An optimization method for rolling mixed thickness control function of cold-rolled high-grade silicon steel

Abstract

The application discloses a kind of optimization methods of cold-rolled high-grade silicon steel rolling mixed thickness control function, belong to high-grade silicon steel rolling technical field.The application includes the following steps: S1, tension adjusting roll gap influences mixed thickness control;S2, automatically determine steel material by PLC system;S3, automatically determine rolling pass by PLC system;S4, set gain coefficient;S5, exclude abnormal interference factors.The application can distinguish high-grade steel and end rolling pass by PLC system and match different parameters for adjustment, using the application can solve the problem of thickness abnormal fluctuation caused by tension or other factors when high-grade steel and end pass are rolled, reduce silicon steel finished product quality defects, improve yield, and can shorten the fault time caused by tension meter hardware failure, improve enterprise technical level.

Description

Technical Field

[0001] This invention relates to the field of high-grade silicon steel rolling technology, specifically to an optimization method for controlling the mixed thickness function in cold-rolled high-grade silicon steel rolling. Background Technology

[0002] In the production of high-grade silicon steel, when the number of passes or the silicon content of the product changes, the thickness deviation may exceed the target value. Since the thickness precision control of high-grade silicon steel is very difficult, abnormal deviations during the rolling process are often improved by manual adjustment. However, relying on experience to manually adjust the rolling parameters cannot effectively eliminate abnormal thickness deviations of high-grade silicon steel. In severe cases, the ineffective manual adjustment may cause the rolling process to stop, resulting in huge direct and indirect economic losses.

[0003] To control thickness deviation during the rolling of high-grade silicon steel, single-stand rolling mills without a flow rate thickness control function often employ a hybrid thickness control function to better eliminate thickness deviation, in addition to traditional thickness control functions (such as feedforward, feedback thickness control, tension thickness control, Smith control, BISRA control, etc.). This hybrid thickness control function can simultaneously adjust tension, speed, and roll gap. When thickness deviation occurs, it uses PI regulation to apply the tension adjustment to the roll gap and decouples the thickness deviation in reverse, converting it into a speed change at the mill inlet for adjustment. However, the gain function and proportional coefficient of the hybrid thickness control function are fixed and cannot be adjusted according to changes in material type or rolling pass. Therefore, when rolling high-grade silicon steel, especially in the last pass, the thickness control accuracy may still be low. Summary of the Invention

[0004] The purpose of this invention is to provide an optimization method for controlling the mixed thickness of cold-rolled high-grade silicon steel. By using a PLC system to identify the high-grade steel and the last rolling pass and adjusting different parameters, the problem mentioned in the background art is solved.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] An optimization method for controlling the mixed thickness in cold-rolled high-grade silicon steel rolling includes the following steps:

[0007] S1. Tension adjustment roller gap affects the control of mixing thickness;

[0008] S2. The steel type and material are automatically determined by the PLC system;

[0009] S3. The rolling pass is automatically determined by the PLC system;

[0010] S4. Set the gain coefficient;

[0011] S5. Eliminate abnormal interference factors.

[0012] Preferably, the influence of the tension regulating roller gap on the mixing thickness control in S1 includes the following steps:

[0013] S11. When the rolling pass and speed reach the set requirements, the mixed thickness control function is activated. The tension on the mill inlet side is controlled by the roll gap and adjusted using the inlet side tension signal and the PI controller of the roll gap position.

[0014] S12, Formula for calculating tension adjusting roller gap:

[0015] ΔS=-C GATRP ×(T RENT -T FBENT )-∫g GATR ×C GATRI ×(T RENT -T FBENT )dt

[0016] in,

[0017] ΔS----Tension regulating roller gap component

[0018] T RENT ----Tension setting at the mill inlet

[0019] T FBENT ----Tension feedback at the mill inlet

[0020] C GATRP ----Roll gap ATR proportional gain

[0021] C GATRI ----Integral gain of roll gap ATR

[0022] g GATR ----Integral time constant, fixed period

[0023] According to the calculation formula, the difference between the inlet tension setting and the feedback is used to obtain the adjustment amount of the roll gap through proportional-integral adjustment, which ultimately affects the adjustment of the mill roll gap.

[0024] Preferably, the automatic determination of steel type and material by the PLC system in S2 includes the following steps:

[0025] S21. The secondary system assigns a material code to the rolled steel grade. Before the current steel grade is rolled, the material code is sent to the primary PLC along with other steel grade information via electronic message. The PLC system collects the material code of the rolled steel grade in real time and makes a judgment.

[0026] S22. Let 1 ≤ M SET ≤M ULDetermine a specific M position according to process requirements. SET For high-grade material codes, the PLC uses the acquired current material code M. ACT Make a judgment;

[0027] when:

[0028] M ACT =M SET The PLC determines that the current production is of a high-grade steel.

[0029] M ACT ≠M SET The PLC determines that the current production is for other grades of steel.

[0030] M ACT <1 or M ACT >M UL The PLC alarm exceeded the limit;

[0031] in,

[0032] M ACT ----Current steel coil material code, positive integer;

[0033] M SET ----Second-level setting material code, positive integer;

[0034] M UL ----Material code upper limit, positive integer.

[0035] Preferably, in S3, the rolling pass is automatically determined by the PLC system as follows:

[0036] The settings are configured as the last and previous rolling passes. When the current rolling pass reaches the set pass, the PLC makes a judgment.

[0037] when:

[0038] P ACT =P MAX -1, the PLC issues a judgment instruction and sends a pulse signal;

[0039] P ACT =P MAX The PLC issues a judgment instruction and sends a pulse signal;

[0040] P ACT <P MAX -1, the PLC does not make a judgment;

[0041] in,

[0042] P ACT ----Current rolling pass, a positive integer;

[0043] PMAX ----The current maximum number of passes in steel coil rolling.

[0044] Preferably, the method for setting the gain coefficient in S4 is as follows:

[0045] S41. Based on the tension deviation scanned by the PLC, i.e., the inlet tension feedback – tension setting, different deviation gain values ​​are determined for each change in absolute value, i.e.:

[0046] S411, when M ACT =M SET And P ACT =P MAX -1 o'clock:

[0047] Set tension deviation range 0≤T DIF When T1 ≤ T1, G1 = B 10 At this point, the roll gap is adjusted steadily based on the tension deviation;

[0048] Set the tension deviation range T1≤T DIF When T2 ≤ T2, G1 = K 11 ·T DIF +B 11 At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation;

[0049] Set the tension deviation range T2≤T DIF When T3 ≤ T3, G1 = B 12 At this point, the roll gap is adjusted steadily based on the tension deviation;

[0050] Set the tension deviation range T3≤T DIF When T ≤ T4, G1 = K 12 ·T DIF +B 13 At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation;

[0051] Set tension deviation range T4 <T DIF When G1 = 0, this is the dead zone for adjustment;

[0052] S412, when M ACT =M SET And P ACT =P MAX hour:

[0053] Set tension deviation range 0≤T DIF When T1 ≤ T1, G2 = B 20 At this point, the roll gap is adjusted steadily based on the tension deviation;

[0054] Set the tension deviation range T1≤T DIF When T2 ≤ T2, G2 = K 21 ·T DIF+B 21 At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation;

[0055] Set the tension deviation range T2≤T DIF When T3 ≤ T3, G2 = B 22 At this point, the roll gap is adjusted steadily based on the tension deviation;

[0056] Set the tension deviation range T3≤T DIF When T ≤ T4, G2 = K 22 ·T DIF +B 23 At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation;

[0057] Set tension deviation range T4 <T DIF When G2 = 0, this is the dead zone for adjustment;

[0058] in,

[0059] T DIF ----Tension deviation;

[0060] T1, T2, T3, T4 ---- Tension deviation range values;

[0061] G1, G2----Last pass deviation gain values;

[0062] K 11 K 12 B 10 B 11 B 12 B 13 K 21 K 22 B 20 B 21 B 22 B 23 ----Fitting constants;

[0063] S42. Based on the gain coefficient variation optimized by material code and pass number changes, the formula for calculating the tension regulating roll gap can be evolved into:

[0064] ΔS=-C' GATRP ×G×(T RENT -T FBENT )

[0065] -∫g GATR ×C' GATRI ×G×(T RENT -T FBENT )dt

[0066] in,

[0067] ΔS----Tension adjustment roller gap component;

[0068] T RENT ----Tension setting at the mill inlet;

[0069] T FBENT ----Tension feedback at the mill inlet;

[0070] C' GATRP ----Roll gap ATR proportional gain;

[0071] C' GATRI ----Integral gain of ATR at the roll gap;

[0072] g GATR ----Integral time constant, fixed period;

[0073] G----Tension deviation gain, which varies with steel grade and pass / fail.

[0074] Preferably, the method for eliminating abnormal interference factors in S5 is as follows:

[0075] S51. Elimination of factors causing abnormal tension deviation due to belt breakage:

[0076] When the tension deviation at the mill inlet or outlet is greater than the breakage tension setting, it is judged as a breakage of the strip in the mill.

[0077] According to the PLC's scanning cycle, a set number of tension feedback values ​​are read. If the difference between the value and the set tension value is greater than the pre-judged set value and exceeds the set delay, a belt breakage warning is issued, and the output of the tension deviation gain control is cut off.

[0078] S52. Troubleshooting tension gauge malfunctions:

[0079] When the tension gauge hardware alarms, the tension feedback value cannot be output, and the deviation from the tension set value will reach the adjustment dead zone set value. The tension deviation gain output is 0. At this time, the calculated feedback tension is introduced to continue adjustment.

[0080] Feedback tension calculation formula:

[0081]

[0082]

[0083] in,

[0084] F CAL ----Calculate tension;

[0085] T CAL ----Calculate the tension torque;

[0086] D----Mandrel diameter;

[0087] G----Gear reduction ratio;

[0088] g----constant;

[0089] I FB ----Current feedback;

[0090] I LOSS ----Mechanical loss current;

[0091] I FORCE Forced current;

[0092] V FB ----Motor speed feedback;

[0093] I RATED ----Motor rated current;

[0094] P RATED ----Motor rated power;

[0095] When the PLC detects an alarm signal from the tension meter hardware or communication, it immediately cuts off the feedback value measured by the tension meter, starts calculating the feedback tension, and continues to adjust according to the tension deviation to meet the needs of thickness control.

[0096] Compared with the prior art, the beneficial effects of the present invention are:

[0097] This invention provides an optimized method for controlling the mixed thickness of cold-rolled high-grade silicon steel. Compared to traditional control and adjustment methods, this method can identify high-grade steel and the last rolling pass and adjust different parameters accordingly. Using this invention, the abnormal thickness fluctuations caused by changes in roll gap due to tension or other factors during the rolling of high-grade steel and the last pass can be largely resolved, reducing quality defects, increasing yield, reducing downtime quality losses caused by tension gauge hardware failures, reducing downtime, and improving the technical level of enterprises. Attached Figure Description

[0098] Figure 1 This is a schematic diagram illustrating the principle of an optimization method for controlling the mixed thickness in cold-rolled high-grade silicon steel according to the present invention.

[0099] Figure 2 This is a graph showing the G1 gain coefficient of the present invention;

[0100] Figure 3 This is a graph showing the G2 gain coefficient of the present invention;

[0101] Figure 4 This is a simulated trend data graph of the roll gap adjustment amount according to the present invention. Detailed Implementation

[0102] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0103] To resolve the existing issues, please refer to Figure 1 This embodiment provides the following technical solution:

[0104] An optimization method for controlling the mixed thickness in cold-rolled high-grade silicon steel rolling includes the following steps:

[0105] Step 1: The effect of tension adjustment roller gap on mixing thickness control;

[0106] Step 2: Automatically determine the steel type and material using the PLC system;

[0107] Step 3: The rolling pass is automatically determined by the PLC system;

[0108] Step 4: Set the gain coefficient;

[0109] Step 5: Eliminate abnormal interference factors.

[0110] The tension adjustment roller gap in step one affects the control of the mixing thickness, including the following steps:

[0111] Step 1: When the rolling passes and speed meet the set requirements, the mixed thickness control function is activated. The tension on the mill inlet side is controlled by the roll gap. The tension is adjusted using the inlet side tension signal and the PI controller of the roll gap position to ensure stable rolling tension and eliminate thickness deviation.

[0112] Step 2: Formula for calculating the tension adjustment roller gap:

[0113] ΔS=-C GATRP ×(T RENT -T FBENT )-∫g GATR ×C GATRI ×(T RENT -T FBENT )dt

[0114] in,

[0115] ΔS----Tension regulating roller gap component

[0116] T RENT ----Tension setting at the mill inlet

[0117] T FBENT ----Tension feedback at the mill inlet

[0118] C GATRP ----Roll gap ATR proportional gain

[0119] C GATRI ----Integral gain of roll gap ATR

[0120] g GATR ----Integral time constant, fixed period

[0121] According to the calculation formula, the difference between the inlet tension setting and the feedback is used to obtain the roll gap adjustment amount through proportional-integral regulation, which ultimately affects the adjustment of the mill roll gap. When rolling to the last pass, the strip thickness decreases, making tension control difficult. Occasional changes in tension deviation will increase the roll gap adjustment amount, leading to abnormal thickness changes. Therefore, tension adjustment of the roll gap is an important component of thickness control in the last pass. For different steel grades and different passes, in addition to reducing the influence of the tension setting issued by the secondary control unit and the tension deviation calculated from the actual tension detected by the tension gauge, the weight of the tension deviation in the proportional and integral regulator can be automatically adjusted to match the tension roll gap adjustment during the rolling of high-grade steel grades and passes, thereby eliminating abnormal thickness deviations that occur during the rolling process.

[0122] Step two, which involves automatically determining the steel type and material using a PLC system, includes the following steps:

[0123] The first and second level systems assign a material code to the steel grade being rolled. Before the current steel grade is rolled, the material code is sent to the first level PLC via electronic message along with other steel grade information. The PLC system collects the material code of the steel grade being rolled in real time and makes a judgment.

[0124] Step 2: Assume 1 ≤ M SET ≤M UL Determine a specific M position according to process requirements. SET For high-grade material codes, the PLC uses the acquired current material code M. ACT Make a judgment.

[0125] when:

[0126] M ACT =M SET The PLC determined that the current production is for high-grade steel.

[0127] M ACT ≠M SET If the PLC makes a decision, it will determine that the current production is for other grades of steel.

[0128] M ACT <1 or M ACT >M UL PLC alarm exceeds limit

[0129] in,

[0130] M ACT ----Current steel coil material code, positive integer

[0131] M SET ----Second-level setting material code, positive integer

[0132] M UL ----Material code upper limit, positive integer

[0133] Step three involves the PLC system automatically determining the rolling pass number as follows:

[0134] When the raw material thickness deviation is normal, the stable rolling of the last two passes has a greater impact on the thickness accuracy of the finished coil. Therefore, the adjustment passes are set as the last pass and the previous pass. When the current rolling pass reaches the set pass, the PLC makes a judgment.

[0135] when:

[0136] P ACT =P MAX -1, the PLC issues a judgment instruction and sends a pulse signal.

[0137] P ACT =P MAX The PLC issues a judgment instruction and sends a pulse signal.

[0138] P ACT <P MAX -1, the PLC does not make a judgment.

[0139] in,

[0140] P ACT ----Current rolling pass, positive integer

[0141] P MAX ----Current maximum number of passes in steel coil rolling

[0142] Please see Figures 1-4 Step four, setting the gain coefficient, includes the following steps:

[0143] Step 1: Since both the proportional and integral adjustment of the tension adjustment roll gap component ΔS are related to the tension deviation, and the gain coefficient of the tension deviation can be determined based on the actual rolling conditions, a change in the tension deviation gain can be introduced during the last two passes of rolling high-grade silicon steel. Different deviation gain values ​​can be determined based on the absolute value change of the tension deviation scanned by the PLC (i.e., the inlet tension feedback – tension setting), i.e.:

[0144] 1. When M ACT =M SET And P ACT =P MAX-1 o'clock

[0145] Set tension deviation range 0≤T DIF When T1 ≤ T1, G1 = B 10 At this point, the roll gap is adjusted steadily based on the tension deviation;

[0146] Set the tension deviation range T1≤T DIF When T2 ≤ T2, G1 = K 11 ·T DIF +B 11 At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation;

[0147] Set the tension deviation range T2≤T DIF When T3 ≤ T3, G1 = B 12 At this point, the roll gap is adjusted steadily based on the tension deviation;

[0148] Set the tension deviation range T3≤T DIF When T ≤ T4, G1 = K 12 ·T DIF +B 13 At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation;

[0149] Set tension deviation range T4 <T DIF When G1 = 0, this is the dead zone for adjustment;

[0150] II. When M ACT =M SET And P ACT =P MAX hour

[0151] Set tension deviation range 0≤T DIF When T1 ≤ T1, G2 = B 20 At this point, the roll gap is adjusted steadily based on the tension deviation;

[0152] Set the tension deviation range T1≤T DIF When T2 ≤ T2, G2 = K 21 ·T DIF +B 21 At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation;

[0153] Set the tension deviation range T2≤T DIF When T3 ≤ T3, G2 = B 22 At this point, the roll gap is adjusted steadily based on the tension deviation;

[0154] Set the tension deviation range T3≤T DIF When T ≤ T4, G2 = K 22 ·T DIF +B 23At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation;

[0155] Set tension deviation range T4 <T DIF When G2 = 0, this is the dead zone for adjustment;

[0156] in,

[0157] T DIF ----Tension Deviation

[0158] T1, T2, T3, T4 ---- Tension deviation range values

[0159] G1, G2 ---- Last pass deviation gain values

[0160] K 11 K 12 B 10 B 11 B 12 B 13 K 21 K 22 B 20 B 21 B 22 B 23 ----Fitting constants

[0161] The second step involves optimizing the gain coefficient based on material codes and pass variations. The formula for calculating the tension-adjusting roll gap can then be derived as follows:

[0162] ΔS=-C' GATRP ×G×(T RENT -T FBENT )

[0163] -∫g GATR ×C' GATRI ×G×(T RENT -T FBENT )dt

[0164] in,

[0165] ΔS----Tension regulating roller gap component

[0166] T RENT ----Tension setting at the mill inlet

[0167] T FBENT ----Tension feedback at the mill inlet

[0168] C' GATRP ----Roll gap ATR proportional gain

[0169] C' GATRI ----Integral gain of roll gap ATR

[0170] g GATR ----Integral time constant, fixed period

[0171] G----Tension deviation gain, varying with steel grade and pass / flight number

[0172] Specific methods:

[0173] I. Setting up the function generator:

[0174] (1) Configure the G1 gain function generator:

[0175]

[0176] (2) Configure the G2 gain function generator:

[0177]

[0178] Setting conditions procedure:

[0179] (1) Write a PLC control program to determine whether the mixed AGC function is engaged and whether the tension adjustment roller gap condition is met, and output a constant "1" judgment signal C1.

[0180] (2) Write a PLC control program to identify the material code. When the material code issued by the secondary level meets the high grade setting code, output a constant "1" identification signal C2.

[0181] (3) Write a PLC control program to determine the rolling pass. When the current rolling pass reaches the second to last, output a constant "1" judgment signal C3; when the current rolling pass reaches the last, output a constant "1" judgment signal C4.

[0182] (4) Write a PLC control program to determine the actual tension value of the previous and next scanning cycles. When the deviation between the actual tension and the set tension is greater than the set threshold and exceeds the set delay, output a constant "1" judgment signal C5.

[0183] (5) Write a PLC control program to determine whether the tension gauge hardware is normal and output a constant "1" judgment signal C6 when a fault is detected.

[0184] III. Setting the execution procedure:

[0185] (1) Write a PLC program and set that when condition C1 is “1”, condition C2 is “1”, condition C3 is “1”, condition is “1”, and condition C6 is “0”, the gain coefficient G1 is introduced in the calculation of formula (2) to calculate the adjustment amount ΔS of the tension adjustment roll gap under the current high grade steel, current pass, and current gain.

[0186] (2) Write a PLC program and set the condition C1 to "1", condition C2 to "1", condition C4 to "1", condition C6 to "0", and input the gain coefficient G2 in the formula (2) calculation to calculate the adjustment amount ΔS' of the tension adjustment roll gap under the current high grade steel, current pass, and current gain.

[0187] (3) Write a PLC program to set the input of gain coefficients G1 and G2 to be cut off when C5 condition is “1”, and ΔS stops adjusting the roll gap due to belt breakage and machine stop.

[0188] (4) Write a PLC program to cut off the actual tension input detected by the original tension gauge when the C6 condition is “1”, replace it with the calculated tension input in formula (3), calculate the tension deviation, and output the gain according to the gain coefficient function generator to continue to adjust the roll gap.

[0189] IV. Simulated execution results:

[0190] (1) G1 gain coefficient as follows Figure 2

[0191] (2) G2 gain coefficient as follows Figure 3

[0192] (3) Simulated trend data of roll gap adjustment, such as Figure 4

[0193] Step five, eliminating abnormal interference factors, includes the following steps:

[0194] The first step is that under actual production conditions, there may be a variety of other factors that cause abnormal changes in tension deviation. Adjusting the roll gap for such changes can cause sudden changes in the thickness of the strip at the mill exit. Therefore, it is necessary to consider the tension deviation changes caused by these factors to reduce system misjudgments.

[0195] Step 2: Eliminating factors causing abnormal tension deviation due to belt breakage:

[0196] When the tension deviation at the mill inlet or outlet exceeds the set strip breakage tension (which can be set according to the mill speed range), it is judged as strip breakage. Before and during strip breakage, the strip tension is in a highly unstable state. If roll gap adjustments are made based on the tension deviation at this time, it will inevitably exacerbate the abnormal changes in tension and thickness. Therefore, strip breakage prediction is necessary to eliminate interference from strip breakage.

[0197] According to the PLC's scanning cycle, a set number of tension feedback values ​​are read. If the difference between the value and the set tension value is greater than the pre-judged set value and exceeds the set delay, a belt breakage warning is issued, and the output of the tension deviation gain control is cut off.

[0198] Step 3: Troubleshooting tension meter malfunctions:

[0199] When the tension gauge hardware alarms, the tension feedback value cannot be output, and the deviation from the tension set value will reach the adjustment dead zone set value. The tension deviation gain output is 0. At this time, the calculated feedback tension can be introduced to continue the adjustment, complete the current steel coil rolling, and improve the yield.

[0200] Feedback tension calculation formula:

[0201]

[0202]

[0203] in,

[0204] F CAL ----Calculate tension

[0205] T CAL ----Calculate tension torque

[0206] D----Mandrel diameter

[0207] G----Gear reduction ratio

[0208] g----constant

[0209] I FB ----Current Feedback

[0210] I LOSS ----Mechanical loss current

[0211] I FORCE Forced current

[0212] V FB ----Motor speed feedback

[0213] I RATED ----Motor rated current

[0214] P RATED ----Motor rated power

[0215] When the PLC detects an alarm signal from the tension meter hardware or communication, it immediately cuts off the feedback value measured by the tension meter, starts calculating the feedback tension, and continues to adjust according to the tension deviation to meet the needs of thickness control.

[0216] In summary, the optimized method for controlling the mixed thickness of cold-rolled high-grade silicon steel, as proposed in this invention, compared to traditional control and adjustment methods, utilizes a PLC system to identify high-grade steel grades and the final rolling pass, and matches different parameters for adjustment. Using this invention, the problem of abnormal thickness fluctuations caused by changes in roll gap due to tension or other factors during the rolling of high-grade steel grades and the final pass can be solved, reducing quality defects, increasing yield, shortening downtime caused by tension gauge hardware failures, and improving the enterprise's technical level.

[0217] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0218] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An optimization method for controlling the mixed thickness in cold-rolled high-grade silicon steel, characterized in that: Includes the following steps: S1. Tension adjustment roller gap affects the control of mixing thickness; S2. The steel type and material are automatically determined by the PLC system; S3. The rolling pass is automatically determined by the PLC system; S4. Set the gain coefficient; S5. Eliminate abnormal interference factors; The influence of tension adjustment roller gap on mixing thickness control in S1 includes the following steps: S11. When the rolling pass and speed reach the set requirements, the mixed thickness control function is activated. The tension on the mill inlet side is controlled by the roll gap and adjusted using the inlet side tension signal and the PI controller of the roll gap position. S12, Formula for calculating tension adjusting roller gap: in, ----Tension Adjustment Roller Gap Component ----Tension setting at the mill inlet ----Tension feedback at the mill inlet ----Roll gap ATR proportional gain ----Integral gain of roll gap ATR ----Integral time constant, fixed period According to the calculation formula, the difference between the inlet tension setting and the feedback is used to obtain the adjustment amount of the roll gap through proportional-integral adjustment, which ultimately affects the adjustment of the mill roll gap. The automatic determination of steel grade and material by the PLC system in S2 includes the following steps: S21. The secondary system assigns a material code to the rolled steel grade. Before the current steel grade is rolled, the material code is sent to the primary PLC along with other steel grade information via electronic message. The PLC system collects the material code of the rolled steel grade in real time and makes a judgment. S22, Let Determine one of them according to the process requirements. For high-grade material codes, the PLC uses the currently acquired material code. Make a judgment; when: The PLC determines that the current production is of a high-grade steel. The PLC determines that the current production is for other grades of steel. or The PLC alarm exceeded the limit; in, ----Current steel coil material code, positive integer; ----Second-level setting material code, positive integer; ----Material code upper limit, positive integer; In S3, the rolling pass is automatically determined by the PLC system as follows: The settings are configured as the last and previous rolling passes. When the current rolling pass reaches the set pass, the PLC makes a judgment. when: The PLC issues a judgment instruction and sends a pulse signal; The PLC issues a judgment instruction and sends a pulse signal; The PLC does not make any judgments; in, ----Current rolling pass, a positive integer; ----Current maximum number of passes in steel coil rolling; The method for setting the gain coefficient in S4 is as follows: S41. Based on the tension deviation scanned by the PLC, i.e., the inlet tension feedback – tension setting, different deviation gain values ​​are determined for each change in absolute value, i.e.: S411, when and hour: Set tension deviation range hour, At this point, the roll gap is adjusted steadily based on the tension deviation; Set tension deviation range hour, At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation; Set tension deviation range hour, At this point, the roll gap is adjusted steadily based on the tension deviation; Set tension deviation range hour, At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation; Set tension deviation range hour, This is the adjustment dead zone; S412, when and hour: Set tension deviation range hour, At this point, the roll gap is adjusted steadily based on the tension deviation; Set tension deviation range hour, At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation; Set tension deviation range hour, At this point, the roll gap is adjusted steadily based on the tension deviation; Set tension deviation range hour, At this time, the roll gap is linearly and dynamically adjusted according to the tension deviation; Set tension deviation range hour, This is the adjustment dead zone; in, ----Tension deviation; , , , ----Tension deviation range; ----Previous pass tension deviation gain value; ----Last pass tension deviation gain value; , , , , , , , , , , , ----Fitting constants; S42. Based on the gain coefficient variation optimized by material code and pass number changes, the formula for calculating the tension regulating roll gap can be evolved into: in, ----Tension adjustment roller gap component; ----Tension setting at the mill inlet; ----Tension feedback at the mill inlet; ----Roll gap ATR proportional gain; ----Integral gain of ATR at the roll gap; ----Integral time constant, fixed period; ----Tension deviation gain varies with steel grade and pass / flight number; The method for eliminating abnormal interference factors in S5 is as follows: Elimination of factors causing abnormal tension deviation due to belt breakage: When the tension deviation at the mill inlet or outlet is greater than the breakage tension setting, it is judged as a breakage of the strip in the mill. Based on the PLC's scanning cycle, a set number of tension feedback values ​​are read. If the difference between the value and the set tension value is greater than the pre-judgment set value and exceeds the set delay, a belt breakage warning is issued, and the output of the tension deviation gain control is cut off.

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