The specific embodiment
Fig. 1 is the structural representation of the utility model one embodiment, and five frames of five frame cold continuous rollings are six-high cluster mill all, and the numeral 1~5 above the frame is represented frame respectively 1~No. 5, and rolling direction from left to right.Because the plant equipment of each frame all is the same, form with the equipment that No. 3 frames are example explanation five frame connection rolling machine: No. 3 frames by last backing roll 6, go up intermediate calender rolls 7, top working roll 8, bottom working roll 9, intermediate calender rolls 10, following backing roll 11 are formed down.In addition, jockey pulley 12 is equipped with in the tandem mill porch, coiling machine 13 is equipped with in the exit; Rolling mill transmission system is the intermediate calender rolls transmission; Intermediate calender rolls uses frequency control motor 14,15 to carry out speed governing up and down; Motor is driven by frequency converter 16, and programmable logic controller (PLC) (PLC) 17 is issued frequency converter with the speed regulation amount, and frequency converter is regulated motor speed makes the live-roller linear velocity reach setting value; Milling train uses press down system 18 control roll gap; The control principle is that THICKNESS CONTROL (AGC) is accomplished through regulating the milling train transmission speed, and tension force is then accomplished through regulating roll gap between frame.Instrumentation comprises 4 cover X-ray thickness gauges, 3 cover laser velocimeters, some cover pulse coders (pulse coder all is housed) altogether on all bunchers.Wherein 4 cover X-ray thickness gauges are respectively frame inlet calibrator 19,1 frame outlet calibrator 20,5 frames inlet calibrator 21,5 frames outlet calibrator 22 No. 1; 3 cover laser velocimeters are respectively 1 frame outlet tachymeter, 23,4 frames outlet tachymeter, 24,5 frames outlet tachymeter 25; Because inlet jockey pulley place does not exist advancing sliply, on the inlet jockey pulley, pulse coder 26 is installed and promptly can be accurately obtained 1 frame strip steel at entry linear velocity in addition, such 1 frame porch need not dispose laser velocimeter.According to such instrument configuration; No. 1 and No. 5 frames can be used second flow quantity AGC and the AGC control of keeping watch on the AGC coupling; But because two frames in tandem mill end have three kinds of control models according to the specification difference of rolled band steel; Be respectively Mode A, B and C, correspond respectively to thicker softer band steel, the band steel of intermediate gauge, thin harder band steel, the implementation method of keeping watch on AGC has some differences.For example following No. 5 frames of C pattern are as smooth frame, and the exit thickness of 5 frames is not controlled, and need on preceding 4 frames, accomplish the adjusting of band steel exports thickness, and the calculating of controlled quentity controlled variable and objective for implementation are with different under other pattern like this; The control method of tension force also has certain difference under A pattern and the B pattern.Because the supervision AGC method after diversity 5 frames of pattern is not suitable for explaining the thought of this method; Therefore present embodiment is that example is done an explanation with the supervision AGC method of No. 1 frame; Supervision AGC control thought after 5 frames is the same, and just implementation method has some differences.
This AGC method may further comprise the steps:
1. calculate the band steel exports thickness h at current time outlet calibrator place
Exc, ethg:
In the operation of rolling, enabled simultaneously under the situation of second flow quantity AGC and supervision AGC, precomputation obtains being with the steel exports one-tenth-value thickness 1/10 according to second flow amount equation, should value transfer to outlet calibrator place from the inlet calibrator through two synchronous transfer models, is specially:
(1) according to second flow amount equation precomputation band steel exports one-tenth-value thickness 1/10:
No. 1 the milling train porch is equipped with calibrator can record band steel inlet thickness; Be equipped with pulse coder on the inlet jockey pulley; Advancing slip owing to not existing at the jockey pulley place, therefore can be with the jockey pulley linear velocity as band steel entrance velocity, 1 frame exit is equipped with laser velocimeter can obtain being with steel exports speed; According to the measured value that these instrumentations obtain, use exit thickness precomputation device 27 to calculate band steel exports thickness h with following formula
Ex, calc:
In the formula, h
Ex, calcExit thickness for the calculating of second flow amount equation; V
EnFor band steel entrance velocity actual value, measure by pulse coder on the inlet jockey pulley; V
ExFor band steel exports speed actual value, measure by the outlet laser velocimeter; h
EnFor band steel inlet thickness actual value, measure by the inlet calibrator.
(2) use the first synchronous transfer model to obtain being transferred to the exit thickness value h at roll gap place
Exc, gap:
Use the first synchronous transfer model, with the h that calculates
Ex, calcFrom inlet calibrator synchronous transfer to 1 frame roll gap place, obtain the exit thickness value h at current time roll gap place with band steel entrance velocity
Exc, gap, that is:
h
exc,gap=TPM1(h
ex,calc)
(3) use the second synchronous transfer model to obtain being transferred to the exit thickness value h at outlet calibrator place
Exc, ethg:
Use the second synchronous transfer model, with the exit thickness value h at roll gap place
Exc, gapWith band steel exports speed from the roll gap synchronous transfer to exporting the calibrator place, obtain the exit thickness value h at current time outlet calibrator place
Exc, ethg, that is:
h
exc,ethg=TPM2(h
exc,gap)。
The utility model adopts unique synchronous transfer model, and the program flow diagram of synchronous transfer model TPM is as shown in Figure 2, and each synchronous transfer model structure is identical.Present embodiment is that example describes with the first synchronous transfer model, and the first synchronous transfer model is made up of first to the 3rd shift register and judge module, and each shift register can store several real variable.At first transmission range is divided into several sections, notices that the segmentation number do not fix, but by the strip speed decision, the length of each section is: L
S=V * T
S, L in the formula
SBe every section length, V is a transmission speed, T
SBe the sampling time; T
sBe fixed value, look the setting of PLC controller and decide T in the present embodiment
s=4ms.
The belt steel thickness sampled value of first shift register storage input, every through a sampling time T
sThe data of all storages are moved one, first position of then the belt steel thickness sampled value of current time being deposited this register successively backward;
The length of the second shift register memory segment whenever moves one with the data of all storages through a sampling time successively backward, then the section length of current time is stored in first position of this register;
The 3rd shift register is stored the distance that corresponding belt steel thickness sampled value is passed by, and all section length additions that are about to the corresponding times prior of second shift register obtain, and for example k element of the 3rd shift register is:
In the formula, B2 and B3 represent the second and the 3rd shift register respectively.
Whenever, through a sampling instant distance value of all storages is moved one successively backward, then the section length of current time is stored in first position of this register, promptly first element of the second and the 3rd shift register is always equal; Three registers are corresponding one by one;
Judge module be used for each sampling time judge one the order three shift registers whether the element more than or equal to transmission range L is arranged; If i element value more than or equal to transmission range i-1 element value less than transmission range; Represent that i element in first shift register transmitted the given transmission distance, then with i element value output in first shift register;
Note need being provided with in advance the maximum memory space N of register here, if strip speed is very slow, the length of each segmentation is all especially little, and the register overflow fault will take place for N section length and also do not reach the transmission range L of setting.Therefore in this mode, memory space N=500 is set, each sampling instant all can be judged section length L
SWhether less than minimum section length L
Min=L/500, and if less than minimum section length three register of this sampling instant do not upgrade, and only with section length summation, judge section length in next sampling instant then with value whether more than or equal to minimum section length; Just carry out the renewal of three shift registers up to section length more than or equal to minimum section length with value.So just guaranteed that shift register overflow fault can not take place.
2. obtain and keep watch on AGC adaptive equalization factor F
Comp:
According to band steel exports speed, export thick poor, whether be in the adaptively selected supervision of this Several Factors of acceleration and deceleration stage AGC compensating factor, be specially:
(1) according to 1 frame muzzle velocity actual value access speed factor F
V, more greatly then velocity factor is more little for muzzle velocity, and the velocity factor value is between 0.7~1.0.
(2) choose thickness factor F according to the exit thickness difference
h, more greatly then the thickness factor is big more to export thick difference, and thickness factor value is between 0.6~1.0.
(3) whether basis is in acceleration and deceleration stage selection acceleration factor F
aIf, be not in the acceleration and deceleration stage, then acceleration factor is taken as 1.0; If be in the acceleration and deceleration stage, then need improve acceleration factor, can be taken as 1.2;
(4) keep watch on AGC adaptive equalization factor F with computes
Comp:
F
comp=F
V×F
h×F
a
3. obtain and keep watch on the average ramp value of AGC exit thickness error
At first try to achieve the supervision thickness error E of exit thickness
Mon, ask for this error then at the mean value of keeping watch on the section, step appears in order to prevent controlled quentity controlled variable, at last also in addition the slope handle and obtain keeping watch on the average ramp value of AGC exit thickness error
Be specially:
(1) keeps watch on thickness error E with the computes current time
Mon:
E
mon(n)=(h
ex,thg-h
exc,ethg)×F
comp-E
tpm(n-1) n>1;
E
mon(n)=(h
ex,thg-h
exc,ethg)×F
comp?n=1;
In the formula, h
Ex, thgBe outlet calibrator measured value; E
Tpm(n-1) keep watch on the exit thickness influence value that the AGC controlled quentity controlled variable causes current time constantly for last one; N representes current time; Can the exit thickness in this moment be impacted after regulating because last one constantly keeps watch on AGC, therefore moment of the supervision AGC controlled quentity controlled variable of calculating current time must be earlier with on one control the influence value that causes constantly and deduct.If current time is an initial time, the supervision AGC controlled quentity controlled variable that goes up a moment so is 0, so its influence value also is 0.
(2) use the consecutive mean module to ask for E
MonAt the mean value of keeping watch on the section
Flow chart is as shown in Figure 3:
Keeping watch on AGC is to be used to compensate the trend (thin or thick partially partially) that comparatively long-term process changes the thick difference of outlet that causes, and therefore need ask for E to whole supervisions section (promptly from the frame roll gap to exporting this segment distance of calibrator)
MonMean value, the error that interference more at random causes can be cancelled out each other.
Use consecutive mean module MAV to ask for E
MonAt the mean value of keeping watch on the section
That is:
The consecutive mean module is made up of the 4th to the 6th shift register and judging treatmenting module, will the section of monitoring (promptly from the frame roll gap to exporting this segment distance of calibrator) be divided into plurality of sections, segments is determined that by strip speed every section length is L
S=V * T
S, L in the formula
SBe every section length, V is band steel transmission speed, T
SBe the sampling time;
The 4th shift register storage input variable E
MonSampled value, every through a sampling time T
SThe value of all storages in the register is moved one successively backward, then the sampled value of current time input variable is deposited in first position of this register;
The 5th shift register is used for storing the weights of input variable sampled value, and weights determine that by strip speed the weights of each input variable are W
X=V * T
S/ L
Mon, in the formula, L
MonFor keeping watch on the length of section; Whenever, the weights of all storages in the register are moved one successively backward through a sampling time, then the weights of current time input variable are deposited in first position of this register;
The weights that the 6th shift register is used for storing the input variable sampled value with, all weights additions that are about to corresponding times prior in the 5th shift register obtain, for example k element in the 6th shift register is:
In the formula, B5 and B6 represent the 5th and the 6th shift register respectively.
Each sampling instant is with the weights of all storages and move one backward successively, then the weights of current time input variable is stored in first position of this register, and promptly first element of the 6th shift register and the 5th shift register always equates.Three registers are corresponding one by one;
Judging treatmenting module is used for each sampling time and judges that the element more than or equal to 1.0 appears in the 6th shift register at first; If i element more than or equal to 1.0 i-1 element less than 1.0; Then i element of the 5th shift register deducted that i element surpasses 1.0 amount in the 6th shift register, with preceding i element guaranteeing the 5th shift register and be 1.0 just in time; Then preceding i element of the 4th shift register multiply by preceding i element value of corresponding the 5th shift register, i.e. each input variable E constantly
MonMultiply by its corresponding weights and sue for peace and just obtained input variable E
MonAt the mean value of keeping watch on the segment length
That is:
In the formula, B4 and B5 represent the 4th and the 5th shift register respectively.
Note need being provided with in advance the maximum memory space C of register here, if strip speed is very slow, the weights of each segmentation are all especially little, and the register overflow fault will take place for C weights and also do not reach 1.0.Therefore in this consecutive mean module, memory space C=100 is set, each sampling instant all can be judged current time weights W
XWhether more than or equal to minimum weights W
Min=1.0/C, and if less than minimum weights three shift register of this sampling instant all do not upgrade, and only with weights summations, judge weights and whether more than or equal to minimum weights in next sampling instant then; Just carry out the renewal of three shift registers more than or equal to minimum weights up to weights and value.
(3) monitor the use of exit ramp generator to generate the average thickness error
slope value
Calculate the controlled quentity controlled variable of keeping watch on AGC owing to need to use
; In general; Avoid AGC controlled quentity controlled variable generation step to change; Can bring bigger impact to the executing agency of controller like this; Therefore used ramp value
that ramp generator RGE (RampGenerator) produces the thick poor mean value of outlet here like this when the variable generation step variation of input; Step can not take place and change in the output valve of ramp generator, but the slope arrives the input variable value.
Ramp generator is calculated as follows ramp value:
In the formula, Y
Ramp(n) be current time ramp generator output valve, Y
Ramp(n-1) be a last moment ramp generator output valve, T
SBe the sampling time, T
ABe the slope time, through regulating T
AThe speed degree of control ramp, T
AMore greatly then ramp must be slow more, T
AMore little then ramp must be fast more.
Use ramp generator to produce and keep watch on the average ramp value of exit thickness error
promptly:
Like this as
when changing;
becomes new value at once, reaches new value but each sampling instant changes
up to
.
4. obtain second flow amount calculated thickness error correction values Δ h
MFCKeep watch on the influence value E that AGC controls with current time
Tpm(n):
At first with the average ramp value of thickness error
Action delay through first first-order lag link compensation executing agency promptly obtains a second flow quantity AGC thickness error correction value Δ h
MFCUse the 3rd synchronous transfer model and the second first-order lag link to ask for the influence value E that current time is kept watch on AGC then
Tpm(n), be specially:
(1) compensate the action delay that AGC controls executing agency through the first first-order lag link:
Need compensate the action delay of AGC control executing agency in the time of error of calculation correction value, represent AGC control executing agency with a first-order lag link PT1 here, the PT1 link algorithm of discretization is:
In the formula, Y
Pt1(n) be the output valve of PT1 link current time; Y
Pt1(n-1) be the output valve in a moment on the PT1 link; T
SBe the sampling time of PLC controller; T
DBeing PT1 link time constant, being taken as the rise time of AGC control executing agency here, because tandem mill AGC carries out through regulating transmission speed, is the rise time of speed regulating mechanism so here; X
nFor the current time input value, here be
The value of current time; X
N-1For
The value in a last moment.
Will
Through the rise time of the first first-order lag link compensation speed governor motion, obtain the thickness error correction amount h of second flow quantity AGC
MFC, that is:
Subscript SA representes speed regulating mechanism in the formula.
Calculate and keep watch on the correction thickness error Δ h of AGC flow quantity AGC second
MFCAfter, with Δ h
MFCDirectly be added to the second flow amount and calculate outlet one-tenth-value thickness 1/10 h
Ex, calcGet on, just obtain calculating the outlet one-tenth-value thickness 1/10,, can further improve the control accuracy of second flow quantity AGC like this according to the controlled quentity controlled variable of revised exit thickness value calculating second flow quantity AGC through keeping watch on the revised second flow amount of AGC.
(2) use the 3rd synchronous transfer model with Δ h
MFCValue transfers to outlet calibrator place from roll gap, obtains Δ h
MFC, ethg, the 3rd synchronous transfer model is identical with the first synchronous transfer model structure.
Notice that calculating is to use the thickness data at outlet calibrator place to calculate when keeping watch on the AGC error amount; Therefore when influencing of causing controlled in the supervision of calculating current time; Need to use the 3rd synchronous transfer model 34 that the second flow amount error correction values at roll gap place is transferred to outlet calibrator place, this model is with the Δ h that calculates
MFCWith band steel exports speed from the roll gap synchronous transfer to exporting the calibrator place, that is:
Δh
MFC,ethg=TPM3(Δh
MFC)
(3) delay time through the detection of second first-order lag link compensation outlet calibrator;
Feed the 3rd first-order lag link with transferring to flow quantity AGC thickness error correction value second that the outlet calibrator goes out, the detection time-delay of compensation outlet calibrator, the time constant of the 3rd first-order lag link detects delay time for the outlet calibrator.Finally obtain current time and keep watch on the AGC controlled quentity controlled variable next influence value E that causes constantly
Tpm(n), that is:
E
tpm(n)=PT1
ethg(Δh
MFC,ethg)
In the formula, subscript ethg representes to export calibrator; The influence value E of current time
Tpm(n) supply n+1 to use constantly after calculating.
5. obtain the live-roller linear velocity regulated quantity Δ V that keeps watch on AGC
R, mon:
According to keeping watch on the average ramp value of AGC exit thickness error
Calculate needed muzzle velocity regulated quantity Δ V
Mon, obtain 1 frame live-roller linear velocity regulated quantity Δ V according to the advancing slip factor and roller footpath calculation of parameter again
R, mon, be specially:
(1) with the needed 1 frame muzzle velocity regulated quantity Δ V of computes
Mon:
In the formula, h
Ex, setBe band steel exports thickness setting value, by process computer according to rolling procedure making.
(2) with the regulated quantity Δ V of computes 1 frame live-roller linear velocity
R, mon:
In the formula, F
SlBe the advancing slip factor of 1 frame, general value is between 0.03~0.5; R
dFor the roller of live-roller and working roll directly than, be the intermediate calender rolls transmission in this example, therefore be exactly the ratio of intermediate calender rolls here with working roll roller footpath.
Through above-mentioned steps, finally obtain second flow amount calculated thickness error correction values Δ h
MFCWith the transmission speed regulated quantity Δ V that keeps watch on AGC
R, mon, the second flow amount error correction values of trying to achieve is delivered to a second flow quantity AGC program, and the transmission speed regulated quantity is delivered to frequency converter remove to regulate the frame driving motor, just accomplished this supervision AGC and regulated.
It is as shown in Figure 4 that the high accuracy belt steel rolling is kept watch on automatic thickness control system, and programming realizes that it comprises on PLC:
Exit thickness precomputation device 27 is used for calculating band steel exports thickness in band steel porch according to second flow amount equation:
In the formula, h
Ex, calcExit thickness for the calculating of second flow amount equation; V
EnFor band steel entrance velocity actual value, measure by pulse coder on the inlet jockey pulley; V
ExFor band steel exports speed actual value, measure by the outlet laser velocimeter; h
EnFor band steel inlet thickness actual value, measure by the inlet calibrator;
The first synchronous transfer model 28 is used for h
Ex, calcDevice with band steel entrance velocity synchronous transfer to mill roll-gap place obtains mill roll-gap place precomputation thickness h
Exc, gap
The second synchronous transfer model 29 is used for the precomputation thickness h with the roll gap place
Exc, gapTransfer to outlet calibrator place with band steel exports speed synchronization, obtain exporting the precomputation exit thickness h at calibrator place
Exc, ethg
Adaptive equalization device 30 is used for, gantry speed poor according to exit thickness, acceleration is asked for and kept watch on AGC adaptive equalization factor F
Comp, this device utilizes following formula to calculate:
F
comp=F
V×F
h×F
a
In the formula, F
VBe the muzzle velocity factor; F
hFor exporting the thick poor factor; F
aBe acceleration factor;
Be compensated factor F
CompAfter, keep watch on thickness error E with the computes current time
Mon:
E
mon(n)=(h
ex,thg-h
exc,ethg)×F
comp-E
tpm(n-1) n>1;
E
mon(n)=(h
ex,thg-h
exc,ethg)×F
comp n=1;
In the formula, h
Ex, thgBe outlet calibrator measured value; E
Tpm(n-1) keep watch on the exit thickness influence value that the AGC controlled quentity controlled variable causes current time constantly for last one; N representes current time; Can the exit thickness in this moment be impacted after regulating because last one constantly keeps watch on AGC, therefore moment of the supervision AGC controlled quentity controlled variable of calculating current time must be earlier with on one control the influence value that causes constantly and deduct.If current time is an initial time, the supervision AGC controlled quentity controlled variable that goes up a moment so is 0, so its influence value also is 0.
Consecutive mean module 31 is used to ask for supervision thickness error E
MonAt the mean value of keeping watch on the section
Second flow amount calculated thickness error correction device is used to calculate the exit thickness error correction values that the second flow amount is calculated, and comprises the ramp generator 32 and the first first-order lag device 33; Ramp generator 32 is used for calculating
Ramp value
The rise time that the first first-order lag device 33 is used for the compensation speed governor motion obtains second flow amount calculated thickness round-off error Δ h
MFC
The 3rd synchronous transfer model 34 is used for Δ h
MFCObtain exporting the thickness round-off error Δ h at calibrator place to outlet calibrator place from the roll gap synchronous transfer
MFC, ethg
The second first-order lag device 35 is used to compensate the sampling time-delay that exports calibrator and obtains current time monitoring AGC controlled quentity controlled variable to next exit thickness influence value E that causes constantly
Tpm(n);
Keep watch on the AGC adjusting device, be used for calculating and keep watch on the AGC controlled quentity controlled variable, comprise band steel exports speed adjusting device 36 and live-roller speed adjusting device 37; Band steel exports speed adjusting device is used for basis
Calculate band steel exports speed regulation amount Δ V
MonThe live-roller speed adjusting device is used for according to band steel exports speed regulation amount Δ V
MonCalculate live-roller linear velocity regulated quantity Δ V
R, mon
The first synchronous transfer model 28, the second synchronous transfer model 29, consecutive mean module 31, the first first-order lag device 33, the 3rd synchronous transfer model 34, the second first-order lag device 35 are corresponding with the first synchronous transfer model, the second synchronous transfer model, consecutive mean module, the first first-order lag device, the 3rd synchronous transfer model, the second first-order lag device that the high accuracy belt steel rolling is kept watch in the automatic thickness control method respectively.
More than combine embodiment that the utility model has been done concrete description, but not as the qualification of the utility model, all modifications and variations in the utility model claim scope all drop within the protection domain that receives the utility model.