Invention title: Continuous casting control device, method and program
Technical field
[0001]
　The present invention relates to a control device, method and program for continuous casting.
　The present application claims priority based on Japanese Patent Application No. 2018-17409 filed in Japan on September 18, 2018, the contents of which are incorporated herein by reference.
Background technology
[0002]
　In continuous steel casting, it is important to suppress fluctuations in the molten steel level in the mold and keep the molten metal level constant, in addition to preventing deterioration of slab quality, from the viewpoint of stabilizing operations. Usually, feedback control is performed so as to keep the molten metal level constant based on the measured value of one molten metal level measuring meter.
[0003]
　As a technique of this type, for example, Patent Document 1 discloses a method for controlling a water level of a steam turbine condenser, although it is not intended for a steel process. In Patent Document 1, the deviation signal between the inlet steam flow rate of the steam turbine measured by the turbine inlet steam flow meter and the condensate flow rate measured by the condensate flow meter corresponds to the opening degree of the condenser level control valve. It is disclosed that the condenser level control valve is controlled by converting it into a condenser level control correction amount and adding it to the output of the PID control that performs constant value control.
Prior art literature
Patent documents
[0004]
Patent Document 1: Japanese Patent Application Laid-Open No. 2012-159024
Patent Document 2: Japanese Patent Application Laid-Open No. 2007-7722
Outline of the invention
Problems to be solved by the invention
[0005]
　In continuous casting, disturbances such as nozzle clogging that fluctuate the flow rate of molten steel injected into the mold and volume fluctuations due to unsteady bulging that fluctuate the molten metal level in the mold may occur. .. Patent Document 1 discloses a configuration in which a control correction amount is added to the output of PID control that performs constant value control, but when this is applied to continuous casting, especially when the latter disturbance occurs, hot water is used. The surface level control performance deteriorates.
[0006]
　The present invention has been made in view of the above points, and it is intended to enable highly accurate control of the molten metal level in the mold even when a plurality of types of disturbances occur in continuous casting. The purpose.
Means to solve problems
[0007]
　The gist of the present invention for solving the above problems is as follows.
(1) The first aspect of the present invention is a continuous casting control device for continuously producing a slab by injecting molten metal into a mold from a nozzle and pulling out the molten metal while solidifying it. The molten metal injected into the mold from the nozzle so that the molten metal level measuring meter for measuring the molten metal level inside and the molten metal level measured by the molten metal level measuring meter follow the target value of the molten metal level. A main control unit that determines the amount of operation of the flow rate adjusting mechanism that adjusts the flow rate of metal, a flow meter that measures the flow rate of molten metal that is injected into the mold from the nozzle, and molten metal that is measured by the flow meter. According to the estimated value of the injection disturbance obtained based on the flow rate measurement value of the above, the injection disturbance correction unit for obtaining the first correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control unit, and the molten metal surface. Withdrawal for obtaining a second correction amount with respect to the operation amount of the flow rate adjusting mechanism obtained by the main control unit according to the estimated value of the drawing disturbance obtained based on the molten metal level measured value measured by the level measuring meter. It is provided with a disturbance correction unit.
(2) The continuous casting control device according to (1) above estimates the flow rate of molten steel according to the opening degree by using a flow rate characteristic model showing the relationship between the operation amount of the flow rate adjusting mechanism and the flow rate of molten metal. The injection disturbance correction unit further includes a flow rate estimation unit for calculating a value, and the injection disturbance correction unit has a flow rate measurement value of the molten metal measured by the flow meter and a flow rate estimation value of the molten metal calculated by the flow rate estimation unit. The difference may be used as an estimated value of the injection disturbance, and the first correction amount may be obtained according to the estimated value of the injection disturbance.
(3) In the continuous casting control device according to (2) above, the injection disturbance correction unit may obtain the first correction amount by using the inverse model of the flow rate characteristic model.
(4) In the continuous casting control device according to (2) or (3) above, the pull-out disturbance correction unit may obtain the second correction amount by using the inverse model of the flow rate characteristic model. ..
(5) The continuous casting control device according to any one of (1) to (4) above is measured by the flow rate measurement value of molten metal measured by the flow meter and the molten metal level meter. Using a process model that expresses the response of the molten metal level to the flow rate of the molten metal by inputting the measured value of the molten metal level, a Ruenberger type observer with the molten metal level and the drawing disturbance as the state variables is constructed and drawn. The pull-out disturbance estimation unit for obtaining an estimated value of the disturbance may be provided, and the pull-out disturbance correction unit may obtain the second correction amount according to the pull-out disturbance estimated value obtained by the pull-out disturbance estimation unit.
(6) In the continuous casting control device according to any one of (1) to (5) above, the flow meter may be an electromagnetic flow meter.
[0008]
(7) A second aspect of the present invention is a method for controlling continuous casting in which a molten metal is injected into a mold from a nozzle and the molten metal is drawn out while solidifying to continuously produce a slab. The molten metal level measuring step in which the molten metal level in the inside is measured by a molten metal level meter, and the molten metal level measured in the molten metal level measurement step are said to be made from the nozzle so as to follow the molten metal level target value. A main control step for obtaining the operation amount of the flow rate adjusting mechanism for adjusting the flow rate of the molten metal injected into the mold, a flow rate measuring step for measuring the flow rate of the molten metal injected into the mold from the nozzle with a flow meter, and a flow rate measuring step. The first correction amount for the operation amount of the flow rate adjusting mechanism obtained in the main control step is adjusted according to the estimated value of the injection disturbance obtained based on the flow rate measurement value of the molten metal measured in the flow rate measurement step. Operation of the flow rate adjusting mechanism obtained in the main control step according to the desired injection disturbance correction step and the estimated value of the withdrawal disturbance obtained based on the molten metal level measurement value measured by the molten metal level meter. It has a pull-out disturbance correction step for obtaining a second correction amount with respect to the amount.
(8) A third aspect of the present invention is a program for controlling continuous casting in which molten metal is continuously produced by injecting molten metal into a mold from a nozzle and pulling out the molten metal while solidifying it. , The amount of operation of the flow rate adjusting mechanism that adjusts the flow rate of the molten metal injected from the nozzle into the mold so that the molten metal level measured by the molten metal level measuring meter follows the target value of the molten metal level. The first with respect to the operation amount of the flow rate adjusting mechanism obtained in the main control step according to the control step and the estimated value of the injection disturbance obtained based on the flow rate measurement value of the molten metal measured by the flow meter. The flow rate adjustment obtained in the main control step according to the injection disturbance correction step for obtaining the correction amount and the estimated value of the withdrawal disturbance obtained based on the molten metal level measurement value measured by the molten metal level meter. It is a program configured to cause a computer to execute a pull-out disturbance correction step for obtaining a second correction amount with respect to the operation amount of the mechanism.
Effect of the invention
[0009]
　According to the present invention, the molten metal level in the mold can be controlled with high accuracy even when a plurality of types of disturbances occur in continuous casting. This makes it possible to improve the quality of slabs and stabilize operations.
A brief description of the drawing
[0010]
FIG. 1 is a diagram showing a schematic configuration of a control system including a continuous casting control device according to an embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a continuous casting control device according to the same embodiment.
FIG. 3 is a block diagram showing a control system of a continuous casting control device according to the same embodiment.
FIG. 4 is a characteristic diagram showing simulation results comparing the method of the present invention with the conventional method.
FIG. 5 is a characteristic diagram showing simulation results comparing the method of the present invention with the conventional method.
FIG. 6 is a characteristic diagram showing simulation results comparing the method of the present invention with the conventional method.
Mode for carrying out the invention
[0011]
　Hereinafter, the continuous casting control device 100 according to the embodiment of the present invention will be described with reference to the accompanying drawings.
[0012]
　FIG. 1 shows a schematic configuration of a continuous casting control system including a continuous casting control device 100 and a continuous casting facility to be controlled.
　The continuous casting facility includes a mold 1 and a dipping nozzle 2, and molten steel is injected into the mold 1 from a tundish (not shown) via the dipping nozzle 2. The mold 1 is water-cooled, and the molten steel in contact with the mold begins to solidify. Molten steel is injected into the mold 1 from the immersion nozzle 2, and the molten steel is pulled out while solidifying to continuously produce slabs.
[0013]
　A molten metal level measuring meter 3 for measuring the molten metal level in the mold 1 is installed near the molten metal surface in the mold 1. Further, the immersion nozzle 2 is provided with an in-nozzle flow rate measuring meter 4 for measuring the flow rate of the molten steel injected into the mold 1. What is the molten steel level measured value measured by the molten metal level measuring meter 3 (that is, the actual molten steel level) and the measured flow rate of molten steel measured by the in-nozzle flow rate measuring meter 4 (that is, the actual flow rate of molten steel)? It is input to the control device 100. As the flow rate measuring meter 4 in the nozzle, for example, an electromagnetic flow meter can be used.
[0014]
　The flow rate of the molten steel injected into the mold 1 from the immersion nozzle 2 is adjusted by the opening degree of the sliding gate 5 which is a flow rate adjusting mechanism (operating end) for adjusting the flow rate of the molten steel. The opening degree of the sliding gate 5 is operated under the control of the control device 100. Although the sliding gate 5 is used in the example shown in FIG. 1, a stopper may be used to adjust the flow rate of molten steel supplied from the immersion nozzle 2.
[0015]
　FIG. 2 shows the configuration of the continuous casting control device 100 according to the present embodiment. The control device 100 includes a main controller 101 (main control unit), a flow rate estimation unit 102, an injection disturbance correction unit 103, a disturbance observer 104, and a pull-out disturbance correction unit 105.
　The main controller 101 determines the molten metal level by obtaining the opening degree u of the sliding gate 5 so that the molten metal level measured value y measured by the molten metal level measuring meter 3 follows the target value of the molten metal level. Perform feedback control to keep it constant. In the following, the opening degree of the sliding gate 5 is simply referred to as an opening degree.
[0016]
　The flow rate estimation unit 102 calculates the flow rate estimation value Q pred of the molten steel according to the current opening degree by using the flow rate characteristic model showing the relationship between the opening degree and the flow rate of the molten steel .
[0017]
　The injection disturbance correction unit 103 sets the difference between the flow rate measurement value Q of the molten steel measured by the in-nozzle flow meter 4 and the flow rate estimation value Q pred of the molten steel calculated by the flow rate estimation unit 102 as the estimated value d of the injection disturbance. 1 ^ and then the estimated value d of the injection disturbance 1 according to ^, obtains the opening correction amount v for opening u. The method of obtaining the estimated value d 1 ^ of the injection disturbance is not limited to this, and may be obtained by a different method as long as it can be obtained using the flow rate measurement value Q. Moreover, d 1 ^ notation d 1 assumed that ^ is attached on top of. Here, a disturbance that causes a fluctuation in the flow rate of the molten steel injected from the immersion nozzle 2 into the mold 1 is referred to as an injection disturbance. Disturbances such as nozzle malfunction, nozzle clogging, clogging peeling, and nozzle melting damage are assumed as the injection disturbance.
[0018]
　The disturbance observer 104 (pull-out disturbance estimation unit) is based on the flow rate measurement value Q of the molten steel measured by the in-nozzle flow rate measuring meter 4 and the molten metal level measurement value y measured by the molten metal level measuring meter 3. Obtain the estimated value d 2 ^ of the withdrawal disturbance . Here, in the continuous casting facility to be controlled, a disturbance that affects the downstream side of the mold 1 and changes the volume balance of molten steel in the mold 1 and affects the molten metal level is called a drawing disturbance. As the pull-out disturbance, a disturbance such as a casting speed error or a volume fluctuation due to unsteady bulging is assumed. The casting speed error represents the difference between the actual value of the casting speed measured from the roll rotation speed and the like and the actual casting speed inside the mold. Normally, in the molten metal level control, when the casting speed is changed, the opening amount of the flow rate adjusting mechanism is corrected based on the correction coefficient calculated in advance according to the casting speed change amount. Here, if there is the above-mentioned casting speed error, the drawing disturbance will occur. The unsteady bulging refers to bulging of a slab that periodically changes with time according to the roll pitch interval.
[0019]
　The pull-out disturbance correction unit 105 obtains an opening degree correction amount w with respect to the opening degree u according to the estimated value d 2 ^ of the pull-out disturbance obtained by the disturbance observer 104 .
[0020]
　As described above, in the control device 100, the opening degree u obtained by the main controller 101 and the opening degree correction amount v and the opening degree correction amount w obtained by the injection disturbance correction unit 103 and the extraction disturbance correction unit 105 are used. The opening degree is determined, and the opening operation of the sliding gate 5 is executed so as to reach this determined opening degree.
[0021]
　FIG. 3 shows a block diagram showing a control system for continuous casting.
　The main controller 101 takes the deviation e between the molten metal level target value and the molten metal level measured value y as an input so that the deviation e becomes 0, that is, the molten metal level measured value y is set to the hot water as described above. The opening degree u is obtained so as to follow the surface level target value.
[0022]
　In the actual plant (continuous casting facility) 200 to be controlled, the flow rate Q is set according to the current opening degree (u + v + w) and the current injection disturbance d 1 according to the plant flow rate characteristic P. Then, the molten metal level y corresponds to the current flow rate Q, the current drawing disturbance d 2, and the current casting speed V c . Note that A represents the cross-sectional area of ​​the mold 1 and s represents the Laplace operator.
[0023]
　The flow rate estimation unit 102 uses the flow rate characteristic model P 0 , which is a nominal model representing the relationship between the opening degree and the flow rate of the molten steel, to form the molten steel according to the current opening degree (u + v + w) as in the equation (1). Calculate the flow rate estimate Q pred . The flow rate characteristic model P 0 is given by a non-linear function, but it may generally be approximated by a straight line by linearizing around the opening operating point.
　Then, as in the equation (2), the difference between the flow rate measurement value Q of the molten steel and the flow rate estimation value Q pred of the molten steel is set as the estimated value d 1 ^ of the injection disturbance . The injection disturbance d to 1 and the flow rate measurement value Q of the molten steel containing, injection disturbance d 1 molten steel flow estimate Q containing no pred by comparing the injection disturbance d 1 can be estimated.
[0024]
[Number 1]

[0025]
　The injection disturbance correction unit 103 uses the inverse model of the flow rate characteristic model P 0 (relational expression representing the opening degree with respect to a given flow rate) P 0 -1 as in the equation (3), and the opening degree correction gain K 1 Is used to obtain the opening correction amount v so as to cancel the estimated value d 1 ^ of the injection disturbance . Similar to the flow rate characteristic model P 0 , the inverse model P 0 -1 is given by a non-linear function, but it may generally be approximated by a straight line by linearizing around the opening operating point.
[0026]
[Number 2]

[0027]
　The disturbance observer 104 is composed of a Luenberger type observer whose state variables are the molten metal level and the withdrawal disturbance, using a process model 1 / As that represents the response of the molten metal level to the flow rate of molten steel. The outline of the calculation in the disturbance observer 104 will be described. Using the process model 1 / As that represents the response of the molten metal level, the molten metal level estimated value y ^ corresponding to the current flow rate measurement value Q of the molten steel is calculated, and the molten metal level measured value y and the molten metal level estimation Based on the difference from the value y ^, the estimated value d 2 ^ of the withdrawal disturbance is obtained . The drawing disturbance d to 2 and the molten metal surface level measurements y containing, drawing disturbance d 2 By comparing the molten metal surface level estimate y ^ containing no, drawing disturbance d 2 can be estimated. It should be noted that the process model 1 / As may be formulated in consideration of the dead time element of hot water falling. Further, the method of obtaining the estimated value d 2 ^ of the withdrawal disturbance is not limited to this, and may be obtained by a different method as long as it can be obtained using the molten metal level measured value y.
[0028]
　Specifically, a step-like disturbance is assumed as a pull-out disturbance, and the disturbance observer is formulated as in the equation (4). L 1 and L 2 are observer gains. In this case, the transfer function from the flow rate measurement value Q of the molten steel and the molten metal level measurement value y to the estimated value d 2 ^ of the extraction disturbance is expressed by Eq. (5). As the pull-out disturbance, a step-shaped disturbance may be generally assumed, but a ramp-shaped disturbance may be assumed, or a periodic disturbance may be assumed.
[0029]
[Number 3]

[0030]
　Here, yQ / As corresponds to the “prediction error” of the molten metal level, and the one passed through the secondary filter L (s) becomes the estimated value d 2 ^ of the extraction disturbance . The filter L (s) is represented by the equation (6). The filter characteristics of the filter L (s) may be appropriately determined according to the expected frequency band of the extraction disturbance. For example, when the peak frequency of the extraction disturbance can be estimated in advance as in unsteady bulging, an appropriate bandpass filter including the peak frequency may be designed.
[0031]
[Number 4]

[0032]
　As shown in equation (7), the pull-out disturbance correction unit 105 uses the inverse model P 0 -1 of the flow rate characteristic model P 0 and uses the opening correction gain K 2 to obtain the estimated value d 2 ^ of the pull-out disturbance. The opening correction amount w is obtained so as to cancel out. Similar to the flow rate characteristic model P 0 , the inverse model P 0 -1 is given by a non-linear function, but it may generally be approximated by a straight line by linearizing around the opening operating point.
[0033]
[Number 5]

[0034]
　The opening correction gains K 1 and K 2 are not limited to positive constants, and a PD controller may be used, for example. Further, the opening correction gains K 1 and K 2 may be changed.
[0035]
　As described above, in the control system that executes feedback control so as to keep the molten metal level constant, a minor loop that suppresses injection disturbance (a loop that includes the injection disturbance correction unit 103) and a minor loop that suppresses extraction disturbance (a loop that suppresses extraction disturbance). By adding the loop including the pull-out disturbance correction unit 105), the molten metal level can be controlled with high accuracy so as to cancel the injection disturbance and the pull-out disturbance. This makes it possible to improve the quality of slabs and stabilize operations.
　In addition, injection disturbance and extraction disturbance can be estimated separately, and deterioration of control performance can be prevented against each disturbance. Then, by obtaining the estimated value of the injection disturbance d 1 , it is used to detect nozzle defects, nozzle clogging, clogging peeling, nozzle melting damage, etc., and take actions for stabilizing the operation (for example, changing the casting speed). It can be connected to the action, the action to change the set value of the electromagnetic force device). Further, by obtaining an estimated value of the extraction disturbance d 2 , a more effective suppression of the periodic disturbance can be achieved by using the estimated value, for example, in combination with the periodic disturbance suppression control method disclosed in Patent Document 2. It will be possible.
[0036]
　In order to confirm the effect of applying the present invention, a simulation of molten metal level control was carried out.
[Simulation conditions of the invention method to which the present invention is applied]
　Assuming typical casting conditions of a continuous casting facility for manufacturing slabs, the following simulation conditions were set and a simulation of molten metal level control was carried out.
　The mold width was set to 1250 mm, the mold thickness was set to 270 mm, the casting speed was set to 1.5 m / m, and the hot water drainage time was set to 0.3 sec.
　The molten metal level target value was set at a position (-100 mm) in the casting direction in the coordinate system with the upper end of the mold as the origin (see the target value shown by the dotted line in FIGS. 4 to 6).
　The main controller 101 was set by the PI controller (proportional gain 0.20, integration time 30 sec), the control cycle was 50 msec, and the PI control was implemented by the speed type.
　Further, the opening correction gains were set to K 1 = 0.3, K 2 = 1.0, observer gain L 1 = 1, and L 2 = L 1 * A.
　The flow rate characteristic model P 0 and its reverse model P 0 -1 are given in a straight line. Since the controller is mounted in the velocity type, it is sufficient to set only the slope without considering the intercept of the straight line.
[0037]
[Simulation content] The conventional method was used in which the
　opening correction gain K 2 = 0. By setting the opening correction gain K 2 = 0, the state is equivalent to that without the minor loop for suppressing the pull-out disturbance, and the method according to the method disclosed in Patent Document 1 is obtained. Then, the results of controlling the level of the molten metal by simulation were compared between the invention method and the conventional method.
　Here, it is difficult to accurately grasp the plant flow rate characteristic P in the actual plant in advance, and in reality, an error occurs in the flow rate characteristic model P 0 , which is a nominal model . As the model error Δ of this flow rate characteristic model P 0 , three types of cases, specifically Δ = 0 (no error), Δ <0 (difficult to generate flow rate), and Δ> 0 (easy to generate flow rate) are set. To do. Then, in each case, a simulation was performed for the cases where (a) injection disturbance d 1 occurred, (b) extraction disturbance d 2 occurred, and (c) injection disturbance d 1 and extraction disturbance d 2 occurred at the same time. .. As shown in FIGS. 4 to 6 described below, injection disturbance d 1 and extraction disturbance d 2Both were assumed to occur at 50 sec. In addition, volume fluctuations equivalent to a flow rate of 10% were taken into consideration for each disturbance. The model error Δ of the flow rate characteristic model P 0 was set to be a 20% decrease in the nominal value (Δ = −0.2) and a 20% increase in the nominal value (Δ = 0.2).
[0038]
[Simulation Results]
　FIGS. 4 to 6 show the simulation results.
　FIG. 4 shows a simulation result when the model error Δ = 0 (no error) of the flow rate characteristic model P 0 . (A) is the response of the molten metal level when the injection disturbance d 1 occurs, (b) is the response of the molten metal level when the extraction disturbance d 2 occurs, and (c) is the response of the injection disturbance d 1 and the extraction disturbance d. The response of the molten metal level when 2 and 2 occur at the same time is shown. As shown in FIG. 4A, when the injection disturbance d 1 occurs, the same result is obtained in both the conventional method and the invention method. On the other hand, as shown in FIGS. 4 (b) and 4 (c), when the withdrawal disturbance d 2 occurs, the fluctuation of the molten metal level cannot be suppressed by the conventional method, but the fluctuation of the molten metal level is not suppressed by the invention method. Can be suppressed. In the conventional method, since the injection disturbance d 1 and the withdrawal disturbance d 2 cannot be distinguished, the effect of suppressing the fluctuation of the molten metal level changes when the withdrawal disturbance d 2 occurs.
[0039]
　Further, FIG. 5 shows a simulation result when the model error Δ = −0.2 (difficult to obtain the flow rate) of the flow rate characteristic model P 0 , and is similar to (a) to (c) in FIG. ) Is the response of the molten metal level when the injection disturbance d 1 occurs, (b) is the response of the molten metal level when the extraction disturbance d 2 occurs, and (c) is the response of the injection disturbance d 1 and the extraction disturbance d 2 . Shows the response of the molten metal level when Again, in the conventional method, since the injection disturbance d 1 and the withdrawal disturbance d 2 cannot be distinguished, the effect of suppressing the fluctuation of the molten metal level fluctuation deteriorates when the withdrawal disturbance d 2 occurs.
　Further, FIG. 6 shows a simulation result when the model error Δ = 0.2 (flow rate is likely to occur) of the flow rate characteristic model P 0 , and (a) is the same as in FIGS. 4 (a) to 4 (c). Is the response of the molten metal level when the injection disturbance d 1 occurs, (b) is the response of the molten metal level when the extraction disturbance d 2 occurs, and (c) is the response of the injection disturbance d 1 and the extraction disturbance d 2Shows the response of the molten metal level when and occurs at the same time. Again, in the conventional method, since the injection disturbance d 1 and the withdrawal disturbance d 2 cannot be distinguished, the effect of suppressing the fluctuation of the molten metal level fluctuation deteriorates when the withdrawal disturbance d 2 occurs.
　As shown in FIGS. 4 to 6, regardless of the model error of the flow rate characteristic model P 0 , the invention method generates injection disturbance d 1 and extraction disturbance d 2 as compared with the conventional method. On the other hand, the effect of suppressing fluctuations in the molten metal level does not deteriorate.
[0040]
　Although the present invention has been described above with the embodiments, the above-described embodiments are merely examples of embodiment of the present invention, and the technical scope of the present invention is construed in a limited manner by these. It should not be. That is, the present invention can be implemented in various forms without departing from the technical idea or its main features.
[0041]
　For example, another aspect of the present invention is a control method for continuous casting in which molten metal is injected into a mold from a nozzle and the molten metal is drawn out while solidifying to continuously produce slabs. From the nozzle to the mold so that the molten metal level measuring step in which the molten metal level is measured by the molten metal level measuring meter and the molten metal level measured in the molten metal level measurement step follow the molten metal level target value. A main control step for obtaining an operation amount of a flow rate adjusting mechanism for adjusting the flow rate of the molten metal to be injected, a flow rate measurement step for measuring the flow rate of the molten metal injected into the mold from the nozzle with a flow meter, and the flow rate Injection to obtain the first correction amount for the operation amount of the flow rate adjusting mechanism obtained in the main control step according to the estimated value of the injection disturbance obtained based on the flow rate measurement value of the molten metal measured in the measurement step. With respect to the operation amount of the flow rate adjusting mechanism obtained in the main control step according to the disturbance correction step and the estimated value of the withdrawal disturbance obtained based on the molten metal level measurement value measured by the molten metal level meter. It is a control method of continuous casting having a pull-out disturbance correction step for obtaining a second correction amount.
[0042]
　Further, the continuous casting control device to which the present invention is applied can be realized by, for example, a computer equipped with a CPU, ROM, RAM and the like.
　The present invention also comprises supplying software (program) that realizes the functions of the present invention to a system or device via a network or various storage media, and the computer of the system or device reads and executes the program. It is feasible.
　Therefore, yet another aspect of the present invention is a program for controlling continuous casting in which molten metal is continuously produced by injecting molten metal into a mold from a nozzle and pulling out the molten metal while solidifying it. Main control for obtaining the operation amount of the flow rate adjusting mechanism that adjusts the flow rate of the molten metal injected from the nozzle into the mold so that the molten metal level measured by the molten metal level measuring meter follows the target value of the molten metal level. The first correction to the operation amount of the flow rate adjusting mechanism obtained in the main control step according to the step and the estimated value of the injection disturbance obtained based on the flow measurement value of the molten metal measured by the flow meter. The flow rate adjusting mechanism obtained in the main control step according to the injection disturbance correction step for determining the amount and the estimated value of the withdrawal disturbance obtained based on the molten metal level measurement value measured by the molten metal level meter. A program configured to cause a computer to execute a pull-out disturbance correction step for obtaining a second correction amount with respect to the operation amount of the above, or a recording medium that can be read by a computer that records the program.
Industrial applicability
[0043]
　According to the present invention, the molten metal level in the mold can be controlled with high accuracy even when a plurality of types of disturbances occur in continuous casting.
Code description
[0044]
　1: Mold, 2: Immersion nozzle, 3: Hot water level meter, 4: In-nozzle flow meter, 5: Sliding gate, 100: Continuous casting control device, 101: Main controller, 102: Flow rate estimation unit, 103: Injection disturbance correction unit, 104: Disturbance observer, 105: Extraction disturbance correction unit
The scope of the claims
[Claim 1]
　A continuous casting control device that continuously produces
　slabs by injecting molten metal into a mold from a nozzle and pulling out the molten metal while solidifying it. and meter,
　the melt-surface levels measured in the melt-surface level meter so as to follow the molten metal surface level target value, the operation amount of the flow rate adjusting mechanism for adjusting the flow rate of the molten metal injected into the mold from the nozzle
　A flow meter that measures the flow rate of the molten metal that is injected into the mold from the nozzle ,
　and an injection disturbance that is obtained based on the flow rate measurement value of the molten metal that is measured by the flow meter. According to the estimated value of, the injection disturbance correction unit that obtains the first correction amount for the operation amount of the flow rate adjusting mechanism obtained by the main control unit, and the
　molten metal level measured value measured by the molten metal level meter. A
continuous casting control device including a pull-out disturbance correction unit for obtaining a second correction amount with respect to the operation amount of the flow rate adjusting mechanism obtained by the main control unit according to an estimated value of the pull-out disturbance obtained based on the above. ..
[Claim 2]
　The
　injection disturbance correction unit further includes a flow rate estimation unit that calculates a flow rate estimation value of molten steel according to the opening degree by using a flow rate characteristic model showing the relationship between the operation amount of the flow rate adjustment mechanism and the flow rate of molten metal. The difference between the flow rate measurement value of the molten metal measured by the flow meter and the flow rate estimation value of the molten metal calculated by the flow rate estimation unit is used as the estimated value of the injection disturbance, and according to the estimated value of the injection disturbance.
The continuous casting control device according to claim 1, wherein the first correction amount is obtained .
[Claim 3]

The continuous casting control device according to claim 2, 　wherein the injection disturbance correction unit uses an inverse model of the flow rate characteristic model to obtain the first correction amount .
[Claim 4]

The continuous casting control device according to claim 2 or 3, 　wherein the pull-out disturbance correction unit uses an inverse model of the flow rate characteristic model to obtain the second correction amount .
[Claim 5]
　A process model that expresses the response of the molten metal level to the flow rate of the molten metal by inputting the flow measurement value of the molten metal measured by the flow meter and the molten metal level measurement value measured by the molten metal level meter is used. It is used to form a Ruenberger-type observer whose state variables are the molten metal level and the pull-out disturbance, and is provided with a pull-out disturbance estimation unit for obtaining an estimated value of the pull-out disturbance. The
　pull-out disturbance correction unit is the pull-out disturbance estimation unit.
The continuous casting control device according to any one of claims 1 to 4 , wherein the second correction amount is obtained according to the obtained estimated value of the pull-out disturbance .
[Claim 6]

The continuous casting control device according to any one of claims 1 to 5, 　wherein the flow meter is an electromagnetic flow meter .
[Claim 7]
　This is a continuous casting control method in which molten metal is injected into a mold from a nozzle and the molten metal is pulled out while solidifying to continuously produce
　slabs . The molten metal level in the mold is measured with a molten metal level meter. a molten metal surface level measuring step of measuring,
　the melt-surface levels measured in the melt-surface level measuring step so as to follow the molten metal surface level target value, adjusting the flow rate of the molten metal injected into the mold from the nozzle a main control step of obtaining an operation amount of the flow rate adjusting mechanism,
　a flow rate measuring step of measuring the flow rate of the molten metal at a flow rate meter which is injected into the mold from the nozzle,
　the flow rate of the molten metal to be measured by the flow rate measuring step According to the estimated value of the injection disturbance obtained based on the measured value, the injection disturbance correction step for obtaining the first correction amount with respect to the operation amount of the flow rate adjusting mechanism obtained in the main control step, and the molten metal
　level measurement. Pull-out disturbance correction for obtaining a second correction amount for the operation amount of the flow rate adjusting mechanism obtained in the main control step according to the estimated value of the pull-out disturbance obtained based on the molten metal level measured value measured by the meter.
A control method for continuous casting with steps .
[Claim 8]
　A program for controlling continuous casting, in which molten metal is injected into a mold from a nozzle and drawn out while solidifying the molten metal to continuously produce
　slabs . The molten metal level measured by a molten metal level meter is used. The main control step for obtaining the operation amount of the flow rate adjusting mechanism that adjusts the flow rate of the molten metal injected from the nozzle into the mold so that the level follows the target value of the molten metal level, and the
　melting measured by the flow meter. An injection disturbance correction step for obtaining a first correction amount with respect to the operation amount of the flow rate adjusting mechanism obtained in the main control step according to an estimated value of the injection disturbance obtained based on the flow rate measurement value of the metal, and the
　hot water. The second correction amount for the operation amount of the flow rate adjusting mechanism obtained in the main control step is obtained according to the estimated value of the pull-out disturbance obtained based on the molten metal level measured value measured by the surface level measuring meter.
A program configured to cause a computer to perform a pull-out disturbance correction step .