CN110385344B - Method and device for controlling self-adaptive loop amount of loop of hot continuous rolling mill - Google Patents
Method and device for controlling self-adaptive loop amount of loop of hot continuous rolling mill Download PDFInfo
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- CN110385344B CN110385344B CN201910681846.9A CN201910681846A CN110385344B CN 110385344 B CN110385344 B CN 110385344B CN 201910681846 A CN201910681846 A CN 201910681846A CN 110385344 B CN110385344 B CN 110385344B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/48—Tension control; Compression control
- B21B37/50—Tension control; Compression control by looper control
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
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Abstract
The embodiment of the invention provides a method and a device for controlling the self-adaptive loop amount of a loop of a hot continuous rolling mill, wherein the method comprises the following steps: acquiring a preset sleeve amount corresponding to a target loop of the hot continuous rolling mill; acquiring a first actual sleeve amount of the target loop generated in the process of biting the steel at the head of the strip steel and a second actual sleeve amount of the target loop in the process of rolling the strip steel body; according to the deviation between the preset sleeve amount and the first actual sleeve amount, a sleeve amount adjusting value during strip steel threading is obtained; according to the deviation between the preset sleeve amount and the second actual sleeve amount, obtaining improved parameters when the strip steel body is rolled; and adjusting the set quantity control parameters of the hot continuous rolling mill during threading of the strip steel and rolling of the strip steel body respectively according to the set quantity adjustment value and the improvement parameters. The invention avoids the problem of misadjustment when the head strip steel and the strip steel body are rolled through the sectional adjustment of the loop, obviously improves the accurate control of the loop quantity and avoids the great fluctuation of the loop.
Description
Technical Field
The invention relates to the technical field of steel rolling, in particular to a method and a device for controlling a loop self-adaptive loop amount of a hot continuous rolling mill.
Background
In the hot continuous rolling process, the loop device is important equipment for ensuring the rolling stability and the dimensional precision of the strip steel. Therefore, constant loop amount and micro-tension rolling are the basic characteristics of hot continuous rolling. With the continuous improvement of equipment level and rolling process, the large production of hot-rolled thin specification, limit specification and high-strength steel puts forward more strict requirements on the accurate control of loop amount and rolled piece tension.
The purpose of loop control is to maintain equal second flow between frames. In the actual rolling process, the change of process parameters (such as roll gap fluctuation, incoming material temperature, interference of other control systems and the like) can damage the constant flow per second between the stands, so that the actual sleeve quantity of the loop generates larger deviation. Therefore, the loop quantity needs to be continuously adjusted, but the problem of overshoot or insufficiency easily occurs during adjustment of the loop at present, and in the process of threading the head or dropping the loop at the tail, if the loop quantity is too large or too small, the loop is raised too high or too low, steel drawing or steel stacking accidents can be caused seriously, and the rolling stability is influenced. When the strip steel is rolled in the body, if a large sleeve quantity deviation occurs, the loop can shake violently, so that the outlet thickness of the rolling mill fluctuates, and the basic requirements of customers on the size precision of the strip steel are difficult to meet.
Therefore, there is an urgent need for an adjusting method or device that can adjust the loop more accurately, avoid overshoot, and prevent the loop from shaking.
Disclosure of Invention
In view of this, an object of the embodiments of the present invention is to provide a method and an apparatus for controlling a loop adaptive amount of a hot continuous rolling mill, in which the problem of adjustment mismatch between a head strip and a strip body during rolling is avoided by adjusting a loop in sections, so as to significantly improve accurate control of the loop amount and avoid large fluctuation of the loop.
In a first aspect, the present application provides the following technical solutions through an embodiment:
a method for controlling the self-adaptive loop amount of a loop of a hot continuous rolling mill comprises the following steps:
acquiring a preset sleeve amount corresponding to a target loop of a hot continuous rolling mill, wherein the preset sleeve amount is used for rolling strip steel with a specified thickness; acquiring a first actual sleeve amount of the target loop generated in the process of biting the steel at the head of the strip steel and a second actual sleeve amount of the target loop in the process of rolling the strip steel body; according to the deviation between the preset sleeve amount and the first actual sleeve amount, a sleeve amount adjusting value during strip steel threading is obtained; according to the deviation between the preset sleeve amount and the second actual sleeve amount, obtaining improved parameters when the strip steel body is rolled; and adjusting the set quantity control parameters of the hot continuous rolling mill during threading of the strip steel and rolling of the strip steel body respectively according to the set quantity adjustment value and the improvement parameters.
Preferably, the acquiring a first actual sleeve amount generated in the process of biting the steel at the head of the strip steel by the target loop comprises:
acquiring the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop, which are detected by a hot metal detector; and obtaining the first actual loop quantity according to the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop.
Preferably, the obtaining of the set amount adjustment value when the strip steel is threaded according to the deviation between the preset set amount and the first actual set amount includes:
adjusting a preset proportional gain parameter and a preset integral time parameter according to the deviation between the preset sleeve amount and the first actual sleeve amount; and obtaining the sleeve amount adjusting value when the strip steel is threaded according to the adjusted proportional gain parameter and the adjusted integral time parameter.
Preferably, the obtaining of the set quantity adjustment value during threading of the strip steel specifically includes:
according to
Obtaining the set quantity adjusting value when the strip steel is threaded; wherein, Pi,setIs a preset loop amount, P, of the target loopi,calA first actual loop quantity of a target loop, i represents that the ith loop is the target loop, e (x) is the deviation of the preset loop quantity and the first actual loop quantity, m and n are respectively a proportional link coefficient and an integral link coefficient, kp,0Is an initial proportional gain parameter; t isiIs an integration time parameter; t is the sampling time period.
Preferably, the improvement parameters include: an improved proportional gain parameter and an improved integration time parameter; according to the deviation between the preset sleeve amount and the second actual sleeve amount, obtaining improved parameters of the strip steel body during rolling, and the method comprises the following steps:
obtaining actual sleeve quantity deviation percentage according to the deviation between the preset sleeve quantity and the second actual sleeve quantity; obtaining an improved proportional gain parameter of the current sampling time period according to the actual set quantity deviation percentage and the proportional gain parameter of the last sampling time period; obtaining an improved integral time parameter of the current sampling time period according to the actual sleeve quantity deviation percentage and the integral time parameter of the last sampling time period; when the current sampling time period is a first period, the proportional gain parameter of the previous sampling time period is an initial proportional gain parameter, and the integral time parameter of the previous sampling time period is an initial integral time parameter.
Preferably, the obtaining of the improved proportional gain parameter of the current sampling time period according to the actual set quantity deviation percentage and the proportional gain parameter of the previous sampling time period includes:
based on kp(ep(t))＝(ap+bp(1-sech(cpep(t))))kP,n-1Obtaining an improved proportional gain parameter of the current sampling time period; wherein k isp(ep(t)) is a modified proportional gain parameter for the current sample time period, ap、bp、cpAs a coefficient of the adaptive algorithm, ep(t) is the actual sleeve deflection percentage, kp,n-1Is the proportional gain parameter of the last sampling time period, t is the sampling time period, n represents the nth period, and n-1 is greater than or equal to 0.
Preferably, the obtaining of the improved integration time parameter of the current sampling time period according to the actual set quantity deviation percentage and the integration time parameter of the last sampling time period includes:
based on Ti(ep(t))＝aTsech(cTep(t))Ti,n-1Obtaining an improved integral time parameter of the current sampling time period; wherein, Ti(ep(t)) an integration time parameter that is an improvement of the current sampling time period of the target loop, ep(t) is the percent deviation of the actual sleeve amount, aT、cTBeing coefficients of an adaptive algorithm, Ti,n-1Last sampling time for target loopAnd (3) a period improved integration time parameter, i represents that the ith loop is a target loop, t represents a sampling time period, n represents the nth period, and n-1 is greater than or equal to 0.
In a second aspect, based on the same inventive concept, the present application provides the following technical solutions through an embodiment:
a control device for loop self-adaptive loop quantity of a hot continuous rolling mill comprises:
the device comprises a preset sleeve quantity acquisition module, a preset sleeve quantity control module and a control module, wherein the preset sleeve quantity acquisition module is used for acquiring a preset sleeve quantity corresponding to a target loop of the hot continuous rolling mill, and the preset sleeve quantity is used for rolling strip steel with a specified thickness; the actual loop quantity acquisition module is used for acquiring a first actual loop quantity generated by the target loop in the process of biting the steel at the head of the strip steel and a second actual loop quantity of the target loop in the process of rolling the strip steel body; the first parameter acquisition module is used for acquiring a sleeve amount adjustment value when the strip steel is threaded according to the deviation between the preset sleeve amount and the first actual sleeve amount; the second parameter acquisition module is used for acquiring improved parameters during rolling of the strip steel body according to the deviation between the preset sleeve amount and the second actual sleeve amount; and the adjusting module is used for adjusting the sleeve quantity control parameters of the hot continuous rolling mill during threading of the strip steel and rolling of the strip steel body respectively according to the sleeve quantity adjusting value and the improvement parameters.
Preferably, the actual set quantity obtaining module is further configured to:
acquiring the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop, which are detected by a hot metal detector; and obtaining the first actual loop quantity according to the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop.
Preferably, the first parameter obtaining module is further configured to:
adjusting a preset proportional gain parameter and a preset integral time parameter according to the deviation between the preset sleeve amount and the first actual sleeve amount; and obtaining the sleeve amount adjusting value when the strip steel is threaded according to the adjusted proportional gain parameter and the adjusted integral time parameter.
One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:
the invention provides a method and a device for controlling the loop self-adaptive loop amount of a hot continuous rolling mill, which are used for adjusting the loop amount in real time by respectively adopting the deviation between the first actual loop amount in the rolling process of a strip steel head and the second actual loop amount in the rolling process of a strip steel body and the preset loop amount, thereby realizing quick correction and interference suppression, avoiding the problems of overshoot or insufficient adjustment and the like caused by the fact that the loop is adjusted and not matched with the strip steel head and the strip steel body in the rolling stage according to the same loop scheme.
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is a flow chart of a method for controlling the adaptive loop amount of a hot continuous rolling mill loop according to a first embodiment of the invention;
FIG. 2 is a graph showing the relationship between the proportional gain parameter and the actual percentage of deviation of the jacket volume (the percentage of deviation of the jacket volume) in the first embodiment of the present invention;
FIG. 3 is a graph showing the variation of the integration time parameter with the actual set amount deviation percentage (set amount deviation percentage) in the first embodiment of the present invention;
FIG. 4 is a schematic diagram of a system adjustment loop of the hot continuous rolling mill shown in the first embodiment of the present invention;
fig. 5 is a functional block diagram of a device for controlling the adaptive loop quantity of the loop of the hot continuous rolling mill according to a second embodiment of the invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present invention, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.
First embodiment
Referring to fig. 1, in the present embodiment, a method for controlling a loop adaptive loop amount of a hot continuous rolling mill is provided, and fig. 1 shows a flowchart of the method, where the method includes:
step S10: acquiring a preset sleeve amount corresponding to a target loop of a hot continuous rolling mill, wherein the preset sleeve amount is used for rolling strip steel with a specified thickness;
step S20: acquiring a first actual sleeve amount of the target loop generated in the process of biting the steel at the head of the strip steel and a second actual sleeve amount of the target loop in the process of rolling the strip steel body;
step S30: according to the deviation between the preset sleeve amount and the first actual sleeve amount, a sleeve amount adjusting value during strip steel threading is obtained;
step S40: according to the deviation between the preset sleeve amount and the second actual sleeve amount, obtaining improved parameters when the strip steel body is rolled;
step S50: and adjusting the set quantity control parameters of the hot continuous rolling mill during threading of the strip steel and rolling of the strip steel body respectively according to the set quantity adjustment value and the improvement parameters.
In the embodiment, through steps S10-S50, in the actual rolling process, the deviation between the first actual sleeve amount in the strip head rolling process and the second actual sleeve amount in the strip body rolling process and the preset sleeve amount is respectively adopted to adjust the sleeve amount in real time, so that the rapid correction and the interference suppression are realized, and the problem that the strip rolling stage is not matched due to the adjustment of the loop according to the same scheme, such as the problems of overshoot or insufficient adjustment, can be avoided.
Step S10: and acquiring a preset sleeve amount corresponding to a target loop of the hot continuous rolling mill, wherein the preset sleeve amount is used for rolling the strip steel with the specified thickness.
Before step S10, a layer table of the thickness of the rolled strip and the loop amount may be established for the finish rolling secondary model corresponding to the hot continuous rolling mill. Specifically, the steel strip can be divided according to the specified thickness of the steel strip to be rolled. The loop quantity values of the loops of the band steel with the corresponding layers and the corresponding specified thickness are obtained from the loop quantity layer table, so that the problem that the adjustment capacity of the loops is not matched (exceeds the adjustment range of the loops) due to a single coefficient can be solved. For example, the preset loop amount of each loop of the hot continuous rolling mill can be divided into 5 layers, and stored in the loop amount layer table. Then, in step S10, the sleeve quantity value P of each loop (including the target loop) in the corresponding layer can be obtained from the sleeve quantity layer table according to the size of the specified thicknessi,set。
Step S20: and acquiring a first actual sleeve amount of the target loop generated in the process of biting the steel at the head of the strip steel and a second actual sleeve amount of the target loop in the process of rolling the strip steel body.
In step S20, a first actual jacket amount generated by the target live jacket during the steel biting process at the strip steel head is obtained, and the specific implementation manner includes:
and acquiring the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop, which are detected by a hot metal detector. And then, acquiring the first actual sleeve quantity according to the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop, and ensuring the acquisition accuracy and timeliness of the actual sleeve quantity.
Specifically, it can be expressed as: pi,cal＝k·Δnd·vin·tifWherein i represents that the ith loop is a target loop, and k is a correction coefficient; Δ ndThe main transmission speed of the rolling mill corresponding to the target loop is r/min; v. ofinThe inlet speed of the rolling mill corresponding to the target loop is m/min; t is tifThe recovery time of the dynamic quick drop of the target loop is obtained.
In step S20, a second actual sleeve quantity for the target loop may be obtained by an angle detector provided by the rolling control system via a function converter.
Step S30: and obtaining a sleeve amount adjusting value when the strip steel is threaded according to the deviation between the preset sleeve amount and the first actual sleeve amount.
In step S30, the method specifically includes the following steps:
1. and adjusting a preset proportional gain parameter and a preset integral time parameter according to the deviation between the preset sleeve amount and the first actual sleeve amount.
For example, when the deviation between the preset set quantity and the first actual set quantity is small, the proportional gain parameter can be reduced, and the integral time parameter can be increased; when the deviation between the preset sleeve amount and the first actual sleeve amount is larger, the proportional gain parameter can be increased, and the integral time parameter is reduced; therefore, the quick and accurate adjustment of the steel sleeve amount of the head can be ensured.
2. And obtaining the sleeve amount adjusting value when the strip steel is threaded according to the adjusted proportional gain parameter and the adjusted integral time parameter.
In particular, can be based on
Obtaining the set quantity adjusting value when the strip steel is threaded; wherein, Pi,setIs a preset loop quantity, P, of the ith target loopi,calA first actual sleeve quantity of the ith target loop, e (x) a deviation between the preset sleeve quantity and the first actual sleeve quantity, m and n are respectively a proportional link coefficient and an integral link coefficient (m and n are empirical coefficients, and the specific range can be 0.5-0.9), and kp,0Is an initial proportional gain parameter; t isiIs an integration time parameter; t is the sampling time period.
The accuracy of adjusting the head of the strip steel can be guaranteed through the above formula, and the adjusting formula is set based on the deviation between the preset sleeve amount and the first actual sleeve amount, so that the overshoot problem is avoided while the accurate adjustment is guaranteed, and the loop lifting stability is improved.
Step S40: and obtaining improved parameters during the rolling of the strip steel body according to the deviation between the preset sleeve amount and the second actual sleeve amount.
In step S40, the improvement parameters specifically include: an improved proportional gain parameter and an improved integration time parameter.
Wherein, obtain according to the deviation of presetting a set volume and the actual cover volume of second, obtain the improved proportion gain parameter when belted steel body is rolled, can specifically include:
1. obtaining actual sleeve quantity deviation percentage according to the deviation between the preset sleeve quantity and the second actual sleeve quantity; specifically, it can be expressed as: e.g. of the typep(t)＝(Pi,act-Pi,set)/Pi,setWherein e isp(t) is the percent deviation of the actual sleeve quantity, Pi,actThe second actual loop quantity of the target loop collected by the system in the rolling process of the strip steel body.
2. And obtaining the improved proportional gain parameter of the current sampling time period according to the actual sleeve quantity deviation percentage and the proportional gain parameter of the last sampling time period.
Referring to fig. 2, fig. 2 shows the variation relationship between the proportional gain parameter and the actual sleeve deviation percentage (sleeve deviation percentage), specifically:
based on kp(ep(t))＝(ap+bp(1-sech(cpep(t))))kP,n-1Obtaining an improved proportional gain parameter of the current sampling time period; wherein k isp(ep(t)) is a modified proportional gain parameter for the current sample time period, ap、bp、cpAs a coefficient of the adaptive algorithm, ep(t) is the actual sleeve deflection percentage, kp,n-1Is the proportional gain parameter of the last sampling time period, t is the sampling time period, n represents the nth period, and n-1 is greater than or equal to 0.
3. And obtaining an improved integral time parameter of the current sampling time period according to the actual sleeve quantity deviation percentage and the integral time parameter of the last sampling time period.
Referring to fig. 3, fig. 3 shows the variation relationship between the integration time parameter and the actual sleeve amount deviation percentage (sleeve amount deviation percentage), specifically:
based on Ti(ep(t))＝aTsech(cTep(t))Ti,n-1Obtaining an improved integral time parameter of the current sampling time period; wherein, Ti(ep(t)) an improved integration time parameter for the current sample time period of the ith target loop, ep(t) is the percent deviation of the actual sleeve amount, aT、cTBeing coefficients of an adaptive algorithm, Ti,n-1And (3) an integration time parameter improved for the last sampling time period of the ith target loop, wherein t is the sampling time period, n represents the nth period, and n-1 is greater than or equal to 0.
When the current sampling time period is a first period, the proportional gain parameter of the previous sampling time period is an initial proportional gain parameter, and the integral time parameter of the previous sampling time period is an initial integral time parameter kp,0。
By the above process, the proportional gain parameter and the integral time parameter can be adaptively adjusted between each continuous period based on the deviation percentage of the set quantity. The gain of the sleeve quantity controller is automatically adjusted according to the sleeve quantity deviation percentage without resetting parameters when the strip steel body is rolled; the loop system can be prevented from vibrating, overshoot of loop control is effectively avoided, and rolling stability is improved.
Step S50: and adjusting the set quantity control parameters of the hot continuous rolling mill during threading of the strip steel and rolling of the strip steel body respectively according to the set quantity adjustment value and the improvement parameters.
In step S50, specifically, the set quantity control parameter of the hot continuous rolling mill may be adjusted when rolling the head strip steel during threading of the strip steel based on the set quantity adjustment value; based on the improved parameters (the improved proportional gain parameter and the improved integral time parameter), the control parameter of the sleeve amount of the hot continuous rolling mill is adjusted during rolling of the strip steel body, and the specific adjustment process can be understood with reference to fig. 4, wherein fig. 4 shows a schematic diagram of a system adjustment loop of the hot continuous rolling mill, and details are not repeated.
The invention realizes the sectional adjustment, avoids the problem of overshoot caused by the mismatching of the same adjustment scheme used for rolling the head part or the body part of the strip steel, realizes the requirements of quick correction and interference suppression on two characteristics, can obviously improve the accurate control of the loop quantity and avoids the great fluctuation of the loop. The hot rolling thin specification, the limit specification and the stable batch production of high-strength steel are guaranteed, and the control precision of the strip steel size is improved.
The present invention is described below by way of specific examples.
A loop control system of a hot rolling production line of a certain company is a part of a hot continuous rolling mill control system, a TDC high-speed controller based on industrial process automation of Siemens is adopted, the TDC is configured by using a Simatic (Siemens automation line product) automation system tool, and the CFC (continuous function chart) can be conveniently used for programming.
The finishing mill group of the hot rolling production line is provided with six racks, and five loops are arranged between the racks. In the rolling process, the set sleeve quantity is the premise of the whole control, and the set better sleeve quantity layer table can improve the rolling stability. According to the principle of dividing the layers with the specified thickness of the strip steel, a loop quantity layer table is designed, and 5 layers are divided. The loop quantity values of the respective loops in the respective levels of the loop quantity level table are shown in table 1.
TABLE 1 looping measurement parameter model table
Wherein, F1-F6 are 6 loops, and h is the designated thickness.
Taking the example of the line pipe steel L555MB-1 with the rolling limit thickness specification (21.5mm), it can be known that: the specification of the pipeline steel corresponds to the layer with the thickness of 12 mm-26 mm in the loop quantity parameter model table, and the preset loop quantity P of each loop can be obtained as shown in the table 1i,set：。
In the process of pulling the loop of the strip steel head through the loop, the actual loop amount of the head is completely generated by dynamic speed reduction. The first actual sleeve amount formed by the loop of each frame in the threading process has various deviations from the preset sleeve amount. Aiming at a sleeve quantity control closed-loop system at the head of the strip steel, a proportional link coefficient m and an integral link coefficient n are respectively 0.83 and 0.8, and an initial proportional gain parameter kp,0At 4.8, the initial integration time parameter Ti,0Is 1600. Therefore, the relation of the closed loop system for controlling the sleeve amount of the head of the strip steel obtained by calculation is as follows:
when the loop control is carried out on the head of the strip steel, the proportion gain is reduced, the integral time is increased, head overshoot caused by dynamic quick drop of the loop is avoided, and the loop lifting stability is improved.
In the rolling process of the strip steel body, the actual sleeve amount Pi,actObtained by angle detector via function converter, and preset amountPi,setAnd obtaining the strip steel from a loop quantity layer table according to the specified thickness of the strip steel. The self-adaptive algorithm of the set quantity control parameter is a function of the deviation percentage of the set quantity, and the specific expression is as follows:
as can be seen from fig. 2 and 3, the self-adaptive algorithm of the set quantity control parameters is adopted for controlling the strip steel body, and the proper set quantity control gain parameters can be automatically adopted according to the set quantity deviation.
Further with reference to table 2:
TABLE 2 corresponding data (part) of the set of quantity adaptive algorithms
As can be seen from table 2: when the sleeve amount deviation is increased, a larger proportional gain parameter and a smaller integral gain parameter are adopted, so that the sleeve amount correction speed of the closed-loop system can be accelerated; when the deviation of the set quantity is small, a small proportional gain parameter and a large integral gain parameter are adopted, so that the occurrence of overshoot can be inhibited, and the stability of a closed-loop system is improved. Thereby meeting the requirements of the system on the characteristics of quick correction and interference suppression.
Finally, corresponding functions can be added into the loop control system by using the CFC programming language. By analyzing the process curve of strip steel rolling, the method can basically eliminate the violent shaking of the loop, obviously reduce the thickness fluctuation, simultaneously improve the thickness control precision and powerfully ensure the stable batch production of thin specifications, limit specifications and high-strength steel.
In summary, the method and the device for controlling the loop adaptive amount of the hot continuous rolling mill provided by the invention respectively adopt the deviation between the first actual loop amount in the rolling process of the head of the strip steel and the second actual loop amount in the rolling process of the strip steel body and the preset loop amount to adjust the loop amount in real time, thereby realizing quick correction and interference suppression, avoiding the problems of overshoot or insufficient adjustment and the like caused by the mismatching of the adjustment of the loop on the rolling stage of the head of the strip steel and the rolling stage of the strip steel body according to the same scheme.
Second embodiment
Referring to fig. 5, the present embodiment provides a device for controlling a loop adaptive loop amount of a hot continuous rolling mill, the device includes:
the preset sleeve quantity obtaining module 301 is used for obtaining a preset sleeve quantity corresponding to a target loop of the hot continuous rolling mill, and the preset sleeve quantity is used for rolling strip steel with a specified thickness;
an actual loop quantity obtaining module 302, configured to obtain a first actual loop quantity generated by the target loop in the process of biting steel at the head of the strip steel, and a second actual loop quantity of the target loop in the process of rolling the strip steel body;
a first parameter obtaining module 303, configured to obtain a sleeve amount adjustment value when the strip steel is threaded according to a deviation between the preset sleeve amount and the first actual sleeve amount;
a second parameter obtaining module 304, configured to obtain an improved parameter during rolling of the strip steel body according to a deviation between the preset sleeve amount and the second actual sleeve amount;
and the adjusting module 305 is configured to adjust the set quantity control parameters of the hot continuous rolling mill during threading of the strip steel and rolling of the strip steel body according to the set quantity adjusting value and the improvement parameters.
As an optional implementation manner, the actual set quantity obtaining module 302 is further configured to:
acquiring the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop, which are detected by a hot metal detector; and obtaining the first actual loop quantity according to the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop.
As an optional implementation manner, the first parameter obtaining module 303 is further configured to:
adjusting a preset proportional gain parameter and a preset integral time parameter according to the deviation between the preset sleeve amount and the first actual sleeve amount; and obtaining the sleeve amount adjusting value when the strip steel is threaded according to the adjusted proportional gain parameter and the adjusted integral time parameter.
As an optional implementation manner, the first parameter obtaining module 303 is further configured to:
according to
Obtaining the set quantity adjusting value when the strip steel is threaded; wherein, Pi,setIs a preset loop amount, P, of the target loopi,calA first actual loop quantity of a target loop, i represents that the ith loop is the target loop, e (x) is the deviation of the preset loop quantity and the first actual loop quantity, m and n are respectively a proportional link coefficient and an integral link coefficient, kp,0Is an initial proportional gain parameter; t isiIs an integration time parameter; t is the sampling time period.
As an alternative embodiment, the improvement parameters include: an improved proportional gain parameter and an improved integration time parameter; the second parameter obtaining module 304 is further configured to:
obtaining actual sleeve quantity deviation percentage according to the deviation between the preset sleeve quantity and the second actual sleeve quantity; obtaining an improved proportional gain parameter of the current sampling time period according to the actual set quantity deviation percentage and the proportional gain parameter of the last sampling time period; obtaining an improved integral time parameter of the current sampling time period according to the actual sleeve quantity deviation percentage and the integral time parameter of the last sampling time period; when the current sampling time period is a first period, the proportional gain parameter of the previous sampling time period is an initial proportional gain parameter, and the integral time parameter of the previous sampling time period is an initial integral time parameter.
As an optional implementation manner, the second parameter obtaining module 304 is further configured to:
based on kp(ep(t))＝(ap+bp(1-sech(cpep(t))))kP,n-1Obtaining an improved proportional gain parameter of the current sampling time period; wherein k isp(ep(t)) is a modified proportional gain parameter for the current sample time period, ap、bp、cpAs a coefficient of the adaptive algorithm, ep(t) is the actual sleeve deflection percentage, kp,n- 1Is the proportional gain parameter of the last sampling time period, t is the sampling time period, n represents the nth period, and n-1 is greater than or equal to 0.
As an optional implementation manner, the second parameter obtaining module 304 is further configured to:
based on Ti(ep(t))＝aTsech(cTep(t))Ti,n-1Obtaining an improved integral time parameter of the current sampling time period; wherein, Ti(ep(t)) an integration time parameter that is an improvement of the current sampling time period of the target loop, ep(t) is the percent deviation of the actual sleeve amount, aT、cTBeing coefficients of an adaptive algorithm, T i,n-1 is an improved integral time parameter of a last sampling time period of the target loop, i represents that the ith loop is the target loop, t is the sampling time period, n represents the nth period, and n-1 is more than or equal to 0.
The specific manner in which the respective modules perform the operations and the advantageous effects of the responses have been described in detail in relation to the embodiments of the method, and will not be elaborated upon here.
In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method can be implemented in other ways. The apparatus embodiments described above are merely illustrative, and for example, the flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
In addition, the functional modules in the embodiments of the present invention may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.
The method functions of the present invention may be stored in a computer-readable storage medium if they are implemented in the form of software function modules and sold or used as independent products. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes. It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (5)
1. A method for controlling the self-adaptive loop amount of a loop of a hot continuous rolling mill is characterized by comprising the following steps:
acquiring a preset sleeve amount corresponding to a target loop of a hot continuous rolling mill, wherein the preset sleeve amount is used for rolling strip steel with a specified thickness;
acquiring a first actual sleeve amount of the target loop generated in the process of biting the steel at the head of the strip steel and a second actual sleeve amount of the target loop in the process of rolling the strip steel body;
according to the deviation between the preset sleeve amount and the first actual sleeve amount, a sleeve amount adjusting value during strip steel threading is obtained; the method specifically comprises the following steps: adjusting a preset proportional gain parameter and a preset integral time parameter according to the deviation between the preset sleeve amount and the first actual sleeve amount; obtaining the set quantity adjusting value when the strip steel is threaded according to the adjusted proportional gain parameter and the adjusted integral time parameter;
according to the deviation between the preset sleeve amount and the second actual sleeve amount, obtaining improved parameters when the strip steel body is rolled; the improvement parameters include: an improved proportional gain parameter and an improved integration time parameter; the method comprises the following steps: obtaining actual sleeve quantity deviation percentage according to the deviation between the preset sleeve quantity and the second actual sleeve quantity; obtaining an improved proportional gain parameter of the current sampling time period according to the actual set quantity deviation percentage and the proportional gain parameter of the last sampling time period; obtaining an improved integral time parameter of the current sampling time period according to the actual sleeve quantity deviation percentage and the integral time parameter of the last sampling time period; when the current sampling time period is a first period, the proportional gain parameter of the previous sampling time period is an initial proportional gain parameter, and the integral time parameter of the previous sampling time period is an initial integral time parameter;
the obtaining of the actual sleeve quantity deviation percentage comprises the following steps: based on ep(t)＝(Pi,act-Pi,set)/Pi,setObtaining the actual sleeve quantity deviation percentage; wherein e isp(t) is the percent deviation of the actual sleeve quantity, Pi,actThe second actual loop quantity of the target loop collected by the system in the rolling process of the strip steel body;
obtaining an improved proportional gain parameter for a current sampling time period, comprising: base ofAt kp(ep(t))＝(ap+bp(1-sech(cpep(t))))kP,n-1Obtaining an improved proportional gain parameter of the current sampling time period; wherein k isp(ep(t)) is a modified proportional gain parameter for the current sample time period, ap、bp、cpAs a coefficient of the adaptive algorithm, ep(t) is the actual sleeve deflection percentage, kp,n-1Is a proportional gain parameter of a last sampling time period, t is the sampling time period, n represents the nth period, and n-1 is more than or equal to 0;
obtaining an improved integration time parameter for a current sampling time period, comprising:
based on Ti(ep(t))＝aTsech(cTep(t))Ti,n-1Obtaining an improved integral time parameter of the current sampling time period; wherein, Ti(ep(t)) an integration time parameter that is an improvement of the current sampling time period of the target loop, ep(t) is the percent deviation of the actual sleeve amount, aT、cTBeing coefficients of an adaptive algorithm, Ti,n-1An improved integral time parameter for the last sampling time period of the target loop, wherein i represents that the ith loop is the target loop, t is the sampling time period, n represents the nth period, and n-1 is more than or equal to 0;
and adjusting the set quantity control parameters of the hot continuous rolling mill during threading of the strip steel and rolling of the strip steel body respectively according to the set quantity adjustment value and the improvement parameters.
2. The method of claim 1, wherein the obtaining of the first actual sleeve amount generated in the process of biting the steel head of the target loop comprises:
acquiring the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop, which are detected by a hot metal detector;
and obtaining the first actual loop quantity according to the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop.
3. The method according to claim 1, wherein the obtaining of the set quantity adjustment value during threading of the strip steel specifically comprises:
according to
Obtaining the set quantity adjusting value when the strip steel is threaded;
wherein, Pi,setIs a preset loop amount, P, of the target loopi,calA first actual loop quantity of a target loop, i represents that the ith loop is the target loop, e (x) is the deviation of the preset loop quantity and the first actual loop quantity, m and n are respectively a proportional link coefficient and an integral link coefficient, kp,0Is an initial proportional gain parameter; t isiIs an integration time parameter; t is the sampling time period.
4. A control device for loop self-adaptive loop quantity of a hot continuous rolling mill is characterized by comprising:
the device comprises a preset sleeve quantity acquisition module, a preset sleeve quantity control module and a control module, wherein the preset sleeve quantity acquisition module is used for acquiring a preset sleeve quantity corresponding to a target loop of the hot continuous rolling mill, and the preset sleeve quantity is used for rolling strip steel with a specified thickness;
the actual loop quantity acquisition module is used for acquiring a first actual loop quantity generated by the target loop in the process of biting the steel at the head of the strip steel and a second actual loop quantity of the target loop in the process of rolling the strip steel body;
the first parameter acquisition module is used for acquiring a sleeve amount adjustment value when the strip steel is threaded according to the deviation between the preset sleeve amount and the first actual sleeve amount; the method specifically comprises the following steps: adjusting a preset proportional gain parameter and a preset integral time parameter according to the deviation between the preset sleeve amount and the first actual sleeve amount; obtaining the set quantity adjusting value when the strip steel is threaded according to the adjusted proportional gain parameter and the adjusted integral time parameter;
a second parameter obtaining module forAccording to the deviation between the preset sleeve amount and the second actual sleeve amount, obtaining improved parameters when the strip steel body is rolled; the improvement parameters include: an improved proportional gain parameter and an improved integration time parameter; and is also used for: obtaining actual sleeve quantity deviation percentage according to the deviation between the preset sleeve quantity and the second actual sleeve quantity; obtaining an improved proportional gain parameter of the current sampling time period according to the actual set quantity deviation percentage and the proportional gain parameter of the last sampling time period; obtaining an improved integral time parameter of the current sampling time period according to the actual sleeve quantity deviation percentage and the integral time parameter of the last sampling time period; when the current sampling time period is a first period, the proportional gain parameter of the previous sampling time period is an initial proportional gain parameter, and the integral time parameter of the previous sampling time period is an initial integral time parameter; and is also used for: based on ep(t)＝(Pi,act-Pi,set)/Pi,setObtaining the actual sleeve quantity deviation percentage; wherein e isp(t) is the percent deviation of the actual sleeve quantity, Pi,actThe second actual loop quantity of the target loop collected by the system in the rolling process of the strip steel body; obtaining an improved proportional gain parameter for a current sampling time period, comprising: based on kp(ep(t))＝(ap+bp(1-sech(cpep(t))))kP,n-1Obtaining an improved proportional gain parameter of the current sampling time period; wherein k isp(ep(t)) is a modified proportional gain parameter for the current sample time period, ap、bp、cpAs a coefficient of the adaptive algorithm, ep(t) is the actual sleeve deflection percentage, kp,n-1Is a proportional gain parameter of a last sampling time period, t is the sampling time period, n represents the nth period, and n-1 is more than or equal to 0; and is also used for: based on Ti(ep(t))＝aTsech(cTep(t))Ti,n-1Obtaining an improved integral time parameter of the current sampling time period; wherein, Ti(ep(t)) an integration time parameter that is an improvement of the current sampling time period of the target loop, ep(t) is truePercent deviation of the amount of the boundary sleeve, aT、cTBeing coefficients of an adaptive algorithm, Ti,n-1An improved integral time parameter for the last sampling time period of the target loop, wherein i represents that the ith loop is the target loop, t is the sampling time period, n represents the nth period, and n-1 is more than or equal to 0;
and the adjusting module is used for adjusting the sleeve quantity control parameters of the hot continuous rolling mill during threading of the strip steel and rolling of the strip steel body respectively according to the sleeve quantity adjusting value and the improvement parameters.
5. The apparatus of claim 4, wherein the actual jacket amount obtaining module is further configured to:
acquiring the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop, which are detected by a hot metal detector;
and obtaining the first actual loop quantity according to the actual speed of the strip steel, the main transmission speed corresponding to the target loop, the inlet speed corresponding to the target loop and the dynamic speed reduction recovery time of the target loop.
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| JP3567836B2 (en) * | 1999-12-24 | 2004-09-22 | Ｊｆｅスチール株式会社 | Looper control method between stands of continuous rolling mill |
| CN101219438B (en) * | 2008-01-25 | 2011-05-18 | 广州珠江钢铁有限责任公司 | Hot continuous rolling mill loop control method and used controller |
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