KR20020052002A - The tuning apparatus of scale breaker parameter - Google Patents

Abstract

PURPOSE: An apparatus for adjusting parameters of a scale breaker is provided to reduce facility load by adjusting parameters of the scale breaker using a cascaded fuzzy controller, thereby appropriately setting elongation applied onto an intermesh of leveling unit and a strip and uniformly distributing loads on stretching motor and main motor. CONSTITUTION: The apparatus for adjusting parameters of a scale breaker comprises a material detection sensor(31) which is installed at the entrance side of the scale breaker to detect arrival of the material; an operation control computer(32) providing with information of the material including thickness, width and steel types of the material; a process computer(33) storing the set parameters in a parameter table form by setting parameters of the scale breaker after receiving material information from the operation control computer(32), renewing the parameters using new parameters provided with afterwards, and providing with set values of intermesh and elongation using the parameters; a program logic controller(34) controlling a stretching motor and an intermesh motor based on the set values of intermesh and elongation from the process computer(33); an overload detector(36) detecting overload of the stretching motor and intermesh motor; and a parameter controller providing the process computer(33) with the determined optimum parameters by performing fuzzy logic using load and load variation as input variables, thereby determining optimum parameters on the intermesh and elongation in case that overload is detected in the overload detector(36).

Description

Parameter breaker of scale breaker {THE TUNING APPARATUS OF SCALE BREAKER PARAMETER}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a parameter adjusting device for a scale breaker, and in particular, by adjusting a parameter of a scale breaker facility for removing scales on the surface of a hot rolled steel sheet during a cold rolling process in a steel mill by using a cascaded fuzzy controller. It is possible to optimally set the elongation given to the intermesh and strip of the leveling unit of the leveling unit, and the uneven load applied to the stretching motor and the main motor, which are the load facilities. The present invention relates to a parameter breaker for a scale breaker capable of equally distributing the weight, thereby reducing the load on the equipment.

In general, in the cold rolling process, various pickling facilities are used to remove iron oxide formed on the hot rolled steel sheet surface.

1 is a schematic diagram of a system before and after a general scale breaker, and FIG. 2 is a schematic view of the scale breaker of FIG. 1.

Referring to FIG. 1, when the steel sheet (material, hot coil: 01) arrives at the scale breaker 03 through the scale breaker entrance bridle roll 02, as shown in FIG. 2, the upper and lower work rolls 15, 16, and 17 may be used. The surface oxide layer is finely crushed by the bending stress between and 18, and then proceeds to the hydrochloric acid tank which is a post-process through the exit bridal roll 04. At this time, the entry and exit side tension bridal roll (02,04) has a function to impart a tensile stress to the steel sheet (01).

The motor driving force generated by the main motor (main motor) 05 advances the steel plate 01 by driving the exit bridal roll 04 via the # 1 gear 06 and the # 2 gear 07. On the other hand, the driving force of the main driver (05) is reduced by the amount corresponding to the elongation (0 to 3%) due to the reverse driving force of the stretching motor (09) in the differential gear for controlling the elongation (08) # 3 gear (10 ) And # 4 gear 11 are passed to the entrance bridal roll 02. Therefore, the entry bridle roll 02 moves at a rate of about 0 to 3% slower than the exit bridal roll 04, and thus a tensile stress is applied to enable the stretching of the steel sheet 01.

However, since it is difficult to obtain a desired elongation rate only by the reverse driving force of the stretching driver 09, the intermeshing rolls of the upper and lower work rolls 15, 16, 17, 18 of the # 1, 2 leveling units 12, 13 of FIG. Overlap amount: 0 ~ 30mm) to increase the stretching.

3 is an explanatory diagram of an intermesh in a leveling unit. Referring to FIG. 3, the meaning of an intermesh may be understood. The # 3 leveling unit 14 is for shape correction and does not affect the elongation. The upper work roll is fixedly positioned at a predetermined position by the hydraulic cylinders 19 and 20, and the lower work roll is to adjust the intermesh while moving up and down by the intermesh motors 21 and 22. As the intermesh increases, the load of the stretch driver 09 decreases, but the load increases on the main driver 05. On the contrary, as the intermesh decreases, the load of the stretching driver 09 increases, and the load of the main driver 05 decreases.

In addition, as the elongation is set higher, the load of the main driver decreases, but the load of the elongated driver is increased, and if it is set lower, the load is reversed, but below a certain value, the oxide layer fracture is insufficient, causing pickling quality defects. Increasing the line speed with the parameter fixed increases the load on both the main and extension drivers.

For stable operation under these variable conditions, the parameter setting table can be obtained only after extensive application tests for the width, thickness, and steel grade of the hot coil at the initial installation of the scale breaker. However, it is very difficult to test for a wide range of widths, thicknesses and steel grades, and the setpoints obtained within the ranges available are intuitive and average values, which makes them suitable for different thickness / material differences and new steel grade materials. Setting up is very hard. This causes excessive load on the main driver or the extension driver, which is the main cause of equipment trouble.

4 is a configuration diagram of a parameter adjusting device of a conventional scale breaker. Referring to FIG. 4, when the material top part arrives 31 at the scale breaker entrance side, general information on the material from the operation management computer B / C: 32 ( Thickness, width, steel grade) are provided to a process computer (SCC: 33). Based on the material information, # 1,2 intermesh setting values and elongation setting values are transmitted from the scale breaker parameter setting table stored in the process computer to the scale breaker PLC 34. The intermesh motors 21 and 22 are then operated for the # 1 and 2 intermesh adjustments 35 and the draw driver 09 is operated for the elongation adjustment 35. During the operation of the facility, the loads of the main driver and the extension driver are continuously fed back (36), and if an overload occurs, an alarm is generated (38) to allow the driver to manually operate (39).

That is, the driver works by arbitrarily lowering the intermesh and elongation. Alternatively, a certain amount of intermesh and elongation are automatically lowered uniformly, but this is implemented as a concept of temporary emergency measures, and since the consistency cannot be confirmed, the driver's manual operation is inevitable. When the top portion of the trailing material arrives 50, the block diagram of FIG. 3 is redone.

Scale breakers are relatively complicated and sophisticated in their internal installations. And the control inputs can be clearly seen when blowing only on the system itself, but the control modeling of the system is difficult because the output is not stable over time and the results are difficult to quantify. In this case, intelligent control techniques are often used.

However, in the case of genetic algorithm control or neural network control, it is possible to converge to the correct value, but it is not suitable for the continuous pickling line where the work is performed at high speed because it takes relatively long time to converge the value. On the other hand, the fuzzy controller has a fast response speed and can manage parameters using a table, so that a table can be obtained by obtaining a relatively accurate value in a high speed line.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and therefore, an object of the present invention is to provide a cascaded fuzzy controller with a parameter of a scale breaker facility for removing scale on the surface of a hot rolled steel sheet during a cold rolling process in a steel mill. By adjusting using, the elongation given to the intermesh and strip of each leveling unit can be optimally set, and the stretching motor and main driver, which are the load equipments, can be set optimally. The present invention provides a scale breaker parameter adjusting device capable of equally distributing non-uniform loads on a motor and reducing equipment load.

1 is a system configuration diagram before and after a general scale breaker.

FIG. 2 is a schematic diagram of the scale breaker of FIG. 1

3 is an explanatory diagram of an intermesh in a leveling unit.

4 is a configuration diagram of a parameter adjusting device of a conventional scale breaker.

5 is a configuration diagram of a parameter adjusting device for a scale breaker according to the present invention.

6A-6C are a graph of a stretch driver load control fuzzy membership function.

7A-7C are graphs showing the main driver load control fuzzy membership function.

8A-8C are load change control fuzzy membership function graphs.

Explanation of symbols on the main parts of the drawings

01: Material (steel plate, hot coil) 02: Entry tension bridal roll

03: scale breaker 04: exit tension bridal roll

05: main motor 06: # 1 gear

07: # 2 Gear 08: Differential Gear for Elongation Control

09: stretching motor 10: # 3 gear

11: # 4 gear 12,13,14: # 1, # 2, # 3 leveling unit

15,16: # 1 leveling unit upper and lower work roll

17,18: Upper and lower work roll of # 2 leveling unit

19,20: Hydraulic cylinder of upper part of # 1,2 leveling unit

31 ~ 42: Block Diagram Description

As a technical means for achieving the above object of the present invention, the apparatus of the present invention is installed at the scale breaker entrance side to detect the arrival of the material; Operation management computer for providing information of the material, including the thickness, width, steel grade of the material; Receiving the input of the material information from the operation management computer to set the parameters of the scale breaker to save in the form of a parameter table, and then to update the parameters with the provided parameters, using these parameters to provide the intermesh set value and elongation set value Process computer; A program logic controller for controlling the stretching driver and the intomesh motor based on the intermesh set value and the elongation set value from the process computer; An overload detector for detecting an overload of the extension driver and the intomesh motor; A parameter controller which, when an overload is detected by the overload detector, performs the fuzzy inference using the load and the load variation as an input variable to determine the optimal parameters for the intermesh and the elongation and provide them to the process computer; Characterized by including.

EMBODIMENT OF THE INVENTION Hereinafter, the scale breaker apparatus which concerns on this invention is demonstrated in detail with reference to attached drawing. In the drawings referred to in the present invention, components having substantially the same configuration and function will use the same reference numerals.

FIG. 5 is a configuration diagram of a parameter adjusting device for a scale breaker according to the present invention. Referring to FIG. 5, the scale breaker device according to the present invention is installed at the inlet of the scale breaker and detects the arrival of a material. And an operation management computer 32 for providing information of the material including the thickness, width, and steel grade of the material, and receiving the material information from the operation management computer 32 to set parameters of the scale breaker in the form of a parameter table. A process computer 33 for storing and updating parameters with the provided parameters, and providing intermesh set values and elongation set values using these parameters, and intermesh set values and elongation values from the process computer 33. A program logic controller 34 for controlling the stretching driver and the intomesh motor based on the set value, and the stretching driver and the intomesh motor. When the overload detector 36 and the overload detector 36 detect an overload, fuzzy inference using the load and the load change amount as an input variable is performed to determine the optimal parameters for the intermesh and the elongation. And a parameter controller 40 which provides the process computer 33.

The parameter controller 40 uses the load amount and the load change amount of the main driver and the extension driver of the scale breaker as input variables, normalizes this input variable to correspond to the fuzzy variable, and then performs fuzzy inference according to the fuzzy rule. In addition, it includes a multi-step fuzzy controller that performs a series of processes to be attenuated.

6A-6C are graphs of a stretch driver load control fuzzy membership function, FIGS. 7A-7C are graphs of a main driver load control fuzzy membership function graph, and FIGS. 8A-8C are graphs of a load change control fuzzy membership function graph.

Operation according to the device (circuit) of the present invention configured as described above will be described in detail below based on the accompanying drawings.

The present invention is a multi-stage in setting the intermesh and elongation, which are the main parameters of a scale breaker facility that performs a mechanical pickling role in a continuous pickling line entry facility of a cold rolling process. A cascaded fuzzy controller was applied. Accordingly, in order to find the optimal parameters, fuzzy controllers are installed in multiple stages to identify membership functions to be used for each controller, and the parameters are continuously fine-tuned while being applied to actual work through the process management computer (SCC). To do that.

A parameter adjusting method of the scale breaker according to the present invention will be described with reference to FIGS. 5 to 8.

Referring to Fig. 5, first, when a material detecting sensor 31 detects that a material to be pickled enters the scale breaker, the process control computer SCC 33 is moved from the operation management computer B / C 32. The material information (thickness, width, steel grade) is received. At this time, the process control computer 33 reads the setting values of the # 1 intermesh, the # 2 intermesh and the elongation from the parameter setting table input in advance. Each parameter is then adjusted accordingly. These values, which are initially read, are used as initial reference values for parameter conversion.

If the process control computer 33 instructs the control of the main driver and the stretching driver while providing the set values of the # 1 intermesh, the # 2 intermesh and the elongation to the program logic controller 34, the program accordingly The tissue controller 34 controls the operations of the main driver and the stretching driver according to the set values of the # 1 intermesh, the # 2 intermesh and the elongation provided.

Next, the overload detector 36 detects the load value and the change amount of the load value applied to the respective equipments from the main driver and the stretching driver, and provides the overload detection signal to the parameter controller 40, and the parameter controller 40. After the load and incubation variation from the overload detector 36 are input variables, the input variable is normalized to correspond to a fuzzy variable, and then fuzzy inference is performed according to a fuzzy rule to determine an output variable. Optimal parameters are output through a series of fuzzy processes that make the output variable according to

Accordingly, the input variable of the load determines the optimum parameter for the elongation change and the intermesh value by the load control fuzzy membership function, that is, the fuzzy rule, for the elongate actuator as shown in FIGS. 6A, 6B and 6C. Referring to FIG. 6A, for example, a load among input variables is converted into a fuzzy variable with a value of approximately 50-120 as shown in FIG. 6A, and the fuzzy rule such as the membership function shown in FIG. 6A is converted into a fuzzy variable. By determining the output variable accordingly and unpurging the output variable, it is possible to freeze the set value of the elongation. 7 and 8, the load of the main driver and the incubation amount of the main driver are received as input variables, and the output value, that is, the elongation of the main driver and the set value of the intermesh are set through the same process as the operation of the fuzzy controller described above. You can get it.

Further, for the main driver as shown in Figs. 7A, 7B and 7C, the elongation change and the intermesh value can be determined as the optimum parameters by the load control fuzzy membership function, i.e., the fuzzy rule. As the input variable of the load change amount, an elongation change and an intermesh value can be determined as optimal parameters by the load control fuzzy membership function as shown in FIGS. 8A, 8B and 8C.

When the parameter controller 40 provides the above-described parameters to the process control computer 33, the process control computer 33 adjusts the parameters again.

The modified parameter is inputted to the previously set table and immediately changes the actual parameter value of the scale breaker. Then, the load of the facility and the load change are read again to change the existing parameter value. In this way, the optimal parameter value is found repeatedly. In other words, the process described above is repeated to find appropriate parameters for materials of different grades, thicknesses, and widths.

As can be seen from the above, the membership function of the fuzzy controller in the present invention is the most important factor in determining the actual parameter value. The criteria for setting membership function of fuzzy controller are as follows. It also indicates the effect of intermesh and elongation on the installation.

When the intermesh is increased, the load of the stretching driver 09 to make a certain amount of elongation is reduced. This is because the amount of bending received from the work roll increases due to the natural tensile stress. However, as the contact area between the work roll of the scale breaker and the surface of the material increases, the contact angle naturally increases. This increases the tension required to advance the material. Therefore, in order to advance the material at a predetermined speed, a lot of driving force is required, and thus the load of the main driver increases. Reducing the amount of intermeshes is the opposite.

Moreover, when elongation becomes large, the speed difference of the entry side and exit side of a scale breaker becomes large. In such a case, the tension of the strip is reduced because the speed of the ring gear of the differential gear 08 increases and the speed of the side tension bridal roll 02 decreases. Thus, the load of the main driver 05 is reduced. On the other hand, the load of the stretching driver 09 is increased.

As can be seen from the load control purge membership function of FIG. 6 and FIG. 7, the control is performed by considering the point where the facility load is 75% as the load proper point. For stable distribution of the load, the parameter value is modified when more or less load is applied. Also, the # 1 intermesh parameter is set to 4 mm, and the # 2 intermesh parameter is set to vary within a range not exceeding 2 mm. This is because the effect of the # 1 leveling unit is great. Further abrupt parameter changes can cause impulse vibrations in the installation, resulting in defects such as chattering marks on the material surface.

In addition, the parameter adjustment of the elongation is also made within the range not to exceed 0.4%. This is because when the elongation changes abruptly, the speed of the entrance is rapidly decelerated or rapidly accelerated, so that hunting is caused in the tension bridle roll 02 and the differential gear 08 at the entrance by inertia.

In addition, since the actuator has a mass moment of inertia larger than that of other facilities, it is necessary to additionally install another purge controller to cope with fluctuations in the installation load. The load variation control fuzzy membership function of FIG. 8 is a membership function that copes with load variation. In other words, if the load of the equipment is rapidly increasing, even if the load does not reach 100%, the parameter must be adjusted to prevent the driver from tripping. Note that the load control fuzzy membership function and input are different.

When the above two purge controllers are configured in multiple stages, and the controller is installed in this way, it is possible not only to protect the equipment, but also to obtain a satisfactory pickling quality by applying an appropriate load.

According to the present invention as described above, by installing a multi-stage purge controller in a way of modifying the parameters of the scale breaker, it is possible to almost eliminate the errors caused when the parameters are manually modified in the past, the facility itself loads without operator intervention To find the optimal parameters for the facility, to ensure the proper performance of the facility as well as to protect the facility, and to prevent tripping of the motor, reducing the number of breakdowns of the facility and ensuring the pickling quality desired by the demand. There is an effect.

The above description is only a description of one embodiment of the present invention, the present invention is capable of various changes and modifications within the scope of the configuration.

Claims (2)

A material detecting sensor 31 installed at the scale breaker entrance and detecting the arrival of the material; Operation management computer 32 for providing information of the material, including the thickness, width, steel grade of the material; Receives input of the material information from the operation management computer 32, sets the parameters of the scale breaker, stores them in the form of a parameter table, and then updates the parameters with the provided parameters, and sets the intermesh set values and elongation set values using these parameters. Process computer 33 for providing a; A program logic controller 34 for controlling the stretching driver and the intomesh motor based on the intermesh set value and the elongation set value from the process computer 33; An overload detector 36 for detecting an overload of the extension driver and the intomesh motor; When an overload is detected in the overload detector 36, a parameter controller is provided to the process computer 33 to determine an optimal parameter for the intermesh and the elongation by performing fuzzy inference using the load and the load variation as input variables. 40); Parameter adjustment apparatus of the scale breaker, characterized in that it comprises a. The method of claim 1, wherein the parameter controller 40 A fuzzy controller that loads and loads changes on the main and extension drivers of the scale breaker as the input variables, normalizes these input variables to correspond to the fuzzy variables, performs fuzzy inference according to the fuzzy rules, and then debuffs them. Parameter adjustment apparatus for a scale breaker, characterized in that it comprises a multi-step.