KR101289222B1 - Method and apparatus for controlling horizontal oscillation of edgedam - Google Patents

Abstract

A method and apparatus for controlling horizontal vibration of an edge dam is disclosed. Horizontal vibration control device of the edge dam horizontal vibration control for controlling the horizontal vibration of the edge dam to follow the target horizontal distance input by applying the first storage module and the static gain stored in the first storage module and the predetermined static gain is stored A module, a distance sensor module for measuring the horizontal vibration distance of the edge dam when the horizontal vibration of the edge dam starts, an error calculation module for calculating the normalization error from the measured horizontal vibration distance and the target horizontal distance; And a second storage module for storing the normalization error calculated by the error calculation module at every sample period, wherein the horizontal vibration control module integrates the normalization error stored in the second storage module and obtains a dynamic gain from the integrated normalization error. By calculating and applying the calculated dynamic gain to control the horizontal vibration of the edge dam, the target vibration width can be accurately followed. There are technical effects.

Description

Horizontal vibration control method and device for edge dams {METHOD AND APPARATUS FOR CONTROLLING HORIZONTAL OSCILLATION OF EDGEDAM}

The present invention relates to an edge dam, by vibrating horizontally the edge dam blocking the sides of the two rolls in a twin-roll thin sheet casting apparatus, to control the horizontal vibration of the edge dam that can efficiently remove the scull generated during casting A method and apparatus are disclosed.

Generally, in the twin roll thin sheet casting process, molten steel is supplied to a space formed by a pair of casting rolls and a pair of edge dams which are being cooled, so that the height of the welding spool is kept constant, And a solidified shell formed on the surface of the casting roll is combined at a point near the casting rolls to form a cast steel, thereby continuously producing a thin plate directly from the molten steel.

1 is a perspective view showing a conventional twin roll type thin plate casting apparatus.

Referring to FIG. 1, in the continuous casting process of a thin plate, a molten steel 5 is supplied between a pair of casting rolls 1 which are cooled by water through a nozzle 2 connected to a tundish (not shown), and the casting roll 1 By rotating), a pair of solidification shells produced on the surface of the casting roll 1 are coalesced at a close point to continuously manufacture the thin plate 4.

Edge dams 3a and 3b made of refractory are provided at both side portions of the casting roll 1 to prevent the outflow of the molten steel 5 and to limit the thin plate 4 to a constant width. The supplied molten steel 5 forms the molten steel pool by the casting roll 1 and the edge dams 3a and 3b to maintain the hot water surface at a constant height. At this time, the edge dams 3a and 3b closely contact the side surfaces of the casting roll to prevent penetration of molten steel between the side surfaces of the casting roll 1 and the edge dams 3a and 3b.

According to the casting situation of the twin-roll type sheet casting process, a skull may be generated due to a drop in temperature of the molten steel. If the generated skull is mixed between the side of the casting roll 1 and the edge dams 3a and 3b, Damage to the edge dams 3a and 3b, as well as the edge quality of the slab is deteriorated, causing a serious problem that the productability of the thin plate is reduced.

The present invention has been made to solve the above problems, and to provide a method and apparatus for vibrating the edge dam horizontally to prevent the mixing of the skull that can cause the quality of the sheet and even down the casting.

In addition, the present invention is to provide a method and apparatus that can provide a dynamic gain that can be adapted to the vibration frequency and vibration width of the edge dam.

The first technical aspect of the present invention for solving the above problems of the present invention,

A first storage module storing preset static gains;

A horizontal vibration control module configured to control horizontal vibration of an edge dam so as to follow an input target horizontal distance by applying the static gain stored in the first storage module;

A distance sensor module for measuring the horizontal vibration distance of the edge dam at every sample period when the horizontal vibration of the edge dam starts;

An error calculation module for calculating a normalization error from the measured horizontal vibration distance and the target horizontal distance; And

A second storage module for storing the normalization error calculated by the error calculation module every sample period,

The horizontal vibration control module integrates the normalization error stored in the second storage module, calculates a dynamic gain from the integrated normalization error, and applies the calculated dynamic gain to control the horizontal vibration of the edge dam. To provide a horizontal vibration control device.

According to an embodiment of the present invention, the static gain is

The horizontal vibration frequency of the edge dam may be stored.

According to an embodiment of the present invention, the normalization error is represented by the following equation:

En = (Sr-Sm) / Sr

Calculated by En, En may be a normalization error, Sr may be a target horizontal vibration distance, and Sm may be a measured horizontal vibration distance.

In addition, according to an embodiment of the present invention, the dynamic gain includes a dynamic proportional gain and a dynamic integrated gain,

The dynamic proportional gain is represented by the following equation:

Computed by Gdp = (1-Etn) × Gsp,

The dynamic integration gain is represented by the following equation:

Computed by Gdi = (1-Etn) x Gsi, where Gdp is a dynamic proportional gain, Gdi is a dynamic integral gain, Gsp is a static proportional gain, and Gsi is a static integral gain. Etn may be a value obtained by integrating a normalization error stored in each sample period.

In addition, according to an embodiment of the present invention, the second storage module,

By storing the normalization error by a preset number in a first in first out (FIFO) manner, the normalization error of the preset number may be discarded.

The second technical aspect of the present invention for solving the problems of the present invention,

Controlling horizontal vibration of the edge dam so as to follow the input target horizontal distance by applying a preset static gain;

When the horizontal vibration of the edge dam starts, measuring the horizontal vibration distance of the edge dam at every sample period;

Calculating a normalization error from the measured horizontal vibration distance and the target horizontal distance, and storing the normalization error every sample period;

Integrating the stored normalization error for each sample period and calculating a dynamic gain from the integrated normalization error; And

The horizontal vibration control method of the edge dam including the step of controlling the horizontal vibration of the edge dam by applying the calculated dynamic gain.

Moreover, according to embodiment of this invention, the said predetermined static gain is

It may be stored for each horizontal vibration frequency of the edge dam.

In addition, according to an embodiment of the present invention, the normalization error is represented by the following equation:

En = (Sr-Sm) / Sr

Calculated by En, En may be a normalization error, Sr may be a target horizontal vibration distance, and Sm may be a measured horizontal vibration distance.

In addition, according to an embodiment of the present invention, the dynamic gain includes a dynamic proportional gain and a dynamic integrated gain,

The dynamic proportional gain is represented by the following equation:

Computed by Gdp = (1-Etn) × Gsp,

The dynamic integration gain is represented by the following equation:

Calculated by Gdi = (1-Etn) × Gsi, where Gdp is a dynamic proportional gain, Gdi is a dynamic integral gain, Gsp is a static proportional gain, Gsi is a static integral gain, and Etn is stored every sample period. It may be a value obtained by integrating the normalization error.

In addition, according to an embodiment of the present invention, the storing of each sample period may include:

By storing the normalization error by a preset number in a first in first out (FIFO) manner, the normalization error of the preset number may be discarded.

According to one embodiment of the present invention, by vibrating the edge dam horizontally, there is a technical effect that can prevent the mixing of the skull, which can cause degradation of the quality of the thin plate and even stopping the casting.

Further, according to another embodiment of the present invention, there is a technical effect of accurately following the target vibration width by providing a dynamic gain that can be adapted even if the vibration frequency and vibration width of the edge dam are changed.

1 is a perspective view showing a general twin roll type thin sheet casting apparatus.
2 is a block diagram of a horizontal vibration control device of the edge dam in the twin-roll thin plate casting apparatus according to an embodiment of the present invention.
3 is a view showing a first storage module according to an embodiment of the present invention.
4 illustrates a second storage module according to an embodiment of the present invention.
5 is a flowchart illustrating a horizontal vibration control method of an edge dam in a twin roll sheet metal casting apparatus according to an embodiment of the present invention.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art. Accordingly, it should be noted that the shapes, sizes, etc. of the components shown in the drawings may be exaggerated for clarity.

2 is a block diagram of a horizontal vibration control device of the edge dam in the twin-roll thin plate casting apparatus according to an embodiment of the present invention, Figure 3 is a view showing a first storage module according to an embodiment of the present invention, Figure 4 Is a view showing a second storage module according to an embodiment of the present invention.

2, the horizontal vibration control apparatus of the edge dam according to an embodiment of the present invention, the first storage module 200 and the static gain stored in the first storage module 200, the preset static gain is stored It applies to control the horizontal vibration of the edge dam (3a) to follow the input target horizontal distance (Sr), integrate the normalization error (En) stored in the second storage module 204, the dynamic gain from the integrated normalization error And a horizontal vibration control module 201 for controlling the horizontal vibration of the edge dam 3a by applying the calculated dynamic gain, and when the horizontal vibration of the edge dam 3a starts, The distance sensor module 202 for measuring the horizontal vibration distance Sm of 3a), and the error calculation module 203 for calculating the normalization error En from the measured horizontal vibration distance Sm and the target horizontal distance Sr. And the normalization error En calculated by the error calculating module 203 for each sample. The second storage module 204 may be stored for each period.

The first storage module 200 is a module for storing a predetermined static gain. Specifically, as shown in FIG. 3, the first storage module 200 stores a preset gain for each frequency in advance. For example, a gain of 0.00014 for a frequency of 1 Hz and a gain of 0.000145 for 2 Hz are stored. This gain can be, for example, a proportional gain or an integral gain.

The horizontal vibration control module 201 controls the cylinder 201a of the edge dam 3a by referring to the static gain stored in the first storage module 200 so as to follow the input target horizontal distance Sr. The horizontal vibration of 3a is controlled. Thereafter, the normalization error En stored in the second storage module 204 is integrated, and a dynamic gain is calculated from the integrated normalization error Etn according to Equation 1 below. Here, 'integrating the normalization error' means adding all of the n normalization errors En stored in the second storage module 204 to be described later. On the other hand, the dynamic gain may be a dynamic proportional (P) gain or a dynamic integral (I) gain.

[Equation 1]

Gdp = (1-Etn) × Gsp, Gdi = (1-Etn) × Gsi

Where Gdp is the dynamic proportional gain, Gdi is the dynamic integral gain, Gsp is the static proportional gain, and Gsi is the static integral gain. Etn may be a value obtained by integrating a normalization error stored in each sample period.

Thereafter, the horizontal vibration control module 201 controls the cylinder 201a of the edge dam 3a by applying the calculated dynamic gain, thereby horizontal vibration of the edge dam 3a to follow the input target horizontal distance Sr. Can be controlled. Thus, according to one embodiment of the present invention, there is a technical effect of accurately following the target vibration width by providing a dynamic gain that can be adapted even if the vibration frequency and the vibration width of the edge dam are changed.

Meanwhile, when the horizontal vibration of the edge dam 3a starts, the distance sensor module 202 measures the horizontal vibration distance Sm of the edge dam 3a every sample period, and measures the measured horizontal vibration distance Sm. It may be passed to the error calculation module 203.

The error calculating module 203 is a normalization error En for every sample period according to Equation 2 below from the horizontal vibration distance Sm received from the distance sensor module 202 and the input target horizontal distance Sr. Is calculated and the calculated normalization error En is stored in the second storage module 204.

&Quot; (2) "

En = (Sr-Sm) / Sr = 1-Sm / Sr

Here, En may be a normalization error, Sr may be a target horizontal vibration distance, and Sm may be a measured horizontal vibration distance.

The second storage module 204 is a module that stores the normalization error En calculated by the error calculation module 203. Specifically, as shown in FIG. 4, data is received for each sample period (in this case, normalization error En received from the error calculation module 203 for every sample period) and stored therein. Normalization error En is stored as many as a preset number (eg, n) in a first in first out method. Therefore, when data after the preset number n is input, the old data may be discarded in sequence every sample period.

On the other hand, reference numerals FR and MR, which are not described, indicate an upper loading cylinder of the edge dam 3a, LOWER indicates a lower loading cylinder of the edge dam 3a, and DS denotes an edge dam provided at both side portions of the casting roll 1 (see FIG. 1). It means that the edge dam (3a) installed on the drive side (DS) of (3a, 3b).

In addition, although the horizontal vibration control for the DS edge dam 3a is illustrated in FIG. 2, the horizontal vibration control may be performed in the same manner for the work side (WS) edge dam 3b on the opposite side. have.

Finally, FIG. 5 is a flowchart for explaining a horizontal vibration control method of an edge dam in a twin-roll thin sheet casting apparatus according to an embodiment of the present invention.

2 to 5, first, a predetermined static gain is stored in the first storage module 200, and the horizontal vibration control module 201 stores the first storage to follow the input target horizontal distance Sr. By controlling the cylinder 201a of the edge dam 3a with reference to the static gain stored in the module 200, the horizontal vibration of the edge dam 3a is controlled (S501).

Thereafter, when the horizontal vibration of the edge dam 3a starts, the distance sensor module 202 measures the horizontal vibration distance Sm of the edge dam 3a every sample period, and measures the measured horizontal vibration distance Sm. It may be transmitted to the error calculation module 203 (S502).

Next, the error calculating module 203 is a normalization error (for each sample period) from the horizontal vibration distance Sm received from the distance sensor module 202 and the input target horizontal distance Sr according to Equation 2 below. En) is calculated and the calculated normalization error En is stored in the second storage module 204 (S503).

&Quot; (2) "

En = (Sr-Sm) / Sr = 1-Sm / Sr

Here, En may be a normalization error, Sr may be a target horizontal vibration distance, and Sm may be a measured horizontal vibration distance.

Thereafter, the horizontal vibration control module 201 integrates a normalization error En stored in the second storage module 204 and calculates a dynamic gain from the integrated normalization error Etn according to Equation 1 below. (S504). Here, 'integrating the normalization error' means adding all of the n normalization errors En stored in the second storage module 204 to be described later. On the other hand, the dynamic gain may be a dynamic proportional (P) gain or a dynamic integral (I) gain.

[Equation 1]

Gdp = (1-Etn) × Gsp, Gdi = (1-Etn) × Gsi

Where Gdp is the dynamic proportional gain, Gdi is the dynamic integral gain, Gsp is the static proportional gain, and Gsi is the static integral gain. Etn may be an integrated normalization error in which the normalization error stored in every sample period is integrated.

Finally, the horizontal vibration control module 201 controls the cylinder 201a of the edge dam 3a by applying the calculated dynamic gain, thereby horizontally following the input target horizontal distance Sr. Vibration may be controlled (S505).

As described above, according to one embodiment of the present invention, there is a technical effect of accurately following the target vibration width by providing a dynamic gain that can be adapted even if the vibration frequency and the vibration width of the edge dam are changed.

The best embodiments have been disclosed in the drawings and specification above. Although specific terms have been employed herein, they are used for purposes of illustration only and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

1: casting roll 2: nozzle
3a, 3b: edge dam 4: thin plate
5: molten steel 200: first storage module
201: horizontal vibration control module 201a: cylinder
202: distance measurement module 203: error calculation module
204: second storage module

Claims (10)

A first storage module storing preset static gains;
A horizontal vibration control module configured to control horizontal vibration of an edge dam so as to follow an input target horizontal distance by applying the static gain stored in the first storage module;
A distance sensor module for measuring the horizontal vibration distance of the edge dam at every sample period when the horizontal vibration of the edge dam starts;
An error calculation module for calculating a normalization error from the measured horizontal vibration distance and the target horizontal distance; And
A second storage module for storing the normalization error calculated by the error calculation module every sample period,
The horizontal vibration control module integrates the normalization error stored in the second storage module, calculates a dynamic gain from the integrated normalization error, and applies the calculated dynamic gain to control the horizontal vibration of the edge dam. Horizontal vibration control device.
The method of claim 1,
The static gain is,
Horizontal vibration control device of the edge dam is stored for each horizontal vibration frequency of the edge dam.
The method of claim 2,
The normalization error is represented by the following equation:
En = (Sr-Sm) / Sr
Where En is the normalization error, Sr is the target horizontal vibration distance, and Sm is the measured horizontal vibration distance.
The method of claim 3,
The dynamic gain includes a dynamic proportional gain and a dynamic integrated gain,
The dynamic proportional gain is represented by the following equation:
Computed by Gdp = (1-Etn) × Gsp,
The dynamic integration gain is represented by the following equation:
Computed by Gdi = (1-Etn) x Gsi, where Gdp is a dynamic proportional gain, Gdi is a dynamic integral gain, Gsp is a static proportional gain, and Gsi is a static integral gain. Etn is the horizontal vibration control device of the edge dam which is the value obtained by integrating the normalization error stored in every sample period.
The method of claim 1,
The second storage module,
And storing the normalization error by a preset number in a first-in-first-out (FIFO) manner, thereby canceling more than the preset number of normalization errors.
Controlling horizontal vibration of the edge dam so as to follow the input target horizontal distance by applying a preset static gain;
When the horizontal vibration of the edge dam starts, measuring the horizontal vibration distance of the edge dam at every sample period;
Calculating a normalization error from the measured horizontal vibration distance and the target horizontal distance, and storing the normalization error every sample period;
Integrating the stored normalization error for each sample period and calculating a dynamic gain from the integrated normalization error; And
And controlling the horizontal vibration of the edge dam by applying the calculated dynamic gain.
The method according to claim 6,
The preset static gain is
Horizontal vibration control method of the edge dam is stored for each horizontal vibration frequency of the edge dam.
The method of claim 7, wherein
The normalization error is represented by the following equation:
En = (Sr-Sm) / Sr
Where En is the normalization error, Sr is the target horizontal vibration distance, and Sm is the measured horizontal vibration distance.
9. The method of claim 8,
The dynamic gain includes a dynamic proportional gain and a dynamic integrated gain,
The dynamic proportional gain is represented by the following equation:
Computed by Gdp = (1-Etn) × Gsp,
The dynamic integration gain is represented by the following equation:
Computed by Gdi = (1-Etn) × Gsi, where Gdp is a dynamic proportional gain, Gdi is a dynamic integral gain, Gsp is a static proportional gain, Gsi is a static integral gain, and Etn is stored every sample period Horizontal vibration control method of edge dam which is a value obtained by integrating normalization error.
The method of claim 7, wherein
The storing of each sample period may include:
And storing the normalization error by a predetermined number in a first-in-first-out (FIFO) manner, thereby discarding more than the predetermined number of normalization errors.

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