阅读说明：本技术 自适应的单机架轧机前馈厚度控制方法 (Self-adaptive single-stand rolling mill feedforward thickness control method ) 是由 王志军 吴有生 陈跃华 于 2019-10-16 设计创作，主要内容包括：本发明提供了一种自适应的单机架轧机前馈厚度控制方法,包括以下步骤：获取带钢进入入口测厚仪时的厚度H<Sub>c</Sub>,计算辊缝调节量△S；压下控制系统根据计算的辊缝调节量实施辊缝调节；获取带钢经过出口测厚仪时的厚度h<Sub>c</Sub>,根据带钢经过出口测厚仪时的厚度h<Sub>c</Sub>计算修正系数K<Sub>Q</Sub>；循环执行上述步骤,始终利用上一次计算的修正系数K<Sub>Q</Sub>来计算辊缝调节量△S。本发明通过前馈极大消除了入口原料对成品厚度偏差的影响,保证了带钢产品质量；通过根据带钢经过出口测厚仪时的厚度计算修正系数对辊缝调节量进行计算,自适应地对辊缝进行调节,保证了带钢到达目标厚度,降低了对塑性系数高精度的依赖性；通过合理的延时,保证压下控制系统施加辊缝到预期的带钢位置。(The invention provides a self-adaptive single-stand rolling mill feedforward thickness control method, which comprises the following steps of: obtaining thickness H of strip steel when entering an inlet thickness gauge c Calculating the roll gap adjustment quantity delta S; the pressing control system carries out roll gap adjustment according to the calculated roll gap adjustment quantity; obtaining the thickness h of the strip steel when the strip steel passes through the outlet thickness gauge c According to the thickness h of the strip steel passing through the outlet thickness gauge c Calculating a correction factor K Q (ii) a The steps are executed circularly, and the correction coefficient K calculated last time is always utilized Q The roll gap adjustment quantity deltaS is calculated. The invention greatly eliminates the influence of the inlet raw materials on the thickness deviation of the finished product through feedforward, and ensures the quality of the strip steel product; the roll seam regulating quantity is calculated by calculating the correction coefficient according to the thickness of the strip steel passing through the outlet thickness gauge, the roll seam is regulated in a self-adaptive manner, the thickness of the strip steel reaching a target is ensured, and the high-precision dependence on the plastic coefficient is reduced; and the roll gap applied by the pressing control system to the expected strip steel position is ensured through reasonable time delay.)

1. A self-adaptive single-stand rolling mill feedforward thickness control method is characterized by comprising the following steps:

s1: obtaining thickness H of strip steel when entering an inlet thickness gauge_cAnd calculating the roll gap adjustment quantity delta S in the following way:

△S＝(H_r－H_c)*K_Q*Q/C_p

in the formula: delta S is the roll gap adjustment quantity; h_rSet the thickness of the incoming material, H_cFor strip steel entering inlet thickness gaugeThickness; k_QThe correction coefficient is the strip steel plasticity coefficient, and the initial value of the correction coefficient in each speed section is 1; q is the strip steel plasticity coefficient; c_pIs the stiffness coefficient of the rolling mill;

s2: the pressing control system carries out roll gap adjustment according to the calculated roll gap adjustment quantity;

s3: obtaining the thickness h of the strip steel when the strip steel passes through the outlet thickness gauge_cAccording to the thickness h of the strip steel passing through the outlet thickness gauge_cCalculating a correction factor K_Q；

The above steps S1-S3 are executed in a loop, and the correction coefficient K calculated last time is always used_QThe roll gap adjustment quantity deltaS is calculated.

2. The adaptive single stand mill feed forward thickness control method of claim 1, wherein: obtaining the thickness H of the strip steel when the strip steel enters the inlet thickness gauge_cCalculating the adjustment quantity Delta S of the roll gap, and obtaining the thickness h of the strip steel when the strip steel passes through an outlet thickness gauge_cAiming at the strip steel with the same point or the same section of micro-section strip steel.

3. The adaptive single stand mill feed forward thickness control method of claim 2, wherein: if the micro-segment strip steel is the micro-segment strip steel, the average thickness value of each position of the micro-segment strip steel in the length when the micro-segment strip steel passes through the inlet thickness gauge is obtained in step S1, roll gap adjustment is carried out on the center point of the micro-segment strip steel in step S2, and the average thickness value of each position of the micro-segment strip steel in the length when the micro-segment strip steel passes through the outlet thickness gauge is obtained in step S3.

4. The adaptive single stand mill feed forward thickness control method of claim 2, wherein: if the micro-section strip steel is used, the inlet length of the micro-section strip steel is equal to the distance which is sampled and passed by N times of inlet thickness and is smaller than 1/3 of the distance between the inlet thickness gauge and the roll gap.

5. A feed-forward thickness control method for an adaptive single stand rolling mill as set forth in claim 1, wherein said step S2 specifically comprises:

s201: acquiring the speed in real time, acquiring the real-time position of the central point of the strip steel according to the sampling period integral, and predicting the remaining time about to reach the roll gap;

s202: obtaining a nonlinear relation between rolling force and reduction speed of the rolling mill through a pressing test, and predicting response time required by roll gap change under the current rolling force in advance;

s303: and (4) taking the difference delta t between the residual time of the step (S201) and the response time of the step (S202) as delay time, and pressing down the control system to adjust the roll gap after the delay delta t.

6. The feed-forward thickness control method for an adaptive single stand rolling mill according to claim 1, wherein in step S3, the correction coefficient K is set_QThe calculation method of (2) is as follows:

K_Q ^new＝β*(h_c/h_r)+(1－β)K_Q ^old

in the formula: k_Q ^newIs a new correction factor; k_Q ^oldThe correction coefficient used under the last same-speed platform; h is_rFor a set target, hc is the thickness of the strip steel when passing through an outlet thickness gauge; beta is a smoothing coefficient.

7. The adaptive single stand mill feed forward thickness control method of claim 6, wherein: the value range of beta is 0.01-0.1.

Technical Field

The invention relates to the technical field of steel rolling control, in particular to a self-adaptive single-stand rolling mill feedforward thickness control method.

Background

The thickness is one of the most main dimension and quality indexes of the plate and the strip, and the instrument arrangement of the single-stand rolling mill comprises an inlet thickness gauge, an outlet thickness gauge, an inlet speed measuring device, an outlet speed measuring device and the like; the Control mode mainly comprises the modes of Automatic thickness Control (Automatic Gauge Control) such as feedforward Control, second flow Control, monitoring Control and the like. The feed-forward AGC measures the inlet thickness before strip steel reaches a roll gap, then estimates a possible thickness error of a rolled strip in advance, calculates the roll gap adjustment amount required for eliminating the thickness error and applies the roll gap adjustment amount to a hydraulic pressure reduction control system. Therefore, the thickness deviation of the finished product strip steel caused by the thickness fluctuation of the strip steel inlet can be reduced, and the precision of the whole thickness control is improved. The calculation formula is as follows:

△S＝－△H*Q/C_p

in the formula: delta S is the roll gap adjustment quantity; delta H is the incoming material thickness error; q is the strip steel plasticity coefficient; c_pIs the rigidity coefficient of the rolling mill.

However, the feedforward AGC has an inherent disadvantage that the control effect cannot be known, and the control effect depends on the calculation accuracy of the strip plasticity coefficient. The patent of publication No. CN102029292A improves the accuracy of feed-forward thickness control by adding a mechanical property detector at the entrance of the rolling mill, which undoubtedly increases the production complexity and increases the unit investment cost.

Disclosure of Invention

The invention aims to provide a self-adaptive single-stand rolling mill feedforward thickness control method, and aims to solve the problem that the control effect of the existing feedforward AGC (automatic gain control) cannot be known and depends on the calculation precision of the strip steel plasticity coefficient.

The invention is realized by the following steps:

the invention provides a self-adaptive single-stand rolling mill feedforward thickness control method, which comprises the following steps:

s1: obtaining thickness H of strip steel when entering an inlet thickness gauge_cAnd calculating the roll gap adjustment quantity delta S in the following way:

△S＝(H_r－H_c)*K_Q*Q/C_p

in the formula: delta S is the roll gap adjustment quantity; h_rSet the thickness of the incoming material, H_cThe thickness of the strip steel when entering an inlet thickness gauge；K_QThe correction coefficient is the strip steel plasticity coefficient, and the initial value of the correction coefficient in each speed section is 1; q is the strip steel plasticity coefficient; c_pIs the stiffness coefficient of the rolling mill;

s2: the pressing control system carries out roll gap adjustment according to the calculated roll gap adjustment quantity;

s3: obtaining the thickness h of the strip steel when the strip steel passes through the outlet thickness gauge_cAccording to the thickness h of the strip steel passing through the outlet thickness gauge_cCalculating a correction factor K_Q；

The above steps S1-S3 are executed in a loop, and the correction coefficient K calculated last time is always used_QThe roll gap adjustment quantity deltaS is calculated.

Further, the thickness H of the strip steel when entering the inlet thickness gauge is obtained_cCalculating the adjustment quantity Delta S of the roll gap, and obtaining the thickness h of the strip steel when the strip steel passes through an outlet thickness gauge_cAiming at the strip steel with the same point or the same section of micro-section strip steel.

Further, if the micro-segment strip steel is targeted, the average thickness value of the micro-segment strip steel at each position of the length of the micro-segment strip steel passing through the inlet thickness gauge is obtained in step S1, roll gap adjustment is performed on the center point of the micro-segment strip steel in step S2, and the average thickness value of the micro-segment strip steel at each position of the length of the micro-segment strip steel passing through the outlet thickness gauge is obtained in step S3.

Further, if the micro-segment strip steel is aimed at, the inlet length of the micro-segment strip steel is the distance which is sampled and passed by N times of inlet thickness and is smaller than 1/3 of the distance between the inlet thickness gauge and the roll gap.

Further, the step S2 specifically includes:

s201: acquiring the speed in real time, acquiring the real-time position of the central point of the strip steel according to the sampling period integral, and predicting the remaining time about to reach the roll gap;

s202: obtaining a nonlinear relation between rolling force and reduction speed of the rolling mill through a pressing test, and predicting response time required by roll gap change under the current rolling force in advance;

s303: and (4) taking the difference delta t between the residual time of the step (S201) and the response time of the step (S202) as delay time, and pressing down the control system to adjust the roll gap after the delay delta t.

Further, in step S3, the coefficient K is corrected_QThe calculation method of (2) is as follows:

K_Q ^new＝β*(h_c/h_r)+(1－β)K_Q ^old

in the formula: k_Q ^newIs a new correction factor; k_Q ^oldThe correction coefficient used under the last same-speed platform; h is_rFor a set target, hc is the thickness of the strip steel when passing through an outlet thickness gauge; beta is a smoothing coefficient.

Further, the value range of beta is 0.01-0.1.

Compared with the prior art, the invention has the following beneficial effects:

the self-adaptive single-stand rolling mill feed-forward thickness control method provided by the invention greatly eliminates the influence of inlet raw materials on the thickness deviation of finished products through feed-forward, and ensures the quality of strip steel products; the roll seam regulating quantity is calculated by calculating the correction coefficient according to the thickness of the strip steel passing through the outlet thickness gauge, the roll seam is regulated in a self-adaptive manner, the thickness of the strip steel reaching a target is ensured, and the high-precision dependence on the plastic coefficient is reduced; and the roll gap applied by the pressing control system to the expected strip steel position is ensured through reasonable time delay.

Drawings

FIG. 1 is a schematic view of main equipment and a detector of a single stand rolling mill according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a certain tiny section of strip steel before and after entering a roller according to an embodiment of the present invention;

FIG. 3 is a flowchart of a method for controlling feed-forward thickness of a self-adaptive single stand rolling mill according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

As shown in figure 1, the main equipment and the detecting instrument of the single-stand rolling mill comprise uncoiling and coiling equipment 1, a steering roll 2, a speed measuring device 3, a thickness gauge 4, a roller 5 and a pressing control system 6. The strip steel is uncoiled from one side uncoiling and coiling equipment, enters between an upper roller and a lower roller through a steering roller, passes through an inlet speed measuring device and an inlet thickness gauge, is pressed down by a control system to control the roller gap, then reaches an outlet thickness gauge and an outlet speed measuring device, passes through the steering roller, and then reaches the other side uncoiling and coiling equipment to be coiled. And performing a plurality of passes in a reciprocating manner to press the strip steel to the target thickness.

As shown in FIG. 2, the ends of a strip of a certain micro-segment are respectively represented by H, C, T, which has not entered the roll gap at time t1, is rolling at time t2, and is in a rolling finish state at time t 3.

As shown in fig. 3, an embodiment of the present invention provides an adaptive feed-forward thickness control method for a single-stand rolling mill, including the following steps:

s1: obtaining thickness H of strip steel when entering an inlet thickness gauge_cAnd calculating the roll gap adjustment quantity delta S in the following way:

△S＝(H_r－H_c)*K_Q*Q/C_p

in the formula: delta S is the roll gap adjustment quantity; h_rSet the thickness of the incoming material, H_cThe thickness of the strip steel entering the inlet thickness gauge; k_QThe correction coefficient is the strip steel plasticity coefficient, and the initial value of the correction coefficient in each speed section is 1; q is the strip steel plasticity coefficient; c_pIs the stiffness coefficient of the rolling mill;

wherein H_rDerived from the set value, C_pQ is also derived from the set value for a pre-measured constant. Q is related to speed, and Q values of different speed sections are different for rolled pieces under a certain process. K_QIn relation to the speed, the initial value is 1 in each speed segment.

S2: and the pressing control system implements roll gap adjustment according to the calculated roll gap adjustment amount.

S3: obtaining strip steelThickness h when passing through outlet thickness gauge_cAccording to the thickness h of the strip steel passing through the outlet thickness gauge_cCalculating a correction factor K_Q。

The above steps S1-S3 are executed in a loop, and the correction coefficient K calculated last time is always used_QTo calculate the roll gap adjustment Δ S, i.e.: the last calculated correction coefficient K_QSubstituting the roll gap adjustment amount into a roll gap adjustment amount calculation formula to calculate the roll gap adjustment amount.

The self-adaptive single-stand rolling mill feed-forward thickness control method provided by the embodiment of the invention greatly eliminates the influence of inlet raw materials on the thickness deviation of a finished product through feed-forward, and ensures the quality of a strip steel product; the roll seam regulating quantity is calculated by calculating the correction coefficient according to the thickness of the strip steel passing through the outlet thickness gauge, the roll seam is regulated in a self-adaptive manner, the thickness of the strip steel reaching a target is ensured, and the high-precision dependence on the plastic coefficient is reduced.

In the above embodiment, the thickness H of the strip steel entering the inlet thickness gauge is obtained_cCalculating the adjustment quantity Delta S of the roll gap, and obtaining the thickness h of the strip steel when the strip steel passes through an outlet thickness gauge_cAiming at the strip steel with the same point or the same section of micro-section strip steel. If the micro-segment strip steel is the micro-segment strip steel, the average thickness value of the micro-segment strip steel at each position of the time length when the micro-segment strip steel passes through the inlet thickness gauge, namely H1 is obtained_cThe average thickness of the inlet of the micro-segment strip steel is adjusted according to the central point of the micro-segment strip steel in the step S2, and the average thickness of the micro-segment strip steel at each position of the length of the micro-segment strip steel passing through an outlet thickness gauge, namely h is obtained in the step S3_cThe average value of the thickness of the micro-section strip steel outlet is obtained. The inlet length of the micro-segment strip steel is the distance that N times of inlet thickness samples pass, for example, the sampling frequency is 4ms, the current inlet speed is 10m/s, N is 5, and the length is 4ms 10m/s 0.16 m. Meanwhile, the length of the inlet of the micro-section strip steel is less than 1/3 of the distance between the inlet thickness gauge and the roll gap.

Preferably, the step S2 specifically includes:

s201: acquiring the speed in real time, acquiring the real-time position of the central point of the strip steel according to the sampling period integral, and predicting the remaining time about to reach the roll gap;

s202: obtaining a nonlinear relation between rolling force and reduction speed of the rolling mill through a pressing test, and predicting response time required by roll gap change under the current rolling force in advance;

s303: and (4) taking the difference delta t between the residual time of the step (S201) and the response time of the step (S202) as delay time, and pressing down the control system to adjust the roll gap after the delay delta t.

The embodiment ensures that the roll gap applied by the pressing control system is in the expected position of the strip steel through reasonable time delay.

Preferably, in step S3, the correction coefficient K_QThe calculation method of (2) is as follows:

K_Q ^new＝β*(h_c/h_r)+(1－β)K_Q ^old

in the formula: k_Q ^newIs a new correction factor; k_Q ^oldThe correction coefficient used under the last same-speed platform; h is_rFor a set target, hc is the thickness of the strip steel when passing through an outlet thickness gauge; beta is a smoothing coefficient;

wherein h is_rThe beta value is from a set value, and the beta value ranges from 0 to 1, preferably from 0.01 to 0.1.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.