Processing device, processing method, and program

Abstract

To bring an outlet-side temperature of a metal strip after switching close to a target value when the metal strip to be cooled is switched.SOLUTION: A processing device 180 calculates a predicted value of an outlet-side temperature of a steel strip located at a predetermined predicted position including a facility midway position in a quenching furnace 111 based on attribute data of the steel strip M and actual data including a blower rotation speed, an inlet-side temperature, and a temperature of the cooling gas. The blower rotation speed R of a predetermined blower installed on the downstream side of the predicted position among the blowers 141a-141d is calculated based on the calculated predicted value of the output side temperature and the target outlet-side temperature.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a processing device, a processing method, and a program, and is particularly suitable for use in continuously cooling a plurality of metal strips that are connected to each other and transported on a transport path. [Background technology]

[0002] A plurality of metal strips are transported to a cooling facility in a state where the rear end of a leading metal strip and the front end of a trailing metal strip are connected to each other by welding or the like, and the plurality of metal strips are continuously cooled in the cooling facility. Patent documents 1 and 2 disclose techniques for controlling the temperature of the metal strips in such cooling facilities.

[0003] Patent Document 1 discloses a method for calculating the ratio of the rotation speeds of the blowers installed in a cooling furnace when the total rotation speed of the blowers is given. Patent Document 2 discloses a method for predicting the outlet temperature of a portion of a metal strip that is located at the inlet position of a cooling zone when the line speed is changed, and for calculating a gas jet pressure such that the outlet temperature after the line speed change is the outlet temperature before the line speed change. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2013 / 084870 [Patent Document 2] JP 2020-63497 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the techniques described in Patent Documents 1 and 2 do not specifically consider the manipulated variables (blower rotation speed, gas jet pressure) when the metal strip to be cooled is switched. When the metal strip to be cooled is switched, the attributes of the metal strip to be cooled (e.g., width, thickness, type) and the target value of the outlet temperature may be changed. In such a case, if the manipulated variables are not appropriately changed, there is a risk that the outlet temperature will deviate from the target value. This may affect the quality of the metal strip and reduce the yield of the metal strip. Therefore, a technique is desired for bringing the outlet temperature of the metal strip after the switch to be cooled closer to the target value when the metal strip to be cooled is switched.

[0006] The present invention has been made in consideration of the above problems, and has an object to bring the outlet temperature of the metal strip after the metal strip to be cooled closer to a target value when the metal strip to be cooled is switched. [Means for solving the problem]

[0007] The processing device of the present invention is a processing device that performs processing to control a cooling equipment that has a plurality of cooling medium supply devices and continuously cools a plurality of metal strips that are connected to each other and transported along a transport path, and is equipped with a data acquisition unit that acquires data including attribute data indicating the attributes of the metal strip, an operation amount for the cooling medium supply devices, actual data including the inlet temperature of the metal strip and the temperature of the cooling medium, and a target value of the outlet temperature corresponding to the metal strip, and an operation amount calculation unit that calculates the operation amount, wherein the operation amount calculation unit calculates a predicted value of the outlet temperature of a portion of the metal strip to be cooled that is located at a predetermined predicted position using the attribute data and the actual data, and calculates the operation amount for a predetermined one of the cooling medium supply devices installed downstream of the predetermined predicted position based on the calculated predicted value of the outlet temperature and the target value of the outlet temperature corresponding to the metal strip, and the predetermined predicted position includes an equipment mid-way position that is a position downstream of the inlet position of the cooling equipment and a position upstream of the outlet position of the cooling equipment.

[0008] The processing method of the present invention is a processing method for performing processing to control a cooling equipment that has a plurality of cooling medium supply devices and continuously cools a plurality of metal strips that are connected to each other and transported on a transport path, the processing method including a data acquisition process for acquiring data including attribute data indicating attributes of the metal strip, an operation amount for the cooling medium supply devices, actual data including the inlet temperature of the metal strip and the temperature of the cooling medium, and a target value of the outlet temperature corresponding to the metal strip, and an operation amount calculation process for calculating the operation amount, wherein the operation amount calculation process calculates a predicted value of the outlet temperature of a portion of the metal strip to be cooled that is located at a predetermined predicted position using the attribute data and the actual data, and calculates the operation amount for a predetermined one of the cooling medium supply devices installed downstream of the predetermined predicted position based on the calculated predicted value of the outlet temperature and the target value of the outlet temperature corresponding to the metal strip, the predetermined predicted position including an intermediate position of the cooling equipment that is downstream of the inlet position of the cooling equipment and upstream of the outlet position of the cooling equipment.

[0009] The program of the present invention causes a computer to function as each part of the processing device. Effect of the Invention

[0010] According to the present invention, when the metal strip to be cooled is switched, the outlet temperature of the metal strip after the switch can be made to approach the target value. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating an example of a cooling facility. [Diagram 2] FIG. 2 illustrates an example of a functional configuration of a processing device. [Diagram 3] FIG. 4 is a diagram conceptually illustrating an example of a relationship between a flow velocity vector and a line velocity vector of a cooling medium. [Figure 4] FIG. 11 is a diagram illustrating an example of a method for calculating an optimal solution of an evaluation function. [Diagram 5]11 is a flowchart illustrating an example of a processing method. [Figure 6] FIG. 11 is a diagram showing an example of the relationship between the set values ​​of the outlet temperature and the blower rotation speed and time. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the term "the same thing" in terms of length, position, size, spacing, etc., includes not only things that are strictly the same, but also things that are different within the scope of the invention (for example, things that differ within the tolerance range determined at the time of design).

[0013] <Cooling equipment> Fig. 1 is a diagram showing an example of a cooling facility. In this embodiment, the cooling facility is a quenching furnace 111 provided in a continuous annealing furnace 110 of a continuous galvanizing line (note that the quenching furnace is also called a quenching zone). Here, an example of an outline of the process in the continuous galvanizing line will be described.

[0014] First, the coil produced in the upper process is set on a pay-off reel (not shown). The coil refers to a metal strip (strip) wound in a coil shape. The coil is unwound from the pay-off reel and transported on the transport path of the continuous hot-dip galvanizing line. The transport path is a space occupied by the steel strips M1 to M4 when the steel strips M1 to M4 pass through, and overlaps with the lines showing the steel strips M1 to M4 in FIG. 1. The steel strips M1 to M4 are transported by the transport rolls 151a to 151i. In the example shown in FIG. 1, the space through which the steel strips M1 to M4 are expected to pass along the transport rolls 151a to 151i becomes the transport path. At least one of the transport rolls 151a to 151i is a transport roll (so-called drive roll) that is rotated by a motor (not shown). The transport rolls 151a to 151i may include a transport roll that is not rotated by a motor (so-called non-driven roll). Furthermore, the transport rolls may be installed at positions different from those of the transport rolls 151a-151i. In Fig. 1, the white arrows shown beside the symbols M1-M4 indicating the steel strips indicate the direction in which the steel strips M1-M4 are transported. The side of the white arrows without the arrowhead is the upstream side in the transport direction of the steel strip M, and the side with the arrowhead is the downstream side in the transport direction of the steel strip M. In the following description, when there is no need to distinguish between the multiple steel strips M1-M4, the multiple steel strips M1-M4 will be referred to as steel strip M as necessary.

[0015] The steel strip M unwound from the pay-off reel is transported to a welding machine (not shown). In the welding machine, the front end of the steel strip M and the rear end of the steel strip M supplied to the continuous hot-dip galvanizing line immediately before the steel strip M are connected to each other. In FIG. 1, a welded portion WP between the rear end of the preceding steel strip M2 and the front end of the following steel strip M3 is indicated by a white circle. After being welded by the welding machine, the steel strip M is transported to a continuous annealing furnace 110 via an inlet looper (not shown) or the like.

[0016] In FIG. 1, the present embodiment illustrates a case where the continuous annealing furnace 110 includes a quenching furnace 111. In addition, in the present embodiment, the quenching furnace 111 is the furnace at the most downstream of the multiple furnaces included in the continuous annealing furnace 110. In this case, the continuous annealing furnace 110 includes, for example, a heating furnace, a soaking furnace, a lehr furnace, and a quenching furnace, in this order from the upstream side. In this case, the steel strip M is heated, for example, in the heating furnace until it reaches a target temperature, and then the state of that temperature is maintained in the soaking furnace. Thereafter, the steel strip M is cooled stepwise in the lehr furnace and the quenching furnace 111 until it reaches a target temperature (for example, room temperature) (lehr cooling and quenching are performed in this order). Note that FIG. 1 shows the heating furnace, the soaking furnace, and the lehr furnace in a simplified manner. Also, the steel strip M being transported through these furnaces is not shown (in FIG. 1, the vertical dashed lines (--------) shown at the leading end and trailing end of the steel strips M4 and M3 in the continuous annealing furnace 110 indicate that the steel strip M is not shown). The continuous annealing furnace 110 itself may be a known one and is not limited to the one described above. For example, a quenching furnace may be provided between the soaking furnace and the annealing furnace, and a final cooling furnace may be provided downstream of the quenching furnace 111.

[0017] The steel strip M continuously annealed in the continuous annealing furnace 110 passes through the hot-dip galvanizing bath in the galvanizing tank 120, and is then wound up on a tension reel (not shown) via an alloying furnace, an outlet looper, a cutter, and the like (not shown). The cutter cuts off a region including a welded portion WP at the rear end of the steel strip M wound up on the tension reel. In this way, in the continuous hot-dip galvanizing line, a plurality of steel strips M are continuously processed. The continuous hot-dip galvanizing line itself may be a known one and is not limited to the one described above.

[0018] Next, an example of the configuration of the quenching furnace 111 will be described. In the quenching furnace 111, cooling control of the steel strip M is performed for each of a plurality of zones separated in the conveying direction of the steel strip M (direction along the conveying path). Figure 1 illustrates an example in which cooling control in the quenching furnace 111 is performed for each of four zones. In the following explanation, the four zones of the quenching furnace 111 in Figure 1 will be referred to as the first zone, second zone, third zone, and fourth zone, in that order from the upstream side, as necessary. Note that the number of zones is not limited to four, and may be two or more. In addition, the quenching furnace 111 does not have to be (explicitly) divided into a plurality of zones.

[0019] In FIG. 1, the entry thermometer 131 measures the entry temperature of the steel strip M. The entry temperature of the steel strip M is the temperature when (each portion of) the steel strip M passes through the entry position. The entry position is a position on the conveying path corresponding to the entrance of the cooling equipment (in this embodiment, the quenching furnace 111). In this embodiment, the position where the entry thermometer 131 measures the entry temperature is the entry position, and an example is shown in which the entry position is the entrance L1 of the first zone.

[0020] In FIG. 1, the outlet thermometer 132 measures the outlet temperature of the steel strip M. The outlet temperature of the steel strip M is the temperature when (each part of) the steel strip M passes through the outlet position. The outlet position is the position of the transport path corresponding to the outlet of the cooling equipment (the quenching furnace 111 in this embodiment). In this embodiment, the position where the outlet thermometer 132 measures the outlet temperature is the outlet position, and the outlet position is the outlet L5 of the fourth zone. Also, in FIG. 1, this embodiment illustrates a case where the entrance L2 of the second zone, the entrance L3 of the third zone, and the entrance L4 of the fourth zone coincide with the exit of the first zone, the exit of the second zone, and the exit of the third zone, respectively. Therefore, the entrance L2 of the second zone, the entrance L3 of the third zone, and the entrance L4 of the fourth zone are the boundary between the first and second zones, the boundary between the second and third zones, and the boundary between the third and fourth zones, respectively.

[0021] In this embodiment, an example is shown in which the boundaries (entrance and exit) of each zone are determined by the distance in the conveying direction from the entrance position (entrance L1 of the first zone). A detector for measuring the temperature, etc. of the steel strip M may be installed at the boundary of each zone. In this case, the position of the conveying path corresponding to the installation position of the detector (the position where the detector measures the temperature, etc. of the steel strip M) may be the position of the boundary of each zone.

[0022] The blowers 141a to 141d supply (blow) gas to the steel strip M during transportation. The air around the blowers 141a to 141d may be directly supplied to the blowers 141a to 141d, or separately cooled air may be supplied. In the following description, the gas supplied from the blowers 141a to 141d to the steel strip M will be referred to as cooling gas as necessary. In this embodiment, a case will be illustrated in which the cooling gas is output from the blowers 141a to 141d in a direction perpendicular to the surface (strip face) of the steel strip M.

[0023] In the present embodiment, the blower 141a supplies cooling gas to the steel sheet M being transported through the first zone. Similarly, the blowers 141b, 141c, and 141d supply cooling gas to the steel sheet M being transported through the second zone, the third zone, and the fourth zone, respectively. The gas thermometers 133a, 133b, 133c, and 133d measure the temperature of the cooling gas supplied from the blowers 141a, 141b, 141c, and 141d toward the steel strip M, respectively. In the following description, the temperatures measured by the gas thermometers 133a to 133d will be referred to as gas temperatures as necessary.

[0024] 1, for convenience of notation, the gas thermometers 133a-133d are shown at positions away from the spaces between the blowers 141a-141d and the steel strip M, but it is preferable that the gas thermometers 133a-133d measure the temperature of the spaces between the blowers 141a-141d and the steel strip M as the gas temperature. In other words, the gas temperature is preferably the temperature (ambient temperature) of the area within the quenching furnace 111 through which the cooling gas passes. Although not shown in Figure 1, in this embodiment, an opening that can be opened and closed is formed in the wall surface of the quenching furnace 111, and cooling gas from blowers 141a to 141d is supplied to the steel strip M being transported inside the quenching furnace 111 through the opening.

[0025] FIG. 1 illustrates an example in which blowers 141a to 141d are provided for each zone. However, this is not necessarily required. For example, multiple blowers may be provided for each zone. The number of blowers provided for each zone may be the same or different. This embodiment illustrates an example in which blowers 141a to 141d are cooling medium supply devices, and the cooling medium is gas (gas). However, the cooling medium supply devices are not limited to blowers, and the cooling medium is not limited to gas. For example, the cooling medium supply devices and the cooling medium may be cooling spray and water (liquid), respectively.

[0026] The motors 142a, 142b, 142c, and 142d are motors for driving the blowers 141a, 141b, 141c, and 141d, respectively. The rotation speed measuring devices 134a, 134b, 134c, and 134d measure the rotation speeds of the motors 142a, 142b, 142c, and 142d, respectively. In this embodiment, the case is illustrated in which the rotation speeds of the motors 142a, 142b, 142c, and 142d match the (fan) rotation speeds of the blowers 141a, 141b, 141c, and 141d, respectively. Therefore, the rotation speeds measured by the rotation speed measuring devices 134a, 134b, 134c, and 134d are the rotation speeds of the blowers 141a, 141b, 141c, and 141d, respectively. In the following description, the rotation speeds of the blowers 141a to 141d will be referred to as blower rotation speeds, as necessary.

[0027] The rotation speed measuring devices 134a to 134d include, for example, a pulse generator and a computer. The pulse generator outputs, for example, one pulse signal every time the motors 142a to 142d rotate once. The computer calculates the blower rotation speed (the rotation speed of the motors 142a to 142) based on the pulse signal generated by the pulse generator. The inverters 143a, 143b, 143c, and 143d are power supply devices for driving the motors 142a, 142b, 142c, and 142d, respectively. Note that the driving of the motors 142a, 142b, 142c, and 142d is not limited to inverter driving. As described above, in this embodiment, the case is exemplified where the controlled element is the motor 142a to 142d, and the controlled amount is the blower rotation speed. However, the controlled element and the controlled amount differ depending on the cooling medium supplying device. For example, when the cooling medium supplying device is a cooling spray, the controlled element may be a valve for adjusting the supply amount of cooling medium (water) to the cooling spray, and the controlled amount may be the opening degree of the valve.

[0028] The line speed measuring device 135 measures the conveying speed of the steel strip M. The line speed measuring device 135 includes, for example, a pulse generator and a computer. The pulse generator generates, for example, one pulse signal each time the conveying roll 151g rotates once. The computer calculates the time required for the conveying roll 151g to rotate once based on the pulse signal generated by the pulse generator, and calculates the conveying speed of the steel strip M based on the calculated time and the circumferential length of the conveying roll 151g (=diameter of the conveying roll 151g x pi). In the following description, the conveying speed of the steel strip M measured by the line speed measuring device 135 is referred to as the line speed as necessary. Note that, when the conveying roll 151g is a conveying roll (so-called driving roll) rotated by a motor (not shown), the conveying roll 151g may be rotated by the motor so as to have a rotation speed corresponding to a set value of the conveying speed of the steel strip M. The set value of the conveying speed of the steel strip M is determined, for example, according to the attributes of the steel strip M being conveyed through the continuous hot-dip galvanizing line, the operating status of the continuous hot-dip galvanizing line, etc. Also, the pulse generator provided in the line speed measuring device 135 may be configured to generate one pulse signal every time the motor rotates once.

[0029] The sequencer 160 performs processing including acquiring performance data obtained in the quenching furnace 111 and outputting it to the processing device 180 described later, and outputting the set value of the blower rotation speed outputted from the processing device 180 as described later to an inverter among the inverters 143a to 143d that needs to be changed to the set value. In this embodiment, a case where the performance data includes an inlet temperature, an outlet temperature, a gas temperature, a blower rotation speed, and a line speed is illustrated. In addition, in this embodiment, a case where the performance data is updated at a predetermined control period s, and the sequencer 160 repeatedly acquires the performance data at the control period s is illustrated. Note that the value of the performance data after the update may be the same as the value of the performance data before the update. Also, the line speed may not be included in the performance data. In this case, a set value may be used as the line speed. In addition, in this embodiment, a case where the sequencer 160 repeatedly outputs the set value of the blower rotation speed at the control period s is illustrated.

[0030] The inverters 143a to 143d rotate the motors 142a to 142d so that the rotation speed of the motors 142a to 142d becomes the set value of the blower rotation speed output from the sequencer 160.

[0031] The management device 170 is a device (computer) for managing the operation of the continuous hot-dip galvanizing line. The management device 170 outputs to the processing device 180 information that the processing device 180 needs to acquire in advance as information required when the processing device 180 performs processing. The management device 170 outputs, for example, attribute data of the steel strip M and a target value of the outlet temperature corresponding to the steel strip M to the processing device 180. In the following description, the target value of the outlet temperature will be referred to as a target outlet temperature as necessary.

[0032] The attribute data of the steel strip M includes, for example, identification information of multiple steel strips M to be cooled, information indicating the attributes of the steel strips M identified by the identification information, and information indicating the manufacturing order (transport order) of the steel strips M identified by the identification information. The attributes of the steel strip M include, for example, thickness, width, length, mass, type, and physical property values. The target outlet temperature of the steel strip M is output to the processing device 180 so that it is possible to identify which steel strip M the target outlet temperature belongs to. For example, the target outlet temperature of the steel strip M may be linked to the attribute data of the steel strip M, or may be linked to the identification information of the steel strip M.

[0033] <Processing device 180> Next, a description will be given of an example of the configuration of the processing device 180. The processing device 180 performs processing for controlling a cooling facility (the quenching furnace 111 in this embodiment). 2 is a diagram showing an example of a functional configuration of the processing device 180. The processing device 180 has, as hardware, one or more hardware processors such as a CPU (Central Processing Unit) and one or more memories such as a RAM (Random Access Memory) and a ROM (Read Only Memory), and executes various calculations by executing one or more programs stored in the memory by the one or more hardware processors. Furthermore, the processing device 180 has, as hardware, an input device and an output device.

[0034] <<Data Acquisition Unit 181>> The data acquisition unit 181 acquires data including attribute data indicating the attributes of the metal strip, performance data including the operation amount for the cooling medium supply device, the inlet temperature of the metal strip, and the temperature of the cooling medium, and a target value for the outlet temperature (target outlet temperature) corresponding to the metal strip.

[0035] In this embodiment, an example is shown in which the data acquisition unit 181 acquires performance data of the steel strip M from the sequencer 160. Also, in this embodiment, an example is shown in which the data acquisition unit 181 repeatedly acquires performance data of the steel strip M at a control period s. As described above, in this embodiment, an example is shown in which the performance data includes the inlet temperature, the outlet temperature, the gas temperature, the blower rotation speed, and the line speed.

[0036] Furthermore, in this embodiment, an example is given of the data acquisition unit 181 acquiring attribute data and a target outlet temperature from the management device 170. Furthermore, in this embodiment, an example is given of the attribute data and target outlet temperature of a steel strip M being acquired when the steel strip M passes through the entry position. However, this is not necessarily required. For example, the data acquisition unit 181 may acquire the transport schedule of each steel strip M (such as the scheduled time for each steel strip M to arrive at the entry position) and the attribute data of each steel strip M before acquiring the actual data of each steel strip M.

[0037] Incidentally, the processing device 180 may have some or all of the functions of the sequencer 160 and the management device 170 .

[0038] <<Operation amount calculation unit 182>> The operation amount calculation unit 182 calculates an operation amount for the cooling medium supplying device. In this embodiment, the operation amount calculation unit 182 calculates the blower rotation speed.

[0039] Specifically, in this embodiment, the operation amount calculation unit 182 calculates a predicted value of the exit temperature of a part (part passing through the predetermined predicted position) at a predetermined predicted position among the parts of the metal strip to be cooled, using attribute data and performance data of the metal strip. Here, the predetermined predicted position includes one or more equipment midway positions. The equipment midway position is a position of the transport path that is downstream of the entrance position of the cooling equipment and upstream of the exit position of the cooling equipment. In this embodiment, a case is illustrated in which the entrance position of the cooling equipment and the exit position of the cooling equipment are the position of the transport path corresponding to the entrance L1 of the first zone and the position of the transport path corresponding to the exit L5 of the fourth zone, respectively. In addition, in this embodiment, a case is illustrated in which the equipment midway position is the position of the transport path corresponding to the entrance L2 of the second zone, the entrance L3 of the third zone, and the entrance L4 of the fourth zone. In addition, in this embodiment, a case is illustrated in which the position of the transport path corresponding to the entrance L1 of the first zone is also included in the predetermined predicted position. Therefore, in this embodiment, an example is shown in which the operation amount calculation unit 182 calculates a predicted value of the exit temperature (temperature at the conveying path position corresponding to the fourth zone exit L5) of the portion of the steel strip M to be cooled, which is located at the conveying path positions corresponding to the first to fourth zone inlets L1 to L4. In the following explanation, the conveying path positions corresponding to the first to fourth zone inlets L1 to L4 and the conveying path position corresponding to the fourth zone exit L5 are abbreviated as the first to fourth zone inlets L1 to L4 and the fourth zone exit L5, as necessary.

[0040] In addition, in this embodiment, the operation amount calculation unit 182 calculates the predicted value of the outlet temperature of the part of the steel strip M to be cooled, which is located at the inlets L2 to L4 of the second to fourth zones, by using the actual data obtained in the region of the quenching furnace 111 upstream of the inlets L2 to L4 of the second to fourth zones. For example, when calculating the predicted value of the outlet temperature of the part of the steel strip M to be cooled, which is located at the inlet L2 of the second zone, the operation amount calculation unit 182 uses the actual data obtained in the first zone. Similarly, when calculating the predicted value of the outlet temperature of the part of the steel strip M to be cooled, which is located at the inlets L3 and L4 of the third and fourth zones, the operation amount calculation unit 182 uses the actual data obtained in the first to second zones and the first to third zones, respectively. In addition, in this embodiment, the operation amount calculation unit 182 calculates the predicted value of the outlet temperature of each part of the steel strip M before the tip of the steel strip M to be cooled reaches the outlet position. In addition, this embodiment illustrates a case where the operation amount calculation unit 182 repeatedly calculates, for each control period s, a predicted value of the outlet temperature of each portion of the steel strip M. In the following description, the portion of the steel strip M to be cooled will be referred to as a steel strip portion, as necessary.

[0041] Here, an example of a prediction formula for calculating a predicted value of the outlet temperature will be described. In this embodiment, the following prediction formula (1) will be used as an example. T_pr[t+d]=Tg[t]+(Ti[t-d']-Tg[t-d'])·exp{-(H[t+d]·d+H[t-d']·d')}+e[t+d]···(1)

[0042] t is the current time. In this embodiment, the current time t is updated at the time step of the control period s. d is the time assumed to be required for the steel strip portion at the predicted position to reach the exit position (exit L5 of the fourth zone) from the predicted position. This time d may be calculated, for example, assuming that the future line speed is the line speed at the current time t, or that the future line speed is accelerated or decelerated according to the time change (i.e., acceleration / deceleration) of the line speed at the current time t, or may be calculated in other ways (for example, based on an operation schedule). d' is the time required for the steel strip portion at the predicted position to reach the predicted position from the entry position (entrance L1 of the first zone). In the following description, the time d' is referred to as the predicted position arrival time d' as necessary.

[0043] In this embodiment, the operation amount calculation unit 182 performs tracking of the steel strip M. Tracking is a technique for tracking the position of a moving object. For example, when a detector (not shown) for detecting the welded portion WP transported on the transport path between an inlet looper (not shown) and the continuous annealing furnace 110 is installed in a continuous hot-dip galvanizing line, the operation amount calculation unit 182 can calculate the position of each steel strip portion of the steel strip M on the transport path in the continuous annealing furnace 110 at the current time t based on the line speed at each control cycle s from the time when the welded portion WP is detected by the detector, the length of the steel strip M (length from the front end to the rear end), and the location of the transport path (coordinates indicating the position of the space occupied by the transport path). Note that tracking may be started, for example, from a welding machine (not shown). Since tracking itself can be realized by a known technique, a detailed description thereof will be omitted here.

[0044] As described above, in this embodiment, the boundary (entrance and exit) of each zone is determined by the distance in the conveying direction from the entrance position (entrance L1 of the first zone). In addition, in this embodiment, the length in the conveying direction of each zone and the position of the entrance L1 of the first zone are preset in the processing device 180.

[0045] Therefore, the operation amount calculation unit 182 can calculate the time d' required to reach the predicted position based on the tracking result, the length of each zone in the transport direction, and the position of the entrance L1 of the first zone. In the following description, the length of the zone in the transport direction will be abbreviated to the zone length as necessary.

[0046] In equation (1), T_pr[t+d] is the predicted value of the exit temperature at time t+d. That is, T_pr[t+d] is the predicted value of the exit temperature of the steel strip part at the predicted position at time t. Here, the times required for the steel strip M to pass through the first zone, the second zone, the third zone, and the fourth zone are s1, s2, s3, and s4, respectively. In this case, the predicted value of the exit temperature of the steel strip part at the entrance L1 of the first zone at time t is expressed as T_pr[t+s1+s2+s3+s4] (i.e., d=s1+s2+s3+s4). Similarly, the predicted values ​​of the exit temperature of the steel strip part at the entrances L2, L3, and L4 of the second, third, and fourth zones at time t are expressed as T_pr[t+s2+s3+s4], T_pr[t+s3+s4], and T_pr[t+s4], respectively.

[0047] In formula (1), Tg[t] is the actual value of the temperature (gas temperature) of the cooling gas supplied to the steel strip portion at the predicted position (the inlets L1 to L4 of the first to fourth zones) at time t. In this embodiment, the case where Tg[t] is the actual value of the temperature of the cooling gas at the center position of the zone whose inlet is the predicted position is illustrated. For example, when the predicted position is the inlet L1 of the first zone, Tg[t] is the actual value of the temperature of the cooling gas at the center position of the first zone at the current time t. The center position of the first zone is the position of the conveying path that is equidistant in the conveying direction from both the inlet L1 of the first zone and the inlet L2 of the second zone. Similarly, in this embodiment, when the predicted position is the inlets L2, L3, and L4 of the second, third, and fourth zones, the case where Tg[t] is the actual value of the temperature of the cooling gas at the stop position of the second, third, and fourth zones at the current time t is illustrated. 1, for convenience of notation, blowers 141a and 141d are not shown at positions corresponding to the centers of zones 1 and 4, respectively, but when Tg[t] is determined as described above, blowers 141a and 141d are installed so as to be able to supply cooling gas to regions including the centers of zones 1 and 4. When Tg[t] is determined as described above, gas thermometers 133a to 133d are installed so as to be able to measure the gas temperature at positions as close as possible to the centers of each zone (preferably the centers of each zone).

[0048] In formula (1), Ti[t-d'] is the actual value of the entry temperature at time t-d'. In other words, Ti[t-d'] is the actual value of the entry temperature of the steel strip part at the predicted position (the entrances L1-L4 of the first to fourth zones) at time t. When the predicted position is the entrance L1 of the first zone, the time required to reach the predicted position d' is 0 (zero), so Ti[t-d'] is the actual value of the entry temperature Ti[t] at the current time t.

[0049] In formula (1), H[t+d] is expressed as the product of the sum of the heat transfer coefficients in the zone whose inlet is the prediction position (the inlets L1 to L4 of the first to fourth zones) at time t and the zone downstream of the prediction position, and a constant determined for each steel strip portion (steel strip M). The heat transfer coefficient is the heat transfer coefficient between the steel strip M and the atmosphere in the furnace. For example, when the prediction position is the inlet L3 of the third zone, H[t+d] is expressed as the product of the sum of the heat transfer coefficient h3 in the third zone and the heat transfer coefficient h4 in the fourth zone, and a constant determined for each steel strip M. The constant determined for each steel strip M is, for example, the value obtained by dividing the surface area by the product of the density, specific heat, and volume (=surface area÷(density×specific heat×volume)). The surface area, density, specific heat, and volume are obtained, for example, based on the attribute data of the steel strip M.

[0050] In equation (1), H[t-d'] is expressed as the product of the sum of the heat transfer coefficients in the zone upstream of the zone whose inlet is the prediction position and a constant determined for each steel strip portion (steel strip M) when calculating the predicted value of the outlet temperature of the steel strip portion at the prediction position at time t. For example, when the prediction position is the inlet L2 of the second zone, H[t-d'] is expressed as the product of the heat transfer coefficient h1 in the first zone and a constant determined for each steel strip M. When the prediction position is the inlet L3 of the third zone, H[t-d'] is expressed as the product of the sum of the heat transfer coefficient h1 in the first zone and the heat transfer coefficient h2 in the second zone and a constant determined for each steel strip M. Similarly, when the predicted position is the entrance L4 of the fourth zone, H[t-d'] is expressed as the product of the sum of the heat transfer coefficients h1 in the first zone, h2 in the second zone, and h3 in the third zone, and a constant determined for each steel strip M. When the predicted position is the entrance L1 of the first zone, the time required to reach the predicted position d' is 0 (zero). Therefore, when the predicted position is the entrance L1 of the first zone, H[t-d']·d' in equation (1) becomes 0 (zero).

[0051] In this embodiment, an example is shown in which the heat transfer coefficient is expressed as the heat transfer coefficient under forced convection when a cooling medium is applied perpendicularly to the surface (strip surface) of the steel strip M. The heat transfer coefficient h under forced convection is expressed, for example, by the following formula (2). h=0.664 λ Re 1 / 2 ·Pr 1 / 3 / L...(2)

[0052] where λ is the thermal conductivity. Re is a value obtained by dividing the product of the flow velocity of the cooling medium and the length of the zone by the dynamic viscosity coefficient (=flow velocity×length of the zone÷dynamic viscosity coefficient). In this embodiment, the case where the flow velocity of the cooling medium is converted from the blower rotation speed is illustrated. Pr is the value obtained by dividing the dynamic viscosity coefficient by the thermal conductivity of the cooling medium (dynamic viscosity coefficient ÷ thermal conductivity). In this embodiment, the heat transfer coefficient, the dynamic viscosity coefficient, and the thermal conductivity are set in advance in the processing device 180. However, for example, the data acquisition unit 181 may acquire them from the management device 170.

[0053] In this embodiment, the flow velocity of the cooling medium used in calculating the heat transfer coefficients h1 to h4 is calculated based on the blower rotation speed R. The actual value of the blower rotation speed used in calculating the heat transfer coefficients h1 to h4 differs depending on the predicted position. For example, when the predicted position is the entrance L4 of the fourth zone, the heat transfer coefficient h1 is calculated using the actual value R(t-s3-s2-s1÷2) of the blower rotation speed of the blower 141a at the time t-s3-s2-s1÷2. That is, the heat transfer coefficient h1 is calculated using the blower rotation speed R(t-s3-s2-s1÷2) of the blower 141a when the steel strip part at the entrance L4 of the fourth zone passes the center position of the first zone at the current time t. Similarly, the heat transfer coefficients h2 and h3 are calculated using the actual values ​​R(t-s3-s2÷2) and R(t-s3÷2) of the blower rotation speed of the blowers 141b and 141c at the times t-s3-s2÷2 and t-s3÷2, respectively. That is, the heat transfer coefficients h2 and h3 are calculated using the blower rotation speeds R(t-s3-s2÷2) and R(t-s3÷2) of the blowers 141b and 141c when the steel strip portion at the entrance L4 of the fourth zone passes through the center positions of the second and third zones at the current time t. On the other hand, when the predicted position is the entrance L4 of the fourth zone, the steel strip portion at the entrance L4 of the fourth zone does not pass through the center position of the fourth zone. The blower rotation speed R(t+s4÷2) of the blower 141d when passing through the center position of the fourth zone is calculated as an unknown quantity. In this case, the blower 141d installed for the fourth zone is an example of a predetermined cooling medium supply device.

[0054] Similarly, when the predicted position is the inlet L3 of the third zone, the heat transfer coefficients h1 and h2 are calculated using the actual values ​​R(t-s2-s1÷2) and R(t-s2÷2) of the blower rotation speeds of the blowers 141a and 141b at the times t-s2-s1÷2 and t-s2÷2, respectively. On the other hand, the blower rotation speeds R(t+s3÷2) and R(t+s3+s4÷2) of the blowers 141c and 141d when passing through the center positions of the third and fourth zones are calculated as unknowns. In this case, the blowers 141c to 141d installed for the third to fourth zones are examples of predetermined cooling medium supplying devices.

[0055] When the predicted position is the inlet L2 of the second zone, the heat transfer coefficient h1 is calculated using the actual value R(t-s1÷2) of the blower rotation speed of the blower 141a at time t-s1÷2. On the other hand, the blower rotation speeds R(t+s2÷2), R(t+s2+s3÷2), and R(t+s2+s3+s4÷2) of the blowers 141b, 141c, and 141d when passing through the center positions of the second, third, and fourth zones are calculated as unknowns. In this case, the blowers 141b to 141d installed for the second to fourth zones are examples of predetermined cooling medium supplying devices.

[0056] When the predicted position is the inlet L1 of the first zone, the blower rotation speeds R(t+s1÷2), R(t+s1+s2÷2), R(t+s1+s2+s3÷2), and R(t+s1+s2+s3+s4÷2) of the blowers 141a, 141b, 141c, and 141d when passing through the center positions of the first, second, third, and fourth zones are calculated as unknowns. In this case, the blowers 141a to 141d installed for the first to fourth zones are an example of a predetermined cooling medium supplying device.

[0057] In addition, when the blower rotation speeds of the multiple zones are unknown, for example, the ratio of the blower rotation speeds of the multiple zones may be set to a predetermined value. For example, the ratio of the blower rotation speeds of the multiple zones may be predetermined so that the blower rotation speeds of the multiple zones are the same value, or the blower rotation speed of the downstream zone may be predetermined to be higher than the blower rotation speed of the upstream zone, or the blower rotation speed of the upstream zone may be predetermined to be higher than the blower rotation speed of the downstream zone.

[0058] In this embodiment, an example is shown in which the temperature of a steel strip portion located at a predicted position at the current time t when the steel strip portion reaches the exit position is calculated using "Tg[t]+(Ti[t-d']-Tg[t-d'])·exp{-(H[t+d]·d+H[t-d']·d')}" in equation (1). In this embodiment, "Tg[t]+(Ti[t-d']-Tg[t-d'])·exp{-(H[t+d]·d+H[t-d']·d')}" in equation (1) is an example of a physical model. Using equation (1), the temperature at the exit position of the steel strip portion is calculated when a temperature change occurs in the steel strip portion due to forced convection heat transfer occurring between the steel strip portion and its surroundings during the period in which the steel strip portion located at a predicted position at the current time t is transported from the predicted position to the exit position.

[0059] In this embodiment, a physical model is obtained by modifying a known model such as that described in Patent Document 2. That is, in the known model, a model is created for each zone by setting the initial temperature and predicted temperature of the metal strip as the inlet and outlet temperatures of each zone, respectively. Then, the predicted temperature calculated by the model of a zone one zone downstream of a certain zone is set as the initial temperature of the model of the certain zone, and this is repeated for all the models of the zones in sequence. By expressing the model obtained in this way as one mathematical formula, formula (1) is obtained.

[0060] e[t+d] is a correction amount for correcting an error in a physical model. In the following description, the correction amount for correcting an error in a physical model is referred to as an error correction amount of a physical model as necessary. The type of error in a physical model to be corrected by the error correction amount of a physical model may be determined according to the physical model and the cooling equipment. In this embodiment, the following cases are exemplified as errors in a physical model that are corrected by the error correction amount of a physical model.

[0061] As described above, this embodiment illustrates a case in which the cooling gas is output from the blowers 141a-141d in a direction perpendicular to the surface (strip surface) of the steel strip M. Also, as described above, this embodiment illustrates a case in which the heat transfer coefficient is expressed as the heat transfer coefficient under forced convection when the cooling medium strikes the surface (strip surface) of the steel strip M perpendicularly. However, since the cooling medium strikes the steel strip M during transportation, the cooling medium strikes the surface (strip surface) of the steel strip M at an angle.

[0062] Therefore, the relationship between the flow velocity vector V of the cooling medium and the line speed vector v is as shown in FIG. 3. The larger the angle θ shown in FIG. 3, the more the angle at which the cooling medium hits the surface (strip surface) of the steel strip M deviates from the direction perpendicular to the surface (strip surface) of the steel strip M (θ=0°). The magnitude of the flow velocity vector V of the cooling medium corresponds to the blower rotation speed R. The direction of the flow velocity vector V of the cooling medium corresponds to the direction in which the cooling gas is supplied. Therefore, the degree of error caused by the change in the direction in which the cooling medium hits the steel strip M depending on the line speed and the speed of the cooling medium can be expressed by arctan(v / R). In this embodiment, the blower rotation speed R of the blower set downstream of the inlet of the zone, which is the predicted position, among the blowers 141a to 141d is calculated as an unknown quantity. Therefore, by calculating the error correction amount e[t+d] of the physical model using the correction amount for correcting the error expressed by the blower rotation speed R among the errors of the physical model, the blower rotation speed R, which is an unknown quantity, can be calculated taking into account the error of the physical model. In this embodiment, the correction amount for the metal strip transportation-induced error is expressed by using arctan(v / R), and the correction amount for the metal strip transportation-induced error is used to calculate the error correction amount e[t+d] of the physical model. Specifically, in this embodiment, the correction amount for the metal strip transportation-induced error is expressed by arctan(v / R) at the time when the steel strip part at the predicted position passes (or has passed) the center position of each zone.

[0063] In addition, in this embodiment, an example is shown in which the error correction amount e[t+d] of the physical model is calculated using correction amounts for errors including, in addition to the metal strip transportation-induced error, the position calculation error, the metal strip propagation heat quantity error, and the cooling medium temperature change error, as errors of the physical model that are corrected by the error correction amount e[t+d] of the physical model.

[0064] The position calculation error is an error caused by calculating (tracking) the position of a part of a metal strip (steel strip part) (i.e., the calculated value of the position differs from the actual value). The inlet temperature of the same metal strip M does not vary greatly. On the other hand, the inlet temperatures of two metal strips M connected by a welded part WP may differ greatly depending on the attributes of the metal strip M. Therefore, if the time change of the inlet temperature Ti is large when the same metal strip M is cooled, it can be said that the calculated value of the position of the part of the metal strip (steel strip part) differs greatly from the actual position. Therefore, the degree of the position calculation error can be expressed by the time change of the inlet temperature Ti. In this embodiment, a case is illustrated in which the correction amount for the position calculation error is expressed by the difference between the inlet temperature Ti of the steel strip part at the predicted position and the inlet temperature Ti at the time one control cycle s before and one control cycle s after the time when the inlet temperature Ti is obtained.

[0065] In this embodiment, a case is illustrated in which the heat quantity propagating in the length direction of the metal strip (steel strip M) is not taken into consideration in the physical model. The metal strip propagation heat quantity error is an error caused by the heat quantity propagating in the length direction of the metal strip (steel strip M). When the difference between the heat quantity of the metal strip (steel strip M) at the entry position (entrance L1 of the first zone) and the heat quantity of the metal strip (steel strip M) at the exit position (exit L5 of the fourth zone) at the same time is large, it can be said that the heat quantity propagating in the length direction of the metal strip (steel strip M) is large. Therefore, the degree of the metal strip propagation heat quantity error can be expressed by the difference between the heat quantity of the steel strip M at the entry position and the heat quantity of the steel strip M at the exit position at the same time. In this embodiment, a case is illustrated in which the correction amount for the metal strip propagation heat quantity error is expressed by the difference (the difference between the heat quantity of the steel strip M at the entry position and the heat quantity of the steel strip M at the exit position) at the time when the steel strip part at the predicted position passes (or has passed) the entrance and exit positions of each zone. The heat quantity of a metal strip (steel strip M) is expressed, for example, as the product of the width W, thickness TH, and temperature of the metal strip M.

[0066] In this case, the heat quantity of the steel strip M at the entry position at a certain time is expressed, for example, as the product of the width W and thickness TH of the steel strip M (=W×TH) and the entry temperature Ti at that time (=W×TH×Ti). The heat quantity of the steel strip M at the exit position at a certain time is expressed, for example, as the product of the width and thickness of the steel strip M (=W×TH) and the exit temperature To at that time (=W×TH×To). As described above, this embodiment illustrates a case in which attribute data of the steel strip M is acquired when the steel strip M passes through the entry position. Therefore, the attribute data of the steel strip M passing through the exit position at a certain time is acquired when the steel strip M passes through the entry position.

[0067] Cooling medium temperature change error is an error caused by the change in the temperature of the cooling medium in a certain zone when a metal strip (steel strip M) passes through that zone. The degree of the cooling medium temperature change error can be expressed by the change in the temperature of the cooling medium in the same zone over time. In this embodiment, an example is shown in which the correction amount for the cooling medium temperature change error is expressed by the absolute value of the difference between the temperature of the cooling medium in that zone at the time when (or the time when) the steel strip portion at the predicted position passes through the center position of each zone and the temperature of the cooling medium in that zone at the time one cycle prior to that time.

[0068] As described above, in this embodiment, the error of the physical model corrected by the error correction amount e[t+d] of the physical model includes the metal strip transportation-induced error, the position calculation error, the metal strip propagation heat amount error, and the cooling medium temperature change error. The error correction amount e[t+d] of the physical model is calculated so that the value calculated by the physical model is changed more as these errors become larger. In addition, in this embodiment, the case where there are multiple types of errors in the physical model (specifically, four types) is illustrated. Therefore, in this embodiment, the prediction formula of formula (1) is illustrated by using a multiple regression formula (multiple regression model) in which the predicted value T_pr[t+d] of the outlet temperature or the error correction amount e[t+d] of the physical model is a dependent variable, and the correction amount for the metal strip transportation-induced error, the correction amount for the position calculation error, the correction amount for the metal strip propagation heat amount error, and the correction amount for the cooling medium temperature change error are each an independent variable. Note that using the predicted value T_pr[t+d] of the outlet temperature as a dependent variable is equivalent to using the error correction amount e[t+d] of the physical model as a dependent variable. In other words, when using the predicted value T_pr[t+d] of the outlet temperature as a dependent variable, for example, a formula in which e[t+d] on the right side of equation (1) is given an error correction amount calculation formula for correcting the error of the predicted value of the outlet temperature calculated by the physical model becomes a multiple regression formula. On the other hand, when the error correction amount e[t+d] of the physical model is used as the dependent variable, for example, by transferring Tg[t]+(Ti[t-d']-Tg[t-d'])·exp{-(H[t+d]·d+H[t-d']·d')} from the right-hand side of equation (1) to the left-hand side, the multiple regression equation is obtained by giving e[t+d] on the right-hand side of equation (1) an error correction amount calculation equation for correcting the error in the predicted value of the outlet temperature calculated by the physical model.

[0069] Here, an example of an error correction amount calculation formula for correcting the error of the predicted value of the outlet temperature calculated by the physical model, which is given to e[t+d] in formula (1), is explained. For example, when calculating the predicted value T_pr[t+s3+s4] of the outlet temperature of the steel strip part located at the entrance L3 of the third zone at time t, the error correction amount e[t+d] (=e[t+s3+s4]) of the physical model is expressed by the following formula (3). e[t+s3+s4]=a0 +b0·(Ti[t-s2-s1]-Ti[t-s2-s1-s])+b1·(Ti[t-s2-s1+s]-Ti[t-s2-s1]) +c0·(Ti[t+s3+s4]·TH[t+s3+s4]·W[t+s3+s4]-To[t+s3+s4]·TH[t-s4-s3-s2-s1]·W[t-s4-s3-s2-s1])+c1·(Ti[t+s3]·TH[t+s3]·W[t+s3]-To[t+s3]·TH[t-2·s4-s3-s2-s1]·W[t-2·s4-s3-s2-s1])+c2·(Ti[t]·TH[t]·W[t]-To[t]·TH[t-2·s4-2·s3-s2-s1]·W[t-2·s4-2·s3-s2-s1])+c3·(Ti[t-s2]·TH[t-s2]·W[t-s2])-To[t-s2]·TH[t-2·s4-2·s3-2·s2-s1]·W[t-2·s4-2·s3-2·s2-s1])+c4·(Ti[t-s2-s1]·TH[t-s2-s1]·W[t-s2-s1]-To[t-s2-s1]·TH[t-2·s4-2·s3-2·s2-2·s1]·W[t-2·s4-2·s3-2·s2-2·s1]) +d0·arctan(v[t+s3+s4 / 2] / R[t+s3+s4 / 2])+d1·arctan(v[t+s3 / 2] / R[t+s3 / 2])+d2·arctan(v[t-s2 / 2] / R[t-s2 / 2])+d3·arctan(v[t-s2-s1 / 2] / R[t-s2-s1 / 2]) +e0·ΔTg[t+s3+s4 / 2]+e1·ΔTg[t+s3 / 2]+e2·ΔTg[t-s2 / 2]+e3·ΔTg[t-s2-s1 / 2] ···(3) a0 is a constant term (intercept). From the viewpoint of more accurately correcting the errors in the physical model, it is preferable that the constant term a0 is set to a value other than 0 (zero) based on the results of multiple regression analysis, but the constant term a0 may be fixed at 0 (zero). b0 and b1 are regression coefficients relating to the amount of correction for the position calculation error. c0, c1, c2, c3, and c4 are regression coefficients relating to the amount of correction for the metal strip propagation heat quantity error. d0, d1, d2, and d3 are regression coefficients relating to the amount of correction for the metal strip transportation-induced error. e0, e1, e2, and e3 are regression coefficients relating to the amount of correction for the cooling medium temperature change error.

[0070] In the example shown in equation (3), "arctan(v[t+s3+s4 / 2] / R[t+s3+s4 / 2]," "arctan(v[t+s3 / 2] / R[t+s3 / 2])," "arctan(v[t-s2 / 2] / R[t-s2 / 2])," and "arctan(v[t-s2-s1 / 2] / R[t-s2-s1 / 2])," which represent the correction amounts for errors caused by metal strip transportation, are respectively arctan(v / R) at the time when the steel strip portion at the predicted position, L3 at the entrance of the third zone, passes (or has passed) the center positions of the fourth zone, the third zone, the second zone, and the first zone.

[0071] In addition, "(Ti[t-s2-s1]-Ti[t-s2-s1-s])" and "(Ti[t-s2-s1+s]-Ti[t-s2-s1])", which represent the correction amount for the position calculation error, are respectively the difference between the entry temperature Ti of the steel strip portion at the entrance L3 of the third zone, which is the predicted position, and the entry temperature Ti one control cycle s before the time when the entry temperature Ti of the steel strip portion was obtained, and the difference between the entry temperature Ti one control cycle s after the time when the entry temperature Ti of the steel strip portion at the entrance L3 of the third zone, which is the predicted position, was obtained, and the entry temperature Ti of the steel strip portion.

[0072] In addition, the correction amount for the metal band propagation heat error is expressed as "(Ti[t+s3+s4]·TH[t+s3+s4]·W[t+s3+s4]-To[t+s3+s4]·TH[t-s4-s3-s2-s1]·W[t-s4-s3-s2-s1])" and "(Ti[t+s3]·TH[t+s3]·W[t+s3]-To[t+s3]·T H[t-2 s4-s3-s2-s1] W[t-2 s4-s3-s2-s1]), (Ti[t] TH[t] W[t]-To[t] TH[t-2 s 4-2·s3-s2-s1]·W[t-2·s4-2·s3-s2-s1])”, “(Ti[t-s2]·TH[t-s2]·W[t-s2])-To[t-s2] and (Ti[t-s2-s1]·TH[t-s2-s1]·W[t-s2-s1]-To[t-s2-s1]·TH[t-2·s4-2·s3-2·s2-2·s1]·W[t-2·s4-2·s3-2·s2-2·s1]) are the difference between the heat quantity of the steel strip M at the entry position and the heat quantity of the steel strip M at the exit position at the time (or the time when the steel strip portion at the predicted position, L3, at the entrance L3 of the third zone passes (or has passed) the exit L5 of the fourth zone, the entrance L4 of the fourth zone, the entrance L3 of the third zone, the entrance L2 of the second zone, and the entrance L1 of the first zone, respectively.

[0073] "ΔTg[t+s3+s4 / 2]", "ΔTg[t+s3 / 2]", "ΔTg[t-s2 / 2]", and "ΔTg[t-s2-s1 / 2]", which represent the correction amount for the cooling medium temperature change error, are respectively the absolute value of the difference between the gas temperature of the corresponding zone at the time (or the time at which) the steel strip portion at the entrance L3 of the third zone, which is the predicted position, passes through (or has passed through) the center positions of the fourth zone, the third zone, the second zone, and the first zone, and the gas temperature of the corresponding zone at a time one control cycle s before that time.

[0074] In addition, except for the blower rotation speed R, values ​​at times after the current time t may use, for example, the actual value at the current time t. For example, Ti[t] may be used as Ti[t+s3+s4]. Meanwhile, for the blower rotation speed R, values ​​at times after the current time t are calculated as unknowns. When there are blower rotation speeds R that are unknowns in multiple zones, as described above, the ratio of the blower rotation speeds of the multiple zones may be set to a predetermined value. In the example shown in formula (3), for example, these values ​​may be calculated as unknowns so that R[t+s3+s4 / 2] and R[t+s3 / 2] are the same value.

[0075] In this embodiment, an example is shown in which an error correction amount calculation formula for correcting an error in a predicted value of the outlet temperature calculated by a physical model can be obtained as in the above formula (3). Also, in this embodiment, a correction amount for an error caused by metal strip transportation, a correction amount for a position calculation error, a correction amount for an error in the amount of heat propagated by the metal strip, and a correction amount for an error in a change in the temperature of the cooling medium are calculated by the error correction amount calculation formula, and a prediction formula (formula (1)) is expressed by using a regression formula including these correction amounts as independent variables. In addition, the error correction amount e[t+d] (=e[t+s1+s2+s3+s4], =e[t+s2+s3+s4], =e[t+s4]) of the physical model when calculating the predicted values ​​T_pr[t+s1+s2+s3+s4], T_pr[t+s2+s3+s4] of the outlet temperatures of the steel strip parts at the entrance L1 of the first zone, the entrance L2 of the second zone, and the entrance L4 of the fourth zone can also be obtained by changing the time of each variable in equation (3) according to the target zone. Therefore, here, the specific equations for the error correction amount e[t+d] of these physical models are omitted.

[0076] As described above, in this embodiment, an example is shown in which the operation amount calculation unit 182 uses actual data repeatedly acquired by the data acquisition unit 181 at a control period s to repeatedly calculate, at a current time t corresponding to the control period s, the predicted value T_pr[t+d] of the outlet temperature of the steel strip portions located at the entrance L1 of the first zone, the entrance L2 of the second zone, the entrance L3 of the third zone, and the entrance L4 of the fourth zone, using equation (1) at a control period s.

[0077] In this embodiment, the operation amount calculation unit 182 calculates the blower rotation speed R of the blower 141a-141d installed downstream of the predicted position based on the predicted value T_pr[t+d] of the outlet temperature of the steel strip part located at the entrances L1-L4 of the first to fourth zones, which are the predicted positions, and the target outlet temperature T_aim of the steel strip M to which the steel strip part belongs. As described above, when calculating the formula (1), the blower rotation speed R when passing through the center position of the zone downstream of the predicted position is unknown. The operation amount calculation unit 182 may search by trial and error for the blower rotation speed R at which the absolute value or square value of the difference between the predicted value T_pr[t+d] of the outlet temperature of the steel strip part located at the entrances L1-L4 of the first to fourth zones, which are the predicted positions, and the target outlet temperature T_aim of the steel strip M to which the steel strip part belongs is less than a predetermined value (preferably 0 (zero)). However, doing so may result in a long calculation time. Also, there is a risk that the blower rotation speed R must be significantly changed. Furthermore, there is a risk that the blower rotation speed R that cannot be realized by the blowers 141a to 141d may be calculated. Therefore, in this embodiment, a case will be illustrated in which the operation amount calculation unit 182 calculates the blower rotation speed R as follows.

[0078] First, in this embodiment, a case will be illustrated in which the manipulated variable calculation unit 182 calculates an optimal solution of the evaluation function J of the following equation (4). J=w ΔT 2 +ΔR 2 (4) ΔT is expressed by the following formula (5). In the following description, ΔT will be referred to as the prediction error ΔT of the outlet temperature as necessary. In this embodiment, ΔT is an example of a first evaluation index for evaluating the difference between the predicted value of the outlet temperature of a part at a predetermined prediction position and the target value of the outlet temperature. ΔT = T_pr[t+d] - T_aim (5) In this embodiment, a case is exemplified in which the target delivery temperature T_aim for one steel strip M is constant. However, the target delivery temperature T_aim for one steel strip M may vary. For example, the target delivery temperature T_aim for one steel strip M may be different at the front end, the center, and the rear end.

[0079] ΔR is a change amount with respect to the current value of the blower rotation speed R. In the following description, ΔR will be referred to as the blower rotation speed change amount ΔR as necessary. In this embodiment, the blower rotation speed change amount ΔR is an example of a second evaluation index for evaluating a change amount of an operation amount for a predetermined cooling medium supplying device. Using the blower rotation speed change amount ΔR is preferable because it can prevent the blower rotation speed R from being changed significantly or the blower rotation speed R that cannot be realized by the blowers 141a to 141d from being calculated. However, for example, when there is a margin in the capacity of the inverters 143a to 143d and the blowers 141a to 141d, the blower rotation speed change amount ΔR does not need to be included in the evaluation index.

[0080] w is a weighting coefficient. The weighting coefficient w is used to balance the evaluation of the prediction error ΔT of the outlet temperature and the change amount ΔR of the blower rotation speed. In this embodiment, a case where a minimization problem is solved to minimize the value of the evaluation function J of the formula (5) is illustrated. In this case, for example, the weighting coefficient w is set to a positive value. When the weighting coefficient w is set to a positive value and the prediction error ΔT of the outlet temperature is set as an important evaluation index, the value of the weighting coefficient w is increased. Conversely, when the change amount ΔR of the blower rotation speed is set as an important evaluation index, the value of the weighting coefficient w is decreased. Note that a maximization problem to maximize the value of the evaluation function may be solved. In this case, the evaluation function may be, for example, each term on the right side of the formula (5) multiplied by (-1).

[0081] 4 is a diagram for explaining an example of a method for calculating an optimal solution of the evaluation function J. In this embodiment, a case is illustrated in which the blower rotation speed change amount ΔR is a decision variable that is determined as a solution (optimal solution) when the value of the evaluation function J is minimized. Note that the value of the evaluation function J being minimized corresponds to the value of the evaluation function J being determined to be minimum in an algorithm that searches for an optimal solution. For example, when the value of the evaluation function J is equal to or less than a predetermined value, the value of the evaluation function J may be determined to be minimum.

[0082] When solving a minimization problem that minimizes the value of the evaluation function J in equation (5), the minimum value of the evaluation function J can be obtained, for example, by searching for a minimum value of the evaluation function J. The minimum value of the evaluation function J is the value of the evaluation function J when the value obtained by differentiating the evaluation function J with respect to the blower rotation speed change amount ΔR is 0 (zero). When there are multiple minimum values ​​of the evaluation function J, the minimum value of the evaluation function J corresponding to the multiple minimum values ​​becomes the minimum value of the evaluation function J within the search range for the optimal solution. In the following explanation, the function J'(ΔR) obtained by expressing the value obtained by differentiating the evaluation function J with respect to the blower rotation speed change amount ΔR as a function of the blower rotation speed change amount ΔR will be referred to as the differential function J'(ΔR) of the evaluation function as necessary.

[0083] In this embodiment, the operation amount calculation unit 182 performs numerical analysis to calculate an optimal solution of the blower rotation speed change amount ΔR (the blower rotation speed change amount ΔR when the value of the evaluation function J is minimized). From the viewpoint of shortening the search time (calculation time) for the optimal solution, for example, the Newton method may be used as a numerical analysis method. However, in a method such as the Newton method, even if a solution exists in the search range of the optimal solution, there is a risk that the solution will not converge (the solution will diverge). Therefore, in this embodiment, a numerical analysis method in which a method in which a solution is always calculated when a solution exists in the search range of the solution is used is exemplified. In this embodiment, a numerical analysis method in which the Brent method is used is exemplified. However, such a numerical analysis method is not limited to the Brent method. For example, the bisection method (only) may be used.

[0084] Next, an example of the search range for the optimal solution will be described. The range of the blower rotation speed change amount ΔR can be determined based on the current value of the blower rotation speed R of the blowers 141a to 141d and the allowable range of the blower rotation speed R (upper and lower limits of the blower rotation speed R). The allowable range of the blower rotation speed R is determined, for example, based on the specifications of the blowers 141a to 141d. For example, the upper and lower limits of the blower rotation speed R are the upper and lower limits of the blower rotation speed R, respectively, determined in the specifications as the usable range of the blowers 141a to 141d.

[0085] Here, the lower limit and upper limit of the blower rotation speed R are expressed as 0% and 100%, respectively, and the value of the blower rotation speed R is expressed as a percentage of the upper limit. In this case, the lower limit of the search range of the optimal solution is expressed as, for example, a value obtained by subtracting the current value of the blower rotation speed (the blower rotation speed included in the performance data of the control period s corresponding to the current time t) from the margin value (>0) for the lower limit of the blower rotation speed R (=0%). If the margin value for the lower limit of the blower rotation speed R is 5% and the current value of the blower rotation speed is 50%, the lower limit of the blower rotation speed change amount ΔR is -45% (=5%-50%). Moreover, the upper limit of the search range of the optimal solution is expressed as a value obtained by subtracting the current value of the blower rotation speed R from the upper limit of the blower rotation speed R, and further subtracting the margin value (>0) for the upper limit of the blower rotation speed R (=100%). If the margin value for the lower limit of the blower rotation speed R is 5% and the current value of the blower rotation speed is 50%, the upper limit of the blower rotation speed change amount ΔR is 45% (=100%-50%-5%).

[0086] The margin value for the lower limit of the blower rotation speed R is provided to prevent the blower rotation speed R from reaching the lower limit (0%). The margin value for the upper limit of the blower rotation speed R is provided to prevent the blower rotation speed R from reaching the upper limit (100%). In this way, these margins are provided to set the search range for the optimal solution to a range with a margin for the upper and lower limit values ​​in the specifications of the blowers 141a to 141d.

[0087] Furthermore, the margin value for the lower limit of the blower rotation speed R and the margin value for the upper limit of the blower rotation speed R may be the same value or different values. Furthermore, these margin values ​​may be determined individually for some or all of the blowers 141a to 141d, or may be the same for all of the blowers 141a to 141d. In this embodiment, a case is illustrated in which these margin values ​​are set in advance in the processing device 180. The allowable range of the blower rotation speed R may be acquired from the management device 170 by the data acquisition unit 181, for example.

[0088] In this embodiment, a case is exemplified where the search range for the optimal solution of the evaluation function J is calculated based on the cooling medium supply capacity of a predetermined cooling medium supply device (in this embodiment, the upper and lower limits of the blower rotation speed R of the blowers 141a to 141d). In this way, it is possible to prevent the blower rotation speed R that cannot be realized by the blowers 141a to 141d from being calculated as the optimal solution.

[0089] In Fig. 4, the manipulated variable calculation unit 182 may calculate (search) the optimal solution from the entire search range of the optimal solution at once. However, in the example shown in formulas (1) to (5), the evaluation function J is composed of many types of actual values. In such a case, the evaluation function J (and the differential function J'(ΔR) of the evaluation function) changes with the fluctuation of the many types of actual values, and the number of minimum and maximum values ​​of the evaluation function J is not determined within the search range of the optimal solution. Even in such a case, in order to prevent the solution from not converging or a local optimal solution from being calculated, this embodiment illustrates a case in which the manipulated variable calculation unit 182 calculates an optimal solution for the blower rotation speed change amount ΔR within the search range of the optimal solution as follows.

[0090] First, as shown in FIG. 4, the operation amount calculation unit 182 divides the search range of the optimal solution calculated as described above into a plurality of small search ranges, and selects a small search range that satisfies a predetermined necessary condition for the optimal solution to exist from among the divided plurality of small search ranges. FIG. 4 illustrates a case where the search range of the optimal solution is equally divided into 10 small search ranges. However, the small search ranges may not be equally divided, and a solution range (range of the blower rotation speed change amount ΔR) may be determined for each of some or all of the small search ranges. If the number of small search ranges is small (wide), there is a high possibility that multiple extreme values ​​exist in one small search range. On the other hand, if the number of small search ranges is large (narrow), the calculation load increases. From this viewpoint, the number of small search ranges (width of the small search range) is determined in advance based on the results of numerical simulations and simulation experiments.

[0091] In addition, this embodiment illustrates a case where a minimization problem is solved to minimize the value of the evaluation function J. Therefore, this embodiment illustrates a case where a predetermined necessary condition for an optimal solution to exist within a search range for the optimal solution is to satisfy the following (A). (A) At the lower limit a and upper limit b of the small search range, J'(a)<0 and J'(b)>0 are satisfied. The above (A) is an example of a condition indicating that at least one minimum value of the evaluation function J is included within the small search range. If a minimum value of the evaluation function J is included within the small search range, there is a possibility that the minimum value of the evaluation function J is included within the small search range. Therefore, in this case, the necessary condition for the existence of an optimal solution within the search range of the optimal solution is satisfied. Note that the value of the evaluation function J indicating the minimum value is not necessarily the minimum value of the evaluation function J within the search range of the optimal solution. Therefore, even if the above (A) is satisfied, it cannot be said that the necessary and sufficient condition for the existence of an optimal solution within the search range of the optimal solution is satisfied.

[0092] In FIG. 4, of the ten small search ranges, the three small search ranges including points 411 to 413 contain the blower rotation speed change amount ΔR where the differential function J′(ΔR) of the evaluation function is 0 (zero). Of these three small search ranges, J'(a1)<0 and J'(b1)>0 hold in the small search range that includes point 411. Similarly, J'(a3)<0 and J'(b3)>0 hold in the small search range that includes point 413. Therefore, these two small search ranges satisfy (A) above.

[0093] On the other hand, in the small search range including point 412, J'(a2)>0 and J'(b2)<0, and J'(a2)<0 and J'(b2)>0 do not hold. Therefore, this small search range does not satisfy (A) above. Note that the small search ranges other than the three small search ranges including points 411-413 do not satisfy (A) above, because the positive and negative signs of J'(a) and J'(b) are the same.

[0094] 4, the operation amount calculation unit 182 determines that at least one minimum value of the evaluation function J exists in the two small search ranges including the points 411 and 413, and selects the two small search ranges including the points 411 and 413 from the ten small search ranges. Note that the point 412 is a point indicating a maximum value of the evaluation function J.

[0095] The operation amount calculation unit 182 calculates the optimal solution of the evaluation function J in the small search range selected as described above as a candidate for the optimal solution of the evaluation function J in the search range of the optimal solution. As described above, in this embodiment, the case where the Brent method is used as a method of numerical analysis is illustrated. Therefore, in the example shown in FIG. 4, the operation amount calculation unit 182 calculates the blower rotation speed change amount ΔR that minimizes the value of the evaluation function J in the small search range as a candidate for the optimal solution of the evaluation function J in the search range of the optimal solution by using the Brent method for each of the two small search ranges including 411 and point 413. In this way, in the example shown in FIG. 4, two candidates for the optimal solution of the evaluation function J in the search range of the optimal solution are calculated. Note that the Brent method itself is realized by a known technology, so a detailed explanation of the solution method using the Brent method will be omitted here. It is preferable to use a method such as the Brent method in which a solution is always calculated when a solution exists in the search range of the solution, since it is possible to suppress the solution from not converging in the small search range. However, if an optimal solution is searched for within a small search range, the selection range of the initial value is narrower than when the initial value is selected from the search range of the optimal solution. Therefore, even if a method such as Newton's method is used, the possibility that the solution will not converge can be reduced compared to when the optimal solution is searched for from the entire search range of the optimal solution. Therefore, the optimal solution of the evaluation function J in the small search range may be calculated using a method (e.g., Newton's method) that does not necessarily calculate the solution if the solution exists within the search range of the solution.

[0096] FIG. 4 illustrates a case where the evaluation function J has a minimum value in the search range of the optimal solution (i.e., the differential function J' (ΔR) of the evaluation function has 0 (zero)) (see points 411, 413). However, there may be cases where the evaluation function J does not have a minimum value in the search range of the optimal solution. Therefore, in this embodiment, an example is shown where the operation amount calculation unit 182 further calculates the value of the evaluation function J when using the blower rotation speed change amount ΔR (a1 in the example shown in FIG. 4) indicating the lower limit of the search range of the optimal solution, and the value of the evaluation function J when using the blower rotation speed change amount ΔR (b3 in the example shown in FIG. 4) indicating the upper limit of the search range of the optimal solution.

[0097] Then, the operation amount calculation unit 182 selects the minimum value of the evaluation function J calculated in each small search range that satisfies (A) above and the value of the evaluation function J calculated using the blower rotation speed change amount ΔR indicating the lower and upper limits of the search range for the optimal solution. The operation amount calculation unit 182 sets the blower rotation speed change amount ΔR used in calculating the selected value of the evaluation function J as the optimal solution of the evaluation function J in the search range for the optimal solution.

[0098] Then, the operation amount calculation unit 182 calculates (determines) a value obtained by adding the blower rotation speed change amount ΔR calculated as the optimal solution of the evaluation function J in the optimal solution search range to the current value of the blower rotation speed R as the set value (updated value) of the blower rotation speed. The operation amount calculation unit 182 performs the above-mentioned calculation of the set value of the blower rotation speed for each of the blowers 141a to 141d that is installed downstream of the predicted position (i.e., calculates each set value of the blower rotation speed R, which is the unknown quantity described above). Also, as described above, in this embodiment, the operation amount calculation unit 182 repeatedly calculates the above-mentioned set value of the blower rotation speed at the control period s.

[0099] <<Output unit 183>> The output unit 183 outputs information indicating the set value of the blower rotation speed calculated by the operation amount calculation unit 182 and information on the blowers, among the blowers 141a to 141d, whose blower rotation speed needs to be updated to the set value, to the sequencer 160. As described above, in this embodiment, the output unit 183 repeatedly outputs this information at the control period s. Based on this information, the sequencer 160 outputs the set value of the blower rotation speed to each of the inverters 143a to 143d.

[0100] <<Regression coefficient calculation unit 184>> As described above, in this embodiment, the case where the prediction formula is expressed by a regression formula is exemplified (see formulas (1) and (3)). The constant terms and regression coefficients in the prediction formula (regression formula) are calculated, for example, by multiple regression analysis using teacher data. In this case, the teacher data is created, for example, by using actual data (entrance temperature, exit temperature, blower rotation speed, gas temperature, line speed) acquired by the data acquisition unit 181. In this case, for example, actual data for the same steel strip part is taken as one teacher data. The exit temperature included in the teacher data is a so-called correct answer label. As such teacher data, a number of teacher data necessary for multiple regression analysis is created. In this embodiment, the regression coefficient calculation unit 184 performs multiple regression analysis using such teacher data to obtain the constant terms and regression coefficients in the prediction formula (regression formula). As a method of multiple regression analysis, for example, a sequential least squares method with a forgetting factor is used. Since the regression analysis method itself is realized by a known technology, a detailed description of the regression analysis is omitted here. The constant terms and regression coefficients in the prediction formula (regression formula) may be calculated for at least one piece of information (e.g., steel type) included in the attributes of the steel strip M. In this case, a prediction formula (regression formula) for each piece of information can be used.

[0101] In addition, this embodiment illustrates a case where the regression coefficient calculation unit 184 calculates (updates) the constant terms and regression coefficients in the prediction equation (regression equation) online (while controlling the blower rotation speed for cooling the steel strip M to be cooled) when a predetermined learning condition is met.

[0102] For example, the predetermined learning condition may be satisfied when a predetermined operating condition is satisfied. For example, the learning condition may be satisfied when the portion at the inlet position (the steel strip portion in this embodiment) is a middle portion. The middle portion is a portion that is neither near the front end nor near the rear end, and is, for example, a portion from a position closer to the rear end by a predetermined value than the front end to a position closer to the front end by a predetermined value than the rear end. Also, the learning condition may be satisfied when the line speed is equal to or greater than a predetermined value. In this way, the predetermined learning condition may be a condition that is determined to be satisfied or not based on actual data. Note that the constant terms and regression coefficients in the prediction formula (regression formula) may be updated offline. For example, the constant terms and regression coefficients in the prediction formula (regression formula) may be set and changed by trial and error so as to improve the performance of the cooling control based on the results of the cooling control when the processing device 180 is applied to actual operation.

[0103] After calculating the constant term and the regression coefficient in the prediction formula (regression formula), the regression coefficient calculation unit 184 outputs these values ​​to the operation amount calculation unit 182. The operation amount calculation unit 182 calculates the error correction amount e[t+d] of the physical model using the constant term and the regression coefficient. Note that, if the constant term and the regression coefficient in the prediction formula (regression formula) are updated in this way, it is preferable that the calculation accuracy of the error correction amount e[t+d] of the physical model is improved. However, the constant term and the regression coefficient in the prediction formula (regression formula) do not have to be updated.

[0104] <Flowchart> Next, an example of a processing method using the processing device 180 of this embodiment will be described with reference to the flowchart of FIG. 5. Here, a case where the flowchart of FIG. 5 is repeatedly executed at a control period s will be illustrated. Note that the flowchart of FIG. 5 ends based on at least one of an instruction from an operator to the processing device 180 and an instruction from the management device 170, for example. Also, for the sake of simplicity, a case where information that needs to be acquired in advance when the processing device 180 calculates the set value of the blower rotation speed is acquired before the flowchart of FIG. 5 starts will be illustrated.

[0105] First, in step S501, the processing device 180 determines whether or not the leading end of the steel strip M has passed the entry position (entrance L1 of the first zone) based on the tracking result. If the result of this determination is that the leading end of the steel strip M has not passed the entry position (NO in step S501), step S502 is omitted and the processing of step S503 described below is performed.

[0106] On the other hand, if the result of the judgment in step S501 is that the front end of the steel strip M has passed the entry position (YES in step S501), processing in step S502 is performed. In step S502, the data acquisition unit 181 acquires attribute data and the target exit temperature of the steel strip M. Also, in step S502, the data acquisition unit 181 may delete the actual data for the steel strip M whose rear end is connected to the front end of the steel strip M via a welded portion WP (i.e., the steel strip M that is cooled in the quenching furnace 111 just before the steel strip M).

[0107] Next, in step S503, the data acquiring unit 181 acquires performance data. In this embodiment, the performance data includes the inlet temperature, the outlet temperature, the gas temperature, the blower rotation speed, and the line speed.

[0108] Next, in step S504, the regression coefficient calculation unit 184 determines whether or not a predetermined learning condition for learning (updating) the constant term and the regression coefficient in the prediction formula (regression formula) is satisfied. If the result of this determination is that the predetermined learning condition is not satisfied (NO in step S504), the processes in steps S505 to S506 are omitted and the process in step S507 described below is performed.

[0109] On the other hand, if the predetermined learning condition is satisfied (YES in step S504), the process of step S505 is performed. In step S505, the regression coefficient calculation unit 184 calculates the constant term and the regression coefficient in the prediction formula (regression formula) by performing multiple regression analysis (for example, sequential least squares with forgetting factor). Next, in step S506, the manipulated variable calculation section 182 updates the constant term and the regression coefficient in the prediction equation (regression equation) to the values ​​calculated in step S505.

[0110] Next, in step S507, the operation amount calculation unit 182 calculates the blower rotation speed change amount ΔR based on the predicted value T_pr[t+d] of the outlet temperature of the steel strip part located at the inlets L1 to L4 of the first to fourth zones, which are the predicted positions, and the target outlet temperature T_aim of the steel strip M to which the steel strip part belongs. As described with reference to FIG. 4, in this embodiment, the operation amount calculation unit 182 first sets a search range for an optimal solution and divides the search range for the optimal solution into a plurality of small search ranges. Then, the operation amount calculation unit 182 selects a small search range that satisfies the above (A) from the plurality of small search ranges, and calculates the minimum value of the evaluation function J in each of the selected small search ranges. Then, the operation amount calculation unit 182 selects the minimum value among the minimum value of the evaluation function J calculated in each of the selected small search ranges and the value of the evaluation function J calculated from the blower rotation speed change amount ΔR that indicates the lower and upper limits of the search range for the optimal solution, and sets the blower rotation speed change amount ΔR used to calculate the selected minimum value (the value of the evaluation function J) as the optimal solution of the evaluation function J in the search range for the optimal solution.

[0111] Next, in step S508, the operation amount calculation unit 182 calculates the setting value of the blower rotation speed by adding the blower rotation speed change amount ΔR calculated in step S507 as the optimal solution of the evaluation function J in the search range for the optimal solution to the current value of the blower rotation speed R.

[0112] Finally, in step S509, the output unit 183 outputs information indicating the set value of the blower rotation speed calculated in step S508 and information on the blower among the blowers 141a to 141d that needs to update the blower rotation speed R to the set value, to the sequencer 160. Fig. 5 illustrates an example in which the process according to the flowchart in Fig. 5 ends when the process of step S509 ends.

[0113] <Calculation example> Next, a calculation example will be described, however, the present invention is not limited to this calculation example. In this calculation example, offline simulations were performed on operations in a continuous hot-dip galvanizing line using the method of the invention example and the method of the comparative example.

[0114] The method of the invention example is the method described in the present embodiment. The method of the comparative example is a method in which feedforward control is performed until the actual value of the outlet temperature of the steel strip to be cooled is obtained, and when the actual value of the outlet temperature of the steel strip to be cooled is obtained, feedback control is performed using the actual value of the outlet temperature and the target outlet temperature. The feedforward control was performed by calculating the total blower rotation speed based on a preset value and allocating the total blower rotation speed equally to each blower.

[0115] Here, the data used in the offline simulation of the method of the invention example was the same as the data used in the offline simulation of the method of the comparative example, i.e., various data including performance data obtained when a hot-dip galvanized steel sheet was actually manufactured, attribute data of the hot-dip galvanized steel sheet, target delivery temperature of the hot-dip galvanized steel sheet, and manufacturing sequence of the hot-dip galvanized steel sheet were the same between the method of the invention example and the method of the comparative example.

[0116] FIG. 6 is a diagram showing an example of the relationship (in arbitrary units) between the set values ​​of the outlet temperature and the blower rotation speed and between time. In Fig. 6, t1 is the time when the tip of the steel strip to be cooled (welded part WP) reaches the entry position, and t2 is the time when the tip of the steel strip to be cooled reaches the exit position. 6, graph 611 is a graph showing the outlet temperature in the example of the invention. Graph 612 is a graph showing the outlet temperature in the comparative example. Graph 613 is a graph showing the target outlet temperature. Graph 621 is a graph showing the set value of the blower rotation speed in the example of the invention. Graph 622 is a graph showing the set value of the blower rotation speed in the comparative example.

[0117] As shown in graph 622, in the comparative example, the set value of the blower rotation speed was suddenly lowered at time t1 when the tip of the steel strip to be cooled reached the entry position, and then the set value of the blower rotation speed was gradually increased by feedback control after time t2 when the tip of the steel strip to be cooled reached the exit position. In the comparative example, such a change in the set value of the blower rotation speed was reflected in the exit temperature. That is, in the comparative example, the feedforward control is started when the tip of the steel strip to be cooled passes the entry position. As shown in graph 612, even when the feedforward control is performed, the exit strip temperature continues to decrease with respect to the target exit temperature (see graphs 612 and 613 at times t1 to t2). Then, the target exit temperature (see graph 613) is changed as the tip of the steel strip to be cooled approaches the exit position, and when the tip of the steel strip to be cooled reaches the exit position (see time t2), feedback control is started so that the actual value of the exit temperature approaches the target exit temperature. When feedback control was performed to correct the error in the outlet temperature (difference from the target outlet temperature) that occurred in the feedforward control, the overshoot of the outlet temperature became large (see graph 612 after time t2). As a result, it took time for the outlet temperature to converge to the target outlet temperature (see the difference between graphs 612 and 613 after time t2). Note that this calculation example illustrates a case in which the target outlet temperature is changed when the leading end of the steel strip to be cooled passes a position a predetermined distance upstream of the outlet position, but this is not necessarily required. For example, the target outlet temperature may be changed when the leading end of the steel strip to be cooled passes the inlet position, or the target outlet temperature may be changed when the leading end of the steel strip to be cooled passes the outlet position.

[0118] In contrast, in the example of the invention, at time t1 when the front end of the steel strip to be cooled reaches the entry position, the outlet temperature at the inlet of each zone is predicted, and the set value of the blower rotation speed is calculated so that the predicted value approaches the target outlet temperature. Therefore, for example, the response delay of the outlet temperature in the upstream zone can be absorbed by the set value of the blower rotation speed in the downstream zone. Therefore, as shown in graph 621, compared to the comparative example (graph 622), it was possible to prevent the set value of the blower rotation speed from being lowered too much. As a result, as shown in graph 611, in the method of the example of the invention, the overshoot of the outlet temperature when the target outlet temperature is changed can be made smaller than in the comparative example, and the time until the outlet temperature converges to the target outlet temperature can be significantly shorter than in the comparative example (see the difference between graphs 611 and 613 after time t2 and the difference between graphs 612 and 613).

[0119] <Summary> As described above, in this embodiment, the processing device 180 calculates a predicted value of the outlet temperature of the steel strip part at a predetermined predicted position including the equipment midway position in the quenching furnace 111 based on the attribute data of the steel strip M and the performance data including the blower rotation speed, the inlet temperature, and the temperature of the cooling gas, and calculates the blower rotation speed R of a predetermined blower installed downstream of the predicted position among the blowers 141a to 141d based on the calculated predicted value of the outlet temperature and the target outlet temperature. Therefore, it is possible to calculate the blower rotation speed R at which the predicted value of the outlet temperature in the quenching furnace 111 becomes close to (or coincides with) the target outlet temperature. Therefore, it is possible to suppress the deviation of the outlet temperature from the target outlet temperature when the steel strip M to be cooled is switched, compared to, for example, the case where feedforward control based on the inlet temperature is performed or feedback control based on the performance value of the outlet temperature is performed. Therefore, it is possible to suppress the deterioration of the quality of the steel strip M and the decrease in yield.

[0120] Furthermore, in this embodiment, the processing device 180 calculates a predicted value of the outlet temperature of the steel strip portion located at a predetermined midway point in the equipment, which is a predetermined predicted position, using actual data obtained in an area in the quenching furnace 111 upstream of the midway point in the equipment. Therefore, the actual data in the quenching furnace 111 can be reflected in the predicted value of the outlet temperature. This makes it possible to further improve the calculation accuracy of the predicted value of the outlet temperature.

[0121] In this embodiment, the processing device 180 repeatedly calculates the predicted value of the outlet temperature of the steel strip portion and calculates the blower rotation speed R based on the predicted value of the outlet temperature and the target outlet temperature in a control cycle s. Therefore, the operation of the blower rotation speed R can be repeatedly performed in the control cycle s, and the blower rotation speed R can be adjusted at short time intervals.

[0122] Furthermore, in this embodiment, before the leading end of the steel strip M to be cooled reaches the delivery position, the processing device 180 calculates a predicted value of the delivery temperature of the steel strip portion located at a predetermined predicted position including an intermediate position in the equipment inside the quenching furnace 111. Therefore, before the leading end of the steel strip M to be cooled reaches the delivery position, control based on the predicted value of the delivery temperature and the target delivery temperature can be started.

[0123] In this embodiment, the processing device 180 calculates predicted values ​​of the outlet temperature of the steel strip portions located at a plurality of intermediate positions in the facility. Therefore, it is possible to calculate predicted values ​​of the outlet temperature at a plurality of positions in the quenching furnace 111. Therefore, it is possible to calculate the blower rotation speed R for supplying the cooling gas to a plurality of positions in the quenching furnace 111.

[0124] In this embodiment, the processing device 180 calculates a predicted value of the outlet temperature of a steel strip portion at a predetermined predicted position using a prediction formula including a physical model, which is a mathematical formula that at least calculates the temperature of the steel strip portion when the steel strip portion reaches the outlet position. Therefore, the predicted value of the outlet temperature of the steel strip portion can be calculated in accordance with physical phenomena in the steel strip M.

[0125] In addition, in this embodiment, the processor 180 calculates the predicted value of the outlet temperature using a prediction formula that further includes an error correction amount calculation formula for correcting errors in the physical model, thereby making it possible to further improve the accuracy of the prediction formula.

[0126] In this embodiment, the error correction amount calculation formula includes a correction amount for an error caused by metal strip transportation, which is an error caused by a change in the direction in which the cooling gas hits the steel strip M depending on the line speed and the speed (flow velocity) of the cooling gas. Therefore, it is possible to calculate the blower operation amount taking into account the error of the physical model (error caused by metal strip transportation).

[0127] In this embodiment, the processing device 180 includes a regression equation including a correction amount for the error of the physical model as an independent variable in the prediction equation, and calculates the regression coefficient of the regression equation by performing regression analysis. Therefore, even if the error correction amount calculation equation is not a complicated formula, it is possible to improve the calculation accuracy of the error correction amount e[t+d] of the physical model.

[0128] In this embodiment, the processor 180 calculates the blower rotation speed R of a specific blower that is installed downstream of the predicted position among the blowers 141a to 141d by performing a calculation to search for an optimal solution of the evaluation function J including the prediction error ΔT of the outlet temperature. Therefore, it is possible to quantitatively calculate the blower rotation speed that reduces the prediction error ΔT of the outlet temperature.

[0129] Furthermore, in this embodiment, the processing device 180 performs calculations to search for an optimal solution of the evaluation function J that further includes the blower rotation speed change amount ΔR. Therefore, it is possible to prevent the blower rotation speed R from being changed significantly, or to prevent the blower rotation speed R that cannot be realized by the blowers 141a to 141d from being calculated.

[0130] In this embodiment, the processing device 180 calculates a search range for an optimal solution of the evaluation function J based on the supply capacity of cooling gas by a predetermined blower installed downstream of the predicted position among the blowers 141a to 141d, and calculates the blower rotation speed R of the blower within the calculated search range. Therefore, it is possible to more reliably prevent the calculation of a blower rotation speed R that cannot be realized by the blowers 141a to 141d.

[0131] In addition, in this embodiment, the processor 180 calculates the optimal solution of the evaluation function J using a method that always calculates a solution if the solution exists within the search range of the solution. Therefore, it is possible to prevent the solution (the blower rotation speed change amount ΔR in this embodiment) from not being calculated.

[0132] Furthermore, in this embodiment, the processing device 180 selects a small search range that satisfies a predetermined necessary condition for the existence of an optimal solution (for example, the above (A)) from among a plurality of small search ranges obtained by dividing the search range for the optimal solution of the evaluation function J, calculates the optimal solution of the evaluation function J in the selected small search range as a candidate for the optimal solution of the evaluation function J in the search range for the optimal solution, and calculates the blower rotation speed R of a predetermined blower among the blowers 141a to 141d that is installed downstream of the predicted position based on the calculated candidate for the optimal solution of the evaluation function J. Therefore, even if the number of extreme values ​​of the evaluation function J is not determined within the search range for the optimal solution, it is possible to increase the probability that the optimal solution of the evaluation function J is calculated.

[0133] In this embodiment, the predetermined predicted positions include the positions of the boundaries between two adjacent zones (the inlets L2 to L4 of the second to fourth zones) in the quenching furnace 111. Therefore, the blower rotation speed R for supplying the cooling gas to each zone in the quenching furnace 111 can be calculated.

[0134] Furthermore, in this embodiment, the processing device 180 calculates the blower rotation speed R of the blower for cooling the steel strip portion in the downstream zone of two zones that share a predetermined predicted position as a boundary (for example, when the entrance L2 of the second zone is the predetermined predicted position, the blower 141b for cooling the steel strip portion in the second zone that is downstream of the first zone and the second zone). Therefore, cooling based on the calculation result of the blower rotation speed R can be performed quickly on the steel strip M.

[0135] <Modification> In the present embodiment, a case has been exemplified where a predicted value of the outlet temperature of the steel strip portion is calculated using a prediction equation including a physical model. However, the predicted value of the outlet temperature does not have to be calculated using a prediction equation including a physical model. For example, the processing device 180 may calculate a predicted value of the outlet temperature using a regression equation that does not include a physical model, in which the predicted value of the outlet temperature is a dependent variable and one or more influencing factors on the predicted value of the outlet temperature are independent variables. In addition, in the present embodiment, the cooling facility is exemplified as the quenching furnace 111 provided in the continuous annealing furnace 110 of the continuous hot-dip galvanizing line. However, the cooling facility is not limited to the quenching furnace 111 provided in the continuous annealing furnace 110 of the continuous hot-dip galvanizing line. For example, the method of the present embodiment may be applied to a cooling furnace provided in a continuous annealing furnace of a production line other than the continuous hot-dip galvanizing line.

[0136] The above-described embodiment of the present invention can be realized by a computer executing a program. A computer-readable recording medium having the program recorded thereon and a computer program product such as the program can also be applied as an embodiment of the present invention. Examples of the recording medium that can be used include a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a non-volatile memory card, and a ROM. The embodiment of the present invention can be realized by a PLC (Programmable Logic Controller) or dedicated hardware such as an ASIC (Application Specific Integrated Circuit). Furthermore, the above-described embodiments of the present invention are merely examples of the implementation of the present invention, and the technical scope of the present invention should not be interpreted as being limited by these. In other words, the present invention can be implemented in various forms without departing from its technical concept or main features.

[0137] <Disclosure> The disclosure of the above embodiment can be, for example, as follows. [Disclosure 1] A processing device for controlling a cooling facility that includes a plurality of cooling medium supply devices and continuously cools a plurality of metal strips that are connected to each other and transported on a transport path, the processing device comprising: a data acquiring unit that acquires data including attribute data indicating attributes of the metal strip, performance data including an operation amount for the cooling medium supply device, an inlet temperature of the metal strip, and a temperature of the cooling medium, and a target value of an outlet temperature corresponding to the metal strip; An operation amount calculation unit that calculates the operation amount, The operation amount calculation unit calculating a predicted value of an outlet temperature of a portion of the metal strip to be cooled that is located at a predetermined predicted position using the attribute data and the performance data; calculating the operation amount for a predetermined one of the cooling medium supply devices installed downstream of the predetermined predicted position based on the calculated predicted value of the outlet temperature and the target value of the outlet temperature corresponding to the metal strip; Do the following: The processing apparatus, wherein the predetermined predicted position includes a mid-facility position that is a position downstream of an inlet position of the cooling equipment and a position upstream of an outlet position of the cooling equipment. [Disclosure 2] The processing device according to Disclosure 1, wherein the operation amount calculation unit calculates a predicted value of the outlet temperature of the part located at a midpoint of the equipment, which is the specified predicted position, by using the performance data obtained in an area within the cooling equipment that is upstream of the midpoint of the equipment. [Disclosure 3] 3. The processing device according to claim 1, wherein the operation amount calculation unit repeats, for each time step, calculation of a predicted value of an outlet temperature of a part located at the predetermined prediction position and calculation of the operation amount based on the predicted value of the outlet temperature and a target value of the outlet temperature. [Disclosure 4] The processing apparatus according to any one of Disclosures 1 to 3, wherein the operation amount calculation unit calculates a predicted value of the outlet temperature of the part located at the predetermined predicted position before the leading end of the metal strip to be cooled reaches the outlet position. [Disclosure 5] The processing apparatus according to any one of Disclosures 1 to 4, wherein there are a plurality of intermediate positions of the equipment that are the predetermined predicted positions. [Disclosure 6] The processing apparatus according to any one of Disclosures 1 to 5, wherein a prediction formula used to calculate a predicted value of an outlet temperature of the part located at the predetermined predicted position includes a physical model, which is a formula for calculating at least a temperature of the part located at the predetermined predicted position when the part reaches the outlet position. [Disclosure 7] The processing device according to Disclosure 6, wherein the prediction formula further includes an error correction amount calculation formula for correcting an error in the temperature calculated by the physical model. [Disclosure 8] At least a correction amount for the metal strip transportation-induced error is calculated by the error correction amount calculation formula, The processing apparatus according to Disclosure 7, wherein the error due to metal strip transportation is an error caused by a change in the direction in which the cooling medium hits the metal strip depending on the transportation speed of the metal strip and the speed of the cooling medium. [Disclosure 9] a regression coefficient calculation unit that calculates a regression coefficient of a regression equation including an amount of correction for the error in the temperature calculated by the physical model as an independent variable; The prediction formula includes the regression formula, The data acquisition unit further acquires the outlet temperature as the performance data, 9. The processing device according to claim 7 or 8, wherein the regression coefficient calculation unit calculates the regression coefficients by performing a regression analysis using the performance data acquired by the data acquisition unit. [Disclosure 10] The processing device according to any one of Disclosures 1 to 9, wherein the operation amount calculation unit calculates an operation amount for the specified cooling medium supply device by performing a calculation to search for an optimal solution of an evaluation function including a first evaluation index that evaluates the difference between a predicted value of an outlet temperature of a part at the specified predicted position and a target value of the outlet temperature. [Disclosure 11] The processing apparatus according to Disclosure 10, wherein the evaluation function further includes a second evaluation index for evaluating a change amount of an operation amount for the predetermined cooling medium supply device. [Disclosure 12] The operation amount calculation unit Calculating a search range for an optimal solution of the evaluation function based on a supply capacity of the cooling medium in the predetermined cooling medium supply device; calculating a change amount of an operation amount for the cooling medium supply device within the calculated search range; The processing device according to Disclosure 10 or 11, [Disclosure 13] the operation amount calculation unit calculates an optimal solution of the evaluation function by performing a numerical analysis; 13. The processing device according to any one of Disclosures 10 to 12, wherein the method of the numerical analysis uses a method in which a solution is always calculated if a solution exists within a search range for the solution. [Disclosure 14] The operation amount calculation unit Calculating a search range for an optimal solution of the evaluation function based on a supply capacity of the cooling medium in the predetermined cooling medium supply device; selecting a sub-search range that satisfies a predetermined necessary condition for an optimal solution of the evaluation function to exist in the search range from among a plurality of sub-search ranges obtained by dividing the calculated search range; calculating an optimal solution of the evaluation function in the selected small search range by performing a numerical analysis; calculating an operation amount for the predetermined cooling medium supply device based on the calculated optimal solution of the evaluation function in the small search range; and The processing apparatus according to any one of Disclosures 10 to 13, [Disclosure 15] The cooling facility has a plurality of zones separated in a direction in which the metal strip is transported, The processing device according to any one of Disclosures 1 to 14, wherein the predetermined predicted position includes a position corresponding to a boundary between two of the zones that are adjacent to each other. [Disclosure 16] The processing apparatus of Disclosure 15, wherein the predetermined cooling medium supply device includes a cooling medium supply device for cooling the portion located in a downstream zone of the two zones that are separated by the predetermined predicted position. [Disclosure 17] A processing method for controlling a cooling facility that includes a plurality of cooling medium supply devices and that continuously cools a plurality of metal strips that are connected to each other and transported on a transport path, comprising: a data acquiring process for acquiring data including attribute data indicating attributes of the metal strip, performance data including an operation amount for the cooling medium supply device, an inlet temperature of the metal strip, and a temperature of the cooling medium, and a target value of an outlet temperature corresponding to the metal strip; and a manipulation amount calculation step of calculating the manipulation amount, The operation amount calculation step includes: calculating a predicted value of an outlet temperature of a portion of the metal strip to be cooled that is located at a predetermined predicted position using the attribute data and the performance data; calculating the operation amount for a predetermined one of the cooling medium supply devices installed downstream of the predetermined predicted position based on the calculated predicted value of the outlet temperature and the target value of the outlet temperature corresponding to the metal strip; Do the following: The processing method, wherein the predetermined predicted position includes an intermediate position of the cooling equipment that is a position downstream of an inlet position of the cooling equipment and a position upstream of an outlet position of the cooling equipment. [Disclosure 18] A program for causing a computer to function as each part of the processing device according to any one of Disclosures 1 to 16. [Explanation of symbols]

[0138] 110 Continuous annealing furnace 111 Quenching furnace 120 Plating tank 131 Inlet thermometer 132 Outlet thermometer 133a~133d Gas thermometer 134a~134d RPM measuring device 135 Line Speed ​​Measuring Instrument 141a~141d Blower 142a~142d Motor 143a~143d Inverter 151a~151i Transport roll 160 Sequencer 170 Management device 180 Processing Equipment 181 Data Acquisition Department 182 Operation amount calculation section 183 Output section 184 Regression coefficient calculation section 411-413 Blower speed change amount at which the evaluation function shows an extreme value 611 Graph showing outlet temperature in the invention example 612 Graph showing outlet temperature in comparative example 613 Graph showing target outlet temperature 621 Graph showing the setting value of the blower rotation speed in the invention example 622 Graph showing the setting value of the blower rotation speed in the comparative example a1~a3 Lower limit of blower speed change amount in small search range b1~b3 Upper limit of blower speed change amount in small search range L1~L4 Entrances to Zones 1~4 L5 Exit for Zone 4 M1~M4 Steel strip

Claims

1. A processing device for controlling a cooling facility that includes a plurality of cooling medium supply devices and continuously cools a plurality of metal strips that are connected to each other and transported on a transport path, the processing device comprising: a data acquiring unit that acquires data including attribute data indicating attributes of the metal strip, performance data including an operation amount for the cooling medium supply device, an inlet temperature of the metal strip, and a temperature of the cooling medium, and a target value of an outlet temperature corresponding to the metal strip; An operation amount calculation unit that calculates the operation amount, The operation amount calculation unit calculating a predicted value of an outlet temperature of a portion of the metal strip to be cooled that is located at a predetermined predicted position using the attribute data and the performance data; calculating the operation amount for a predetermined one of the cooling medium supply devices installed downstream of the predetermined predicted position based on the calculated predicted value of the outlet temperature and the target value of the outlet temperature corresponding to the metal strip; Do the following: The processing apparatus, wherein the predetermined predicted position includes a mid-facility position that is a position downstream of an inlet position of the cooling equipment and a position upstream of an outlet position of the cooling equipment.

2. 2. The processing device according to claim 1, wherein the operation amount calculation unit calculates a predicted value of the outlet temperature of the part located at the equipment midway position, which is the specified predicted position, by using the performance data obtained in an area within the cooling equipment that is upstream of the equipment midway position.

3. 3. The processing device according to claim 1, wherein the operation amount calculation unit repeats, for each time step, a calculation of a predicted value of an outlet temperature of the part located at the predetermined prediction position, and a calculation of the operation amount based on the predicted value of the outlet temperature and a target value of the outlet temperature.

4. The processing apparatus according to claim 1 , wherein the operation amount calculation unit calculates a predicted value of the outlet temperature of the part located at the predetermined predicted position before a leading end of the metal strip to be cooled reaches the outlet position.

5. The processing apparatus according to claim 1 or 2, wherein the predetermined predicted position is a plurality of intermediate positions in the facility.

6. 3. The processing apparatus according to claim 1, wherein a prediction formula used to calculate a predicted value of an outlet temperature of the part at the predetermined predicted position includes a physical model that is a mathematical formula for at least calculating a temperature of the part at the predetermined predicted position when the part reaches the outlet position.

7. The processing apparatus according to claim 6 , wherein the prediction formula further includes an error correction amount calculation formula for correcting an error in the temperature calculated by the physical model.

8. At least a correction amount for the metal strip transportation-induced error is calculated by the error correction amount calculation formula, The processing apparatus according to claim 7 , wherein the error due to metal strip transportation is an error caused by a change in the direction in which the cooling medium hits the metal strip depending on a transportation speed of the metal strip and a speed of the cooling medium.

9. a regression coefficient calculation unit that calculates a regression coefficient of a regression equation including an amount of correction for the error in the temperature calculated by the physical model as an independent variable; The prediction formula includes the regression formula, The data acquisition unit further acquires the outlet temperature as the performance data, The processing device according to claim 7 , wherein the regression coefficient calculation unit calculates the regression coefficients by performing a regression analysis using the performance data acquired by the data acquisition unit.

10. 3. The processing device according to claim 1, wherein the operation amount calculation unit calculates the operation amount for the predetermined cooling medium supply device by performing a calculation to search for an optimal solution of an evaluation function including a first evaluation index that evaluates a difference between a predicted value of an outlet temperature of a part located at the predetermined predicted position and a target value of the outlet temperature.

11. The processing apparatus according to claim 10 , wherein the evaluation function further includes a second evaluation index for evaluating a change amount of an operation amount for the predetermined cooling medium supply device.

12. The operation amount calculation unit Calculating a search range for an optimal solution of the evaluation function based on a supply capacity of the cooling medium in the predetermined cooling medium supply device; calculating a change amount of an operation amount for the cooling medium supply device within the calculated search range; The processing device according to claim 10, further comprising:

13. the operation amount calculation unit calculates an optimal solution of the evaluation function by performing a numerical analysis; The processing device according to claim 10 , wherein the numerical analysis method uses a method in which a solution is always calculated if a solution exists within a search range for the solution.

14. The operation amount calculation unit Calculating a search range for an optimal solution of the evaluation function based on a supply capacity of the cooling medium in the predetermined cooling medium supply device; selecting a sub-search range that satisfies a predetermined necessary condition for an optimal solution of the evaluation function to exist in the search range from among a plurality of sub-search ranges obtained by dividing the calculated search range; calculating an optimal solution of the evaluation function in the selected small search range by performing a numerical analysis; calculating an operation amount for the predetermined cooling medium supply device based on the calculated optimal solution of the evaluation function in the small search range; and The processing device according to claim 10, further comprising:

15. The cooling facility has a plurality of zones separated in a direction in which the metal strip is transported, The processing device according to claim 1 or 2, wherein the predetermined predicted positions include positions corresponding to boundaries of two of the zones adjacent to each other.

16. The processing apparatus according to claim 15 , wherein the predetermined cooling medium supply device includes a cooling medium supply device for cooling the portion in a downstream zone of the two zones having the predetermined predicted position as a boundary.

17. A processing method for controlling a cooling facility that includes a plurality of cooling medium supply devices and that continuously cools a plurality of metal strips that are connected to each other and transported on a transport path, comprising: a data acquiring process for acquiring data including attribute data indicating attributes of the metal strip, performance data including an operation amount for the cooling medium supply device, an inlet temperature of the metal strip, and a temperature of the cooling medium, and a target value of an outlet temperature corresponding to the metal strip; and a manipulation amount calculation step of calculating the manipulation amount, The operation amount calculation step includes: calculating a predicted value of an outlet temperature of a portion of the metal strip to be cooled that is located at a predetermined predicted position using the attribute data and the performance data; calculating the operation amount for a predetermined one of the cooling medium supply devices installed downstream of the predetermined predicted position based on the calculated predicted value of the outlet temperature and the target value of the outlet temperature corresponding to the metal strip; Do the following: The processing method, wherein the predetermined predicted position includes an intermediate position of the cooling equipment that is a position downstream of an inlet position of the cooling equipment and upstream of an outlet position of the cooling equipment.

18. A program for causing a computer to function as each unit of the processing device according to claim 1 or 2.

Images