Control device, control method, and control system

Abstract

To provide a control device, a control system, a control method, and a program capable of creating a control system further appropriate to the control object.SOLUTION: A control device includes: a control object state quantity grasping device 601 which grasps a state quantity of a previously determined control object 500, and detects an abnormality of the state quantity of the control object from an operation record of the control object 500; a control object analysis device 701 which estimates correlation between state quantities of the control object 500, and determines types of the input state quantity, output state quantity, and the control system which are necessary to perform control of the control object 500; and a control system designing device 702 which sets a transfer function being a time response of the control object 500 and sets a control parameter of the control system.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a control device, a control method, and a control system, and more particularly to a control device to which various control systems can be applied. [Background technology]

[0002] Various control methods are used to control industrial plants and other controlled objects in order to improve product quality, operational efficiency, etc. A control method is not always optimal for all conditions of the industrial plant being controlled, but is often optimal under specific conditions. Since the conditions of industrial plants are constantly changing, it is necessary to prepare multiple control methods even for the same control purpose and change the control method according to the condition of the industrial plant. In addition, by developing and applying new control methods to improve control performance, further improvement in product quality and operational efficiency can be expected.

[0003] Generally, in industrial plants, the control of one control object is handled by a single manufacturer, so when another manufacturer develops a new control method, it is difficult to apply it. Therefore, the control in industrial plants is often not at its best at that point in time. As an industrial plant, for example, a rolling mill that rolls a metal plate, which is a material to be rolled, is known. The rolling mill uses a tension reel to send out and wind up the material to be rolled, and rolls the unwound material by passing it between a pair of rolls. For example, a plate thickness control that controls the distance between a pair of rolls and a tension control that controls the speed of the tension reel (actually, the current of an electric motor) have been conventionally applied to such a rolling mill. However, under certain rolling conditions, a control system such as a plate thickness control that adjusts the speed at which the material to be rolled is sent out from the tension reel and a tension control that controls the distance between the pair of rolls has a higher control effect, so it has been proposed to maximize the control effect by switching between the two (for example, see Patent Document 1). Furthermore, when rolling an extremely thin material such as a foil, it has been proposed to control the rolling speed by using the thermal expansion of the rolls (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-113629 A [Patent Document 2] JP 2020-104165 A Summary of the Invention [Problem to be solved by the invention]

[0005] The controlled object is, for example, a plant capable of manufacturing various products, and the state of the controlled object changes depending on the product being manufactured and the operating conditions (the mechanical conditions of the plant, such as the manufacturing speed and manufacturing temperature). When the state of the controlled object changes, it is necessary to change the control method accordingly. There are control methods (proportional control, integral control, etc., combinations of state quantities and control operation terminals, etc.) as a method of change, and further, there are control gains for each control method. By changing the control system according to the state of the controlled object, it is possible to improve the value of the products manufactured in the controlled plant and to improve manufacturing efficiency. For this reason, new control methods are constantly being developed. When developing a new control method, a control engineer analyzes the problem in response to requests such as improving the product accuracy of the controlled plant, selects detectable state quantities of the controlled object from a state quantity detection device, selects an operating end for operating the selected state quantity from an operating end actuator, and designs the relationship between the state quantity and the operating end as the control system-i of the control device, etc. When designing a control system, it is necessary to take into account the dynamic characteristics (time response characteristics) between the operating end and the state quantity and ensure that the control system is stable. This work was previously performed by control engineers, but it is necessary to analyze the performance data of the controlled plant and carry out design work for the control system, which places a heavy burden on the engineers. It is also necessary to verify the effectiveness of the new control system, adjust the optimal control gain, and verify the range of state quantities of the control target that can be used. Furthermore, when applying a new control method, it is necessary to analyze the controlled object, design the control system based on the results, and then, depending on the purpose of the control method (e.g., whether it is effective when the controlled object is in a certain state), apply it on a trial basis while observing the state of the controlled object, and adjust the control method while assessing its effectiveness.Currently, these tasks are performed by people while checking the state of the controlled object, which is labor-intensive work. An object of the present invention is to provide a control device, a control method, and a control system that are capable of creating a control system that is more suitable for a controlled object. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention provides a control device that includes an acquisition means for acquiring a predetermined state quantity of a controlled object, a detection means for detecting an abnormality in the state quantity of the controlled object based on the operating performance of the controlled object, a determination means for estimating a correlation between the state quantities of the controlled objects and determining an input state quantity, an output state quantity and a type of control system required to control the controlled object, and a setting means for setting a transfer function which is a time response of the controlled object and control parameters of the control system.

[0007] The present invention also provides a control method, which acquires a predetermined state quantity of a controlled object, detects an abnormality in the state quantity of the controlled object based on an operational performance of the controlled object, estimates a correlation between the state quantities of the controlled object, determines input state quantities, output state quantities and a type of control system required for controlling the controlled object, and sets a transfer function which is a time response of the controlled object and control parameters of the control system.

[0008] Furthermore, the present invention is a control system having a predetermined controlled object and a control device that selects a control system to be applied to the controlled object, wherein the control device is equipped with an acquisition means for acquiring a state quantity of the controlled object, a detection means for detecting an abnormality in the state quantity of the controlled object from the operating performance of the controlled object, a determination means for estimating a correlation between the state quantities of the controlled objects and determining an input state quantity, an output state quantity and a type of control system required to control the controlled object, and a setting means for setting a transfer function which is a time response of the controlled object and control parameters of the control system. Effect of the Invention

[0009] According to the present invention, it is possible to provide a control device, a control method, and a control system that are capable of creating a control system that is more suitable for a controlled object, as compared to a case in which this configuration is not adopted. [Brief description of the drawings]

[0010] [Figure 1] 1 is a conceptual diagram showing an overall configuration of a control system according to a first embodiment. [Diagram 2] FIG. 1 illustrates an example of a control system for a controlled object. [Diagram 3] 1A is a conceptual diagram showing the configuration of a controlled object, and FIG. 1B is a diagram showing the definition of a transfer function. [Figure 4] FIG. 2 is a diagram showing the relationship between a control target, FF control, and FB control. [Diagram 5] FIG. 2 is a block diagram showing a functional configuration of a control system according to the present embodiment. [Figure 6] FIG. 2 is a diagram illustrating an example of a transfer function of a controlled object. [Figure 7] FIG. 13 is a diagram showing an example of a control target influence DB. [Figure 8] 11 is a diagram showing an example of a control object characteristic DB and a control system template DB. FIG. [Figure 9] FIG. 1 is a diagram showing a procedure for automatically designing a control system. [Figure 10] FIG. 10 is a diagram showing an example of a control system created by the procedure shown in FIG. [Figure 11] FIG. 10 is a diagram showing an example of a control system created by the procedure shown in FIG. [Figure 12] FIG. 2 is a conceptual diagram showing in more detail the overall configuration of the control system shown in FIG. [Figure 13] 13 is a diagram showing the contents of data registered in a registration control system DB. FIG. [Figure 14] 13 is a diagram showing the contents of data registered in a control system selection DB. FIG. [Figure 15] 1 is a diagram showing an operation flow of the control system when a control target is controlled using a general-purpose control system 6 or a registered control system. [Figure 16] FIG. 2 is a diagram showing an overview of the processing performed by the registration control system execution device. [Figure 17] 13 is a diagram showing input data and output data registered in a registered control system DB for each registered control system. FIG. [Figure 18] FIG. 11 is a schematic diagram showing a control system according to a second embodiment. [Figure 19] FIG. 1 is a diagram showing input (disturbance), input (operation amount), and output (state amount) when the controlled object is replaced with a rolling mill. [Figure 20] FIG. 13 is a diagram showing a change in shape of a rolled material due to a change in vendor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first and second embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0012] [First embodiment] Here, first, a first embodiment of a control system S to which the present embodiment is applied will be described. In the first embodiment, the control system S has a controlled plant 510, which is a general industrial plant, as a controlled object 500. A case will be described in which a control device 511 provided in the control system S selects a control system 501 to be applied to the controlled plant 510 from a general-purpose control system 614 and registered control systems 615B to 615Z. Note that, hereinafter, when there is no need to distinguish between the registered control systems 615B to 615Z, they may be simply referred to as registered control systems 615.

[0013] <Explanation of the overall configuration of the control system S> FIG. 1 is a conceptual diagram showing the overall configuration of a control system S in the first embodiment. Generally, plant control is performed by a control system 501 performing control calculations using the deviation between the state quantity and command value of a control object 500, and giving a control command to the control object 500. The control object 500 has multiple types of state quantities and control operation terminals, and the control system 501 performs control by combining them. Here, "state" refers to the state of the controlled object 500 itself and the state of the product manufactured by the controlled object 500. Examples of the state of the controlled object 500 itself include the operating speed and operating temperature. Also, the state of the product manufactured by the controlled object 500 includes, for example, the temperature and dimensions of the product. If the controlled object 500 is a rolling mill that manufactures rolled steel plates, the state of the product includes the thickness of the rolled steel plates. The "state quantity of the controlled object 500" is a numerical representation of this state. The "control operation end of the controlled object 500" is the part of the controlled object 500 that accepts control commands.

[0014] The controlled object 500 is, for example, a controlled plant 510 described later, which is an industrial plant capable of manufacturing various products. In the controlled object 500, the above-mentioned state changes depending on the product to be manufactured and the operating conditions. The "operating conditions" are, for example, mechanical conditions of the industrial plant, such as the manufacturing speed and the manufacturing temperature. When the state of the controlled object 500 changes, the control system 501 changes the control method accordingly. Examples of the change in the control method include a change in the control method itself, as well as a change in the control gain. Examples of the change in the control method itself include a combination of proportional control, integral control, and differential control, and a change in the combination of a state quantity and a control operation terminal. By changing the control method according to the state of the control target 500, it is possible to improve the value of the product manufactured by the control target 500 and improve manufacturing efficiency. For this reason, manufacturers are constantly developing control systems 501 that provide new control methods.

[0015] FIG. 2 is a diagram showing an example of a control system 501 for a control target 500. As shown in FIG. The output (state quantity) 803 of the controlled object 500 changes due to an input (disturbance) 801 and an input (operation quantity) 802. Here, the input (disturbance) 801 is a change in an external factor that affects the controlled object 500, and includes a change that can be detected by a state quantity detection device 513 of the controlled plant 510. The input (operation quantity) 802 can artificially change the output (state quantity) 803 of the controlled object 500. Although the output (state quantity) 803 changes due to the input (disturbance) 801, this can be countered by changing the input (operation quantity) 802. There are also cases where the input (operation quantity) 802 is changed in order to change the output (state quantity) 803 from one state to another.

[0016] If the influence of the input (disturbance) 801 on the output (state quantity) 803 is known, it is possible to detect the change in the input (disturbance) 801 and predict the change in the output (state quantity) 803. Then, by changing the input (operation quantity) 802, it is possible to keep the output (state quantity) 803 constant. This is done by FF (feedforward) control 804. Since not all of the input (disturbance) 801 can be detected, unpredictable changes occur in the output (state quantity) 803. For this reason, FB (feedback) control 805 changes the input (operation quantity) 802 in response to the change in the output (state quantity) 803, thereby suppressing the change in the output (state quantity) 803. By employing FF control or FB control as a control system, the accuracy of control of the controlled object 500 is improved.

[0017] There are a plurality of types of input (disturbance) 801, input (operation amount) 802, and output (state amount) 803, each of which has a different influence. For example, if a change in input (disturbance) 801(a) causes a large change (great influence) in output (state quantity) 803(a), and it is known that input (operation quantity) 802(b) causes a large change in output (state quantity) 803(a), then FF control 804 is used, which uses input (disturbance) 801(a) as input and outputs to input (operation quantity) 802(b). This makes it possible to suppress the influence of input (disturbance) 801(a) on output (state quantity) 803(a). Furthermore, when the output (state quantity) 803(b) changes significantly due to the input (operation quantity) 802(n), FB control 805 is used to change the input (operation quantity) 802(n) in response to the change in the output (state quantity) 803(b), thereby making it possible to suppress the change in the output (state quantity) 803(b).

[0018] FIG. 3A is a conceptual diagram showing the configuration of the controlled object 500. As shown in FIG. 3(A), the controlled object 500 is composed of a controlled plant 510, an actuated end actuator 512 for providing an input (actuated variable) 802 to the controlled plant 510, a disturbance transfer 514 which is a time response until an input (disturbance) 801 affects the controlled plant 510, and a state quantity detector 513 for detecting a state quantity of the controlled plant 510. The actuated end actuator 512, the state quantity detector 513, and the disturbance transfer 514 are determined by the mechanical configuration of the controlled object 500 and the electrical and mechanical responses of the machinery used, and the transfer functions which are time responses can be known in advance. Therefore, these transfer functions can be considered to be fixed.

[0019] In this embodiment, transfer functions corresponding to the controlled plant 510, the actuated end actuator 512, the disturbance transfer 514, and the state quantity detector 513, and representing the time response of each, are defined as shown in Fig. 3(B). The controlled plant transfer function G(S) 810 is a transfer function meaning the time response to the controlled object. The actuated end actuator transfer function A(S) 812 is a transfer function meaning the time response to the manipulated variable. The state quantity detector transfer function M(S) 813 is a transfer function meaning the time response to the state quantity detector 513. The disturbance transfer transfer function D(S) 814 is a transfer function meaning the time response to the disturbance. By setting such transfer functions to match the time response of the actual controlled object, the accuracy of control of the controlled object 500 can be improved.

[0020] Although the controlled plant transfer function G(S) 810 changes depending on the state of the controlled plant and the product being manufactured, the end effector actuator transfer function A(S) 812, the state quantity detector transfer function M(S) 813, and the disturbance transfer transfer function D(S) 814 are specific to the controlled plant 500 and can be investigated in advance by experiments, etc. Therefore, these transfer functions can be considered to be known. In other words, the end effector actuator transfer function A(S) 812, the state quantity detector transfer function M(S) 813, and the disturbance transfer transfer function D(S) 814 are determined in advance by the characteristics of the controlled plant 500. In this case, it becomes easier to set the transfer functions. Therefore, if the control target plant transfer function G(S) 810 can be obtained, the transfer function of the control target 500 can be estimated.

[0021] FIG. 4 is a diagram showing the relationship between the control target 500, the FF control 804, and the FB control 805. As described above, if the transfer function G(S) 810 can be estimated, each control can be designed. Here, design means determining the following control parameters for each control so that each control is stable in terms of control theory. In this case, the control parameters include the gain of at least one of FF (feedforward) control and FB (feedback) control. This allows settings that make it easy to demonstrate the functions of FF control or FB control when performing the control.

[0022] For FF control Conversion gain C: Coefficient for converting input (disturbance) 801 to input (operation amount) 802 Control Gain K FF : A coefficient for stably executing the FF control 804 Wasted time T FF : Coefficient for correcting disturbance transfer function 814

[0023] In case of FB control Conversion gain C: Coefficient for converting output (state quantity) 803 to input (operation quantity) 802 Control Gain K P : Coefficient for stable proportional control Control Gain K I : Coefficient for stable integral control

[0024] Various methods for designing the FF control 804 and the FB control 805 are described in known documents, so a description thereof will be omitted. Although the FF control 804 and the FB control 805 have been described here, it is also possible to set the FB control 805 as proportional control or proportional-integral-derivative control, or to apply optimal control by setting a template for the control system in advance. By defining in advance control templates such as FF control 804 and FB control 805 and a method of setting each of the above control parameters according to the transfer function of the controlled object 500, the design work can be automated.

[0025] <Explanation of how to automate the design work of control systems> Next, a method for automating the design work of a control system will be described below. FIG. 5 is a block diagram showing the functional configuration of a control system S according to the present embodiment. The control system S of this embodiment includes a control object analysis device 701 , a control system design device 702 , a control system registration device 703 , a control object characteristic DB (database) 711 , a control system template DB 712 , and a control object influence DB 713 . The controlled object analysis device 701 estimates the transfer function 810 of the controlled object 500, particularly the controlled object plant 510. Since the state of the controlled object 500 changes depending on the operating state (operating mode, operating speed, type of product, etc.) of the controlled object 500, it is necessary to estimate the controlled object plant transfer function 810 according to the operating state.

[0026] The control system design device 702 performs the design work of the control system after the analysis by the controlled object analysis device 701 is completed. The control system design device 702 extracts combinations with a large relationship from the relationship between a plurality of inputs (disturbances) 801 and inputs (operating variables) 802 and the relationship between a plurality of outputs (state variables) 803 and inputs (operating variables) 802, and selects a template control system (FF control, FB control, etc.) from the control system template DB 712 for the combination. Furthermore, the control system design device 702 estimates the transfer function of the controlled object 500 from the controlled object plant transfer function 810 estimated by the controlled object analysis device 701, and the operation end actuator transfer function A(S) 812, the state variable detection device transfer function M(S) 813, and the disturbance transfer transfer function D(S) 814 registered in advance in the controlled object characteristic DB 711, and determines the control parameters required for the template of the selected control system.

[0027] The control system registration device 703 registers the new control system created by the control system design device 702 in the registered control system DB 605 and the registered control system 615 .

[0028] As an example of automatic design of a control system, the following items are assumed for the controlled object 500. Each transfer function can be approximated by dead time plus first-order lag. The control target plant transfer function 810 is a physical phenomenon of the control target 500, so the dead time and the time constant of the first-order lag are smaller than those of the others. As a result, the control target plant transfer function 810 has a conversion gain G G In this case, the controlled plant transfer function 810 can be expressed in a simpler manner while maintaining accuracy. The disturbance transfer function 814 is considered to be a time delay until the input (disturbance) 801 reaches the controlled plant 510 from the disturbance source, and the first-order lag time is considered to be negligible.

[0029] FIG. 6 is a diagram showing an example of a transfer function of the controlled object 500 obtained based on the above assumptions. The transfer functions illustrated in FIG. 6 exist for each of a plurality of types of input (disturbance) 801, input (operation amount) 802, and output (state amount) 803.

[0030] In the controlled object analysis device 701, correlations between each type of input (disturbance) 801 of the controlled object 500 and each type of output (state quantity) 803 of the controlled object 500, and between each type of input (operation quantity) 802 of the controlled object 500 and each type of output (state quantity) 803 of the controlled object 500 are obtained using actual data for the controlled object 500. The correlations can be obtained by taking similarities in time-series movements using time-series actual data, or by determining whether the output (state quantity) 803 varies when the input (operation quantity) 802 varies. These are stored in the controlled object influence DB 713 as the variation ratio (degree of influence) of the output (state quantity) 803 relative to the variation of the input (operation quantity) 802 and the variation ratio (degree of influence) of the output (state quantity) 803 relative to the variation of the input (disturbance) 801.

[0031] FIG. 7 is a diagram showing an example of the control target effect DB 713. As shown in FIG. 7 includes the state of the controlled object 500 with respect to the input (operation amount) 802 and the output (state amount) 803. This controlled object influence DB 713 also includes the state of the controlled object 500 with respect to the input (disturbance) 801 and the output (state amount) 803. From these, a fluctuation rate (degree of influence) is calculated. The controlled object influence DB 713 classifies and accumulates the degree of influence according to the controlled object state determined by the controlled object state grasping device 601, which will be described in detail later. Since the physical meaning of the signal differs depending on the type of input or output and it is difficult to make a general comparison, an allowable range is set according to the type of each signal, within which fluctuations are not a problem, and the rate at which the output (state quantity) has changed relative to the allowable range when the input (operation quantity, disturbance) fluctuates within the allowable range is regarded as the degree of influence. In the control system design device 702, a control object characteristic DB 711, a control system template DB 712, and a control object influence DB 713 are used to carry out the design work of a new control system.

[0032] FIG. 8 is a diagram showing an example of the controlled object characteristic DB 711 and the control system template DB 712. As shown in FIG. The controlled object characteristic DB 711 is a database in which the characteristics of the controlled object 500 are registered. The characteristics of the controlled object 500 can be determined from electrical and mechanical characteristics, so the characteristics are measured in advance and registered in the controlled object characteristic DB 711. Here, an actuated end actuator transfer function 812, a state quantity detector transfer function 813, and a disturbance transfer transfer function 814 are registered as the characteristics of the controlled object 500. The control system template DB712 is a database in which templates of control systems are registered. A template of a control system to be automatically designed is registered in advance in the control system template DB712. In this example, FF control and FB control are registered as control system templates. The control system template DB712 also registers a control system stability margin, which is used during actual design.

[0033] The controlled object state grasping device 601 monitors the state of the controlled object 500, and judges the quality of the product produced by the controlled object 500 by analyzing the performance data. Here, when the controlled object state is state B (see FIG. 7) where the output (state quantity) 803(a) fluctuates greatly and the product quality is deteriorating, a case where a new control system is created as a countermeasure will be described below.

[0034] FIG. 9 is a diagram showing a procedure for automatically designing a control system. As shown in FIG. 9, the automatic design of a control system involves analysis of the relationship between the input and output of a control object 500, selection of the input and output to the control system, and selection of a control system, and finally setting of the control system gain. In the input / output relationship analysis, it is understood from the controlled object influence DB 713 that when the controlled object state is state B, the degree of influence from the input (operating amount) 802(a) to the output (state amount) 803(a) is large, and the degree of influence from the input (disturbance) 801(b) to the output (state amount) 803(a) is large. Therefore, in this case, FF control or FB control is selected as the control system. As for the input and output to the control system, for FF control, it is effective to use input (disturbance) 804(b) as the input and input (operating variable) 802(a) as the output. For FB control, it can be determined that the control effect is large if output (state variable) 803(a) is used as the input and input (operating variable) 802(a) is used as the output.

[0035] The method shown in FIG. 9 can also be said to create a control system in the following steps. First, a controlled object state grasping device 601, which is an example of an acquiring means, acquires a predetermined state quantity of the controlled object 500. This state quantity corresponds to an input (disturbance) 801, an input (operation quantity) 802, and an output (state quantity) 803. In this case, it is possible to extract a more suitable one as the state quantity. Next, a controlled object state grasping device 601, which is an example of a detection means, detects an abnormality in the state quantity of the controlled object 500 from the operation performance of the controlled object 500. When the product quality deteriorates, an abnormality in the state quantity occurs. Furthermore, a control object analysis device 701, which is an example of a determination means, estimates the correlation between state quantities of the control object 500, and determines the input state quantity, output state quantity, and type of control system required to control the control object 500. Estimating the correlation corresponds to the above-mentioned input / output relationship analysis. The input state quantity corresponds to the input (disturbance) 801 and the input (operation quantity) 802. The output state quantity corresponds to the output (state quantity) 803. In the above-mentioned example, the type of control system corresponds to FF control and FB control. At this time, the control object analysis device 701 obtains the input state quantity and output state quantity with a relatively large correlation, and the relationship between the input state quantity and the output state quantity, and determines the input state quantity, output state quantity, and type of control system required to control the control object 500 from the obtained relationship. This makes it possible to determine the input state quantity, output state quantity, and type of control system with a large control effect. This correlation is obtained based on the degree of influence of past operation results on the input state quantity, as explained in FIG. 7. This makes it possible to judge the control effect based on the past operation results. Then, a control system design device 702, which is an example of a setting means, sets a transfer function, which is a time response of the controlled object 500, and control parameters of the control system. In this case, it is possible to improve the value of the product manufactured by the controlled object 500 and improve manufacturing efficiency.

[0036] 10 and 11 are diagrams showing an example of a control system created by the procedure shown in FIG. Here, the transfer function of the actuator G A (a), T DA (a), T A (a) shows the operation end transfer function parameters (see FIG. 8) of the input (a), and the same is true for the state quantity detection device transfer function and the disturbance transfer transfer function. The control plant transfer function GG is the transfer function G from the input (operational variable) to the output (state variable). GA (a,a) and the transfer function G from the input (disturbance) to the output (state quantity) GD The result is (b,a). By the above procedure, a new control system can be created, and transfer functions for FB control 805 as shown in Fig. 10 and FF control 804 as shown in Fig. 11 can be created. Since each control parameter of the transfer function is determined numerically, each control parameter of FF control 804 and FB control 805 can be determined so as to be the control system stability margin set in the control system template DB 712. The control parameters may be determined by simulating the time response while changing the control gain to determine the optimal values, or the control parameters may be automatically set by a computer using a method such as creating a Bode plot or a Nyquist plot to set the control parameters.

[0037] In this manner, it is possible to automatically design a control system that is considered to be effective in suppressing abnormalities in product accuracy, depending on the state of the control target 500. Here, one-input one-output FF control 804 and FB control 805 are used as the control system template, but other control systems such as optimal control may be set. In that case, the control parameters to be set in the control system design and the method of setting the control system stability margin will differ, but this can be handled by changing the contents of the control system template DB 712 and the method of setting the control parameters. In the control system registration device 703, the newly designed new control system is set as a registered control system 615, and is set as an effective control system when the control target 500 in the registered control system DB is in state B. This makes it possible to carry out adjustment and confirmation work for the new control system as one of the registered control systems 615 described below.

[0038] <Explanation of the method for controlling the control target 500> Next, a method of controlling the control target 500 using a control system that is already prepared or a control system created by the above-mentioned method will be described. FIG. 12 is a conceptual diagram showing in more detail the overall configuration of the control system S shown in FIG. As shown in the figure, the control system S includes a controlled plant 510 which is an example of a predetermined controlled object 500, a control device 511 which selects and executes a control system 501, an actuating device 512 which operates the controlled plant 510, and a state quantity detection device 513 which detects the state quantity of the controlled plant 510. In this case, a state quantity detection device 513 detects a state quantity of the controlled plant 510. Then, a control system 501 of the control device 511 performs control calculation and outputs a control command to an actuated end actuator 512. Furthermore, the actuated end actuator 512 sends a control command to the control actuated end of the controlled plant 510 to operate the controlled plant 510. In this control system S, there are n types of control systems 501, control system-1 to control system-n, and the control device 511 selects and executes one of the control systems 501 depending on the detected state of the controlled plant 510.

[0039] First, the operation of the conventional control system S will be described below. Generally, a control device 511 made by one manufacturer is used for a certain controlled plant 510. Furthermore, the state quantities and control commands of the controlled plant 510 required by the control system 501 differ depending on the control objective. Therefore, although control devices 511 made by different manufacturers may be used for a plurality of control objectives, a control device 511 made by one manufacturer is usually used for a single control objective. Furthermore, the control device 511 is delivered with the control system 501 incorporated therein when the controlled plant 510 is delivered, and thereafter, the manufacturer of the control device 511 will update the control system 501, etc.

[0040] As described above, the control system 501 is constantly being developed, and new control systems 501 are being created. For example, when a new control system 501-N is created, it is expected that the use of the new control system 501-N will improve the product value and manufacturing efficiency. However, it will be necessary to change the control system 501 housed in the control device 511 to the new control system 501-N. In that case, it will be necessary to verify the effectiveness of the control system 501-N, adjust the optimal control gain, and verify the range of state quantities of the control target plant 510 that can be used.

[0041] The controlled plant 510 is usually operated for manufacturing products, and in order to verify the new control system 501-N, it is necessary to avoid the influence of the verification on the product as much as possible. Therefore, it is necessary to find a period during which the new control system 501-N can be verified based on the operating state of the controlled plant 510, the product manufacturing plan, etc., and during that period, replace the conventional control system 501 with the new control system 501-N and verify its effect, control gain, usable range, etc. Currently, the verification of the new control system 501-N is performed by skilled operation engineers, control engineers, and other engineers. Since the controlled plant 510 often operates 24 hours a day, 365 days a year, the verification of the new control system 501-N may be performed at night or on holidays, which places a heavy burden on the engineers.

[0042] There are usually a plurality of manufacturers capable of manufacturing a control device 511 for a certain controlled plant 510. However, there is a problem that it is difficult to replace a new control system 501-N developed by a manufacturer different from the manufacturer of the currently used control device 511 with this control device 511, since it is necessary to understand the internal structure, etc., of the control device 511. Therefore, in the past, even if a control system 501-N was developed as the latest control system 501 for the controlled plant 510, it was difficult to introduce this.

[0043] Therefore, in the control device 511 of this embodiment, this problem is solved by using the method described below. That is, in the control device 511 of this embodiment, it is possible to easily introduce other control systems 501, including new control systems 501-N developed by other manufacturers and control systems created by the method shown in Fig. 9. Also, in the control device 511 of this embodiment, it is possible to introduce and adjust other control systems 501, including new control systems 501-N, while reducing the burden on engineers and the like.

[0044] Returning to Fig. 5, the control system S further includes a control device 511. The control device 511 includes a control object state grasping device 601, a control system switching device 602, a control system adjustment device 603, a control system selection DB (database) 604, a registered control system DB 605, an abnormality determination device 606, a production planning device 609, and an adjustment result DB 621. Fig. 5 also illustrates a control object 500. The controlled object 500 and the control device 511 are the same as those described above. That is, the controlled object 500 is a general controlled plant 510. The control device 511 is a device that selects and executes the control system 501. The controlled object state grasping device 601 acquires the state quantity of the controlled object 500 and grasps the state of the controlled object 500 . The control system switching device 602 switches the control system 501. Although details will be described later, here, a general-purpose control system 614 and registered control systems 615B to 615Z are prepared as the control system 501, and the control system switching device 602 selects and switches the control system 501 from among them. The control system adjustment device 603 adjusts the control system 501. That is, it adjusts the control gain, etc. In this case, the control system adjustment device 603 mainly adjusts the registered control systems 615B to 615Z. The control system selection DB 604 registers information for defining the state of the control target 500 . The registration control system DB 605 registers input data and output data required by each of the registration control systems 615B to 615Z. The abnormality determination device 606 determines whether or not an abnormality has occurred in the controlled object 500 or in a product manufactured by the controlled object 500 . The production planning device 609 stores a production schedule for the products manufactured by the controlled object 500 . The adjustment result DB 621 stores the results of the adjustment of the control system 501 performed by the control system adjustment device 603 .

[0045] The control device 511 also includes an input data connection device 611, a control output switching device 612, an output data connection device 613, a general-purpose control system 614, and registered control systems 615B to 615Z. The registered control systems 615B to 615Z include the control systems created by the method shown in FIG.

[0046] The input data connection device 611 provides input data to the control system 501. In this case, the input data is provided to one or more control systems 501 selected from the general-purpose control system 614 and the registered control systems 615B to 615Z. The control output switching device 612 switches the control system 501 to be applied to the control target 500. At this time, the control output switching device 612 outputs a control command to the control target 500. The output data connection device 613 receives output data from the control system 501 . The general-purpose control system 614 is the normally used control system 501. The general-purpose control system 614 is a proven control system (proportional-integral control, etc.) for the control target 500, and the control device 511 normally controls the control target 500 using the general-purpose control system 614. The registered control system 615 is a control system registered in advance for the purpose of improving the control function of the general-purpose control system 614. A plurality of control systems 501 can be registered in the registered control system 615 in advance. Here, in order to identify each registered control system 615, it is illustrated as a registered control system 615x (an appropriate symbol is assigned to x. Here, B to Z are assigned). The input data connection device 611, the output data connection device 613, and the registered control system 615 may be referred to as a registered control system execution device 620 as a device that executes the registered control system 615. Then, when the control system switching device 602 decides to use one of the registered control systems 615B to 615Z instead of the general-purpose control system 614, the general-purpose control system 614 stops control, and the registered control system execution device 620 executes control of the control target 500 with the selected registered control system 615.

[0047] <Detailed explanation of the data used in the control system S> 12, the state quantity detection device 513 detects the state quantity of the controlled plant 510. Then, the control system 501 of the control device 511 performs control calculations and outputs a control command to the operated end actuator 512. Furthermore, the operated end actuator 512 operates the controlled plant 510. In this case, the input data is the output of the state quantity detection device 513, and the output data is the input of the operated end actuator 512, and the controlled plant 510 is controlled.

[0048] These input data and output data are determined according to the purpose of the control system 501. The input data is, for example, data output from the state quantity detection device 513. Moreover, the output data is data input to the operation end actuator 512. Therefore, by connecting the necessary input data and output data to the control device 511, it becomes possible to replace the control system 501.

[0049] Therefore, in this embodiment, the input data and output data required by each of the registration control systems 615B to 615Z are registered in advance in a database, that is, a registration control system DB 605. Then, the registration control system DB 605 and the input data connection device 611 are connected. As a result, the input data to be output to the input data connection device 611 is set. Also, the registration control DB 605 is connected to the output data connection device 613. As a result, the output data output from the output data connection device 613 is set.

[0050] Furthermore, since there is information required for control gain calculation, control timing determination, and the like in controlling the controlled object 500, the registered control system DB 605 also registers this information. The information is, for example, the mechanical characteristics of the controlled object 500, the specifications of the detector and control operation terminal, the interlock conditions, the manufactured product specifications, and the like. Hereinafter, this information may be referred to as "plant information". This plant information is also used as input data. In addition, in order to check the operation of the control system 501, the internal state quantity of the control system 501 is required in addition to the output to the control operation terminal. Therefore, the registered control system DB 605 is set up so that the internal state quantity of the control system 501 can be registered in addition to the control output (control command) to the control operation terminal. The data may also be made available to the control system adjustment device 603 as data required for analysis of the control system 501.

[0051] In controlling the controlled object 500, steady-state deviation removal characteristics (removing steady-state errors in the control model, dealing with cases where disturbances change in a step or ramp manner), frequency characteristics (improving the frequency characteristics of the controlled object, detector, and control operation terminal), disturbance removal characteristics (cancelling disturbances to the control system), etc. are necessary for performance evaluation. Since it is difficult to endow the control system 501 with characteristics that improve all of these, the control system 501 is usually developed to improve one or more characteristics.

[0052] The occurrence status of disturbances to the controlled object 500, the fluctuation factors of state quantities, frequency characteristics, etc. can be investigated and generally known in many cases. Therefore, the required control characteristics are defined from the state quantities and production schedule of the controlled object 500, so that they can be grasped and recognized by the controlled object state grasping device 601. The state quantities of the controlled object 500 and the production schedule from the production planning device 609 are input to the controlled object state grasping device 601. The production planning device 609 is a device that manages the production status of products manufactured by the controlled object 500, and outputs to the controlled object state grasping device 601 what products are to be produced, in what order, and at what time.

[0053] When a new control system 501 is developed, it is necessary to check its performance and adjust the control gain, etc. In this case, depending on the control system 501, there is a possibility that it may oscillate or diverge. Therefore, tests are first performed using products that do not have a problem even if the product quality deteriorates slightly, or in some cases, test products that do not care about the product quality. Then, once it is confirmed that there are no problems with the control operation, it is necessary to gradually perform tests using the product materials.

[0054] Therefore, input data, output data and control characteristics for the registered control system 615 are registered in advance in the registered control system 615. Then, based on that information, the input data connection device 611 provides appropriate state quantity data of the controlled object 500 to the registered control system 615. Furthermore, in order to output an appropriate control output to the controlled object 500, the output data connection device 613 receives appropriate output data.

[0055] In addition, as control characteristics, the registered control system 615 also registers design specifications (information on the characteristics of the control system such as frequency characteristics and target state quantity fluctuation factors) that indicate the characteristics of the control system 501, and adjustment specifications (initial settings and adjustment ranges of control parameters such as control gain and phase delay compensation) of the control system 501.

[0056] Information about these registered control systems 615 is also registered in the registered control system DB 605 . FIG. 13 is a diagram showing the contents of data registered in the registered control system DB 605. As shown in FIG. In the registered control system DB 605, data as shown in the figure is registered for each of the registered control systems 615B to 615Z. Here, an explanation will be given by taking as an example the case of one of the registered control systems 615. It should be noted that this content can also be said to be the data structure of the registered control system DB 605. In the registered control system DB 605, for example, detector data indicating which detector data is to be used is registered as input data. Here, the detectors are detector 1, detector 2, ..., and as detector data detected by these detectors, 1 is set for detector data necessary for the registered control system 615, and 0 is set for detector data not necessary. In addition, in the registered control system DB 605, for example, plant information is registered as input data. The plant information is information 1, information 2, ..., and 1 is set for plant information necessary for the registered control system 615, and 0 is set for plant information not necessary.

[0057] In the registered control system DB 605, for example, operation end data indicating which operation end is to be used is registered as output data. Here, the operation ends include operation end 1, operation end 2, ..., and 1 is set for the operation end used by the registered control system 615, and 0 is set for the operation end not used. In addition, in the registered control system DB 605, for example, internal information data indicating which internal information of the internal information of the control system 501 is to be used is registered as output data. Here, the internal information includes state amount 1, state amount 2, ..., and 1 is set for the internal information used by the registered control system 615, and 0 is set for the internal information not used.

[0058] It can be said that the registered control system DB 605 registers the relationship between the input data (in this case, detector 1, detector 2, ..., information 1, information 2, ...) input to each registered control system 615 and the output data including information on the output destination (in this case, operation end 1, operation end 2, ..., state quantity 1, state quantity 2, ...) to which the registered control system 615 outputs a control command to the control target 500. A plurality of these relationships are prepared in advance for each registered control system 615. As shown in the figure, the registered control system DB 605 has a plurality of input data and a plurality of output data, and the above relationship associates at least one of the plurality of input data with at least one of the plurality of output data. Then, the control output switching device 612 selects the registered control system 615 that controls the control target 500 based on the associated combination of input data and output data.

[0059] Furthermore, state quantity fluctuation factors, frequency characteristics, control system configuration, etc. are registered in the registered control system DB 605 as design specifications indicating the characteristics of the control system 501. The state quantity fluctuation factors define what state quantity fluctuations are to be controlled. The frequency characteristics register a control method (FF (feedforward) control, PID control, the presence or absence of an offset removal function, etc.) that can obtain a state quantity attenuation effect for a frequency. In addition, the registered control system DB 605 registers adjustment specifications for adjusting the control system 501. Here, adjustable ranges of control parameters such as control gain and delay time settings are registered according to adjustment purposes such as reducing the amplitude of state quantities and removing offsets. Moreover, the adjustment state is registered in the registered control system DB 605 as a result of performing adjustment of the control system 501. The adjustment state is, for example, a stage of operation confirmed, rough adjustment completed, or fine adjustment completed.

[0060] On the other hand, information for defining the state of the control target 500 is registered in the control system selection DB 604. In this way, according to the state of the control target 500 grasped by the control target state grasping device 601, an appropriate control system 501 can be selected and used from the registered control systems 615.

[0061] FIG. 14 is a diagram showing the contents of data registered in the control system selection DB 604. As shown in FIG. Here, product information, product characteristics, and equipment status are registered as the control system selection DB 604. It can also be said that this content is the data structure of the control system selection DB 604. The product information is information that defines the type of product. Here, as the product information, product conditions (product conditions A to C) and allowable accuracy are registered for each of the three types of material: test material, normal material, and strict material. When the registered control system 615 is applied to adjust the control system 501, the product accuracy may be deteriorated. For this reason, it is necessary to define the type of product to be produced. As the type of product to be produced, for example, a test material that may deteriorate in product accuracy and be scrapped, a normal material with a wide tolerance range for product accuracy, or a strict material with a narrow tolerance range is registered. In addition to the product accuracy, it is also necessary to define in advance the allowable accuracy so that the product quality does not damage the control target 500.

[0062] Furthermore, the product characteristics are information relating to state variation factors as factors affecting the state quantity of the controlled object 500, and the magnitude of the variation in the state quantity of the controlled object 500 in response to these. The impact of disturbance factors on the state quantity of the controlled object 500 differs depending on the product. Therefore, this information is registered as product characteristics as factors affecting the state quantity of the controlled object 500. In the example given here, conditions are set that result in large variation due to factor 1. As conditions, for example, in addition to product conditions produced by the controlled equipment, state quantity conditions related to the production situation such as speed are set. Similarly, conditions such as when the amplitude of the state quantity of the controlled object is large or when the offset error is large are registered.

[0063] The equipment status is the operating status of the controlled object. Here, the equipment status is registered as having three states: Under repair, Stopped, and In production operation.

[0064] <Detailed explanation of the operation of control system S> FIG. 15 is a diagram showing an operation flow of the control system S when the control target 500 is controlled using the general-purpose control system 614 and the registered control systems 615B to 615Z. The registered control system executing device 620 connects the input data connecting device 611 and the output data connecting device 613 to keep the registered multiple control systems 615B-615Z in an executable state. The input data and output data of each of the registered control systems 615B-615Z are registered in advance in the registered control system DB 620. The connecting device 611 connects to each of the registered control systems 615B-615Z so that the detected value of the state quantity of the control target 500 can be input as input data. Furthermore, the output data connecting device 613 connects to each of the registered control systems 615B-615Z so that the output data to be output to the control operation terminal of the control target 500 can be output.

[0065] The controlled object state grasping device 601 acquires information about the product manufactured by the controlled object 500 from the production planning device 609. The "information about the product" is, for example, a production schedule for the product manufactured by the controlled object 500. The controlled object state grasping device 601 then creates product conditions and state quantity conditions using this product information and the state quantities of the controlled object 500 (step S101). The "product conditions" are conditions such as the material of the product, the allowable range of product accuracy, and the shipping destination. The "state quantity conditions" are conditions such as the type of state quantity and the allowable range of the state quantity. The controlled object state grasping device 601 functions as an acquiring means for acquiring the predetermined state quantities of the controlled object 500.

[0066] Next, the control system switching device 602 obtains the product information and product characteristics described in FIG. 14 using the information of the control system selection DB 604 from the product conditions and state quantity conditions created by the controlled object state grasping device 601. Furthermore, the control system switching device 602 selects a registered control system 615 that matches the product information and product characteristics from among the registered control systems 615B to 615Z using the information registered in the registered control system DB 605 (step S102). Specifically, the control system switching device 602 selects, for example, a registered control system 615 that matches the product conditions of the product information (product conditions A to C in the example of FIG. 14). Furthermore, the control system switching device 602 selects, for example, a registered control system 615 that matches the allowable accuracy of the product information. Furthermore, the control system switching device 602 selects, for example, a registered control system 615 that can suppress product characteristics that are likely to occur depending on the type of product. That is, if an oscillation is likely to occur depending on the type of product, the registered control system 615 that can suppress it is selected. Furthermore, if offsets are likely to occur depending on the type of product, a registered control system 615 capable of suppressing this is selected. Note that the registered control system 615 may be selected using a combination of multiple conditions in the product information and product characteristics, priorities, and the like. The control system switching device 602 functions as a selection means for selecting the state quantity of the control object 500 acquired by the control object state grasping device 601 and the control system 501 for controlling the control object 500 . Then, the control system switching device 602 instructs the output data connection device 613 to output, to the control output switching device 612, the output from the registered control system 615 that has been determined to be applicable.

[0067] Next, the output data connection device 613 outputs the output of the selected registered control system 615 to the control output switching device 612 (step S103).

[0068] Furthermore, when the registered control systems 615B to 615Z are checked for operation and adjusted, malfunction may occur, and the state quantities including the state quantities controlled by the controlled object 500 may become abnormal. For example, this may occur when the state quantities of the controlled object 500 deteriorate below the allowable accuracy set as product information in the control system selection DB 604. In this case, the abnormality determination device 606 detects the abnormality and switches the control output for the controlled object 500 from the output of the registered control system execution device 620 to the output of the general-purpose control system 614. That is, the output of the selected registered control system 615 is switched to the output of the general-purpose control system 614. This makes it possible to check the operation and adjust the registered control system 615 while avoiding abnormalities in the controlled object 500. Therefore, the control target state grasping device 601 judges whether or not the abnormality judging device 606 detects an abnormality (step S104). As a result, if the abnormality judgment device 606 detects no abnormality and determines that the controlled object state grasping device 601 is normal, the control output switching device 612 outputs the output of the selected registered control system 615 to the controlled object 500 (step S105).

[0069] The control system adjustment device 603 judges whether the adjustment of the selected registered control system 615 has been completed (step S106). As a result, if the control system adjustment device 603 determines that the adjustment of the registered control system 615 has not yet been completed (is incomplete), the control system adjustment device 603 performs an adjustment operation on the registered control system 615 (step S107). The adjustment operation is performed for the selected registered control system 615 based on the adjustment specifications registered in the registered control system DB 605. For example, when the amplitude of the state quantity of the controlled object 500 is large, the control system adjustment device 603 adjusts the registered control parameter 1 and control parameter 2. Also, for example, when it takes time to correct the offset error, the control system adjustment device 603 adjusts the control parameter 3 and control parameter 4.

[0070] Information on the adjustment process (such as the set values ​​of the control parameters and the actual values ​​of the state quantities of the controlled object 500) is collected by the control system adjustment device 603 and stored in an adjustment result DB 621. The creator of the registered control system 615 can later examine the adjustment results stored in the adjustment result DB 621 to further improve the performance of the registered control system 615.

[0071] On the other hand, in step S104, if the abnormality determination device 606 detects an abnormality and the controlled object state grasping device 601 judges that there is an abnormality, the registered control system execution device 620 stops the control of the selected registered control system 615 and performs control of the controlled object 500 by the general-purpose control system 614 (step S108).

[0072] The registered control system 615 output to the control target 500 is not limited to one, and multiple registered control systems 615 can be used in combination. For example, separate registered control systems 615 can be applied to FF control (feedforward control) and offset removal control. It is also possible to adjust each registered control system 615 applied to the separate controls. In this case, the control method for controlling the control target 500 consists of multiple control methods, and it can be said that the control output switching device 612 selects a control system selected from the general-purpose control system 614 and the registered control system 615 for each of the multiple control methods. When the product produced by the control target 500 is changed and the product conditions and state quantity conditions are changed, the control system 501 is switched by an instruction from the control system switching device 602. At this time, the control system 501 is selected from the general-purpose control system 614 and the registered control systems 615B to 615Z.

[0073] The control system adjustment device 603 registers the adjustment state of the registered control system DB 605 according to the state of the operation check and adjustment work of the registered control system 615. The adjustment state can be represented by a flag meaning, for example, "operation confirmed", "coarsely adjusted", or "finely adjusted". "Operation confirmed" is turned ON (1) when a control effect is obtained as a result of outputting the output of the registered control system 615 to the control target 500. "Coarsely adjusted" is turned ON when a certain degree of control effect is confirmed. "Finely adjusted" is turned ON when the control effect is greater than that of the general-purpose control system 614. One of these flags is turned ON, and the others are turned OFF (0).

[0074] The control system adjustment device 603 refers to the adjustment state registered in the registered control system DB 605. Then, when the finely adjusted flag is ON, the control system adjustment device 603 determines that the adjustment is completed, stops the control system adjustment work by the control system adjustment device 603, and uses it as a normal control system 501. The control system adjustment device 603 monitors the operating state of the registered control system 615, and if the control effect decreases, it resets the adjustment state flag. For example, if the damping effect deteriorates as a state quantity of the controlled object 500 and the finely adjusted flag is set to OFF, adjustment work of the registered control system 615 is performed again. On the other hand, if the finely adjusted flag is ON, the control system adjustment device 603 continues to use the registered control system 615 depending on the state of the controlled object 500. This makes it possible to select the optimal control system 501 depending on the state of the controlled object 500.

[0075] <Detailed Description of the Registration Control System Execution Device 620> Fig. 16 is a diagram showing an outline of the processing performed by the registered control system executing device 620. Fig. 17 is a diagram showing input data and output data registered in the registered control system DB 605 for each registered control system 615. 17, input data and output data to be used for the general-purpose control system 614 and each of the registered control systems 615B to 615Z are registered in the registered control system DB 605. Here, it is assumed that detectors 550-1 to 550-n are installed in the controlled object 500 as detectors 1 to n for detecting state quantities. It is also assumed that 551-1 to 551-m are installed as operation terminals 1 to m for operating the controlled object 500. It is also assumed that information 553-1 to 553-k is provided from the controlled object 500 as information 1 to k other than the detection values ​​of the detectors 550-1 to 550-n. The information 1 to k is information on various set values, etc.

[0076] Here, as an example, a case where a state quantity 1 detected by a detector 550-1 is used is considered. In this case, a target value 552-1 is set in advance as the state quantity 1, which is a target value for control. A control deviation is calculated as essential information for the general-purpose control system 614 and the registered control systems 615B to 615Z. The control deviation is the deviation between the detection value by the detector 550-1 and the target value 552-1. The control deviation is essential information for the general-purpose control system 614 and the registered control systems 615B to 615Z, and is input to each of these control systems unconditionally. Since the use or non-use of other information is optional for each of these control systems, the use or non-use is defined by a flag (0 or 1) in the input data column of the registered control system DB 605. That is, if not used, it is defined as 0 in the input data column, and if used, it is defined as 1. In the example of Fig. 17, registration control system 615B (registration control system B) uses only the output of detector 550-n as input data, so in the input data column, the input data column for detector n is set to 1. On the other hand, the other input data columns are set to 0. Also, registration control system 615C (registration control system C) uses only the output of detectors 550-1 and 550-2 as input data. Therefore, in the input data column, the input data columns for detectors 1 and 2 are set to 1, but the other input data columns are set to 0. Furthermore, in the registration control system 615Z (registration control system Z), only the information 553-1 is used as input data. Therefore, in the input data column, the input data column for the information 1 is set to 1, but the other input data columns are set to 0.

[0077] In this way, in the registered control system DB 605, when the general-purpose control system 614 and each of the registered control systems 615B to 615Z do not use the above information as input data, 0 is set. On the other hand, when the above information is used as input data, 1 is set.

[0078] Based on the information in the registration control system DB 605, the input data connection device 611 inputs input data selected from the detection values ​​and information 553-1 to 553-k of the detectors 550-1 to 550-n to the corresponding registration control system 615. Generally, the processing performed by the control device 511 is performed by a computer and is software processing, so it is possible to automatically create software that performs this processing.

[0079] The controlled object 500 has a plurality of control operation terminals 551 for changing the state quantity. In FIG. 16, m operation terminals 551-1 to 551-m are illustrated as the plurality of operation terminals 551. The relationship between the control operation terminal 551 and the state quantity is generally complicated, and the effect of changing the control operation terminal 551 extends to a plurality of state quantities. Therefore, when controlling the state quantity of the controlled object 500, there are cases where the controlled object 500 operates a plurality of control operation terminals 551, or where a control output is output to different operation terminals 551 depending on the control system. Therefore, the control operation terminal 551 is registered as output data in the registered control system DB 605. The registered control system 615 defines the control operation terminal 551 to which the control output is to be output in accordance with the control characteristics.

[0080] It is necessary to switch between the outputs from the general-purpose control system 614 and the registered control system 615 and output them as the control output to the control operation terminal 551. Therefore, it is necessary to create the difference between the control outputs of these control systems (the difference from the control output one sampling before), add up the differences in the outputs of the control systems, and integrate them before outputting them to the operation terminal 551. To achieve this, the output data connection device 613 performs the following processing. The output of each control system is subtracted from the previous output value, a gain is applied to it, and the output to each operation terminal 551 is added. The control operation terminal 551 to which each registered control system 615 outputs is determined by the output data of the registered control system DB 605 and the output presence / absence flag (0 or 1). Then, after subtracting the output of each control system, the output gain G XM Here, the subscript X indicates which control system it is (0 indicates general-purpose control system 614, and B to Z indicate registered control systems 615B to 615Z), and the subscript M indicates which of control operation terminals 551-1 to 551-m it is (for example, when M is 1, it indicates control operation terminal 551-1).

[0081] The control output switching device 612 switches between the control output of the general-purpose control system 614 and the control output from the output data connection device 613. Considering the case where the general-purpose control system 614 outputs the control output to the control operation terminal 551-1, as shown in FIG. 16, the difference of the output from the general-purpose control system 614 is taken and a gain G 01 and the output from the output data connection device 613 to the control operation terminal 551-1. R1 7, the signal from the output data connector 613 to the control terminal 551-2 is connected to the gain G R2 The result multiplied by and integrated is used as the control output to the operation terminal 551-2. As a result, the gain G 01 and gain G R1 , G R2 By setting the above, switching between the general-purpose control system 614 and the registered control system 615 can be realized.

[0082] When using the general-purpose control system 614, the gain G 01 and gain G R1 , G R2 The settings are as follows: G 01 =1.0, Gain G R1 =0.0, G R2 =0.0

[0083] Furthermore, the gain G when using the registration control system 615 01 and gain G R1 , G R2 The settings are as follows: G 01 =0.0, G R1 =1.0, G R2 =1.0

[0084] In addition, when using the registration control systems 615B to 615Z, when switching to one of them, the gain G B1、 G C1、 G C2、 G Z2 The settings are as follows: Here, an example will be described in which switching is performed between registration control system 615B, registration control system 615C, and registration control system 615Z.

[0085] When using the registration control system 615B, G B1 =1.0, G C1 =0.0, G C2 =0.0, G Z2 =0.0

[0086] When using the registration control system 615C, G B1 =0.0, G C1 =1.0, G C2 =1.0, G Z2 =0.0

[0087] When using the registration control system 615Z, G B1 =0.0, G C1 =0.0, G C2 =0.0, G Z2 =1.0

[0088] The output data connection device 613 and the control output switching device 612 are also generally processed by software, so that the above software can be created automatically. When the abnormality determination device 606 determines that an abnormality has occurred in the controlled object (such as when a state quantity exceeds a predetermined value), by changing the control gain in accordance with the case where the general-purpose control system 614 is used, it becomes possible to switch from the registered control system 615 to control by the general-purpose control system 614, thereby avoiding the abnormality.

[0089] [Second embodiment] Next, a second embodiment of the control system S to which the present embodiment is applied will be described. In the second embodiment, the control system S controls a single stand rolling mill as a controlled object 500. In this case, a product manufactured by the single stand rolling mill is a rolled material such as a steel plate.

[0090] In the single stand rolling mill, which is one of the plants 510 to be controlled, control systems each having their own characteristics may be selected and combined as appropriate. In this case, it is necessary to implement the control so that the thickness accuracy of the final product obtained by rolling is the best possible according to the rolling condition of the single stand rolling mill (condition of the rolling mill, condition of the material to be rolled, etc.). If this is not implemented, the specified thickness accuracy may not be obtained, and the product may not be what the customer requires. For this reason, even in plate thickness control applied to maintain plate thickness accuracy, a plurality of control systems are applied depending on the rolling state, and the most suitable control system is selected and used as appropriate.

[0091] In single-stand rolling mills, the thickness accuracy of the material being rolled, such as the thin plate that will become the product, is an important control target that is directly linked to the product quality, and various methods have been developed and applied. When applying a newly developed control method, it is necessary to switch from the existing control and change the gain, etc., depending on the rolling state, and these conditions must be determined. When determining the conditions, it is sometimes necessary to increase the thickness variation, which is important for product quality, and for this reason, it is necessary to use test materials or rolled materials with looser thickness accuracy requirements.

[0092] FIG. 18 is a schematic diagram showing a control system S in the second embodiment. As shown in the figure, the control system S includes a rolling mill A, an entry-side tension reel 2 (hereinafter also referred to as the "entry-side TR2"), and an exit-side tension reel 3 (hereinafter also referred to as the "exit-side TR3"). The rolling mill A, the entry-side TR2, and the exit-side TR3 are controlled objects 500 of the control system S. In this embodiment, the "entrance side" means the side from which the material m to be rolled is sent toward the rolling mill A (the upstream side of the rolling mill A), and the "exit side" means the side from which the material m to be rolled is sent out from the rolling mill A (the downstream side of the rolling mill A). Also, the "deviation" means the difference between a set value or a predicted value and an actual measured value (actual value).

[0093] The illustrated control system S includes a control device 411, a controlled object state grasping device 401, a control system switching device 402, a control system adjustment device 403, a control system selection DB 404, a registered control system DB 405, an abnormality determination device 406, and a production planning device 409. These correspond to the control device 511, the controlled object state grasping device 601, the control system switching device 602, the control system adjustment device 603, the control system selection DB 604, the registered control system DB 605, the abnormality determination device 606, and the production planning device 609 in Fig. 5, respectively, and have similar functions. Note that descriptions of functional units corresponding to the controlled object analysis device 701, the control system design device 702, the control system registration device 703, the controlled object characteristic DB 711, the control system template DB 712, and the controlled object influence DB 713 in Fig. 5 are omitted. The illustrated control system S uses three control systems: a general-purpose control system, a reduction thickness control 414, and a registration control system, a speed ratio thickness control 415B, and a mill speed thickness control 415C.

[0094] The rolling mill A is an example of a single stand rolling mill. The rolling mill A has a roll pair consisting of an upper work roll R1 (hereinafter also simply referred to as "roll R1") and a lower work roll R2 (hereinafter also simply referred to as "roll R2"). The rolling mill A receives signals from a roll gap control unit 21 and a mill speed control unit 31, which will be described in detail later, in the rolling control device 11. The mill speed is set by a mill speed setting unit 81. Then, in accordance with the signals, the rolling mill A adjusts the interval (hereinafter also referred to as "roll gap") between the rolls (upper work roll R1 and lower work roll R2) in the roll pair rotating at a predetermined peripheral speed, thereby rolling the material m to be rolled that passes between the roll pair.

[0095] The entry side TR2 and the exit side TR3 each receive signals from an entry side TR control unit 42 and an exit side TR control unit 52, which will be described in detail later, in the rolling control device 11. Then, using electric motors (not shown) provided in the entry side TR2 and the exit side TR3, the entry side TR2 sends out the material m to be rolled to the rolling mill A, and the exit side TR3 winds up the material m rolled by the rolling mill A.

[0096] Here, a rolling phenomenon related to the thickness fluctuation of the rolled material m in a rolling mill A using a pair of rolls will be described. Since the thickness of the rolled material m is important for product quality, thickness control is performed. In this thickness control, the actual value of the thickness of the rolled material m detected by the delivery thickness gauge a2 is used, and the roll gap control unit 21, for example, operates the roll gap between the rolls R1 and R2 to adjust the thickness of the rolled material m on the delivery side.

[0097] Conventionally, the thickness control of a single stand rolling mill has been performed by changing the roll gap using the thickness deviation detected by the entry thickness gauge a1 and the exit thickness gauge a2 of the rolling mill A, performing FF control (feedforward control) or FB control (feedback control), and outputting the control output to the roll gap control unit 21. However, the method of controlling the exit thickness using the roll gap may not be effective enough depending on the set thickness and rolling speed. Therefore, it is necessary to add a new control method, but in a single stand rolling mill that rolls various materials, it is difficult to confirm and actually apply the new control method appropriately in each case. Therefore, if a new control system is registered, a system can be realized that automatically performs operation confirmation, control system adjustment, and actual application. In this case, it is possible to provide optimal control according to the rolling state while reducing the burden on operation engineers and control engineers.

[0098] When the controlled object 500 is replaced with the rolling mill A, the input (disturbance) 901, the input (operation amount) 902, and the output (state amount) 903 become as shown in FIG. That is, the input (disturbance) 901 is (a) roll gap, (b) entry TR speed, and (c) mill speed. The input (operation variable) 902 is (a) entry plate thickness, (b) roll eccentricity, and (c) bender pressure. The output (state variable) 903 is (a) exit plate thickness, (b) rolling load, (c) entry tension, and (d) exit tension. FIG. 20 is a diagram showing a change in shape of the rolled material m due to a change in vendor. In the rolling mill A, the material m to be rolled, which is a metal plate, is rolled, but waviness (called shape) of the metal plate is also an important quality factor, and the operator manually operates the bender to reduce waviness. The bender is a mechanical device that changes the force applied to both ends of the rolls R1 and R2 of the rolling mill A, bending the rolls R1 and R2 to change the shape. When the operator operates and changes the bender, the force (load) applied from the rolls R1 and R2 to the material m to be rolled changes, which may cause the plate thickness to change. For this reason, in FIG. 19, the bender pressure (shown as bender pressure 920 in FIG. 18) is input as an input (disturbance) 901(c). The thickness fluctuation caused by the change in the bender pressure, which is the input (disturbance) 901(c), changes depending on the material of the material m to be rolled and the operating conditions of the rolling mill A, such as the thickness and width of the material. Therefore, when the change is large, FF control is effective, which changes the roll gap, which is the input (operating end) 902(a), in response to the change in the bender pressure, which is the input (disturbance) 901(c), and suppresses the exit thickness fluctuation, which is the output (state quantity) 903(a). In this case, similarly to the "first embodiment," FF control 905 (see FIG. 18) is designed, with the bender pressure as input (disturbance) 901(c) and the roll gap as input (operating end) 902(a) as output, and is automatically designed and added as the control of rolling mill A.

[0099] <Control method explanation> Here, the processing performed by the control system S described in FIG. 9 can be considered as a control method that acquires predetermined state quantities of the controlled object 500, detects abnormalities in the state quantities of the controlled object 500 based on the operational performance of the controlled object 500, estimates correlations between the state quantities of the controlled object 500, determines input state quantities, output state quantities and the type of control system required to control the controlled object 500, and sets a transfer function which is the time response of the controlled object 500 and control parameters of the control system.

[0100] <Program Description> The processes performed by the control system S in the present embodiment described above are realized by the cooperation of software and hardware resources. That is, a processor such as a CPU provided in the control system S executes a program that realizes each function of the control system S, and realizes each of these functions. The program for implementing the present embodiment can be provided not only by communication means but also by being stored in a recording medium such as a CD-ROM.

[0101] Although the present embodiment has been described above, the technical scope of the present invention is not limited to the scope described in the above embodiment. It is clear from the claims that various modifications and improvements to the above embodiment are also included in the technical scope of the present invention. [Industrial Applicability]

[0102] The present invention relates to a method and device for controlling an industrial plant or a rolling mill A which is one of such plants, and there are no particular problems in practical application. [Explanation of symbols]

[0103] 500...Controlled object, 501...Control system, 511...Control device, 401,601...Controlled object state grasping device, 402,602...Control system switching device, 403,603...Control system adjustment device, 701...Controlled object analysis device, 702...Control system design device, 703...Control system registration device, 711...Controlled object characteristic DB, 712...Control system template DB, 713...Controlled object influence DB, 801,901...Input (disturbance), 802,902...Input (operation amount), 803,903...Output (state amount), 810...Controlled object plant transfer function, 812...Operation end actuator transfer function, 813...State amount detection device transfer function, 814...Disturbance transfer transfer function, S...Control system

Claims

1. An acquisition means for acquiring a predetermined state quantity of a control object; A detection means for detecting an abnormality in the state quantity of the controlled object based on an operational record of the controlled object; a determination means for determining an input state quantity, an output state quantity, and a type of a control system required for controlling the controlled object by estimating a correlation between the state quantities of the controlled object; a setting means for setting a transfer function, which is a time response of the controlled object, and a control parameter of the control system; A control device comprising:

2. 2. The control device according to claim 1, wherein the determination means determines the input state quantity, the output state quantity, and the relationship between the input state quantity and the output state quantity, which have a relatively large correlation, and determines the input state quantity, the output state quantity, and the type of the control system required to control the controlled object based on the determined relationship.

3. The control device according to claim 2 , wherein the correlation is determined based on a degree of influence of past operational results on the input state quantity.

4. The control device according to claim 1 , wherein the input state quantity is a manipulation quantity for the controlled object and a disturbance for the controlled object.

5. The control device according to claim 4 , wherein the transfer functions include an end effector transfer function which is a time response to the manipulated variable, and a disturbance transfer function which is a time response to the disturbance.

6. 6. The control device according to claim 5, wherein the transfer functions further include a state quantity detection device transfer function which is a time response to a state quantity detection device, and a controlled plant transfer function which is a time response to the controlled object.

7. The control device according to claim 6 , wherein the transfer function of the controlled plant is a conversion gain with no time response.

8. 7. The control device according to claim 6, wherein the actuated end actuator transfer function, the state quantity detection device transfer function and the disturbance transfer transfer function are predetermined based on characteristics of the controlled object.

9. The control device according to claim 1 , wherein the types of the control system include feedforward control and feedback control.

10. The control device according to claim 9 , wherein the control parameters include a gain of at least one of the feedforward control and the feedback control.

11. 2. The control device according to claim 1, further comprising a selection means for selecting a control system for controlling the controlled object based on the acquired state quantity and the relationship, the control system having a plurality of relationships prepared in advance as input data to be input to a control system and output data including information on an output destination to which a control command is output from the control system to the controlled object.

12. The control target is a thickness of a material to be rolled by a rolling mill, The control device according to claim 1 , wherein the control system controls the thickness of the material to be rolled.

13. Acquire a predetermined state quantity of a control target; Detecting an abnormality in the state quantity of the controlled object based on an operational record of the controlled object; Estimating a correlation between the state quantities of the control object, and determining an input state quantity, an output state quantity, and a type of a control system required for controlling the control object; Setting a transfer function which is a time response of the controlled object and a control parameter of the control system; Control methods.

14. A predetermined control target; A control device that selects a control system to be applied to the control object; having The control device includes: An acquisition means for acquiring a state quantity of the control target; A detection means for detecting an abnormality in the state quantity of the controlled object based on an operational record of the controlled object; a determination means for determining an input state quantity, an output state quantity, and a type of the control system required for controlling the controlled object by estimating a correlation between the state quantities of the controlled object; a setting means for setting a transfer function, which is a time response of the controlled object, and a control parameter of the control system; A control system comprising:

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