JP3057979B2 - Catenary control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catenary control device in a steel process line or the like.

[0002]

2. Description of the Related Art Conventionally, in catenary control in a steel process line or the like, a bridle roll is provided on each of an entrance side and an exit side of a catenary loop, and a speed command and a torque command are given to the bridle roll to keep the catenary loop constant. I keep it. Specific control includes a tension control method in which a tension detector is installed in a catenary zone to maintain a constant tension, and a height control method in which a catenary sensor is installed to maintain a constant height.

In these controls, when the thickness of a material such as a steel plate constituting the catenary changes and the cross-sectional area fluctuates, as the welding point connecting the preceding material and the following material passes through the catenary zone, Changes. FIG. 4 schematically shows the change. The catenary shape shown by a solid line in the figure indicates a case where the cross-sectional area of the material forming the catenary is constant, and the broken line indicates that the cross-sectional area of the preceding material is larger than that of the following material. The chain line shows the case where the cross-sectional area of the preceding material is smaller than the cross-sectional area of the following material.

[0004] Since the catenary shape changes as the welding point passes, the material comes into contact with the structural obstacle at the changed portion as it is. Therefore, it is necessary to control the catenary shape by controlling the tension in the case of the tension control and controlling the height in the case of the height control. For example, in the case of the tension control, the tension set value is corrected by a simulation to keep the distance between the catenary and the structural obstacle constant, the variation Δh in all the catenary zones is minimized, or the lowest point ( The position of the bottom dead center can be kept constant. Specifically, assuming that the tension set value of the preceding material is T ₁ , the tension set value of the following material is T ₂ , and the position of the welding point is x using the correction curve shown in FIG. 5, the optimal tension set value T ^* Is determined by the following equation.

[0005]

## EQU1 ## T ^* = T ₁ + d (x) · (T ₂ −T ₁ )

According to this formula, at the start point, the optimum tension set value T ^* becomes T ₁ , and at the end point, the optimum tension set value T ^* becomes T ^*.
But the T _2.

[0007]

However, when the catenary shape is to be controlled by height control, the correction curve becomes as shown in FIG. 6, and the correction curve changes depending on the ratio of the cross-sectional areas. Moreover, this change is not simply proportional to the cross-sectional area ratio. Therefore, conventionally, there has been a problem that it is necessary to prepare a large number of correction curves, and it is difficult to obtain an optimum correction value. The present invention has been made in order to solve the above-described problems, and an object of the present invention is to provide a catenary control device that can easily obtain an optimum correction value of a height set value in height control. is there.

[0008]

In order to achieve the above object, the present invention provides a catenary sensor for detecting a catenary height at a fixed point in a catenary zone, and an optimal value of the catenary height at a fixed point in the catenary zone is input to an external input. And a means for detecting a welding point position when a welding point connecting different materials having different characteristics when forming a catenary enters the catenary zone, and a welding prepared in advance. With reference to the tension correction curve showing the relationship between the point position and the optimal tension set value for it,
Means for calculating the optimum tension set value at the detected welding point position, and a catenary curve formula for each of the preceding material forming the front catenary and the following material forming the rear catenary of the welding point in the catenary zone, the welding point position A means for calculating from the optimum tension set value and the known preceding material unit weight, the succeeding material unit weight, and the catenary span, and the catenary height at the fixed point using the corresponding catenary curve equation according to the position of the welding point with respect to the fixed point. Means for calculating a height, a subtraction means for calculating a height correction amount by subtracting the set catenary height optimum value from the calculated catenary height, and a catenary height detected by the height correction amount and the catenary sensor. Means for calculating a correction amount of the tension in the front bridal roll from the above.

[0009]

In the present invention, the catenary height at the fixed point of the catenary zone is detected by the catenary sensor, and the optimum value of the catenary height at the fixed point is set by the height setting device. When a welding point formed by connecting dissimilar materials having different properties when forming a catenary enters the catenary zone, the position of the welding point is detected. Then, the optimum tension setting value at the detected welding point position is calculated with reference to a tension correction curve indicating the relationship between the welding point position prepared in advance and the optimum tension setting value corresponding thereto.

At the same time, a catenary curve formula for each of the preceding material forming the front catenary of the welding point in the catenary zone and the following material forming the rear catenary is calculated based on the detected welding point position, the calculated optimum tension set value and It is calculated from the known preceding material unit length weight, the following material unit length weight, and the catenary span. Next, the catenary height at the fixed point is calculated by using the catenary curve equation corresponding to the position of the welding point with respect to the fixed point.

Further, the set catenary height optimum value is subtracted from the calculated catenary height to calculate a height correction amount, and the height correction amount is calculated from the obtained height correction amount and the catenary height detected by the catenary sensor. The correction amount of the tension in the bridal roll located ahead is calculated. As a result, the catenary height can be controlled by obtaining the optimum height of the fixed-point catenary with only one simulation.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing the configuration of the embodiment of the present invention.
In the figure, a catenary C to be controlled includes a guide roller 2 disposed immediately after a main bridle roll 1 and a guide roller 3 disposed immediately before a sub bridle roll 4.
Is formed between The space between the guide rollers 2 and 3 is a catenary zone, and the height of the catenary C at a specific position (hereinafter, referred to as a fixed point) in the catenary zone is detected by the catenary sensor 5.

Catenary C is composed of bridle rolls 1, 4
Is controlled by That is, when the speed command value Nmref is input to the speed control unit 6, the speed control unit 6 controls the rotation of the motor 7 based on the speed command value Nmref, so that the bridle roll 1 is driven at a predetermined tension and speed. You. On the other hand, as for the bridle roll 4, in a normal case where the same material is continuously fed to form the catenary C, the catenary sensor 5 is set based on the set value Href of the catenary height set by the height setting device 8. The actual measured value Hist of the detected catenary height is subtracted by the subtractor 9, and the obtained difference is sent to the height control controller 11.

The height control adjuster 11 converts the input difference into a speed command value Nhref and sends it to the speed controller 12. The speed control unit 12 controls the rotation of the motor 13 based on the input speed command value Nhref. Thereby, the tension and speed of the bridle roll 4 are controlled, and the optimal catenary C is formed. The droop resistance 14 is added to the speed control unit 12 in parallel, so that a drooping characteristic is added.

When different materials pass through, the position of the welding point connecting the ends of the different materials into the catenary zone is detected by a detecting means (not shown), and the optimum tension setting in the height correction circuit 15 is performed. The value is input to the value calculator 16. The tension correction curve similar to that shown in FIG. 5 is stored in advance in the calculation unit 16, and by referring to this correction curve, the optimum tension set value T ^* is calculated, and the height correction calculation unit It is sent to 17. Height correction calculation unit 1
At 7, the catenary height Href 'at the fixed point where the catenary sensor 5 is installed is calculated based on the optimum tension set value T ^* after one of the catenary formulas described later is selected according to the position of the welding point. You.

Next, the subtractor 18 subtracts the catenary height set value Href set by the height setter 8 from the catenary height Href ', and obtains the difference ΔH
ref is sent to the adder 19. The adder 19 calculates the difference Δ
The set value Href is further added to Href, and the obtained sum is sent to the subtractor 9. Thereafter, as described above, the speed of the bridle roll 4 is controlled, and the catenary height at the fixed point of the catenary C is maintained at the set value Href.

Next, an expression representing a catenary curve used in the height correction calculating section 17 will be described with reference to the explanatory diagram of FIG. In FIG. 2, guide rollers 2,
The curve formula of the catenary C formed between 3 is as follows when the running materials are the same.

[0018]

(Equation 2)

S _A and D _A in the equations are represented by the following equations, respectively.

[0020]

(Equation 3)

[0021]

(Equation 4)

Here, T in Equations 2 to 4 is a tension set value (k
g), W is the material weight (kg / m), S is the catenary span (m), x is the height from the start of the catenary (m), y
Is the horizontal distance (m) from the starting point of the catenary, and H is the vertical distance (m) between the guide rollers 2 and 3. Further, when the welding point enters the catenary zone, the catenary formula of the following material is as shown in Expression 5, and the catenary expression of the preceding material is as shown in Expression 6. In the equation, x _z is the position of the welding point (horizontal distance m), W ₁ is the weight of the preceding material (kg / m), and W ₂ is the weight of the following material (kg / m).

[0023]

(Equation 5)

[0024]

(Equation 6)

Here, S _B , D _B , S _A , and D _A in Expressions 5 and 6 are used.
Are represented by the following equations.

[0026]

S _B = a ₁ · (S−x _z ) ² + x _z + a ₂ · x _z ² + a ₃ · T

[0027]

## EQU8 ## D _B = a ₄ · S _B ² · 1 / T

[0028]

S _A = x _z + a ₅ · (x _z -S _B )

[0029]

Equation 10] _{D A = -a 4 · x z} 2 · 1 / T + 2 · a 4 · S B ·
x _z · 1 / T + a ₆ · (x _z −S _B ) ² · 1 / T

Here, a _{1 to} a ₆ in Equations 7 to 10 are all constants, and are as follows.

[0031]

[Number 11] _{a 1 = W 2/2 ·} W 2 · S

[0032]

## EQU12 ## a ₂ = − ／ · S

[0033]

## EQU13 ## a ₃ = −H / W ₂ · S

[0034]

[Number 14] a ₄ = -W _2/2

[0035]

## EQU15 ## a ₅ = −W ₂ / W ₁

[0036]

[Number 16] ^{_{a 6 = -W 2 2/2}} · W 1

Next, the calculation of the height correction calculator 17 when the welding point enters the catenary zone will be described with reference to the flowchart of FIG. First, the arithmetic unit 17 calculates S _B ,
D _B, S _A, D _A is calculated (S1). Next, the position x _{z of the} welding point is compared with the position x _s of the catenary sensor 5 in the horizontal direction. If the welding point is located before the catenary sensor 5 (S2 Yes), it is expressed by Expression 6. using catenary equation for the preceding material which are, determining the optimal height at the sensor position x _s (S3).

[0038] If the welding point exceeds Katenarisensa 5 (S2No), using a catenary equation in the row material after represented in Equation 5 to determine the optimum height at the sensor position x _s (S4).

According to this embodiment, it is possible to easily realize, by using the correction of the tension control, what could not be optimized at the time of passing the welding point by the conventional height control. Can be. Further, even when a value close to the optimal value is obtained, a plurality of simulations have conventionally been required to be performed depending on the ratio of the cross-sectional area of the preceding material and the succeeding material. However, in the embodiment, the simulation can be realized by one simulation. it can.

[0040]

As described above, according to the present invention, the catenary height at the fixed point is obtained by calculating the optimum tension set value for each welding point position with reference to the tension correction curve, and then calculating. Then, the tension correction value is calculated by comparing the measured value with the value actually measured by the sensor and the set value. As a result, what could not be optimally corrected at the time of passing the welding point by the conventional height control can be easily realized by one simulation using the correction of the tension control.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a catenary curve equation used in the embodiment.

FIG. 3 is a flowchart illustrating a processing operation of a height correction calculation unit in FIG. 1;

FIG. 4 is an explanatory diagram schematically showing a change in catenary accompanying passage of a welding point.

FIG. 5 is a graph showing a tension correction curve used for conventional tension control.

FIG. 6 is a graph showing a height correction curve used for conventional height control.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 main bridle roll 2 guide roller 3 guide roller 4 slave bridle roll 5 catenary sensor 6 speed control unit 7 motor 8 height setting unit 9 subtractor 11 height control controller 12 speed control unit 13 motor 14 droop resistance 15 height correction Circuit 16 Optimum tension setting value calculation unit 17 Height correction calculation unit 18 Subtractor 19 Adder C Catenary

Claims (1)

(57) [Claims] 1. A catenary sensor for detecting a catenary height at a fixed point of a catenary zone, a height setting device for setting an optimum value of the catenary height at a fixed point of the catenary zone by an external input, and A means for detecting a welding point position when a welding point connecting different materials having different properties enters the catenary zone, and a tension correction indicating a relationship between a welding point position prepared in advance and an optimum tension setting value for the welding point position. Means for calculating an optimum tension set value at the detected welding point position with reference to the curve; and a catenary curve for each of the preceding material forming the front catenary and the following material forming the rear catenary of the welding point in the catenary zone. Formulas include welding point location, optimal tension setting and known preceding and following material unit weight, succeeding material unit weight, catenary Means for calculating from the pan, means for calculating the catenary height at the fixed point using a corresponding catenary curve equation according to the position of the welding point with respect to the fixed point, and a catenary height optimum value set from the calculated catenary height Subtraction means for calculating a height correction amount by subtracting, and means for calculating a correction amount of tension in the front bridal roll from the height correction amount and the catenary height detected by the catenary sensor. Characteristic catenary control device.