ΔP after dead zone processing is Calculate with an expression.

If P _UL <ΔP _i , ΔP = ΔP−P _UL (4) P _LL ≦ ΔP _i ≦ P _UL , ΔP = 0 (5) If P _i <P _LL , ΔP = Δ P _i −P _LL (6) The fuzzy inference device 17 uses the fuzzy inference method to perform the rolling position leveling of the rolling mill 2 based on the tension deviation ΔT after dead zone processing and the rolling load deviation ΔP after dead zone processing. Calculate the quantity ΔL. The details of the fuzzy inference method performed by the fuzzy inference apparatus 17 will be described later.

The reduction leveling amount ΔL calculated by the fuzzy inference device 17 is subjected to upper and lower limit processing by the upper and lower limit device 8 and is output from here as the upper and lower limited rolling position leveling amount 8A.

The reduction leveling amount 8A thus obtained is used to correct the reduction position reference for the rolling mill 2. That is, on the other hand, the operator side reduction position reference value 10A set by the operator side reduction position reference value setting device 10 is subtracted from the operator side reduction position reference value 10A by the subtractor 9.
A corrected operator side roll-down position reference value 9A (= 10A-8A) is formed by subtracting, and on the other hand, an adder is added to the drive-side roll-down position reference value 12A set by the drive-side roll-down position reference value setter 12. By adding the reduction leveling amount 8A by 11, the drive side reduction position reference 11A (= 12A + 8A) corrected is formed.

According to the operator side rolling position reference 9A, the operator side rolling position of the rolling mill 2 is controlled via the operator side rolling position control device 13 and the rolling driving device 14. Similarly, the drive-side reduction position of the rolling mill 2 is controlled via the drive-side reduction position control device 15 and the reduction driving device 16 according to the drive-side reduction position reference 11A.

Next, a fuzzy inference method performed by the fuzzy inference device 17 in the device shown in FIG. 1 will be described.

FIG. 2 shows fuzzy control rules and membership functions applied to the fuzzy reasoning device 17. Symbols shown in FIG.
A ₁₁ ,, A ₁₂ ,, A ₂₁ ,, A ₂₂ ,, A _31,, A ₃₂ , A ₄₁ , A ₄₂ , B ₁ , B ₂ , B ₃ and B ₄ respectively represent the membership function, and the sign
R ₁ , R ₂ , R ₃ and R ₄ each represent a fuzzy control rule. Here, the explanation will be made assuming that the inference method using the MIN arithmetic method is applied.

Now, the input (premise) for inference is the tension deviation ΔT and the rolling load deviation ΔP, the output (conclusion) is the rolling position leveling amount ΔL of the rolling mill 2, and the input (premise) and the output (conclusion) are connected. What are fuzzy control rules R ₁ , R ₂ , R ₃ and R ₄ . Now, let us say that the specific value of the tension deviation ΔT is ΔT ₁ , the specific value of the rolling load deviation ΔP is ΔP ₁ , and the specific value of the rolling position leveling amount ΔL is ΔL ₁ .

(Premise): ΔT = ΔT ₁ and ΔP = ΔP ₁ (fuzzy control rule) R ₁ : If ΔT = A ₁₁ and ΔP = A _12, then ΔL = B ₁ .

R ₂ : If ΔT = A ₂₁ and ΔP = A _22, then ΔL = B ₂ .

R ₃ : If ΔT = A ₃₁ and ΔP = A _32, then ΔL = B ₃ .

R ₄ : If ΔT = A ₄₁ and ΔP = A _42, then ΔL = B ₄ .

(Conclusion): ΔL = ΔL ₁ .

Next, the fuzzy control rule and the membership function described above will be described.

(A) The fuzzy control rule R ₁ membership function A ₁₁ indicates that the operator side tension T ₃ is larger than the drive side tension T ₄ , and the horizontal axis indicates the tension deviation ΔT (= T ₃ −T ₄ ). The vertical axis indicates the degree of conformity.

Membership function A ₁₂ is operator side rolling load P
_{When 18} is larger than the drive side rolling load P ₁₉ , the operator side rolling load is variable, and the horizontal axis shows the rolling load deviation ΔP (= P ₁₈ −P ₁₉ ).
The vertical axis represents the goodness of fit.

The membership function B ₁ is a membership function for setting a reduction position leveling amount that slightly tightens the reduction position on the operator side of the rolling mill 2.

Membership function A ₁₁ tension deviation ΔT =
The fitness for ΔT ₁ is compared with the fitness for a certain rolling load deviation ΔP = ΔP ₁ of the membership function A ₁₂ , and the membership function B ₁ is cut at the smaller fitness. . Cut membership function B ₁
The ΔL coordinate of the center of gravity of the figure is the rolling position leveling amount ΔL of the rolling mill 2 inferred by the fuzzy control rule R ₁ (the direction of tightening the rolling position on the operator side is positive).

(B) The fuzzy control rule R ₂ membership function A ₂₁ indicates that the operator side tension T ₃ is larger than the drive side tension T _4, and the horizontal axis indicates the tension deviation ΔT (= T ₃ −T ₄ ). And the vertical axis represents the degree of conformity.

Membership function A ₂₂ is driveside rolling load P
_{When 19} is larger than the operator side rolling load P ₁₈ ,
It shows the adaptability that the operator side rolling load can be changed. The vertical axis represents rolling load deviation ΔP (= P ₁₈ −P ₁₉ ),
The vertical axis represents the goodness of fit.

The membership function B ₂ is a membership function for setting the amount of reduction position leveling so as to greatly tighten the reduction position on the operator side of the rolling mill 2.

Tension deviation of a certain value of membership function A ₂₁ △ T = △ T
_The goodness of fit to ₁ is compared with the goodness of fit of a certain value of the membership function A ₂₂ to the rolling load deviation ΔP = ΔP ₁ , and the membership function B ₂ is cut at the smaller fitness. The ΔL coordinate of the center of gravity of the figure of the cut membership function B ₂ is inferred by the fuzzy control rule R ₂ and the rolling position leveling amount ΔL of the rolling mill 2 (the direction of tightening the rolling position on the operator side is positive. ).

(C) The fuzzy control rule R ₃ membership function A ₃₁ indicates the degree to which the drive side tension T ₄ is larger than the operator side tension T ₃ . The horizontal axis indicates the tension deviation ΔT (= T ₃ −T ₄ ), and the vertical axis indicates the degree of conformity.

The membership function A ₃₂ is defined as follows: when the operator side rolling load P ₁₈ is larger than the drive side rolling load P ₁₉ ,
The degree to which the drive side rolling load can be changed is shown. The horizontal axis represents the rolling load deviation ΔP (= P ₁₈ −P ₁₉ ), and the vertical axis represents the compatibility.

The membership function B ₃ is a membership function for setting the amount of reduction position leveling so as to greatly tighten the reduction position on the drive side of the rolling mill 2.

Membership function A ₃₁ of tension deviation ΔT =
And fit to △ T _1, by comparing the degree of conformity membership functions rolling load difference △ P = △ P ₁ value of A _32, to cut the membership function B ₃ at the smaller goodness of fit . Cut membership function B ₃
The ΔL coordinate of the center of gravity of the figure is the rolling position leveling amount ΔL of the rolling mill 2 inferred by the fuzzy control rule R ₃ (the direction in which the rolling position on the operator side is tightened is positive).

(D) The fuzzy control rule R ₄ membership function A ₄₁ indicates the degree to which the drive side tension T ₄ is larger than the operator side tension T ₃ . The horizontal axis indicates the tension deviation ΔT (= T ₃ −T ₄ ), and the vertical axis indicates the degree of conformity.

Membership function A ₄₂ is driveside rolling load P
_{When 19} is larger than the operator side rolling load P ₁₈ ,
The degree to which the drive side rolling load can be changed is shown. The horizontal axis shows the rolling load deviation ΔP (= P ₁₈ −P ₁₉ ), and the vertical axis shows the goodness of fit.

The membership function B ₄ is a membership function for setting the amount of reduction position leveling that slightly tightens the reduction position on the drive side of the rolling mill 2.

Membership function A ₄₁ tension deviation ΔT =
The goodness of fit for ΔT ₁ is compared with the goodness of fit for a certain value of the membership function A ₄₂ , ΔP = ΔP ₁ , and the membership function B ₄ is cut at the smaller one. The ΔL coordinate of the center of gravity Q of the figure of the cut membership function B ₄ is inferred by the fuzzy control rule R ₄ and the rolling position leveling amount ΔL of the rolling mill 2 is ΔL (the direction of tightening the rolling position on the operator side is positive. Yes).

Membership function that means the reduction position leveling amount ΔL cut by the fuzzy control rules R ₁ , R ₂ , R ₃ , R ₄
The ΔL coordinate of the center of gravity Q of the figure of the new membership function B ₀ created by superimposing B ₁ , B ₂ , B ₃ , and B ₄ is the fuzzy control rule R ₁ , R ₂ , R ₃ , and R _4. Rolling machine inferred by
It becomes the set value of the rolling position leveling amount ΔL.

The process of obtaining the rolling position leveling amount ΔL ₁ when the tension deviation ΔT is ΔT = ΔT ₁ and the rolling load deviation ΔP is ΔP = ΔP ₁ will be described with reference to FIG. .

(E) Inference by fuzzy control rule R _{1 When} ΔT = ΔT ₁ , the goodness of fit obtained by the membership function A ₁₁ is ω ₁ .

When ΔP = ΔP ₁ , the goodness of fit obtained by the membership function A ₁₂ is ω ₂ .

In this example, since ω ₁ <ω ₂ , the membership function B ₁ is cut at the goodness of fit ω ₁ , so that the hatched portion of the membership function B ₁ is reduced by the fuzzy control rule R _1. It is a membership function that means the position leveling amount ΔL.

(F) Inference by fuzzy control rule R _{2 When} ΔT = ΔT ₁ , the goodness of fit obtained by the membership function A ₂₁ is ω ₃ .

When ΔP = ΔP ₁ , the goodness of fit obtained by the membership function A ₂₂ is ω ₄ .

In this example, since ω ₄ <ω ₃ , the membership function B ₂ is cut at the goodness of fit ω ₄ , so the hatched portion of the membership function B ₂ is the fuzzy control rule.
It is a membership function that means the reduction position leveling amount ΔL inferred from R ₂ .

(G) Inference by fuzzy control R _{3 When} ΔT = ΔT ₁ , the goodness of fit obtained by the membership function A ₃₁ is zero. Therefore, the reduction position leveling amount Δ inferred by the fuzzy control rule R ₃
There is no membership function meaning L.

(H) Inference by fuzzy control R _{4 When} ΔT = ΔT ₁ , the goodness of fit obtained by the membership function A ₄₁ is zero. Therefore, there is no membership function that means the amount of rolling position leveling inferred by the fuzzy control rule R ₄ .

Therefore, in the above example, the hatched portion of the membership function B ₁ meaning the rolling position leveling amount ΔL inferred by the fuzzy control rule R ₁ and the rolling position leveling amount ΔL inferred by the fuzzy control rule R ₂ meaning membership functions B membership functions B ₀ created by the _second superposing the hatched portion of the center of gravity Q of figure △ L coordinates to the tension deviation △ T is, △ T = △ T ₁
Then, the rolling load deviation ΔP is a set value of the rolling position leveling amount ΔL of the rolling mill 2 for correcting the meandering of the rolled material 1 when ΔP = ΔP ₁ .

The present invention is not limited to the specific embodiment described above, and can be implemented by the following modified examples.

(1) Membership functions A ₁₁ , A ₁₂ , A ₂₁ , shown in FIG.
A ₂₂ ,, A _31,, A ₃₂ , A ₄₁ , A ₄₂ , B ₁ , B ₂ , B ₃ , B ₄ are adjusted each time the present invention is applied to a plant, and are members of FIG. The shape of the ship function can be appropriately changed and implemented.

(2) Membership function A ₁₁ , A ₂₁ , A ₃₁ , A _{41 in} Fig. 2
Means a tension deviation, but the number can be appropriately added by applying a finer case classification when applying the present invention to a plant.

(3) Similarly, the membership functions A ₁₂ , A ₂₂ , A shown in FIG.
₃₂ and A ₄₂ mean rolling load deviations, but the number can be appropriately added by applying a finer case when applying the present invention to a plant.

〔The invention's effect〕

As described above, according to the present invention, to correct the meandering at that time from the tension deviation between the operator side and the drive side of the rolled material on the rolling mill entrance side and the rolling load deviation between the operator side and the drive side. A feedforward that can optimally correct the meandering of the rolled material without adversely affecting the strip thickness accuracy and cross-sectional shape of the rolled material by determining and controlling the required amount of reduction position leveling by fuzzy reasoning method. It is possible to realize the meandering control device.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a meandering control device for rolled material according to the present invention, FIG. 2 is a diagram for explaining the operation of a fuzzy reasoning portion in the meandering control device of FIG. 1, and FIG.
FIG. 1 is a block diagram showing a conventional meandering control device for rolled material. 1 ... Rolled material, 2 ... Rolling machine, 3 ... Operator side tension detector, 4 ... Drive side tension detector, 5,9,20
…… Subtractor, 10 …… Operator side rolling position reference value setting device, 11 …… Adder, 12 …… Drive side rolling position reference value setting device, 13, 15 …… Rolling position control device, 14 …… Operator side Rolling down drive, 16 …… Drive side rolling down drive, 17 …… Fuzzy reasoning device, 18 …… Operator side rolling load detector, 19 …… Drive side rolling load detector.

Claims (1)

(57) [Claims] 1. A tension detecting means for detecting an operator side tension and a drive side tension of a rolled material bitten into a rolling mill, and a rolling load detecting means for detecting an operator side rolling load and a drive side rolling load of the rolling mill. A first calculation means for calculating a tension deviation between the operator side tension and the drive side tension detected by the tension detection means, and an operator side rolling load and a drive side rolling load detected by the rolling load detection means Second rolling means for calculating a rolling load deviation between the rolling material and the rolling deviation based on the tension deviation calculated by the first calculating means and the rolling load deviation calculated by the second calculating means. The rolling position leveling amount of the rolling mill and its polarity for the meandering control of the rolling mill by means of fuzzy reasoning. And a means for individually adjusting the reduction positions on the operator side and the drive side of the rolling mill based on the reduction position leveling amount and the polarity calculated by the third calculation means. Rolling material meandering control device.