Looper control device, looper control method, and program

Abstract

To suppress discrepancy between an actual value and a command value of tensile force of a belt-like body if the command value of the tensile force of the belt-like body is changed when a looper carriage remains stationery in a loop storage device comprising the looper carriage.SOLUTION: A looper controller 110 calculates a control input after static friction compensation for giving an external force exceeding a maximum static frictional force F0 to a looper carriage 206 as a control input for controlling tensile force of a steel strip S if a plate tensile force set value is changed when the looper carriage 206 remains stationery.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a looper control device, a looper control method, and a program, and is particularly suitable for use in controlling the operation of a loop storage device. [Background technology]

[0002] In a continuous processing line that continuously processes strip-shaped materials such as steel strips (strip-shaped steel plates), the trailing end of a preceding strip and the leading end of a following strip are transported connected. When processing strips in a continuous processing line, it may be necessary to temporarily reduce or stop the transport speed of the strips. For example, when connecting the trailing end of a preceding strip to the leading end of a following strip, or when cutting the trailing end of a preceding strip, it is necessary to temporarily reduce or stop the transport speed of the strips. In such cases, a loop storage device is installed in the continuous processing line so that the strips can be processed continuously without changing the transport speed. The loop storage device temporarily stores strips transported from processes upstream of the loop storage device, and discharges the temporarily stored strips to processes downstream of the loop storage device. In the loop storage device, the direction of travel of the strips is changed by a roll. By adjusting the length of the strip whose direction of travel is changed in this way by changing the position of the roll, the length of the strips temporarily stored in the loop storage device is adjusted.

[0003] Loop storage devices are equipped with looper trolleys (also known as loop cars, etc.) to change the position of the rolls. The position of the rolls is changed by moving the looper trolley from a predetermined position. This predetermined position is called the synchronous position.

[0004] In such loop storage devices, fluctuations in the tension of the strip may affect processing in the continuous processing line. For example, if the actual tension of the strip is lower than the commanded value, the strip may meander in its width direction. This may result in defects in the shape of the strip, and in some cases, serious operational problems such as the breakage of the strip or damage to equipment such as the loop storage device may occur. Therefore, as a technique for controlling the tension of the strip in a loop storage device, Patent Document 1 describes compensating for mechanical losses in the upstream section of the loop storage device in accordance with changes in the line speed of the continuous processing line when controlling the tension of the strip in the loop storage device. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2-160116 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the technology described in Patent Document 1 does not consider the tension of the strip-shaped material in the loop storage device when the looper trolley is stationary. Therefore, even if the command value for the tension of the strip-shaped material increases when the looper trolley is stationary, the actual value of the tension of the strip-shaped material may deviate from the command value because the looper trolley does not move. Consequently, as mentioned above, problems arise due to the strip-shaped material meandering in its width direction.

[0007] The present invention has been made in view of the above-mentioned problems, and aims to suppress the discrepancy between the actual tension value and the command value of the tension of the strip-shaped body when the command value of the tension of the strip-shaped body is changed while the looper trolley is stationary in a loop storage device equipped with a looper trolley. [Means for solving the problem]

[0008] The looper control device of the present invention controls the tension of a strip of material in a loop storage device that temporarily stores a strip of material transported from an upstream process facility and discharges it to a downstream process facility, using a looper trolley that moves along a transport path to adjust the amount of the strip of material stored. The device includes an operation amount calculation unit that calculates an operation amount for controlling the tension, and when the tension setting value, which is the set value of the tension, is changed while the looper trolley is stationary, the operation amount calculation unit calculates a static friction-compensated operation amount to apply an external force to the looper trolley that exceeds the maximum static friction force between the looper trolley and the transport path, as the operation amount for controlling the tension.

[0009] The present invention relates to a looper control device for controlling the tension of a strip of material in a loop storage device that temporarily stores a strip of material transported from an upstream process facility and discharges it to a downstream process facility, using a looper trolley that moves along a transport path to adjust the amount of the stored strip of material. The device includes an operation amount calculation step for calculating an operation amount for controlling the tension, wherein when the tension setting value, which is the set value of the tension, is changed while the looper trolley is stationary, the operation amount calculation step calculates a static friction-compensated operation amount for applying an external force to the looper trolley that exceeds the maximum static friction force between the looper trolley and the transport path, as the operation amount for controlling the tension.

[0010] The program of the present invention causes a computer to function as one of the components of the looper control device. [Effects of the Invention]

[0011] According to the present invention, in a loop storage device equipped with a looper trolley, when the command value for the tension of the strip-shaped body is changed while the looper trolley is stationary, it is possible to suppress the discrepancy between the actual tension value of the strip-shaped body and the command value. [Brief explanation of the drawing]

[0012] [Figure 1] This figure shows an example of the configuration of a continuous hot-dip galvanizing line. [Figure 2] It is a schematic diagram showing an example of the configuration of the inlet side looper. [Figure 3] It is a diagram showing an example of the configuration of a pulley, a wire, and a drum provided in the looper carriage. [Figure 4A] It is a diagram conceptually showing an example of the relationship between the looper carriage position (position of the looper carriage) and the synchronization position and time. [Figure 4B] It is a diagram conceptually showing an example of the relationship between the plate tension (tension of the steel strip S stored in the inlet side looper) and the drum torque (torque of the looper motor) and time. [Figure 5A] It is a diagram conceptually showing an example of the force generated when starting the movement of a stationary looper carriage. [Figure 5B] It is a diagram conceptually showing an example of the relationship between the frictional force and the external force when |Fdrum| < |Fplate| and F2 > F1. [Figure 5C] It is a diagram conceptually showing an example of the relationship between the frictional force and the external force when |Fdrum| < |Fplate| and F2 < F1. [Figure 5D] It is a diagram conceptually showing an example of the relationship between the frictional force and the external force when |Fdrum| > |Fplate| and F2 > F1. [Figure 5E] It is a diagram conceptually showing an example of the relationship between the frictional force and the external force when |Fdrum| > |Fplate| and F2 < F1. [Figure 6] It is a diagram showing an example of the functional configuration of the looper control device. [Figure 7A] It is a diagram conceptually showing the first example (example when α = 1) of the relationship between the plate tension, the drum torque, and the carriage speed and time in the first embodiment. [Figure 7B] It is a diagram conceptually showing the second example (example when α = 0.5) of the relationship between the plate tension, the drum torque, and the carriage speed and time in the first embodiment. [Figure 7C] It is a diagram conceptually showing the third example (example when α = 0) of the relationship between the plate tension, the drum torque, and the carriage speed and time in the first embodiment. [Figure 8] This is a flowchart illustrating an example of a loop control method in the first embodiment. [Figure 9] This diagram conceptually illustrates an example of the relationship between plate tension, drum torque, and trolley speed and time in the second embodiment. [Figure 10-1] This is a flowchart illustrating an example of a loop control method in the second embodiment. [Figure 10-2] This is a flowchart following Figure 10-1. [Modes for carrying out the invention]

[0013] Embodiments of the present invention will be described below with reference to the drawings. Furthermore, the term "same" in terms of length, position, size, spacing, etc., includes not only cases where the items are exactly the same, but also cases where they differ to the extent that they do not deviate from the spirit of the invention (for example, differences within the tolerance range defined at the time of design).

[0014] (Continuous processing line) In the embodiments of the present invention described later, an example is given of applying a loop storage device to a continuous processing line (hereinafter, the loop storage device will be referred to as a looper). In a continuous processing line, multiple strips are processed continuously by connecting the trailing end of a preceding strip to the leading end of a following strip. In the embodiments of the present invention described later, a continuous hot-dip galvanizing line is given as an example of such a continuous processing line. Figure 1 is a diagram showing an example of the configuration of a continuous hot-dip galvanizing line, which is an example of applying a loop storage device in the embodiments of the present invention described later. In Figure 1, a steel strip S, which is an example of a strip, is transported in the positive direction of the y-axis, and the width direction of the steel strip S is in the x-axis direction.

[0015] In Figure 1, a cold-rolled coil produced in the cold-rolling process is attached to the payoff reel 101. The steel strip S unwound from the cold-rolled coil attached to the payoff reel 101 is supplied to the production line. When the supply of the cold-rolled coil attached to the payoff reel 101a to the production line is completed, the supply of the cold-rolled coil attached to the payoff reel 101b to the production line is performed. In other words, the cold-rolled coils attached to the payoff reels 101a and 101b are supplied to the production line alternately.

[0016] The steel strip S unwound from the cold-rolled coil is transported to the welding equipment 102. The welding equipment 102 welds the leading end of the steel strip S unwound from the cold-rolled coil to the trailing end of a steel strip S that has been transported prior to it. Here, a continuous hot-dip galvanizing line is used as an example of a continuous processing line, and the example shows the steel strip S unwound from the cold-rolled coil as a strip-shaped body. However, the strip-shaped body is not limited to steel strip S unwound from a cold-rolled coil. For example, the strip-shaped body may be steel strip S unwound from a hot-rolled coil.

[0017] The steel strip S joined with the preceding steel strip S in the welding equipment 102 is transported to the entry looper 103. Here, the section from the payoff reel 101 to the entry looper 103 is called the entry section (first section). The entry looper 103 temporarily stores the steel strip S transported from the welding equipment 102, which is an example of the equipment in the upstream process, and discharges it to the annealing furnace 104, which is an example of the equipment in the downstream process. The annealing furnace 104 continuously anneals the steel strip S.

[0018] When welding the trailing end of a preceding steel strip S to the leading end of a following steel strip S using the welding equipment 102, it is necessary to temporarily stop the transport of these steel strips S. In such cases, the entry looper 103 discharges the steel strips S to the annealing furnace 104 while reducing the amount of steel strip S it has accumulated. By doing so, the steel strips S can be processed continuously without reducing the transport speed of the steel strips S in the processes downstream from the entry looper 103 (such as the annealing furnace 104).

[0019] The plating equipment 105 continuously applies a plating treatment, such as hot-dip galvanizing, to the surface of the steel strip S that has been continuously annealed in the annealing furnace 104. The temper rolling mill 106 temper-rolls the steel strip S that has been plated in the plating equipment 105. Here, the section from the annealing furnace 104 to the temper rolling mill 106 is called the central section (second section).

[0020] The steel strip S, which has been temper-rolled in the temper-rolling mill 106, is transported to the exit looper 107. The exit looper 107 temporarily stores the steel strip S transported from the temper-rolling mill 106, which is an example of upstream equipment, and discharges it to the cutting equipment 108, which is an example of downstream equipment. The tension reel 109 winds the steel strip S into a plated coil. When winding the steel strip S onto tension reel 109a is completed, winding the steel strip S onto tension reel 109b is performed. That is, winding the steel strip S onto tension reels 109a and 109b is performed alternately. The cutting equipment 108 is installed between the exit looper 107 and the tension reel 109. When the amount (length) of steel strip S wound onto tension reel 109 reaches a predetermined amount, the cutting equipment 108 cuts the steel strip S in the width direction (x-axis direction). Here, the section from the exit looper 107 to the tension reel 109 is referred to as the exit section (third section).

[0021] When cutting the steel strip S with the cutting equipment 108, it is necessary to temporarily stop the transport of the steel strip S. In such cases, the exit looper 107 increases the amount of steel strip S it has stored while discharging the steel strip S to the cutting equipment 108. By doing so, the steel strip S can be processed continuously without reducing the transport speed of the steel strip S in the process upstream of the exit looper 107 (central section).

[0022] It should be noted that the continuous hot-dip galvanizing line itself can be realized using known technologies and is not limited to the example shown in Figure 1. In addition, the continuous hot-dip galvanizing line may also be equipped with equipment that is present in known continuous hot-dip galvanizing lines, in addition to the equipment shown in Figure 1. The continuous hot-dip galvanizing line is equipped with various types of rolls, not shown, such as conveying rolls for transporting steel strips S.

[0023] In Figure 1, the looper control device 110 is a device that controls the operation of the input looper 103 and the output looper 107. The entry looper 103 and the exit looper 107 have the same configuration. As mentioned above, the entry looper 103 reduces the amount of steel strip S stored when the transport speed of the steel strip S is reduced to zero in the upstream equipment, and discharges the steel strip S to the downstream equipment. In contrast, the exit looper 107 reduces the amount of steel strip S stored when the transport speed of the steel strip S is reduced to zero in the downstream equipment, and discharges the steel strip S to the downstream equipment while increasing the amount of steel strip S stored. Therefore, the explanation of the exit looper 107 will be based on the explanation of the entry looper 103, with the following substitutions: First, the upstream equipment (welding equipment 102) will be replaced with the downstream equipment (cutting equipment 108). Also, the transport speed of the steel strip S upstream of the entry looper 103 (negative direction of the y-axis) will be replaced with the transport speed of the steel strip S downstream of the exit looper 107. Furthermore, when stopping the transport of steel strip S for operation in the upstream equipment (welding equipment 102), the operation of reducing the amount of steel strip S stored in the inlet looper 103 is replaced with the operation of increasing the amount of steel strip S stored in the outlet looper 107 when stopping the transport of steel strip S for operation in the downstream equipment (cutting equipment 108). For the reasons described above, the inlet looper 103 will be used as an example in the following explanation, and a detailed explanation of the outlet looper 107 will be omitted. In addition to the looper control device 110, the continuous hot-dip galvanizing line is also equipped with a control device (not shown) that controls the continuous hot-dip galvanizing line. Since this control device (not shown) can be implemented using known technology, a detailed explanation is omitted here.

[0024] (Loop storage device (inlet looper 103)) Figure 2 is a schematic diagram showing an example of the configuration of the entry-side looper 103. The looper control device 110 is also shown in Figure 2. In Figure 2, the symbols (>, <) attached to the steel strip S indicate the conveying direction of the steel strip S, and indicate that the steel strip S is conveyed in the direction toward the tip of the symbol. In Figure 2, the entry-side looper 103 includes an entry-side roll motor 201 (201a~201b), an entry-side bridle roll 202 (202a~202b), a looper roll 203 (203a~203h), a central-side roll motor 204 (204a~204b), a central-side bridle roll 205 (205a~205b), a looper trolley 206, a looper motor 207, a rail 208, a tension sensor 209, a speed sensor 210, and a torque sensor 211.

[0025] The entry-side roll motors 201a to 201b are motors for rotating the entry-side bridle rolls 202a to 202b, and rotate according to the control of a speed control device (not shown). The rotational speed of the entry-side roll motors 201a to 201b determines the transport speed of the steel strip S upstream of the entry-side looper 103 (negative direction of the y-axis). In the following description, the transport speed of the steel strip S upstream of the entry-side looper 103 (negative direction of the y-axis) will be referred to as the entry-side speed. In this embodiment, the entry-side roll motors 201a to 201b are three-phase AC motors. However, the entry-side roll motors 201a to 201b are not limited to three-phase AC motors, and may be AC ​​motors other than three-phase, or DC motors.

[0026] The entry-side bridle rolls 202a to 202b are drive rolls that rotate in conjunction with the rotation of the entry-side roll motors 201a to 201b. The entry-side speed is determined based on the rotational speed of the entry-side bridle rolls 202a to 202b. In addition, the entry-side bridle rolls 202a to 202b change the direction of travel of the steel strip S.

[0027] The looper rolls 203a to 203h are undriven rolls (rolls not driven by a motor) used to change the direction of travel of the steel strip S temporarily stored in the entry-side looper 103. In the embodiments of the present invention described later, the case in which the entry-side looper 103 is a so-called horizontal looper is illustrated. A horizontal looper is a looper configured such that the steel strip S is transported such that the angle between the direction of movement of the looper trolley 206 (the direction of extension of the rail 208) and the direction of gravity acting on the steel strip S is approximately 90°. Therefore, the looper rolls 203a to 203h are arranged such that, when viewed from the width direction (x-axis direction) of the steel strip S, the direction of travel of the steel strip S in the direction of movement of the looper trolley 206 (y-axis direction) alternates. In addition, while the looper rolls 203a to 203e do not move, the looper rolls 203f to 203h are attached to the looper trolley 206 and move along with the movement of the looper trolley 206. Each portion of the steel plate S that is folded back by the looper rolls 203f to 203h attached to the looper trolley 206 (each portion of the steel plate S whose length changes in the direction of movement of the looper trolley 206 (y-axis direction) as the looper trolley 206 moves) is called a strand. In the example shown in Figure 2, there are 6 strands. In addition, a tension detector 209 is attached to the looper roll 203c to detect the tension applied to the steel strip S stored in the entry looper 103.

[0028] Furthermore, the position in which the tension detector 209 is attached is not limited to the looper rolls 203a to 203h (louver roll 203c in Figure 2) inside the entry looper 103, as long as it is a position in which the tension of the steel strip S being transported inside or near the entry looper 103 can be detected.

[0029] Furthermore, in the following, the tension applied to the steel strip S temporarily stored in the entry looper 103 will be referred to as plate tension as necessary, the actual value of said plate tension will be referred to as the actual plate tension value as necessary, and the target value (command value) of said plate tension will be referred to as the command plate tension value as necessary. Here, the tension detected by the tension detector 209 is the tension in one strand. Therefore, the tension of the steel strip S temporarily stored in the entry looper 103 is the value obtained by multiplying the tension detected by the tension detector 209 by the number of strands (6 in the example shown in Figure 2). In each embodiment of the present invention described later, the actual plate tension value is the value obtained by multiplying the tension detected by the tension detector 209 by the number of strands, and an example is given in which such an actual plate tension value is calculated by the tension detector 209 and output to the looper control device 110. Note that the looper control device 110 may also calculate the actual plate tension value based on the tension detected by the tension detector 209.

[0030] The central roll motors 204a to 204b rotate according to the control of a speed control device (not shown). The rotational speed of the central roll motors 204a to 204b determines the conveying speed of the steel strip S in the central section. In the following description, the conveying speed of the steel strip S in the central section will be referred to as the central speed. The central speed is determined according to the capacity and condition of the equipment in the central section (annealing furnace 104, plating equipment 105, temper rolling mill 106), etc. In each embodiment of the present invention described later, the central roll motors 204a to 204b are three-phase AC motors. However, the central roll motors 204a to 204b are not limited to three-phase AC motors, and may be AC ​​motors other than three-phase or DC motors.

[0031] The central bridle rolls 205a to 205b are drive rolls that rotate in conjunction with the rotation of the central roll motors 204a to 204b. The central speed is determined based on the rotational speed of the central bridle rolls 205a to 205b. In addition, the direction of travel of the steel strip S is changed by the central bridle rolls 205a to 205b.

[0032] The looper trolley 206 moves along a rail 208, which is an example of a movement path. In the embodiments of the present invention described later, the rail 208 is laid along the installation surface (floor surface) of the continuous hot-dip galvanizing line. As mentioned above, in the embodiments of the present invention described later, the case in which the entry-side looper 103 is a so-called horizontal looper is illustrated, and the case in which the angle between the extension direction of the rail 208 (the direction of movement of the looper trolley 206) and the direction of gravity acting on the steel strip S is approximately 90° is illustrated. Specifically, the case in which the looper trolley 206 moves in the y-axis direction and the steel strip S is subjected to gravity in the negative z-axis direction is illustrated. As mentioned above, the looper rolls 203f to 203h are attached to the looper trolley 206. Therefore, the looper rolls 203f to 203h move in the y-axis direction as the looper trolley 206 moves.

[0033] In Figure 2, the positive direction of the y-axis is called the storage side, and the negative direction of the y-axis is called the discharge side. As shown in Figure 2, in each embodiment of the present invention described later, the position of the looper trolley 206 in the y-axis direction when the looper trolley 206 is located on the most negative direction side of the y-axis (discharge side) is set as the origin 0, and the position of the looper trolley 206 in the y-axis direction is defined accordingly. Therefore, the value of the position of the looper trolley 206 in the y-axis direction is 0 or greater. When the looper trolley 206 moves to the positive direction side of the y-axis (storage side), the amount of steel strip S stored in the input looper 103 increases. On the other hand, when the looper trolley 206 moves to the negative direction side of the y-axis (discharge side), the amount of steel strip S stored in the input looper 103 decreases. Here, the position of the looper trolley 206 in the y-axis direction is, for example, the position in the y-axis direction of the center of gravity of the looper trolley 206. In the following explanation, the position of the looper trolley 206 in the y-axis direction will simply be referred to as the position of the looper trolley 206.

[0034] During the period when the entry speed and the center speed are the same (the period during which the entry speed is not changed in order to perform welding at the welding equipment 102), the looper trolley 206 is at the synchronized position L s The position of the looper bogie 206 is controlled to be at position L (however, the position of the looper bogie 206 is controlled by the tension of the steel strip S described later to the synchronous position L s(It may move from here). In Figure 2, the synchronized position of the looper trolley 206 is L s This is how it is written. Synchronization position L of looper trolley 206 s For example, based on the assumed time for stopping the steel strip S at the position of welding equipment 102 in order to perform welding at welding equipment 102, and the assumed speed as the central speed, the amount of steel strip S discharged from the entry looper 103 while the steel strip S is stopped at the position of welding equipment 102 is set in advance so as not to be insufficient. The looper trolley 206 is at the synchronous position L s When it moves towards the positive direction of the y-axis (storage side), the steel strip S is stored in the entry-side looper 103. Meanwhile, when the looper trolley 206 moves to the synchronous position L s When moving further towards the negative direction of the y-axis (discharge side), the steel strip S stored in the inlet looper 103 is discharged to the central section (annealing furnace 104).

[0035] In Figure 2, the looper trolley 206 comprises a pulley 212, a wire 213, a drum 214, and a trolley body 215. The trolley body 215 has wheels 215a positioned on the rail 208, and a frame 215b that supports the pulley 212 and the looper rolls 203f~203h, etc. A looper motor 207 is attached to the drum 214. The looper motor 207 is a motor for rotating the drum 214. In the embodiments of the present invention described later, the looper motor 207 is a three-phase AC motor. The looper motor 207 is not limited to a three-phase AC motor, and may be an AC motor other than a three-phase motor, or a DC motor.

[0036] The drum 214 rotates in conjunction with the rotation of the looper motor 207. The looper motor 207 is equipped with a speed sensor 210 for detecting the rotational speed of the looper motor 207 and a torque sensor 211 for detecting the torque of the looper motor 207. As the drum 214 rotates, the wire 213 is wound onto the drum 214 and unwound from the drum 214. Here, the torque of the looper motor 207 corresponds to the torque of the drum 214. Therefore, in the following explanation, the torque of the looper motor 207 will be referred to as drum torque as needed.

[0037] Figure 3 shows an example of the configuration of the pulley 212, wire 213, and drum 214 of the looper trolley 206. Figure 3 is a view of the looper trolley 206 shown in Figure 2 from above (along the z axis). Here, we illustrate the movable pulley type looper trolley 206 shown in Figure 3(a) and the fixed pulley type looper trolley 206 shown in Figure 3(b).

[0038] The movable pulley 212a shown in Figure 3(a) is attached to the chassis body 215 of the looper chassis 206 so as to be rotatable. The axis of rotation of the movable pulley 212a is approximately parallel to the z-axis. The extension direction of the wire 213 reverses at the position of the movable pulley 212a. One end of the wire 213 is fixed to a fixed end 216 that is in a fixed position and does not move. The other end of the wire 213 is attached to the drum 214a. In the example shown in Figure 3(a), the axis of rotation of the looper motor 207 and the axis of rotation of the drum 214a are approximately parallel to the x-axis. As the looper motor 207 rotates, the drum 214a and the movable pulley 212a rotate, changing the amount of wire 213 wound on the drum 214a. A reduction gear may be installed between the looper motor 207 and the drum 214a.

[0039] The fixed pulley 212b shown in Figure 3(b) is attached to the body of the looper trolley 206. The fixed pulley 212b does not rotate. The extension direction of the wire 213 reverses at the position of the fixed pulley 212b, and one end and the other end of the wire 213 are attached to the drum 214b. In the example shown in Figure 3(b), the rotation axis of the looper motor 207 and the rotation axis of the drum 214b are approximately parallel to the x-axis. As the looper motor 207 rotates, the drum 214b rotates, changing the amount of wire 213 wound on the drum 214b. A reduction gear (gear) may be installed between the looper motor 207 and the drum 214b. The looper trolley 206 may be either a movable pulley type as shown in Figure 3(a) or a fixed pulley type as shown in Figure 3(b).

[0040] (Insights) Here, we will explain the findings of the present inventors. Figure 4A is a conceptual diagram showing an example of the relationship between the looper trolley position (position of the looper trolley 206), the synchronization position, and time. Figure 4B is a conceptual diagram showing an example of the relationship between the plate tension (tension of the steel strip S stored in the entry-side looper 103), the drum torque (torque of the looper motor 207), and time. In the graph of Figure 4A, the position 411 of the looper trolley 206 is shown by a solid line, and the synchronization position 412 is shown by a dashed line.

[0041] At time t1, the entry speed is reduced (deceleration) to perform welding at the welding equipment 102, and the looper trolley 206 moves to the synchronous position 412 (synchronous position L s Time t2 is the time when movement from the input side to the discharge side (negative direction of the y-axis) begins.Time t2 is the time when welding at the welding equipment 102 is finished and the input speed is increased (acceleration) begins.Time t3 is the time when the looper trolley 206 begins to move to the storage side (positive direction of the y-axis).Time t4 is the time when the input speed 401 becomes the same as the central speed 402 and the position 411 of the looper trolley 206 is at the synchronized position 412 (L s It is time to return to ).

[0042] In the example shown in FIG. 4A, during the period when the input-side speed is not changed to perform welding with the welding equipment 102 (the period before time t1 and the period after time t4), the input-side speed and the central speed are the same, and the position 411 of the looper carriage 206 is the synchronization position L s and is fixed. That is, during the period before time t1 and the period after time t4, the looper carriage 206 is stationary.

[0043] On the other hand, during the period when the input-side speed is changed to perform welding with the welding equipment 102 (the period from time t1 to time t4), the input-side speed and the central speed are different, and the looper carriage 206 moves. Specifically, during the period from time t1 to time t3, the input-side speed is slower than the central speed, and the looper carriage 206 moves toward the pay-out side (the negative direction side of the y-axis in FIG. 2). On the other hand, during the period from time t3 to time t4, the input-side speed is faster than the central speed, and the looper carriage 206 moves toward the storage side (the positive direction side of the y-axis in FIG. 2).

[0044] As shown in the position 411 of the looper carriage 206 in FIG. 4A, the present inventors found that during the period when the input-side speed is not changed to perform welding with the welding equipment 102 (the period before time t1 and the period after time t4), the looper carriage 206 is at the synchronization position L s and is stationary. As shown in FIG. 4B, even if the strip tension command value 421 is increased and the drum torque actual value 422, which is the torque of the looper motor 207 detected by the torque detector 211, increases, the strip tension actual value 423 does not increase, and the deviation between the strip tension actual value 423 and the strip tension command value 421 becomes large. That is, when the looper carriage 206 remains stationary, the strip tension actual value does not follow the change in the strip tension command value, and the control accuracy of the tension of the steel strip S decreases. As described in the section of the problem to be solved by the invention, if the tension of the steel strip S (the strip tension actual value) is lower than the strip tension command value, the steel strip S may meander in its width direction. Then, there is a possibility that a defect in the shape of the steel strip S may occur, and in some cases, serious operation troubles such as breakage of the steel strip S or damage to equipment such as the loop storage device may occur.

[0045] Figures 5A to 5E illustrate the reason for the discrepancy between the commanded plate tension value 421 and the actual plate tension value 423. Figure 5A conceptually shows an example of the forces generated when a stationary looper trolley 206 begins to move. Figures 5B to 5E conceptually show an example of the relationship between frictional force and external force.

[0046] Figure 5A illustrates the case where a stationary looper trolley 206 begins to move toward the storage side (positive direction of the y-axis). In this case, an external force acts on the looper trolley 206 toward the discharge side (negative direction of the y-axis) based on the tension (plate tension) of the steel strip S (plate tension F is shown beside Figure 5A). plate (See the white arrow line indicated as such). Also, an external force based on the drum tension, which is the tension of the wire 213 generated by the torque (drum torque) of the looper motor 207, acts on the storage side of the looper trolley 206 (Drum tension F is shown next to Figure 5A). drum (See the white arrow indicated as such). In addition to these external forces, a static friction force is generated on the discharge side of the stationary looper bogie 206 between the looper bogie 206 and the rail 208 (see the white arrow indicated as static friction force F0' next to Figure 5A).

[0047] As shown in Figures 5B to 5E, an external force (F) exceeding the maximum static friction force F0 between the object and the contact surface of the object is applied. N Unless an external force exceeding (F) is applied, an object will not be subjected to an external force (e.g., external force F). L Even if a force is applied, the object will not move. Therefore, in order to move the stationary looper trolley 206 to the storage side, the static friction force F0' between the looper trolley 206 and the rail 208 must be compensated with a friction force having an absolute value greater than the absolute value of the difference between the maximum static friction force F0 between the looper trolley 206 and the rail 208 (=|F0-F0'|). Otherwise, even if the plate tension command value 421 is increased, the actual plate tension value 423 will not increase. For this reason, as shown in Figure 4B, the plate tension command value 421 and the actual plate tension value 423 diverge.

[0048] The static frictional force F0' between the looper carriage 206 and the rail 208 is the value obtained by subtracting the absolute value of the external force based on the plate tension (plate tension F drum ) from the absolute value of the external force based on the drum torque (drum tension F plate ) (F0' = |F drum | - |F plate |). Here, the static frictional force F0' between the looper carriage 206 and the rail 208 is assumed to have a negative value when acting in the direction of the storage side (the positive direction side of the y-axis). For example, when the looper carriage 206 is in a stationary state, if the balance relationship between the drum tension F drum and the plate tension F plate is |F drum | < |F plate |, the static frictional force F0' between the looper carriage 206 and the rail 208 acts in the opposite direction (storage side) to the external force based on the plate tension (plate tension F plate ), so it becomes a negative value.

[0049] Here, let the plate tension setting value before the change be F1 (N), and the plate tension setting value after the change be F2 (N). FIG. 5B is a diagram showing an example of the relationship between the frictional force and the external force when the balance relationship between the drum tension F drum and the plate tension F plate is |F drum | < |F plate | and the plate tension setting value increases (F2 > F1). FIG. 5C is a diagram showing an example of the relationship between the frictional force and the external force when the balance relationship between the drum tension F drum and the plate tension F plate is |F drum | < |F plate | and the plate tension setting value decreases (F2 < F1). FIG. 图解5D is a diagram showing an example of the relationship between the frictional force and the external force when the balance relationship between the drum tension F drum and the plate tension F plate is |F drum | > |F plate | and the plate tension setting value increases (F2 > F1). FIG. 5E is a diagram showing an example of the relationship between the frictional force and the external force when the looper carriage 206 is in a stationary state and the drum tension Fdrum and the sheet tension F plate The balance relationship of |F drum | > |F plate |, and it is a diagram showing an example of the relationship between the frictional force and the external force when the sheet tension set value decreases (when F2 < F1).

[0050] As shown in FIGS. 5B to 5E, in the loop storage device (inlet loop 103) including the looper carriage 206, in order to move the stationary looper carriage 206, a large external force exceeding the maximum static frictional force F0 between the looper carriage 206 and the rail 208 must be applied to the looper carriage 206. That is, the absolute value of the difference between the maximum static frictional force F0 between the looper carriage 206 and the rail 208 and the static frictional force F0' between the looper carriage 206 and the rail २०८ (= |F0 - F0'| = |F comp |), the static frictional force F0' between the looper carriage 206 and the rail 208 must be compensated with a frictional force having an absolute value larger than that. For example, when the looper carriage 206 increases in size in order to increase the storage amount of the steel strip S in the loop storage device or to cope with the allocation of the installation space between the loop storage device and its peripheral equipment, the mass of the looper carriage 206 increases. Then, the maximum static frictional force F0 between the looper carriage 206 and the rail 208 increases, and the influence of the maximum static frictional force F0 becomes large.

[0051] Therefore, the inventors considered compensating the static frictional force F0' between the looper carriage 206 and the rail 208 so that an external force exceeding the maximum static frictional force F0 between the looper carriage 206 and the rail 208 is applied to the looper carriage 206 when the change in the tension of the steel strip S is instructed while the looper carriage 206 is stationary at the synchronization position L s Then, when the change in the tension of the steel strip S is instructed while the looper carriage 206 is stationary at the synchronization position L, the static frictional force F0' between the looper carriage 206 and the rail 208 is compensated so that an external force exceeding the maximum static frictional force F0 between the looper carriage 206 and the rail 208 is applied to the looper carriage 206.

[0052] An example of a looper control device 110 for controlling the tension of the steel strip S temporarily stored in the entry-side looper 103 is described below. In the following description, the steel strip S temporarily stored in the entry-side looper 103 will be simply referred to as the steel strip S, as needed. Also, the maximum static friction force F0 between the looper trolley 206 and the rail 208 will be simply referred to as the maximum static friction force F0, as needed.

[0053] In the explanation of Figure 5A, when the steel strip S is stopped at the position of the welding equipment 102 in the entry-side looper 103, the looper trolley 206 is set to the synchronized position L for dispensing the steel strip S to the central section. s It moves from there. On the other hand, in the exit looper 107, when the steel strip S is stopped at the position of the cutting equipment 108, the looper trolley 206 moves to the synchronized position L in order to store the steel strip S in the exit looper 107. s Move from here. Taking this into consideration, the explanation of the input looper 103 described above, referring to Figures 4A, 4B, and 5A to 5E, becomes an explanation of the output looper 107. Therefore, the same idea can be derived for the output looper 107 as for the input looper 103. Each of the following embodiments of the present invention is based on the ideas described in this section (the <Knowledge> section).

[0054] (First Embodiment) First, a first embodiment of the present invention will be described. <Looper control device 110> The looper control device 110 of this embodiment will now be described. In this embodiment, the functions and processing of the looper control device 110 will be illustrated using the entry looper 103 as an example of a loop storage device. However, as mentioned above, when controlling the exit looper 107, in the following description of the looper control device 110, the welding equipment 102 will be replaced with the cutting equipment 108, the entry speed will be replaced with the exit speed (the transport speed of the steel strip S downstream of the exit looper 107), and the operation of reducing the amount of steel strip S stored in the entry looper 103 when the transport of steel strip S is stopped for operation at the welding equipment 102 will be replaced with the operation of increasing the amount of steel strip S stored in the exit looper 107 when the transport of steel strip S is stopped for operation at the cutting equipment 108. Therefore, a detailed explanation of the looper control device 110 when controlling the exit looper 107 will be omitted.

[0055] Furthermore, in this embodiment, the control performed by the looper control device 110 will be mainly described in terms of the control of the tension of the steel strip S, but the looper control device 110 may also perform other controls besides the control of the tension of the steel strip S. For example, the looper control device 110 may also control the position of the looper trolley 206. For example, the looper control device 110 outputs an entry speed command value, which is the command value of the entry speed, to a speed control device (not shown) that controls the rotational speed of the entry roll motors 201a to 201b. As a result, an excitation current that results in a rotational speed corresponding to the entry speed command value flows to the stator coils of the entry roll motors 201a to 201b, causing the entry roll motors 201a to 201b to rotate and changing the position of the looper trolley 206. In this embodiment, as described with reference to Figure 4A, the entry speed is changed to perform welding in the welding equipment 102, and the position of the looper trolley 206 is controlled during the period when the entry speed and the center speed are different (from time t1 to time t4). When the entry speed and the center speed become the same (at time t1 or time t4), the position of the looper trolley 206 is set to the synchronous position L s This illustrates the case where the looper trolley 206 comes to a standstill. In this way, by controlling the position of the looper trolley 206, the position of the looper trolley 206 is set to the synchronous position L. sThis is the case. However, in this embodiment, the looper trolley 206 is in the synchronous position L s When the train is stationary, if a change in the tension of the steel strip S is instructed, the tension of the steel strip S is controlled to temporarily move the looper trolley 206, thereby suppressing the discrepancy between the aforementioned plate tension command value 421 and the actual plate tension value 423.

[0056] Furthermore, this embodiment illustrates a case in which the looper control device 110 repeatedly controls the tension of the steel strip S at a constant control cycle by operating the looper motor 207. Also, this embodiment illustrates a case in which the amount operated by the looper control device 110 when controlling the tension of the steel strip S is the torque of the looper motor 207. Therefore, the looper control device 110 controls the looper motor 207 by calculating the torque of the looper motor 207 that cancels out the deviation between the command value (plate tension command value) and the actual value (actual plate tension value) of the tension of the steel strip S, and by generating an excitation current that generates the calculated torque and outputting it to the looper motor 207.

[0057] The hardware of the looper control device 110 can be implemented, for example, by using an information processing device equipped with a processing unit (e.g., a central processing unit), a storage device (e.g., a main memory and an auxiliary storage device), and various interface devices, or by using dedicated hardware.

[0058] Figure 6 shows an example of the functional configuration of the looper control device 110. The operational performance acquisition unit 601 acquires operational performance values ​​in the continuous hot-dip galvanizing line. For example, the operational performance acquisition unit 601 acquires the tension applied to the steel strip S detected by the tension detector 209 (actual plate tension value), the rotational speed of the looper motor 207 detected by the speed detector 210, and the torque of the looper motor 207 detected by the torque detector 211 (actual drum torque value).

[0059] The rotational speed of the looper motor 207 corresponds to the travel speed of the looper trolley 206. The travel speed of the looper trolley 206 is calculated, for example, based on the rotational speed (rpm) of the looper motor 207, the gear ratio (-) of the looper motor 207, the outer diameter D (m) of the drum 214b, and the type of pulley (movable pulley or fixed pulley). For example, the travel speed (mpm) of the looper trolley 206 is calculated by motor rotational speed × (1 / gear ratio) × πD / C, where C(-) is a variable that is 1 for a fixed pulley and 2 for a movable pulley. Also, parentheses indicate the unit of each symbol, and (-) indicates a dimensionless quantity (this is also true for other notations). In the following, the moving speed of the looper trolley 206 will be referred to as the trolley speed, as needed, and the moving speed of the looper trolley 206 based on the rotational speed of the looper motor 207 detected by the speed detector 210 will be referred to as the actual trolley speed, as needed.

[0060] The operational setting value acquisition unit 602 acquires operational commands for the continuous hot-dip galvanizing line. In this embodiment, an example is given in which the operational setting value acquisition unit 602 acquires operational commands for the continuous hot-dip galvanizing line from an external device, the line management computer 620. The line management computer 620 is a computer that manages operations in the continuous hot-dip galvanizing line. For example, the operational setting value acquisition unit 602 acquires the set value of tension applied to the steel strip S temporarily stored in the entry-side looper 103. In the following description, the set value of tension applied to the steel strip S temporarily stored in the entry-side looper 103 will be referred to as the plate tension set value as needed. The operational setting value acquisition unit 602 may acquire setting values ​​other than the plate tension set value. For example, the operational setting value acquisition unit 602 may acquire the central speed set value and the entry-side speed set value in order to control the position of the looper trolley 206.

[0061] The communication method between the looper control device 110 and the line management computer 620 may be either wired or wireless. Furthermore, the looper control device 110 may be included within the line management computer 620. Also, at least one of the operation commands (such as plate tension settings) in the continuous hot-dip galvanizing line may be set manually by the operator, for example. In this case, the operation setting acquisition unit 602 acquires the operation command set by the operator, for example, using the user interface of the looper control device 110.

[0062] The tension command calculation unit 603 calculates the target value (plate tension command value) of the tension applied to the steel strip S temporarily stored in the entry looper 103 at each time (each control cycle) based on the plate tension setting value acquired by the operation setting value acquisition unit 602. The plate tension setting value is the final target value of the steel strip S, and is the target value when the tension of the steel strip S is in a steady state. On the other hand, the plate tension command value is the target value of the tension of the steel strip S at each time (each control cycle), and also includes the target value during the process of the tension of the steel strip S becoming steady.

[0063] The tension command calculation unit 603 may, for example, change the plate tension command value to the changed plate tension setting value all at once when the plate tension setting value is changed. However, from the viewpoint of achieving stable control, in this embodiment, the tension command calculation unit 603 repeatedly adds a certain plate tension to the plate tension command value before the change in each control cycle until the cumulative value of the added plate tension reaches the changed plate tension setting value (time t in Figures 7A to 7C described later). a ~t b(See board tension command value 721 in [reference]). For example, if the board tension setting value before the change is F1 (N), the board tension setting value after the change is F2 (N), and the rate of change per unit time is a (N / s), then the board tension command value 1 s after the start of changing the board tension command value is F1 + a (N), and the time required for the board tension setting value to change from F1 to F2 is (F2 - F1) ÷ a (s). Here, in the following explanation, the board tension setting value before the change will be denoted as F1 as necessary, and the board tension setting value after the change will be denoted as F2 as necessary. Note that in the following explanation, after the board tension setting value has been changed from F1 to F2, the changed board tension setting value F2 will become F1, and any subsequent board tension setting values ​​will be F2.

[0064] The manipulated amount calculation unit 600 calculates the manipulated amount used by the looper control device 110 to control the tension of the steel strip S based on various actual values, set values, and command values ​​(actual plate tension value, actual trolley speed value, actual drum torque value, plate tension set value, and plate tension command value). As described above, in this embodiment, the case in which the manipulated amount used by the looper control device 110 to control the tension of the steel strip S is the torque of the looper motor 207 is illustrated. In this embodiment, when the plate tension set value is changed while the looper trolley 206 is stationary, the manipulated amount calculation unit 600 calculates the manipulated amount after static friction compensation as the manipulated amount for controlling the tension of the steel strip S. Here, the manipulated amount after static friction compensation is the manipulated amount calculated as the manipulated amount for controlling the tension of the steel strip S in order to apply an external force exceeding the maximum static friction force F0 to the looper trolley 206.

[0065] In this embodiment, the manipulated variable calculation unit 600 is exemplified as having a tension deviation calculation unit 604, a PI control unit 605, a tension addition unit 606, a torque conversion unit 607, a static friction compensation amount calculation unit 608, a static friction compensation amount correction unit 609, a mechanical loss compensation unit 610, a mechanical loss compensation amount correction unit 611, an inertia compensation unit 612, an inertia compensation amount correction unit 613, and a command unit 614. An example of the function of each unit is calculated below.

[0066] The tension deviation calculation unit 604 calculates the deviation of the tension applied to the steel strip S temporarily stored in the entry-side looper 103 from the actual plate tension value to the plate tension command value. In the following description, the deviation of the tension applied to the steel strip S stored in the entry-side looper 103 from the actual plate tension value to the plate tension command value is called the plate tension deviation. In this embodiment, the tension deviation calculation unit 604 calculates the plate tension deviation by subtracting the actual plate tension value from the plate tension command value.

[0067] The PI control unit 605 performs PI control and calculates a tension change amount, which is the amount of tension change that cancels out the plate tension deviation. The discrepancy between the actual plate tension value 423 and the plate tension command value 421, as explained with reference to Figure 4B, can be suppressed by increasing the control gain of the PI control unit 605. However, doing so may cause the actual plate tension value to hunt (vibrate), potentially reducing the accuracy of tension control of the steel strip S. Therefore, it is preferable that the control gain in the PI control unit 605 be set to suppress hunting of the actual plate tension value (preferably to be 0 (zero)).

[0068] The tension addition unit 606 calculates a tension that cancels out the plate tension deviation by adding the plate tension command value and the tension change amount. The torque conversion unit 607 converts the tension calculated by the tension addition unit 606 into torque. For example, the torque conversion unit 607 has a pre-stored relationship formula between the torque of the looper motor 207 and the tension of the steel strip S temporarily stored in the input looper 103, and uses this relationship formula to convert the tension calculated by the tension addition unit 606 into torque. Alternatively, a lookup table may be used instead of the relationship formula. In the following explanation, the torque converted by the torque conversion unit 607 is used as a reference torque T as needed. R It is called that.

[0069] The static friction compensation unit 608 compensates for the static friction force F0' between the looper bogie 206 and the rail 208 when the plate tension setting value is changed while the looper bogie 206 is stationary, by setting a static friction compensation amount T. comp Calculate the static friction compensation amount T.comp This is a compensation amount that makes the external force applied to the looper trolley 206 greater than before the plate tension setting value was changed. In this way, the static friction compensation unit 608 compensates for the static friction force F0' between the looper trolley 206 and the rail 208 by setting an external force that exceeds the maximum static friction force F0 on the looper trolley 206. This compensation amount is the static friction compensation amount T. comp The calculation is performed as follows: The controllable amount for controlling the tension of the steel strip S is the static friction compensation amount T. comp It is modified based on the above. As mentioned above, in this embodiment, the case in which the manipulated amount for controlling the tension of the steel strip S is the torque (drum torque) of the looper motor 207 is illustrated.

[0070] In this embodiment, an example is given in which the static friction compensation unit 608 includes a tension setting change determination unit 608a, a trolley speed determination unit 608b, a static friction force calculation unit 608c, and a static friction compensation amount calculation unit 608d.

[0071] The tension setting change determination unit 608a determines whether the plate tension setting value has been changed (from F1 to F2) based on the plate tension setting value acquired by the operation setting value acquisition unit 602. When the tension setting change determination unit 608a determines that the plate tension setting value has been changed, the trolley speed determination unit 608b determines whether the trolley speed value acquired by the operation performance acquisition unit 601 is 0 (zero) or not (i.e., whether the looper trolley 206 is stationary or not).

[0072] The static friction force calculation unit 608c calculates the static friction force F0' generated between the looper bogie 206 and the rail 208 against the external force applied to the looper bogie 206 in the current control cycle. Below, with reference to Figures 5A to 5E, an example of a method for calculating the static friction force F0' generated between the looper bogie 206 and the rail 208 against the external force applied to the looper bogie 206 in the current control cycle will be described. In the following description, the static friction force F0' generated between the looper bogie 206 and the rail 208 against the external force applied to the looper bogie 206 in the current control cycle will be referred to as the current static friction force F0' as needed.

[0073] In Figures 5B to 5E, the external force applied to the looper trolley 206 in the current control cycle is F. L Let's assume this is the case. This external force F L The static friction force generated between the looper bogie 206 and the rail 208 against this force is the current static friction force F0'. As explained in the <Knowledge> section with reference to Figures 5A to 5E, the static friction force F0' between the looper trolley 206 and the rail 208 is an external force based on drum torque (drum tension F drum From the absolute value of ), the external force based on the plate tension (plate tension F) plate (F0'=|F drum |-|F plate |).

[0074] Therefore, in this embodiment, the static friction force calculation unit 608c calculates the drum tension F in the current control cycle. drum The absolute value of (N) and the plate tension F in the current control period. plate The difference between the absolute value of (N) and is calculated as the current static friction force F0'(N). That is, the static friction force calculation unit 608c calculates the current static friction force F0'(N) using the following equation (1). Note that drum tension F drum This corresponds to the external force generated on the looper trolley 206 by an operation (drum torque in this embodiment) to control the tension of the steel strip S. F0'=|F drum |-|F plate | ···(1)

[0075] Here, the drum tension F in the current control cycle. drum (N) is the actual drum torque value T for the current control cycle, obtained by the operational performance acquisition unit 601. drum Based on (N·m), the radius r(m) of the drum 214b, and the gear ratio (-) of the looper motor 207, it can be expressed by the following equation (2). F drum =T drum ÷{r × (1 / gear ratio)} ... (2) Note that the actual drum torque value T in the current control cycle is also shown. drum Instead, the drum torque command value T in the current control cycle drum You may also use this. Furthermore, in equation (1), the plate tension F in the current control cycle. plate This is the actual plate tension value for the current control cycle, obtained by the operational performance acquisition unit 601 (= tension detected by the tension detector 209 × number of strands).

[0076] Next, an example of the timing at which the static friction force calculation unit 608c calculates the current static friction force F0' using equation (1) as described above will be explained. In this embodiment, the static friction force calculation unit 608c calculates the current static friction force F0' using equation (1) when the tension setting change determination unit 608a determines that the plate tension setting value has been changed (from F1 to F2), and the bogie speed determination unit 608b determines that the actual bogie speed value is 0 (zero).

[0077] From the viewpoint of accelerating the timing of compensating for the static friction force F0' between the looper trolley 206 and the rail 208, it is preferable to calculate the current static friction force F0' as early as possible when the plate tension setting value is changed while the looper trolley 206 is stationary. On the other hand, if the timing of compensating for the static friction force F0' between the looper trolley 206 and the rail 208 is made too early, there is a risk that the looper trolley 206 will stop before the actual plate tension value 423 reaches the plate tension command value 421. In this case, there is a risk that the discrepancy between the actual plate tension value 423 and the plate tension command value 421 cannot be sufficiently reduced.

[0078] Therefore, in this embodiment, the static friction force calculation unit 608c calculates a plate tension reference value Fs, which is the value obtained by dividing the plate tension setting value F1 before the change and the plate tension setting value F2 after the change by a predetermined internal division ratio, and calculates the current static friction force F0' using equation (1) when the plate tension command value in the current control cycle becomes the plate tension reference value Fs.

[0079] The standard plate tension value Fs(N) is calculated, for example, by the following equation (3), where the internal division ratio parameter α(-), which indicates the internal division ratio as described above, is set to a value between 0 and 1. Fs = F1 + (F2 - F1) × α ... (3)

[0080] Figures 7A to 7C conceptually illustrate an example of the relationship between plate tension, drum torque, and trolley speed and time. Figure 7A shows the relationship when the internal division ratio parameter α is 1 (α=1), Figure 7B shows the relationship when the internal division ratio parameter α is 0.5 (α=0.5), and Figure 7C shows the relationship when the internal division ratio parameter α is 0 (α=0). In Figure 7, for the sake of simplicity, the compensation by the mechanical loss compensation amount correction unit 611 and the inertia compensation amount correction unit 613 is assumed to be 0 (zero). Note that the time t shown in Figures 7A to 7C a ~t e This indicates the time that arrives in the control cycle of the looper control device 110 (the so-called control time).

[0081] In Figures 7A to 7C, time t a This is the time when the plate tension setting value 711 is changed from F1 to F2. In this embodiment, time t a However, this is just one example of when the board tension setting value was changed. time t b This is the time when the plate tension command value 721 becomes the plate tension setting value 711 after the plate tension setting value 711 is changed from F1 to F2. In this embodiment, time t b However, this is just one example of when the tension command value becomes the changed tension setting value.

[0082] time t c This indicates the time at which the current static friction force F0' is calculated using equation (1). As will be explained in detail later, in this embodiment, time t c (1) The current static friction force F0' calculated by equation (1) is used to calculate the static friction compensation amount T calculated by the static friction compensation unit 608 (static friction compensation amount calculation unit 608d). comp This is the time when compensation begins.

[0083] time td is the time when the actual drum torque values 731 to 733 first reach the drum torque command values 741 to 743, which are the target values of the drum torque at each time (each control cycle), after the compensation for the static friction force F0' starts. Although details will be described later, in this embodiment, the time t d is the time when the compensation of the current static friction force F0' calculated by Equation (1) with the static friction compensation amount T comp calculated by the static friction compensation unit 608 is completed. Also, the drum torque command values 741 to 743 are used when generating the excitation current flowing through the looper motor 207 in the command unit 614 described later (see FIG. 2).

[0084] In this embodiment, the actual drum torque values 731 to 733 are an example of the actual values of the operation amount for controlling the tension. Also, the drum torque command values 741 to 743 are an example of the operation amount command values, which are the target values of the operation amount for controlling the tension. Also, the time t d is an example of the timing when the actual value of the operation amount for controlling the tension becomes the operation amount command value, which is the target value of the operation amount for controlling the tension.

[0085] The time t e is the time when the actual sheet tension values 751 to 753 first reach the changed sheet tension set value 711 (sheet tension command value 721). In this embodiment, the time t e is an example of the timing when the actual value of the tension becomes the set value of the tension after the change.

[0086] After the compensation for the static friction force F0' starts, when the actual drum torque values 731 to 733 become the drum torque command values 741 to 743 (that is, when it reaches the time t d ), the actual carriage speed values 761 to 763 exceed 0 (zero) (that is, the looper carriage 206 starts to move). Also, in this embodiment, the compensation of the current static friction force F0' calculated by Equation (1) with the static friction compensation amount T comp calculated by the static friction compensation unit 608 is completed at the time t d is the time t when the actual sheet tension values 751 to 753 become the sheet tension command value 721 eIt becomes the previous time, and the compensation is performed before the sheet tension actual values 751 to 753 reach the changed sheet tension set value 711 (= F2).

[0087] As shown in FIG. 7A, when the internal division ratio parameter α is 1 (α = 1), the time t for calculating the current static friction force F0' by the formula (1) c is the time t when the sheet tension command value 721 becomes the sheet tension set value 711 b is. In this way, compared with the case where the internal division ratio parameter α is less than 1, the current static friction force F0' calculated by the formula (1) is the static friction compensation amount T calculated by the static friction compensation unit 608 comp The timing (time t c ) to start compensating by is delayed.

[0088] On the other hand, as shown in FIGS. 7B and 7C, the closer the internal division ratio parameter α is to 0 (zero), the current static friction force F0' calculated by the formula (1) is the static friction compensation amount T calculated by the static friction compensation unit 608 comp The timing (time t c ) to start compensating by is earlier.

[0089] However, in this embodiment, the time t when the drum torque actual values 731 to 733 become the drum torque command values 741 to 743 after the compensation of the static friction force F0' starts d At, the current static friction force F0' calculated by the formula (1) is the static friction compensation amount T calculated by the static friction compensation unit 608 comp To end compensating by. And when the difference between the changed sheet tension set value F2 and the previous sheet tension set value F1 is large, the time t when the sheet tension command value 721 becomes the sheet tension set value 71 b Becomes late. Therefore, in this case, the time t when the drum torque actual values 731 to 733 become the drum torque command values 741 to 743 after the compensation of the static friction force F0' starts d (That is, the time when the looper carriage 206 starts to move) is greatly delayed, and the sheet tension command value 721 becomes the changed sheet tension set value 711 (= F2) (that is, time t b(This is the result). Also, as is clear from comparing Figures 7A to 7C, when the difference between the changed plate tension setting value F2 and the original plate tension setting value F1 is the same, the closer the internal division ratio parameter α is to 0 (zero), the better the time t d More than time b This process is delayed. Therefore, if the difference between the changed board tension setting value F2 and the original board tension setting value F1 is large, the closer the internal division ratio parameter α is to 0 (zero), the longer the time t when the actual board tension value 752 reaches the board tension command value 721. e Before that happens, there is a high probability that the actual trolley speed value of 761-763 will return to 0 (zero).

[0090] From the above viewpoint, it is preferable to set the internal ratio parameter α such that the actual bogie speed value 761-763 does not return to 0 (zero) before the actual plate tension value 751-753 reaches the plate tension command value 721-723. Therefore, it is preferable to set the internal ratio parameter α such that the actual bogie speed value 761-763 does not return to 0 (zero) before the actual plate tension value 752 reaches the plate tension command value 721, based on, for example, the range assumed to be the plate tension set value. The internal ratio parameter α may be a constant value, or it may be a variable value.

[0091] When the internal ratio parameter α is a variable value, the current static friction force F0' calculated by equation (1) is used in the range where the actual bogie speed value 761-763 does not return to 0 (zero) before the actual plate tension value 751-753 reaches the plate tension command value 721-723, and the static friction compensation amount T calculated by the static friction compensation unit 608 is used. comp The timing at which compensation begins (time t) c It is preferable to set the parameters such that the result is as fast as possible. In this case, for each case where the original plate tension setting value F2 and the original plate tension setting value F1 are different, the internal division ratio parameter α that satisfies the condition may be investigated, and based on the results of the investigation, a relationship that satisfies the condition may be found as the relationship between the difference between the original plate tension setting value F2 and the original plate tension setting value F1 and the internal division ratio parameter α. This relationship may be expressed as a lookup table or as a relational expression.

[0092] The static friction force calculation unit 608c stores, for example, information on the internal division ratio parameter α determined as described above (a fixed value if it is a fixed value, or a lookup table or relational expression if it is a variable value).

[0093] As described above, in this embodiment, the static friction force calculation unit 608c calculates the plate tension reference value Fs using equation (3), and at the timing (time t) when the plate tension command value 721 in the current control cycle becomes the plate tension reference value Fs c The current static friction force F0' is calculated using equation (1) in ).

[0094] Furthermore, the static friction force calculation unit 608c calculates the time of the current control cycle as the time t when the tension setting value was changed. a And the time t when the tension command value becomes the changed tension set value. b And, the time t that divides it internally by a predetermined internal division ratio. c In this case, the current static friction force F0' can be calculated using equation (1). If this is done, for example, instead of equation (3), the following equation (4) can be used to calculate time t c Calculate. t c =t a +(t b -t a ) × α ···(4)

[0095] Note that equations (3) and (4) are given at time t a From time t b The difference lies in whether the internal division point of the line representing the plate tension command value 721 during the period is calculated along the vertical axis (plate tension axis) or along the horizontal axis (time axis). Therefore, in equation (4), the internal division point parameter α may be a constant value from the aforementioned perspective, or it may be a value corresponding to the difference between the plate tension setting value F2 before the change and the plate tension setting value F1 before the change. Thus, the internal division ratio parameter α (a predetermined internal division ratio) only needs to be determined before the calculation to determine the plate tension reference value Fs begins.

[0096] Returning to the explanation of Figure 6, the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T based on the maximum static friction force F0 between the looper trolley 206 and the rail 208 and the current static friction force F0' calculated by the static friction force calculation unit 608c. comp Calculate.

[0097] As explained with reference to Figures 5A to 5E, it is necessary to compensate for the static friction force F0' between the looper bogie 206 and the rail 208 with a friction force having an absolute value greater than the absolute value of the difference (=|F0-F0'|) between the maximum static friction force F0 between the looper bogie 206 and the rail 208 and the static friction force F0' between the looper bogie 206 and the rail 208.

[0098] As shown in Figures 5B and 5D, when the plate tension setting increases (F2 > F1), the looper trolley 206 is moved towards the storage side (positive direction of the y-axis), and the maximum static friction force F0 that opposes this movement occurs on the discharge side (negative direction of the y-axis). As mentioned above, the maximum static friction force F0 has a negative value when acting in the direction of the storage side (positive direction of the y-axis), and has a positive value when acting in the direction of the discharge side (F0 > 0). In this case, the static friction force correction amount F is the friction force required to compensate the current static friction force F0' so that the static friction force F0' between the looper trolley 206 and the rail 208 becomes the maximum static friction force F0. comp (N) is given by equation (5a) below. F comp =F0-F0' ···(5a)

[0099] As shown in Figure 5B, the drum tension F when the looper trolley 206 is stationary. drum and board tension F plate The equilibrium relationship is |F drum |<|F plate If |, then from equation (1), the current static friction force F0' in equation (5a) is negative (F0'<0) and acts on the storage side (positive direction of the y-axis). On the other hand, as shown in Figure 5D, the drum tension F when the looper trolley 206 is stationary. drum and board tension F plateThe balance relationship is |F drum | > |F plate |, in this case, from equation (1), the current static friction force F0' in equation (5a) is positive (F0' > 0) and acts on the payout side (the negative direction side of the y-axis).

[0100] On the other hand, as shown in FIGS. 5C and 5E, when the sheet tension set value decreases (F2 < F1), the looper carriage 206 will move to the payout side (the negative direction side of the y-axis). Therefore, the maximum static friction force F0 that resists this occurs on the storage side (the positive direction side of the y-axis). As described above, the maximum static friction force F0 has a negative value (F0 < 0) when acting in the direction of the storage side (the positive direction side of the y-axis). In this case, the static friction force correction amount F comp (N) required to obtain the external force necessary to compensate the current static friction force F0' so that the static friction force F0' between the looper carriage 206 and the rail 208 becomes the maximum static friction force F0 is as follows in equation (5b). F comp = -F0 - F0' ···(5b)

[0101] As shown in FIG. 5C, when the looper carriage 206 is in a stationary state, the drum tension F drum and the sheet tension F plate The balance relationship is |F drum | < |F plate |, in this case, from equation (1), the current static friction force F0' in equation (5b) is negative (F0' < 0) and acts on the storage side (the positive direction side of the y-axis). On the other hand, as shown in FIG. 5E, when the looper carriage 206 is in a stationary state, the drum tension F drum and the sheet tension F plate The balance relationship is |F drum | > |F plate |, in this case, from equation (1), the current static friction force F0' in equation (5b) is positive (F0' > 0) and acts on the payout side (the negative direction side of the y-axis).

[0102] Here, the maximum static friction force F0 (N) between the looper carriage 206 and the rail 208 is based on the static friction coefficient μ (-) between the looper carriage 206 and the rail 208, the mass m (kg) of the looper carriage 206, and the gravitational acceleration g (m / s 2 ), and is expressed by the following equation (6). F0 = μ × m × g ···(6)

[0103] In equation (6), the static friction coefficient μ between the looper carriage 206 and the rail 208 and the mass m of the looper carriage 206 can be obtained from the specifications (design values) of the looper carriage 206. Therefore, the maximum static friction force F0 can be calculated in advance. Thus, the static friction compensation amount calculation unit 608d stores in advance the maximum static friction force F0 calculated by equation (6). The mass m of the looper carriage 206 may be determined in consideration of the mass of the steel strip S conveyed by the looper rolls 203f to 203h of the looper carriage 206.

[0104] Alternatively, the external force applied to the looper carriage 206 on the rail 208 may be gradually increased, and the external force at the timing when the looper carriage 206 starts to move may be obtained as the maximum static friction force F0. The static friction compensation amount calculation unit 608d may store in advance the maximum static friction force F0 obtained in this way.

[0105] Based on the maximum static friction force F0 obtained as described above and the current static friction force F0', the static friction compensation amount calculation unit 608d calculates the static friction force correction amount F comp by equation (5a) or (5b). When the sheet tension set value increases (F2 > F1), the static friction compensation amount calculation unit 608d calculates the static friction force correction amount F comp by equation (5a), and when the sheet tension set value decreases (F2 < F1), the static friction compensation amount calculation unit calculates the static friction force correction amount F comp by equation (5b). Note that when the sheet tension set value (F2 = F1) does not change, the static friction compensation amount calculation unit 608d does not necessarily need to calculate the static friction force correction amount F comp (the static friction force correction amount F comp may be set to 0 (zero)).

[0106] Then, the static friction compensation amount calculation unit 608d calculates the static friction force correction amount F comp Based on (N), the radius r (m) of the drum 214b, and the gear ratio (-) of the looper motor 207, the static friction force correction amount F is calculated by the following equation (7). comp The value converted to torque is the torque correction amount T'. comp It is calculated as (N·m). T' comp =F comp ×r × (1 / gear ratio) ... (7)

[0107] Then, the static friction compensation amount calculation unit 608d uses a coefficient β having a value greater than 1 and a torque correction amount T'. comp Based on the above, the static friction compensation amount T is calculated using equation (8) below. comp Calculate. T comp =T' comp ×β ···(8)

[0108] Note that the coefficient β may be 1 (i.e., the coefficient β may be a value greater than or equal to 1). However, if the coefficient β is 1, then the left and right sides of equations (5a) and (5b) become equal (F0 = F comp +F0' or F0=-F comp -F0'). This may make it impossible to reliably move the looper trolley 206. Therefore, in this embodiment, a value greater than 1 is adopted as the coefficient β so that the looper trolley 206 can be reliably moved. Increasing the coefficient β increases the amount of movement of the looper trolley 206. If the coefficient β approaches 1, the looper trolley 206 may not move depending on the condition of the wheels of the looper trolley 206 and the rail 208. The coefficient β is predetermined from this perspective, and the static friction compensation amount calculation unit 608d stores the coefficient β predetermined in advance. By using a value greater than 1 as the coefficient β in this way, the static friction force between the looper trolley 206 and the rail 208 is compensated by a friction force having an absolute value greater than the absolute value of the difference between the maximum static friction force F0 and the current static friction force F0', and the static friction compensation amount T comp This is calculated.

[0109] The static friction compensation amount calculation unit 608d calculates the static friction compensation amount T if the static friction force calculation unit 608c has not calculated the current static friction force F0' using equation (1) in the current control cycle. comp Set to 0 (zero). Also, the static friction compensation amount calculation unit 608d calculates the value at time t when the actual drum torque values ​​731-733 first reach the drum torque command values ​​741-743 after the plate tension setting value has been changed (from F1 to F2). d So, static friction compensation amount T comp Let this be 0 (zero). The static friction compensation amount calculation unit 608d calculates the static friction compensation amount T as described above. comp This is output to the static friction compensation amount correction unit 609.

[0110] The static friction compensation amount correction unit 609 uses the reference torque T calculated by the torque conversion unit 607. R The static friction compensation amount T calculated by the static friction compensation amount calculation unit 608d comp The correction is made based on the reference torque T calculated by the torque conversion unit 607. In this embodiment, the static friction compensation amount correction unit 609 corrects the reference torque T calculated by the torque conversion unit 607. R And, static friction compensation amount T comp Add and . This addition occurs at time t c It may be performed all at once. However, from the viewpoint of achieving stable control, in this embodiment, the static friction compensation amount correction unit 609 is performed at time t in Figures 7A to 7C. c ~t d As shown in the drum torque command values ​​741-743, the reference torque T calculated by the torque conversion unit 607 R Adding a constant torque to this is called adding a constant torque to the static friction compensation amount T calculated by the static friction compensation amount calculation unit 608d. comp This process is repeated in each control cycle until the desired result is reached.

[0111] In this case, time t c In this case, the reference torque T calculated by the torque conversion unit 607 R Compensation (torque addition) for this starts, at time t dIn this case, the reference torque T calculated by the torque conversion unit 607 R The static friction compensation amount T calculated by the static friction compensation amount calculation unit 608d comp The added value is calculated as the drum torque command value 741-743. This added value is the torque that compensates for the current static friction force F0' in order to apply an external force exceeding the maximum static friction force F0 to the looper trolley 206, with respect to a torque that cancels out the plate tension deviation. In the following explanation, the torque in which the current static friction force F0' has been compensated in this way is referred to as the static friction-compensated torque T, as needed. RF This is called the torque T after compensating for static friction. RF This is an example of the manipulated amount after compensating for static friction. As will be described later, in this embodiment, we will illustrate a case where, in addition to the static friction force F0', mechanical losses in the looper trolley 206 and the inertia generated in the looper trolley 206 are also compensated. Therefore, the manipulated amount after these compensations are made is also an example of the manipulated amount after compensating for static friction.

[0112] As mentioned above, in this embodiment, the time t when the plate tension setting value 711 is changed from F1 to F2 a Therefore, the time t when the board tension command value 721 becomes the changed board tension setting value 711 (=F2) b During this period, the static friction force calculation unit 608c calculates the current static friction force F0', and the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T comp The following is calculated. Therefore, the static friction compensation amount correction unit 609 calculates at time t a From time t b During the period up to, the torque T after compensating for static friction RF Calculate.

[0113] More specifically in this embodiment, such time t a From time t b During the period up to the time t, the plate tension command value 721 becomes the plate tension reference value Fs. c The static friction force calculation unit 608c calculates the current static friction force F0', and the static friction compensation amount T is calculated by the static friction compensation amount calculation unit 608d. compThe following is calculated. Therefore, the static friction compensation amount correction unit 609 determines the time t when the plate tension command value 721 becomes the plate tension reference value Fs. c Then, the torque T after compensating for static friction RF Calculate.

[0114] Furthermore, in this embodiment, after the plate tension setting value is changed (from F1 to F2), the time t when the actual drum torque value 731-733 becomes the drum torque command value 741-743 d Then, the static friction compensation amount T is calculated by the static friction compensation amount calculation unit 608d. comp This is changed to 0 (zero). Therefore, the static friction compensation amount correction unit 609 is set to the time t after the plate tension setting value is changed (from F1 to F2) when the actual drum torque value 731~733 becomes the drum torque command value 741~743. d Then, the reference torque T calculated by the torque conversion unit 607 R Static friction compensation amount T to be added comp Set it to 0 (zero).

[0115] The mechanical loss compensation unit 610 calculates the amount of torque compensation to compensate for the mechanical losses during movement of the looper trolley 206. For example, the mechanical loss compensation unit 610 has a relationship formula between the movement speed of the looper trolley 206 and the amount of torque compensation stored in advance, and calculates the amount of torque compensation using this relationship formula and the actual trolley speed value. Alternatively, a lookup table may be used instead of the relationship formula.

[0116] The mechanical loss compensation amount correction unit 611 corrects the static friction-compensated torque T calculated by the static friction compensation amount correction unit 609. RF This is corrected based on the torque compensation amount calculated by the mechanical loss compensation unit 610. In this embodiment, the mechanical loss compensation amount correction unit 611 corrects the static friction-compensated torque T calculated by the static friction compensation amount correction unit 609. RFThis is added to the torque compensation amount calculated by the mechanical loss compensation unit 610. This added value is the torque that compensates for the current static friction force F0' and the mechanical loss during movement of the looper trolley 206, with respect to the torque that cancels out the plate tension deviation. In the following explanation, the torque in which the mechanical loss of the looper trolley 206 has been compensated in this way is referred to as the torque T after compensation for static friction and mechanical loss, as needed. RFM It is called that.

[0117] The inertia compensation unit 612 calculates the amount of torque compensation to compensate for the inertia generated in the looper trolley 206. For example, the inertia compensation unit 612 calculates the acceleration of the looper trolley 206 by taking the first derivative of the actual trolley speed value, and calculates the amount of torque compensation by multiplying the acceleration of the looper trolley 206 by a constant.

[0118] The inertia compensation amount correction unit 613 corrects the torque T after compensating for static friction and mechanical losses calculated by the mechanical loss compensation amount correction unit 611. RFM This is corrected based on the torque compensation amount calculated by the inertia compensation unit 612. In this embodiment, the inertia compensation amount correction unit 613 corrects the torque T after compensating for static friction and mechanical losses calculated by the mechanical loss compensation amount correction unit 611. RFM This is added to the torque compensation amount calculated by the inertia compensation unit 612. This added value is the torque T after compensating for static friction and mechanical losses. RFM In contrast, this is the torque after compensating for the inertia generated in the looper trolley 206. That is, this sum is the torque after compensating for the current static friction force F0', the mechanical loss during movement of the looper trolley 206, and the inertia generated in the looper trolley 206, with respect to a torque that cancels out the plate tension deviation. In the following explanation, the torque after compensating for static friction, mechanical loss, and inertia, in this way, is referred to as the torque T after compensating for static friction, mechanical loss, and inertia, as needed. RFMI It is called that.

[0119] The command unit 614 is equipped with an inverter circuit and calculates static friction, mechanical loss, and inertia-compensated torque T by the inertia compensation amount correction unit 613. RFMIThe command unit 614 sets the drum torque command value for the current control cycle and generates an excitation current corresponding to the drum torque command value, which is then output to the looper motor 207. The command unit 614 also outputs the drum torque command value for the current control cycle to the static friction compensation amount calculation unit 608d. In this embodiment, the command unit 614 generates and outputs an excitation current as an example of a drive signal for driving the looper trolley 206. However, the drive signal is not limited to an excitation current; for example, it may be an excitation voltage, or a signal used when generating the excitation current in the inverter. Furthermore, the drive signal for driving the looper trolley 206 may be generated by a part other than the command unit 614.

[0120] <Flowchart> Next, an example of a loop control method performed using the looper control device 110 (static friction compensation unit 608 and static friction compensation amount correction unit 609) will be explained with reference to the flowchart in Figure 8. Here, the process of compensating the current static friction force F0' in order to apply an external force exceeding the maximum static friction force F0 to the looper trolley 206 will be explained. It is assumed that one iteration of steps S801 to S818 in Figure 8 is performed within the same control cycle. Also, in Figure 8, for the sake of simplicity, the compensation amounts by the mechanical loss compensation amount correction unit 611 and the inertia compensation amount correction unit 613 are assumed to be 0 (zero).

[0121] First, in step S801, the tension setting change determination unit 608a determines whether the plate tension setting value has been changed (from F1 to F2) based on the plate tension setting value acquired by the operation setting value acquisition unit 602. In the example shown in Figures 7A to 7C, time t a Step S801 determines whether or not this has occurred. If the result of this determination is that the board tension setting value has not been changed (the result in NO in step S801), the process in step S817, which will be described later, is performed.

[0122] On the other hand, if the plate tension setting value is changed (if YES is given in step S801), in step S802, the static friction force calculation unit 608c calculates the plate tension reference value Fs using equation (3). In the example shown in Figures 7A to 7C, time t a Since the actual bogie speed values ​​of 761-763 are 0 (zero), the process in step S802 is performed.

[0123] Next, in step S803, the trolley speed determination unit 608b determines whether the trolley speed value obtained by the operation performance acquisition unit 601 is 0 (zero). If the result of this determination is that the trolley speed value is not 0 (the result in NO in step S803), the process in step S817, which will be described later, is performed.

[0124] On the other hand, if the actual bogie speed value is 0 (zero) (if the answer is YES in step S803), in step S804, the static friction force calculation unit 608c reads the plate tension command value 721 for the current control cycle.

[0125] Next, in step S805, the static friction force calculation unit 608c determines whether the plate tension command value 721 in the current control cycle has reached the plate tension reference value Fs. In the example shown in Figures 7A to 7C, time t c Whether or not this has been achieved is determined in step S805. If, as a result of this determination, the plate tension command value 721 in the current control cycle is not equal to the plate tension reference value Fs (the result in NO in step S805), the process described in step S803 is repeated.

[0126] Then, when the plate tension command value 721 in the current control cycle becomes the plate tension reference value Fs (if YES in step S805), in step S806, the static friction force calculation unit 608c calculates the current static friction force F0' using equation (1).

[0127] Next, in step S807, the static friction compensation amount calculation unit 608d determines whether the changed plate tension setting value F2 is greater than the original plate tension setting value F1 (F2 > F1).

[0128] As a result of this determination, when the changed sheet tension set value F2 exceeds the sheet tension set value F1 before the change (F2 > F1) (YES in step S807), in step S808, the static friction compensation amount calculation unit 608d calculates the static friction force correction amount F comp using equation (5a). The static friction force correction amount F comp is the frictional force required to compensate the current static friction force F0' so that the static friction force F0' between the looper carriage 206 and the rail 208 becomes the maximum static friction force F0. In the example shown in FIGS. 7A to 7C, since the changed sheet tension set value F2 exceeds the sheet tension set value F1 before the change (F2 > F1), the process of step S808 is performed. When the process of step S808 ends, the process of step S810 described later is performed.

[0129] On the other hand, when the changed sheet tension set value F2 does not exceed the sheet tension set value F1 before the change (F2 < F1) (NO in step S807), in step S809, the static friction compensation amount calculation unit 608d calculates the static friction force correction amount F comp using equation (5b). When the process of step S809 ends, the process of the following step S810 is performed.

[0130] In step S810, the static friction compensation amount calculation unit 608d converts the static friction force correction amount F comp into torque to calculate the torque correction amount T' comp using equation (7). Next, in step S811, the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T comp (= T' comp × β) using equation (8).

[0131] Next, in step S812, the static friction compensation amount correction unit 609 calculates the value obtained by adding the reference torque T R calculated by the torque conversion unit 607 and the static friction compensation amount T comp calculated by the static friction compensation amount calculation unit 608d as the torque after static friction compensation T RF In the example shown in FIGS. 7A to 7C, the process of step S812 is performed at time tc From time t d This corresponds to the fact that the actual drum torque value of 731-733 increased at a constant rate during the period up to that point.

[0132] Next, in step S813, the static friction compensation amount calculation unit 608d reads the drum torque command values ​​741 to 743 for the current control cycle generated by the command unit 614. Next, in step S814, the static friction compensation amount calculation unit 608d reads the drum torque actual values ​​731 to 733 for the current control cycle, which have been acquired by the operation performance acquisition unit 601.

[0133] Next, in step S815, the static friction compensation amount calculation unit 608d determines whether the actual drum torque values ​​731-733 in the current control cycle have become the drum torque command values ​​741-743 in the current control cycle. In the example shown in Figures 7A-7C, time t d Whether or not this has happened is determined in step S815.

[0134] If, as a result of this determination, the actual drum torque values ​​731-733 for the current control cycle do not match the drum torque command values ​​741-743 for the current control cycle (if NO in step S815), the process described in step S814 is repeated. Then, if the actual drum torque values ​​731-733 for the current control cycle match the drum torque command values ​​741-743 for the current control cycle (if YES in step S815), in step S816, the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T comp Determine whether it is 0 (zero).

[0135] Based on this determination, the static friction compensation amount T compIf the value is not 0 (i.e., NO in step S816), the process in step S817 is performed. As mentioned above, the process in step S817 is also performed if it is determined in step S801 that the plate tension setting value has not been changed (i.e., NO in step S801), and if it is determined in step S803 that the actual bogie speed value is not 0 (i.e., NO in step S803).

[0136] In step S817, the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T comp Set to 0 (zero). In this case, the static friction compensation amount correction unit 609 uses the reference torque T calculated by the torque conversion unit 607. R This is output directly to the mechanical loss compensation amount correction unit 611. Then, the processing in step S813 described above is performed, and in step S816, the static friction compensation amount T comp The processes in steps S817 and S813-S816 are repeated until it is determined that the value is 0 (zero) (until it is determined to be YES in step S816).

[0137] Then, in step S816, the static friction compensation amount T comp If it is determined that the value is 0 (zero) (if YES in step S816), then in step S818, the looper control device 110 determines whether the operation has ended due to the completion of the transport of steel strip S in the continuous galvanizing line. The method of determination in step S816 is not particularly limited. For example, the looper control device 110 may determine that the operation has ended when a sensor (not shown) detects that there are no steel strips S in the continuous galvanizing line. Alternatively, the looper control device 110 may determine that the operation has ended when an operator performs an input operation to instruct the looper control device 110 that the operation has ended.

[0138] As a result of this determination, if the operation ends (YES in step S817), the processing according to the flowchart in FIG. 8 ends. On the other hand, if the operation does not end (NO in step S818), the processing in step S801 is executed again. Note that the processing in steps S801 to S818 in FIG. 8 is executed in the same control cycle, and if it is determined as NO in step S818, the processing after step S801 in the next control cycle will be executed.

[0139] <Summary> As described above, in this embodiment, when the strip tension set value is changed while the looper carriage 206 is stationary, the looper control device 110 calculates the static friction compensation operation amount for applying an external force exceeding the maximum static friction force F0 to the looper carriage 206 as the operation amount for controlling the tension of the steel strip S. Therefore, when the strip tension command value is changed while the looper carriage 206 in the loop storage device including the looper carriage 206 is stationary, it is possible to suppress the deviation between the strip tension actual value and the strip tension command value.

[0140] Also, in this embodiment, when the strip tension set value is changed while the looper carriage 206 is stationary, the looper control device 110 uses the static friction compensation amount T, which is the compensation amount for compensating the static friction force F0 between the looper carriage 206 and the rail 208 and is the compensation amount that makes the external force applied to the looper carriage 206 larger than before the change of the strip tension set value. comp is calculated. Therefore, when the strip tension set value is changed while the looper carriage 206 is stationary, by compensating the static friction force F0 between the looper carriage 206 and the rail 208, an external force exceeding the maximum static friction force F0 can be applied to the looper carriage 206. [[ID=!3]] can be achieved.

[0141] In addition, in the present embodiment, the looper control device 110 calculates the static friction force F0' generated between the looper carriage 206 and the rail 208 against the external force applied to the looper carriage 206, and based on the maximum static friction force F0 between the looper carriage 206 and the rail 208 and the calculated static friction force F0', calculates the static friction compensation amount T comp Thereby, the external force required to move the looper carriage 206 can be quantitatively calculated.

[0142] In addition, in the present embodiment, the looper control device 110 calculates the static friction compensation amount T so that the static friction force F0 between the looper carriage 206 and the rail 208 is compensated by a friction force having an absolute value larger than the absolute value of the difference between the maximum static friction force F0 between the looper carriage 206 and the rail 208 and the static friction force F0' calculated as described above. comp Thereby, the external force required to reliably move the looper carriage 206 can be quantitatively calculated. [[ID=十]]

[0143] In addition, in the present embodiment, the looper control device 110 calculates the correction amount for the torque of the looper motor 207 as the static friction compensation amount T comp Thereby, the torque required for the looper motor 207 to move the looper carriage 206 can be calculated. Thus, the looper control device 110 can be applied to a form of controlling the tension of the steel strip S using the looper motor 207. <00,00914> In addition, in the present embodiment, the looper control device 110 calculates the sheet tension command value 721 as the target value of the tension of the steel strip S at each time (each control cycle) based on the sheet tension set value 711, and from the time t when the sheet tension set value 711 is changed from F1 to F2 a to the time t when the sheet tension command value 72 has become the changed sheet tension set value 711 (F2), during this period, corrects the reference torque T b R comp < based on the static friction compensation amount T comp That is, based on the static friction compensation amount T comp(The compensated control amount is calculated). Therefore, it is possible to prevent the timing of compensating for the static friction force F0 between the looper trolley 206 and the rail 208 from becoming too late.

[0145] Furthermore, in this embodiment, the looper control device 110 determines the time t when the plate tension command value 721 reaches a plate tension reference value Fs, which is a value that divides the plate tension setting value 711(F1) before the change and the plate tension setting value 711(F2) after the change by a predetermined internal division ratio. c , or the time t when the board tension setting value 711 was changed a And the time t when the board tension command value 721 becomes the changed board tension setting value 711 (F2) b The time t divides the given time by a predetermined internal division ratio. c So, the reference torque T R Static friction compensation amount T comp Correction based on (i.e., static friction compensation amount T) comp The calculation of the compensated control amount is initiated. Therefore, the timing of compensating for the static friction force F0 between the looper trolley 206 and the rail 208 can be further suppressed.

[0146] Furthermore, in this embodiment, when the looper control device 110 receives information indicating that the looper trolley 206 has moved, it sets the static friction compensation amount T comp Set it to 0 (zero) (i.e., static friction compensation amount T) comp (The calculation of the compensated maneuver amount is not performed.) Therefore, the looper trolley 206 is in the synchronous position L s It is possible to suppress movement to a position far away from the target. In this embodiment, after the plate tension setting value is changed (from F1 to F2), the time t when the actual drum torque value 731-733 becomes the drum torque command value 741-743 d Static friction compensation amount T compAn example was given of setting it to 0 (zero). In this case, the information indicating that the looper trolley 206 has moved is the information that the actual drum torque value 731-733 became the drum torque command value 741-743 after the plate tension setting value was changed (from F1 to F2). However, the information indicating that the looper trolley 206 has moved is not limited to this information. For example, the information indicating that the looper trolley 206 has moved may be information indicating that the rotational speed of the looper motor 207 has exceeded 0 (zero), or information indicating that the amount of change per unit time of the tension (actual plate tension value) applied to the steel strip S detected by the tension detector 209 has exceeded a threshold.

[0147] Here, the method for calculating the manipulated amount after static friction compensation is not limited to the method described in this embodiment. For example, the manipulated amount calculation unit 600 may use a machine learning model (e.g., a neural network) that includes all or part of the actual values, command values, and set values ​​of the manufacturing line (e.g., plate tension command value, plate tension set value, actual plate tension value, trolley speed actual value, plate tension actual value, and drum torque actual value) as explanatory variables, and the manipulated amount after static friction compensation (drum torque command value) as the objective variable, to calculate the manipulated amount after static friction compensation when the plate tension set value is changed while the looper trolley 206 is stationary. Alternatively, for example, the functions of the static friction force calculation unit 608c and the static friction compensation amount calculation unit 608d may be implemented using a machine learning model.

[0148] As mentioned above, in this embodiment, the functions and processing of the looper control device 110 were illustrated using the inlet looper 103 as an example of a loop storage device. However, the loop storage device controlled by the looper control device 110 is not limited to the inlet looper 103, but may be, for example, the outlet looper 107. Furthermore, in this embodiment, an example of a moving path, the rail 208, is shown as being laid along the installation surface (floor) of the continuous hot-dip galvanizing line. However, this is not necessarily required. For example, the rail may be installed perpendicular to the installation surface (floor) of the continuous hot-dip galvanizing line (vertical direction) or in the direction of gravity (z-axis direction), and the looper trolley may move perpendicular to the installation surface (floor) of the continuous hot-dip galvanizing line (vertical direction) or in the direction of gravity (z-axis direction). For example, the entry-side looper 103 and the exit-side looper 107 may be vertical loopers. A vertical looper is a looper configured such that the angle between the direction of movement of the looper trolley 206 and the direction of gravity acting on the steel strip S is approximately 0° when the steel strip S is transported. Furthermore, although this embodiment illustrates a case where the continuous processing line is a continuous hot-dip galvanizing line, the continuous processing line is not limited to a continuous hot-dip galvanizing line; any line on which a loop storage device is installed may be used.

[0149] (Second Embodiment) Next, a second embodiment of the present invention will be described. In the first embodiment, the current static friction force F0' calculated by equation (1) is used, and the static friction compensation amount T calculated by the static friction compensation unit 608 is used. comp The timing at which compensation begins (time t) c In this process, compensation for static friction force F0' is performed only once (i.e., only once with static friction compensation amount T). comp (Setting). Therefore, due to the effects of various losses such as mechanical losses, static friction compensation amount T comp If an error occurs in the calculation, the static friction compensation amount T compIt is possible that the absolute value of may be smaller than the amount of compensation required to compensate for the maximum static friction force F0. To prevent this, the magnitude of the coefficient β may be increased so that an external force exceeding the maximum static friction force F0 is applied to the looper trolley 206 in a single compensation of the static friction force F0'. However, if the magnitude of the coefficient β is increased too much, the torque command value may become unnecessarily large, potentially leading to overcompensation. Therefore, in this embodiment, after the compensation of the static friction force F0' has started, if the actual drum torque value reaches the drum torque command value but the actual trolley speed value is 0 (zero), the compensation of the static friction force F0' is repeated until the actual trolley speed value is no longer 0 (zero). Thus, this embodiment and the first embodiment differ mainly in their configuration and processing due to the different method of compensating for the static friction force F0'. Accordingly, in the description of this embodiment, parts that are the same as those in the first embodiment will be denoted by the same reference numerals as those in Figures 1 to 8, and detailed explanations will be omitted.

[0150] Figure 9 is a conceptual diagram illustrating an example of the relationship between plate tension, drum torque, and trolley speed and time. Figure 9 shows the relationship when the internal division ratio parameter α is 1 (α=1). In this embodiment, the relationship shown in Figure 7A becomes the relationship shown in Figure 9.

[0151] time t a This is the time t shown in Figure 7A. a This is the time corresponding to time t. a This is the time when the board tension setting value of 911 is changed from F1 to F2. time t b This is the time t shown in Figure 7A. b This is the time corresponding to time t. b This is the time when the board tension command value 921 becomes the board tension setting value 911 after the board tension setting value 911 is changed from F1 to F2.

[0152] time t c1 This is the time t shown in Figure 7A. c This is the time corresponding to time t. c1This is the time at which the current static friction force F0' is calculated using equation (1), and the current static friction force F0' calculated using equation (1) is used to calculate the static friction compensation amount T calculated by the static friction compensation unit 608 (static friction compensation amount calculation unit 608d). comp_1 This is the time when compensation begins. In the first embodiment, time t c In the case of static friction compensation amount T comp This is calculated. On the other hand, in this embodiment, time c The corresponding time c1 In the case of static friction compensation amount T comp_1 This is calculated.

[0153] time t c2 This is the static friction compensation amount T. comp_1 This is the time when the actual drum torque value 931 becomes equal to the drum torque command value 941 after compensation for static friction force F0' by the system begins. In Figure 9, time t c2 In this example, the actual bogie speed value of 961 remains 0 (zero). In the first embodiment, the static friction compensation amount T comp_1 After compensation for static friction force F0' is initiated, the time t becomes equal to the actual drum torque value 931 and the commanded drum torque value 941. c2 In this case, the actual bogie speed value of 961 is not kept at 0 (i.e., at time t c2 (In this case, the actual bogie speed value of 961 is not 0 (zero).) In contrast, in Figure 9, at time t c2 In this embodiment, the actual bogie speed value 961 remains 0 (zero). In this embodiment, in such a case, the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T comp_2 The static friction compensation amount T is recalculated. At this time, the static friction compensation amount T is calculated by the static friction compensation amount calculation unit 608d. comp_2 The absolute value of is the static friction compensation amount T comp_1 The static friction compensation amount T should be greater than the absolute value of comp_2 It is described as follows. And at time t c2 In the case of static friction compensation amount T comp_2 Compensation for static friction force F0' begins.

[0154] time t c3 This is the static friction compensation amount T.comp_2 This is the time when the actual drum torque value of 931 equals the commanded drum torque value of 941 after compensation for static friction force F0' by the start of the process. In Figure 9, time t c3 In this example, the bogie speed actual value 961 remains 0 (zero). In this embodiment, in such a case, the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T comp_3 The static friction compensation amount T is recalculated. At this time, the static friction compensation amount T is calculated by the static friction compensation amount calculation unit 608d. comp_3 The absolute value of is the static friction compensation amount T comp_2 The static friction compensation amount T should be greater than the absolute value of comp_3 It is described as follows. And at time t c3 In the case of static friction compensation amount T comp_3 Compensation for static friction force F0' begins.

[0155] time t d This is the time t shown in Figure 7A. d This corresponds to the time shown in Figure 7A. d This is the static friction compensation amount T. comp This is the time when, after compensation for static friction force F0' begins, the actual drum torque value 731 first reaches the drum torque command value 741, which is the target value for each time (each control cycle) of the drum torque. On the other hand, time t shown in Figure 9 d (Static friction compensation amount T) comp_1 (Not) Static friction compensation amount T comp_3 This is the time when, after compensation for static friction force F0' begins, the actual drum torque value 931 first reaches the drum torque command value 941, which is the target value for each time (each control cycle) of the drum torque. In Figure 9, time t d In this case, the actual bogie speed value of 961 is no longer 0 (zero), and the looper bogie 206 starts to move. Therefore, the time t shown in Figure 9 is an example. d In this process, the current static friction force F0' calculated by equation (1) is used in the static friction compensation amount T calculated by the static friction compensation unit 608. comp_1 ~T comp_3 Compensation will cease as a result.

[0156] As described above, in this embodiment, after the static friction compensation amount calculation unit 608d starts compensating for the static friction force F0', if the actual drum torque value 931 becomes the drum torque command value 941, but the actual bogie speed value 961 is 0 (zero), the static friction compensation amount T comp_n The calculation is repeated. Then, the static friction compensation amount T comp_n The static friction force F0' is repeatedly compensated by T. Here, n represents the number of times the static friction force F0' is compensated. Static friction compensation amount T comp_n This is the amount of static friction compensation calculated during the nth compensation of the static friction force F0'. As mentioned above, the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T comp_n The absolute value of the previous static friction compensation amount T comp_n-1 The static friction compensation amount T is set to be greater than the absolute value of comp_n Calculate.

[0157] Static friction compensation amount T comp_n The method for calculating the static friction compensation amount T is not particularly limited. For example, when the static friction force F0' is compensated for the first time (n=1), the static friction compensation amount T is calculated using equations (5a) to (8) as described in the first embodiment. comp_1 You may calculate this. In this case, T on the left side of equation (8) comp is, T comp_1 This is how it works. Then, when the static friction compensation amount calculation unit 608d compensates for the static friction force F0' for the second time or later (n≧2), it uses the previous static friction compensation amount T comp_n-1 A predetermined constant torque correction amount T' comp_cst The static friction compensation amount T is calculated by adding (N·m). comp_n It can also be calculated as follows: Torque correction amount T' comp_cst The value of may be a constant value (the same value regardless of the number of times the static friction force F0' is compensated n), but it may also be a different value depending on the number of times the static friction force F0' is compensated n. For example, the torque correction amount T' increases as the number of times the static friction force F0' is compensated n increases. comp_cst It is also acceptable to make the absolute value of smaller. Conversely, the torque correction amount T' increases as the number of compensations n for the static friction force F0' increases.comp_cst The absolute value of can also be made larger. In addition, the torque correction amount T' comp_cst You may also set it randomly within a predetermined range.

[0158] The static friction compensation amount T is calculated using equations (5a) to (8). comp_1 When calculating the static friction compensation amount T, comp Due to the effects of calculation errors, etc., the static friction compensation amount T comp_1 Even if the absolute value of is smaller than the amount of compensation required to compensate for the maximum static friction force F0, the static friction compensation amount T comp_1 It is assumed that this value is relatively close to the amount of compensation required to compensate for the maximum static friction force F0. Therefore, when compensating for the static friction force F0' for the first time (n=1), the amount of static friction compensation T is calculated using equations (5a) to (8). comp_1 By calculating this, it becomes possible to reduce the number of times n is compensated for the static friction force F0'. Furthermore, when compensating for the static friction force F0' from the second time onward (n≧2), the static friction compensation amount T comp_n-1 A constant torque correction amount T' comp_cst The static friction compensation amount T is calculated by repeatedly adding the sums. comp_n-1 If the deficit is compensated for, the compensation amount (T') in the compensation for the static friction force F0' from the second time onward (n≧2) will be comp_cst The magnitude of ) is the static friction compensation amount T comp_1 It can be determined based on the value assumed to be the deficit. Therefore, a constant torque correction amount T' comp_cst The value to be adopted can be determined relatively easily.

[0159] However, static friction compensation amount T comp_n The method of calculation is not limited to the above method. For example, the static friction compensation amount calculation unit 608d calculates a constant torque correction amount T' regardless of the number of times n the static friction force F0' is compensated. comp_cst The previous static friction compensation amount T comp_n-1 The value added to this is the static friction compensation amount T. comp_n It may also be calculated as follows. Furthermore, as mentioned above, the torque correction amount T' comp_cst The value of may vary depending on the number of times n is compensated for by static friction force F0'.

[0160] In addition, an example of the relationship between the sheet tension, the drum torque, and the carriage speed and time when the internal ratio parameter α is a value other than 1 is represented by making changes as shown in FIGS. 7B and 7C with respect to FIG. 9. Therefore, here, a detailed description of an example of the relationship between the sheet tension, the drum torque, and the carriage speed and time when the internal ratio parameter α is a value other than 1 is omitted.

[0161] Next, an example of the loop control method performed using the looper control device 110 (the static friction compensation unit 608 and the static friction compensation amount correction unit 609) will be described while referring to the flowcharts of FIGS. 10-1 to 10-2. In the present embodiment, processing according to the flowcharts of FIGS. 10-1 to 10-2 is performed instead of the flowchart of FIG. 8. Similar to FIG. 8, in FIGS. 10-1 to 10-2 as well, the process of compensating the current static friction force F0' in order to apply an external force exceeding the maximum static friction force F0 to the looper carriage 206 will be described. Also, it is assumed that one repetition process of steps S1001 to S1027 in FIGS. 10-1 to 10-2 is executed in the same control cycle. Further, in FIGS. 10-1 to 10-2, for the sake of simplicity of explanation, the compensation amounts by the mechanical loss compensation amount correction unit 611 and the inertia compensation amount correction unit 613 are assumed to be 0 (zero).

[0162] Steps S1001 to S1012 in FIG. 10-1 are the same as steps S801 to S812 in FIG. 8. When it is determined in step S1001 that the sheet tension set value has not been changed (NO in step S1001), the process of step S1024 in FIG. 10-2 described later is performed. Also, in the description of step S805, in the example shown in FIG. 9 (not at time t c but) whether it has reached time t c1 is determined in step S805. Also, the symbol of the static friction force correction amount in the descriptions of steps S808 and S809 is (F comp not) F comp_1 becomes. Also, in the description of step S812, from time t c to time t dThe fact that the actual drum torque values ​​of 731-733 increased at a constant slope during the period up to time t is shown in Figure 9. c1 From time t c2 This corresponds to the fact that the actual drum torque value of 931 increased at a constant rate during the period up to that point. Furthermore, the processing in steps S1002 to S1012 in Figure 10-1 corresponds to the processing for the first (n=1) compensation of the static friction force F0'.

[0163] When the processing in step S1012 is completed, the processing in step S1013 is performed. In step S1013, the static friction compensation amount calculation unit 608d sets the number of times n for compensation of the static friction force F0' to "2". Next, in step S1014 of Figure 10-2, the static friction compensation amount calculation unit 608d reads the drum torque command value 941 for the current control cycle generated by the command unit 614.

[0164] Next, in step S1015, the trolley speed determination unit 608b determines whether the trolley speed value obtained by the operation performance acquisition unit 601 is 0 (zero). If the result of this determination is that the trolley speed value is not 0 (the result is NO in step S1015), the process in step S1024, which will be described later, is performed.

[0165] On the other hand, if the actual bogie speed value is 0 (zero) (if YES in step S1015), in step S1016, the static friction compensation amount calculation unit 608d reads the actual drum torque value 931 for the current control cycle, which has been acquired by the operation performance acquisition unit 601.

[0166] Next, in step S1017, the static friction compensation amount calculation unit 608d determines whether the actual drum torque value 931 in the current control cycle has become the drum torque command value 941 in the current control cycle. In the example shown in Figure 9, at time t cn Whether or not this has happened is determined in step S1017.

[0167] As a result of this determination, if the actual drum torque value 931 in the current control cycle is not equal to the drum torque command value 941 in the current control cycle (NO in step S1017), the process of step S1015 described above is performed again. And when the actual drum torque value 931 in the current control cycle becomes equal to the drum torque command value 941 in the current control cycle (YES in step S1017), in step S1018, the static friction compensation amount calculation unit 608d reads a certain torque correction amount T' comp_cst from it.

[0168] Next, in step S1019, the static friction compensation amount calculation unit 608d determines whether the changed sheet tension set value F2 is greater than the previous sheet tension set value F1 (F2 > F1). As a result of this determination, if the changed sheet tension set value F2 is greater than the previous sheet tension set value F1 (F2 > F1) (YES in step S1019), in step S1020, the static friction compensation amount calculation unit 608d calculates the value obtained by adding a certain torque correction amount T' comp_n-1 to the previous static friction compensation amount T comp_cst as the static friction compensation amount T comp_n (T comp_n = T comp_n-1 + T' comp_cst ). When the process of step S1020 ends, the process of step S1012 described later is performed.

[0169] On the other hand, if the changed sheet tension set value F2 is not greater than the previous sheet tension set value F1 (F2 < F1) (NO in step S1019), in step S1021, the static friction compensation amount calculation unit 608d calculates the value obtained by subtracting a certain torque correction amount T' comp_n-1 from the previous static friction compensation amount T comp_cst as the static friction compensation amount T comp_n (T comp_n = T comp_n-1 - T' comp_cst ). When the process of step S1021 ends, the process of the following step S1022 is performed.

[0170] In step S1022, the static friction compensation amount correction unit 609 uses the reference torque T calculated by the torque conversion unit 607. R And the static friction compensation amount T calculated by the static friction compensation amount calculation unit 608d comp_n The sum of these values ​​is the torque T after compensating for static friction. RF It is calculated as follows. In the example shown in Figure 9, the process in step S1022 is performed at time t c2 From time t c3 , time t c3 From time t d This corresponds to the fact that the actual drum torque value of 931 increased at a constant rate during the period up to that point.

[0171] Next, in step S1023, the static friction compensation amount calculation unit 608d updates the number of times the static friction force F0' is compensated n by adding "1". When the processing in step S1023 is completed, the processing in step S1014 in Figure 10-2 is performed again. The processes from step S1013 in Figure 10-1 to step S1023 in Figure 10-2 correspond to the process for compensating for the nth (n≧2) static friction force F0'.

[0172] As mentioned above, if it is determined in step S1015 that the actual bogie speed value is not 0 (if NO in step S1015), and if it is determined in step S1001 that the plate tension setting value has not been changed (if NO in step S1001), the process in step S1024 is performed. In step S1024, the static friction compensation amount calculation unit 608d calculates the static friction compensation amount T comp_1 ~T comp_n Set to 0 (zero). In this case, the static friction compensation amount correction unit 609 uses the reference torque T calculated by the torque conversion unit 607. R This is output directly to the mechanical loss compensation amount correction unit 611.

[0173] Next, in step S1025, and in step S1026, the static friction compensation amount calculation unit 608d reads the actual drum torque value 931 for the current control cycle, which has been acquired by the operational performance acquisition unit 601.

[0174] Next, in step S1026, the static friction compensation amount calculation unit 608d determines whether the actual drum torque value 931 in the current control cycle has become the drum torque command value 941 in the current control cycle. In the example shown in Figure 9, at time t d Whether or not this has happened is determined in step S1026.

[0175] If, as a result of this determination, the actual drum torque value 931 for the current control cycle does not match the drum torque command value 941 for the current control cycle (the result is NO in step S1026), the process in step S1025 described above is repeated. Then, when the actual drum torque value 931 for the current control cycle matches the drum torque command value 941 for the current control cycle (the result is YES in step S1026), in step S1027, the looper control device 110 determines whether the operation has ended due to the completion of the transport of the steel strip S in the continuous galvanizing line. The determination method in step S1027 is the same as the determination method in step S818 in Figure 8.

[0176] If the operation is terminated as a result of this determination (YES in step S1027), the process according to the flowcharts in Figures 10-1 and 10-2 is terminated. On the other hand, if the operation is not terminated (NO in step S1027), the process in step S1001 is executed again. Note that the processes in steps S1001 to S1027 in Figures 10-1 to 10-2 are executed in the same control cycle, and if NO is determined in step S1027, the processes from step S1001 onwards in the next control cycle will be executed.

[0177] For example, when compensating for the static friction force F0' for the first time (n=1), the static friction compensation amount T is calculated using equations (5a) to (8). comp_1 Without calculating the number of times the static friction force F0' is compensated, a constant torque correction amount T' is used. comp_cst The previous static friction compensation amount T comp_n-1 The value added to this is the static friction compensation amount T. comp_nWhen calculated in this way, the flowcharts in Figures 10-1 to 10-2 are modified as follows, for example. Note that in this case, the static friction compensation amount T calculated during the nth compensation is comp_n In each case, the compensation amount becomes larger than before the plate tension setting value was changed, and the more times compensation is performed (the larger n is), the greater the external force applied to the looper trolley 206 becomes. Thus, the static friction compensation amount T calculated at the nth compensation is comp_n This is calculated to apply an external force exceeding the maximum static friction force F0 to the looper trolley 206.

[0178] First, the process in step S1006 in Figure 10-1 is as follows. That is, in step S1006, the static friction compensation amount calculation unit 608d sets the number of compensations n for the static friction force F0' to "1". Then, after the process of step S1006 has been modified in this way, the processes of steps S1007 to S1013 are not performed (as if the processes of steps S1007 to S1013 do not exist), and the processes of steps S1018 to S1023 in Figure 10-2 are performed. Note that in steps S1020 and S1021, the T when n=1 comp_n-1 (=T comp_0 ) becomes 0 (zero).

[0179] As described above, in this embodiment, after the looper control device 110 starts controlling the tension of the steel strip S so that the actual drum torque value 931 becomes the drum torque command value 941, if the actual bogie speed value 961 is 0 (zero) and the looper bogie 206 is stationary, the already calculated static friction compensation amount T comp_1 ~T comp_n-1 Static friction compensation amount T, which has a larger absolute value than comp_n The static friction compensation amount T is calculated. comp_n Due to the effects of calculation errors, etc., static friction compensation amount T comp_nThis method prevents the absolute value of from remaining smaller than the amount of compensation required to compensate for the maximum static friction force F0 without causing overcompensation. Therefore, it is possible to suppress the decrease in control performance due to overcompensation (for example, the actual plate tension value hunting relative to the plate tension command value) while more reliably suppressing the discrepancy between the plate tension command value 921 and the actual plate tension value 951.

[0180] Furthermore, in this embodiment, the looper control device 110, during the first compensation of the static friction force F0', compensates the static friction force F0' between the looper trolley 206 and the rail 208 with a static friction compensation amount T that has an absolute value greater than the absolute value of the difference between the maximum static friction force F0 between the looper trolley 206 and the rail 208 and the static friction force F0'. comp We calculate _1. Therefore, in the first compensation of static friction force F0', we can calculate a value that is relatively close to the compensation amount required to compensate for the maximum static friction force F0. Thus, the number of times n is compensated for static friction force F0' can be reduced.

[0181] In addition, various modifications described in the first embodiment may also be adopted in this embodiment. For example, as described in the first embodiment, a machine learning model may be used. In this case, for example, after the excitation current is output by the command unit 614, even if the actual drum torque value 931 becomes the drum torque command value 941, if the actual bogie speed value 961 is 0 (zero) and the looper bogie 206 is stationary, the looper control device 110 calculates a drum torque command value 941 that has a larger absolute value than the drum torque command value 941 already used to output the excitation current.

[0182] (Other embodiments) Furthermore, the embodiments of the present invention described above can be realized by a computer executing a program. A computer-readable recording medium on which the program is recorded, and a computer program product such as the program itself, can also be applied as embodiments of the present invention. Examples of recording media include flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, magnetic tapes, non-volatile memory cards, ROMs, etc. Moreover, embodiments of the present invention may be realized by a PLC (Programmable Logic Controller) or by dedicated hardware such as an ASIC (Application Specific Integrated Circuit). Furthermore, the embodiments of the present invention described above are merely examples of how the invention can be implemented, and the technical scope of the invention should not be interpreted as being limited by them. In other words, the present invention can be implemented in various ways without departing from its technical concept or its main features.

[0183] Furthermore, the disclosure of the above embodiments is as follows, for example. (Disclosure 1) A looper control device for controlling the tension of a strip of material in a loop storage device that temporarily stores a strip of material transported from an upper process facility and discharges it to a lower process facility, using a looper trolley that moves along a transport path to adjust the amount of the stored strip of material, The system includes an operation amount calculation unit that calculates an operation amount for controlling the tension, The looper control device includes an operation amount calculation unit which, when the tension setting value, which is the set value of the tension, is changed while the looper trolley is stationary, calculates a static friction-compensated operation amount to apply to the looper trolley an external force exceeding the maximum static friction force between the looper trolley and the travel path, as an operation amount for controlling the tension. (Disclosure 2) The manipulated amount calculation unit includes a static friction compensation unit that, when the tension setting value is changed, calculates a static friction compensation amount which is a compensation amount that makes the external force applied to the looper trolley greater than before the tension setting value was changed, as a compensation amount to compensate for the static friction force between the looper trolley and the travel path, A static friction compensation amount correction unit corrects the amount of control for controlling the tension calculated based on the changed tension setting value, based on the static friction compensation amount calculated by the static friction compensation unit, A looper control device according to disclosure 1, having the following features. (Disclosure 3) The static friction compensation unit includes a static friction force calculation unit that calculates the static friction force generated between the looper trolley and the movement path in response to the external force applied to the looper trolley, A static friction compensation amount calculation unit calculates the static friction compensation amount based on the maximum static friction force between the looper trolley and the movement path and the static friction force calculated by the static friction force calculation unit, A looper control device according to disclosure 2, having the following characteristics. (Disclosure 4) The looper control device according to disclosure 3, wherein the static friction compensation amount calculation unit calculates the static friction amount such that the static friction force between the looper trolley and the travel path is compensated by a friction force having an absolute value greater than the absolute value of the difference between the maximum static friction force between the looper trolley and the travel path and the static friction force calculated by the static friction force calculation unit. (Disclosure 5) The manipulated amount calculation unit has a command unit that generates a command value based on the manipulated amount for controlling the tension, The command unit generates a command value based on the static friction-compensated operating amount when the tension setting value is changed. The looper control device according to any one of disclosures 1 to 4, wherein the manipulated amount calculation unit calculates a static friction-compensated manipulated amount that is greater in absolute value than the static friction-compensated manipulated amount when the looper cart remains stationary even after a drive signal is output to the looper cart based on the command value and the actual value of the manipulated amount for controlling the tension becomes the static friction-compensated manipulated amount that is the source of the command value. (Disclosure 6) The manipulated amount calculation unit includes a static friction compensation unit that, when the tension setting value is changed, calculates a static friction compensation amount which is a compensation amount that makes the external force applied to the looper trolley greater than before the tension setting value was changed, as a compensation amount to compensate for the static friction force between the looper trolley and the travel path, A static friction compensation amount correction unit corrects the amount of control for controlling the tension calculated based on the changed tension setting value, based on the static friction compensation amount calculated by the static friction compensation unit, It has, The looper control device according to disclosure 5, wherein the static friction compensation unit calculates a static friction compensation amount that is larger in absolute value than the static friction compensation amount already calculated when the actual value reaches the command value and the looper trolley is stationary. (Disclosure 7) The static friction compensation unit is, A static friction force calculation unit calculates the static friction force generated between the looper trolley and the movement path in response to the external force applied to the looper trolley, A static friction compensation amount calculation unit calculates the static friction compensation amount based on the maximum static friction force between the looper trolley and the movement path and the static friction force calculated by the static friction force calculation unit, It has, The looper control device according to disclosure 6, wherein the static friction compensation amount calculation unit calculates the static friction compensation amount such that, during the first compensation of the static friction force between the looper trolley and the travel path, the static friction force between the looper trolley and the travel path is compensated by a friction force having an absolute value greater than the absolute value of the difference between the maximum static friction force between the looper trolley and the travel path and the static friction force calculated by the static friction force calculation unit. (Disclosure 8) The looper control device according to disclosure 2, 3, 4, 6, or 7, wherein the static friction compensation amount is a correction amount for the torque of the motor that drives the looper trolley. (Disclosure 9) The manipulated amount calculation unit includes a tension command calculation unit that calculates a tension command value which is the target value of the tension at each time based on the tension set value. The looper control device according to any one of disclosures 1 to 8, wherein the manipulated amount calculation unit calculates the static friction-compensated manipulated amount during the period from the timing when the tension setting value is changed to the timing when the tension command value becomes the changed tension setting value. (Disclosure 10) The looper control device according to disclosure 9, wherein the manipulated amount calculation unit starts calculating the static friction-compensated manipulated amount at the timing when the tension command value becomes a tension reference value which is the value obtained by dividing the tension set value before the change and the tension set value after the change by a predetermined internal division ratio, or at the timing when the tension set value is changed and the timing when the tension command value becomes the tension set value after the change are divided by a predetermined internal division ratio. (Disclosure 11) The looper control device according to any one of disclosures 1 to 10, wherein the manipulated amount calculation unit does not calculate the static friction-compensated manipulated amount when it obtains information indicating that the looper trolley has moved after the tension setting value has been changed. (Disclosure 12) A looper control device for controlling the tension of a strip of material in a loop storage device that temporarily stores a strip of material transported from an upper process facility and discharges it to a lower process facility, using a looper trolley that moves along a transport path to adjust the amount of the stored strip of material, The system includes a control amount calculation step for calculating a control amount for controlling the tension, The aforementioned operation amount calculation step is a looper control method in which, when the tension setting value, which is the set value of the tension, is changed while the looper trolley is stationary, a static friction-compensated operation amount is calculated as an operation amount for controlling the tension, which is used to apply an external force to the looper trolley that exceeds the maximum static friction force between the looper trolley and the travel path. (Disclosure 13) A program for causing a computer to function as a component of any one of the looper control devices described in Disclosures 1 to 11. [Explanation of Symbols]

[0184] 101 Payoffriel 102 Welding Equipment 103 Inlet Looper 104 Annealing Furnace 105 Plating equipment 106 Temper Rolling Mill 107 Outlet Looper 108 Cutting equipment 109 Tension Reel 110 Looper Control Device 201 Inlet Roll Motor 202 Bridle Roll 203 Looper Roll 204 Center Roll Motor 205 Center bridle roll 206 Looper Trolley 207 Looper Motor 208 rails 209 Tension Detector 210 Speed ​​detector 211 Torque Detector 212 Pulley 213 Wire 214 Drums 215 Bogie body 215a wheels 215b Mounting frame 216 Fixed end 411 Position of the looper trolley 412 Sync position 421 Plate tension command value 422 Drum Torque Actual Value 423 Actual values ​​of board tension 600 Operation amount calculation section 601 Department for Acquiring Operational Records 602 Unit for acquiring operational settings 603 Tension command calculation section 604 Tension Deviation Calculation Unit 605 PI Control Unit 606 Tension Addition Section 607 Torque Conversion Section 608 Static friction compensation section 608a Tension setting change determination unit 608b Vehicle speed determination section 608c Static friction force calculation section 608d Static friction compensation amount calculation section 609 Static friction compensation amount correction section 610 Mecha-Loss Compensation Department 611 Mechanical Loss Compensation Amount Correction Unit 612 Inertia compensation section 613 Inertia compensation amount correction section 614 Command Department 620 Line Management Computer 711, 911 Board tension setting values 721, 921 Plate tension command values 731~733, 931 Drum Torque Actual Values 741-743, 941 Drum Torque Command Values 751-753, 951 Board tension actual values 761-763, 961 Bogie Speed ​​Actual Values L s synchronized position F0 maximum static friction force F0' Static friction force F drum Drum tension F plate Plate tension FS board tension standard value F1: Board tension setting value before change F2 Changed board tension setting value t1 is the time to start reducing the input speed. t2 is the time to start increasing the input speed. The time when the t3 looper trolley begins moving towards the storage side. The time when the position of the T4 looper trolley returns to the synchronized position. t a Time when the board tension setting is changed t b The time at which the board tension command value becomes the changed board tension set value. t c The time to start calculating the current static friction force and correcting the reference torque based on the static friction compensation amount. t d Time when the actual drum torque value becomes the commanded drum torque value t e The time at which the actual board tension value becomes the commanded board tension value. T comp Static friction compensation amount T R Reference Torque T RF Torque after compensating for static friction T RFM Torque after compensation for static friction and mechanical losses T RFMI Torque after compensating for static friction, mechanical losses, and inertia

Claims

1. A looper control device for controlling the tension of a strip of material in a loop storage device that temporarily stores a strip of material transported from an upper process facility and discharges it to a lower process facility, using a looper trolley that moves along a transport path to adjust the amount of the stored strip of material, The system includes an operation amount calculation unit that calculates an operation amount for controlling the tension, The looper control device includes an operation amount calculation unit which, when the tension setting value, which is the set value of the tension, is changed while the looper trolley is stationary, calculates a static friction-compensated operation amount to apply to the looper trolley an external force exceeding the maximum static friction force between the looper trolley and the travel path, as an operation amount for controlling the tension.

2. The manipulated amount calculation unit includes a static friction compensation unit that, when the tension setting value is changed, calculates a static friction compensation amount which is a compensation amount that makes the external force applied to the looper trolley greater than before the tension setting value was changed, as a compensation amount to compensate for the static friction force between the looper trolley and the travel path, A static friction compensation amount correction unit corrects the amount of control for controlling the tension calculated based on the changed tension setting value, based on the static friction compensation amount calculated by the static friction compensation unit, A looper control device according to claim 1, having the following features.

3. The static friction compensation unit includes a static friction force calculation unit that calculates the static friction force generated between the looper trolley and the movement path in response to the external force applied to the looper trolley, A static friction compensation amount calculation unit calculates the static friction compensation amount based on the maximum static friction force between the looper trolley and the movement path and the static friction force calculated by the static friction force calculation unit, A looper control device according to claim 2, having the following features.

4. The looper control device according to claim 3, wherein the static friction compensation amount calculation unit calculates the static friction amount such that the static friction force between the looper trolley and the movement path is compensated by a friction force having an absolute value greater than the absolute value of the difference between the maximum static friction force between the looper trolley and the movement path and the static friction force calculated by the static friction force calculation unit.

5. The manipulated amount calculation unit has a command unit that generates a command value based on the manipulated amount for controlling the tension, The command unit generates a command value based on the static friction-compensated operating amount when the tension setting value is changed. The looper control device according to any one of claims 1 to 4, wherein the manipulated amount calculation unit calculates a static friction-compensated manipulated amount that is greater in absolute value than the static friction-compensated manipulated amount if the looper cart remains stationary even after the actual value of the manipulated amount for controlling the tension has reached the static friction-compensated manipulated amount that is the source of the command value, after a drive signal has been output to the looper cart based on the command value.

6. The manipulated amount calculation unit includes a static friction compensation unit that, when the tension setting value is changed, calculates a static friction compensation amount which is a compensation amount that makes the external force applied to the looper trolley greater than before the tension setting value was changed, as a compensation amount to compensate for the static friction force between the looper trolley and the travel path, A static friction compensation amount correction unit corrects the amount of control for controlling the tension calculated based on the changed tension setting value, based on the static friction compensation amount calculated by the static friction compensation unit, It has, The looper control device according to claim 5, wherein the static friction compensation unit calculates a static friction compensation amount that is larger in absolute value than the static friction compensation amount already calculated when the actual value reaches the command value and the looper trolley is stationary.

7. The static friction compensation unit is, A static friction force calculation unit calculates the static friction force generated between the looper trolley and the movement path in response to the external force applied to the looper trolley, A static friction compensation amount calculation unit calculates the static friction compensation amount based on the maximum static friction force between the looper trolley and the movement path and the static friction force calculated by the static friction force calculation unit, It has, The looper control device according to claim 6, wherein the static friction compensation amount calculation unit calculates the static friction compensation amount such that, in the first compensation of the static friction force between the looper trolley and the travel path, the static friction force between the looper trolley and the travel path is compensated by a friction force having an absolute value greater than the absolute value of the difference between the maximum static friction force between the looper trolley and the travel path and the static friction force calculated by the static friction force calculation unit.

8. The looper control device according to claim 2 or 3, wherein the static friction compensation amount is a correction amount for the torque of the motor that drives the looper trolley.

9. The manipulated amount calculation unit includes a tension command calculation unit that calculates a tension command value which is the target value of the tension at each time based on the tension set value. The looper control device according to any one of claims 1 to 4, wherein the manipulated amount calculation unit calculates the static friction-compensated manipulated amount during the period from the timing when the tension setting value is changed to the timing when the tension command value becomes the changed tension setting value.

10. The looper control device according to claim 9, wherein the manipulated amount calculation unit starts calculating the static friction-compensated manipulated amount at the timing when the tension command value becomes a tension reference value which is the value obtained by dividing the tension set value before the change and the tension set value after the change by a predetermined internal division ratio, or at the timing when the tension set value is changed and the timing when the tension command value becomes the tension set value after the change are divided by a predetermined internal division ratio.

11. The looper control device according to any one of claims 1 to 4, wherein the operation amount calculation unit does not calculate the operation amount after static friction compensation when it obtains information indicating that the looper trolley has moved after the tension setting value has been changed.

12. A looper control device for controlling the tension of a strip of material in a loop storage device that temporarily stores a strip of material transported from an upper process facility and discharges it to a lower process facility, using a looper trolley that moves along a transport path to adjust the amount of the stored strip of material, The system includes a control amount calculation step for calculating a control amount for controlling the tension, The aforementioned operation amount calculation step is a looper control method in which, when the tension setting value, which is the set value of the tension, is changed while the looper trolley is stationary, a static friction-compensated operation amount is calculated as an operation amount for controlling the tension, which is used to apply an external force to the looper trolley that exceeds the maximum static friction force between the looper trolley and the travel path.

13. A program for causing a computer to function as each part of the looper control device according to any one of claims 1 to 4.

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