Method and device for controlling strip temperature during dynamic gauge change stage in strip continuous annealing process

Abstract

The application provides a strip steel continuous annealing process dynamic variable gauge stage plate temperature control method and device, the method comprises the following steps: obtaining the actual production parameter group, batch history sample and historical heating section radiation coefficient in the dynamic variable gauge stage of the strip steel continuous annealing process, the actual production parameter group comprises the actual production parameters of the heating furnace length, actual furnace temperature, actual strip steel speed, main coiled strip steel, secondary coiled strip steel, and the position of the strip steel weld between the main coiled strip steel and the secondary coiled strip steel; using the batch history sample, the historical heating section radiation coefficient, the actual strip steel speed and the actual production parameters of the main coiled strip steel to obtain the corrected heating section radiation coefficient; and completing the plate temperature control according to the corrected heating section radiation coefficient and the actual production parameter group. The application can improve the precision of the plate temperature control in the dynamic variable gauge stage of the strip steel continuous annealing process on the basis of ensuring the plate temperature control efficiency in the dynamic variable gauge stage of the strip steel continuous annealing process.

Description

Technical Field

[0001] This application relates to the field of metallurgical technology, and in particular to a method and device for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing. Background Technology

[0002] In continuous annealing production, strip steel needs to undergo precise heat treatment in a heating furnace to obtain the target microstructure and properties. The key lies in the precise control of the strip temperature (i.e., the temperature of the strip itself). Due to the strong radiative and convective heat transfer relationship between the heating furnace and the strip, and the significant thermal inertia of the system, when the strip specifications change dynamically during production (such as changes in thickness, width, or steel grade), the physical parameters of the preceding and following coils of strip require different combinations of furnace temperature and strip speed, making temperature control in the transition zone (especially near the weld) extremely difficult.

[0003] Traditional control methods often rely on plate thermometers installed at the furnace outlet for closed-loop feedback regulation. However, plate thermometers are easily affected by dust and moisture in the field, and there are limitations in installation location and response delays, resulting in lagging and distorted measurement values. They are difficult to accurately reflect the real-time temperature status of the strip steel in the furnace, which in turn leads to inaccurate control commands. Summary of the Invention

[0004] To address at least one problem in the prior art, this application proposes a method that can improve the accuracy of temperature control during the dynamic specification change stage of strip annealing while ensuring the efficiency of temperature control during this stage.

[0005] To address the aforementioned technical problems, this application provides the following technical solution: In a first aspect, this application provides a method for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing, including: The actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients are obtained during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip weld between the main coil strip steel and the secondary coil strip steel. The corrected heating section radiation coefficient is obtained by using a batch of historical samples, their respective historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coiled strip. Based on the corrected heating section radiation coefficient and the actual production parameter set, the plate temperature control of the main strip steel is completed.

[0006] In one embodiment, obtaining the corrected heating section radiation coefficient using batch historical samples, their respective corresponding historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coiled strip includes: The stability coefficient is obtained by using a batch of historical samples, the actual strip speed, and the strip thickness in the actual production parameters of the main coil strip. The historical reference radiation coefficient is obtained based on the historical heating segment radiation coefficient and sample weight corresponding to each historical sample. The corrected heating section radiation coefficient is obtained based on the stability coefficient, the historical reference radiation coefficient, and the preset first initial heating section radiation coefficient.

[0007] In one embodiment, the strip temperature control method during the dynamic specification change stage of the strip annealing process further includes: Based on the preset original furnace temperature and plate temperature relationship model, the length of the heating furnace, and the historical samples, the radiation coefficient of the historical heating section corresponding to the historical samples is determined.

[0008] In one embodiment, determining the historical heating section radiation coefficient corresponding to the historical sample based on a preset original furnace temperature and plate temperature relationship model, the furnace length, and the historical sample includes: The preset second initial historical heating section radiation coefficient is used as the heating section radiation coefficient in the preset original furnace temperature and plate temperature relationship model. The first iteration step is executed, which includes: obtaining the historical strip steel predicted plate temperature at the furnace outlet corresponding to the historical sample based on the preset original furnace temperature and plate temperature relationship model, the furnace length and the historical sample. Determine whether the predicted plate temperature of the historical strip steel meets the preset plate temperature requirement. If so, determine the heating section radiation coefficient in the current preset original furnace temperature and plate temperature relationship model as the historical heating section radiation coefficient corresponding to the historical sample. Otherwise, adjust the heating section radiation coefficient in the preset original furnace temperature and plate temperature relationship model and execute the first iteration step again.

[0009] In one embodiment, each of the historical samples includes: historical strip temperature and historical production parameters, which include: historical furnace temperature, historical strip quality, working area, speed, corresponding comprehensive radiation coefficient and protective gas correction coefficient; Correspondingly, the step of obtaining the historical predicted strip temperature at the furnace outlet corresponding to the historical sample based on the preset original furnace temperature and strip temperature relationship model, the furnace length, and the historical sample includes: The number of heating process steps is determined based on the length of the heating furnace and the speed of the historical strip steel. The historical strip temperature is used as the strip temperature before heating in the current time step. The second iteration step includes: inputting the historical production parameters and the strip temperature before heating in the current time step into the preset original furnace temperature and plate temperature relationship model to obtain the strip temperature before heating in the next time step. Determine whether the number of times the second iteration step has been executed has reached the number of heating process steps. If so, determine the strip temperature before heating in the next time step as the historical predicted strip temperature. Otherwise, take the strip temperature before heating in the next time step as the strip temperature before heating in the current time step and execute the second iteration step again.

[0010] In one embodiment, the step of controlling the plate temperature of the main strip steel based on the corrected heating section radiation coefficient and the actual production parameter set includes: Based on the actual strip speed and the position of the strip weld, it is determined whether the estimated time from the strip weld to the furnace inlet is less than the preset time. If so, the main strip coil is determined to be the previous strip coil, and the secondary strip coil is determined to be the next strip coil. Based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main strip coil, and the corrected heating section radiation coefficient, the target strip speed is obtained. The actual strip speed is adjusted to the target strip speed to complete the plate temperature control of the main strip coil. If the estimated time taken is greater than or equal to the preset time and the strip thickness of the previous and subsequent coils is different, then the strip with the higher preset priority among the previous and subsequent coils is determined as the primary coil, and the strip with the lower preset priority is determined as the secondary coil. Based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the primary coil, and the corrected heating section radiation coefficient, the target furnace temperature is obtained, and the actual furnace temperature is adjusted to the target furnace temperature to complete the plate temperature control of the primary coil. If the estimated time taken is greater than or equal to the preset time and the strip thickness of the previous and subsequent coils is the same, then the primary coil is determined to be the previous coil and the secondary coil to be the subsequent coil. Based on the preset process settings, the furnace length, the actual furnace temperature, the actual strip speed, the actual production parameters of the primary coil, and the corrected heating section radiation coefficient, the target furnace temperature is obtained, and the actual furnace temperature is adjusted to the target furnace temperature to complete the plate temperature control of the primary coil.

[0011] In one embodiment, obtaining the target strip speed based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main coil strip, and the corrected heating section radiation coefficient includes: Using the actual strip speed as a speed parameter, the third iteration step is executed. The third iteration step includes: predicting the predicted strip temperature at the outlet of the heating furnace based on the heating furnace length, actual furnace temperature, speed parameter, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model. Determine whether the predicted strip temperature has reached the preset strip temperature requirement. If so, determine the current speed parameter as the target strip speed; otherwise, adjust the speed parameter and execute the third iteration step again.

[0012] In one embodiment, obtaining the target furnace temperature based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main coil strip, and the corrected heating section radiation coefficient includes: Using the actual furnace temperature as the furnace temperature parameter, the fourth iteration step is executed. The fourth iteration step includes: predicting the predicted strip temperature at the furnace outlet based on the furnace length, actual furnace temperature, furnace temperature parameter, actual strip speed, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model. Determine whether the predicted strip temperature has reached the preset temperature requirement. If so, set the current furnace temperature parameter as the target furnace temperature; otherwise, adjust the furnace temperature parameter and execute the fourth iteration step again.

[0013] In one embodiment, obtaining the target furnace temperature based on preset process settings, the furnace length, the actual furnace temperature, the actual strip speed, the actual production parameters of the main coil strip, and the corrected heating section radiation coefficient includes: The ratio of the preset process setting value to the strip thickness is determined as the set strip speed; Using the actual furnace temperature as the furnace temperature parameter, the fifth iteration step is executed. The fifth iteration step includes: predicting the predicted strip temperature at the furnace outlet based on the furnace length, actual furnace temperature, furnace temperature parameter, set strip speed, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model. Determine whether the predicted strip temperature has reached the preset temperature requirement. If so, the current furnace temperature parameter is determined as the target furnace temperature; otherwise, adjust the furnace temperature parameter and execute the fifth iteration step again.

[0014] Secondly, this application provides a strip temperature control device for the dynamic specification change stage during continuous strip annealing, comprising: The acquisition module is used to acquire the actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip weld between the main coil strip steel and the secondary coil strip steel. The correction module is used to obtain the corrected heating section radiation coefficient by utilizing a batch of historical samples, their respective historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coil strip. The control module is used to control the plate temperature of the main strip steel according to the corrected heating section radiation coefficient and the actual production parameter set.

[0015] Thirdly, this application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the plate temperature control method for the dynamic specification change stage during the continuous annealing of strip steel.

[0016] Fourthly, this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the plate temperature control method for the dynamic specification-changing stage during the continuous strip annealing process.

[0017] Fifthly, this application provides a computer program product, which includes a computer program that, when executed by a processor, implements the plate temperature control method for the dynamic specification change stage during the continuous strip annealing process.

[0018] As can be seen from the above technical solution, this application provides a method and device for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing, which improves the accuracy of plate temperature control during the dynamic specification change stage of strip steel continuous annealing while ensuring the efficiency of plate temperature control during the dynamic specification change stage of strip steel continuous annealing. Specifically, a plate temperature and furnace temperature relationship model can be established using mechanistic models and empirical parameters. This allows for the pre-calculation of corresponding furnace temperature parameters and speed requirements during the transition control process of changing specifications. Parameters can be switched appropriately in real-world conditions to achieve stable plate temperature control during both steady-state and transitional phases, improving the strip yield during the transition process. Coupled with the distribution of furnace temperature parameters, plate temperature parameters, and production speed, this method eliminates control inaccuracies caused by inaccurate temperature gauge measurements compared to traditional closed-loop plate temperature control, and also improves control speed. Furthermore, the offline basic radiation coefficient can be corrected online based on the current weld position, strip thickness, strip speed, and recent historical samples, making the furnace temperature and plate temperature relationship model more closely reflect the current actual heat exchange state. This improves the accuracy of plate temperature prediction and furnace temperature / speed setting calculations during dynamic specification changes, and reduces plate temperature fluctuations during weld and specification switching phases. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a first flowchart illustrating the plate temperature control method during the dynamic specification change stage of strip steel continuous annealing in the embodiments of this application. Figure 2 This is a second flowchart illustrating the plate temperature control method during the dynamic specification change stage of strip steel continuous annealing in the embodiments of this application. Figure 3 This is a schematic diagram of the third process of the strip temperature control method during the dynamic specification change stage in the continuous annealing of strip steel in the embodiments of this application. Figure 4 This is a schematic diagram of the fourth process of the strip temperature control method during the dynamic specification change stage in the continuous annealing of strip steel in the embodiments of this application. Figure 5 This is the fifth flowchart of the strip temperature control method during the dynamic specification change stage in the continuous annealing process of strip steel in the embodiments of this application; Figure 6 This is a schematic diagram of the control flow in a specific application example of this application; Figure 7This is a schematic diagram of the plate temperature control device during the dynamic specification change stage of the strip steel continuous annealing process in the embodiments of this application; Figure 8 This is a schematic block diagram of the system configuration of an electronic device according to an embodiment of this application. Detailed Implementation

[0020] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] To address the problem of inconsistent strip temperatures during dynamic specification changes in continuous annealing, which leads to finished products failing to meet temperature requirements and ultimately compromising product quality for downstream applications, this application provides a method and apparatus for controlling strip temperature during dynamic specification changes in continuous annealing. This method establishes a model of the relationship between furnace temperature and strip temperature by combining mechanistic models and empirical parameters. It pre-calculates the furnace temperature during the specification transition phase and the required control speed for the transition coil, achieving a smooth transition between furnace and strip temperatures. Compared to traditional closed-loop strip temperature control methods, which are affected by the accuracy of the strip thermometer, this method improves control accuracy and speed, enabling dynamic specification change transition control of strip temperature during continuous annealing.

[0022] The following examples illustrate this in detail.

[0023] To improve the accuracy of temperature control during the dynamic specification change stage of strip annealing while ensuring efficiency, this embodiment provides a method for controlling the temperature of strip during the dynamic specification change stage of strip annealing, where the executing entity is a temperature control device for the dynamic specification change stage. This temperature control device includes, but is not limited to, a server, such as... Figure 1 As shown, this method specifically includes the following: Step 100: Obtain the actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip steel speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip steel weld between the main coil strip steel and the secondary coil strip steel.

[0024] Specifically, if the estimated time from the strip weld to the furnace inlet is less than a preset time, the primary strip coil can be identified as the previous coil, and the secondary strip coil as the next coil. If the estimated time is greater than or equal to the preset time and the thicknesses of the previous and next coils are different, the strip with the higher preset priority can be identified as the primary coil, and the strip with the lower preset priority as the secondary coil. If the estimated time is greater than or equal to the preset time and the thicknesses of the previous and next coils are the same, the primary strip coil can be identified as the previous coil, and the secondary coil as the next coil. The preset priority can be set according to actual conditions, and this application does not limit it. For example, the preset priority can be strip thickness; the higher the strip thickness, the higher the priority.

[0025] Specifically, the "previous coil" of strip steel can refer to strip steel that is currently at least partially located inside the heating furnace, and the "next coil" of strip steel can refer to the coil following the "previous coil" of strip steel, located outside the heating furnace. Actual production parameter sets, historical batch samples, and their corresponding historical heating section radiation coefficients can be acquired periodically during the dynamic specification-changing stage of the strip steel continuous annealing process.

[0026] Specifically, the actual production parameters of the primary strip steel may include at least one of the following: actual plate temperature, thickness, mass, working area, specific heat capacity, corresponding comprehensive radiation coefficient, and protective gas correction coefficient. The actual production parameters of the secondary strip steel may include at least one of the following: actual plate temperature, thickness, mass, working area, specific heat capacity, corresponding comprehensive radiation coefficient, and protective gas correction coefficient. Actual furnace temperature, actual strip speed, and actual plate temperature can represent the current furnace temperature, current strip speed, and current plate temperature, respectively. Historical samples can be real production data obtained before step 100. Each historical sample may include at least one of the following: historical furnace temperature, historical strip temperature, thickness, mass, working area, specific heat capacity, strip speed, weld location, corresponding comprehensive radiation coefficient, and protective gas correction coefficient.

[0027] Step 200: Using batch historical samples, their respective historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coiled strip, obtain the corrected heating section radiation coefficient.

[0028] Step 300: Based on the corrected heating section radiation coefficient and the actual production parameter set, complete the plate temperature control of the main strip steel.

[0029] Specifically, the plate temperature control of the main coiled steel can be achieved based on the corrected heating section radiation coefficient, the actual production parameter set, and the preset original furnace temperature and plate temperature relationship model. The preset furnace temperature and plate temperature relationship model can be:

[0030] In the above formula, Q f This represents the energy exchanged due to radiative heat transfer, measured in kilocalories per hour. T g This represents the furnace temperature parameter, i.e., the average temperature of the heating furnace, in Kelvin (K). The heating furnace can be a furnace with heating elements. If the target velocity is to be calculated iteratively, then... T g The current actual furnace temperature is taken and not used as the adjustment amount for this iteration; if the iteration is to find the target furnace temperature, then... T g The initial value of the variable used for iterative adjustment can be the current actual furnace temperature, and the value after the iteration ends... T g As the target furnace temperature or furnace temperature setpoint; T b This indicates the average temperature of the strip, in Kelvin (K). T b This can be understood as the average temperature of the strip body at the current time step; it is recursively derived from the strip temperature of the previous time step in the iterative calculation, and corresponds to the temperature at the furnace outlet. T b It can be used as a predictor of strip steel temperature. F g This indicates the working area of ​​the strip steel, in meters. 2 ; dt represents the time step, which is dimensionless. If there are 1000 compensations per second, then dt = 0.001 / 3600. Q d This represents the energy exchanged due to heat convection, measured in kilocalories per hour. η This represents the protective gas correction factor, which is dimensionless and can be preset according to actual conditions. v The speed parameters are: strip speed in the heating section and wind speed of cooling gas in the cooling section, in m / s. C0 represents the equipment correction factor, which is a constant for a certain production environment and is dimensionless. When the heating furnace equipment remains unchanged, the equipment correction factor can be used as a preset calibration parameter and does not change frequently with the steel coil. This represents the corrected radiation coefficient of the heating section; t g , t b This indicates the average temperature of the strip steel in the heating furnace, in °C. C Specific heat capacity, unit: kcal / (kg·K); This represents the plate temperature after heating at the k-th time step, which is the plate temperature before heating at the (k+1)-th time step, in °C. This represents the plate temperature before heating at the k-th time step, in °C. This indicates the mass of the strip steel, in kg. Since the heating stage is primarily a radiation stage, only the radiation heat transfer coefficient is corrected. Because the convective heat transfer has little effect during the heating stage, the relevant parameters for corresponding heat transfer can be considered constant.

[0031] like Figure 2 As shown, in one embodiment, step 200 includes: Step 201: Using batch historical samples, the actual strip speed, and the strip thickness in the actual production parameters of the main coil strip, obtain the stability coefficient.

[0032] Specifically, the instability index of a historical sample can be determined using the actual strip speed, the strip thickness of the main coil, and each historical sample; the stability coefficient is then obtained based on the instability index of each historical sample. The instability index corresponding to the i-th historical sample can be determined using the following formula. :

[0033] In the formula, Let i be the time decay term for the i-th historical sample. The velocity difference gain coefficient for the i-th historical sample. For the actual strip speed, Let be the speed of the historical strip in the i-th historical sample. The normalized width of the velocity corresponding to the i-th historical sample. The thickness difference gain coefficient corresponding to the i-th historical sample. The thickness of the main coiled steel strip. Let be the strip thickness in the i-th historical sample. Let be the thickness normalized width of the i-th historical sample.

[0034] The time decay term indicates that the closer the corresponding actual production time is to the current time, the higher the reliability of the historical sample. The time decay term for each historical sample can be set according to the actual situation. For example, historical samples can be sorted from shortest to longest time based on the duration from their actual production time to the current time. The time decay term for the j-th historical sample is: max(1-α) (j-1),w min As a preferred option, the attenuation rate α = 0.5, w min =0.

[0035] The speed difference gain coefficient can represent historical samples with a higher degree of trust in the similarity between the strip speed and the actual strip speed. The speed difference gain coefficient for each historical sample can be set according to the actual situation. Preferably, the speed difference gain coefficient for the i-th historical sample... .

[0036] The thickness difference gain coefficient can represent historical samples with a higher degree of confidence in the similarity between the strip thickness and the actual strip thickness of the main coil. The thickness difference gain coefficient for each historical sample can be set according to actual conditions. Preferably, the thickness difference gain coefficient for the i-th historical sample... .

[0037] The velocity normalization width corresponding to the i-th historical sample It can represent the scale parameter or tolerance width for normalizing the speed difference, and is used to normalize the speed difference between the actual strip speed and the strip speed in the i-th historical sample.

[0038] The thickness normalized width corresponding to the i-th historical sample It can represent a scale parameter or tolerance width for normalizing the thickness difference, used to normalize the thickness difference between the thickness of the main coil and the thickness of the historical strip in the i-th historical sample.

[0039] The stability coefficient can be obtained from the following formula. :

[0040] In the formula, For the amplitude limiting mapping function, M This represents the number of historical samples. The stability coefficient can be used to characterize the effectiveness of online corrections.

[0041] Step 202: Obtain the historical reference radiation coefficient based on the historical heating segment radiation coefficient and sample weight corresponding to each historical sample.

[0042] Specifically, the historical reference radiation coefficient can be obtained according to the following formula. :

[0043] In the formula, Let be the sample weight of the i-th historical sample. Let be the historical heating segment radiation coefficient corresponding to the i-th historical sample. M This represents the number of historical samples. The sample weights of each historical sample can be set according to the actual situation, or the sample weights of historical samples can be constructed based on time similarity, speed similarity, and thickness similarity.

[0044] Furthermore, before step 202, the method may further include: determining the sample weight of the i-th historical sample according to the following formula. :

[0045] In the formula, , , Let each of the following represent the time, velocity, and thickness similarity terms of the i-th historical sample, respectively.

[0046] Specifically, similarity calculations can be performed on the actual production time corresponding to the i-th historical sample and the current time, with the result used as the time similarity term for the i-th historical sample; similarity calculations can be performed on the historical strip speed and the actual strip speed of the i-th historical sample, with the result used as the speed similarity term for the i-th historical sample; similarity calculations can be performed on the historical strip thickness and the strip thickness of the main coil of the i-th historical sample, with the result used as the thickness similarity term for the i-th historical sample. The time similarity term, speed similarity term, and thickness similarity term can be used to construct historical sample weights to improve the influence of recent historical samples that are closer to the current speed and thickness on the historical reference radiation coefficient.

[0047] Step 203: Obtain the corrected heating section radiation coefficient based on the stability coefficient, the historical reference radiation coefficient, and the preset first initial heating section radiation coefficient.

[0048] Specifically, the radiation coefficient correction amount can be obtained based on the stability coefficient, the historical reference radiation coefficient, and the preset first initial heating section radiation coefficient; the corrected heating section radiation coefficient can be obtained based on the radiation coefficient correction amount and the preset first initial heating section radiation coefficient.

[0049] (1) The correction amount for the radiation coefficient can be determined according to the following formula. :

[0050] In the formula, For stability coefficient, The preset first initial heating section radiation coefficient, This is the historical reference radiation coefficient.

[0051] The corrected radiation coefficient of the heating section can be determined using the following formula:

[0052] (2) Alternatively, depending on the situation, in the steady-state region or weld zone, the radiation coefficient correction can be determined according to the following formula. :

[0053] In the formula, For stability coefficient, The preset first initial heating section radiation coefficient, This is a historical reference radiation coefficient. The preset radiation coefficient of the first initial heating section can be set according to actual conditions, and this application does not impose any restrictions on it.

[0054] In the transition recovery region, the target number of samples required to achieve full correction can be introduced. Determine the correction amount for the radiation coefficient according to the following formula. :

[0055] In the formula, For stability coefficient, The preset first initial heating section radiation coefficient, Here, γ is the historical reference radiation coefficient, and γ is the asymptotic amplification factor during the transition recovery phase. M For historical sample size, The target number of samples required to achieve complete correction. and All settings can be customized according to actual circumstances; this application does not impose any restrictions on this. By introducing... It can be used to limit the number of historical samples to be used for correction in scenarios with a huge and infinite number of historical samples.

[0056] The corrected radiation coefficient of the heating section can be determined using the following formula:

[0057] In the formula, k= in the steady-state region or weld zone β In the transition recovery region k= γβ .

[0058] The corrected heating section emissivity can be the online corrected heating section emissivity. This correction method essentially smooths the offline baseline emissivity towards the online historical reference emissivity, thereby avoiding plate temperature fluctuations caused by sudden changes in the emissivity.

[0059] Furthermore, the historical samples can represent valid historical samples. A batch of original historical samples can be obtained, and based on a preset weld ignore interval, the original historical samples are filtered, with the filtered and retained original historical samples being the historical samples. The preset weld ignore interval is [p_min, p_max], and the speed switching boundary is [v_min, v_max]. If the weld position p in the original historical sample... i < p_min or p i If p_max is greater than the specified value, then the original historical sample is used as the historical sample; otherwise, the original historical sample is discarded. Alternatively, the original historical sample can be filtered based on the speed switching boundary. When a speed switching boundary is detected in a recent historical sample, residual samples crossing the speed switching boundary are further discarded to eliminate the interference of old operating condition thermal inertia on the current correction result.

[0060] Furthermore, after completing the temperature control of the main coiled steel, a new original historical sample can be obtained based on the actual furnace temperature, actual strip speed, and actual production parameters of the main coiled steel, which will facilitate the next execution of step 100.

[0061] In one embodiment, the strip temperature control method during the dynamic specification change stage of the strip annealing process further includes: Step 001: Based on the preset original furnace temperature and plate temperature relationship model, the length of the heating furnace, and the historical samples, determine the radiation coefficient of the historical heating section corresponding to the historical samples.

[0062] Specifically, the historical samples can be input into the preset original furnace temperature and plate temperature relationship model. The heating section radiation coefficient in the preset original furnace temperature and plate temperature relationship model is adjusted until the predicted strip temperature at the furnace outlet output by the preset original furnace temperature and plate temperature relationship model reaches the preset plate temperature requirement. The current heating section radiation coefficient in the preset original furnace temperature and plate temperature relationship model is then determined as the historical heating section radiation coefficient corresponding to the historical samples. The preset original furnace temperature and plate temperature relationship model can be:

[0063] In the above formula, This represents the energy exchanged due to radiative heat transfer for the i-th historical sample, in kcal / h. This represents the historical furnace temperature in the i-th historical sample, which can be the average temperature of the furnace with heating, in K; This represents the average temperature of the strip corresponding to the i-th historical sample, in K. This represents the working area of ​​the historical strip steel in the i-th historical sample, in meters. 2 ; dt dt represents the time step, which is dimensionless. If there are 1000 compensations per second, then dt = 0.001 / 3600. This represents the energy exchanged due to thermal convection for the i-th historical sample, in kcal / h. represents the protective gas correction coefficient in the i-th historical sample, which is dimensionless; Represents the velocity of the historical strip in the i-th historical sample, in m / s; This represents the equipment correction factor, which is a constant for a specific production environment and is dimensionless. This represents the radiation coefficient of the heating section in the preset model of the relationship between the original furnace temperature and the plate temperature. This represents the historical furnace temperature in the i-th historical sample, which can be the average temperature of the furnace with heating, in °C. This represents the average temperature of the strip corresponding to the i-th historical sample, in °C. Represents the specific heat capacity of the i-th historical sample, in kcal / (kg·K); This represents the plate temperature after heating at the k-th time step corresponding to the i-th historical sample, which is the plate temperature before heating at the (k+1)-th time step, in °C. This represents the plate temperature before heating at the k-th time step corresponding to the i-th historical sample, in °C. This represents the mass of the historical strip steel in the i-th historical sample, in kg.

[0064] like Figure 3 As shown, in one embodiment, step 001 includes: Step 011: Use the preset second initial historical heating section radiation coefficient as the heating section radiation coefficient in the preset original furnace temperature and plate temperature relationship model.

[0065] Step 012: Execute the first iteration step, which includes: obtaining the historical predicted strip temperature at the furnace outlet corresponding to the historical sample based on the preset original furnace temperature and plate temperature relationship model, the furnace length and the historical sample.

[0066] Step 013: Determine whether the predicted plate temperature of the historical strip steel has reached the preset plate temperature requirement. If yes, proceed to step 014; otherwise, proceed to step 015.

[0067] Step 014: Determine the radiation coefficient of the heating section in the current preset original furnace temperature and plate temperature relationship model as the historical heating section radiation coefficient corresponding to the historical sample.

[0068] Step 015: Adjust the radiation coefficient of the heating section in the preset original furnace temperature and plate temperature relationship model, and execute step 012 again.

[0069] Specifically, the preset second initial heating section radiation coefficient can be set according to actual conditions, and the application does not impose any restrictions on this. The preset first initial heating section radiation coefficient and the preset second initial heating section radiation coefficient can be the same or different.

[0070] Specifically, the preset plate temperature requirement can be set according to actual conditions, and this application does not impose any restrictions on it. The preset plate temperature requirement may refer to the required plate temperature at the furnace outlet corresponding to the historical sample. Different historical samples may have different preset plate temperature requirements.

[0071] In one embodiment, each of the historical samples includes: historical strip temperature and historical production parameters, which include: historical furnace temperature, historical strip quality, working area, speed, corresponding comprehensive radiation coefficient and protective gas correction coefficient; like Figure 4 As shown, correspondingly, step 012, which involves obtaining the predicted strip temperature at the furnace outlet corresponding to the historical sample based on the preset original furnace temperature and strip temperature relationship model, the furnace length, and the historical sample, includes: Step 0121: Determine the number of heating process steps based on the length of the heating furnace and the speed of the historical strip steel.

[0072] Specifically, the number of steps in the heating process can be: heating furnace length / (historical strip speed × 1000).

[0073] Step 0122: Use the historical strip temperature as the strip temperature before heating in the current time step.

[0074] Step 0123: Execute the second iteration step, which includes: inputting the historical production parameters and the strip temperature before heating in the current time step into the preset original furnace temperature and plate temperature relationship model to obtain the strip temperature before heating in the next time step.

[0075] Step 0124: Determine whether the number of times the second iteration step has been executed has reached the number of heating process steps. If yes, proceed to step 0125; otherwise, proceed to step 0126.

[0076] Step 0125: Determine the strip temperature before heating in the next time step as the historical strip predicted plate temperature.

[0077] Step 0126: Use the strip temperature before heating in the next time step as the strip temperature before heating in the current time step, and execute step 0123 again.

[0078] For example, assuming the heating process has 2000 steps, and the plate temperature requirement corresponding to the i-th historical sample is the target outlet plate temperature T0 corresponding to the historical sample, the first iteration step includes: The first execution of the second iteration step: The plate temperature of the historical strip in the i-th historical sample is taken as the plate temperature before heating in the first time step. ,Will The historical production parameters in the i-th historical sample are used to input the radiation coefficient of the heating section, which is the preset second initial radiation coefficient of the heating section. Based on the preset original furnace temperature and plate temperature relationship model, the plate temperature of the i-th historical sample after heating in the first time step is obtained. , This can be equivalent to the plate temperature of the i-th historical sample before heating in the second time step. .

[0079] The second iteration step is executed: The historical production parameters in the i-th historical sample are used to input the radiation coefficient of the heating section, which is the preset second initial radiation coefficient of the heating section. The preset model of the relationship between the original furnace temperature and the plate temperature can be used to obtain the plate temperature of the i-th historical sample after heating in the second time step. , This can be equivalent to the plate temperature of the i-th historical sample before heating in the third time step. ...

[0080] By analogy, when the first iteration step is executed for the first time, the plate temperature of the i-th historical sample after heating at the 2000th time step can be obtained as the historical strip steel predicted plate temperature T1 at the furnace outlet corresponding to the i-th historical sample.

[0081] If T1 does not reach T0, then the radiation coefficient of the heating section in the preset original furnace temperature and plate temperature relationship model can be randomly adjusted to... .

[0082] The second execution of the first iteration steps includes: First execution of the second iteration step: The historical production parameters input heating section radiation coefficient in the i-th historical sample are: The preset original furnace temperature and plate temperature relationship model is used to obtain the plate temperature of the i-th historical sample after heating in the first time step, that is, the plate temperature of the i-th historical sample before heating in the second time step.

[0083] The second iteration step is executed: the historical production parameters from the i-th historical sample and its plate temperature before heating in the second time step are input into the heating section's radiation coefficient. The preset model of the relationship between the original furnace temperature and the plate temperature can be used to obtain the plate temperature of the i-th historical sample after heating in the second time step, that is, the plate temperature of the i-th historical sample before heating in the third time step...

[0084] By analogy, the plate temperature of the i-th historical sample after heating at the 2000th time step can be obtained when the first iteration step is executed for the second time. This plate temperature is then used as the predicted plate temperature T2 of the historical strip at the furnace outlet corresponding to the i-th historical sample.

[0085] If T2 reaches T0, then the radiation coefficient of the historical heating segment corresponding to the i-th historical sample can be determined as follows: .

[0086] like Figure 5 As shown, in one embodiment, step 300 includes: Step 301: Based on the actual strip speed and the position of the strip weld, determine whether the estimated time from the strip weld to the furnace inlet is less than the preset time. If so, determine that the main strip coil is the previous strip coil and the secondary strip coil is the next strip coil. Based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main strip coil, and the corrected heating section radiation coefficient, obtain the target strip speed. Adjust the actual strip speed to the target strip speed to complete the temperature control of the main strip coil.

[0087] Specifically, the estimated time from the strip weld to the furnace inlet can be: the distance between the strip weld and the furnace inlet / the actual strip speed. The preset time can be set according to actual conditions, and this application does not impose any restrictions on it. The target strip speed can be sent to the strip production system, which can then adjust the actual strip speed to the target strip speed.

[0088] Step 302: If the estimated time taken is greater than or equal to the preset time and the strip thickness of the previous and subsequent coils is different, then the strip with the higher preset priority among the previous and subsequent coils is determined as the primary coil, and the strip with the lower preset priority is determined as the secondary coil. Based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the primary coil, and the corrected heating section radiation coefficient, the target furnace temperature is obtained, and the actual furnace temperature is adjusted to the target furnace temperature to complete the plate temperature control of the primary coil.

[0089] Specifically, the target furnace temperature can be sent to the strip steel production system, and the actual furnace temperature can be adjusted to the target furnace temperature through the strip steel production system.

[0090] Step 303: If the estimated time is greater than or equal to the preset time and the strip thickness of the previous and next coils is the same, then the primary coil is determined to be the previous coil and the secondary coil to be the next coil. Based on the preset process settings, the furnace length, the actual furnace temperature, the actual strip speed, the actual production parameters of the primary coil, and the corrected heating section radiation coefficient, the target furnace temperature is obtained. The actual furnace temperature is then adjusted to the target furnace temperature to complete the temperature control of the primary coil.

[0091] Specifically, the target furnace temperature can be sent to the strip steel production system, and the actual furnace temperature can be adjusted to the target furnace temperature through the strip steel production system.

[0092] In one embodiment, step 301, which involves obtaining the target strip speed based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main coil strip, and the corrected heating section radiation coefficient, includes: Step 3011: Using the actual strip speed as the speed parameter, execute the third iteration step, which includes: predicting the predicted strip temperature at the outlet of the heating furnace based on the heating furnace length, actual furnace temperature, speed parameter, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model.

[0093] Specifically, the time step W can be: furnace length / (actual strip speed × 1000). The strip temperature obtained at the Wth time step after heating during any third iteration can be used as the predicted strip temperature at the furnace outlet obtained in this third iteration.

[0094] Step 3012: Determine whether the predicted strip temperature has reached the preset strip temperature requirement. If so, determine the current speed parameter as the target strip speed; otherwise, adjust the speed parameter and execute the third iteration step again.

[0095] Specifically, the preset plate temperature requirement can be the plate temperature requirement of the main coiled strip steel. The mass of the main coiled strip steel can be taken as the mass G of the strip steel, and the working area of ​​the main coiled strip steel can be taken as the working area of ​​the strip steel. F g The comprehensive radiation coefficient corresponding to the main coiled steel is used as the comprehensive radiation coefficient C of the strip steel and the heating furnace. L The protective gas correction factor for the main coiled steel is used as the protective gas correction factor. η The actual furnace temperature is used as the furnace temperature parameter. T g The actual strip speed is used as a speed parameter. v The actual temperature of the main strip steel is used as the temperature of the strip before heating in the first time step. Input the preset furnace temperature and plate temperature relationship model, and adjust the speed parameter in the preset furnace temperature and plate temperature relationship model. v The process continues until the predicted strip temperature at the furnace outlet, output by the preset furnace temperature and plate temperature relationship model, reaches the preset plate temperature requirement. Then, the speed parameter in the current preset furnace temperature and plate temperature relationship model is determined as the target strip speed. The equipment correction coefficient in the preset furnace temperature and plate temperature relationship model can correct the impact of furnace installation / manufacturing deviations on heat exchange. It can be preset according to actual conditions, and this application does not impose any restrictions on it.

[0096] In one embodiment, step 302, which involves obtaining the target furnace temperature based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main coil strip, and the corrected heating section radiation coefficient, includes: Step 3021: Using the actual furnace temperature as the furnace temperature parameter, execute the fourth iteration step, which includes: predicting the predicted strip temperature at the furnace outlet based on the furnace length, actual furnace temperature, furnace temperature parameter, actual strip speed, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model.

[0097] Specifically, the time step W can be: furnace length / (actual strip speed × 1000). The strip temperature obtained at the Wth time step after heating during any execution of the fourth iteration can be used as the predicted strip temperature at the furnace outlet obtained during this execution of the fourth iteration.

[0098] Step 3022: Determine whether the predicted strip temperature has reached the preset temperature requirement. If so, determine the current furnace temperature parameter as the target furnace temperature; otherwise, adjust the furnace temperature parameter and execute the fourth iteration step again.

[0099] Specifically, the mass of the main coiled strip can be taken as the mass G of the strip, and the working area of ​​the main coiled strip can be taken as the working area of ​​the strip. F g The comprehensive radiation coefficient corresponding to the main coiled steel is used as the comprehensive radiation coefficient C of the strip steel and the heating furnace. L The protective gas correction factor for the main coiled steel is used as the protective gas correction factor. η The actual furnace temperature is used as the furnace temperature parameter. T g The initial value, the actual strip speed is used as the speed parameter. v The actual temperature of the main strip steel is used as the temperature of the strip before heating in the first time step. Input the preset furnace temperature and plate temperature relationship model, and adjust the furnace temperature parameters in the preset furnace temperature and plate temperature relationship model. T g (i.e., adjusting during iteration) T g Until the predicted strip temperature at the furnace outlet output by the preset furnace temperature and plate temperature relationship model reaches the preset plate temperature requirement, the furnace temperature parameter in the current preset furnace temperature and plate temperature relationship model is determined as the target furnace temperature.

[0100] In one embodiment, step 303, which involves obtaining the target furnace temperature based on preset process settings, the furnace length, the actual furnace temperature, the actual strip speed, the actual production parameters of the main coil strip, and the corrected heating section radiation coefficient, includes: Step 3031: The ratio of the preset process setting value to the strip thickness is determined as the set strip speed.

[0101] Specifically, the preset process setting value, i.e., TV value, can be: Thick (strip thickness × set strip speed).

[0102] Step 3032: Using the actual furnace temperature as the furnace temperature parameter, execute the fifth iteration step, which includes: predicting the predicted strip temperature at the furnace outlet based on the furnace length, actual furnace temperature, furnace temperature parameter, set strip speed, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model.

[0103] Specifically, the time step W can be: furnace length / (set strip speed × 1000). The strip temperature obtained at the Wth time step after heating during any execution of the fifth iteration can be used as the predicted strip temperature at the furnace outlet obtained during this execution of the fifth iteration.

[0104] Step 3033: Determine whether the predicted strip temperature has reached the preset temperature requirement. If so, the current furnace temperature parameter is determined as the target furnace temperature. Otherwise, adjust the furnace temperature parameter and execute the fifth iteration step again.

[0105] Specifically, if the set strip speed is different from the actual strip speed, then the mass of the previous coil of strip can be taken as the mass G of the strip, and the working area of ​​the previous coil of strip can be taken as the working area of ​​the strip. F g The comprehensive radiation coefficient corresponding to the previous coil of strip steel is taken as the comprehensive radiation coefficient C of the strip steel and the heating furnace. L The protective gas correction factor corresponding to the previous coil of strip is used as the protective gas correction factor. η The actual furnace temperature is used as the furnace temperature parameter. T g The initial value, wherein the set strip speed is used as the speed parameter. v The actual temperature of the previous coil of strip is used as the temperature of the strip before heating in the first time step. Input the preset furnace temperature and plate temperature relationship model, and adjust the furnace temperature parameters in the preset furnace temperature and plate temperature relationship model. T g Until the predicted strip temperature at the furnace outlet output by the preset furnace temperature and plate temperature relationship model reaches the preset plate temperature requirement, the furnace temperature parameter in the current preset furnace temperature and plate temperature relationship model is determined as the target furnace temperature.

[0106] To facilitate understanding of this solution, this application provides an application example of a plate temperature control method during the dynamic specification change stage of strip steel continuous annealing, which can control the plate temperature during the annealing process. The method includes: Step 1: Establish a mathematical model, which is the process relationship formula for strip steel (including its physical properties, width, and thickness) reaching a certain temperature through heating in a furnace (furnace temperature and production speed). This can be equivalent to the preset furnace temperature and plate temperature relationship model mentioned above. Then, several solution and adjustment modules can be established, and finally, the temperature control of the strip steel can be achieved through the control process in Step 3.

[0107] The heating and cooling stages of the furnace both include radiative heat transfer and convective heat transfer processes. A pre-defined model relating furnace temperature and plate temperature may include: For radiative heat exchange processes:

[0108] In the above formula, Q f This represents the energy exchanged due to radiative heat transfer, measured in kilocalories per hour. This represents the corrected radiation coefficient of the heating section; T g , T b This indicates the average temperature of the strip steel in the heating furnace, in Kelvin (K). F g This indicates the working area of ​​the strip steel, in meters. 2 ; dt represents the time step, which is dimensionless. If there are 1000 compensations per second, then dt = 0.001 / 3600.

[0109] For convective heat transfer processes:

[0110] In the above formula, Q d This represents the energy exchanged due to heat convection, measured in kilocalories per hour. η This represents the protective gas correction factor, which is dimensionless. v The speed is indicated by the strip speed in the heating section and the wind speed of the cooling gas in the cooling section, in m / s. C 0 represents the equipment correction factor, which is a constant for a specific production environment and is dimensionless. t g , t b This indicates the average temperature of the strip steel in the heating furnace, in °C. F g This indicates the working area of ​​the strip steel, in meters. 2 .

[0111] Based on the heat transfer principles of the steel industry furnace design manual, the above formula was determined. Simultaneously, the corresponding equipment correction factor C0 and radiation factor C were determined using actual production data from the field. L The formulas for determining the heating furnace temperature and strip temperature are then established. Using thermodynamic theorems, the following formulas are determined:

[0112] In the above formula, Q f This represents the energy exchanged due to radiative heat transfer, measured in kilocalories per hour. Q d This represents the energy exchanged due to heat convection, measured in kilocalories per hour. C Specific heat capacity, unit: kcal / (kg·K); This represents the plate temperature after heating at the k-th time step, which is the plate temperature before heating at the (k+1)-th time step, in °C. This represents the plate temperature before heating at the k-th time step, in °C. This indicates the mass of the strip steel, in kg.

[0113] Step 2: Correct the radiation coefficient of the heating section.

[0114] The radiation coefficient of the heating section foundation calculated by the offline model is updated online. The current weld position p, strip thickness h, strip speed v, and the radiation coefficient of the main coil foundation are acquired in real time. 0 (i.e., the radiation coefficient of the first initial heating section preset above), can be deduced from the furnace temperature and plate temperature. 0, and read the most recent multiple original historical samples Di=(p_i,h_i,v_i, _i), where, _i represents the radiation coefficient of the historical heating section corresponding to the historical operating conditions.

[0115] To avoid the influence of the weld disturbance zone on the correction result, a weld ignoring interval [p_min, p_max] is set first, and only the original historical samples satisfying p_i<p_min or p_i>p_max are retained; when it is detected that there is a speed switching boundary in the recent original historical samples, the residual samples across the speed switching boundary are further eliminated to eliminate the interference of the thermal inertia of the old working condition on the current correction result, and the finally retained original historical samples are taken as the aforementioned historical samples (i.e., valid historical samples).

[0116] For the valid samples, the instability indicator can be constructed as follows:

[0117] Further, the stability coefficient is obtained:

[0118] In the formula, is the time decay term of the i-th historical sample, is the speed difference gain coefficient of the i-th historical sample, is the actual strip speed, is the historical strip speed in the i-th historical sample, is the speed normalization width corresponding to the i-th historical sample, is the thickness difference gain coefficient corresponding to the i-th historical sample, is the strip thickness of the main coil strip, is the strip thickness in the i-th historical sample, is the thickness normalization width of the i-th historical sample; is the amplitude limiting mapping function, M is the number of historical samples. β is used to characterize the effective strength of online correction.

[0119] The historical sample weight is constructed according to time similarity, speed similarity and thickness similarity, and the historical reference radiation coefficient is obtained:

[0120] In the formula, , , sequentially represent the time, speed and thickness similarity terms of the i-th historical sample, represents the historical reference radiation coefficient obtained by weighting the recent similar working condition samples.

[0121] The radiation coefficient correction amount can be expressed as:

[0122] In the formula, γ is the asymptotic amplification factor during the transition recovery phase. M n is the number of historical samples, and n_0 is the target number of samples required to achieve complete correction.

[0123] Therefore, the radiation coefficient of the heating section after online correction is:

[0124] Specifically, k=β in the steady-state region or weld zone, and k=γβ in the transition recovery region. This correction method essentially smooths the offline baseline emissivity towards the online historical reference emissivity, thereby avoiding board temperature fluctuations caused by abrupt changes in the emissivity.

[0125] The corrected radiation coefficient was then substituted back into the preset furnace temperature and plate temperature relationship model.

[0126] Step 3: Combine with the iterative module to execute the control flow. The control flow loop time can be once every 2 seconds. The control system will recalculate and issue control parameters every 2 seconds, including furnace temperature, speed, and plate temperature. Step 3 includes: Step 3.1: Determine if the time from the weld seam of the steel coil to the furnace inlet is less than 5 seconds. If so, use the transfer module—speed determination module—to determine whether the next coil of steel entering the furnace can reach the target plate temperature under the current speed and furnace temperature conditions. If speed adjustment is needed, calculate the corresponding speed setpoint in advance (which can be equivalent to the aforementioned target strip steel speed) and send it to the control system (also known as the strip steel production system). If the determination time is greater than or equal to 5 seconds, proceed to step 3.2. The target plate temperature can be equivalent to the aforementioned preset plate temperature requirement.

[0127] Step 3.2: Determine if a heating range exists for the transition steel coil, i.e., determine if furnace temperature adjustment is necessary. Considering the special characteristics of the TV value enhancement module and the heating of the transition steel coil, heating of the transition steel coil is prioritized. The system assesses the current speed and furnace temperature conditions, as well as the target plate temperature of the previous and subsequent steel coils. Then, based on the strategy of prioritizing the thicker coils (generally, thicker coils are prioritized, and the furnace temperature conditions corresponding to the priority steel coils meeting the target plate temperature are used to determine if a heating range exists).

[0128] Step 3.3: TV value module determination. Since each steel coil has a set TV value, it is necessary to determine whether the current production speed has reached the speed specified by the TV value (i.e., the set strip speed mentioned above). If it has not reached the set speed, the TV value adjustment module 1.2.4 is needed to calculate the required furnace temperature conditions based on the set strip speed and send them to the control system.

[0129] The iterative module may include: Module 1.2.1 for calculating plate temperature given furnace temperature: Based on the preset furnace temperature and plate temperature relationship model, the entire control process is divided into 1000 time steps per second. For each time step, the inlet temperature (i.e., the plate temperature before heating in that time step) and the outlet temperature (i.e., the plate temperature after heating in that time step) are calculated through the preset furnace temperature and plate temperature relationship model. Finally, the corresponding plate temperature is calculated based on the set furnace temperature.

[0130] Module 1.2.2 for calculating furnace temperature from known plate temperature: Given an initial furnace temperature (an empirical value), the plate temperature is calculated using the known furnace temperature conditions through the plate temperature calculation module 1.2.1. Then, based on the calculated plate temperature and the target plate temperature, the furnace temperature is corrected until the plate temperature obtained under a certain furnace temperature condition is consistent with the target plate temperature, at which point the iteration ends.

[0131] Speed ​​adjustment module 1.2.3 (Given plate temperature and furnace temperature, calculate strip running speed): Given the plate temperature and furnace temperature, by providing an initial speed and calculating the plate temperature and target plate temperature, the speed can be adjusted accordingly. v The process continues until the board temperature obtained at a certain furnace temperature is consistent with the target board temperature, at which point the iteration ends.

[0132] TV value adjustment module 1.2.4: If the plate temperature and furnace temperature are known, and the speed needs to be increased, the TV value = Thick (strip thickness × target strip speed). This can be determined through the speed adjustment module 1.2.3, which calculates the required speed. v The value refers to the required furnace temperature.

[0133] Transition Module -- Speed ​​Determination Module 1.2.5: Under the current speed and furnace temperature conditions, determine whether the next coil of steel entering the heating furnace can reach the target temperature. If the speed needs to be adjusted, the speed setting value can be calculated in advance through the speed adjustment module 1.2.3.

[0134] Transition Module -- Furnace Temperature Regulation Module 1.2.6: Determine the speed and furnace temperature conditions T under the current circumstances. B Considering that the previous and subsequent coils of steel reach their target temperatures respectively, the furnace temperature condition T is determined based on the principle of prioritizing the thicker coils (generally, thicker coils are given priority). N This determines whether a heating range exists; the heating range is T. N -T B This is on the premise that the difference is positive, i.e., only the temperature increases.

[0135] In a specific application example, such as Figure 6 As shown, the control process includes: coefficient correction, determining whether the weld position is within 5 seconds, if so, then through the transition module - speed determination module 1.2.5, determining whether the target strip speed or speed set value needs to be calculated based on the transition steel coil, if not, then determining whether the heating range exists, if so, then using the transition module - furnace temperature adjustment module 1.2.6, calculating the target furnace temperature or furnace temperature set value, if not, then determining whether the TV value meets the requirements, if so, then using the TV value adjustment module 1.2.4 to increase the TV value, if no requirements are met, then the control parameters are issued and the control ends.

[0136] From a software perspective, in order to improve the accuracy of temperature control during the dynamic specification change stage of strip annealing while ensuring efficiency, this application provides an embodiment of a strip temperature control device for the dynamic specification change stage of strip annealing, which implements all or part of the aforementioned strip temperature control method. See [link to embodiment]. Figure 7 The temperature control device for the dynamic specification change stage during the continuous annealing of strip steel specifically includes the following components: The acquisition module 01 is used to acquire the actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip weld between the main coil strip steel and the secondary coil strip steel. Correction module 02 is used to obtain the corrected heating section radiation coefficient by using batch historical samples, their respective historical heating section radiation coefficients, the actual strip speed and the actual production parameters of the main coil strip. Control module 03 is used to control the plate temperature of the main strip steel according to the corrected heating section radiation coefficient and the actual production parameter set.

[0137] The embodiment of the plate temperature control device for the dynamic specification change stage during the continuous strip annealing process provided in this specification can be used to execute the processing flow of the embodiment of the plate temperature control method for the dynamic specification change stage during the continuous strip annealing process described above. Its function will not be repeated here, but can be referred to the detailed description of the embodiment of the plate temperature control method for the dynamic specification change stage during the continuous strip annealing process described above.

[0138] Figure 8 This is a schematic diagram of the physical structure of an electronic device provided in an embodiment of the present invention, such as... Figure 8As shown, the electronic device includes: a memory 801, a processor 802, and a computer program stored in the memory 801 and executable on the processor 802. When the processor 802 executes the computer program, it implements the following method: The actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients are obtained during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip weld between the main coil strip steel and the secondary coil strip steel. The corrected heating section radiation coefficient is obtained by using a batch of historical samples, their respective historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coil strip. Based on the corrected heating section radiation coefficient and the actual production parameter set, the plate temperature control of the main strip steel is completed.

[0139] This embodiment discloses a computer program product, which includes a computer program that, when executed by a processor, implements the following method: The actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients are obtained during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip weld between the main coil strip steel and the secondary coil strip steel. The corrected heating section radiation coefficient is obtained by using a batch of historical samples, their respective historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coil strip. Based on the corrected heating section radiation coefficient and the actual production parameter set, the plate temperature control of the main strip steel is completed.

[0140] This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the following method: The actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients are obtained during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip weld between the main coil strip steel and the secondary coil strip steel. The corrected heating section radiation coefficient is obtained by using a batch of historical samples, their respective historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coil strip. Based on the corrected heating section radiation coefficient and the actual production parameter set, the plate temperature control of the main strip steel is completed.

[0141] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0142] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0143] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0144] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0145] In the description of this specification, the references to terms such as "an embodiment," "a specific embodiment," "some embodiments," "for example," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0146] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for controlling the temperature of strip steel during the dynamic specification-changing stage of continuous annealing, characterized in that, include: The actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients are obtained during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip weld between the main coil strip steel and the secondary coil strip steel. The corrected heating section radiation coefficient is obtained by using a batch of historical samples, their respective historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coil strip. Based on the corrected heating section radiation coefficient and the actual production parameter set, the plate temperature control of the main strip steel is completed.

2. The method for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing according to claim 1, characterized in that, The process of obtaining the corrected heating section radiation coefficient using batch historical samples, their respective corresponding historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coiled strip includes: The stability coefficient is obtained by using a batch of historical samples, the actual strip speed, and the strip thickness in the actual production parameters of the main coil strip. The historical reference radiation coefficient is obtained based on the historical heating segment radiation coefficient and sample weight corresponding to each historical sample. The corrected heating section radiation coefficient is obtained based on the stability coefficient, the historical reference radiation coefficient, and the preset first initial heating section radiation coefficient.

3. The method for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing according to claim 1 or 2, characterized in that, Also includes: Based on the preset original furnace temperature and plate temperature relationship model, the length of the heating furnace, and the historical samples, the radiation coefficient of the historical heating section corresponding to the historical samples is determined.

4. The method for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing according to claim 3, characterized in that, The step of determining the historical heating section radiation coefficient corresponding to the historical sample based on the preset original furnace temperature and plate temperature relationship model, the furnace length, and the historical sample includes: The preset second initial historical heating section radiation coefficient is used as the heating section radiation coefficient in the preset original furnace temperature and plate temperature relationship model. The first iteration step is executed, which includes: obtaining the historical strip steel predicted plate temperature at the furnace outlet corresponding to the historical sample based on the preset original furnace temperature and plate temperature relationship model, the furnace length and the historical sample. Determine whether the predicted plate temperature of the historical strip steel meets the preset plate temperature requirement. If so, determine the heating section radiation coefficient in the current preset original furnace temperature and plate temperature relationship model as the historical heating section radiation coefficient corresponding to the historical sample. Otherwise, adjust the heating section radiation coefficient in the preset original furnace temperature and plate temperature relationship model and execute the first iteration step again.

5. The method for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing according to claim 4, characterized in that, Each of the historical samples includes: historical strip temperature and historical production parameters, which include: historical furnace temperature, historical strip quality, working area, speed, corresponding comprehensive radiation coefficient and protective gas correction coefficient; Correspondingly, the step of obtaining the historical predicted strip temperature at the furnace outlet corresponding to the historical sample based on the preset original furnace temperature and strip temperature relationship model, the furnace length, and the historical sample includes: The number of heating process steps is determined based on the length of the heating furnace and the speed of the historical strip steel. The historical strip temperature is used as the strip temperature before heating in the current time step. The second iteration step includes: inputting the historical production parameters and the strip temperature before heating in the current time step into the preset original furnace temperature and plate temperature relationship model to obtain the strip temperature before heating in the next time step. Determine whether the number of times the second iteration step has been executed has reached the number of heating process steps. If so, determine the strip temperature before heating in the next time step as the historical predicted strip temperature. Otherwise, take the strip temperature before heating in the next time step as the strip temperature before heating in the current time step and execute the second iteration step again.

6. The method for controlling the plate temperature during the dynamic specification change stage of strip annealing according to claim 1, characterized in that, The step of controlling the plate temperature of the main strip steel based on the corrected heating section radiation coefficient and the actual production parameter set includes: Based on the actual strip speed and the position of the strip weld, it is determined whether the estimated time from the strip weld to the furnace inlet is less than the preset time. If so, the main strip coil is determined to be the previous strip coil, and the secondary strip coil is determined to be the next strip coil. Based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main strip coil, and the corrected heating section radiation coefficient, the target strip speed is obtained. The actual strip speed is adjusted to the target strip speed to complete the plate temperature control of the main strip coil. If the estimated time taken is greater than or equal to the preset time and the strip thickness of the previous and subsequent coils is different, then the strip with the higher preset priority among the previous and subsequent coils is determined as the primary coil, and the strip with the lower preset priority is determined as the secondary coil. Based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the primary coil, and the corrected heating section radiation coefficient, the target furnace temperature is obtained, and the actual furnace temperature is adjusted to the target furnace temperature to complete the plate temperature control of the primary coil. If the estimated time taken is greater than or equal to the preset time and the strip thickness of the previous and subsequent coils is the same, then the primary coil is determined to be the previous coil and the secondary coil to be the subsequent coil. Based on the preset process settings, the furnace length, the actual furnace temperature, the actual strip speed, the actual production parameters of the primary coil, and the corrected heating section radiation coefficient, the target furnace temperature is obtained, and the actual furnace temperature is adjusted to the target furnace temperature to complete the plate temperature control of the primary coil.

7. The method for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing according to claim 6, characterized in that, The process of obtaining the target strip speed based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main coil strip, and the corrected heating section radiation coefficient includes: Using the actual strip speed as a speed parameter, the third iteration step is executed. The third iteration step includes: predicting the predicted strip temperature at the outlet of the heating furnace based on the heating furnace length, actual furnace temperature, speed parameter, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model. Determine whether the predicted strip temperature has reached the preset strip temperature requirement. If so, determine the current speed parameter as the target strip speed; otherwise, adjust the speed parameter and execute the third iteration step again.

8. The method for controlling the plate temperature during the dynamic specification change stage of strip annealing according to claim 6, characterized in that, The process of obtaining the target furnace temperature based on the furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main coiled strip, and the corrected heating section radiation coefficient includes: Using the actual furnace temperature as the furnace temperature parameter, the fourth iteration step is executed. The fourth iteration step includes: predicting the predicted strip temperature at the furnace outlet based on the furnace length, actual furnace temperature, furnace temperature parameter, actual strip speed, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model. Determine whether the predicted strip temperature has reached the preset temperature requirement. If so, set the current furnace temperature parameter as the target furnace temperature; otherwise, adjust the furnace temperature parameter and execute the fourth iteration step again.

9. The method for controlling the plate temperature during the dynamic specification change stage of strip steel continuous annealing according to claim 6, characterized in that, The process of obtaining the target furnace temperature based on preset process settings, furnace length, actual furnace temperature, actual strip speed, actual production parameters of the main coil strip, and the corrected heating section radiation coefficient includes: The ratio of the preset process setting value to the strip thickness is determined as the set strip speed; Using the actual furnace temperature as the furnace temperature parameter, the fifth iteration step is executed. The fifth iteration step includes: predicting the predicted strip temperature at the furnace outlet based on the furnace length, actual furnace temperature, furnace temperature parameter, set strip speed, actual production parameters of the main coil strip, the corrected heating section radiation coefficient, and the preset furnace temperature and plate temperature relationship model. Determine whether the predicted strip temperature has reached the preset temperature requirement. If so, the current furnace temperature parameter is determined as the target furnace temperature; otherwise, adjust the furnace temperature parameter and execute the fifth iteration step again.

10. A strip temperature control device for the dynamic specification-changing stage during continuous strip annealing, characterized in that, include: The acquisition module is used to acquire the actual production parameter set, batch historical samples and their corresponding historical heating section radiation coefficients during the dynamic specification change stage of strip steel continuous annealing. The actual production parameter set includes: heating furnace length, actual furnace temperature, actual strip speed, actual production parameters of main coil strip steel, actual production parameters of secondary coil strip steel, and the position of the strip weld between the main coil strip steel and the secondary coil strip steel. The correction module is used to obtain the corrected heating section radiation coefficient by utilizing a batch of historical samples, their respective historical heating section radiation coefficients, the actual strip speed, and the actual production parameters of the main coil strip. The control module is used to control the plate temperature of the main strip steel according to the corrected heating section radiation coefficient and the actual production parameter set.

11. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the plate temperature control method for the dynamic specification change stage during the continuous annealing of strip steel as described in any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the plate temperature control method for the dynamic specification change stage during the continuous annealing of strip steel as described in any one of claims 1 to 9.

13. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the plate temperature control method for the dynamic specification change stage during the continuous annealing of strip steel as described in any one of claims 1 to 9.

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