KR101439697B1 - System and method for controlling strip deviation - Google Patents

Abstract

The present invention relates to a plate positioning control system and method, wherein the plate positioning control system is provided at an entrance of a rolling stand and measures a plate positioning information of a steel plate entering the rolling stand. A thickness meter provided on the exit side of the rolling stand for measuring crown information of the steel plate passed through the rolling stand; A flection calculating unit for calculating a fade-out value by using the focal point information and the crown information received from the focal point measuring unit and the thickness gauge, respectively; A pan and tilt controller for estimating the rolling machine control value of the next step according to an iterative learning control using the pan-tilt value received from the pan-tilt calculator; And a rolling roll level control unit for controlling the roll level of the rolling mill in accordance with the rolling mill control value transmitted from the plate leveling control unit.

Description

TECHNICAL FIELD [0001] The present invention relates to a system and a method for controlling a substrate,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a plate tilt control technique, and more particularly, to a tilt control system and method using iterative learning control.

In case of the plate rolling in the final stand of the finishing mill in the hot rolling line, the stability of the plate and the shape of the product sharply deteriorate.

Therefore, the plate tilt control in the hot rolling line is directly related to the productivity, but conventionally, the tilt of the plate is controlled mainly by manual intervention of the operator, that is, by manually changing the roll gap level of the rolling mill.

In addition, there is a limitation in that the model of the rolling mill system is inaccurate, or it is difficult to stably control the plate stiffness when the rolling mill system changes over time.

Therefore, in the related art, there is a demand for a method for stably controlling the plate stiffness in order to improve the productivity.

In order to solve the above problems, a first aspect of the present invention provides a plate-spread control system. Wherein the plate positioning control system comprises a plate tilting measuring unit provided at an inlet side of the rolling stand for measuring plate tilting information of a steel plate entering the rolling stand; A thickness meter provided on the exit side of the rolling stand for measuring crown information of the steel plate passed through the rolling stand; A flection calculating unit for calculating a fade-out value by using the focal point information and the crown information received from the focal point measuring unit and the thickness gauge, respectively; A pan and tilt controller for estimating the rolling machine control value of the next step according to an iterative learning control using the pan-tilt value received from the pan-tilt calculator; And a rolling roll level control unit for controlling the roll level of the rolling mill in accordance with the rolling mill control value transmitted from the plate leveling control unit.

 The plate tangent calculation section calculates the plate tangent

는 k번째 압연기 제어 값에 따라 상기 압연기 롤 레벨을 제어한 후, 상기 판쏠림 측정부에 의해 측정한 k번째 판쏠림 정보를 의미하고,

는 k번째 압연기 제어 값에 따라 상기 압연기 롤 레벨을 제어한 후, 상기 두께계에 의해 측정한 k번째 크라운 정보를 의미하고, y_k는 상기 k번째 판쏠림 정보 및 k번째 크라운 정보를 이용하여 계산한 k번째 판쏠림 값을 의미하고,

는 y_k를 계산함에 있어

및

의 가중치를 결정하기 위해 기 설정된 필터 계수(0≤

≤1)를 의미한다.The plate-to-plate value can be calculated according to the following equation:

Refers to kth plate spreading information measured by the plate displacement measuring unit after controlling the rolling mill roll level according to the kth rolling mill control value,

And y _k denotes the k th crown information measured by the thickness gauge after controlling the mill roll level according to the k th rolling control value and y _k is calculated using the k th rolling information and the k th crown information A k-th plate mean value,

Is used to calculate y _k

And

Lt; / RTI >< RTI ID = 0.0 >

≪ / = 1).

Wherein the plate tilt control unit comprises: a storage unit for storing the k th rolling control value and the k th rolling value; And an iterative learning control unit for calculating the (k + 1) -th rolling mill control value using the iteration control using the k-th rolling control value and the k-th rolling control value stored in the storage unit.

Wherein the iterative learning control unit calculates the following equation

And

는 기 설정된 스텝 사이즈, e_k는 k번째 에러 값, y_k는 k번째 판쏠림 값, 그리고

는 기 설정된 목표 판쏠림 값을 의미한다.
, The control value of the (k + 1) th rolling mill may be calculated according to the following equation: u _k =

E _k is the kth error value, y _k is the k th plateau value, and

Means a predetermined target deviation value.

In addition, a second aspect of the present invention provides a method of controlling plate stiffness. The plate-thrusting control method includes: measuring the k th plate-spreading information and the kth crown information at the entrance and exit of the rolling mill after controlling the mill roll level according to the control value of the k th rolling mill; Calculating a kth plateauing value using the kth plateauing information and the kth crown information; Calculating a control value of a (k + 1) -th rolling mill according to an iterative learning control using the kth plate tilt value; And controlling the rolling mill roll level according to the (k + 1) th rolling mill control value.

The step of calculating the (k + 1) -th rolling mill control value includes: calculating a kth error value by comparing the kth plateauing value with a target plateauing value; And calculating the (k + 1) th rolling mill control value using the kth error value.

And determining whether there is a change in the amount of plate deflection after the step of controlling the roll level of the rolling mill. If it is determined that there is a change in the plate deflection amount, the k value is increased by 1, And returns to the step of measuring the skip information and the kth crown information, respectively.

In addition, the means for solving the above-mentioned problems are not all enumerating the features of the present invention. The various features of the present invention and the advantages and effects thereof will be more fully understood by reference to the following specific embodiments.

A plate tilt control system and method that can stably control plate treading can be provided if the rolling system model is not accurate or if the rolling mill system changes over time.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram of a plate tilt control system according to an embodiment of the present invention;
FIG. 2 is a diagram showing a detailed configuration of a plate focusing control unit using an iterative learning control according to an embodiment of the present invention,
FIG. 3 is a flowchart of a plate tilt control method according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, in order that those skilled in the art can easily carry out the present invention. In the following detailed description of the preferred embodiments of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. In the drawings, like reference numerals are used throughout the drawings.

In addition, in the entire specification, when a part is referred to as being 'connected' to another part, it may be referred to as 'indirectly connected' not only with 'directly connected' . Also, to "include" an element means that it may include other elements, rather than excluding other elements, unless specifically stated otherwise.

1 is a configuration diagram of a plate tilt control system according to an embodiment of the present invention.

1, a plate positioning control system according to an embodiment of the present invention includes a plate positioning measuring unit 110, a thickness meter 120, a plate positioning calculation unit 130, a plate positioning control unit 140, And a level control unit 150.

The plate tilt measurement unit 110 is provided at the entrance of the hot finish rolling final stand 20 so that when the steel plate 1 passes through the hot finishing rolling front stage 10 and enters the hot finishing rolling final stand 20 Measures plate movement information of the steel plate in the width direction of the steel plate and transmits the measured plate positioning information to the plate positioning calculation unit 130. [ The platelet measuring unit 110 may be implemented by a plurality of video meters.

The thickness gauge 120 is provided on the exit side of the hot finish rolling final stand 20 and is provided with thickness information in the width direction with respect to the steel plate 1 that has passed through the hot finish rolling final stand 20, And transmits the measured crown information to the calculation unit 130. The calculation unit 130 calculates the crown information based on the crown information.

The plate tilt calculation unit 130 receives the plate tilt information and the crown information from the tilt measuring unit 110 and the thickness gauge 120, calculates an output signal according to Equation 1, And outputs it to the control unit 140.

[Equation 1]

Here, y _k is a value obtained by controlling the roll level of the rolling mill according to the output signal for the k-th input, that is, the k-th rolling mill control value (roll level value) And a plate-to-plate value calculated by using the plate-spreading information and the crown information measured by the cue information.

는 k번째의 압연기 제어 값(롤 레벨 값)에 따라 압연기의 롤 레벨을 제어한 후, 판쏠림 측정부(110)에 의해 측정한 판쏠림 정보를 의미한다.Also,

Means plate-spread information measured by the plate-spread measuring unit 110 after controlling the roll level of the rolling mill according to the k-th rolling mill control value (roll level value).

는 k번째의 압연기 제어 값(롤 레벨 값)에 따라 압연기의 롤 레벨을 제어한 후, 두께계(120)에 의해 측정한 크라운 정보를 의미한다.Also,

Means the crown information measured by the thickness gauge 120 after controlling the roll level of the rolling mill according to the kth rolling mill control value (roll level value).

는 필터 계수를 의미하는 것으로, 출력 신호 y_k를 도출함에 있어

및

의 가중치를 결정하기 위한 것이며, 제어 담당자에 의해 0≤

≤1의 범위에서 미리 설정될 수 있다
Also,

Means a filter coefficient, and in deriving the output signal y _k

And

Is determined by the person in charge of control < RTI ID = 0.0 > 0 < / RTI &

≪ / RTI >< RTI ID = 0.0 >

Plate displacement control section 140 includes a plate displacement receiving plate displacement value transmitted from the calculation unit 130, that is, the output signal y _k by using iterative learning control (iterative learning control) in accordance with (k + 1) th rolling mill control value, that is, the input signal u _{k + 1} .

The detailed configuration and method for estimating the (k + 1) -th input signal u _{k + 1} according to the iterative learning control will be described in detail with reference to FIG. 2 and FIG. 3.

The roll roll level control unit 150 is for controlling the roll level of the rolling mill according to the rolling mill control value transmitted from the roll steepness control unit 140, thereby controlling the plate rolling in the final stage of the hot rolling rolling.

The sheet thickness measuring unit 110 and the thickness meter 120 are provided at the entrance and exit of the hot finish rolling final stand 20 in the above description. However, the present invention is not limited to this, 110 and the thickness gauge 120 may be installed at the entrance and exit of the rolling stand for measuring the plate spread.

2 is a diagram showing a detailed configuration of a plate-spread control unit using an iterative learning control according to an embodiment of the present invention.

2, the plate tilting control unit 140 may include a storage unit 141 and an iterative learning control unit 142. As shown in FIG.

The storage unit 141 controls the roll level of the rolling mill according to the k-th input signal u _k of the rolling mill 200, that is, the k-th rolling mill control value and the k-th output signal y _k , And the plate saturation values calculated by using one plate saturation information and crown information are respectively stored.

The iterative learning control unit 142 uses the k-th input signal u _k and the k-th output signal y _k stored in the storage unit 141 to generate k + 1-th input And calculates the signal u _{k + 1} .

&Quot; (2) "

&Quot; (3) "

는 스텝 사이즈를 의미하는 것으로, k+1번째 압연기 제어 값을 계산함에 있어 k번째 에러 값의 가중치를 나타내며, 기 설정된 상수 값을 가진다.here,

Represents the step size, and represents the weight of the kth error value in calculating the (k + 1) th rolling mill control value, and has a predetermined constant value.

Also, the initial value u ₀ has a very small constant value.

In addition, e _k means a k-th error value.

In addition, y _d means a required reference output value, that is, a target value of a plateauing value, which can be preset by an administrator according to a requirement.

According to Equation 2, and 3, the more steps are repeated displacement plates and the output signal y _k and the reference output value y _d mill input signal at every step as a decline in the error between the direction of the calculating unit 130 are newly calculated. Thus, the rolling machine system model may change after a predetermined time, or the rolling mill input signal may be obtained which, if not accurate, minimizes the error.

FIG. 3 is a flowchart of a plate tilt control method according to another embodiment of the present invention.

Referring to FIG. 3, first, the plate-positioning control step is initialized, that is, k = 0 is initialized (S10).

Thereafter, the rolling machine receives the roll level value which is the control value of the kth rolling mill (S20), and controls the roll level of the rolling mill accordingly.

Then, the plate-spreading information and the crown information of the steel sheet are measured at the entrance and exit of the rolling mill (S30).

Then, the kth output signal of the rolling mill, that is, the plate stiffness value is calculated according to Equation (1) using the measured plate stiffness information and crown information of the steel strip (S40).

Then, a kth error value is calculated according to Equation (3) (S50), and a roll control value of a k + 1th roll level value, i.e., the next step is calculated using the kth error value (S60).

Thereafter, the mill roll level is controlled in accordance with the rolling control value of the next step calculated (S70), and it is determined whether there is a change in the plate displacement amount (S80).

If it is determined that a change in the plate stiffness occurs, the process proceeds to the next step, that is, increases the value of k by 1, and then returns to step S20 and repeats the above-described process.

The above-described process is repeated until there is no change in the plate stiffness, thereby suppressing the plate stiffness.

According to the above-described embodiment of the present invention, by using the iterative learning control, it is possible to stably control the plate stiffness even when the model of the rolling mill machine system is not accurate or the rolling mill system changes over time, It is possible to improve the throughput to lower the error rate and thereby to improve the operational error rate.

The present invention is not limited to the above-described embodiments and the accompanying drawings. It will be apparent to those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

1: steel plate
10: Hot finish rolling final stand
20: Hot-finished rolled shear stand
110:
120: thickness meter
130:
140:
150: Mill roll level control unit

Claims (7)

A plate tipping measuring unit provided at an entrance of the rolling stand for measuring plate tilt information of a steel plate entering the rolling stand;
A thickness meter provided on the exit side of the rolling stand for measuring crown information of the steel plate passed through the rolling stand;
A pan and tilt calculator for calculating pan and tilt values of a current step using the pan and pan information and crown information received from the pan and pan measuring unit and the thickness meter, respectively;
A pan and tilt controller for estimating the rolling control value of the next step according to the iterative learning control using the pan-tilt value of the current step transmitted from the pan-tilt calculation unit; And
And a roll roll level control unit for controlling the roll level of the rolling mill in accordance with the rolling mill control value received from the plate leveling control unit.
The apparatus according to claim 1, wherein the plate-
The following equation

Calculates the plate-spreading value according to the following equation,

Refers to kth plate spreading information measured by the plate displacement measuring unit after controlling the rolling mill roll level according to the kth rolling mill control value,

Indicates the kth crown information measured by the thickness gauge after controlling the mill roll level according to the kth rolling mill control value,
y _k denotes a k th plateau value calculated using the k th plateau information and the kth crown information,

Is used to calculate y _k

And

Lt; / RTI >< RTI ID = 0.0 >

≪ / = 1)
Wherein the kth means the current step.
The apparatus according to claim 2, wherein the plate-
A storage unit for storing the k th rolling control value and the k th rolling value; And
And an iterative learning control unit for calculating a control value of a (k + 1) th rolling mill using an iterative learning control using the k th rolling control value and the k th rolling control value stored in the storage unit,
And the (K + 1) th step means the next step.
4. The apparatus according to claim 3,
The following equation,

And

1) -th rolling mill control value,
u _k is the k th rolling mill control value, K is the predetermined step size, e _k is the k th error value, y _k is the kth plateauing value, and y _d is the predetermined target plateauing value. .
measuring the k th plateau information and the kth crown information at the entrance and exit of the mill after controlling the mill roll level according to the k th rolling mill control value;
Calculating a kth plateauing value using the kth plateauing information and the kth crown information;
Calculating a control value of a (k + 1) -th rolling mill according to an iterative learning control using the kth plate tilt value; And
And controlling the rolling mill roll level according to the (k + 1) th rolling mill control value.
6. The method of claim 5, wherein calculating the (k + 1) th rolling mill control value comprises:
Calculating a kth error value by comparing the kth plateauing value with a target plateauing value; And
And calculating the (k + 1) th rolling mill control value using the kth error value.
6. The method of claim 5, wherein after controlling the mill roll level,
Further comprising the step of confirming whether there is a change in the plate deflection amount,
And if there is a change in the amount of plate deflection as a result of the determination, returning to the step of measuring the kth plateauing information and the kth crown information after the k value is increased by one.

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