CN-122007172-A - Rolling mill rolling thickness compensation control method based on AGC hydraulic cylinder system

CN122007172ACN 122007172 ACN122007172 ACN 122007172ACN-122007172-A

Abstract

The invention belongs to the technical field of rolling thickness compensation of rolling mills, and particularly discloses a rolling thickness compensation control method of a rolling mill based on an AGC hydraulic cylinder system, which is characterized in that continuous steel plates are cut into independent microelements with time sequence marks, the residual travel of each microelement spacing roll gap is accurately calculated through real-time speed integration, when the rolling speed is changed severely, the actual moment of each microelement reaching the roll gap can be accurately mapped, the triggering time of a compensation instruction is ensured to be accurately synchronous with the spatial position of the microelement, meanwhile, after the steel plate infinitesimal to be compensated is identified, the rolling force variation response of the rolled finished leading infinitesimal is utilized to predict that the rolling force mutation is caused after the current infinitesimal to be compensated enters the roll gap, and the roll gap compensation is triggered only when the rolling force mutation is predicted to be caused, so that the online verification of the thickness deviation disturbance effectiveness is realized, and the redundant adjustment and the extra system disturbance caused by blind compensation can be avoided to the greatest extent.

Inventors

ZHU XIAOHU
QIAN YONGFA
MA YANAN
ZHAO LING

Assignees

江苏科茂新材料科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. The rolling thickness compensation control method of the rolling mill based on the AGC hydraulic cylinder system is characterized by comprising the following steps: Measuring the thickness and the running speed of a steel plate at an inlet of a rolling mill in real time, marking each thickness measuring point as a steel plate infinitesimal with a time sequence number, and tracking the residual travel of a roll gap at each infinitesimal distance; the infinitesimal with the thickness measurement exceeding the allowable range is recorded as infinitesimal to be compensated, the thickness deviation amount is recorded, and the number, the deviation amount and the residual travel of the infinitesimal to be compensated are stored in a list to be compensated; judging whether the compensation necessity exists for each element to be compensated according to the rolling force response of the leading element before entering the roll gap, and if not, removing the element from the list to be compensated; sequentially processing each element to be compensated from the list to be compensated according to the residual travel from small to large, and determining compensation triggering time according to the residual travel and response delay time of the hydraulic system; When compensation is triggered, a roll gap position adjustment quantity is generated according to the thickness deviation quantity of the micro elements to be compensated and is overlapped to a roll gap set value, a hydraulic cylinder is controlled by a hydraulic servo valve to execute compensation in each control period, and when the compensation trigger time of a plurality of micro elements to be compensated is close, space-time cooperative processing of multi-micro element continuous compensation is performed.
2. The rolling thickness compensation control method of the rolling mill based on the AGC hydraulic cylinder system of claim 1, wherein the real-time measuring of the thickness of the steel plate at the inlet of the rolling mill and the running speed are as follows: The thickness measurement value of the steel plate along the length direction is obtained in real time from a thickness gauge arranged on the inlet side of the rolling mill, and meanwhile, the running speed of the steel plate is obtained in real time from a coder on the transmission side of the rolling mill.
3. The method for controlling rolling thickness compensation of a rolling mill based on an AGC hydraulic cylinder system according to claim 1, wherein the following steps are included: the installation position of the inlet thickness gauge is used as an origin of a space coordinate system, the running direction of the steel plate is defined as a forward direction, and a one-dimensional space position tracking coordinate system is established; calculating the accumulated displacement of each micro element which moves along the rolling direction from the measurement moment to the current moment by adopting time integration according to the real-time running speed; subtracting the accumulated displacement from the fixed mounting distance from the inlet thickness gauge to the center line of the roll gap to obtain the residual travel of each infinitesimal distance from the current moment to the roll gap.
4. The rolling thickness compensation control method for the rolling mill based on the AGC hydraulic cylinder system, which is characterized in that the method for recording the microelements with the thickness measured value exceeding the allowable range as the microelements to be compensated and recording the thickness deviation comprises the following steps: determining a target thickness value and an allowable positive deviation upper limit and a allowable negative deviation lower limit according to the current rolled product specification; Comparing the measured thickness value of each infinitesimal with the target thickness value, calculating to obtain a thickness deviation amount, and judging that the infinitesimal has a compensation requirement when the thickness deviation amount exceeds the upper limit of positive deviation or is lower than the lower limit of negative deviation; The value and direction of the thickness deviation amount are recorded for the infinitesimal determined to be compensated.
5. The rolling thickness compensation control method for the rolling mill based on the AGC hydraulic cylinder system, which is characterized in that whether the rolling force response according to the preamble infinitesimal judges whether the rolling force response has the compensation necessity or not is judged according to the following implementation process: dividing the current steel plate into continuously numbered infinitesimal sequences along the length direction, collecting rolling force of each precursor infinitesimal after rolling is completed before entering a roll gap and after passing through the roll gap in real time, calculating the rolling force change rate, storing the rolling force change rate in a one-to-one correspondence manner with the thickness deviation amount of each precursor infinitesimal at an inlet side, and constructing a precursor infinitesimal response record set; When the data quantity in the response record set is smaller than the minimum sample quantity, directly judging that the current micro-element to be compensated has the necessity of compensation, and storing the rolling force change rate and the thickness deviation quantity in the response record set after the compensation is executed; when the data quantity in the response record set reaches the minimum sample quantity, for the current micro-element to be compensated in the list to be compensated, acquiring the thickness deviation quantity before the current micro-element enters a roll gap, and searching a plurality of precursor micro-elements with the difference value smaller than a preset tolerance range from the thickness deviation quantity of the current micro-element to be compensated in the precursor micro-element response record set as a reference micro-element set; the inverse number of the number difference between each reference micro element and the current micro element to be compensated is used for distributing weights for each reference micro element, linear weighting summation is carried out on the rolling force change rate corresponding to each reference micro element, and the calculated result is used as the predicted rolling force change rate of the current micro element to be compensated; And if the predicted value exceeds the abrupt threshold, keeping the record of the infinitesimal in the to-be-compensated list, otherwise, judging that the infinitesimal does not have the necessity of compensation, and removing the infinitesimal from the to-be-compensated list.
6. The rolling thickness compensation control method for the rolling mill based on the AGC hydraulic cylinder system, which is characterized in that the compensation triggering time is determined by the following implementation process: calculating the predicted residual time reaching the roll gap according to the current residual travel and the current real-time speed of each micro element to be compensated in the list to be compensated; Acquiring response delay time of the hydraulic servo system, and calculating a difference value between the residual time and the response delay time as delay time to be compensated for the primordia; when the time to be delayed is greater than zero, creating a timing task for the infinitesimal, and setting the timing duration as the time to be delayed; When the delay time is less than or equal to zero, the compensation instruction is immediately sent out.
7. The rolling thickness compensation control method of the rolling mill based on the AGC hydraulic cylinder system of claim 1, wherein the implementation process of generating the roll gap position adjustment quantity according to the thickness deviation quantity of the to-be-compensated primordial and superposing the roll gap position adjustment quantity to the roll gap set value is as follows: reading the thickness deviation amount of the element to be compensated from the list to be compensated, judging the compensation direction according to the positive sign and the negative sign of the thickness deviation amount, wherein the compensation direction is the roll gap reduction when the thickness deviation amount is positive value, and the compensation direction is the roll gap increase when the thickness deviation amount is negative value; Multiplying the thickness deviation by a pre-calibrated compensation coefficient to calculate and obtain the position adjustment quantity of the hydraulic cylinder; adding the calculated position adjustment quantity with the current roll gap set value to generate a new roll gap set target value as a hydraulic cylinder position control instruction; and sending a control voltage signal to the hydraulic servo valve according to the hydraulic cylinder position control command to drive the hydraulic cylinder piston to move to a new target position.
8. The rolling thickness compensation control method of the rolling mill based on the AGC hydraulic cylinder system, as set forth in claim 1, is characterized in that the judging process of the approaching compensation triggering time of the plurality of microelements to be compensated is as follows: monitoring the compensation triggering time of each element to be compensated in the list to be compensated in real time; when detecting that the difference value of the compensation trigger moments of more than two micro elements is smaller than the time approach limit value, judging that the compensation trigger moments of the micro elements are close.
9. The method for controlling rolling thickness compensation of a rolling mill based on an AGC hydraulic cylinder system according to claim 8, wherein the time-space cooperative processing of the multi-infinitesimal continuous compensation comprises the following steps: When the compensation triggering time of a plurality of micro elements to be compensated is judged to be close, further judging whether the numbers of the micro elements in the length direction of the steel plate are continuous or not, if yes, judging that the micro elements belong to the same continuous thickness abnormal section; performing arithmetic average calculation on the thickness deviation values of a plurality of microelements to be compensated belonging to the same continuous thickness abnormal section to obtain an average thickness deviation value; and calculating a unified position adjustment quantity by utilizing a pre-calibrated compensation coefficient according to the average thickness deviation quantity, and respectively executing compensation actions based on the unified position adjustment quantity when a plurality of microelements to be compensated sequentially pass through the roll gaps.
10. The method for controlling rolling thickness compensation of a rolling mill based on an AGC hydraulic cylinder system according to claim 9, wherein the time-space cooperative processing of the multi-infinitesimal continuous compensation further comprises the following steps: When the compensation triggering time of a plurality of micro elements to be compensated is close but the number is discontinuous, discrete thickness abnormal points of the micro elements belonging to different positions are judged; taking the time sequence of passing through the roll gaps of the microelements as nodes, and respectively calculating corresponding position adjustment amounts according to the thickness deviation amounts of the microelements; Generating continuous position adjustment instructions by adopting a linear interpolation method between two adjacent compensation trigger moments needing to be compensated for the infinitesimal; The generated position adjustment instruction sequence is discretized into a position increment instruction of each control period, and the position increment instruction is output to a hydraulic servo system for execution period by period, so that the roll gap is ensured to be adjusted to the required position when each element to be compensated reaches the roll gap.

Description

Rolling mill rolling thickness compensation control method based on AGC hydraulic cylinder system Technical Field The invention belongs to the technical field of rolling thickness compensation of rolling mills, and particularly discloses a rolling mill rolling thickness compensation control method based on an AGC hydraulic cylinder system. Background In the processing process of steel products, plate rolling is one of key procedures, the thickness precision after rolling directly determines the quality grade of the products, and due to uneven thickness of incoming materials, when a local thicker area enters a roll gap, rolling force can be increased instantaneously, rolling mill bouncing is caused, and the thickness of an outlet is out of tolerance. To suppress such disturbance, it is necessary to identify an inlet thickness abnormality before the steel sheet enters the roll gap and adjust the roll gap in advance. Therefore, the AGC system collects the thickness signal of the inlet by using a thickness gauge, dynamically adjusts and adjusts the roll gap of the rolling mill to compensate the thickness deviation of the incoming material, and ensures that the thickness of the outlet is stable within the tolerance range. However, the measured thickness signal inevitably has a transmission delay, limited by the physical installation distance existing between the inlet gauge and the mill gap. In order to cope with the problem, related solutions in the prior art, for example, chinese patent publication No. CN119525291B discloses a strip thickness control method based on thickness measurement value delay compensation, which is implemented by constructing a dynamic thickness transmission model considering the position deviation of a thickness gauge, introducing an inertia link to perform trend prediction on a thickness signal so as to compensate for the measurement delay, and on the basis, fusing a feedforward term for counteracting the rolling force bouncing effect and a proportional feedback term based on the predicted thickness deviation, generating a comprehensive roll gap setting instruction, and driving a hydraulic servo system to perform adjustment. However, the technical problems of the prior art still include that firstly, the scheme adopts a continuous signal processing frame, when the rolling speed is changed drastically, the moment when each position steel plate reaches the roll gap is difficult to map precisely, the triggering moment of the compensation command is mismatched with the actual physical position, and the time-space synchronism of the compensation action is affected. Secondly, the scheme directly triggers the compensation action only according to the predicted thickness deviation, and the verification of whether the thickness deviation actually causes the abnormal state of the rolling mill is not carried out, in actual production, part of thickness deviation possibly cannot cause obvious thickness out-of-tolerance due to factors such as the state of the rolling mill, material characteristics and the like, and the compensation of the deviation is redundant, and new disturbance can be introduced due to excessive adjustment. Disclosure of Invention In order to solve the technical problems or at least partially solve the technical problems, the invention provides a rolling thickness compensation control method of a rolling mill based on an AGC hydraulic cylinder system. The rolling thickness compensation control method of the rolling mill based on the AGC hydraulic cylinder system comprises the following steps of measuring the thickness and the running speed of a steel plate at an inlet of the rolling mill in real time, marking each thickness measuring point as a steel plate infinitesimal with a time sequence number, and tracking the residual travel of a roll gap of each infinitesimal distance. And marking the infinitesimal with the thickness measurement exceeding the allowable range as the infinitesimal to be compensated, recording the thickness deviation amount, and storing the serial number, the deviation amount and the residual travel of the infinitesimal to be compensated into a list to be compensated. And judging whether the compensation necessity exists for each element to be compensated according to the rolling force response of the leading element before entering the roll gap, and if not, removing from the list to be compensated. And processing the microelements to be compensated in sequence from the remaining travel to the large from the to-be-compensated list, and determining compensation triggering time according to the remaining travel and the response delay time of the hydraulic system. When compensation is triggered, a roll gap position adjustment quantity is generated according to the thickness deviation quantity of the micro elements to be compensated and is overlapped to a roll gap set value, a hydraulic cylinder is controlled by a hydraulic servo valve to execute compensation