CN102497941A - Control method of processing equipment for extended rolling stock - Google Patents

Abstract

Processing plant for elongated rolling stock (1) with upstream and downstream plant parts (2, 3) which are passed directly sequentially by the rolling stock (1) . The plant parts ( 2 , 3 ) are each designed as a finishing train or as a different plant part than the finishing train. For the section ( 14 ) of the rolling stock ( 1 ) passing through the processing plant, the control device ( 10 ) is correspondingly predetermined with at least one final variable which is derived from the corresponding desired final state (Z *) that the corresponding section ( 14 ) of the rolling stock ( 1 ) should have the end state (Z*) after passing through the downstream plant part ( 3 ). The control device (10) realizes at least one control variable ascertainer (16, 20), which provides at least one The means (6, 15, 18, 21) which are influenced by the state (Z) of at least one sector output a control variable (S, S'). The control variables (S, S′) are output at the instant when the at least one section ( 14 ) is located in the upstream system part ( 2 ). When obtaining the control quantities (S, S'), the control quantity obtainers (16, 20) take into account that at least one section (14) of the rolling stock (1) is obtained under the support of the model The expected state obtained is within the prediction period (PH1 to PH5) of the corresponding control variable finder (16, 20). The forecast period (PH1, PH5) is determined in such a way that the control variable determiner (16, 20) takes into account at least one (1) Predicted state of at least one section (14) of the rolling stock (1) in the downstream plant part (3) for at least one section (14) of the rolling stock (1).

Description

Control method of processing equipment for extended rolling stock

technical field

The invention relates to a control method for a processing plant for elongated rolling stock, especially strip-shaped rolling stock,

- wherein the processing plant has at least one preceding plant part and one downstream plant part, which are passed through directly in sequence by the rolling stock,

- wherein the preceding or downstream plant part is configured as a finishing mill train in which the rolling stock is rolled with a reduced cross-section, and the other plant part is designed in conjunction with the The different equipment components of the finishing mill listed above,

- correspondingly predefine at least one final variable to a control device for the processing plant for a section of the rolling stock passing through the processing plant,

- wherein the respective final variable is derived from a respective desired final state which the respective section of the rolling stock is to have after passing through downstream plant components.

Furthermore, the invention relates to a computer program having a machine code which can be executed directly by a control device of a processing plant for rolling stock, in particular strip-shaped rolling stock, and by which the machine is executed. The code causes the control device to execute such a control method.

Furthermore, the invention relates to a control device for a processing plant for rolling stock, in particular strip-shaped rolling stock, which is designed in such a way that it executes such a control method during operation.

Background technique

The themes mentioned at the outset are well known. Reference is here made purely by way of example to DE 101 56 008 A1 or the corresponding US 7,197,802 B2. Mention may also be made in this connection of EP 1 596 999 B1 or the corresponding US 7,251,971 B2 and US 7,310,981 B2.

With prior art control methods, each plant component is usually controlled individually. If—purely by way of example—the upstream plant part is designed as a finishing train and the downstream plant part is designed as a cooling section, the finishing train is usually operated in the prior art in such a way that the rolled stock The section at the exit of the finishing train (=entrance of the cooling section) has a predetermined finishing temperature. In the cooling section, the section of the rolling stock is then cooled in such a way that the section of the rolling stock leaves the cooling section at a predetermined coiling temperature. In the prior art, the coordination of the operation of the two plant components takes place only by measuring the finishing temperature of the respective section and using it as a starting value for the respective section. The finishing temperature is predetermined for the cooling section.

The above-mentioned prior art approach already represents an improvement over conventional prior art. For this state of the art, the control of the cross-plant components of the processing plant takes place. In particular, the temperature expected for each section of the rolling stock, which is ascertained by means of the model spanning the plant components, can be adjusted in a cycled manner. With the aid of the corresponding expected temperature and the corresponding target temperature, in the prior art a corresponding control variable is ascertained which is to be output to the device which influences the state of the particular section of the rolling stock.

In this case, the control variable for the individual devices is ascertained by means of a control variable ascertainer, which can be designed as a conventional controller, for example, as a P, PI or PID controller device. It is also known from the mentioned prior art to design the controller as a predictive controller which has a predictive level. In particular the last-mentioned procedure already leads to better results. However, the last mentioned processing method, especially the design scheme for obtaining the control quantity, still needs to be improved. The object of the invention is to carry out a correspondingly improved control variable determination.

Contents of the invention

This object is achieved by a control method having the features of claim 1 . Advantageous refinements of the control method according to the invention are the subject matter of subclaims 2 to 12 .

According to the invention it is provided in addition to the features mentioned at the outset that

- said control device implements at least one control variable seeker,

- said control variable elicitor outputs the control variable to at least one device which influences the state of at least one of the sections of the rolled stock passing through the processing plant,

- the control variable ascertainer outputs the control variable at the moment when the at least one section is located in the preceding system part,

- when ascertaining the control variable, the control variable ascertainer takes into account the model-supported expected value of at least one section of the rolling stock within the first prediction period of the corresponding regulator state within,

- the first prediction period is determined in such a way that the control variable elicitor takes into account at least one predicted state for at least one section of the rolling stock when determining the control variable output by it, for the This state is expected for at least one section of the rolling stock in the downstream plant component.

In a possible design scheme of the present invention, it is stipulated that,

- the control device realizes for each section of the rolling stock a respective control variable elicitor, which controls the entire passage of the corresponding section of the rolling stock through the processing plant The control variable elicitor as local remains coupled to the corresponding section of the rolling stock, and

- When the corresponding device acts on the corresponding section of the rolling piece, the corresponding local control quantity obtainer will output the control quantity to the state of the rolling piece passing through the processing equipment locally device to be affected.

This simplifies the control variable determination process.

Provision is preferably made in this refinement that at least one device which locally influences the state of the rolling stock passing through the processing plant is arranged in the upstream plant part.

Optionally, the control device can be configured as a unified control device that controls the entire processing device instead of being divided into a plurality of sub-control devices, or can be divided into a plurality of sub-control devices. In the last-mentioned case, the corresponding control variable ascertainer is preferably realized on the same control sub-device throughout the entire passage of the respective section of the rolling stock through the processing plant.

As an alternative or in addition to the local control variable finder, the control device can realize a control variable finder for all sections of the rolling stock, which acts as a global control variable finder for The mass flow of the rolling stock is affected.

If not only the global control variable finder but also the local control variable finder are implemented, it is preferably specified that

- The controlled variables determined by the local controlled variable determiner in the manner explained above are initially temporary controlled variables, wherein the local controlled variable determiner does not change the mass flow curve currently generated Assuming that the temporary control quantity is obtained,

- the global control variable finder obtains a new mass flow curve by means of input parameters,

- the input variables include at least a temporary control variable determined by a local control variable finder and at least one evaluation variable for the temporary control variable, wherein the evaluation variable is the smallest possible control variable, the maximum the possible control quantity, the maximum possible control quantity change, or an intermediate value between the minimum possible control quantity and the maximum possible control quantity, and

- The local control variable ascertainer determines its final control variable using the provisional control variable, the currently generated mass flow curve and the new mass flow curve.

Other input parameters of the global control variable finder can be determined as required. It is preferably provided that the input variable can also include the desired state of at least one section of the rolling stock that has not yet entered the upstream plant part, and/or for this section of the rolling stock a corresponding The expected temporary control quantity obtained by the local control quantity obtainer and the corresponding evaluation parameter.

Usually, the at least one control variable ascertainer outputs a control variable at multiple instants in each case to a device which influences the state of at least one of the sections of the rolling stock passing through the processing installation. In this case, often the time interval between the first and the second of said times is smaller than the first forecast period. It can thus be achieved that the at least one control variable ascertainment unit determines the control variable expected for the second of the times in order to determine the control variable output at the first of the times , and this expected control variable is taken into account when ascertaining the predicted state which is temporally after a second of the times but is still within the first prediction period. In particular, the at least one controlled variable ascertainer can be designed as a model-predictive controller.

The first forecast period can be determined as needed. In particular, the first forecast period can be determined such that it extends at least from the state in which the rolling stock in the upstream plant part is first affected until the rolling stock emerges from the downstream plant part.

In the case described so far, the prediction only concerns individual sections of the rolling stock. The control method can be further improved in that the control device ascertains, for at least one of the devices influencing the state of the rolling stock, the expected state of the respective device within the second forecast period, and the resulting The control device takes into account the expected state of the respective device in the second forecast period when ascertaining the control variable output by the controlled variable determiner to the respective device.

In a preferred refinement of the control method according to the invention, the at least one control variable ascertainer determines the control variable by optimizing (ie maximizing or minimizing) an objective function, In this case, besides the deviation of the predicted state of the at least one section of the rolling stock from the corresponding setpoint state, the energy consumption of the processing plant is also included in the objective function. By means of this treatment, the energy requirement of the treatment plant can be reduced and possibly even minimized.

The finishing train generally has a plurality of rolling stands, and the rolling stands are sequentially passed through by the rolling stock during the process of the rolling stock passing through the finishing mill train. The control method according to the invention can also be used, in particular, upstream of the first passing rolling stand of the finishing rolling train and if no cooling device is arranged between the rolling stands of the finishing rolling mill train.

It can be arranged that the upstream installation part is designed as a finishing train and the downstream installation part is designed as a cooling section. In another possible configuration, the downstream plant component is designed as a finishing train. In this case, the upstream system part is preferably designed as a furnace, for example as an induction furnace. In particular, the control method according to the invention can also be used in a configuration of the treatment plant in which a roughing train is arranged upstream of the furnace and a roughing train is arranged upstream of the roughing train. The continuous casting plant and the plant are operated at a casting speed, so that the rate at which the rolling stock enters the finishing train is determined by the casting speed and the cross-sectional reduction of the rolling stock in the roughing train.

Furthermore, the object is solved by a computer program of the type mentioned at the outset, the machine code of which is designed in such a way that the execution of the machine code by the control unit causes the control unit to execute the computer program according to the invention. control method. In particular, the computer program can be stored on a data carrier in machine-readable form, in particular only in machine-readable form, for example electronically.

Furthermore, the object is solved by a control device for a processing plant for rolling stock, in particular strip-shaped rolling stock, which is designed in such a way that it executes the control method according to the invention during operation.

Description of drawings

Additional advantages and details emerge from the following description of exemplary embodiments with reference to the drawings. Accompanying drawing shows as follows with principle diagram:

Fig. 1 is a schematic diagram of the processing equipment for rolling stock;

Figures 2 to 5 are possible designs of the processing equipment of Figure 1;

Figures 6 to 9 are flowcharts and

10 and 11 show possible configurations of the control device.

Detailed ways

According to FIG. 1 , the processing plant for an extended rolling stock 1 has upstream and downstream plant parts 2 , 3 . The preceding and downstream plant parts 2 , 3 are passed directly sequentially by the rolling stock 1 . The rolling stock 1 can in particular be a strip-shaped rolling stock. It is generally made of metal, such as steel, aluminum, copper, brass or other non-ferrous metals.

The upstream or downstream plant parts 2 , 3 are designed as finishing trains. In the embodiments of FIGS. 2 and 3 , the upstream plant part 2 is designed as a finishing train. In the refinement according to FIGS. 4 and 5 , the downstream plant part 3 is designed as a finishing train.

Regardless of whether the upstream or downstream plant parts 2 , 3 are configured as a finishing train, the finishing train generally has a plurality of rolling stands 4 , which During the process of the rolling stock 1 passing through the finishing mill row, the rolling stock passes through it successively. The rolling stock 1 is rolled with a reduced cross-section in the rolling stands 4 of the finishing train. The number of rolling stands 4 is generally between 4 and 8, for example 6 or 7. As an alternative, reversible rolling can be performed. In this case, there is usually a single rolling stand 4 .

The further plant part 3 , 2 is designed as a different plant part than the finishing train. According to FIGS. 2 and 3 , the downstream system part is designed as a cooling section with a roller table 5 and a cooling device 6 . In the cooling section, the cross-section of the rolling stock 1 (apart from the thermal contraction) no longer changes. That is to say no deformation of the rolling stock 1 takes place in the cooling section. According to FIGS. 4 and 5 , the upstream system part 2 is designed as a furnace, for example as an induction furnace.

As indicated by the dashed lines in FIG. 1 , it can be arranged that a further equipment part 7 is arranged in front of the upstream equipment part 2 itself. For example, in the embodiments of FIGS. 2 and 3 , a furnace and/or other components are additionally arranged upstream of the finishing train. In the configuration according to FIG. 5 , for example, a roughing train is arranged upstream of the furnace as a further plant part 7 . A continuous casting installation 8 is again arranged upstream of the roughing train.

According to the schematic diagram shown in dashed lines in FIG. 1 , further equipment parts 9 can likewise be arranged behind the downstream equipment part 3 . For example, in the refinement of FIG. 4 , a cooling section can be arranged downstream of the finishing train as a further plant component 9 .

Said further plant components 7, 9 can be incorporated together into a control scheme explained in detail below. As an alternative, only the upstream and downstream system components 2 , 3 can be operated in the manner according to the invention and the further system components 7 , 9 can be operated in a different manner.

The boundaries between the device parts 8 , 7 , 2 , 3 , 9 can be determined according to requirements. In particular, the boundary between the device parts 8 , 7 , 2 , 3 , 9 can lie between the last active element of the respectively upstream device part 8 , 7 , 2 , 3 and the respectively downstream device part 7 , 2 , 3 , between the first valid element of 9. The boundary between the furnace and the installation part 7 arranged upstream of the furnace, such as the roughing train 7 , is thus between the last stand of the roughing train 7 and the first heating device 18 of the furnace. In a similar manner, the boundary between the furnace and the finishing train is between the last heating device 18 of the furnace and the first stand 4 of the finishing train. The boundary line between the finishing train and the cooling section is between the last rolling stand 4 of the finishing train and the first cooling device 6 of the cooling section. If a temperature measuring point 19 (or another measuring station, for example for strip thickness or strip shape) is arranged between every two plant parts 8 , 7 , 2 , 3 , 9 directly following one another, The position of the corresponding measuring device 19 then preferably represents the boundary between the plant parts 8 , 7 , 2 , 3 , 9 .

The processing device of FIGS. 1 to 5 is controlled by a control device 10 (shown only in FIG. 1 ). The control device 10 is generally designed as a software-programmable control device. This is shown in FIG. 1 in that the letter “μp” is written inside the control unit 10 , and the mode of operation of the control unit 10 is thus determined by the computer program 11 . The computer program 11 has a machine code 12 which can be executed directly by the control device 10 . The machine code 12 is executed by the control device 10 so that the control device 10 executes a control method which will be explained in detail below. Due to the execution of the machine code 12 , the control device 10 is designed such that it executes the control method according to the invention during operation.

The computer program 11 can be supplied to the control device 10 in any desired manner, for example via a computer-to-computer connection. In particular, transmission via the Internet or a local area network is conceivable. Alternatively, the computer program 11 can be delivered to the control device 10 via a removable data carrier 13 on which the computer program 11 is stored in a machine-readable form. The removable data carrier 13 is shown here purely by way of example in FIG. 1 as a USB memory stick. However, the mobile data carrier can also be embodied in other forms.

A possible control method according to the invention is explained below with reference to FIG. 6 .

According to FIG. 6 , in step S1 the current state Z of the rolling stock 1 and the current position of the point 14 are fed to the control unit 10 . The current location is based on the processing facility. The current position is at the beginning of the upstream plant part 2 , that is, for example in front of the first rolling stand 4 of the finishing train in the embodiment of FIGS. 2 and 3 . If the finishing train has an intermediate stand cooling device 15 according to the schematic illustration in FIG. The location can also be upstream of this intercooler 15 . If necessary, this position can also be in a more forward position.

In the case of other configurations of the processing plant, such as the configuration according to FIG. 4 , the locations are arranged elsewhere. If, for example, a furnace arranged in front of the finishing train is also included in the control method according to the invention, then the position must be before the furnace, to be more precise in the first position of the furnace. A heating device 18 before. In general, it applies that the position must be arranged before the start of the first plant component incorporated into the control method according to the invention or further forward.

State Z can be predetermined for control device 10 from the outside or in another way. Alternatively, state Z can be detected by means of measurement technology. Mixed forms can also be considered. For example, in order to determine the energy state of the relevant point 14, a temperature measuring point 19 can be arranged at the current position, by means of which temperature measuring point is on the surface of the rolling stock 1 to detect the current state of the point 14 of the rolling stock 1. temperature T. Viewed in the thickness range of the rolling stock 1 , the temperature profile can be determined, for example, by means of a model. Such models are generally known to those skilled in the art.

It is possible that the energy state is already completely described by the temperature T of the point 14 . In practice, the temperature T is often in a range within which it can be determined unambiguously by means of the temperature in which phase the rolling stock 1 is in. For example, when rolling steel, the temperature at the entrance to the finishing train is generally about 1000° C. or higher and is thus well above the phase transformation temperature of the steel (approximately 723° C. to 911° C.). It is thus known that the rolling stock 1 is in the phase "austenite" in this case.

The dimensions of rolling stock 1 , such as strip thickness and strip width for strip-shaped rolling stock, can be ascertained in other ways or known to control device 10 in other ways.

In step S2 , the control device 10 ascertains the desired final variable with the aid of the desired final state Z*, the point 14 should have the desired final state Z* after passing through the downstream system part 3 . For example, the control device 10 can ascertain the desired final enthalpy, the desired final temperature, the desired phase fraction of the rolling stock 1 , eg for steel the fraction of austenite, etc. As an alternative to ascertaining the final variable, it is also possible to predetermine the desired final variable for the control device 10 .

In step S3 , control device 10 implements control variable ascertainer 16 for detected point 14 (see FIGS. 10 and 11 ). Control variable ascertainer 16 is initialized and started with state Z of respective point 14 within the scope of step S3 . The control variable ascertainer 16 is coupled as a local control variable ascertainer 16 to the corresponding point 14 of the rolling stock 1 . The control variable ascertainer remains coupled to this point 14 throughout its entire passage through the processing device.

The realized local control variable ascertainer 16 always outputs the control variable S to the devices of the processing plant when the corresponding device acts on the corresponding point 14 of the rolling stock 1 . The corresponding devices influence the state Z of the rolling stock 1 passing through the processing plant only locally, ie at the point where the corresponding device is arranged. At the moment when the relevant device acts on the relevant point 14 of the rolling stock 1, other regions of the rolling stock 1 are not affected by this device, although they may be affected by other devices.

The individual devices of the processing plant—such as the cooling device 6 and the intermediate stand cooling device 15 of FIG. 2 or the heating device 18 of the furnace of FIG. 4—act on the corresponding point 14 of the rolling stock 1. ask for. In particular - as is known to those skilled in the art - travel tracking can be implemented.

In step S4 , the local controlled variable ascertainer 16 determines a temporary controlled variable profile. In step S5, the local control variable ascertainer 16 determines the expected position of the corresponding point 14 within the forecast period by means of the model 17 of the rolling stock 1 realized inside the control device 10 The expected state at the end of the forecast period. The local control variable finder 16 obtains the expected state of the corresponding point 14 under the assumption that the currently generated mass flow curve does not change, and the corresponding point 14 is currently and will be expected to be at the current The resulting mass flow profile is passed through the processing equipment.

Usually time-based differential equations must be solved to obtain the desired state. In this case, it is necessary to adjust the states at small temporal intervals. In this case, therefore, the entire state change curve is ascertained.

The corresponding model 17 is known as such a model and is not the subject of the present invention. The model 17 is based on Fourier's heat conduction equation, phase transition model, heat transfer model, rolling model, etc.

Within the scope of the prediction, the local control variable ascertainer 16 takes into account the control variable S on the one hand, which the local control variable ascertainer 16 uses as a next step to control the state of the corresponding point 14 One of the devices that Z influences.

In individual cases—for example when only a single heating device 18 is present—the local controlled variable ascertainer 16 outputs the controlled variable S only at a single instant. Usually, however, local control variable ascertainers 16 each output a control variable S at several times to the device which affects exactly the corresponding point 14 of the rolling stock 1 . If the time interval between other moments and the current moment (the local control quantity obtainer outputs its control quantity S at the current moment) is less than the prediction period of the local control quantity obtainer 16, then the The local control variable ascertainer 16 not only determines the control variable S to be output next, but also outputs an expected control variable for each other time within the forecast period. The local control variable ascertainer 16 here takes as a starting point the fact that the current mass flow profile with which the point 14 under investigation is and will be expected to pass through the process has not changed equipment. The local control variable ascertainer 16 naturally takes the ascertained expected control variable into account when ascertaining the expected state of the respective point 14 of the rolling stock 1 at the end of the forecast period. For this purpose, local control variable ascertainer 16 can in particular be designed as a model-predictive regulator.

In step S5 , the local control variable obtainer 16 obtains its control variable S by optimizing (ie, minimizing or maximizing) the objective function. Of course, the deviation of the predicted state of the point 14 of the rolling stock 1 from the corresponding setpoint state is added to the objective function. Alternatively, the state itself or variables derived from the state can be used here.

In addition to the desired end state, it is also possible for the control device 10 to predetermine for other positions of the processing plant and/or for a specific time calculated since the entry of the corresponding point 14 of the rolling stock 1 into the processing plant. Given the desired intermediate state. If this is the case, then of course the corresponding desired intermediate variable is ascertained for the respective position and/or time and taken into account when ascertaining the control variable S of the local control variable ascertainer 16 .

The objective function is usually a function with multiple variables. The objective function is minimized (or maximized) according to the SQP method. The SQP method is well known to those skilled in the art.

In step S7 , the local control variable ascertainer 16 outputs the control variable S determined therefrom to be output currently to a corresponding device, by means of which the state Z of the relevant point 14 can be currently influenced. Control device 10 ascertains corresponding devices, for example by means of the already mentioned path tracking. Furthermore, the respective local control variable ascertainer 16 updates the state Z of the point 14 assigned to it.

As already mentioned and also shown in FIG. 2 , local control variable ascertainer 16 acts on cooling devices 6 , 15 , for example. The cooling device can be arranged in the cooling section of FIG. 2 . As an alternative or in addition, the cooling device can be arranged in the finishing train, that is to say in the upstream installation part 2 according to FIG. 2 . Likewise, for example, in the embodiments of FIGS. 4 and 5 , the local control variable ascertainer 16 can act on the heating device 18 of the furnace. In this case, the corresponding device is thus arranged in the upstream system part 2 .

The prediction period of the local control variable ascertainer 16 is suitably determined. In particular, the forecast period is determined such that for typical rolling stock speeds, the local control variable determiner 16 controls the devices located in the upstream equipment part 2 (for example, in the configuration according to FIG. 2 ). Control one of the intermediate rack cooling devices 15 in the scheme or control one of the heating devices 18 of the furnace in the configuration according to FIG. 4 ), the local control variable determiner 16 takes into account the The predicted state of the respective point 14 of the rolling stock 1 has the predicted state only if the respective point 14 of the rolling stock 1 is located in the downstream plant part 3 .

This fact is shown visually in FIG. 2 by plotting the different possible forecast periods purely by way of example. The possible forecast periods are indicated in FIG. 2 with the reference numerals PH1 to PH3.

According to the forecast period PH1, the local control variable ascertainer 16 takes into account the corresponding control variable S of the rolling stock 1 when it determines the control variable S for the last intermediate stand cooling device 15 of the finishing train. The desired state of a point 14, which corresponding point 14 has the desired state only in the cooling section. According to the prediction period PH2 , this is already the case when the local control variable ascertainer 16 determines the control variable S for the penultimate intermediate rack cooling device 15 . According to the forecast period PH3, the forecast period can even be determined in such a way that it starts from the preceding plant part 2 (that is, for example, in FIG. In the cooling device 15 , in the configuration according to FIG. 4 in the first heating device 18 ), the state of the rolling stock 1 is first influenced until the rolling stock 1 is removed from the downstream plant part 3 come out. A similar implementation also applies, of course, to the configurations of the treatment plant according to FIGS. 3 , 4 and 5 .

The forecast period can be static or dynamic. Preferably, the forecast period is static at the beginning of the forecast until the forecast period reaches the end of the downstream plant component 3 (or usually the last plant component incorporated into the control method according to the invention). end. The prediction period is then preferably shortened dynamically so that it extends from the respective current position of the point 14 assigned to the respective local control variable ascertainer 16 to the end of the downstream system part 3 . In this case it is possible to introduce a predictive period like a telescopic rod, for which one end is connected to the point 14 assigned to the corresponding local control variable determiner 16 and the other end " into the future". The telescopic rod remains pulled out until the other end "touches" the end of the rear-mounted equipment part 3 . The telescoping rod is then correspondingly "shortened".

In steps S8 and S9, the control device 10 checks whether the relevant point 14 has come out of the downstream system part 3, that is to say, for example, in the configuration of FIG. 2 has left the cooling section. . If this is not the case, the control device 10 returns to step S4. If this is the case, the control device 10 goes to step S10. In step S10 , control device 10 deletes local control variable ascertainer 16 realized for outgoing point 14 . At least within the scope of the control method according to the invention, the outgoing point 14 is no longer considered.

Optionally between the individual plant parts 2, 3 and/or behind the downstream plant part 3—that is, according to the configuration of FIG. 2, for example between the finishing train and the cooling section and /Or behind the cooling section-an additional measuring device 19 is arranged, by means of which other measuring device is used to detect the variable G related to the desired final variable, such as the corresponding point 14 of the rolling stock 1 temperature T. In this way, for example, the model 17 can be adapted. Corresponding treatments are known as such and are not the subject-matter of the present invention.

The method of FIG. 6 is executed in a tick mode. For example, a corresponding detection of a new point 14 of the rolling stock 1 takes place with a cycle time which usually lies between 0.1 and 1.0 seconds. A preferred value for the duty cycle is between 0.2 and 0.5 seconds, for example approximately 0.3 seconds. The control device 10 thus executes the method explained above in conjunction with FIG. 6 in parallel for all points 14 present in the processing plant at a particular time.

Furthermore, the rolling stock 1 has a—constant or variable—inlet velocity v when it enters the upstream plant part 2 . Each of the points 14 thus corresponds to a section of the rolling stock 1 whose length is the product of the working cycle and the current inlet velocity v, the corresponding point 14 being represented by the The current inlet velocity v enters the upstream system part 2 .

The method explained below in connection with FIG. 7 is preferably used in the configuration of the processing plant according to FIG. 2 or 3 . The method has steps S11 to S24. Steps S11 to S20 correspond to steps S1 to S10 of FIG. 6 at a ratio of 1:1. Therefore, no more detailed explanation is needed regarding steps S11 to S20.

In step S21 , the control device 10 implements a global control variable ascertainer 20 (see FIGS. 10 and 11 ). Global control variable ascertainer 20 acts on the mass flow of rolling stock 1 and thus simultaneously on all points 14 /sections 14 of rolling stock 1 . Global control variable ascertainer 20 is integrated into the control method according to the invention via steps S22 and S23 .

In step S22, the global control variable obtainer 20 obtains a new mass flow curve. The ascertainment process here takes place using the controlled variable S ascertained in step S16 by the local controlled variable ascertainer 16 . Within the scope of step S22, global control variable ascertainer 20 preferably takes into account not only control variable S to be output by local control variable ascertainer 16 in step S17, but also The expected control variable obtained by the obtainer 16 is within the prediction period of the local control variable obtainr 16 .

Global controlled variable ascertainer 20 evaluates controlled variable S of local controlled variable ascertainer 16 within the scope of step S22 using at least one evaluation variable. Both the evaluation variable and the controlled variable S ascertained by the local controlled variable ascertainer 16 thus represent the input variable for the global controlled variable ascertainer 20 . The evaluation variable can be (for each local controlled variable ascertainer 16 ) in particular at least one of the following variables:

- the smallest possible amount of control,

- the maximum possible amount of control,

- an intermediate value between the smallest possible amount of control and the largest possible amount of control, and

- Maximum possible control volume change.

The first three of the mentioned variables are based on the means 6, 15, 18 respectively for each control variable (it does not matter whether it is to be output in step S15 or only within the forecast period), the corresponding local control variable The ascertainer 16 acts on the devices 6 , 15 , 18 at the respective output times. It only makes sense to take into account the maximum possible variation of the controlled variable when the global controlled variable ascertainer 20 correlates the plurality of controlled variables S, which are determined by The same local control variable finder 16 or multiple local control variable finders 16 successively output to the same device 6 , 15 , 18 .

In particular, the global control variable ascertainer 20 can create an objective function and optimize it similarly to the local control variable ascertainer 16 . In particular, the objective function may contain a penalty term (Strafterme), and the penalty term is used to punish,

- if the control variable S of the local control variable finder 16 is close to the minimum regulation limit and/or the maximum regulation limit,

- if the control variable S of the local control variable elicitor 16 is too far from the intermediate value and/or

- The required control variable change is close to the maximum possible control variable change.

The control variable S' of the global control variable ascertainer 20 can also be evaluated in a similar manner.

By changing the mass flow curve, global manipulated variable ascertainer 20 attempts to optimize the evaluation in step S22 . For example, the global control variable finder 20 attempts to keep the expected control variable S to be output by the local control variable finder 16 within a permissible range, as far as possible from the regulation limit and Keep the desired rate of change within allowable limits. At the same time, global control variable ascertainer 20 takes into account the corresponding limits for the mass flow. Global control variable ascertainer 20 can also be designed as a model-predictive regulator.

In step S23, the local control quantity obtainer 16 calculates its final control quantity S by means of the control quantity of the mass flow curve newly obtained in step S22 and the previously applicable mass flow curve. . In step S16, the local control variable ascertainer has to calculate the expected state of the corresponding section 14 of the rolling stock 1 up to its forecast period. Contrary to the step S16, in step S20 only calibration The control quantity S currently to be output may suffice. However a complete recalculation is not excluded. Without depending on the specific processing method, since the control variable S is changed in step S23, the control variable S obtained in step S16 is only a temporary control variable S.

In step S17 , only the local control variable ascertainer 16 outputs its control variable S to the corresponding device 6 , 15 , 18 . In step S24, which is carried out almost simultaneously with step S17, the global control variable ascertainer 20 outputs a corresponding control to an actuator for the mass flow, for example to the rotational speed controller 21 for the rolling stand 4 Volume S'.

The procedure described in conjunction with FIG. 7 is particularly relevant when, according to FIG. 3 , no intermediate rack cooling device 15 is present. However, this procedure can only be carried out if the intermediate rack cooling device 15 is present. However, irrespective of whether the intercooler 15 is present, at the moment when a plurality of segments 14 are located in the upstream plant part 2 (according to FIGS. 2 and 3 , for example a finishing train), the The global control variable obtainer 20 outputs its control variable S'.

Similar to local controlled variable ascertainer 16 , global controlled variable ascertainer 20 also has a forecast period. The prediction period is similar to that in Fig. 2 and can be determined as required. It can be the same as or different from the forecast period of the local control variable ascertainer 16 . FIG. 3 —purely exemplary—shows several possible prediction periods of global control variable ascertainer 20 , which are indicated by PH4 and PH5 in FIG. 3 . The minimum forecast period (see forecast period PH4) extends from the beginning of the upstream equipment part 2 to the first device 6 of the downstream equipment part 3, by means of which it is possible to The state of the rolling stock 1 is locally influenced. The maximum forecast period (see forecast period PH5) extends completely from the beginning of the preceding plant part 2 to the end of the downstream plant part 3, that is to say as far as the rolling stock 1 from the Out of the above-mentioned post-installed equipment part 3. Larger forecast periods can also be considered. A similar implementation also applies, of course, to the refinement of the treatment plant according to FIGS. 2 and 4 .

If a global control variable ascertainer 20 is present, it is even possible that the input variables of the global control variable ascertainer 20 can also include the rolling stock 1 which has not yet entered the upstream plant part 2 The expected state of segment 14. It is only necessary for this to be realized, initialized and activated in advance for each segment 14 in advance of the corresponding local control variable ascertainer 16 . As long as this local control variable ascertainer 16 continues to ascertain the already expected local control variable for the section 14 of the rolling stock 1 that has not yet entered the upstream plant part 2 , the global control variable The input variables of the ascertainer 20 also include these expected control variables and corresponding evaluation variables.

The processing method of FIG. 7 can also be used in the processing device according to FIG. 2 . It can also be used on processing devices according to FIG. 4 .

As described above, when determining the control variable S' of the global control variable determiner 20 and the control variable S of the local control variable determiner 16, the sections of the rolling stock 1 are carried out 14 Prediction of state Z. It can additionally be arranged that the control device 20 determines the corresponding device 6 , 15 , 18 , 21 for at least one of the devices 6 , 15 , 18 , 21 influencing the state Z of the rolling stock 1 The expected state within another (second) prediction period, and when obtaining the control quantities S, S' takes into account the expected state of the respective device 6 , 15 , 18 , 21 in this forecast period. This is explained in more detail below in conjunction with FIGS. 8 and 9 . In this case, FIG. 8 shows a possible configuration of FIG. 6 , and FIG. 9 shows a possible configuration of FIG. 7 .

According to FIG. 8 , additional steps S31 and S32 are inserted between steps S6 and S7 . In step S31 , the control device 10 ascertains its desired state for at least one of the devices 6 , 15 , 18 influenced by the local control variable ascertainer 16 . In step S32 , the control device 10 outputs to the device 6 from the local control variable ascertainer 16 , taking into account the expected state of the corresponding device 6 , 15 , 18 as far as necessary. , 15, 18 of the control amount S to be corrected.

The processing method of FIG. 8 will be explained in detail below by means of a simple embodiment.

It is assumed here that a specific cooling device 6 of the cooling section supplies a specific section 14 of the rolling stock 1 with coolant (for example water) in a specific operating cycle of the control device 10 . In the next working cycle, the same cooling device 6 acts as coolant to the next segment 14 , and in the next working cycle to the next segment 14 as well.

The local control variable ascertainer 16 , which determines 80% as a relative control variable, acts on the cooling device mentioned in a specific operating cycle. The next and next local control variable ascertainers 16 assigned to the two subsequent sections 14 of the rolling stock 1 determine 50% and 20% as expected control variables. Furthermore, it is assumed that the cooling device 6 following the first-mentioned cooling device 6 is to be controlled by the three just-mentioned local control variable determiners with 60%, 60% and 40%. Furthermore, it is assumed that the cooling devices 6 are of uniform design and can vary their coolant flow rate by a maximum of 25% from cycle to cycle.

If steps S31 and S32 were absent under the above-mentioned assumptions, only the segments 6 that first pass through the two cooling devices 6 are cooled with exactly 80% and 60%. However, the second section can only be cooled by the first cooling device with only 55%, since the first cooling device 6 cannot throttle the coolant flow any faster starting from 80%. The error is thus 5%. The next zone is cooled with 30% instead of 20%. The reason is the same: the corresponding cooling device 6 can only throttle the coolant flow from 55% to 30%.

However, the coolant can be changed intelligently, taking into account the state of the cooling device 6 and in particular its adjustment options (minimum and maximum coolant flow, maximum change in coolant flow per cycle) flow, so that, for example, the first section 14 is cooled with 75% and 65% by the two considered cooling devices 6, the second section is cooled with 50% and 60%, and with The third section 14 is cooled at 25% and 35%. As a result, it is thus achieved that—viewed by the two cooling devices 6—three sections 14 of the rolling stock are consequently cooled with the correct amount of coolant. Thus, by suitable changes in the amount of coolant, optimization can be performed.

In a similar manner, steps S41 and S42 may follow step S16 in the processing according to FIG. 9 . The contents of steps S41 and S42 are equivalent to steps S31 and S32 in FIG. 8 .

As an alternative or in addition, there may be steps S43 and S44 which are inserted after step S23. Steps S43 and S44 may be equivalent to steps S31 and S32 of FIG. 8 in content. In addition to steps S41 and S42 , the presence of steps S43 and S44 is particularly meaningful because the control variable S of the local control variable determiner 16 described in step S22 may have changed.

Furthermore, it may make sense to arrange steps S45 and S46 after step S22. In steps S45 and S46 , a procedure similar to steps S31 and S32 is carried out for the actuator 21 for the mass flow.

As already mentioned, the control variable ascertainers 16, 20 usually determine their corresponding control variables S, S' by optimizing the corresponding objective function. In addition to the deviation of the predicted state from the corresponding nominal state, preferably one or more of the following variables can be added to the objective function:

- the distance between the control variables S, S' and the regulation boundaries (minimum and maximum values) of the devices 6, 15, 18, 21 controlled by the corresponding control variable finders 16, 20;

- the deviation of the output and future expected control variables S, S' from the intermediate value, which is mostly approximately in the center between the control boundaries of the corresponding device 6, 15, 18, 21;

- Possibly, for the corresponding device 6, 15, 18, 21, the distance between the expected control variable change and the maximum possible rate of change of the control variable S, S';

- the maximum permissible temperature of the rolling stock 1 and the distance between the actual temperature T and this value, especially in the case where the processing plant has a furnace;

- The total energy consumption of the treatment plant.

The smaller the deviation of the expected state within the forecast period PH1 to PH5 and/or at the end of said forecast period PH1 to PH5 from the corresponding nominal state, the better (naturally) the solution to the target function. As long as one or more of the other parameters mentioned above are considered, then

- the farther the output and future control variable S, S' is from the control limit of the correspondingly controlled device 6, 15, 18, 21,

- the closer the deviation of the output and expected control variables S, S' is to the middle value and/or

- The farther the required change speed is from the maximum possible change speed of the output and future control variables S, S',

The better the objective function is solved.

As an alternative or supplementary-preferred alternative to taking into account the maximum possible rate of change of the control limit and the control variables S, S', corresponding equations and inequality additional conditions can be established as a supplement to the objective function. In this case, the additional conditions are taken into account within the framework of the optimization (=maximization or minimization) of the objective function. For example, when optimizing the objective function, it is possible to establish additional conditions that should be taken care of, namely that the cooling by the cooling device 6 , 15 may not be negative and does not exceed a certain (plant-specific, if necessary also dynamic) maximum value . The mentioned SQP method is able to take such additional conditions into account.

The control device 10 implementing the control method according to the invention must have high computational efficiency. This computing efficiency can be achieved according to the schematic diagram of FIG. 10 in a single unified control device 10 , which controls the entire processing plant, and is not divided into a plurality of sub-control devices. As an alternative, the control device 10 can be divided into a plurality of sub-control devices 22 according to the schematic diagram of FIG. 11 . If such a division is made, however, preferably each implemented local control variable ascertainer 16 is located on the same sub-control device 22 during the entire passage of the corresponding section 14 of the rolling stock 1 through the processing plant. accomplish. It is therefore preferably not the case that the corresponding local control variable ascertainer 16 passes, for example, from the sub-control unit 22 shown on the left in FIG. 11 to the sub-control unit 22 shown on the right in FIG. 11 if— For example, the corresponding section 14 of the rolling stock 1 is transferred from the upstream plant part 2 into the downstream plant part 3 .

The processing explained above can also be applied in a similar manner to the embodiment of the processing plant according to FIGS. 4 and 5 . The only essential difference is that the section 14 of the rolling stock 1 is not cooled but heated by means of the heating device 18 of the furnace.

The present invention has many advantages. In particular, for the first time predictions across plant components are possible. Because in the prior art model estimation and thus forecasting is already used. In the prior art, however, the prediction is always limited to the respective plant part 2 , 3 .

In addition, especially in the configuration of the treatment plant according to FIGS. 4 and 5 , the furnace as upstream plant part 2 can be used for adjusting the finish rolling temperature at the outlet of the finishing train train as downstream plant part 3 . For this purpose, the forecast period simply has to be chosen sufficiently large.

This configuration is particularly decisive if, on the one hand, there is no intermediate stand cooling device 15 in the finishing train and, on the other hand, the entry velocity v is determined for technical reasons, the rolling stock 1 The entry velocity v enters the finishing train. Since there are then no actuators available inside the finishing train, by means of which the finishing temperature at the outlet of the finishing train can be adjusted here. However, the furnace (=upstream plant part 2 ) can be used to adjust the finish rolling temperature (not the entry temperature at the entry of the finishing train) accordingly by means of the procedure according to the invention.

The rolling stock 1 enters the finishing train with an entry velocity v, which can be determined, for example, because the schematic diagram according to FIG. The device 7 is arranged with a roughing train and, on the other hand, a continuous casting installation 8 is arranged upstream of the roughing train. This is because the casting speed of the continuous casting plant 8 is essentially determined by the solidification properties of the metal being cast and can only be adjusted within narrow limits. The entry velocity v of the rolling stock 1 is determined in this case by a more or less fixed predetermined casting speed and the cross-sectional reduction of the rolling stock 1 in the roughing train.

The above description is only for explaining the present invention. However, the protection scope of the present invention should only be determined by the appended claims.

Claims (15)

1. A control method for a processing plant for extended rolling stock (1), especially strip-shaped rolling stock (1), - wherein the processing plant has at least one preceding plant part (2) and one downstream plant part (3), said plant parts being passed directly sequentially by the rolling stock (1), - wherein the upstream or downstream plant parts ( 2 , 3 ) are designed as finishing trains in which the rolling stock ( 1 ) is rolled with a reduced cross-section, and The other plant part ( 3 , 2 ) is designed as a different plant part than the finishing train, - wherein for a section (14) of the rolling stock (1) passing through the processing plant, a control device (10) for the processing plant is correspondingly predetermined with at least one final variable, - wherein the corresponding final variable is derived from the corresponding desired final state (Z*) of the corresponding section ( 14 ) of the rolling stock ( 1 ) after passing through the downstream plant part ( 3 ) should have the final state (Z*), - wherein said control device (10) implements at least one control variable elicitor (16, 20), - wherein said control variable elicitor (16, 20) influences at least one device ( 6, 15, 18, 21) output control quantity (S, S'), - wherein the control variable ascertainer (16, 20) outputs the control variable (S, S') at the moment when the at least one section (14) is located in the upstream plant part (2), -wherein when determining said control variables (S, S'), said control variable evaluators (16, 20) take into account the in-model support of at least one section (14) of said rolling stock (1) The expected state obtained below is within the first prediction period (PH1 to PH5) of the corresponding control quantity obtainer (16, 20), - wherein the first prediction period (PH1 to PH5) is determined in such a way that the control variable finder (16, 20) takes into account at least one of Predicted state of at least one section (14) of the rolling stock (1) in the downstream plant part (3) for at least one section (14) of the rolling stock (1) Looking forward to that status. 2. by the control method described in claim 1, It is characterized in that, - The control device (10) implements a control variable obtainer (16) for each section (14) of the rolling stock (1), and the control variable obtainer (16) is in the rolling stock (1) The corresponding section (14) of (1) remains coupled to the corresponding section (14) of the rolling stock (1) as a local control variable finder (16) throughout its passage through the processing plant ) on, and - When the corresponding device (6, 15, 18) acts on the corresponding section (14) of the rolling stock (1), the corresponding local control variable obtainer (16) will control the variable (S) output to devices (6, 15, 18) for locally influencing the state (Z) of the rolling stock (1) passing through the processing plant. 3. by the control method described in claim 2, It is characterized in that at least one of the devices ( 15 , 18 ) for locally influencing the state (Z) of the rolling stock ( 1 ) passing through the processing plant is arranged on the upstream plant part ( 2 ) middle. 4. by the control method described in claim 2 or 3, It is characterized in that the control device (10) is configured as a unified control device (10) that controls the entire processing equipment and is not divided into multiple sub-control devices, or the control device (10) is divided into multiple sub-control devices device (22), but the corresponding local control variable obtainer (16) is in the same sub-control device during the entire process of the corresponding section (14) of the rolled product (1) passing through the processing equipment (22) is realized. 5. according to the control method described in any one of the preceding claims, It is characterized in that the control device (10) realizes a control variable obtainer (20) for all sections (14) of the rolling stock (1), and the control variable obtainr (20) serves as a global control variable obtainer (20) The extractor (20) acts on the mass flow of the rolled piece (1). 6. by claim 5 and by the control method described in any one of claim 2,3 and 4, It is characterized in that, - the controlled variable (S) determined by the local controlled variable determiner (16) in the manner explained above is initially a temporary controlled variable (S), wherein the local controlled variable determiner (16 ) to obtain the temporary control quantity (S) under the assumption that the currently generated mass flow curve does not change, - the global control variable obtainer (20) obtains a new mass flow curve by means of input parameters, - said input variables comprise at least a temporary controlled variable (S) ascertained by a local controlled variable finder (16) and at least one evaluation variable for said temporary controlled variable (S), wherein said evaluation the parameter is the minimum possible control quantity, the maximum possible control quantity, the maximum possible control quantity change or an intermediate value between the minimum possible control quantity and the maximum possible control quantity, and - The local control variable ascertainer ( 16 ) determines its final control variable (S) using the provisional control variable (S), the currently generated mass flow curve and the new mass flow curve. 7. by the control method described in claim 6, It is characterized in that the input variables also include the expected state of at least one section (14) of the rolling stock (1) which has not yet entered the upstream plant part (2), and/or for the For this section ( 14 ) of the component ( 2 ), the expected temporary control variable and the corresponding evaluation variable are ascertained by the corresponding local control variable ascertainer ( 16 ). 8. The control method according to any one of the preceding claims, It is characterized in that, - said at least one control variable obtainer (16, 20) outputs a control variable (S, S') respectively at multiple times to a section (14) of a rolling stock (1) passing through the processing plant means (6, 15, 18, 21) to influence the state (Z) of at least one zone in ), - the time interval between the first and the second of said moments is less than the first forecast period (PH1 to PH5), - said at least one control variable obtainer (16, 20) obtains a control variable (S, S') output for a second of said times in order to obtain a control quantity (S, S') output at a first of said times expected amount of control, and - said at least one control variable elicitor ( 16 , 20 ) ascertains the predicted control variable after a second of said instants in time but still within the first forecast period ( PH1 to PH5 ) state, the control variable expected for the second of the times is taken into account. 9. by the control method described in claim 8, It is characterized in that the at least one controlled variable ascertainer ( 16 , 20 ) is designed as a model-predictive regulator. 10. The control method according to any one of the preceding claims, It is characterized in that the first forecast period (PH1 to PH5) is determined in such a way that it extends at least from the state (Z) in which the rolling stock (1) in the upstream plant part (2) is first affected up to all The rolling stock (1) emerges from the rear equipment part (3). 11. The control method according to any one of the preceding claims, It is characterized in that the control device (10) is at least one of the devices (6, 15, 18, 21) that affect the state (Z) of the rolling stock (1) to obtain the corresponding device (6, 15, 18 , 21) in the expected state within the second prediction period, and the control device (10) is output to the corresponding device (6, 15, 18, 21), the expected state of the corresponding device (6, 15, 18, 21) in the second forecast period is taken into account. 12. The control method according to any one of the preceding claims, It is characterized in that, the control quantity obtainer (16, 20) obtains the control quantity (S, S') through the optimization of the objective function, except for at least one section (14) of the rolled piece (1) In addition to the deviation of the predicted state from the corresponding nominal state, the energy consumption of the processing device is also added to the objective function. 13. Computer program having a machine code (12) which can be directly controlled by a control device (10) of a processing plant for a rolling stock (1), especially a strip-shaped rolling stock (1) ), and the machine code is executed by the control device (10) so that the control device (10) executes a control method having all the steps of the control method according to any one of the preceding claims. 14. The computer program according to claim 13, It is characterized in that the computer program is stored on a data carrier (13) in a machine-readable form. 15. A control device for a processing plant for a rolling stock (1), in particular a strip-shaped rolling stock (1), characterized in that the control device is designed such that during operation it executes a function according to claims 1 to 12 A control method for all steps of any one of the control methods.

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