KR20090084223A - A method and system for controlling a position of a tundish - Google Patents

Abstract

A turn-dish position controlling method and a system suitable for the same are provided to prevent vibration and noise etc. because the positional deviation is removed through the synchronizing process between a plurality of cylinders. A turn-dish position controlling method is as follows. The final target height is divided and a plurality of unit target heights is produced. The unit target height produced is outputted(620). The opening of each oil pressure valve is controlled based on the driving voltage according to the outputted unit target height as described above and the size of the fluid pressure supplied to each cylinder is controlled. Whether the difference of the unit target height exceeds the first critical value or not(650) is determined. According to the decision result, the driving voltage supplied to the oil pressure valve connected to the corresponding cylinder is changed(660).

Description

A method and system for controlling a position of a tundish}

The present invention relates to a tundish position control method and a system suitable therefor, in particular, precisely controlling the position of each cylinder that moves the tundish up and down, and ultimately by effectively eliminating the positional deviation occurring between the cylinders. The present invention relates to a tundish position control method capable of precisely controlling a moving height of a dish, and a system suitable for the same.

In general, molten steel melted in a steel mill is transferred to a continuous casting machine in a ladle. When molten steel is directly injected from a ladle into a mold, it is difficult to control injection capacity or maintain a constant casting temperature. It is placed in a tundish container, which is then rectified and injected into a mold. Here, the tundish is a facility having a function of supplying and distributing molten steel to continuously cast during ladle replacement in the playing process.

On the other hand, the tundish car for moving the tundish is attached with a position control device that can adjust the preheating position, the running position, and the casting position of the tundish differently. The conventional position control device is composed of a position sensor, a plurality of cylinders, a hydraulic shutoff valve, and a mechanical left and right parallel hydraulic circuit, and a hydraulic shutoff valve connected to a plurality of cylinders based on one position signal acquired by the control system. By adjusting the opening degree of the tundish lifting or lowering height is made.

However, when uniformly adjusting the opening degree of the hydraulic shutoff valve through the position signal generated from one position sensor, not only the position control of individual cylinders is possible but also the synchronous position control of a plurality of cylinders is impossible. This can cause serious problems in that it is difficult to maintain the same profile for each cylinder to reach the target position even when the same hydraulic pressure is applied to each cylinder due to the unbalance of the cylinder or the tundish.

In addition, the conventional position control device uses a method of performing consistent PID control until the final target position is reached, which increases the possibility of height deviation of the cylinders due to overshooting that may occur during the control, and sudden output fluctuations. And increase the likelihood of causing vibration due to the change of direction. In addition, when a height deviation occurs in the cylinders due to the manual operation of the user, there is a problem that can not be automatically removed and must be roughly parallel again manually.

The technical problem to be solved by the present invention is a tundish capable of precisely controlling the position of each cylinder step by step using an automatic driving controller and a plurality of position sensors and to effectively eliminate the positional deviation between different cylinders. It is to provide a position control method and a system suitable for the same.

The tundish position control method according to an embodiment of the present invention for solving the technical problem, generates a plurality of unit target height by dividing the final target height, and outputs the generated unit target height at regular time intervals Adjusting the hydraulic pressure supplied to each cylinder by adjusting the opening degree of each hydraulic valve based on the output voltage according to the output unit target height, and the current measured height of each cylinder and the current target height of each cylinder. Determining whether the difference exceeds the first threshold value, and changing the driving voltage supplied to the hydraulic valve connected to the corresponding cylinder according to the determination result.

Preferably, the step of changing the drive voltage, it is determined whether the difference in the current measured height of each cylinder exceeds the second threshold value, and according to the determination result is a drive voltage supplied to the hydraulic valve connected to at least one cylinder Re-changing to remove the positional deviation existing between each cylinder.

Preferably, the step of changing the drive voltage, it is determined whether the difference in the current measurement height of each cylinder exceeds the third threshold, and the drive voltage supplied to the hydraulic valve connected to the at least one cylinder according to the determination result Suspending to further eliminate the positional deviation existing between each cylinder.

Preferably, the step of changing the driving voltage, the position deviation existing between each cylinder by increasing or decreasing the driving voltage supplied to the hydraulic valve corresponding to the cylinder having a relatively faster movement speed of the plurality of cylinders Removing the step.

Preferably, the step of changing the drive voltage, it is determined whether the difference in the current measurement height of each cylinder exceeds the third threshold, and according to the determination result the drive voltage supplied to the hydraulic valve connected to at least one cylinder Suspending to remove the initial positional deviation of each cylinder.

In the tundish position control method according to another embodiment of the present invention for solving the above technical problem, the target arrival height of each cylinder and the actual measured height is compared at predetermined time intervals, the height difference is greater than the first threshold value Generating a logic signal to the controller; and adjusting a magnitude of the hydraulic pressure supplied to each cylinder in response to the logic signal.

Advantageously, said tundish position control method comprises: comparing the actual measured height of each cylinder at predetermined time intervals, generating a logic signal when the height difference is greater than or equal to a second threshold, and responding to said logic signal; And resizing the hydraulic pressure supplied to the at least one cylinder.

The tundish position control system according to an embodiment of the present invention for solving the technical problem,

A plurality of cylinders operating according to the supplied hydraulic pressure, a plurality of hydraulic valves for adjusting the hydraulic pressure supplied to the corresponding cylinder, a plurality of position sensors for measuring the current position of the corresponding cylinder, and inputs from the position sensors It characterized in that it comprises an automatic running controller for stepwise controlling the operation of each cylinder based on the current position of each cylinder.

Preferably, the automatic driving controller generates a driving voltage according to the unit target height obtained by dividing the final target height at regular distance intervals, and applies the driving voltage to each hydraulic valve, and the unit target height for each cylinder at regular time intervals. And the actual measured height, and if the height difference exceeds the first threshold, adjust the size of the hydraulic pressure supplied to the cylinder.

Preferably, the automatic running controller compares the actual measured height of each cylinder at regular time intervals, and if the height difference exceeds the second threshold, readjusts the magnitude of the hydraulic pressure supplied to the at least one cylinder. do.

The tundish position control system according to another embodiment of the present invention for solving the technical problem, a plurality of electric motors operating in accordance with the supplied electricity, a plurality of speed controller for controlling the electricity supplied to the corresponding electric motor For example, a plurality of position sensors measuring a current position of a corresponding electric motor, and an automatic driving controller for stepwise controlling the operation of each electric motor based on the current position of each electric motor input from the position sensors. Characterized in that it comprises a.

Due to the configuration as described above, the tundish position control method according to the present invention can not only accurately perform the position control of individual cylinders step by step, but also dynamic synchronization and static synchronization when a position deviation occurs between a plurality of cylinders. By removing this through the process, it is possible to prevent vibration and noise, and to increase mechanical durability and secure stability of automatic operation.

In order to fully understand the present invention, the operational advantages of the present invention, and the objects attained by the practice of the present invention, reference should be made to the accompanying drawings which illustrate preferred embodiments of the present invention and the contents described in the drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In describing the present invention, if it is determined that the detailed description of the related well-known configuration or function may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

1 is a block diagram illustrating a tundish position control system according to an exemplary embodiment.

Referring to FIG. 1, the tundish position control system 100 according to the present invention includes an upper remote controller 110, an automatic driving controller 120, a first hydraulic valve 130, a first cylinder 140, and a first cylinder 140. The first position sensor 150, the second hydraulic valve 160, the second cylinder 170, the second position sensor 180, and the hydraulic station 190 are included. Hereinafter, these components will be described in detail.

The upper remote controller 110 is a Human Machine Interface (HMI) system that receives and displays processing data from the automatic driving controller 120 through a communication protocol and provides an interface for the operator to control the processing. In particular, the upper remote controller 110 displays the set height data, the measured height data, the driving voltage, and the state, which are the data processed by the automatic driving controller 120, to the operator, and the operating environment setting, the monitoring screen edit, and the data. Can perform functions such as collection.

The automatic driving controller 120 applies a driving voltage of a predetermined magnitude to the first hydraulic valve 130 and the second hydraulic valve 160 to adjust the opening degree of the hydraulic valves 130 and 160, and the first position sensor 150. And receiving a cylinder position signal from the second position sensor 180 to determine current heights of the first cylinder 140 and the second cylinder 170. The automatic driving controller 120 is configured as a proportional controller and generates a drive voltage changed according to the difference between the unit target height and the current measurement height, and outputs the driving voltage to the first hydraulic valve 130 and the second hydraulic valve 160.

The first hydraulic valve 130 and the second hydraulic valve 160 may be hydraulic proportional valves that operate according to a driving voltage input from the automatic driving controller 120. In particular, the first hydraulic valve 130 and the second hydraulic valve 160 supply or block the hydraulic pressure supplied from the hydraulic station 190 to the first cylinder 140 and the second cylinder 170 according to the driving voltage. . The first cylinder 140 and the second cylinder 170 are raised or lowered according to the moving direction of the first hydraulic valve 130 and the second hydraulic valve 160.

The first position sensor 150 and the second position sensor 180 detect the current heights of the first cylinder 140 and the second cylinder 170 in real time, and automatically output a position signal indicating the detected height. 120). Hydraulic station 190 is composed of a hydraulic tank and a hydraulic valve, it may be a device for supplying a hydraulic pressure having a pressure of 250Bar. Meanwhile, in FIG. 1, the height is controlled by using two cylinders, but the number of the hydraulic valve and the position sensor may vary according to the number of cylinders used.

2 is a block diagram illustrating an automatic driving controller according to an embodiment of the present invention.

2, the automatic driving controller 200 according to the present invention includes a first setpoint adjuster 210, a first comparator 220, a first position controller 230, a first voltage generator 240, and a first A second setpoint regulator 250, a second comparator 260, a second position controller 270, and a second voltage generator 280. Hereinafter, these components will be described in detail.

The first setpoint adjuster 210 divides the set final target height at predetermined distance intervals, and increases or decreases the unit target height divided at each predetermined time interval and outputs the divided target height. For example, if the final target height is 760 mm, the unit target height is 5 mm, 10 mm,... Outputs 755mm and 760mm in order. Meanwhile, the first setpoint adjuster 210 may further subdivide the division interval immediately before reaching the final target height so that overshooting does not occur when the final target height is reached.

The first comparator 220 determines whether a difference between the unit target height input from the first setpoint adjuster 210 and the current measurement height input from the first position sensor is greater than or equal to the first threshold value, and determines a logic signal according to the determination result. Output For example, assuming that the estimated time for a cylinder to move 5 mm is 0.5 seconds when the hydraulic valve is opened at 50%, the cylinder may actually move only 3 mm due to internal or external factors. The first comparator 220 detects whether the delay operation is performed.

The first position controller 230 generates and outputs a control signal according to the unit target height input from the first setpoint adjuster 210. For example, when the input unit target height approaches the final target height, a control signal is generated to reduce the magnitude of the driving voltage. In addition, the first position controller 230 changes and outputs the control signal being output according to the logic signal input from the first comparator 220. For example, when a logic signal is input from the first comparator 220, a control signal for reducing the magnitude of the driving voltage is output.

The first voltage generator 240 generates and outputs a driving voltage according to a control signal input from the first position controller 230. The driving voltage may be -10V to 10V. When the driving voltage is 0V to 10V, the hydraulic valve is opened in the first direction to raise the cylinder rod, and when the driving voltage is -10V to 0V, the hydraulic valve is in the second direction. Open and the cylinder rod of the cylinder lowers. That is, whether the cylinder rises or falls and the rise / fall speed is determined according to the driving voltage.

Similar to the first setpoint adjuster 250, the second setpoint adjuster 250 divides the set final target height at predetermined distance intervals, and increases or decreases the unit target height divided at every predetermined time interval and outputs the divided target height. That is, the first setpoint adjuster 210 and the second setpoint adjuster 250 respectively divide the set final target height into a plurality of unit target heights. On the other hand, since the cylinder may be raised or lowered, the final target height may have a large value or a small value based on the current measurement height.

Similar to the first comparator 220, the second comparator 260 may determine whether a difference between the unit target height input from the second setpoint adjuster 250 and the current measurement height fed back from the second position sensor is greater than or equal to the first threshold. And outputs a logic signal according to the determination result. The first comparator 220 and the second comparator 260 perform a comparison operation at intervals of an estimated time (for example, 0.5 seconds) normally required for each cylinder to move a predetermined distance (for example, 5 mm). Outputs a logic signal according to the result.

Similar to the first position controller 230, the second position controller 270 generates and outputs a control signal according to the unit target height input from the second setpoint adjuster 250. For example, when the input unit target height is the initial unit target height, a control signal is generated to increase the magnitude of the driving voltage. In addition, the second position controller 270 changes and outputs the control signal being output according to the logic signal output from the first comparator 220. If the logic signal is not input, the existing control signal is maintained.

Similar to the first voltage generator 240, the second voltage generator 280 generates and outputs a driving voltage according to a control signal input from the second position controller 270. As described above, whether the cylinder rises or falls and the rise / fall speed is determined according to the driving voltage. Although not shown in FIG. 1, the tundish position control system 100 according to the present invention may further include a lock valve to block the flow path and maintain the current position when the cylinder reaches the final target height.

Meanwhile, although FIG. 2 illustrates a plurality of functional blocks for independently controlling two cylinders, the number of functional blocks may vary according to the number of cylinders used to control the height of the tundish. For example, in order to operate one cylinder, a set value first regulator 210, a first comparator 220, a first position controller 230, and a first voltage generator 240 are required. In order to operate, four blocks each having the same function are required.

3 is a block diagram illustrating an automatic driving controller according to another embodiment of the present invention.

Referring to FIG. 3, the automatic driving controller 300 according to the present invention includes a first setpoint adjuster 310, a first comparator 320, a first position controller 330, a first voltage generator 340, and a first A second setpoint adjuster 350, a second comparator 360, a second position controller 370, a second voltage generator 380, and a third comparator 390. Hereinafter, these components will be described in detail based on differences from the blocks shown in FIG. 2.

The third comparator 390 is a first measuring height of the first cylinder 140 input from the first position sensor 150 shown in FIG. 1 and a second cylinder input from the second position sensor 180 during automatic driving. It is determined whether the difference in the second measurement height of 170 is greater than or equal to the second threshold value, and the logic signal according to the determination result is output to the first position controller 330 or the second position controller 380. For this reason, it is possible to control so that the height deviation which arises when a 1st cylinder and a 2nd cylinder raises or lowers simultaneously can be automatically removed in real time.

On the other hand, decelerating the speed of a cylinder with a fast moving speed is more efficient than accelerating the speed of a cylinder with a slow moving speed. Therefore, in the operation of controlling the lifting of the tundish, when the measuring height of the first cylinder is a and the measuring height of the second cylinder is b (b <a) at a specific time, the hydraulic valve corresponding to the first cylinder It is preferable to keep the moving speed of the first cylinder and the second cylinder the same by controlling the magnitude of the driving voltage for controlling the operation to decrease.

The first position controller 330 or the second position controller 370 outputs a control signal output to the first voltage generator 340 or the second voltage generator 380 according to a logic signal input from the third comparator 390. Change it and print it out. For example, the first position controller 330 outputs a control signal to the first voltage generator 340 to generate a driving voltage lower than the current driving voltage in response to a logic signal input from the third comparator 390. do. The logic signal is preferably a 2-bit logic signal capable of displaying four logic states.

On the other hand, the automatic driving controller 300 according to the present invention can be applied to a four cylinder position control system. In that case, the third comparator 390 detects the maximum height and the minimum height by comparing the current measurement height of each cylinder input from four different position sensors, and then determines whether the difference is greater than or equal to the second threshold. In addition, dynamic synchronization of the cylinder may be performed by outputting a logic signal according to the determination result to a position controller corresponding to the maximum measurement height or a position controller corresponding to the minimum measurement height.

4 is a block diagram illustrating an automatic driving controller according to another embodiment of the present invention.

Referring to FIG. 4, the automatic driving controller 400 according to the present invention includes a first setpoint adjuster 410, a first comparator 420, a first position controller 430, a first voltage generator 440, And a second setpoint adjuster 450, a second comparator 460, a second position controller 470, a second voltage generator 480, and a third comparator 490. Hereinafter, these components will be described in detail based on differences from the blocks shown in FIG. 2.

The third comparator 490 measures the height of the first cylinder 140 input from the first position sensor 150 shown in FIG. 1 and the measurement of the second cylinder 170 input from the second position sensor 180. It is determined whether the difference in height is greater than or equal to the third threshold value, and a logic signal according to the determination result is output to the first setpoint adjuster 410 or the second setpoint adjuster 450. As a result, the height deviation caused by the manual operation can be eliminated before the automatic driving, and even if the deviation is large during the driving, the static synchronization of the cylinder can be performed.

Even if the deviation caused by the plurality of cylinders lifting and lowering at the same time is automatically removed, the internal movement of the specific cylinder may cause the continuous moving speed delay. Therefore, for efficiency, it is desirable to suspend the operation of a cylinder with a fast moving speed, wait until the cylinder with a slow moving speed reaches a predetermined divided set height, and then raise or lower a plurality of cylinders simultaneously when the same position is reached. .

In addition, when the driver manually operates the driving of the plurality of cylinders, the height deviation may be large due to the load unbalance applied to the cylinders. Therefore, when the driver sets a predetermined set value to the final target height in order to perform the automatic driving, it is preferable to remove the height deviation existing between the cylinders in advance and then raise or lower the cylinder. To this end, the third comparator 490 outputs a logic signal according to the case where the measured height difference between the cylinders is large before or during operation.

The first setpoint adjuster 410 or the second setpoint adjuster 450 does not output a unit target height in a section in which a logic signal is input so that the first position controller 430 does not generate a control signal for generating a driving voltage. Don't let that happen. Meanwhile, the first setpoint adjuster 410 or the second setpoint adjuster 450 outputs a unit target height in a section in which no logic signal is input, thereby generating a control signal for the first position controller 430 to generate a driving voltage. Let's do it. That is, automatic driving is performed only when the height deviation is removed.

5 is a block diagram illustrating a tundish position control system according to another embodiment of the present invention.

Referring to FIG. 5, the tundish position control system 500 according to the present invention includes an upper remote controller 510, an automatic driving controller 520, a first speed controller 530, a first electric motor 540, A first position sensor 550, a second speed controller 560, a second electric motor 570, and a second position sensor 580. Hereinafter, these components will be described in detail based on differences from the blocks illustrated in FIG. 1.

The automatic driving controller 520 adjusts the control amount of the speed controllers 530 and 540 by applying a predetermined driving voltage to the first speed controller 530 and the second speed controller 560, and the first position sensor 550 and The motor position signal is input from the second position sensor 580 to determine the heights of the first electric motor 540 and the second electric motor 570. In particular, the automatic driving controller 520 is configured as a proportional controller and generates a driving voltage corresponding to the difference between the set height and the measured height and outputs the driving voltage to the first speed controller 530 and the second speed controller 560.

The first speed controller 530 and the second speed controller 560 operate according to a driving voltage input from the automatic driving controller 520, and each of the first electric motor 540 receives electricity input from the electric station 590. And the second electric motor 570 or the second electric motor 570 can perform precise position control and synchronous control of the first electric motor 540 and the second electric motor 570. Although only two electric motors are shown in FIG. 5, four or more electric motors may be used to control the height of the tundish.

6 is a detailed flowchart illustrating a tundish position control method according to an embodiment of the present invention.

The set final target height is divided into a plurality of unit target heights (610). For example, if the current height is 800mm and the final target height is 40mm, it is divided into 10mm units and the unit target height is 790mm, 780mm,... Produces 50mm and 40mm. The unit target height is increased or decreased according to the tundish moving direction and outputted (620). Specifically, in the tundish raising and lowering operation, the unit target height is increased in stages and output, and in the tundish lowering operation, the unit target height is decreased in stages and output.

A predetermined driving voltage corresponding to the output unit target height is applied to the hydraulic valve (630). The cylinder rises when the drive voltage is positive and drops when the drive voltage is negative. In addition, the larger the absolute value of the driving voltage, the larger the opening degree of the hydraulic valve, the higher the moving speed of the cylinder, the smaller the absolute value of the driving voltage, the smaller the opening degree of the hydraulic valve, the lower the moving speed of the cylinder. When the 0 V driving voltage, which is the neutral position signal, is applied to the hydraulic valve, the movement of the cylinder is stopped.

The current measurement height of the cylinder measured using the position sensor is input every predetermined time, and the output unit target height and the input current measurement height are compared (640). The predetermined time is preferably shorter than the time normally required to reach the current unit target height from the previous unit target height. It is determined whether the difference between the unit target height and the current measurement height exceeds the first threshold (650). The first threshold is preferably within ± 1 mm, but may vary depending on the purpose of varying the position of the tundish.

As a result of the determination, when the first threshold value is exceeded, the opening degree is adjusted by changing a driving voltage currently being applied to the hydraulic valve (660). Specifically, the absolute value of the driving voltage is increased when the unit target height is relatively large, and the absolute value of the driving voltage is decreased when the current measurement height is relatively large. As a result of the determination, if the first threshold value is not exceeded, it is determined whether the unit target height has reached the final target height. If it is determined that the final target height is not reached, the unit target height is increased / decreased (620).

As a result of determination, when the final target height is reached, the neutral position signal (0V) is applied to the hydraulic valve, and the lock solenoid valve is operated to block the flow path of the cylinder to maintain the current position (680). In the tundish position control method according to the present invention, as described above, the unit target height is output at predetermined time intervals to control the movement speed of the cylinder in stages, and the movement of the cylinder when a certain difference occurs between the actual height and the expected height. The speed can be precisely controlled step by step.

7 is a detailed flowchart illustrating a tundish position control method according to another embodiment of the present invention.

The set final target height is divided into a plurality of unit target heights (710). The divided plurality of unit target heights may have different distance intervals. The generated unit target height is increased or decreased according to whether the cylinder is raised or lowered (720). A driving voltage for adjusting the opening degree of the hydraulic proportional valve corresponding to the output unit target height is generated and output (operation 730). The magnitude of the driving voltage is preferably -10V to + 10V.

Each unit time is compared with the output unit target height and the actual measured height of each cylinder (740). It is determined whether the difference between the unit target height and the actual measurement height exceeds a first threshold (750). As a result of the determination, when the first threshold is exceeded, the cylinder determines that the movement profile is abnormal to increase or decrease the magnitude of the driving voltage currently being output. As a result of the determination, when the first threshold is not exceeded, the actual measurement heights of the respective cylinders input from the respective position sensors are compared with each other (770).

It is determined whether the difference in the actual measurement height exceeds the second threshold (780). If it is determined that the second threshold is exceeded, the current driving voltage output to any one hydraulic valve is changed (760). For example, during the elevating operation, the magnitude of the current driving voltage output to the hydraulic valve attached to the cylinder having the high speed of movement is reduced. If it is determined that the second threshold is not exceeded, it is determined whether the final target height is reached (790). As a result of determination, when the final target height is not reached, the unit target height currently being output is increased or decreased to output.

As a result of determination, when the final target height is reached, the neutral position signal (0V) is applied to the hydraulic valve, and the lock solenoid valve is operated to block the flow path of the cylinder to maintain the current position (780). The tundish position control method according to the present invention, as described above, when a position deviation occurs between each cylinder moving toward the same unit target height, by slowing the moving speed of the fast moving cylinder between the cylinders This has the effect of doing a static synchronization.

8 is a detailed flowchart illustrating a tundish position control method according to another embodiment of the present invention.

The set final target height is divided into a plurality of unit target heights (805). Since the positions of all the cylinders must be parallel, the final target height applies equally for each cylinder. The generated unit target height is increased / decreased according to the advancing direction of the cylinder (810). For example, if the current position is 40mm, the target height is 760mm, and divided into 5mm units, the initial unit target height is 45mm. In operation 815, a predetermined driving voltage according to the output unit target height is applied to the hydraulic valve.

When the predetermined time passes, the output unit target height is compared with the actual measured height (820). The predetermined time represents an expected time normally required for the cylinder to reach the unit target height when a constant driving voltage is applied to the hydraulic valve. In operation 825, it is determined whether a difference between the unit target height and the actual measurement height exceeds a first threshold. As a result of the determination, when the first threshold is exceeded, a magnitude of the driving voltage currently being output is increased or decreased to output the result (830). This applies for each cylinder.

As a result of the determination, when the first threshold value is not exceeded, the first measurement height of the first cylinder and the second measurement height of the second cylinder are compared (835). Here, the number of cylinders is not limited to two. It is determined whether the difference between the first current measurement height and the second current measurement height exceeds the second threshold (840). As a result of the determination, if the second threshold is exceeded, it is determined whether the third threshold is exceeded (850). As a result of determination, when the third threshold value is not exceeded, an absolute value of the driving voltage applied to the cylinder having a relatively fast moving speed is reduced (830).

As a result of the determination, when the third threshold is exceeded, the driving voltage applied to the rapidly moving cylinder is temporarily suspended (855). Thereafter, it is again determined whether the second threshold is exceeded (840). Preferably, the third threshold is greater than the second threshold. In other words, if the positional deviation of the cylinder is directly correctable during autonomous driving, synchronization is realized by changing the driving voltage currently output. However, if the cylinder is not directly correctable during autonomous driving, the movement of the rapidly moving cylinder is temporarily suspended. Synchronization is achieved.

If it is determined that the second threshold is not exceeded, it is determined whether the unit target height currently being output has reached the final target height (845). If it is determined that the final height is not reached, the unit target height currently being output is increased / decreased (810). As a result of determination, when the final height is reached, the locking valve is operated to fix the position of the cylinder. As described above, the tundish position control method according to the present invention can realize static synchronization by stopping the operation of a cylinder that is rapidly moving during operation.

9 is a diagram illustrating a relationship between data used in a tundish position control system according to the present invention.

9, the left and right set values indicating the change in the unit target height of the first cylinder and the second cylinder, the left and right measured values indicating the change in the present measurement height of the first cylinder and the second cylinder, the first cylinder and the second cylinder Left and right operation values indicating changes in driving voltages applied to the attached hydraulic valves are shown. Here, the vertical axis represents height and the horizontal axis represents time, and FIG. 9 shows a process of changing at least an operating value so that the left and right measurement values linearly follow the left and right set values.

Meanwhile, the present invention can be embodied as computer readable codes on a computer readable recording medium. Computer-readable recording media include all kinds of recording devices, such as ROMs, RAMs, CD-ROMs, magnetic tapes, floppy disks, and optical disks, on which data that can be read by a computer system are stored. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

The best embodiment has been disclosed in the drawings and specification. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not used to limit the scope of the present invention as defined in the meaning or claims.

Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

1 is a block diagram illustrating a tundish position control system according to an exemplary embodiment.

2 is a block diagram illustrating an automatic driving controller according to an embodiment of the present invention.

3 is a block diagram illustrating an automatic driving controller according to another embodiment of the present invention.

4 is a block diagram illustrating an automatic driving controller according to another embodiment of the present invention.

5 is a block diagram illustrating a tundish position control system according to another embodiment of the present invention.

6 is a detailed flowchart illustrating a tundish position control method according to an embodiment of the present invention.

7 is a detailed flowchart illustrating a tundish position control method according to another embodiment of the present invention.

8 is a detailed flowchart illustrating a tundish position control method according to another embodiment of the present invention.

9 is a diagram illustrating a relationship between data used in a tundish position control system according to the present invention.

Claims (12)

Dividing a final target height to generate a plurality of unit target heights, and increasing or decreasing the generated unit target heights at regular time intervals; Adjusting the amount of oil pressure supplied to each cylinder by adjusting the opening degree of each hydraulic valve based on the output driving voltage according to the unit target height; And Determining whether the difference between the current measurement height of each cylinder and the current unit target height exceeds a first threshold value, and changing the driving voltage supplied to the hydraulic valve connected to the corresponding cylinder according to the determination result. How to control tundish position. The method of claim 1, wherein the changing of the driving voltage comprises: It is determined whether the difference in the current measured height of each cylinder exceeds the second threshold, and according to the determination result, the drive voltage supplied to the hydraulic valve connected to the at least one cylinder is changed to determine the positional deviation existing between each cylinder. The method of controlling a tundish position further comprising the step of removing. The method of claim 2, wherein the changing of the driving voltage comprises: It is determined whether the difference in the current measured height of each cylinder exceeds the third threshold, and according to the determination result, the driving voltage supplied to the hydraulic valve connected to the at least one cylinder is stopped to determine the positional deviation existing between each cylinder. The method of controlling a tundish position further comprising the step of removing. The method of claim 3, wherein changing the driving voltage comprises: A tundish comprising: increasing or decreasing a driving voltage supplied to a hydraulic valve corresponding to a cylinder having a relatively faster moving speed among the plurality of cylinders to eliminate a positional deviation existing between each cylinder. Position control method. The method of claim 2, wherein the changing of the driving voltage comprises: It is determined whether the difference in the current measurement height of each cylinder exceeds the third threshold, and according to the determination result, the driving voltage supplied to the hydraulic valve connected to the at least one cylinder is stopped to remove the initial position deviation of each cylinder. Tundish position control method comprising the step of. Comparing the target arrival height of each cylinder with the actual measured height at predetermined time intervals, and generating a first logic signal when the height difference is greater than or equal to the first threshold; And And adjusting the magnitude of the hydraulic pressure supplied to each cylinder by changing the driving voltage supplied to the hydraulic valve in response to the first logic signal. According to claim 6, The tundish position control method, Comparing the actual measured height of each cylinder at predetermined time intervals and generating a second logic signal if the height difference is greater than or equal to a second threshold; And And resizing the oil pressure supplied to the at least one cylinder in response to the second logic signal. A plurality of cylinders operating according to the hydraulic pressure supplied; A plurality of hydraulic valves for adjusting the hydraulic pressure supplied to the corresponding cylinder; A plurality of position sensors measuring the current position of the corresponding cylinder; And A tundish position control system comprising an automatic running controller for adjusting the amount of hydraulic pressure supplied to each cylinder based on the current position of each cylinder input from the position sensors. The method of claim 8, wherein the automatic driving controller, A tundish characterized by comparing the unit target height and the actual measured height for each cylinder at regular time intervals, and if the height difference exceeds the first threshold, resizing the hydraulic pressure supplied to the cylinder. Position control system. The method of claim 9, wherein the automatic driving controller, A tundish position control system for comparing the actual measured height of each cylinder at regular time intervals and resizing the hydraulic pressure supplied to the at least one cylinder when the height difference exceeds the second threshold. . A plurality of electric motors operating in accordance with electricity supplied; A plurality of speed controllers for regulating the electricity supplied to the corresponding electric motors; A plurality of position sensors measuring a current position of a corresponding electric motor; And A tundish position control system comprising an automatic running controller for adjusting the amount of electricity supplied to each electric motor based on the current position of each electric motor input from the position sensors. A computer-readable recording medium having recorded thereon a computer code for implementing the method of claim 1.

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