CN115261600A - Artificial intelligence automatic control method for annealing furnace tension - Google Patents
Artificial intelligence automatic control method for annealing furnace tension Download PDFInfo
- Publication number
- CN115261600A CN115261600A CN202110483149.XA CN202110483149A CN115261600A CN 115261600 A CN115261600 A CN 115261600A CN 202110483149 A CN202110483149 A CN 202110483149A CN 115261600 A CN115261600 A CN 115261600A
- Authority
- CN
- China
- Prior art keywords
- tension
- furnace
- rollers
- strip steel
- roller
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D11/00—Process control or regulation for heat treatments
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/26—Methods of annealing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
- C21D8/1216—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the working step(s) being of interest
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Electromagnetism (AREA)
- Manufacturing & Machinery (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Abstract
An artificial intelligent automatic control method for the tension of an annealing furnace comprises three steps of an inter-roller tension control model, an in-furnace equal tension distribution model and a genetic algorithm tension control logic, wherein the three steps are used for carrying out motion control on furnace rollers of the annealing furnace according to an inter-roller tension value, outputting an inter-roller tension target value accurately, controlling the in-furnace tension distribution according to the equal tension model, and finally carrying out intelligent iteration through the genetic algorithm to carry out tension control, so that the control precision is improved. According to the invention, when the secondary annealing product of the non-oriented silicon steel production line is produced, the annealing furnace is continuously and stably operated through the plate by the designed tension control artificial intelligence control method, the distribution uniformity of the tension in the furnace is improved, the control stability, the control precision and the size distribution precision of the tension in the furnace are improved, the magnetic performance of the actual finished product is improved and is close to the upper limit of the quality standard of the brand, the product performance is improved, and the profit margin of the product is increased.
Description
Technical Field
The invention relates to the field of metal metallurgy automation, in particular to an automatic control method for the annealing furnace tension, which takes an inter-roller tension model and a mathematical model of the in-furnace equal tension as control theoretical bases and is assisted by artificial intelligence.
Background
At present, in the tension control research of silicon steel production lines of various metal metallurgy enterprises, a tension control mode is often used, the tension control mode is a dynamic compensation mode based on PI proportional-integral control, and the tension control is taken as the key for stable operation of a continuous annealing line, so that the silicon steel products fully eliminate rolling stress in an annealing furnace, the mechanical property is improved, the strip shape quality of strip steel is ensured, and the tension control of a non-oriented silicon steel production line can meet the process setting precision of products of various specifications and models.
In the tension control mode in the prior art, the tension control output is increased when the detected tension value is smaller than the set value, and the tension value under the actual condition is larger than the set value due to the response speed of the system, and the tension output is reduced by the control system at the moment, so that the tension values at the inlet and the outlet of the annealing furnace are continuously adjusted in a repeated mode.
Although the tension control method in the prior art is simple and effective, the method has the obvious defects that a stable tension value cannot be formed and maintained all the time, and because only the total tension value of the inlet and the outlet of the annealing furnace can be controlled, an effective automatic control means is lacked for the magnitude and the distribution of the tension value of the strip steel in the annealing furnace.
In addition, when non-oriented silicon steel products such as Toyota material and the like are produced by the tension control mode in the prior art, the tension control mode has a special process of secondary rolling, so that the tension in the furnace is uncontrollable and randomly distributed, the phenomenon of strip steel deviation is very easy to occur, and the production continuity and the product quality are seriously influenced.
In addition, researches show that the control precision of the annealing tension of the non-oriented silicon steel is improved, the distribution and the crystal size of silicon crystals can be effectively controlled, and the magnetic induction strength is improved, which mainly comprises the following steps:
(1) The non-oriented silicon steel cold-rolled steel strip is crystallized by an annealing process, the grain size changes along with the annealing tension, the grain size is uniform when the stress is 4 MPa, and the average diameter reaches the maximum value; when the annealing tension is changed, the recrystallized grain size and distribution are deteriorated;
(2) In the annealing and crystallization process of the non-oriented silicon steel cold rolled steel strip, the annealed silicon steel plate with the stress of 4 MPa has the quality characteristics of high magnetic induction and low iron loss.
Through the research, the improvement of magnetic induction intensity and the reduction of iron loss can promote the electromagnetic properties of rotating electrical machines in each control area:
(1) In a high-rotation-speed flux weakening control and low-rotation-speed constant-torque control area, the output torque of the motor can be improved by increasing the air gap flux;
(2) In a high-rotating-speed weak-magnetic control and low-rotating-speed constant-torque control area, the increase of the magnetic induction intensity can reduce the phase current of the motor and improve the capacity of converting unit current into torque;
(3) The improvement of the magnetic induction intensity can optimize the inductance value of the motor, reduce the motor pulsation torque and enable the current of the motor in the low-rotating-speed constant-torque control area to be more stable;
(4) The reduction of the iron loss of the non-oriented silicon steel strip can reduce the total iron loss of the motor after the tabletting and packaging, and obviously improves the electromagnetic conversion efficiency of the motor in a high-speed rotating area of the motor.
Therefore, the important parameter for measuring the quality standard of the non-oriented silicon steel is magnetic induction strength, and the magnetic induction strength has a direct relation with the stability and the precision of the tension control of the annealing furnace. With the successive development of various high-performance and high-grade silicon steel products, higher requirements are put forward on the production process and the control precision. The strip steel is heated and cooled in an annealing furnace, and tension control is a precondition for stable and continuous production of the strip steel. The improvement of the tension control precision is also the guarantee of the quality of the strip steel. The high-grade silicon steel product has higher silicon content, the brittleness of a steel strip is increased, and the tension control of an annealing furnace directly influences the continuity of production and the product quality while the thickness specification is reduced; the special secondary rolling process of the Toyota material non-oriented silicon steel increases the difficulty of tension control. The tension is not only related to the magnetic properties of the silicon steel strip but also to the continuity of the production. The traditional control scheme such as PID control has the defects of system oscillation, unsatisfactory steady-state performance and the like, so that tension fluctuation is caused, and the process requirements are difficult to meet.
Through search, patent publication No.: CN 106381379A's an annealing stove internal tension control method and control system provides a mode of switching to tension calculated value compensation control when tension detection device is unusual, has avoided the unit operation trouble. However, this patent only addresses tension control in an abnormal region of the tension meter, and does not describe tension control in the furnace.
Patent publication No.: CN108677002A, a method for controlling tension compensation in a furnace, which is suitable for a continuous rolling horizontal annealing furnace, is characterized in that a bouncing roller device is arranged at the inlet and the outlet of the annealing furnace, and the total tension value at the inlet and the outlet of the annealing furnace is dynamically adjusted through proportional-integral control. However, through practical use, the patent is found to invest a large amount of capital newly added equipment, only aims at tension control of an inlet and an outlet of an annealing furnace, and still has no effective control means for the distribution and the precision of the tension in the furnace.
Patent publication No.: CN103436683A discloses an intelligent control system and method for a continuous annealing furnace, which adds a sensor and other means, adds a function of remotely monitoring the tension and the temperature of the annealing furnace, and relates the temperature variation to the tension control coefficient to adjust the tension in the furnace. However, this patent is directed to a wire product line having a tubular continuous annealing furnace as the main facility, and is distinguished from the annealing furnace to which this application relates, which produces silicon steel strip.
In addition, through international patent search, patent publication No.: KR1020090112943A "A TENSION CONTROL METHOD AND SYSTEM OF A CONTINUOUS ANNEALING FURNACE", which respectively performs optimization CONTROL on the speed AND TENSION OF the transmission roller by adjusting the gains OF proportional AND integral parameters, thereby improving the CONTROL range OF the TENSION in the FURNACE. However, the control mode of the patent still adopts PI control, and a tension controller algorithm is not innovative and is different from the algorithm control of the application.
In summary, besides various defects in the prior art, the patent publications have problems of inapplicability, different production lines, different algorithms and the like, so that a novel automatic control method for the annealing furnace tension is urgently needed, the problems can be effectively solved, meanwhile, the motion control can be performed on the tension value in the annealing furnace, the tension value can be accurately matched with the target value of the tension between the output rollers, the tension control is performed through iteration of a new algorithm, the control precision is improved, and finally, the operation stability of the strip steel in the annealing furnace and the magnetism of the strip steel after annealing are improved.
Disclosure of Invention
In order to solve the problems, the invention provides an artificial intelligence automatic control method for the tension of an annealing furnace, which designs an artificial intelligence tension controller according to the characteristic that continuous steady-state fluctuation of the tension is similar to a unimodal function, uses the theory of automatic iterative optimization of a genetic algorithm for stable output of the tension controller, forms a control model of the tension controller by taking an inter-roller tension model and an in-furnace equal tension model as theoretical bases, can automatically adjust the tension distribution in the furnace by matching with the artificial intelligence tension controller, and has better control precision and effect than the proportional-integral control in the prior art.
The invention relates to an artificial intelligent automatic control method for the tension of an annealing furnace, which comprises the following specific steps:
an artificial intelligent automatic control method for the tension of an annealing furnace comprises three steps of an inter-roller tension control model, an in-furnace equal tension distribution model and a genetic algorithm tension control logic, and specifically comprises the following steps:
1) And (3) calculating an inter-roller tension control model:
the tension model between the rollers in the step 1) takes the tension of the strip steel between the adjacent rollers in the furnace as a research object, and calculates the tension of the strip steel in the furnace, which is as follows:
1.1 According to theoretical mechanics, the tension borne by the strip steel between adjacent furnace rollers in the annealing furnace is analyzed, the stress borne by the solid is in direct proportion to the strain quantity, and the formula is as follows:
σ＝Eε (1-1)
in the formula:
sigma is the stress borne by the strip steel;
epsilon is the strain of the strip steel;
e is a Young modulus ratio coefficient;
1.2 The strain epsilon is equal to the length variation of the strip steel within t time and the length L of the initial moment0The ratio is as follows:
ε＝△L/L0 (1-2)
in the formula:
epsilon is the strain of the strip steel;
delta L is the length variation of the strip steel;
L0the initial length of the strip steel;
1.3 Suppose stress σ between the two rolls0When 0, the initial length of the strip steel between the rolls is L0When the stress change is sigma, the length change of the strip steel is delta L, and the two formulas are combined to deduce:
in the formula:
sigma is the stress on the strip steel;
e is the Young modulus ratio coefficient;
when the delta L is stress sigma, the length change quantity of the strip steel is changed;
L0when the stress between the two rollers is 0, the initial length of the strip steel between the rollers is set;
1.4 Length change amount):
1.5 The tension of the strip steel between the adjacent furnace rollers is related to the initial length of the strip steel between the furnace rollers and the length of the strip steel sent in and out by the adjacent furnace rollers along the running direction of the strip steel, namely related to the speed difference;
continuously converting the length of the strip steel between the rollers, and the initial length L of the strip steel between two adjacent rollers0Comprises the following steps:
in the formula:
L0when the stress between the two rollers is 0, the initial length of the strip steel between the rollers is determined;
l is the length of stress sigma time borne by the strip steel between the rollers;
sigma is the stress borne by the strip steel;
e is the Young modulus ratio coefficient;
1.6 For the nth and the (n-1) th furnace rollers along the running direction of the strip steel, the initial distance and the stress are as follows:
in the formula:
Ln0the length of the strip steel between the nth furnace roller and the (n-1) th furnace roller is not influenced by external force;
Lnthe strip steel between the two rollers is stressed by a stress of sigmanThe length of time;
1.7 Steel strip stress σ between adjacent furnace rollsnIt should be:
1.8 Derived from both sides of the above equation:
in the formula:
dσnthe variable quantity of the stress borne by the strip steel between the nth furnace roller and the (n-1) th furnace roller is obtained;
Lnthe strip steel between the two rolls is stressed by a stress of sigmanThe length of time;
dLnthe length variation of the outlet of the nth furnace roller is obtained;
dLn-1the length variable quantity of the inlet of the nth furnace roller is obtained;
σnnamely the stress borne by the strip steel between the outlet rollers of the nth furnace roller;
σn-1namely the stress borne by the strip steel between the inlet rollers of the nth furnace roller;
e is a Young modulus ratio coefficient;
1.9 The above-mentioned formulas (1-8) reflect the amount of change σ in stress between adjacent rollsnThe length variation dL of the strip steel entering and exiting from the rollern、dLn-1In relation to this, when the furnace roller n is at a linear velocity vnAt run-time, within unit time dt:
the variation of the outlet length of the nth roll is as follows:
dLn＝vn+1dt；
the variation of the inlet length of the nth roll is as follows:
dLn-1＝vndt；
namely, the above formula (1-8) is modified to:
in the formula:
dσnthe variation of the stress borne by the strip steel between the nth furnace roller and the (n-1) th furnace roller is shown;
Lnthe strip steel between the two rolls is stressed by a stress of sigmanThe length of time;
vnis the n-th roller outlet linear velocity;
vn-1is the nth roller inlet linear velocity;
σnnamely the stress borne by the strip steel between the outlet rollers of the nth furnace roller;
σn-1namely the stress borne by the strip steel between the inlet rollers of the nth furnace roller;
dt is a unit time;
e is the Young modulus ratio coefficient;
1.10 Obtained by further collating the above equations (1-9):
1.11 In the above formula (1-10),
the above equation is simplified as:
1.12 A lagrange transformation is performed on both sides of the above equation (1-11) to obtain:
in the formula:
meaning the length of the strip steel at the outlet of a furnace roller n and the linear velocity v of the rollernThe ratio, i.e. the time consumed t is constant for the greater the rotation speed of the furnace roller nnThe smaller the stress is, the smaller the stress borne by the strip steel at the n outlet of the furnace roller is;
equations (1-12) indicate that: the linear velocity of the nth furnace roller can control the strip steel stress between the rollers of the adjacent furnace rollers, namely the strip steel tension at the outlet of the nth furnace roller is a steady-state function of first-order inertia output when the velocity and the inlet tension of the furnace rollers are known boundary conditions;
1.13 Finally, continuing to derive the above equations (1-12), the general equation for the roll-to-roll tension model between any two rolls is:
in the formula:
Tnthe tension of the intermediate strip steel of the furnace roller n roller is obtained;
Tn-1is the tension of the strip steel between the furnace roller n-1;
e is a Young modulus ratio coefficient;
a is the unit sectional area of the strip steel;
vnis the linear velocity of an outlet of a furnace roller n;
vn-1is the linear velocity of an inlet of a furnace roller n;
the formula (1-13) is a model expression of the tension between the rollers obtained in the step 1), and means the tension T borne by the strip steel between the rollers of the adjacent furnace rollersnIs the difference v between the linear velocities of two rollersn-vn-1Tension T of strip steel between front and rear adjacent furnace rollersn-1The first-order inertia function of the furnace is in direct proportion to the product of the unit sectional area of the strip steel and in inverse proportion to the linear speed of the furnace roller; when the strip steel in the furnace runs at a constant speed, the specification of the strip steel is determined, and the tension between the rollers is unchanged; when the linear velocity of the furnace roller changes, the rotating speed of the furnace roller changes, the larger the rotating speed of the furnace roller is, the longer the length of the conveyed strip steel is, and the smaller the tension force between the rollers is; on the contrary, the rotating speed of the furnace rollers is reduced, the conveying capacity of the strip steel is reduced, and the tension between the rollers is increased;
2) And (3) calculating an in-furnace equal tension distribution model:
the in-furnace equal tension distribution model in the step 2) controls and models the in-furnace tension distribution based on the strip steel tension between the rollers, and the model specifically comprises the following steps:
2.1 According to the principle that the tension of the strip steel in the furnace changes equivalently, combining a tension model between rollers and defining the inlet tension of the annealing furnace as TentThe outlet tension of the annealing furnace is TextWhen the tension is transmitted from the outlet direction to the inlet direction of the annealing furnace, the tension variation of the last furnace roller at the outlet is as follows:
△T＝Text-Tlast (2-1)
in the formula:
Textthe outlet tension of the annealing furnace can be measured by an outlet tension meter of the annealing furnace;
Tlastthe tension between the last furnace roller of the annealing furnace;
delta T is the tension variation between the outlet tension of the annealing furnace and the last furnace roller at the outlet;
2.2 N) tension value variation between furnace rolls:
△Tn＝Tn-Tn-1 (2-2)
in the formula:
Tnis the tension between the furnace roller n;
Tn-1is the tension between the furnace roller n-1;
△Tnis the tension difference between any adjacent rollers;
2.3 Tension transmission and the ideal state of equal tension change, the tension change amount between the first furnace roller at the inlet of the annealing furnace:
△T1＝T2-T1＝T1-Tent (2-3)
in the formula:
T2is the tension between the furnace roller 2;
T1is the tension between the furnace roller 1;
Tentthe annealing furnace inlet tension can be measured by an annealing furnace inlet tensiometer;
△T1the tension difference between the adjacent rollers of the furnace roller 1;
2.4 When the annealing furnace tension is ideally distributed:
because the inlet tension and the outlet tension are equal to each other in actual production, the ideal tension control effect is that the sum of the tension variation in the furnace is 0, namely
Assuming that the tension distribution in the furnace is in an ideal state, the tension in the furnace is changed in an equivalent manner, and the condition of uniform tension distribution between furnace rollers is met, namely the tension variation of the strip steel between adjacent furnace rollers is consistent and is also | [ delta ] T |; annealing stove furnace interior tension changes between adjacent stove roller equivalent, reduces to 0 to the annealing stove middle part, for making zero tension in annealing stove middle part, annealing stove speed is given by annealing stove middle part stove roller as the benchmark, by the annealing stove middle part to both sides generation control tension change's stack velocity to by income, export the tensiometer as tensionThe tension is transmitted to the inside of the annealing furnace according to the standard, the tension variation quantity of the inlet and the outlet of the annealing furnace is equal in magnitude and opposite in direction;
therefore, the furnace equal tension control model is as follows:
designing a new tension control scheme, respectively controlling the tension of an inlet of the annealing furnace and the tension of an outlet of the annealing furnace, and adding an inlet tension controller and an outlet tension controller of the annealing furnace, wherein the inlet tension controller controls a No. 1 roller at the inlet of the annealing furnace to a No. 2 roller in the middle of the annealing furnace (n-1), and the outlet tension controller controls a No. 2 roller in the middle of the annealing furnace to a No. n roller at the outlet of the annealing furnace;
in this step, the input control amount of the tension controller is respectively delta Tent、△TextThe number of furnace rollers in the annealing furnace is n, and n/2 furnace rollers in the middle of the annealing furnace are used as the speed reference of the annealing furnace;
the variable quantity of the tension between the furnace rollers at the inlet section is as follows:
the tension variation between the furnace rollers at the outlet section is as follows:
in the above formulas (2-5), (2-6):
TTM1is an annealing furnace inlet tensiometer measurement;
TTM2is an annealing furnace exit tensiometer measurement;
△Tentthe tension change value between the furnace rollers at the inlet section of the annealing furnace is used, and the furnace rollers output positive torque;
△Textthe tension change value between the furnace rollers at the outlet section of the annealing furnace is used, and the furnace rollers output negative torque;
3) Genetic algorithm tension control logic:
the genetic algorithm tension control logic in the step is based on an artificial intelligence algorithm and combines the characteristics of industrial PLC automatic control logic to realize the tension control of the annealing furnace, and the genetic algorithm tension control logic specifically comprises the following steps:
according to the genetic algorithm operation rule:
GA＝(C,E,P0,M,Φ,Γ,Ψ,T) (3-1)
in the formula: c is a data sorting mode of chromosome individuals, and the data lengths of the chromosome individuals in GA are consistent;
e is a fitness function of the individual;
P0is an initial population;
m is the population data volume;
phi, gamma and psi are respectively a selection operator, a crossover operator and a mutation operator;
t represents an algorithm termination condition, namely iteration times;
the genetic algorithm tension control logic designs tension controller control logic by combining the logic control of industrial PLC according to the genetic algorithm operation rule, and comprises the following steps:
for each furnace roller motor, reading a torque value output by the current motor, writing the torque value into a transmission control background data block, then using a torque variable in a corresponding address as a chromosome parent individual, performing iterative computation of a genetic algorithm, then writing data meeting fitness into data qualification of a child individual, performing cyclic computation, and finally outputting an optimal solution control quantity and then performing tension control;
4) After the steps 1) to 3) are finished, outputting a difference value between the strip steel tension and the tension change between adjacent furnace rollers by a furnace roller motor through adopting the tension control model between the rollers in the step 1) and the tension distribution model in the furnace in the step 2), independently controlling the output of the furnace roller motor, taking a furnace roller theoretical tension value as a control target, inputting the actual furnace roller tension by a tension controller, and finally generating a superposition speed through a speed adapter by using the control quantity of the tension controller after iterative calculation of a genetic algorithm in the genetic algorithm tension control logic in the step 3) to control the tension between the rollers in the furnace.
The artificial intelligence automatic control method of the annealing furnace tension is characterized in that the control scheme of the tension controller in the genetic algorithm tension control logic in the step 4) is as follows:
the strip steel tension of each motor at the moment of a sampling period is read as an individual numerical value in a chromosome, the theoretical value of the tension between rollers is used as the cyclic control of fitness, the final result is converged, the limitation of iteration times is cancelled, the tension control is kept, the optimal solution control quantity after iteration is used as the input of a control variable, the control variable is converted into an additional speed through a speed adapter and is sent to a furnace roller motor inverter unit to realize the tension control, and the tension control effect after the optimization is implemented is verified through the acquisition and comparison of process data.
The design improves the tension control capability of the annealing furnace, and the optimization effect can be verified and implemented through the acquisition and comparison of process data.
The artificial intelligent automatic control method for the annealing furnace tension has the following beneficial effects that:
1. according to the artificial intelligent automatic control method for the tension of the annealing furnace, the output torque direction of the furnace roller before use is negative, the furnace roller is controlled according to the zero tension theory in the furnace after use, the speed of the furnace roller as the annealing furnace is given, the speed is consistent with the control scheme, and the distribution uniformity of the tension in the furnace is improved;
2. according to the artificial intelligent automatic control method for the tension of the annealing furnace, the fluctuation amplitude of the output tension of the furnace roller in sampling time of each section is reduced by about 70% on average after the method is used, and the control stability of the tension in the furnace is improved;
3. the invention relates to an artificial intelligence automatic control method of annealing furnace tension, the annealing furnace tension is transmitted from an outlet tension meter to an inlet before use, the furnace tension is integrally controlled and adjusted, the furnace tension is randomly distributed, the annealing furnace tension is decreased gradually from an inlet and an outlet to the inside of the furnace by the same delta T respectively after use, the annealing furnace tension is reduced to zero tension at a furnace roller in the middle of the annealing furnace, and the furnace tension control precision is improved;
4. according to the artificial intelligent automatic control method for the tension of the annealing furnace, disclosed by the invention, the performance data of different grades of non-oriented silicon steel products are tested through quality inspection after the method is used, the product performance before and after the tension control in the furnace is implemented is compared, the iron loss values of middle and low grades of products are improved, and the magnetic induction intensity of high grades of products is improved; the low-frequency alternating current iron loss value of the middle-grade and low-grade non-oriented silicon steel products is reduced, the peak magnetic induction intensity of the high-grade non-oriented silicon steel products is improved, the magnetic performance of the products with various specifications is close to the upper limit of the quality standard of the corresponding grade, the product performance is improved, and the profit margin of the products is increased.
Drawings
FIG. 1 is a diagram of the genetic algorithm operation rule in step 3) genetic algorithm tension control logic of the artificial intelligence automatic control method for annealing furnace tension of the present invention;
FIG. 2 is a flow chart of the logic for calculating the tension between the rolls in the step 3) genetic algorithm tension control logic of the method for automatically controlling the tension of the annealing furnace according to the artificial intelligence of the invention.
Detailed Description
The method for automatically controlling the tension of the annealing furnace by artificial intelligence is further described by combining the attached drawings and the embodiment.
Examples
An artificial intelligent automatic control method for the tension of an annealing furnace comprises three steps of an inter-roller tension control model, an in-furnace equal tension distribution model and a genetic algorithm tension control logic, and specifically comprises the following steps:
1) Calculation of the inter-roller tension control model:
the tension model between the rollers in the step 1) takes the tension of the strip steel between the adjacent rollers in the furnace as a research object, and calculates the tension of the strip steel in the furnace, which is as follows:
1.1 According to theoretical mechanics, the tension borne by the strip steel between adjacent furnace rollers in the annealing furnace is analyzed, the stress borne by the solid is in direct proportion to the strain quantity, and the formula is as follows:
σ＝Eε (1-1)
in the formula:
sigma is the stress on the strip steel;
epsilon is the strain of the strip steel;
e is the Young modulus ratio coefficient;
1.2 The strain epsilon is equal to the length variation of the strip steel within t time and the length L of the initial moment0The ratio is as follows:
ε＝△L/L0 (1-2)
in the formula:
epsilon is the strain of the strip steel;
delta L is the length variation of the strip steel;
L0the initial length of the strip steel;
1.3 Suppose stress σ between two rolls0When 0, the initial length of the strip steel between the rolls is L0When the stress change is sigma, the length change of the strip steel is delta L, and the two formulas are combined to deduce:
in the formula:
sigma is the stress borne by the strip steel;
e is the Young modulus ratio coefficient;
when the delta L is stress sigma, the length change quantity of the strip steel is changed;
L0when the stress between the two rollers is 0, the initial length of the strip steel between the rollers is determined;
1.4 Length change amount:
1.5 The tension of the strip steel between the adjacent furnace rollers is related to the initial length of the strip steel between the furnace rollers and the length of the strip steel sent into and sent out from the adjacent furnace rollers along the running direction of the strip steel, namely related to the speed difference;
continuously converting the length of the strip steel between the rolls, the initial length L of the strip steel between two adjacent rolls0Comprises the following steps:
in the formula:
L0when the stress between the two rollers is 0, the initial length of the strip steel between the rollers is determined;
l is the length of the stress sigma applied to the strip steel between the rollers;
sigma is the stress on the strip steel;
e is a Young modulus ratio coefficient;
1.6 For the nth and the (n-1) th furnace rollers along the running direction of the strip steel, the initial distance and the stress are as follows:
in the formula:
Ln0the length of the strip steel between the nth furnace roller and the (n-1) th furnace roller is not influenced by external force;
Lnthe strip steel between the two rolls is stressed by a stress of sigmanThe length of time;
1.7 Strip stress sigma between adjacent furnace rollsnIt should be:
1.8 Derived from both sides of the above equation:
in the formula:
dσnthe variation of the stress borne by the strip steel between the nth furnace roller and the (n-1) th furnace roller is shown;
Lnthe strip steel between the two rollers is stressed by a stress of sigmanThe length of time;
dLnthe length variation of the outlet of the nth furnace roller is obtained;
dLn-1the length variation of the inlet of the nth furnace roller is obtained;
σnnamely the stress borne by the strip steel between the outlet rollers of the nth furnace roller;
σn-1namely the stress borne by the strip steel between the inlet rollers of the nth furnace roller;
e is the Young modulus ratio coefficient;
1.9 The above-mentioned formulas (1-8) reflect the amount of change σ in stress between adjacent rollsnThe length variation dL of the strip steel entering and exiting from the rollern、dLn-1In relation to this, when the furnace roller n is at a linear velocity vnIn operation, in unit time dt:
the variation of the outlet length of the nth roll is as follows:
dLn＝vn+1dt；
the variation of the inlet length of the nth roll is as follows:
dLn-1＝vndt；
that is, the above equation (1-8) is modified to:
in the formula:
dσnthe variation of the stress borne by the strip steel between the nth furnace roller and the (n-1) th furnace roller is shown;
Lnthe strip steel between the two rolls is stressed by a stress of sigmanThe length of time;
vnis the nth roller outlet linear velocity;
vn-1is the nth roller inlet linear velocity;
σnnamely the stress borne by the strip steel between the outlet rollers of the nth furnace roller;
σn-1namely the stress borne by the strip steel between the inlet rollers of the nth furnace roller;
dt is a unit time;
e is a Young modulus ratio coefficient;
1.10 Obtained by further working up the above equations (1-9):
1.11 In the above-mentioned formulas (1 to 10),
will be the above formulaThe method is simplified as follows:
1.12 A lagrange transformation is performed on both sides of the above equation (1-11) to obtain:
in the formula:
meaning the length of the strip steel at the outlet of a furnace roller n and the linear velocity v of the rollernThe ratio, i.e. the time consumed by the furnace roller n is constant t for a greater number of revolutionsnThe smaller the stress is, the smaller the stress borne by the strip steel at the n outlet of the furnace roller is;
equations (1-12) show that: the linear velocity of the nth furnace roller can control the strip steel stress between the rollers of the adjacent furnace rollers, namely the strip steel tension at the outlet of the nth furnace roller is a steady-state function of first-order inertia output when the velocity and the inlet tension of the furnace rollers are known boundary conditions;
1.13 Finally, continuing to derive the above equations (1-12), the general equation for the roll-to-roll tension model between any two rolls is:
in the formula:
Tnthe tension of the intermediate strip steel of the furnace roller n roller is obtained;
Tn-1the tension of the strip steel between the furnace roller n-1;
e is a Young modulus ratio coefficient;
a is the unit sectional area of the strip steel;
vnis the linear velocity of an outlet of a furnace roller n;
vn-1is the linear speed of an inlet n of the furnace roller;
the formula (1-13) is the expression of the tension model between the rollers obtained in the step 1)Formula (I) means the tension T applied to the strip between adjacent furnace rollsnIs the difference value v of linear speeds of two rollersn-vn-1Tension T of strip steel between front and rear adjacent furnace rollersn-1The first-order inertia function of the furnace is in direct proportion to the product of the unit sectional area of the strip steel and in inverse proportion to the linear speed of the furnace roller; when the strip steel in the furnace runs at a constant speed, the specification of the strip steel is determined, and the tension between the rollers is unchanged; when the linear speed of the furnace roller changes, the rotating speed of the furnace roller changes, the larger the rotating speed of the furnace roller is, the longer the length of the conveyed strip steel is, and the smaller the tension between the rollers is; on the contrary, the rotating speed of the furnace rollers is reduced, the conveying capacity of the strip steel is reduced, and the tension between the rollers is increased;
2) And (3) calculating an in-furnace equal tension distribution model:
the in-furnace equal tension distribution model in the step 2) controls and models the in-furnace tension distribution based on the strip steel tension between the rollers, and the model specifically comprises the following steps:
2.1 According to the principle of equivalent change of the tension of the strip steel in the furnace, the tension model between the rollers is combined, and the inlet tension of the annealing furnace is defined as TentThe outlet tension of the annealing furnace is TextWhen the tension is transmitted from the outlet direction to the inlet direction of the annealing furnace, the tension variation of the last furnace roller at the outlet is as follows:
△T＝Text-Tlast (2-1)
in the formula:
Textthe outlet tension of the annealing furnace can be measured by an outlet tension meter of the annealing furnace;
Tlastthe tension between the last furnace roller of the annealing furnace;
delta T is the tension variation between the outlet tension of the annealing furnace and the last furnace roller at the outlet;
2.2 N) tension value variation between furnace rolls:
△Tn＝Tn-Tn-1 (2-2)
in the formula:
Tnis the tension between the furnace roller n;
Tn-1is the tension between the furnace roller n-1;
△Tnis the tension difference between any adjacent rollers;
2.3 Tension transmission and the ideal state of equal tension change, the tension change amount between the first furnace roller at the inlet of the annealing furnace:
△T1＝T2-T1＝T1-Tent (2-3)
in the formula:
T2is the tension between the furnace roller 2;
T1the tension between the furnace roller 1 and the roller;
Tentthe annealing furnace inlet tension can be measured by an annealing furnace inlet tensiometer;
△T1the tension difference between the adjacent furnace rollers 1;
2.4 When the annealing furnace tension is ideally distributed:
because the inlet tension and the outlet tension are equal to each other in actual production, the ideal tension control effect is that the sum of the tension variation in the furnace is 0, namely
Assuming that the tension distribution in the furnace is in an ideal state, the tension in the furnace is changed in an equivalent manner, and the condition of uniform tension distribution between furnace rollers is met, namely the tension variation of the strip steel between adjacent furnace rollers is consistent and is also | [ delta ] T |; the tension in the annealing furnace changes in equal quantity between adjacent furnace rollers, the tension is reduced to 0 in the middle of the annealing furnace, in order to enable the middle of the annealing furnace to have zero tension, the speed of the annealing furnace is given by taking the furnace roller in the middle of the annealing furnace as a reference, the superposition speed for controlling the tension change is generated from the middle of the annealing furnace to two sides, an inlet tension meter and an outlet tension meter are taken as tension references, the tension is transmitted into the annealing furnace, the tension change quantity of an inlet and an outlet of the annealing furnace is equal in size and opposite in direction;
therefore, the furnace equal tension control model is as follows:
designing a new tension control scheme, respectively controlling the tension of an inlet of the annealing furnace and the tension of an outlet of the annealing furnace, and adding an inlet tension controller and an outlet tension controller of the annealing furnace, wherein the inlet tension controller controls a No. 1 roller at the inlet of the annealing furnace to a No. 2 roller in the middle of the annealing furnace (n-1), and the outlet tension controller controls a No. 2 roller in the middle of the annealing furnace to a No. n roller at the outlet of the annealing furnace;
in this step, the input control amount of the tension controller is respectively delta Tent、△TextThe number of furnace rollers in the annealing furnace is n, and n/2 furnace rollers in the middle of the annealing furnace are used as the speed reference of the annealing furnace;
the tension variation between the furnace rollers at the inlet section is as follows:
the tension variation between the furnace rollers at the outlet section is as follows:
in the above formulas (2-5), (2-6):
TTM1is an annealing furnace inlet tensiometer measurement;
TTM2is an annealing furnace exit tensiometer measurement;
△Tentthe tension change value between the furnace rollers at the inlet section of the annealing furnace is used, and the furnace rollers output positive torque;
△Textthe tension change value between the furnace rollers at the outlet section of the annealing furnace is used, and the furnace rollers output negative torque;
3) Genetic algorithm tension control logic:
the genetic algorithm tension control logic in the step is based on an artificial intelligence algorithm and combines the characteristics of industrial PLC automatic control logic to realize the tension control of the annealing furnace, and the genetic algorithm tension control logic specifically comprises the following steps:
according to the genetic algorithm operation rule:
GA＝(C,E,P0,M,Φ,Γ,Ψ,T) (3-1)
in the formula: c is a data sorting mode of chromosome individuals, and the data lengths of the chromosome individuals in GA are consistent;
e is the fitness function of the individual;
P0is an initial population;
m is the population data volume;
phi, gamma and psi are respectively a selection operator, a crossover operator and a mutation operator;
t represents an algorithm termination condition, namely iteration times;
as shown in fig. 1, the genetic algorithm tension control logic designs the tension controller control logic by combining the logic control of the industrial PLC according to the above genetic algorithm operation rules, as follows:
for each furnace roller motor, reading a torque value output by the current motor, writing the torque value into a transmission control background data block, then using a torque variable in a corresponding address as a chromosome parent individual, performing iterative computation of a genetic algorithm, then writing data meeting fitness into data qualification of a child individual, performing cyclic computation, and finally outputting an optimal solution control quantity and then performing tension control;
4) After the steps 1) to 3) are finished, outputting a difference value between the strip steel tension and the tension change between adjacent furnace rollers by a furnace roller motor through adopting the tension control model between the rollers in the step 1) and the tension distribution model in the furnace in the step 2), independently controlling the output of the furnace roller motor, taking a furnace roller theoretical tension value as a control target, inputting the actual furnace roller tension by a tension controller, and finally generating a superposition speed through a speed adapter by using the control quantity of the tension controller after iterative calculation of a genetic algorithm in the genetic algorithm tension control logic in the step 3) to control the tension between the rollers in the furnace.
Step 4) the control scheme of the tension controller in the genetic algorithm tension control logic is as follows:
the tension of the strip steel of each motor at the moment of a sampling period is read as an individual numerical value in a chromosome, the theoretical value of the tension between the rollers is used as the cyclic control of fitness, the final result is converged, the iteration frequency limit is cancelled, the tension control is kept, the optimal solution control quantity after iteration is used as the input of a control variable, the control variable is converted into an additional speed through a speed adapter and is sent to a furnace roller motor inversion unit to realize the tension control, and the tension control effect after the optimization is verified through the acquisition and comparison of process data.
Referring to fig. 2, in this embodiment, the detailed control implementation manner of the genetic algorithm tension control logic in step 4) and the corresponding device operating state are as follows:
(1) Population representation and initialization logic:
because the output tension of the furnace roller of the collection object is continuous data, no specific coding rule is needed for population initialization, and the tension value between the furnace rollers is sampled and calculated by adopting the idea of calculating the optimal solution by the circular iteration of a genetic algorithm. According to the idea of genetic algorithm, an initial population is required to be created, and actual torque values are continuously read in an array form in PLC logic according to periods.
Defining [ Chrom1, nind1, lind1], creating a 5 × 20 binary matrix as a torque output population Chrom1, the number of individuals Nind1=5, and the length Lind1=20, then the initial population contains the number of chromosomes Nind1, each chromosome contains the number of genes Lind1, and the load torques at different times are converted into roller tension values as a solution set, i.e., each individual chromosome contains 20 torque values at different times.
When the machine annealing furnace runs, the furnace rollers rotate at the speed of the machine set as a linear speed, the torque current component in the furnace roller current is converted into a tension value between the furnace rollers through calculation, and the data block address corresponding to each furnace roller is read and written according to the PLC scanning period of 50 ms. If addresses 1-20 are defined as chromosome 1 and addresses 81-100 are defined as chromosome 5. At this time, the controller is put into operation soon, iterative calculation is insufficient, and data fluctuation in each chromosome is large.
(2) Fitness computation logic:
and calculating the fitness of the chromosome according to the definition of a function rule of a genetic algorithm. The control logic is as follows: a new chromosome array [ Chrom2, nind2, lind2] was defined with the same rules as population 1. Calculating the magnitude relation between the tension value between 20 rollers in each chromosome and the absolute value of the tension variation between the rollers in the equal tension model, setting an adjustable control precision percentage coefficient as the fitness of the genetic algorithm tension control, judging the tension deviation value between the rollers, writing data meeting the control target range into the data address of the new chromosome Chrom2, feeding back to the fitness calculation logic, and performing circular iterative calculation control.
For example, setting the control precision proportionality coefficient to be 10%, directly taking the data with the deviation value less than 10% as an approximate solution, sequentially writing the data addresses of the new chromosome 2, continuously participating in fitness calculation of the initial population by the new array Chrom2, continuously reading newly acquired tension data between rollers by the original address in Chrom1, and circularly and iteratively calculating the subsequent genetic algorithm in the form.
(3) Selecting function logic:
the control logic adopts an optimal individual retention method, acquires a real-time tension value between the rollers by the Chrom1, calculates the fitness, and directly retains chromosome data which is subjected to cyclic iteration in the Chrom2 and is continuously close to a tension target value between the rollers.
(4) Cross operator logic:
the crossover operators are divided into discrete recombination, intermediate recombination and linear recombination. In the theory of genetic algorithm crossover operators, there is the meaning of chromosome exchange recombination, and a crossover operator is understood to be the structural adjustment of individuals between chromosomes. And (4) carrying out exchange recombination on the chromosome by using a crossover operator.
Discrete recombination is the exchange of variable values between chromosomes, and the data exchange of corresponding positions is performed according to the individual sequence after the linear arrangement of the previous process. The individual positions of the chromosomes exchanged should correspond. The crossing mode simulates an actual chromosome exchange information mode and has certain imitative property. The generated new chromosome has the characteristics of a father individual, and new chromosome information is created as a calculation method of an artificial intelligence irregular function.
During cross iterative calculation, discrete recombination is adopted for data change of a cross operator part, and corresponding position exchange is carried out on individuals 5, 10, 15 and 20 in adjacent chromosomes in a Chrom2 array. The chromosome information exchange generated by the simulation organism for adapting to the environment is simulated.
(5) Mutation operator logic:
the original meaning of the mutation operator part in the genetic algorithm is that when the gene data in part of individuals are transformed, under the condition that the iteration times are not reached and the local optimal solution is calculated too early, the overall calculated amount can be deviated, and too early convergence is avoided. In the optimization scheme, data with large deviation from fitness is artificially generated to serve as variant individuals.
The logic is that, during the variation calculation, a certain fixed item of each chromosome, for example, the 10 th and 20 th data in the chromosome, is multiplied by a fixed coefficient of 110%, so that the torque value jumps to change the sampling mean value of the data in the chromosome, and the variation item is added during the loop iteration, so that the convergence and optimal solution process is slowed down to prevent local convergence rather than global optimal solution.
(6) The optimal solution calculation logic of the genetic algorithm is as follows:
and finally, canceling the limitation of iteration times in the genetic algorithm, circularly calculating chromosome data in Chrom2, writing the mean value of the corresponding chromosome genes in the sub-individuals into the optimal solution chromosome, serving as the optimal solution of the tendency of the data of the sub-individuals after iteration, and participating in tension control of the speed adapter.
At the moment, because the iteration times defined in the genetic algorithm are cancelled, the form tension controller works continuously, the optimal tension solution is calculated in a circulating mode, meanwhile, the output torque output to the transmission control is given, the acquired value of the tension between the rollers in the father individual is converged continuously, the acquired value is subjected to simulated evolution through the genetic operator of the son individual, the tension data between the rollers of the furnace with dynamic change is controlled by taking the theoretical value of the tension between the rollers as a target, and finally, stable control quantity is output. The real-time acquisition characteristic of the algorithm enables the iterative optimal solution to have real-time performance, eliminates control lag in proportional-integral control, and is superior to proportional-integral control in the prior art.
Example 2
Taking the setting values of the tension inlet and outlet of the annealing furnace as 2644N as an example, randomly selecting 4 adjacent furnace rollers of a heating section RTF, an electric heating section HEF and a soaking section SF of the radiant tube in the same data acquisition period and acquisition time, and recording the calculated value of the tension of the furnace rollers acting on strip steel. The mean values of the data over the acquisition period are shown in table 1:
TABLE 1 tension data acquisition
As can be seen from the table 1, the artificial intelligent automatic control method for the tension of the annealing furnace has the advantages that the output torque direction of the HEF22# furnace roller is negative before use, the control is carried out according to the zero tension theory in the furnace after use, the HEF22# furnace roller is used as the annealing furnace, the speed is given, the additional speed is 0.24mpm, the output tension is-4N, the method is consistent with the control scheme, and the distribution uniformity of the tension in the furnace is improved.
After the device is used, the fluctuation range of the output tension of the furnace roller in sampling time of each section is reduced from 13-30N to 2-8.5N, the average fluctuation range is reduced by about 70%, and the control stability of the tension in the furnace is improved.
The tension of the annealing furnace is transmitted from the outlet tension meter to the inlet before use, the tension in the furnace is integrally controlled and adjusted, the tension in the furnace is randomly distributed, and the tension of the annealing furnace is gradually reduced from the inlet and the outlet to the furnace by the same delta T until the tension is reduced to zero at the furnace roller in the middle of the annealing furnace, so that the tension control precision in the furnace is improved.
TABLE 2 Property measurements of non-oriented silicon steel
Referring to the non-oriented silicon steel performance detection data in the table 2, the invention tests the performance data of different grades of non-oriented silicon steel products through quality inspection after use, and compares the product performance before and after implementing furnace tension control, thereby improving the iron loss value of middle and low grade products and improving the magnetic induction intensity of high grade products; the low-frequency alternating current iron loss value of a certain middle and low grade non-oriented silicon steel product is reduced by 0.12-1.53%, and the peak magnetic induction intensity of a certain high grade non-oriented silicon steel product is improved by 1.28%. The magnetic performance of products of various specifications is close to the upper limit of the quality standard of the corresponding grade, the product performance is improved, and the profit margin of the products is increased.
However, those skilled in the art should recognize that the above-described embodiments are illustrative only, and not restrictive, and that changes and modifications to the embodiments described above are intended to be included within the scope of the appended claims.
Claims (2)
1. An artificial intelligent automatic control method for the tension of an annealing furnace comprises three steps of an inter-roller tension control model, an in-furnace equal tension distribution model and a genetic algorithm tension control logic, and specifically comprises the following steps:
1) And (3) calculating an inter-roller tension control model:
the tension model between the rollers in the step 1) takes the tension of the strip steel between the adjacent rollers in the furnace as a research object, and calculates the tension of the strip steel in the furnace, which is as follows:
1.1 According to theoretical mechanics, the tension applied to the strip steel between adjacent furnace rollers in the annealing furnace is analyzed, the stress applied to the solid is in direct proportion to the strain, and the formula is as follows:
σ＝Eε (1-1)
in the formula:
sigma is the stress borne by the strip steel;
epsilon is the strain of the strip steel;
e is a Young modulus ratio coefficient;
1.2 The strain epsilon is equal to the length variation of the strip steel within t time and the length L of the initial moment0The ratio is as follows:
ε＝△L/L0 (1-2)
in the formula:
epsilon is the strain of the strip steel;
delta L is the length variation of the strip steel;
L0the initial length of the strip steel is defined;
1.3 Suppose stress σ between the two rolls0When 0, the initial length of the strip between the rolls is L0If the stress change is σ, the length change of the strip steel is Δ L, and the following two equations can be deduced:
in the formula:
sigma is the stress borne by the strip steel;
e is a Young modulus ratio coefficient;
when delta L is stress sigma, the length change quantity of the strip steel is changed;
L0when the stress between the two rollers is 0, the initial length of the strip steel between the rollers is determined;
1.4 Length change amount:
1.5 The tension of the strip steel between the adjacent furnace rollers is related to the initial length of the strip steel between the furnace rollers and the length of the strip steel sent in and out by the adjacent furnace rollers along the running direction of the strip steel, namely related to the speed difference;
continuously converting the length of the strip steel between the rollers, and the initial length L of the strip steel between two adjacent rollers0Comprises the following steps:
in the formula:
L0when the stress between the two rollers is 0, the initial length of the strip steel between the rollers is determined;
l is the length of stress sigma time borne by the strip steel between the rollers;
sigma is the stress on the strip steel;
e is a Young modulus ratio coefficient;
1.6 For the nth and (n-1) th furnace rollers along the running direction of the strip steel, the initial distance and the stress are as follows:
in the formula:
Ln0is the nth root and the nth root-1 length of strip steel between furnace rollers without external force;
Lnthe strip steel between the two rollers is stressed by a stress of sigmanThe length of time;
1.7 Strip stress sigma between adjacent furnace rollsnIt should be:
1.8 Derived from both sides of the above equation:
in the formula:
dσnthe variation of the stress borne by the strip steel between the nth furnace roller and the (n-1) th furnace roller is shown;
Lnthe strip steel between the two rollers is stressed by a stress of sigmanThe length of time;
dLnthe length variation of the outlet of the nth furnace roller is obtained;
dLn-1the length variable quantity of the inlet of the nth furnace roller is obtained;
σnnamely the stress borne by the strip steel between the outlet rollers of the nth furnace roller;
σn-1namely the stress borne by the strip steel between the inlet rollers of the nth furnace roller;
e is the Young modulus ratio coefficient;
1.9 The above-mentioned formulas (1-8) reflect the amount of change σ in stress between adjacent rollsnThe length variation dL of the strip steel at the inlet and the outlet of the rolln、dLn-1In relation to the linear velocity v of furnace roller nnAt run-time, within unit time dt:
the variation of the outlet length of the nth roll is as follows:
dLn＝vn+1dt；
the n-th roll inlet length variation is:
dLn-1＝vndt；
namely, the above formula (1-8) is modified to:
in the formula:
dσnthe variation of the stress borne by the strip steel between the nth furnace roller and the (n-1) th furnace roller is shown;
Lnthe strip steel between the two rollers is stressed by a stress of sigmanThe length of time;
vnis the nth roller outlet linear velocity;
vn-1is the n-th roller inlet linear velocity;
σnnamely the stress borne by the strip steel between the outlet rollers of the nth furnace roller;
σn-1namely the stress borne by the strip steel between the inlet rollers of the nth furnace roller;
dt is a unit time;
e is the Young modulus ratio coefficient;
1.10 Obtained by further working up the above equations (1-9):
1.11 In the above formula (1-10),
the above equation is simplified as:
1.12 A lagrange transformation is performed on both sides of the above equation (1-11) to obtain:
in the formula:
meaning the length of the strip steel at the outlet n of the furnace roller and the linear velocity v of the rollernThe ratio, i.e. the time consumed by the furnace roller n is constant t for a greater number of revolutionsnThe smaller the stress is, the smaller the stress borne by the strip steel at the n outlet of the furnace roller is;
equations (1-12) indicate that: the linear velocity of the nth furnace roller can control the strip steel stress between the rollers of the adjacent furnace rollers, namely the strip steel tension at the outlet of the nth furnace roller is a steady function of first-order inertial output when the velocity and the inlet tension of the furnace rollers are known boundary conditions;
1.13 Finally, continuing to derive the above equations (1-12), the general equation for the roll-to-roll tension model between any two rolls is:
in the formula:
Tnthe tension of the intermediate strip steel of the furnace roller n roller is obtained;
Tn-1the tension of the strip steel between the furnace roller n-1;
e is the Young modulus ratio coefficient;
a is the unit sectional area of the strip steel;
vnis the linear velocity of an outlet of a furnace roller n;
vn-1is the linear speed of an inlet n of the furnace roller;
the formula (1-13) is a model expression of the tension between the rollers obtained in the step 1), and means the tension T borne by the strip steel between the rollers of the adjacent furnace rollersnIs the difference value v of linear speeds of two rollersn-vn-1Tension T of strip steel between front and rear adjacent furnace rollersn-1The first-order inertia function of the furnace is in direct proportion to the product of the unit sectional area of the strip steel and in inverse proportion to the linear velocity of the furnace roller; when the strip steel in the furnace runs at a constant speed, the specification of the strip steel is determined, and the tension between the rollers is unchanged; when the linear velocity of the furnace roller changes, the rotating speed of the furnace roller changes, the larger the rotating speed of the furnace roller is, the longer the length of the conveyed strip steel is, and the smaller the tension force between the rollers is; on the contrary, the rotating speed of the furnace roller is reduced, the conveying capacity of the strip steel is reduced, and the tension between the rollers is increased；
2) And (3) calculating an in-furnace equal tension distribution model:
the in-furnace equal tension distribution model in the step 2) controls and models the in-furnace tension distribution based on the strip steel tension between the rollers, and the model specifically comprises the following steps:
2.1 According to the principle of equivalent change of the tension of the strip steel in the furnace, the tension model between the rollers is combined, and the inlet tension of the annealing furnace is defined as TentThe outlet tension of the annealing furnace is TextWhen the tension is transmitted from the outlet direction to the inlet direction of the annealing furnace, the tension variation of the last furnace roller at the outlet is as follows:
△T＝Text-Tlast (2-1)
in the formula:
Textthe annealing furnace outlet tension can be measured by an annealing furnace outlet tension meter;
Tlastthe tension between the last furnace roller of the annealing furnace;
delta T is the tension variation between the outlet tension of the annealing furnace and the last furnace roller at the outlet;
2.2 N) tension value variation between furnace rolls:
△Tn＝Tn-Tn-1 (2-2)
in the formula:
Tnis the tension between the furnace roller n;
Tn-1is the tension between the furnace roller n-1;
△Tnis the tension difference between any adjacent rollers;
2.3 Tension transmission and the ideal state of equal tension change, the tension change amount between the first furnace roller at the inlet of the annealing furnace:
△T1＝T2-T1＝T1-Tent (2-3)
in the formula:
T2is the tension between the furnace roller 2;
T1the tension between the furnace roller 1 and the roller;
Tentthe annealing furnace inlet tension can be measured by an annealing furnace inlet tensiometer;
△T1the tension difference between the adjacent rollers of the furnace roller 1;
2.4 When the annealing furnace tension is ideally distributed:
because the inlet tension and the outlet tension are equal to each other in actual production, the ideal tension control effect is that the sum of the tension variation in the furnace is 0, namely
Assuming that the tension distribution in the furnace is in an ideal state, the tension in the furnace is changed in an equivalent manner, and the condition of uniform tension distribution between furnace rollers is met, namely the tension variation of the strip steel between adjacent furnace rollers is consistent and is also | [ delta ] T |; the tension in the annealing furnace changes in equal quantity between adjacent furnace rollers and is reduced to 0 to the middle of the annealing furnace, in order to ensure zero tension in the middle of the annealing furnace, the speed of the annealing furnace is given by taking the furnace rollers in the middle of the annealing furnace as a reference, the superposition speed for controlling the tension change is generated from the middle of the annealing furnace to two sides, an inlet tension meter and an outlet tension meter are taken as tension references, the tension is transmitted into the annealing furnace, the tension variable quantities of an inlet tension and an outlet tension of the annealing furnace are equal in size and opposite in direction;
therefore, the furnace equal tension control model is as follows:
designing a new tension control scheme, respectively controlling the tension of an inlet of the annealing furnace and the tension of an outlet of the annealing furnace, and adding an inlet tension controller and an outlet tension controller of the annealing furnace, wherein the inlet tension controller controls a No. 1 roller at the inlet of the annealing furnace to a No. 2 roller in the middle of the annealing furnace (n-1), and the outlet tension controller controls a No. 2 roller in the middle of the annealing furnace to a No. n roller at the outlet of the annealing furnace;
in this step, the input control amount of the tension controller is respectively delta Tent、△TextThe number of furnace rollers in the annealing furnace is n, and n/2 furnace rollers in the middle of the annealing furnace are used as the speed reference of the annealing furnace;
the variable quantity of the tension between the furnace rollers at the inlet section is as follows:
the tension variation between the furnace rollers at the outlet section is as follows:
in the above formulas (2-5), (2-6):
TTM1is an annealing furnace inlet tensiometer measurement;
TTM2is an annealing furnace exit tensiometer measurement;
△Tentthe tension change value between the furnace rollers at the inlet section of the annealing furnace is used, and the furnace rollers output positive torque;
△Textthe tension change value between the furnace rollers at the outlet section of the annealing furnace is used, and the furnace rollers output negative torque;
3) Genetic algorithm tension control logic:
the genetic algorithm tension control logic in the step is based on an artificial intelligence algorithm and combines the characteristics of industrial PLC automatic control logic to realize the tension control of the annealing furnace, and the genetic algorithm tension control logic specifically comprises the following steps:
according to the genetic algorithm operation rule:
GA＝(C,E,P0,M,Φ,Γ,Ψ,T) (3-1)
in the formula: c is a data sorting mode of chromosome individuals, and the data lengths among the chromosome individuals in GA are consistent;
e is the fitness function of the individual;
P0is an initial population;
m is the population data volume;
phi, gamma and psi are respectively a selection operator, a crossover operator and a mutation operator;
t represents an algorithm termination condition, namely iteration times;
the genetic algorithm tension control logic designs a logic control scheme of the tension controller by combining the logic control of the industrial PLC according to the genetic algorithm operation rule, and the logic control scheme comprises the following steps:
reading a torque value output by a current motor for each furnace roller motor, writing the torque value into a transmission control background data block, performing iterative calculation of a genetic algorithm by taking a torque variable in a corresponding address as a chromosome parent, writing data meeting fitness into data quality of a child individual, performing cyclic calculation, and finally outputting an optimal solution control quantity and then performing tension control;
4) After the steps 1) to 3) are finished, outputting a difference value between the strip steel tension and the tension change between adjacent furnace rollers by a furnace roller motor through adopting the tension control model between the rollers in the step 1) and the tension distribution model in the furnace in the step 2), independently controlling the output of the furnace roller motor, taking a furnace roller theoretical tension value as a control target, inputting the actual furnace roller tension by a tension controller, and finally generating a superposition speed through a speed adapter by using the control quantity of the tension controller after iterative calculation of a genetic algorithm in the genetic algorithm tension control logic in the step 3) to control the tension between the rollers in the furnace.
2. The method for artificially intelligently and automatically controlling the tension of an annealing furnace according to claim 1, wherein the control scheme of the tension controller in the step 4) genetic algorithm tension control logic is as follows:
the tension of the strip steel of each motor at the moment of a sampling period is read as an individual numerical value in a chromosome, the theoretical value of the tension between the rollers is used as the cyclic control of fitness, the final result is converged, the iteration frequency limit is cancelled, the tension control is kept, the optimal solution control quantity after iteration is used as the input of a control variable, the control variable is converted into an additional speed through a speed adapter and is sent to a furnace roller motor inversion unit to realize the tension control, and the tension control effect after the optimization is verified through the acquisition and comparison of process data.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110483149.XA CN115261600B (en) | 2021-04-30 | 2021-04-30 | Artificial intelligent automatic control method for annealing furnace tension |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110483149.XA CN115261600B (en) | 2021-04-30 | 2021-04-30 | Artificial intelligent automatic control method for annealing furnace tension |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115261600A true CN115261600A (en) | 2022-11-01 |
| CN115261600B CN115261600B (en) | 2023-07-07 |
Family
ID=83744781
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110483149.XA Active CN115261600B (en) | 2021-04-30 | 2021-04-30 | Artificial intelligent automatic control method for annealing furnace tension |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115261600B (en) |
Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB546489A (en) * | 1939-06-22 | 1942-07-16 | Crown Cork & Seal Co | Improvements in or relating to the manufacture of seamless containers |
| AT288459B (en) * | 1967-11-28 | 1971-03-10 | Kloeckner Werke Ag | Device for the selective tempering of base plates with one or more gripping bars |
| DE2435210A1 (en) * | 1974-07-22 | 1977-02-17 | All Technik Gmbh | Bearing rings and elements mfr. - by pressing rings from flat stock and forming balls from the outer zones of rolled slab |
| SU863673A1 (en) * | 1978-05-31 | 1981-09-15 | Ростовский-на-Дону научно-исследовательский институт технологии машиностроения | Method of thermal treatment of carbon austenite steels |
| CN103834793A (en) * | 2012-11-22 | 2014-06-04 | 宝山钢铁股份有限公司 | Method for monitoring distribution of internal tension of continuous annealing horizontal furnace |
| CN107245647A (en) * | 2017-06-01 | 2017-10-13 | 东北大学 | The method that one kind prepares flourishing { 100 } plane texture non-orientation silicon steel thin belt based on thin strap continuous casting |
| CN108018485A (en) * | 2017-10-24 | 2018-05-11 | 北京首钢股份有限公司 | Annealed sheet and its production method |
| CN108359775A (en) * | 2018-02-27 | 2018-08-03 | 首钢京唐钢铁联合有限责任公司 | The setting method of vertical continuous annealing furnace tension |
| CN108677002A (en) * | 2018-05-16 | 2018-10-19 | 山西太钢不锈钢股份有限公司 | A kind of stove internal tension compensating control method suitable for tandem rolling Horizental annealer |
| CN109022757A (en) * | 2017-06-09 | 2018-12-18 | 上海梅山钢铁股份有限公司 | The dynamic segmentation control method of tin-plated product annealing temperature |
| CN110788143A (en) * | 2019-11-08 | 2020-02-14 | 中冶南方工程技术有限公司 | Thickness compensation method for acceleration and deceleration stages of rolling mill |
-
2021
- 2021-04-30 CN CN202110483149.XA patent/CN115261600B/en active Active
Patent Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB546489A (en) * | 1939-06-22 | 1942-07-16 | Crown Cork & Seal Co | Improvements in or relating to the manufacture of seamless containers |
| AT288459B (en) * | 1967-11-28 | 1971-03-10 | Kloeckner Werke Ag | Device for the selective tempering of base plates with one or more gripping bars |
| DE2435210A1 (en) * | 1974-07-22 | 1977-02-17 | All Technik Gmbh | Bearing rings and elements mfr. - by pressing rings from flat stock and forming balls from the outer zones of rolled slab |
| SU863673A1 (en) * | 1978-05-31 | 1981-09-15 | Ростовский-на-Дону научно-исследовательский институт технологии машиностроения | Method of thermal treatment of carbon austenite steels |
| CN103834793A (en) * | 2012-11-22 | 2014-06-04 | 宝山钢铁股份有限公司 | Method for monitoring distribution of internal tension of continuous annealing horizontal furnace |
| CN107245647A (en) * | 2017-06-01 | 2017-10-13 | 东北大学 | The method that one kind prepares flourishing { 100 } plane texture non-orientation silicon steel thin belt based on thin strap continuous casting |
| CN109022757A (en) * | 2017-06-09 | 2018-12-18 | 上海梅山钢铁股份有限公司 | The dynamic segmentation control method of tin-plated product annealing temperature |
| CN108018485A (en) * | 2017-10-24 | 2018-05-11 | 北京首钢股份有限公司 | Annealed sheet and its production method |
| CN108359775A (en) * | 2018-02-27 | 2018-08-03 | 首钢京唐钢铁联合有限责任公司 | The setting method of vertical continuous annealing furnace tension |
| CN108677002A (en) * | 2018-05-16 | 2018-10-19 | 山西太钢不锈钢股份有限公司 | A kind of stove internal tension compensating control method suitable for tandem rolling Horizental annealer |
| CN110788143A (en) * | 2019-11-08 | 2020-02-14 | 中冶南方工程技术有限公司 | Thickness compensation method for acceleration and deceleration stages of rolling mill |
Non-Patent Citations (1)
| Title |
|---|
| 张峰;吕学钧;马长松;陈晓;: "生产工艺及成分体系对含磷无取向硅钢磁性能的影响", 钢铁钒钛, no. 03, pages 70 - 76 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115261600B (en) | 2023-07-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100584476C (en) | Tension control system and method for planetary gear structure tension roller type evener | |
| CN100493748C (en) | Control method for dynamically correcting strip steel thickness deviation by forward slip adaption | |
| CN102151704B (en) | Stelmor line cooling method of high-speed wire by taking temperature as direct-control parameter | |
| US6546310B1 (en) | Process and device for controlling a metallurgical plant | |
| CN102688900B (en) | Method for guaranteeing hot continuous rolling mill finish rolling outlet temperature | |
| CN109001979A (en) | Blast-melted quality adaptation Robust Predictive Control method based on Lazy learning | |
| CN204595644U (en) | Based on the aluminum-bar heating furnace temperature of combustion automaton of neural network | |
| CN110607435B (en) | Annealing furnace plate temperature control system and method | |
| CN105344720B (en) | A kind of On-Line Control Method of fine-rolling strip steel finishing temperature | |
| Ali et al. | Automatic voltage generation control for two area power system based on particle swarm optimization | |
| CN111443597B (en) | Device and method for controlling granularity of vertical mill mineral powder | |
| CN115261600A (en) | Artificial intelligence automatic control method for annealing furnace tension | |
| CN109763085B (en) | Method for controlling temperature of alloying section of hot galvanizing line | |
| Wang et al. | Signal-compensation-based adaptive PID control for fused magnesia smelting processes | |
| CN109062030A (en) | Thermal power unit plant load prediction PID control method based on laguerre function model | |
| CN110770357B (en) | Method for operating annealing furnace | |
| Che et al. | Optimization of schedule with multi-objective for tandem cold rolling mill based on IAGA | |
| Guo et al. | Fractional-order PID dynamic matrix control algorithm based on time domain | |
| Mikitinskiy et al. | Synthesis of Adaptive Tension Control System Used in Winding of Some “Dry” Composite Material Products | |
| CN1753734A (en) | Method for regulating the temperature of a metal strip, especially for rolling a metal hot strip in a finishing train | |
| Dong et al. | Research on hydraulic looper system modeling and rbf neural network decoupling control | |
| CN115386720B (en) | Online control method for mechanical properties of cold-rolled continuous annealed steel plate | |
| Liu et al. | Modeling and gain scheduling adaptive control of tension control system for continuous annealing process | |
| Hu et al. | Research on Temperature Control Method of Variable Structure Thermoelectric Furnace Based on Fuzzy PID Optimized by Genetic Algorithm | |
| Dengying et al. | LPV H-infinity controller design for a wind power generator |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |