CN106435427A - Air knife distance optimization control method applied to galvanization production - Google Patents
Air knife distance optimization control method applied to galvanization production Download PDFInfo
- Publication number
- CN106435427A CN106435427A CN201610650208.7A CN201610650208A CN106435427A CN 106435427 A CN106435427 A CN 106435427A CN 201610650208 A CN201610650208 A CN 201610650208A CN 106435427 A CN106435427 A CN 106435427A
- Authority
- CN
- China
- Prior art keywords
- air knife
- coating
- thickness
- distance
- error
- 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
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/14—Removing excess of molten coatings; Controlling or regulating the coating thickness
- C23C2/16—Removing excess of molten coatings; Controlling or regulating the coating thickness using fluids under pressure, e.g. air knives
- C23C2/18—Removing excess of molten coatings from elongated material
- C23C2/20—Strips; Plates
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C2/00—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor
- C23C2/04—Hot-dipping or immersion processes for applying the coating material in the molten state without affecting the shape; Apparatus therefor characterised by the coating material
- C23C2/06—Zinc or cadmium or alloys based thereon
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Coating With Molten Metal (AREA)
Abstract
The invention provides an air knife distance optimization control method applied to galvanization production and aims to overcome working condition deviation of the production line or thickness deviation, caused by other factors, of a front galvanized layer and a rear galvanized layer, to guarantee the uniformity of the front galvanized layer and the rear galvanized layer and also to optimize the air knife distance when the pressure of each air knife is within a saturation critical area so as to guarantee the air knife pressure adjustment margin during feedback control. When the front galvanized layer and the rear galvanized layer are different in thickness, the thickness deviation mean value of the front galvanized layer and the rear galvanized layer within a counted time is taken as input to calculate a corrected value of the distance of front and rear air knifes by virtue of a neural network so as to respectively adjust the distance between the air knifes at the front and rear sides; when the pressure of each air knife is within a saturation region, a reasonable distance of the front and rear air knifes is calculated based on a neural network mode, the current air knife pressure, the current air knife distance, the air knife pressure preset margin and the speed of the production line so as to obtain an air knife pressure set value and an air knife distance set value which satisfy the current control precision and also have adjustment margin.
Description
Technical field
The present invention relates to zinc-plated production field, more particularly, to a kind of zinc-plated production air knife is apart from optimal control method.
Background technology
Enter 21st century, China by big steel country march toward iron and steel power.Industry restructuring, develops deep processing
And high value added product, the competitiveness improving product is the developing direction of China's steel and iron industry.
However, according to statistics, China accounts for 1/3rd of the world's total metal annual production because of the metallic article that corrosion is scrapped every year,
Illustrate that the etching problem solving steel has very important economic implications to China.Zincincation can effectively prevent steel
Corrosion, increases the service life, and the quality of coating is the weight that the Automobile Plate user in downstream or appliance plate use producer's concern and examination
Point, therefore, steelmaker in order to while meeting galvanizing production prescription control production cost, to zinc coating thickness control
Level proposes strict requirements.
For lifting the zinc-plated automatization level producing and controlling, at present, thickness of coating automatic control system is gradually looked forward at some
Used in industry, based on its commonly used air pressure, air knife distance supplemented by feedback, make air knife as far as possible
Distance keeps constant, is main control variable with air pressure, thickness measuring apparatus measuring value realizes closing of thickness of coating for feedback quantity
Ring controls.This feedback closed loop controls can make strip coating thickness approach setting value as far as possible, for the control of lifting Zinc Coating Thickness
Precision, reduces thickness of coating fluctuation, reduces the luxus consumption of zinc, serve certain effect.However, due to zinc-plated production process
Process characteristic, there are two inherent shortcomings in common feedback controling mode.
1), coating offset issue in front and back.Above-mentioned feedback control scheme is to be with the thickness of coating summation of coating front and rear surfaces
Controlled variable, makes the thickness of coating summation of strip steel front and rear surfaces follow the tracks of upper setting value.However, Zinc Coating Thickness control targe also includes
An other important quality index, i.e. the uniformity of strip steel front and rear surfaces coating, if the thickness of coating deviation of front and rear surfaces
Excessive, lead to product not meet quality standard, larger economic loss can be caused.However, in actual production process, due to band
The factors such as steel plate type, working roller abrasion, machine error affect, even if under stable operating mode, strip steel front and rear surfaces thickness of coating
Also occur and fluctuate by a relatively large margin.And because strip steel centrage is with the mechanical zero of air knife in front and back and misaligned (side gas before and after i.e.
The knife of knife away from measured value and is not equal to itself actual range and strip steel centrage between), therefore pass through unilateral air knife before and after adjustment
Before and after distance elimination, the method for thickness of coating deviation has very big difficulty.
2), pressure saturation problem.Air pressure adjusts and is limited presence regulation zone of saturation (i.e. by gas path pipe pressure
Air pressure can not be more than gas path pipe pressure, when air pressure is close to pipeline pressure, increases regulating valve, air knife in any case
Pressure also cannot increase), during air pressure unsaturation, when coating producing line velocity variations or other interference factors lead to is thick
During degree change, control system can change it is ensured that zinc-plated by adjusting air pressure and eliminating the thickness of coating that bring of above-mentioned disturbance
The quality of product conforms to quality requirements；And air pressure is when being in saturation region, when external disturbance occurs, air pressure cannot
Increase, lose regulating power, operator have to ensure that air pressure has enough controls by reducing line speed
Allowance processed makes thickness of coating meet quality index to require, and the reduction of line speed is so that the production capacity of upstream and downstream operation and section
Play and be all subject to extreme influence, substantial amounts of economic damage can be brought along with certain zinc coating thickness quality fluctuation to factory simultaneously
Lose.
Content of the invention
The technical problem to be solved in the present invention is that in zinc-plated production feedback control, coating deviation and air pressure are adjusted in front and back
The problem of saturation.
In order to solve this technical problem, the invention provides a kind of zinc-plated production air knife, apart from optimal control method, wraps
Include following steps：
S1：Read forward and backward thickness of coating measured value, if memory area is less than being stored in memory area by institute's Thickness Measurement by Microwave, enter
Enter step S4；If memory area is full, enter step S2；
S2：Replace earliest measured value in memory area using current measured value, then, before judging in memory area,
Whether coating deviation average CW_bias exceedes the threshold value of before and after's drift correction afterwards；If exceeding, enter step S3, if not less than,
Then enter step S4；
S3：Optimum is calculated according to air knife distance, air pressure, line speed and thickness of coating departure real-time optimization
Air knife distance, so that it is determined that forward and backward air knife is apart from knots modification GF_delta and GB_delta；Wherein, front thickness of coating needs to change
The departure becoming is-CW_bias/2, and it is CW_bias/2 that rear thickness of coating needs the departure changing；Then, enter step S5；
S4：Make forward and backward air knife be 0 apart from knots modification, enter step S5；
S5：Judging whether air pressure enters zone of saturation, if entering, entering step S6, if being introduced into, entering step
Rapid S7；
S6：Increase air pressure and adjust allowance, according to current air knife distance, line speed, increase the air knife after allowance
Pressure, using neural computing thickness of coating predictive value, and then obtains the departure of thickness of coating；
And then, calculated according to the departure real-time optimization of air knife distance, air pressure, line speed and thickness of coating
Optimum air knife distance, determines air knife apart from knots modification, and then this air knife is averagely allocated to forward and backward air knife apart from knots modification carries out
Change, obtain forward and backward air knife apart from knots modification, enter step S8；
S7：Forward and backward air knife keeps constant apart from knots modification, enters step S8；
S8：Determine that new forward and backward air knife distance sets according to the forward and backward air knife that step S3 and S6 confirm apart from knots modification
Value, is air pressure setting value according to the air pressure that step S6 increases allowance.
Optionally, in described step S6, when using neural computing thickness of coating predictive value, further with god
Obtain thickness of coating predictive value through neural network forecast module；
With strip speed, air knife distance, air pressure for input, thickness of coating is output to described neural network prediction module
Set up, and it learnt based on the historical data of galvanizing process, so the strip speed according to current operation, air knife away from
From the sampled value with air pressure, thickness of coating is predicted.
Optionally, in described step S6, the thickness of coating of required compensation is：
CWm=NN (D (t), P (t), S (t))-NN (D (t), Pini,S(t))
Wherein, D (t) is the air knife distance of t, and P (t) is the air pressure of t, and S (t) is the production line of t
Speed；PiniIt is to increase the air pressure after allowance, also for new air pressure setting value.
Optionally, in described step S3 and/or S6, optimize calculate optimum air knife apart from when, using real-time optimization mould
Block optimization calculates optimum air knife distance；
Described real-time optimization module with the minimum deviation between thickness of coating predictive value and control targe as target, with gas
Knife is constraint apart from traffic coverage, optimum under air pressure, line speed and thickness of coating setting value that iterative search gives
Air knife distance.
Optionally, the real-time optimization algorithm that described real-time optimization module is adopted is specifically described as：
Object function：min|CWt-CWp|
Decision variable：D
Constraints：
CWp=NN (D, Pini,Sini) (6)
CWt=NN (Dini,Pini,Sini)+CWm (7)
D∈[Dmin,Dmax] (8)
Optimizing, wherein increasable algorithm description are iterated according to increment type PID algorithm to D：
Error=CWt-CWp (9)
P_error=error-error_1 (10)
I_error=error (11)
D_error=error-2*error_1+error_2 (12)
△ u=Kp*P_error+Ki*I_error+Kd*D_error (13)
D=D+ △ u (14)
Wherein, the initial value of D is Dini, error_1 is the previous generation value in error iterative calculation, and error_2 is error
Upper secondary value in iterative calculation.By formula (9)～formula (14) iterative calculation, find D and make CWp infinite approach CWt.Excellent in real time
Change algorithm and finally return that air knife, apart from knots modification △ D, meets formula (15)
△ D=D-Dini(15)
In above formula, △ D is in the case of current manufacturing lines speed with air pressure, so that thickness of coating is changed needed for CWm
Total air knife is apart from knots modification, if this knots modification is all applied to front air knife apart from upper, that is, D_front_delta (t)=
△D；According to formula (5), constant in order to ensure thickness of coating, air knife distance should keep constant, and that is, forward and backward knife is apart from knots modification size
Identical, in opposite direction, so, D_back_delta (t)=- △ D.This △ D is the deviation needing change for front thickness of coating
Amount-CW_bias/2, and-△ D be for rear thickness of coating need change departure CW_bias/2 be modified.
The invention discloses the air knife in a kind of Zinc Coating Thickness feedback control is apart from optimization method, it is used for overcoming production lineman
Condition skew or other interference factors cause before and after thickness of coating deviation it is ensured that in front and back coating uniformly, be simultaneously suitable for air knife pressure
Power is in during saturation critical zone and air knife distance is optimized with the regulation allowance it is ensured that air pressure.When in front and back's thickness of coating not
When consistent, applying cladding deviation optimization module, with timing statisticses, thickness of coating deviation average is input in front and back, by nerve net
Network, the correction of air knife distance before and after calculating, respectively in front and back's side air knife distance is adjusted；When air pressure is in saturation region
When, allowance, line speed, meter are reserved based on neural network model and current air pressure, current air knife distance, air pressure
Calculate rational before and after plays distance, both met current control accuracy, have again the air pressure adjusting allowance and air knife away from
From setting value.Method proposed by the invention solves in thickness of coating feedback control because operating mode skew or other disturbances cause
Before and after coating deviation it is ensured that in front and back thickness of coating be uniformly distributed, prevent unilateral thickness of coating situation not up to standard from occurring.With
When, the air pressure being prevented effectively from feedback regulation enters saturation region, contributes to the raising of production line production capacity and the flat of thickness of coating
Surely.
Brief description
Fig. 1 is to be illustrated apart from the system of optimal control method using the zinc-plated air knife that produces in an alternate embodiment of the present invention
Figure；
Fig. 2 be in an alternate embodiment of the present invention zinc-plated produce air knife apart from the detailed process of optimal control method signal
Figure；
Fig. 3 is that in an alternate embodiment of the present invention, thickness of coating setting value controls design sketch when changing；
Fig. 4 is that in an alternate embodiment of the present invention, line speed controls design sketch when changing.
Specific embodiment
The zinc-plated production air knife present invention being provided below with reference to Fig. 1 to Fig. 4 is carried out apart from optimal control method in detail
Description, its be optional embodiment of the present invention it is believed that those skilled in the art do not changing the present invention spirit and content
In the range of, it can be modified and polish.
First, first related problem in prior art and scheme are illustrated：
Galvanizing production is widely used in building, household electrical appliances, automobile and other industries because of its good decay resistance, and coating is too thick
Not only can waste the raw materials such as zinc ingot metal, and the performances such as the spot weldability of product, tack, the resistance to chalking of coating can be affected, and
Coating is too thin, influences whether the corrosion resistance of product, and product quality can not be up to standard.Therefore plating uniformity controls and directly affects
Two aspects to product quality：Thickness of coating and plating uniformity.The main technological parameter of zinc-plated production process includes strip steel
Speed, air knife height, air knife distance and air pressure.Wherein strip speed is subject to annealing furnace production capacity, belt steel thickness and heating
The restriction of system is it is impossible to independent regulation, and air knife height is determined by strip speed, zinc coating thickness is affected less.Therefore, generally
Using on thickness of coating and plating uniformity impact in front and back the most directly air knife distance and air pressure as thickness of coating control
The control variable of system processed.
The air pressure and air knife distance impact relation to thickness of coating is as follows：
(1) under various air pressures, increase the increase that air knife distance can cause zinc coating thickness, particularly under low pressure
Incrementss are bigger.
(2), in nominal situation excursion, increase air pressure and the momentum to galvanized sheet can be led to increase, thus cause zinc
The minimizing of thickness degree.
Continuous hot galvanizing production system has the characteristics that：
(1) on-line measurement of thickness of coating value needs to adopt calibrator, in order to ensure the accuracy measuring, is surveyed using cold conditions
, as the tolerance of thickness of coating, because cold conditions measures the requirement of technique, the installation site of calibrator is usually apart from gas for the result of amount
Farther out, lead to act on the impact to thickness of coating for the controlled quentity controlled variable at air knife needs just can detect after longer time, that is, knife
System has larger measurement delay.
(2) galvanizing process is subject to multiple complicated physical factor such as air force, border fluid layer, heat transfer to act on, final
Before and after zinc coating thickness and coating, uniformity is mainly subject to air knife distance, multiple variables such as air knife air pressure, strip speed coefficient
Impact, and the impact principle to thickness of coating and coating horizontal homogeneity for these variables is complex, has stronger non-linear,
It is difficult to set up accurate system model using traditional modelling by mechanism method；
(3) zinc-plated production process interference factor is numerous, such as air knife height, die gap, the temperature of strip steel, thickness of slab,
Plate width, surface roughness, produce line tension, the factor such as the temperature of zinc pot and chemical composition, belt plate shape and strip steel shake
Change all will produce impact to thickness of coating and in front and back uniformity.
In sum, zinc-plated is typical time-varying large time delay, non-linear, strong disturbance a production process, controls difficulty
Greatly.The experience that current most domestic iron and steel enterprise depends on operative employee adopts manual hand manipulation to combine bottom loop
The mode of PID is controlled, and its control accuracy is low, zinc consumption is big, quality fluctuation big, or even it cannot be guaranteed that thickness of coating and coating
The prescription of the uniformity.Therefore, thickness of coating automatic control system is also gradually used in some enterprises, its for
Improve Zinc Coating Thickness control accuracy and automatization level tool has certain effect.Analyze from principle, current Zinc Coating Thickness system
Commonly used feedback based on air pressure, supplemented by air knife distance, wherein air knife distance refers to before and after both sides
The distance between air knife (i.e. total air knife distance).However, the controlling difficulties being existed due to zinc-plated production process, current feedback
Control method generally faces following two problems：
1), coating offset issue in front and back
Current thickness of coating feedback control system with total air knife distance as control variable, and do not consider forward and backward air knife away from
From concrete distribution.And on the premise of total air knife distance is certain, although the distribution of unilateral air knife distance and coating total thickness in front and back
Degree association less, but directly affects the thickness of unilateral coating in front and back.Before and after generally, the pressure value of side air knife is identical, therefore only
Have in front and back's side air knife apart from consistent when, before and after's thickness of coating can be made consistent, this requires to control strip steel in air knife
Near heart line, also it is to ensure that safety in production simultaneously, prevent air knife from scraping the needs of strip steel.However, due to mechanical reason, in air knife
Heart line cannot be completely superposed with strip steel centrage, there is certain error, simultaneously as there is measurement error, in actual production
There is certain deviation in strip steel central perpendicularity, and cooling tower top roller, sinking roller and stabilizing roller have one with the carrying out producing
Determine the abrasion of degree, lead to this departure to change at any time.In addition, the change with steel plate type also results in it with respect in front and back
The air knife distance of both sides shifts.A series of this disturbance factor leads to during continuous hot galvanizing, even if total air knife distance
Keep constant, before and after its reality, side tool away from being still dynamic change, and then makes strip steel front and rear surfaces thickness of coating fluctuation.
And due to control variable such as air knife distance, air pressures, the impact principle to coating horizontal homogeneity is complex, has stronger
Non-linear, therefore give strip steel front and rear surfaces thickness of coating concordance control bring difficulty.If the coating of front and rear surfaces
Thickness deviation is excessive, leads to product not meet quality standard, can cause larger economic loss.Meanwhile, zinc-plated production system is deposited
In very big measurement delay, if inadequate to the accuracy of in front and back's zinc coat thickness control, before and after's thickness of coating can be led to adjust back
Whole, vibrate.
2), pressure saturation problem
When air pressure is in saturation, air pressure cannot improve again, if air knife distance does not change, thick for meeting coating
Spend demand for control, then line speed cannot be further added by.Therefore air pressure saturation has effect of contraction to production line production capacity.Air pressure
During unsaturation, when occur line speed change or other interference factors lead to thickness of coating change when, control system can
With by adjust air pressure eliminate above-mentioned disturbance bring thickness of coating change it is ensured that the quality of galvanizing production meet quality will
Ask；And when it is in saturation, air pressure cannot increase, lose regulating power, when external disturbance occurs, operator
Member has to ensure that air pressure has enough control allowances so that thickness of coating meets quality by reducing line speed
Index request, the reduction of line speed, so that the production capacity of upstream and downstream operation and rhythm all receive extreme influence, carries to factory
Carry out substantial amounts of economic loss.
For coating offset issue, domestic also have Patents and document to propose System design based on model method, such as public
The number of opening is the patent of CN103510032.A《The deviation control method of cold rolling hot dip galvanizing plating uniformity》, using knife lip aperture
Impact model to thickness of coating, introduces impact efficiency function matrix, improves plating uniformity control accuracy, increase into simultaneously
This function and filter function item, improve coating error function precision, thus improve plating uniformity computational accuracy, make zinc-plated
Product surface quality is improved.However, said method lays particular emphasis on improves transverse uniformity of plating, it is not related to overcome operating mode
The inconsistent situation of coating in front and back that skew and belt steel thickness lead to.
In order to solve the problems, such as air pressure saturation, document《The closed loop control brief introduction of hot galvanizing line zinc coating thickness》(bang
Dragon, Sichuan is metallurgical, and 2006:28 (6)), the zinc coat thickness control system of VAI company offer, this system feedback controller are provided
It is made up of control block and two functional devices of saturate block, call control block first, according to the deviation of thickness of coating, based on air knife pressure
Power, for the yield value of thickness of coating, is calculated air pressure and adjusts knots modification, then according to this air pressure knots modification and
The knots modification that the gain of bottom air pressure closed-loop control system calculates valve opening is added in existing valve opening value, if
Its value is introduced into saturation not less than 80% (regulating power of valve enters zone of saturation), then explanation air pressure, then need not change
Become air knife distance value.Conversely, then entering saturate block, now the regulated quantity of air pressure is set to make valve opening be introduced into satisfying
The upper limit of sum, and calculate the deviation that remaining need in the case of this air pressure pass through the thickness of coating of air knife compensated distance,
Then air knife is calculated apart from adjustment amount to the yield value of thickness of coating according to air knife distance.This regulative mode is based on linear approximation
Calculation of Sensitivity air knife apart from adjustment amount, precision is relatively low, and air pressure is first adjusted to saturation by this regulative mode, reuses
Air knife distance compensates regulation according to residual deviation, air pressure will be led to still in saturation critical state, lose regulation
Allowance.
It can be seen that, although it is contemplated that the problem of plating uniformity in existing thickness of coating feedback control system, but lack and solve
The mechanism of thickness of coating dynamic deviation in front and back, easily produces unilateral thickness situation not up to standard；And simultaneously, although existing system is adopted
With air knife distance, air pressure saturated conditions is compensated, but air knife compensated distance gauge is not calculated and carry out optimizing, lead to
Air pressure after compensation still lacks the allowance of regulation, when external interference is persistently aggravated, needs by constantly regulate gas
Knife distance eliminates the impact of external disturbance, however, knife is adjusted away from by step-length discrete adjustment, with continuously adjustable
Air pressure is compared, and the precision of regulation is poor, and it is poor more than overshoot or larger regulation to be easily caused.
From the point of view of reverting to technical scheme：
In contrast, the purpose of the present invention is the coating deviation in front and back existing for existing thickness of coating feedback control system
The problems such as limited by quality of coating fluctuation that problem and air pressure saturation are brought and production capacity, is it is proposed that a kind of be based on non-linear god
Through the air knife in the Zinc Coating Thickness feedback control of network model apart from optimization method.First, apply nerual network technique, with strip steel
Speed, air knife distance, air pressure are input, and thickness of coating is output, set up zinc-plated production thickness of coating neural network prediction
Model；When before and after occurring, thickness of coating is inconsistent, coating deviation optimization module before and after application, with coating before and after in timing statisticses
Thickness deviation average is input, by neutral net, the correction of air knife distance before and after calculating, and respectively in front and back's air knife distance is entered
Row adjustment；When air pressure is in saturation region, setting air pressure first adjusts space, then passes through neural network model,
Air knife distance in side before and after adjustment.The present invention can in the zinc-plated production process of effectively solving due to operating mode skew, belt steel thickness change or
The inconsistent situation of thickness of coating before and after caused by other reasonses, also can be prevented effectively from the feelings in saturation working area for the pressure work
Condition, it is ensured that adjusting air pressure allowance, significantly improves product quality and coating uniformity in front and back, reduction thickness of coating quality fluctuation,
Remain in the case of lifting production line production capacity ensure that product quality meets index request and other effects.
The present invention proposes a kind of air knife in galvanization production line thickness of coating feedback control apart from optimization method.Can be fast
, when saturation region, rapid optimization air knife distance, eliminates operating mode skew and belt steel thickness becomes for speed reply operating mode skew or pressure work
Change the thickness of coating deviation in front and back brought it is ensured that the adjustment allowance of air pressure, it is ensured that thickness of coating longitudinal uniformity, is carrying
Remain in the case of rising production line production capacity ensure that product quality meets index request, reduce the generation of substandard product.
Before launching to illustrate the method, under first illustrating, the system being suitable for the method can be understood as including neutral net
Prediction module, real-time optimization module, in front and back coating deviation optimization module, four part compositions of saturated pressure optimization module.
Wherein, neural network prediction module be one with strip speed, air knife distance, air pressure for input, coating is thick
Spend the neural network prediction model set up for output, this model learnt based on the historical data of galvanizing process, can root online
Sampled value according to current operation operating mode (strip speed, air knife distance, air pressure) makes accurate prediction to thickness of coating, carries
The impact to thickness of coating for the uncontrolled variable can be surveyed, the adjustment for control variable provides foundation in front precognition galvanizing process.Nerve
Mixed-media network modules mixed-media is the basis of real-time optimization module.
Wherein, described real-time optimization module, this module is between thickness of coating predictive value and zinc coat thickness control target
Minimum deviation be optimization aim, with air knife apart from traffic coverage for constraint, iterative search gives operating mode (air pressure, life
Producing line speed, thickness of coating setting value) under optimum air knife distance.Specifically, what this module solved is an optimization problem, its
Object function is the deviation between thickness of coating predictive value and control targe, and decision variable is air knife distance, and constraints is
Mapping relations between the line speed of neural network prediction module, air knife distance, air pressure and thickness of coating, Yi Jiqi
The technological procedure constraint of knife distance.Eliminate inclined between thickness of coating predictive value and control targe by air knife apart from optimizing
Difference.Real-time optimization module is the basis of before and after's coating deviation optimization module and saturated pressure saturation optimization module.
Wherein, before and after described coating deviation optimization module with before and after strip steel thickness of coating uniformity as control targe,
Operating mode shift and lead to before and after's air knife apart from inconsistent when, ensure total thickness of coating up to standard on the premise of, before and after optimization
Side air knife distance, with coating deviation before and after eliminating.Specifically, before and after occurring during thickness of coating deviation, in order to ensure always to plate
Thickness degree does not change, and before and after's thickness of coating knots modification will be made in the same size, in opposite direction, corresponds, in other works
In the case of condition is immovable, needs to ensure that total air knife distance does not change, and side air knife distance change amount be in the same size in front and back,
In opposite direction.Current working (line speed, air knife distance, air pressure) and the thickness of coating input that need to change in real time
Optimization module, you can the knots modification of air knife distance before and after obtaining respectively.
Wherein, described saturated pressure optimization module is when air pressure is operated in saturation region, optimizes air knife distance, with
Compensate the regulation space of air pressure.When air pressure is in saturation, to reduce air pressure and ensureing that coating is constant,
On the premise of ensureing production safety, then can reduce air knife distance.Wherein, the knots modification of air knife distance according to line speed,
Revised air pressure, line speed and the thickness of coating needing change, calculate gained by real-time optimization module.
Based on four above-mentioned modules, in each controlling cycle, system operation step is as follows：
Without loss of generality, air knife range correction is GF_delta, GB_delta in front and back, and the air knife distance of saturated pressure is mended
The amount of repaying be delta_gap, air knife is GF_SV apart from setting value in front and back, GB_SV, this control system comprise one in front and back coating deposit
Storage area domain, the historical measurements of thickness of coating before and after storage, CW_bias is that in this memory block, front thickness of coating deducts rear coating thickness
The average of degree.
S1：Before and after reading from first-level machine, whether thickness of coating measurement value information, first determine whether before and after's coating memory area
Full, if less than, thickness of coating is preserved and enters this memory area, enter S4, otherwise, entrance S2.It also can be described as：Read
Forward and backward thickness of coating measured value, if memory area is less than being stored in memory area by institute's Thickness Measurement by Microwave, enter step S4；If storage
Region is full, then enter step S2；
S2：Current thickness of coating measured value is saved into before and after's coating memory area by the principle using first in first out, and
Override earliest thickness of coating measured value in former memory area.Coating deviation average CW_ before and after judging in this memory area
Whether bias exceedes the threshold value of before and after's drift correction, if then entering S3, otherwise enters S4.It also can be described as：Using current
Measured value replace earliest measured value in memory area, then, judge forward and backward coating deviation average CW_ in memory area
Whether bias exceedes the threshold value of before and after's drift correction；If exceeding, enter step S3, if not less than entrance step S4；
S3：For ensure thickness of coating constant, air knife distance should keep constant, that is, before and after air knife apart from knots modification size phase
With, in opposite direction that is to say, that front thickness of coating needs change-CW_bias/2, rear thickness of coating need change CW_bias/2.
Air knife distance, air pressure, line speed with the thickness of coating departure that need to change inputs real-time optimization module respectively, point
Do not calculate before and after's air knife apart from knots modification GF_delta and GB_delta, enter S4.Wherein, real-time optimization module is according to gas
Knife distance, air pressure and line speed calculate thickness of coating predictive value, then control targe adds for thickness of coating predictive value
On the thickness of coating amount that need to change, control deviation is the thickness of coating amount that need to change.According to increment type PID, air knife distance is carried out
Optimizing is so that the thickness of coating value of revised side air knife distance in front and back and air pressure, line speed prediction meets coating
THICKNESS CONTROL desired value.Before and after then, side air knife deducts air knife apart from original value apart from knots modification for revised air knife distance.
It can be briefly described for：Excellent in real time according to air knife distance, air pressure, line speed and thickness of coating departure
Change and calculate optimum air knife distance, so that it is determined that forward and backward air knife is apart from knots modification GF_delta and GB_delta；Wherein, front plating
It is-CW_bias/2 that thickness degree needs the departure changing, and it is CW_bias/2 that rear thickness of coating needs the departure changing；So
Afterwards, enter step S5；
S4：Make GF_delta=0, GB_delta=0, do not carry out before and after's coating drift correction, even forward and backward air knife distance
Knots modification is 0, enters S5.
S5：Judging whether air knife enters zone of saturation, if entering zone of saturation, entering S6, if not entering into saturation region,
Then enter S7.
S6：Increase air pressure and adjust allowance, adjusted according to current air knife distance, air knife height, line speed and increase
Air pressure after section allowance, calculates thickness of coating predictive value by neural network prediction model, calculates predictive value and coating
Deviation between thickness setting value.Adjust the air pressure after allowance, air knife distance and line speed input increasing in fact
When optimization module, calculate air knife apart from knots modification delta_gap, for ensureing that strip steel centrage overlaps with air knife centrage, need
By this air knife at knots modification mean allocation in front and back's side air knife, then GF_delta=GF_delta+delta_gap/2, GB_
Delta=GB_delta+delta_gap/2.Enter S8.
It can be summarized and be described as：
Increase air pressure and adjust allowance, according to current air knife distance, line speed, increase the air knife pressure after allowance
Power, using neural computing thickness of coating predictive value, and then obtains the departure of thickness of coating；
And then, calculated according to the departure real-time optimization of air knife distance, air pressure, line speed and thickness of coating
Optimum air knife distance, determines air knife apart from knots modification, and then this air knife is averagely allocated to forward and backward air knife apart from knots modification carries out
Change, obtain forward and backward air knife apart from knots modification, enter S8；
S7：GF_delta, GB_delta keep constant, and that is, forward and backward air knife keeps constant apart from knots modification, enters S8.
S8：Calculate new air knife in front and back apart from setting value GF_SV=GF_SV+GF_delta, GB_SV=GB_SV+GB_
Delta, and under reach PLC.During air pressure saturation that and if only if, PiniFor air pressure setting value, and under reach PLC.
Technique effect for technique scheme is analyzed as follows：
(1) present invention adopts air knife apart from optimization method in feedback control, effectively overcomes and changes or it because of template
Impact in front and back's thickness of coating of his disturbance it is ensured that in feedback control strip steel front and rear surfaces thickness of coating uniformity.
(2) present invention adopts air knife apart from optimization method in feedback control, effectively overcomes air pressure and is operated in
Saturation region and lead to coating surface quality fluctuation and further adverse effect improved to production capacity it is ensured that the feedforward
Middle strip coating quality.
(3) present invention adopts real-time optimization method in feedback control, meets process requirements in each operating parameter of guarantee
Meanwhile, according to current control parameter and control deviation, calculate air knife in real time apart from knots modification, ensure that thickness of coating meets simultaneously
Control targe, not only ensure that the surface quality of thickness of coating in feedback control, optimizes operating parameter, before and after overcoming simultaneously
Coating deviation, increases air pressure adjustment allowance, remains to ensure that product quality meets index and wants in the case of lifting production line production capacity
Ask.
In sum, using the control system of the present invention, can optimize exactly when in front and back's thickness of coating occurs deviation
Air knife distance, fast and effeciently to eliminate before and after's thickness of coating deviation, thus ensure that the uniformity of thickness of coating, can simultaneously
Effectively ensure that air pressure, away from saturation region, increased the regulation space of air pressure it is ensured that coating surface quality, carrying
Remain in the case of rising production line production capacity ensure that product quality meets index request.
Hereinafter will above-mentioned flow process further be launched to be illustrated, its detailed design can be regarded as this
Bright optional or preferred scheme.For being best understood from following description, provide following table, to each symbol being set forth below, parameter
Amount carries out a kind of definition, and certainly, below table is that one kind is illustrated to enumerate, and respectively meets and also can have other above with parameter amount
Implication, still need to be to be hereafter illustrated as standard.
This control system is mainly by neural network prediction module, real-time optimization module, in front and back coating deviation optimization module, full
Form with four parts such as air pressure optimization modules.
In figure I represent neural network prediction module, be one with strip speed, air knife distance, air pressure for input, plating
Thickness degree is the neural network prediction model that output is set up, and this model learnt based on the historical data of galvanizing process, can be
Line is according to the detected value of current operation operating mode (strip speed S (t), air knife are apart from D (t), air pressure P (t)) to thickness of coating
Make accurate prediction, the nonlinear mapping relation of this neutral net is designated as NNp (*), its expression formula is as follows：
NNp (D (t), S (t), P (t))=CWp (t)
This module is the basis that real-time optimization module runs.
In figure II represents real-time optimization module, and this module is between thickness of coating predictive value and zinc coat thickness control target
Minimum deviation is optimization aim, with air knife apart from technological procedure for constraint, iterative search gives operating mode (air pressure, production
Linear velocity, thickness of coating setting value) under optimum air knife distance.Specifically, what this module solved is an optimization problem, its mesh
Deviation between scalar functions thickness of coating predictive value and control targe, and decision variable is air knife distance, constraints is nerve
Mapping relations between the line speed of neural network forecast module, air knife distance, air pressure and thickness of coating, air knife distance
Technological procedure constrains.Apart from optimizing, eliminate the deviation between thickness of coating predictive value and control targe by air knife.Excellent in real time
Change the basis that module is coating deviation optimization module and saturated pressure optimization module.
In figure III represent before and after coating deviation optimization module, with before and after strip steel thickness of coating uniformity as control targe,
Operating mode shift and lead to before and after's air knife apart from inconsistent when, ensure total thickness of coating up to standard on the premise of, optimize air knife
Distance, with coating deviation before and after eliminating.Specifically, before and after occurring during thickness of coating deviation, in order to ensure total thickness of coating
Do not change, before and after's thickness of coating knots modification will be made in the same size, in opposite direction, correspond, do not change in other operating modes
In the case of change, need to ensure that total air knife distance does not change, and side air knife distance change amount is in the same size in front and back, direction phase
Instead.Operating mode at that time (line speed, air knife distance, air pressure) and need to change thickness of coating input real-time optimization mould
Block, you can the knots modification of air knife distance before and after obtaining respectively.
In figure IV represents saturated pressure optimization module, when air pressure is operated in saturation region, is ensureing thickness of coating
Under the premise of, optimize air knife distance, to adjust the regulation space of air pressure.Specifically, when air pressure is in saturation, give
Determining air pressure increases regulation allowance, then goes out to adjust, by neural computing, the thickness of coating that air pressure is led to
Knots modification, then apart from then compensating the brought thickness of coating of air pressure change, given operating mode, (increase adjusts allowance to air knife
Rear air pressure, air knife distance and line speed) and the thickness of coating that needs of air knife distance put into real-time optimization module, meter
Calculate air knife range correction.
Based on above-mentioned feedforward control system framework, in each controlling cycle, operational flow diagram of the present invention such as Fig. 2 institute
Show, details are as follows for each step of in figure：
S101 (can to it should be understood that step S1 above)：Thickness of coating measurement value information before and after reading from first-level machine,
First determine whether whether before and after's coating memory area is full, if less than, thickness of coating is preserved and enters this memory area, entrance
S104, otherwise, enters S102.
S102 (can to it should be understood that step S2 above)：Current thickness of coating is measured by the principle using first in first out
Value is saved into before and after's coating memory area, and overrides earliest thickness of coating measured value in former memory area.Judge this storage
Before and after in region, whether coating deviation average CW_bias exceedes the threshold value of before and after's drift correction, calculating formula (1)：
If CW_bias>θ _ bias, then enter S103, otherwise enters S104.
S103 (can to it should be understood that step S3 above)：Revise before and after's coating deviation CW_bias, and ensure that coating is thick
Degree is constant, then the relational expression (3) of the mapping relations formula according to neutral net (2) and air knife distance and in front and back's air knife distance
NNp (D (t), P (t), S (t))=CWp (2)
D (t)=D_front (t)+D_back (t) (3)
Understand, when line speed S (t) and air pressure P (t) are constant it is ensured that CWp is constant, then D (t) should keep
Constant, that is, air knife range correction sum is zero in front and back, meets formula (4)
D_front_delta (t)+D_back_delta (t)=0 (4)
Formula (5) is converted into by formula (4),
D_front_delta (t)=- D_back_delta (t) (5)
Before and after i.e., air knife distance change amount, equal in magnitude, in opposite direction.Because thickness of coating deviation is typically little, little
In the range of it is believed that in front and back air knife distance change essentially identical to the gain of unilateral thickness of coating, therefore, thickness of coating is repaiied in front and back
Positive quantity is in the same size, in opposite direction, and to make before and after's coating deviation be changed into 0 it is necessary to allow front air knife distance correction coating inclined
Residual quantity is-CW_bias/2, and the coating departure of rear air knife distance correction is CW_bias/2.
Understand, air knife distance change amount, equal in magnitude in front and back, therefore only needs to calculate the change of front air knife distance according to formula (5)
Change amount can get the variable quantity of rear air knife distance.Respectively using air knife apart from D (t) as Dini, air pressure P (t) is as Pini、
Line speed S (t) is as SiniWith the front thickness of coating departure-CW_bias/2 to be revised as CWm, according to real-time optimization
Algorithm calculates D_front_delta (t).
Real-time optimization algorithm is such description：
Object function：min|CWt-CWp|
Decision variable：D
Constraints：
CWp=NN (D, Pini,Sini) (6)
CWt=NN (Dini,Pini,Sini)+CWm (7)
D∈[Dmin,Dmax] (8)
Optimizing, wherein increasable algorithm description are iterated according to increment type PID algorithm to D：
Error=CWt-CWp (9)
P_error=error-error_1 (10)
I_error=error (11)
D_error=error-2*error_1+error_2 (12)
△ u=Kp*P_error+Ki*I_error+Kd*D_error (13)
D=D+ △ u (14)
Wherein, the initial value of D is Dini, error_1 is the previous generation value in error iterative calculation, and error_2 is error
Upper secondary value in iterative calculation.By formula (9)～formula (14) iterative calculation, find D and make CWp infinite approach CWt.Excellent in real time
Change algorithm and finally return that air knife, apart from knots modification △ D, meets formula (15)
△ D=D-Dini(15)
In above formula, △ D is in the case of current manufacturing lines speed with air pressure, so that thickness of coating is changed needed for CWm
Total air knife is apart from knots modification.Obviously, need exist for adjusting front thickness of coating, therefore this knots modification is all applied to front air knife
Apart from upper, i.e. D_front_delta (t)=△ D；According to formula (5), D_back_delta (t)=- △ D.Enter S105.In order to
Ensure that thickness of coating is constant, air knife distance should keep constant, that is, knife is identical apart from knots modification size in front and back, in opposite direction, so,
D_back_delta (t)=- △ D.This △ D is the departure-CW_bias/2 needing change for front thickness of coating, and-△
D is to need departure CW_bias/2 changing to be modified for rear thickness of coating.
S104 (can to it should be understood that step S4 above)：Make D_front_delta (t)=0, D_back_delta (t)
=0, enter S105.
S105 (can to it should be understood that step S5 above)：Judge whether air pressure enters zone of saturation, if air knife pressure
Power working area has been enter into zone of saturation, then enter S106, otherwise enters S107.
S106 (can to it should be understood that step S6 above)：Make air pressure increase and adjust Pini=P (t)+△ after allowance
P, then optimize air knife distance and change brought thickness of coating variable quantity, the then thickness of coating of required compensation to compensate air pressure
CWm is
CWm=NN (D (t), P (t), S (t))-NN (D (t), Pini,S(t)) (16)
Using D (t) as Dini, S (t) is as Sini, and Pini, CWm input real-time optimization module, calculate air knife distance
Knots modification D_delta.Before and after then, air knife range correction is respectively：
D_front_delta (t)=D_front_delta (t)+D_delta/2 (17)
D_back_delta (t)=D_back_delta (t)+D_delta/2 (18)
Enter S108.
S107 (can to it should be understood that step S7 above)：D_front_delta (t), D_back_delta (t) keep not
Become.Enter S108.
S108 (can to it should be understood that step S8 above)：Before and after calculating, air knife is apart from setting value DF_SV, DB_SV
DF_SV=DF_SV+D_front_delta (t) (19)
DB_SV=DB_SV+D_back_delta (t) (20)
PLC is reached under DF_SV, DB_SV.During air pressure saturation that and if only if, PiniFor air pressure setting value, and under
Reach PLC.
Additionally, every at regular intervals, system online acquisition run in this period produced by new creation data, sieve
Select sample, prediction neural network weight is carried out continue training, update neutral net.Specifically, using back propagation side
Method update neutral net weight, so that prediction neural network is learnt to new work information, can automatically adaptive system spy
The change levied.
Below taking zinc-plated actual production process as a example, the beneficial effect acquired by the present invention is described：
The design sketch using thickness of coating drift correction algorithm before and after the inventive method design is listed in Fig. 3.From figure
In can see, at 1 hour about, thickness of coating deviation statistics value reached the threshold value that air knife distance optimizes before and after startup in front and back
When, before and after coating drift correction algorithm optimization air knife distance so that in front and back coating deviation be under control.Illustrate to adopt the present invention
Described method, can effectively revise before and after's thickness of coating deviation, improve product quality.
The design sketch optimizing using the saturated pressure of present invention design is listed in Fig. 4.From the figure, it can be seen that for gas
Knife pressure has been operated in the situation of saturated pressure edge (67KPa is saturation region), if (time coordinate 30min about) will carry
Rise line speed to improve production capacity, because now air pressure has no adjusted allowance it is impossible to continue to heighten air pressure to eliminate speed
Degree rises the impact (coating is thickening) to thickness of coating, result in the variation of product quality and a large amount of wastes of zinc liquid.And at this
After invention methods described puts into operation (time coordinate be 50min about), air knife distance is optimized in front and back, by ensureing production
Before and after reducing in the case of safety, air knife distance is so that the regulation allowance of air pressure is increased, as illustrated, thickness of coating
Obtain accurately controlling, ensured that the product quality after production capacity lifting.In said process, under traditional control method,
The increase of galvanization production line speed can cause thickness of coating to deviate Product Process index, and quality of coating cannot be guaranteed, i.e. gas
Pressure long-term work hinders the lifting of production line production capacity in zone of saturation, after the method for the invention, by air knife distance
Optimal control it is ensured that the control allowance of air pressure, remain to ensure product quality in the case of lifting production line production capacity
Meet index request.
As fully visible, difference with the prior art of the present invention is：
(1), the present invention adopts neural network model.Compared with traditional regression model, neutral net has very strong non-
Linear fit ability, can more accurately reflect the nonlinear characteristic of zinc-plated production process, with existing employing linear model to plating
The method that zinc production process is controlled is compared, and neural network model can carry out high-precision pre- to the full working scope of zinc-plated production
Survey it is ensured that the present invention's all has good control accuracy and quality under each operating condition of zinc-plated production.
(2), tradition feedback PID needs repeatedly to be controlled according to feedback quantity deviation, due to the measurement of zinc-plated production system
Large time delay so that in front and back the regulation process of thickness of coating deviation slowly, control effect is poor.The present invention with thickness of coating with
Deviation between control targe is target, with the technological procedure of air knife distance for constraint, using neural network prediction model to gas
Knife distance is iterated optimizing, can disposably eliminate the deviation between thickness of coating and control targe, can be fast and accurately
Ground ensures thickness of coating uniformity.
(3), coating deviation optimization method in front and back of the present invention, is traditional based on air pressure, total air knife
Feedback control system supplemented by distance does not have.Specifically, the present invention considers due to operating mode skew or other interference
The problem of coating deviation before and after the strip steel that factor causes, using air knife before and after optimal control side air knife distance it is ensured that
The concordance of strip steel front and rear surfaces thickness of coating, improves Control platform.
(4), saturated pressure optimization method of the present invention, the feedback being traditional does not have.Tool
For body, by the optimal control of air knife distance it is ensured that the control allowance of air pressure, make air pressure close to saturation region when,
Remain to ensure that product quality meets index request in the case of lifting production line production capacity, reduce coating surface quality fluctuation, really
Protect galvanizing production quality.
Claims (5)
1. a kind of zinc-plated production air knife apart from optimal control method it is characterised in that：Comprise the steps：
S1：Read forward and backward thickness of coating measured value, if memory area is less than being stored in memory area by institute's Thickness Measurement by Microwave, enter step
Rapid S4；If memory area is full, enter step S2；
S2：Replace earliest measured value in memory area using current measured value, then, judge forward and backward plating in memory area
Whether layer deviation average CW_bias exceedes the threshold value of before and after's drift correction；If exceeding, enter step S3, if not less than entering
Enter step S4；
S3：Optimum air knife is calculated according to air knife distance, air pressure, line speed and thickness of coating departure real-time optimization
Distance, so that it is determined that forward and backward air knife is apart from knots modification GF_delta and GB_delta；Wherein, front thickness of coating needs change
Departure is-CW_bias/2, and it is CW_bias/2 that rear thickness of coating needs the departure changing；Then, enter step S5；
S4：Make forward and backward air knife be 0 apart from knots modification, enter step S5；
S5：Judging whether air pressure enters zone of saturation, if entering, entering step S6, if being introduced into, entering step
S7；
S6：Increase air pressure and adjust allowance, according to current air knife distance, line speed, increase the air pressure after allowance,
Using neural computing thickness of coating predictive value, and then obtain the departure of thickness of coating；
And then, optimum is calculated according to the departure real-time optimization of air knife distance, air pressure, line speed and thickness of coating
Air knife distance, determines air knife apart from knots modification, and then this air knife is averagely allocated to forward and backward air knife apart from knots modification is changed
Become, obtain forward and backward air knife apart from knots modification, enter step S8；
S7：Forward and backward air knife keeps constant apart from knots modification, enters S8；
S8：The forward and backward air knife confirming according to step S3 and S6 determines new forward and backward air knife apart from setting value apart from knots modification, according to
It is air pressure setting value according to the air pressure that step S6 increases allowance.
2. as claimed in claim 1 zinc-plated production air knife apart from optimal control method it is characterised in that：In described step S6
In, when using neural computing thickness of coating predictive value, obtain thickness of coating further with neural network prediction module
Predictive value；
Described neural network prediction module with strip speed, air knife distance, air pressure for input, built by output by thickness of coating
Vertical, and it is learnt based on the historical data of galvanizing process, so the strip speed according to current operation, air knife distance and
The sampled value of air pressure is predicted to thickness of coating.
3. as claimed in claim 2 zinc-plated production air knife apart from optimal control method it is characterised in that：In described step S6
In, the thickness of coating of required compensation is：
CWm=NN (D (t), P (t), S (t))-NN (D (t), Pini,S(t))
Wherein, D (t) is the air knife distance of t, and P (t) is the air pressure of t, and S (t) is the line speed of t；
PiniIt is to increase the air pressure after allowance.
4. as claimed in claim 1 zinc-plated production air knife apart from optimal control method it is characterised in that：In described step S3
And/or in S6, optimize calculate optimum air knife apart from when, calculate optimum air knife distance using real-time optimization module optimization；
Described real-time optimization module with the minimum deviation between thickness of coating predictive value and control targe as target, with air knife away from
It is constraint from traffic coverage, optimum gas under air pressure, line speed and thickness of coating setting value that iterative search gives
Knife distance.
5. as claimed in claim 4 zinc-plated production air knife apart from optimal control method it is characterised in that：Described real-time optimization mould
The real-time optimization algorithm that block is adopted is specifically described as：
Object function：min|CWt-CWp|
Decision variable：D
Constraints：
CWp=NN (D, Pini,Sini) (6)
CWt=NN (Dini,Pini,Sini)+CWm (7)
D∈[Dmin,Dmax] (8)
Optimizing, wherein increasable algorithm description are iterated according to increment type PID algorithm to D：
Error=CWt-CWp (9)
P_error=error-error_1 (10)
I_error=error (11)
D_error=error-2*error_1+error_2 (12)
△ u=Kp*P_error+Ki*I_error+Kd*D_error (13)
D=D+ △ u (14)
Wherein, the initial value of D is Dini, error_1 is the previous generation value in error iterative calculation, and error_2 is error iteration
Upper secondary value in calculating；By formula (9)～formula (14) iterative calculation, find D and make CWp infinite approach CWt；Real-time optimization is calculated
Method finally returns that air knife, apart from knots modification △ D, meets formula (15)
△ D=D-Dini(15)
In above formula, △ D is in the case of current manufacturing lines speed with air pressure, makes thickness of coating change the total gas needed for CWm
Knife apart from knots modification, this △ D be for front thickness of coating need change departure-CW_bias/2, and-△ D be directed to after
Thickness of coating needs departure CW_bias/2 changing to be modified.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610650208.7A CN106435427B (en) | 2016-08-08 | 2016-08-08 | Zinc-plated production air knife is apart from optimal control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610650208.7A CN106435427B (en) | 2016-08-08 | 2016-08-08 | Zinc-plated production air knife is apart from optimal control method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106435427A true CN106435427A (en) | 2017-02-22 |
| CN106435427B CN106435427B (en) | 2018-10-02 |
Family
ID=58184345
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610650208.7A Active CN106435427B (en) | 2016-08-08 | 2016-08-08 | Zinc-plated production air knife is apart from optimal control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106435427B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107794481A (en) * | 2017-10-20 | 2018-03-13 | 甘肃酒钢集团宏兴钢铁股份有限公司 | A kind of stair like control strategy method of galvanized wire air knife position |
| CN113667918A (en) * | 2021-07-27 | 2021-11-19 | 首钢京唐钢铁联合有限责任公司 | Control method for switching thickness of hot-dip galvanized strip steel coating |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20110109274A (en) * | 2010-03-31 | 2011-10-06 | 현대제철 주식회사 | Hot coil for galva annealed steel sheet and method for producing galva annealed steel sheet by using hot coil |
| CN102912275A (en) * | 2012-10-23 | 2013-02-06 | 鞍钢股份有限公司 | Automatic control system for plating thickness of hot galvanizing line |
| CN103695830A (en) * | 2013-12-20 | 2014-04-02 | 鞍钢股份有限公司 | Coating thickness control method in hot galvanizing production process |
| CN104846306A (en) * | 2015-05-07 | 2015-08-19 | 浙江中控研究院有限公司 | Zincing thickness control system and method |
| CN105525248A (en) * | 2015-11-30 | 2016-04-27 | 浙江中控研究院有限公司 | Method for plating thickness feedforward optimal control of galvanization production line |
-
2016
- 2016-08-08 CN CN201610650208.7A patent/CN106435427B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20110109274A (en) * | 2010-03-31 | 2011-10-06 | 현대제철 주식회사 | Hot coil for galva annealed steel sheet and method for producing galva annealed steel sheet by using hot coil |
| CN102912275A (en) * | 2012-10-23 | 2013-02-06 | 鞍钢股份有限公司 | Automatic control system for plating thickness of hot galvanizing line |
| CN103695830A (en) * | 2013-12-20 | 2014-04-02 | 鞍钢股份有限公司 | Coating thickness control method in hot galvanizing production process |
| CN104846306A (en) * | 2015-05-07 | 2015-08-19 | 浙江中控研究院有限公司 | Zincing thickness control system and method |
| CN105525248A (en) * | 2015-11-30 | 2016-04-27 | 浙江中控研究院有限公司 | Method for plating thickness feedforward optimal control of galvanization production line |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107794481A (en) * | 2017-10-20 | 2018-03-13 | 甘肃酒钢集团宏兴钢铁股份有限公司 | A kind of stair like control strategy method of galvanized wire air knife position |
| CN113667918A (en) * | 2021-07-27 | 2021-11-19 | 首钢京唐钢铁联合有限责任公司 | Control method for switching thickness of hot-dip galvanized strip steel coating |
| CN113667918B (en) * | 2021-07-27 | 2023-08-15 | 首钢京唐钢铁联合有限责任公司 | Control method for thickness switching of hot dip galvanized strip steel coating |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106435427B (en) | 2018-10-02 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104846306B (en) | A kind of Zinc Coating Thickness control system and method | |
| CN105525248B (en) | A kind of galvanization production line thickness of coating feedforward optimal control method | |
| CN103205665B (en) | An automatic control method for zinc layer thickness in a continuous hot galvanizing zinc line | |
| CN105316613B (en) | A kind of zinc coating thickness control method and system based on time_varying delay offset correction technology | |
| CN106637026B (en) | A kind of galvanizing process air pressure method for real-time optimization control and system | |
| CN106249724B (en) | A kind of polynary molten steel quality forecast Control Algorithm of blast furnace and system | |
| CN101457264B (en) | Blast furnace temperature optimization control method | |
| CN106773682B (en) | The glass furnace bottom of pond temperature intelligent forecast Control Algorithm being dynamically determined based on time lag | |
| CN106167887B (en) | Hot dip galvanizing coating thickness fast switch over method and system away from dynamic compensation based on knife | |
| CN103469137A (en) | Preset control method for thickness flying gauge change of hot-dip zinc coating | |
| CN108845501A (en) | A kind of blast-melted quality adaptation optimal control method based on Lazy learning | |
| CN106435427B (en) | Zinc-plated production air knife is apart from optimal control method | |
| CN106868440B (en) | Method for predicting and adjusting thickness of strip steel continuous hot-dip galvanized coating | |
| KR101722405B1 (en) | Method and apparatus for controlling acid concentration for pickling in cold rolling | |
| CN110295338A (en) | A kind of stable strip enters the control method of zinc pot temperature | |
| CN110607435A (en) | Annealing furnace plate temperature control system and method | |
| CN103510032B (en) | The deviate control method of cold rolling hot dip galvanizing plating uniformity | |
| CN107130199B (en) | A kind of continuous hot galvanizing air knife knife is away from autocontrol method | |
| CN109240203B (en) | Multi-model-based continuous casting billet constant weight control method | |
| CN102873106B (en) | Quick and precise elongation control method for temper mill | |
| CN109763085A (en) | A kind of temperature controlled method of hot galvanizing line alloying section | |
| CN107016509B (en) | A method of reducing steel rolling process energy consumption per ton steel | |
| CN105568197A (en) | Method for accurately controlling weight of continuously-hot-galvanized zinc layer | |
| Edwards et al. | Coating mass control system design for a continuous galvanizing line | |
| CN104259219A (en) | Rolling method of hot rolling strip steel narrow interval width control |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |