A method and device for full-range micro-tension control of a continuous rolling mill

Abstract

The present application relates to a kind of full-range micro-tension control method for continuous rolling mill group, the continuous rolling mill group includes several racks, including the following steps: obtaining the rolling load data of the rack;According to the rolling load data of the rack, the small tension interval of the stable rolling between the rack is obtained;When the rolling between the rack is away from steady state, the control load of the rack is obtained by correcting the rolling load of the rack with the small tension interval range;From the perspective of free rolling torque, the tension relationship between each rack is deduced and decoupled, and an expert database system and a big data learning model are established in application, so that the rolling process can quickly enter the optimal rolling state, when external conditions change, timely adjustment can be made to maintain a constant tension rolling state, maximize product quality, more suitable for hot rolling strip, wire rod, profile and other production and processing, effectively avoiding the phenomenon of material stack pulling between racks.

Description

Technical Field

[0001] This invention relates to the field of continuous rolling mill technology, and more specifically to a method and device for full-process micro-tension control of continuous rolling mills. Background Technology

[0002] Tension control is a technology for automatically controlling the tension on a workpiece that is either in continuous motion or stationary between two processing machines. Tension control is mainly applied in roughing and intermediate rolling mills. For hot strip rolling lines, the main issues can be summarized as follows:

[0003] From an application perspective, most methods employ head tension control, which can be described as a method that uses the head changes of free load rolling torque and non-free load rolling torque to calculate the changes in inter-stand tension and provide the upstream stand speed adjustment amount. Head tension control, to some extent, hinders the changes in inter-stand tension.

[0004] If the rolling load and speed regime are properly allocated, tension control adjustment is beneficial to the system. However, if the allocation is unreasonable, tension control adjustment will have the opposite effect. Therefore, the method of adjusting the speed simply by changing the tension has drawbacks, because it calculates the increment of the tension between the stands, not the tension between the stands.

[0005] The premise for this control method to be valid is that the tension relationship generated by load distribution is within the allowable range, that is, the load distribution model under the low tension condition is satisfied.

[0006] Currently, tension control is rarely applied throughout the rolling process. The main problems are: First, the tension between stands is affected by all the continuous rolling stands, meaning the tension of one stand is influenced by the rolling load and tension of other continuous rolling stands, without proper decoupling. This means that adjusting the tension of one stand can negatively impact the tension of other stands, causing undesirable changes. Since strip rolling is affected by multiple factors such as temperature, cooling, material, specifications, and machinery, the rolling load cannot be perfectly accurate. This results in the objective existence of tension between stands, and strictly speaking, the situation is different for each strip. Therefore, this increases the difficulty of real-time control throughout the process, because: first, it can have a counterproductive effect; second, calculating real-time tension is challenging; and third, selecting a control strategy is not easy, as real-time adjustments can cause fluctuations and oscillations, which are detrimental to rolling and equipment safety. Summary of the Invention

[0007] The purpose of this invention is to provide a method and device for full-process micro-tension control of continuous rolling mills, aiming to solve the problem of high difficulty and poor effect in real-time tension control of continuous rolling mills in the prior art.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] One approach provides a method for full-process micro-tension control in a continuous rolling mill, the continuous rolling mill comprising several stands, including the following steps:

[0010] Obtain the rolling load data of the stand;

[0011] The small tension range for stable rolling between the stands is obtained based on the rolling load data of the stands;

[0012] When the rolling between the stands deviates from a steady state, the rolling load of the stand is corrected within the small tension range to obtain the control load of the stand.

[0013] More preferably, when the rolling between the stands deviates from a steady state, the step of correcting the rolling load of the stand within the small tension range to obtain the control load of the stand includes:

[0014] The margin range for the change of small tension trend between the stands is obtained based on the small tension range of stable rolling between the stands;

[0015] When the small tension between the stands changes in a trend, the rolling load of the stands is corrected within the margin range.

[0016] More preferably, when the rolling between the stands deviates from a steady state, the step of correcting the rolling load of the stand within the small tension range to obtain the control load of the stand further includes:

[0017] The hysteresis range of the transition change between the stands is obtained based on the small tension range of the stable rolling between the stands;

[0018] When the steady-state change of the small tension between the frames is accelerated, the range of the hysteresis interval is reduced;

[0019] When the steady-state change of the small tension between the frames is slowed down, the range of the hysteresis interval is increased.

[0020] More preferably, obtaining the low-tension range for stable rolling between the stands based on the rolling load data of the stands includes:

[0021] Rolling correlation data is obtained based on the rolling load data of the stand using a big data multiple linear regression algorithm;

[0022] The low tension range for stable rolling between stands is obtained by referencing and correcting the rolling correlation data.

[0023] More preferably, obtaining the low-tension range for stable rolling between the stands based on the rolling load data of the stands further includes:

[0024] Receive rolling information from the expert experience database;

[0025] The low tension range for stable rolling between stands is obtained by referencing and correcting the rolling information.

[0026] More preferably, obtaining the rolling load data of the stand includes:

[0027] Obtain the resultant torque, reduction ratio, and roll diameter for each frame;

[0028] The free load torque of each frame other than the first frame is calculated based on the free load torque of the first frame, the resultant torque of each frame, the reduction ratio of each frame, and the roll diameter of each frame.

[0029] The rolling load of each stand is calculated based on the free load torque of each stand and the torque arm length of each stand.

[0030] More preferably, the calculation expression for the free load torque of each frame is shown in equation (1):

[0031]

[0032] Where i is a natural number greater than 1, m is a natural number satisfying 1 ≤ m ≤ i - 1; M 0i M represents the free load torque of the i-th frame; Σi This represents the resultant torque of the i-th frame;

[0033] In equation (1), a i The calculation expression is shown in equation (2):

[0034]

[0035] Among them, i i D represents the reduction ratio of the i-th frame; i This represents the diameter of the rolls in the i-th frame.

[0036] More preferably, the rolling load calculation expression for each stand is shown in equation (3):

[0037]

[0038] Where, r i This represents the torque arm length of the i-th frame.

[0039] More preferably, the expression for calculating the tension between the frames is shown in equation (4):

[0040] f i(i+1)=f (i-1)i +a i (M Σi -M 0i ) = a i+1 (M Σ(i+1) -M 0(i+1) (4)

[0041] Among them, f i(i+1) This represents the tension between the i-th rack and the (i+1)-th rack;

[0042] The rolling load is distributed to the stands based on the minimum tension between the stands, and the load distribution relationship is expressed as shown in equation (5):

[0043] f(b1, ..., b) i )=0 (5)

[0044] On the other hand, a full-process micro-tension control system for a continuous rolling mill is provided, the full-process micro-tension control system including at least one processor; and a memory storing instructions that, when executed by the at least one processor, implement the steps of the method described above.

[0045] The beneficial effects of this invention lie in its ability to reverse-engineer and decouple the tension relationship between stands from the perspective of free rolling torque. Furthermore, it establishes an expert database system and a big data learning model, enabling the rolling process to quickly reach its optimal rolling state. When external conditions change, it can make timely adjustments to maintain a constant tension rolling state, maximizing product quality. This invention is more suitable for the production and processing of hot-rolled strip, wire rod, and profiles. It also includes an intelligent module that uses big data analysis to automatically and timely adjust to changes in external conditions, ensuring stable tension rolling, effectively avoiding material accumulation between stands, improving product quality, and reducing reliance on operator skills. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the full-process micro-tension control system in this invention;

[0047] Figure 2 This is a schematic diagram of the whole-process micro-tension control structure in this invention;

[0048] Figure 3 This is a schematic diagram of the micro-tension control steps throughout the entire process in this invention;

[0049] Figure 4 This is a schematic diagram of the structure of a continuous rolling mill in the prior art of this invention. Detailed Implementation

[0050] The technical solution of the present invention will now be clearly and completely described in conjunction with the accompanying drawings and embodiments.

[0051] In the current technology, a schematic diagram of the operation of a continuous rolling mill is shown below. Figure 4 As shown, the continuous rolling mill operates from left to right. Its main working principle is to roll raw materials of a certain length, width, and thickness into products of a certain length, width, and thickness by utilizing the equal flow rate of billets passing through the mills per second. Assuming the billet passing through F1 has a thickness of H1, a width of W1, and a speed of V1, the billet passing through F2 has a thickness of H2, a width of W2, and a speed of V2, and the billet passing through F3 has a thickness of H3, a width of W3, and a speed of V3, then the amount of material passing through mills F1, F2, and F3 per unit time is equal, meaning the flow rate per second is equal. This leads to the formula: W1*H1*V1=W2*H2*V2=W3*H3*V3. Using this theoretical basis, the load, roll gap, and speed of each mill can be determined based on the incoming material specifications, target specifications, and the number of mills.

[0052] In a continuous rolling mill, the load distribution of each stand is usually determined based on the principle of balancing working rolling forces.

[0053] In a continuous rolling mill, each stand bears a portion of the rolling force, which is transmitted from the upstream stand to the downstream stand. The goal of stand load distribution is to ensure that each stand bears a relatively balanced rolling force, thereby achieving continuous rolling of the material.

[0054] Normally, the load is evenly distributed or weighted according to the design and process requirements of the rolling equipment.

[0055] 1. Uniform Distribution: Distribute the remaining rolling load evenly across each stand. If there are n remaining stands, the load on each stand is the rolling load divided by the number of remaining stands.

[0056] 2. Weighting: Different weights are assigned to each rack based on its capacity and load-bearing capacity. Stronger racks bear more load, while weaker racks bear less load. Weights can be set according to actual needs.

[0057] There are generally two methods for verifying assignment relationships:

[0058] 1. Theoretical Calculation: Based on the load distribution relationship and the load-bearing capacity of the racks, the load borne by each rack can be theoretically calculated. The load of each rack can be calculated using load distribution formulas based on given loads and weights.

[0059] 2. Actual Measurement Verification: The load distribution relationship is verified by measuring the load on each rack during actual production. Sensors or pressure measuring instruments can be used to obtain load data for each rack, and the results are compared with theoretical calculations.

[0060] The above methods can be used to derive and verify the rolling load of the remaining stands, ensuring the rationality and accuracy of load allocation. It should be noted that the actual load allocation method may vary depending on specific circumstances and needs to be adjusted and optimized according to actual requirements and equipment parameters.

[0061] Some embodiments of the present invention relate to a full-process micro-tension control system for continuous rolling mills, such as... Figure 1 As shown, the full-process micro-tension control system 1 includes at least one processor 2; and a memory 3 that stores instructions, which, when executed by at least one processor 2, are used to implement all the steps in the following method implementation.

[0062] Some embodiments of the present invention also relate to a method for full-process micro-tension control of a continuous rolling mill, the continuous rolling mill comprising a plurality of stands, comprising the following steps:

[0063] Obtain the rolling load data of the stand;

[0064] The small tension range for stable rolling between the stands is obtained based on the rolling load data of the stands;

[0065] When the rolling between the stands deviates from a steady state, the rolling load of the stand is corrected within the small tension range to obtain the control load of the stand.

[0066] In some implementations of the full-process micro-tension control method for continuous rolling mills, when the rolling between the stands deviates from a steady state, the control load of the stand is obtained by correcting the rolling load of the stand within the small tension range, including:

[0067] The margin range for the change of small tension trend between the stands is obtained based on the small tension range of stable rolling between the stands;

[0068] When the small tension between the stands changes in a trend, the rolling load of the stands is corrected within the margin range.

[0069] In some implementations of the full-process micro-tension control method for continuous rolling mills, when the rolling between the stands deviates from a steady state, the control load of the stand is obtained by correcting the rolling load of the stand within the small tension range, which further includes:

[0070] The hysteresis range of the transition change between the stands is obtained based on the small tension range of the stable rolling between the stands;

[0071] When the steady-state change of the small tension between the frames is accelerated, the range of the hysteresis interval is reduced;

[0072] When the steady-state change of the small tension between the frames is slowed down, the range of the hysteresis interval is increased.

[0073] In some implementations of the full-process micro-tension control method for continuous rolling mills, obtaining the low-tension range for stable rolling between the stands based on the rolling load data of the stands includes:

[0074] Rolling correlation data is obtained based on the rolling load data of the stand using a big data multiple linear regression algorithm;

[0075] The low tension range for stable rolling between stands is obtained by referencing and correcting the rolling correlation data.

[0076] By analyzing the relevant data, a reference correction for the model is provided. An online multiple linear regression algorithm is adopted, which effectively solves the model specification error and improves the model accuracy.

[0077] Multiple linear regression analysis is a statistical analysis method that predicts or explains changes in the dependent variable by establishing a linear relationship between two or more independent variables and a continuous dependent variable. Its basic formula can be expressed as:

[0078] Y = a + b1X1 + b2X2 + ... + b n X n +∈

[0079] Where Y is the dependent variable, X1-X n The independent variable is 'a', where 'a' is the intercept and 'b' is '1-b'. n ∈ represents the regression coefficient, and ∈ represents the error term.

[0080] The main assumptions of this model include:

[0081] 1. Linear relationship: The relationship between variables can be described using a linear model.

[0082] 2. Independent observation: Each observation is observed independently, and there is no autocorrelation between the data.

[0083] 3. Homoscedasticity: The variance of all independent variables should be constant, that is, the dispersion of the data should not change with the level of the independent variables.

[0084] 4. Normality: The values ​​of the dependent variable should be normally distributed.

[0085] In practical applications, we typically use the least squares method to estimate regression coefficients. This method obtains the estimate by minimizing the sum of squared errors between the predicted and actual values ​​for each observation.

[0086] The advantages of multiple linear regression models are their ease of understanding and interpretation, and their relative simplicity in computation. However, their main drawback is that they may overlook complex interactions between some variables.

[0087] Multiple linear regression analysis is widely used in many fields, including economics, biology, engineering, medicine, and social sciences. For example, economists might use this analysis to predict future economic growth, engineers might use it to optimize manufacturing processes, and medical researchers might use it to understand how different factors influence health outcomes.

[0088] In some implementations of the full-process micro-tension control method for continuous rolling mills, obtaining the small tension range for stable rolling between the stands based on the rolling load data of the stands further includes:

[0089] Receive rolling information from the expert experience database;

[0090] The low tension range for stable rolling between stands is obtained by referencing and correcting the rolling information.

[0091] The expert experience integrates mature and effective field experience to form a library model system under different conditions. It integrates highly coupled relevant data, triggers corresponding solutions under different problem conditions, and provides a useful supplement to the process control system.

[0092] In some implementations of the full-process micro-tension control method for continuous rolling mills, obtaining the rolling load data of the stand includes:

[0093] Obtain the resultant torque, reduction ratio, and roll diameter for each frame;

[0094] The free load torque of each frame other than the first frame is calculated based on the free load torque of the first frame, the resultant torque of each frame, the reduction ratio of each frame, and the roll diameter of each frame.

[0095] The rolling load of each stand is calculated based on the free load torque of each stand and the torque arm length of each stand.

[0096] In some implementations of the full-process micro-tension control method for continuous rolling mills, the calculation expression for the free load torque of each stand is shown in equation (1):

[0097]

[0098] Where i is a natural number greater than 1, m is a natural number satisfying 1 ≤ m ≤ i - 1; M 0i M represents the free load torque of the i-th frame; ΣiThis represents the resultant torque of the i-th frame;

[0099] In equation (1), a i The calculation expression is shown in equation (2):

[0100]

[0101] Among them, i i D represents the reduction ratio of the i-th frame; i This represents the diameter of the rolls in the i-th frame.

[0102] In some implementation methods for full-process micro-tension control of continuous rolling mills, the calculation expression for the rolling load of each stand is shown in equation (3):

[0103]

[0104] Where, r i This represents the torque arm length of the i-th frame.

[0105] In some implementation methods for full-process micro-tension control of continuous rolling mills, the tension calculation expression between stands is shown in equation (4):

[0106] f i(i+1) =f (i-1)i +a i (M Σi -M 0i ) = a i+1 (M Σ(i+1) -M 0(i+1) (4)

[0107] Among them, f i(i+1) This represents the tension between the i-th rack and the (i+1)-th rack;

[0108] The rolling load is distributed to the stands based on the minimum tension between the stands, and the load distribution relationship is expressed as shown in equation (5):

[0109] f(b1, ..., b) i )=0 (5)

[0110] Specifically, the load distribution relationship of each rack can be determined by the following principle:

[0111] 1. Rolling Force Balance: In a continuous rolling mill, the rolling force transmitted from the upstream stand to the downstream stand should be equal to the rolling force of the downstream stand. This can be achieved by using a transfer device (such as a roller conveyor) between the stands.

[0112] 2. Torque balance: Free load torque M of each frame 0i With rolling load b iThere is a certain relationship between them. Ideally, the free load torque of each rack should be zero.

[0113] In summary, the load distribution relationship of each stand in a continuous rolling mill can be expressed as a combination of a force balance equation and a moment balance equation, where the force balance equation ensures the balance of rolling forces and the moment balance equation ensures the balance of free load torques.

[0114] The specific load distribution formula can be determined based on the specific frame structure and operating parameters, generally taking into account factors such as frame rigidity, roller conveyor elasticity, and workpiece deformation. The formula is f(b1, ..., b...). i The meaning of ) = 0 is that, under ideal conditions, the free load torque is zero and the rolling force load is also zero.

[0115] In some implementation methods for full-process micro-tension control of continuous rolling mills, the calculation principles for free rolling torque and inter-stand tension are as follows:

[0116] The effects of inter-rack tension on the upstream and downstream racks are opposite. Taking the upstream rack as the reference, the effect on the upstream rack is defined as a positive action (+), while the effect on the downstream rack is a negative action (-).

[0117] Let M Σi M is the sum of the torques of the i-th frame, which is the actual torque of the motor. i f is the free load moment of the i-th frame. i(i+1) For the tension between the i-th rack and the (i+1)-th rack, based on the relationship between the incremental tension torque and the tension between racks...

[0118]

[0119] In the case of a model, different numbers of continuous rolling mill stands can be considered separately. The tension torque generated by the tension between the upstream and downstream stands varies with the roll diameter and reduction ratio. That is, for different stands, the tension and tension torque are the same, but the tension torque is different. Therefore, it is more reasonable to express the tension torque in the equation system as an expression for the tension.

[0120] The calculation of free load torque is based on the free torque of the sampling stand (first stand). The following is the calculation of free rolling load torque, which is explained in four cases:

[0121] M 01 This is the measured value of the free load torque of the first stand before continuous rolling.

[0122] Case with 2 racks:

[0123]

[0124] In the formula, ΔM1 and ΔM2 represent the tension torques generated between the frames on the front and rear frames, where...

[0125]

[0126] Transforming the above equation yields... Where the definition

[0127] Thus, the free load torque M of the second frame can be obtained. 02

[0128]

[0129] After obtaining the free load torque of the second stand, the change in tension between the stands can be calculated based on the real-time change in rolling torque.

[0130] The case with 3 racks:

[0131] For the three-rack configuration, the following relationship holds:

[0132]

[0133] Calculation yields:

[0134] f 23 =f 12 +a2(M Σ2 -M 02 )=a1(M Σ1 -M 01 )+a2(M Σ2 -M 02 )

[0135] =a3(M Σ3 -M 03 )

[0136] The free load torque of the third frame can be obtained:

[0137]

[0138] Case with 4 racks:

[0139]

[0140] The calculation yields:

[0141]

[0142] The free load torque of the fourth frame can be obtained:

[0143]

[0144] Similarly, we can calculate:

[0145]

[0146] In some methods for full-process micro-tension control of continuous rolling mills, the correction of process model load distribution is as follows:

[0147] Given the existence of a model, under the condition of free rolling on the first stand, the free rolling load torque of the remaining continuous rolling stands can be calculated by sampling the stands. Based on the load distribution relationship of each stand, the model rolling load of the remaining stands can be derived and verified, and the correction of the model rolling load can be given online to achieve the optimal load distribution relationship.

[0148] After the load is adjusted, the rolling load of a stand that forms a continuous rolling pattern with the upstream stand will change. After forming a continuous rolling pattern with the downstream stand, the rolling load will also change to reflect the tension relationship under different continuous rolling conditions.

[0149] A certain rolling load relationship corresponds to a defined tension between stands. If the minimum tension (zero tension) is used as the benchmark (cost function) for the load distribution of the rolling mill, the stacking tension relationship between stands will be minimized, resulting in excellent load distribution and minimal speed adjustment.

[0150] The expression for the tension between each frame is calculated by solving the system of equations. Under the condition of minimum tension, i.e., f i(i+1) =0

[0151] That is, the load distribution relationship under pressure satisfies f(b1, ..., b) i )=0 condition.

[0152] In some implementation methods for full-process micro-tension control in continuous rolling mills, the process control strategy is as follows:

[0153] Tension control is guided by two principles: the principle of minimum tension and the principle of stable rolling. Minimum tension implies the uniformity and optimality of the rolling load. If the principle of minimum tension is met, stable rolling will inevitably occur. Stable rolling indicates that the stacking relationship between the stands is appropriate, that is, the exit speed equals the inlet speed, which means the tension is zero. This indicates that stable rolling must be minimum tension rolling.

[0154] Of course, the rolling process is affected by many factors and is not static. The entire rolling process is a continuous transition from one steady-state range to another. If this transition cannot be completed, the rolling will become unstable rolling. When it leaves the stable tension range of rolling, it will cause serious steel piling or steel pulling, which will seriously affect the width and thickness of the product and may even cause scrap steel.

[0155] The purpose of tension control is to find a stable tension range for rolling. When rolling deviates from a stable state, the control quantity can promptly pull the tension between stands back into the stable tension range. This control approach avoids real-time adjustments while ensuring speed.

[0156] The prerequisite for tension control is the accurate judgment of the tension change trend between stands. When the tension does indeed change in a trend, the allowable margin for tension change is found, and the control quantity is given in a step-like manner according to this range to achieve the purpose of minimum tension rolling.

[0157] Setting a redundancy range for low-tension control can be called a hysteresis range. This range is set according to actual adjustment needs, indicating transitions in the direction of tension increase and decrease. If the steady-state change needs to be accelerated, the hysteresis range should be reduced; conversely, it should be increased. The main purpose of setting a hysteresis range is to improve control stability, which is beneficial for the stability of trend-based adjustments.

[0158] In some implementation methods for full-process micro-tension control in continuous rolling mills, the intelligent analysis of data is as follows:

[0159] The intelligent module for process control mainly accomplishes the following two tasks: first, establishing an expert experience database; and second, establishing a big data-driven model.

[0160] The expert experience integrates mature and effective field experience to form a library model system under different conditions. It integrates highly coupled relevant data, triggers corresponding solutions under different problem conditions, and provides a useful supplement to the process control system.

[0161] Big data-driven models provide reference corrections for the established models through the analysis of related data. The big data model adopts an online multiple linear regression algorithm, which effectively solves the model specification error and improves the model accuracy.

[0162] The embodiments and functional operations of the subject matter described in this specification can be implemented in the following ways: digital electronic circuits, tangibly implemented computer software or firmware, computer hardware, including the structures disclosed in this specification and their equivalents, or combinations thereof. Embodiments of the subject matter described in this specification can be implemented as one or more computer programs, that is, one or more modules of computer program instructions encoded on one or more tangible non-transitory program carriers, for execution by a data processing device or to control the operation of the data processing device.

[0163] Alternatively or additionally, program instructions may be encoded on artificially generated propagation signals, such as machine-generated electrical, optical, or electromagnetic signals, which are then generated as coded information to be transmitted to an appropriate receiver device executed by data processing equipment. The computer storage medium may be a machine-readable storage device, a machine-readable storage substrate, a random or serial access memory device, or one or more combinations of the above.

[0164] The term "data processing device" encompasses all kinds of devices, apparatuses, and machines used for processing data, including, for example, programmable processors, computers, or multiprocessor systems or multicomputer systems. Devices may include special-purpose logic circuitry, such as FPGAs (Field-Programmable Gate Arrays) or ASICs (Application-Specific Integrated Circuits). In addition to hardware, devices may also include code that creates the execution environment for associated computer programs, such as processor firmware, protocol stacks, database management systems, operating systems, or combinations thereof.

Claims

1. A method for full-process micro-tension control in a continuous rolling mill, the continuous rolling mill comprising several stands, characterized in that, Includes the following steps: Obtaining the rolling load data of the stands includes: obtaining the resultant torque, reduction ratio, and roll diameter of each stand; calculating the free load torque of each stand other than the first stand based on the free load torque of the first stand, the resultant torque of each stand, the reduction ratio of each stand, and the roll diameter of each stand; and calculating the rolling load of each stand based on the free load torque of each stand and the torque arm length of each stand. The method for obtaining the low-tension range for stable rolling between stands based on the rolling load data of the stands includes: obtaining rolling correlation data based on the rolling load data of the stands using a big data multiple linear regression algorithm; obtaining the low-tension range for stable rolling between stands by performing reference correction based on the rolling correlation data; and further includes: receiving rolling information sent from an expert experience database; obtaining the low-tension range for stable rolling between stands by performing reference correction based on the rolling information. When the inter-stand rolling deviates from a steady state, the rolling load of the stand is corrected using the small tension range to obtain the control load of the stand. This includes: obtaining a margin range for the trend change of the small tension between the stands based on the small tension range of the stable inter-stand rolling; correcting the rolling load of the stand using the margin range when the small tension between the stands undergoes a trend change; further including: obtaining a hysteresis range for the transitional change of the small tension between the stands based on the small tension range of the stable inter-stand rolling; reducing the range of the hysteresis range when accelerating the steady-state change of the small tension between the stands; and increasing the range of the hysteresis range when slowing down the steady-state change of the small tension between the stands.

2. The method for full-process micro-tension control of a continuous rolling mill according to claim 1, characterized in that, The calculation expression for the free load torque of each of the remaining frames excluding the first frame is as shown in equation (1). As shown: Where i is a natural number greater than 1, m is a natural number satisfying 1 ≤ m ≤ i - 1; M 0i M represents the free load torque of the i-th frame; Σi M represents the resultant torque of the i-th frame; Σ1 M represents the resultant torque of the first frame; 01 This indicates that the first stand has not generated free load torque for continuous rolling; In equation (1), a i The calculation expression is shown in equation (2): Among them, i i D represents the reduction ratio of the i-th frame; i This represents the diameter of the rolls in the i-th frame.

3. The method for full-process micro-tension control of a continuous rolling mill according to claim 2, characterized in that, The calculation expression for the rolling load of each stand is shown in equation (3): Where, r i This represents the torque arm length of the i-th frame.

4. The method for full-process micro-tension control of a continuous rolling mill according to claim 3, characterized in that, The expression for calculating the tension between the frames is shown in equation (4): f i(i+1) =f (i-1)i +a i (M Σi -M 0i ) = a i+1 (M Σ(i+1) -M 0(i+1) (4) Where, f i(i+1) f represents the tension between the i-th rack and the (i+1)-th rack; (i-1)i This represents the tension between the (i-1)th frame and the ith frame; The rolling load is distributed to the stands based on the minimum tension between the stands, and the load distribution relationship is expressed as shown in equation (5): f(b1,…,b i )=0 (5).

5. A full-process micro-tension control system for continuous rolling mills, characterized in that, The full-range micro-tension control system includes at least one processor; and a memory storing instructions that, when executed by the at least one processor, perform the steps of the method according to any one of claims 1-4.

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