A collaborative control method for dry and wet films based on a full-detection area density scanner

Abstract

The present invention relates to the technical field of dry and wet film coordinated control, and specifically to a dry and wet film coordinated control method based on a full-detection surface density scanner. The method of the present invention uses a full-detection surface density scanner for detection at both the dry film detection point and the wet film detection point, and matches the dry film surface density and the wet film original surface density to perform online fitting, establish a dry and wet film parameter mapping model, and perform a cyclic verification on the fitting model to check the Pearson correlation coefficient and the consistency interval width. If the Pearson correlation coefficient and the consistency interval width both meet the wet film control standard, the manual decision layer is entered. The manual layer determines that the wet film control can be enabled and then executes the wet film control algorithm, otherwise it switches to dry film control. The method of the present invention establishes a dual closed-loop control system, and adopts a dual verification mechanism of the Pearson correlation coefficient and the consistency interval width to ensure the reliability of the fitting data.

Description

Technical Field

[0001] The present invention relates to the technical field of dry and wet film coordinated control, and in particular to a dry and wet film coordinated control method based on a full-detection area density scanner. Background Art

[0002] In the coating manufacturing industry, areal density uniformity is a core indicator that influences product performance. The drying process after wet film coating can cause a shift in areal density distribution due to factors such as solvent volatilization and material shrinkage. Traditionally, quality control of the wet film (undried coating) and the dry film (dried finished product) is performed independently, lacking a dynamic coordination mechanism.

[0003] The current industry-wide method for surface density control uses a mobile surface density scanner to measure the dry film's surface density. This is fed back to the die's closed-loop control software, which then adjusts the die's T-block position to control the surface density of the corresponding T-block section. Because the dry film measurement point is typically located at the end of the process flow, far from the actuator (die), this results in significant time delay and control lag. To address this control lag, a wet film surface density monitoring point is located closer to the actuator (die) in the process flow, using this wet film surface density data to aid control. This method typically uses a scanning surface density meter to measure the wet film's surface density, which is fed back to the actuator (die) closed-loop software for T-block position adjustment. While this method reduces control system latency, the wet film surface density is affected by factors such as oven temperature and heating uniformity, and often differs significantly from the final dry film surface density. Therefore, accurately matching the wet and dry film surface densities and coordinating dry and wet film control remains an unresolved technical challenge. Summary of the Invention

[0004] The problem to be solved by the present invention is to provide a dry-wet film coordinated control method to ensure that the wet film control is used to reduce the feedback delay of the coating closed-loop control while improving the reliability of the wet film surface density fitting.

[0005] In view of the shortcomings of the prior art, the present invention solves the technical problems by adopting the following technical solutions:

[0006] A dry and wet film coordinated control method based on a full-detection area density scanner comprises the following steps:

[0007] Step 1: Select the coating mode. After the system is initialized, first select the coating mode. The coating mode can be wet film coating or dry film coating. If dry film coating is selected, enter dry film control. If wet film coating is selected, enter step 2.

[0008] Step 2: Determine whether the preset coating length is reached. If not, enter dry film control; if reached, enter step 3.

[0009] Step 3: Determine whether this is the first control or the last control is dry film control. If not, proceed to dry film control. If yes, proceed to step 4.

[0010] Step 4: Online fitting: Call the original surface density of the wet film collected by the full-detection surface density scanner and the surface density of the dry film collected by the full-detection surface density scanner to perform online fitting;

[0011] Step 5: Circular check to see if the Pearson correlation coefficient and the consistency interval width meet the wet film control standard. If both the Pearson correlation coefficient and the consistency interval width meet the wet film control standard, proceed to step 6. If either the Pearson correlation coefficient or the consistency interval width does not meet the wet film control standard, proceed to dry film control.

[0012] Step 6: Select whether to perform wet film control on the interface. If yes, proceed to step 7.

[0013] Step 7: Wet film control;

[0014] The online fitting process in step 4 is as follows:

[0015] a. Collection of wet film original surface density: The full-detection surface density scanner has continuously collected the previous N wet film original surface density sets. ,

[0016] ,

[0017] b. Dry film surface density collection: The full-detection surface density scanner has continuously collected N sets of dry film surface density sets D that match the wet film. ;

[0018] c. Use linear regression model to establish the mapping relationship between dry film surface density and wet film original surface density:

[0019] ,

[0020] in is the intercept, is the slope, is the surface density of the dry film of the i-th pass, is the wet film of the i-th pass

[0021] Original areal density;

[0022] d. Obtain parameters by least squares method 、 ;

[0023] The calculation process of Pearson correlation coefficient is as follows:

[0024] ,

[0025] ,

[0026] in, is the original surface density of the wet film in the i-th pass, is the average of the original surface density of N wet films; is the dry film surface density after fitting the original surface density of the wet film of the i-th pass, is the mean surface density of the dry film after fitting the original surface density of the wet film for N times; r is the Pearson correlation coefficient;

[0027] The calculation process of the consistency interval width is as follows:

[0028] ;

[0029] ;

[0030] ;

[0031] ;

[0032] in, is the width of the consistency interval, To detect the standard deviation of the difference between the dry film surface density and the wet film original surface density fitting value, To detect the mean difference between the dry film surface density and the wet film original surface density fitting value, is the difference between the dry film surface density after fitting the original surface density of the wet film of the i-th partition and the dry film surface density of the i-th partition, t is the number of partitions, is the set of dry film surface density after fitting the original surface density of the wet film, , is the dry film surface density after fitting the original surface density of the wet film in the i-th pass.

[0033] Preferably, the specific process of dry film control is as follows:

[0034] Step 1: Obtain current dry film surface density data;

[0035] Step 2: Determine whether the average density of a single trip meets the standard; if not, proceed to step 3 for longitudinal adjustment logic; if it meets the standard, proceed to step 4 for transverse adjustment logic;

[0036] Step 3: The longitudinal adjustment logic includes calculating a target pump speed adjustment amount based on the deviation between the target area density mean and the actual area density mean, and then adjusting the screw pump speed based on the target pump speed adjustment amount; then proceeding to step 5;

[0037] Step 4: The horizontal adjustment logic includes traversing the density values ​​of each partition surface, combining the PID controller according to the density values ​​of each partition surface, and dynamically adjusting the actuator parameters of the corresponding area; then proceeding to step 5;

[0038] Step 5: Wait for the system to stabilize. After the screw pump speed or actuator is adjusted into place, the system will enter the stable waiting stage.

[0039] Step 6: Switch to wet film control after meeting the wet film control standards.

[0040] Preferably, the specific process of wet film control is as follows:

[0041] Step 1: Obtain single-pass fitting data of wet film surface density;

[0042] Step 2: traverse all channels to obtain real-time surface density measurement values;

[0043] Step 3: Determine whether the coarse adjustment threshold is exceeded; if it is exceeded, proceed to step 4 for longitudinal coarse adjustment; if it is not exceeded, proceed to step 5 for transverse fine adjustment;

[0044] Step 4: longitudinal rough adjustment. If the error between the preset partition surface density value and the target surface density value exceeds the error, the PID controller generates a compensation signal to drive the corresponding partition T block to complete the rapid correction of the longitudinal coating amount.

[0045] Step 5: Fine adjustment in the transverse direction: the coating width is divided into multiple independent control units according to the preset film area division rules. The density range of each partition is calculated to evaluate the transverse uniformity. The partition PID controller then outputs the fine adjustment amount of each die head T block to achieve accurate compensation of local thickness, thereby reducing the transverse standard deviation.

[0046] Step 6: Send the T-block adjustment amount. After completing the longitudinal coarse adjustment or the lateral fine adjustment, the system will send the T-block adjustment amount to the actuator for adjustment.

[0047] Step 7: Wait for the system to stabilize, start the process stability monitoring module, and continuously detect the key parameters of coating speed and slurry viscosity;

[0048] Step 8: Switch to dry film control. The fluctuation range of key parameters such as coating speed and slurry viscosity converges to the allowable range, and finally triggers the control mode switching instruction to smoothly switch the system from wet film control to dry film control mode, forming a complete process closed loop.

[0049] Preferably, in step 4, N is 20.

[0050] Preferably, the wet film control standard is that the Pearson correlation coefficient is greater than 0.6 and the consistency interval width is less than 3.5.

[0051] Preferably, 、 The calculation method is as follows,

[0052] ,

[0053] ,

[0054] ,

[0055] ,

[0056] in is the average of the original surface density of the first N wet films, It is the average density of the dry film surface of the first N wet film matches.

[0057] The beneficial effects of the present invention are as follows:

[0058] 1. The present invention adopts a full-detection surface density scanner

[0059] The full-inspection areal density scanner can achieve instantaneous global measurement, eliminate mechanical scanning positioning errors, ensure the temporal and spatial consistency of the original areal density of dry / wet films, and improve the accuracy of areal density matching; the full-inspection areal density scanner covers 100% of the inspection area in a single measurement, which is 3-5 times more efficient than the scanning type;

[0060] 2. Innovation in dry and wet membrane collaborative control

[0061] A dual closed-loop control system (rapid response for wet film + precise correction for dry film) is established, and a dynamic fitting model of the surface density of the first N passes is used to solve the nonlinear mapping problem caused by the difference in physical properties between dry and wet films. A dual verification mechanism of the Pearson correlation coefficient and the consistency interval width is used to ensure the reliability of the fitted surface density. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 A schematic diagram of a scanning area density scanner involved in the background technology;

[0063] Figure 2 Schematic diagram of a full-detection area density scanner involved in the method of the present invention;

[0064] Figure 3 This is a schematic diagram of the dry-wet membrane collaborative control system according to the present invention;

[0065] Figure 4 This is a logic flow chart of the dry and wet membrane collaborative control involved in the present invention;

[0066] Figure 5 This is a logic flow chart of dry film control according to the present invention;

[0067] Figure 6 This is a logic flow chart of wet film control involved in the present invention;

[0068] Figure 7 This is a correlation diagram with a Pearson correlation coefficient of -0.32 involved in the present invention;

[0069] Figure 8 This is a correlation diagram with a Pearson correlation coefficient of 0.764 involved in the present invention;

[0070] Figure 9 This is a schematic diagram of the fitting effect when the consistency interval width involved in the present invention is 4.16;

[0071] Figure 10 This is a schematic diagram of the fitting effect when the consistency interval width of the present invention is 1.93;

[0072] Explanation of the accompanying symbols: 1. integrated ray source; 2. line-constrained collimating hole; 3. linear array semiconductor detector; 4. oven; 5. coating die head. DETAILED DESCRIPTION

[0073] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are provided for purposes of illustration and description and are not intended to be exhaustive or to limit the invention to the disclosed forms. Many modifications and variations will be apparent to those skilled in the art. The embodiments are chosen and described to better illustrate the principles of the invention and its practical application, and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for specific applications.

[0074] As described in the background technology, in the existing surface density control technology, both the dry film detection point and the wet film detection point use a scanning surface density meter. The scanning surface density meter will cause inaccurate matching of the wet film and dry film surface density due to factors such as the motor repeatability positioning accuracy, resulting in the wet film control being generally unreliable; the original surface density of the wet film is difficult to synchronize with the scanning surface density meter and is affected by factors such as the drying box temperature, resulting in inaccurate fitting values ​​of the wet film and dry film surface densities and difficult to apply to surface density control. Traditional scanning surface density scanners are based on single-point or linear array sensors, which drive the probe to scan the sample surface line by line through a mechanical transmission system (such as an X-ray or laser displacement probe). The scanning path is zigzag or spiral, and the surface density needs to be collected point by point in a time-sharing manner. The measurement time increases linearly with the sample area. The present invention proposes a dry and wet film collaborative control method based on a full-detection surface density scanner. The full-detection surface density scanner uses a wide-array sensor or area array imaging technology, which can synchronously capture the surface density distribution of the entire detection area in a single measurement. The surface density is the weight per unit area, and the unit is mg / cm 2 Its characteristic is that it can complete global measurement instantly (such as CCD optical imaging or large-area beta-ray penetration detection) without the need for mechanical moving parts. Its typical application scenario is online monitoring of continuous production. In the coating process, the repeatability of the mechanical transmission system and the deformation from wet film to dry film (such as shrinkage caused by solvent evaporation and changes in substrate tension) will cause coordinate offset, which poses a challenge to data alignment. Figure 2 The figure shows a schematic diagram of a full-detection surface density scanner involved in the method of the present invention, including an integrated ray source 1, a line-constrained collimating hole 2, and a linear array semiconductor detector 3. The full-detection surface density scanner can achieve 100% coverage of the line scanning spot and 100% full detection of the surface density. Due to the instantaneous global measurement characteristics of the full-detection surface density scanner, the surface density of the wet film and the dry film have natural temporal and spatial consistency. For example, in the coating of lithium battery pole pieces, the wet film is directly correlated with the surface density of the dry film at the oven outlet after detection, and the thickness abnormality area can be quickly located. Based on the above advantages and disadvantages, as Figure 3 FIG2 is a schematic diagram of a system involved in the method of the present invention, including an oven 4 and a dry film detection point C and a wet film detection point B located on both sides of the oven 4. The length of the foil from the dry film detection point C to the wet film detection point B is m. The front end of the wet film detection point B is a coating die head. The length of the foil from the coating die head 5 to the wet film detection point B is n. In the present invention, both the dry film detection point C and the wet film detection point B are detected by a full-detection surface density scanner. The time point at which the point of action of the coating die head 5 executes a control instruction and moves to the dry film and wet film scanners is calculated based on the length m of the foil from the dry film detection point C to the wet film detection point B, the length n of the foil from the coating die head 5 to the wet film detection point B, and the foil running speed v. The original surface density of the wet film is matched with the surface density of the dry film. After the dry film surface density and the original surface density of the wet film are matched, the surface density of the dry film is inserted into the fitting model to calculate the surface density of the dry film fitted with the original surface density of the wet film. Figure 3 In the figure, S1 is the first dry film control, point A is the first dry film control point, the state of the dry film for the first adjustment, and the time at this time is T1; S2 is the first dry film control part reaching the wet film detection point. When the first dry film control point A adjusted by S1 reaches the wet film detection point B, the time at this time is T1+n / v; S3 is the first wet film control, point D is the first wet film control point. Since the wet film control requires 6 consecutive data to judge the trend, the algorithm actually calculates based on the six data after S2, and the time of the sixth data is recorded as T2; S4 is the first wet film control part reaching the dry film detection point C. The first wet film adjustment part adjusted by S3 reaches the dry film detection point C, the stroke is m+n, the coating speed is v, and at this time (m+n) / v seconds have passed from S3; S5 is the second dry film control, A1 is the second dry film control point. Since the dry film control requires 6 consecutive data to judge the trend, the algorithm actually calculates based on the six data after S4, and the time of the sixth data is recorded as T3.

[0075] Figure 4 This is a logic flow chart of dry and wet membrane collaborative control involved in the present invention, which specifically includes the following steps:

[0076] Step 1: Select the coating mode. After the system is initialized, first select the coating mode. The coating mode can be selected as wet film coating or dry film coating. Select dry film coating to enter dry film control; select wet film coating to enter step 2.

[0077] Step 2: Determine whether the preset coating length is reached. The coating length is determined according to the on-site process conditions. If the preset coating length is not reached, enter the dry film control; if the preset coating length is reached, enter step 3;

[0078] Step 3: Determine whether this is the first control or the last control was dry film control. If not (no means it is neither the first control nor the last control), enter dry film control. If yes (it means it is the first control or the last control was dry film control), perform online fitting of the original surface density of the wet film.

[0079] Step 4: Online fitting: The original surface density of the wet film collected by the full-detection surface density scanner and the surface density of the dry film collected by the full-detection surface density scanner are used to perform online fitting. The value of N depends on the judgment of the process personnel on the effect of the wet film surface density fitting under actual conditions.

[0080] The online fitting process in step 4 is as follows:

[0081] a. Collection of wet film original surface density: The full-detection surface density scanner has continuously collected N sets of wet film original surface density data. ,

[0082] ;

[0083] b. Dry film surface density collection: The full-detection surface density scanner has continuously collected N sets of dry film surface density sets D that match the wet film.

[0084] ;

[0085] c. Use linear regression model to establish the mapping relationship between dry film surface density and wet film original surface density:

[0086] ,

[0087] in is the intercept, is the slope, is the surface density of the dry film of the i-th pass, is the original surface density of the wet film in the i-th pass;

[0088] d. Obtain parameters by least squares method 、 ;

[0089] 、 The calculation method is as follows:

[0090] ,

[0091] ,

[0092] ,

[0093] ,

[0094] in, is the original surface density of the wet film in the i-th pass, is the average of the original surface density of the first N wet films, is the surface density of the dry film of the i-th pass, It is the average density of the dry film surface of the first N wet film matches.

[0095] Assume that 20 passes of dry film surface density and its corresponding wet film original surface density are used for online fitting, that is, when N=20, the online fitting process is as follows:

[0096] Collection of wet film original surface density: The full-detection surface density scanner has continuously collected the original surface density of the wet film for the previous 20 passes. , recorded as:

[0097] ,

[0098] Dry film surface density collection: The full-detection surface density scanner has continuously matched the original surface density of the wet film for 20 passes. The dry film surface density set D is recorded as:

[0099] ,

[0100] right 、 The linear regression model is used to establish the mapping relationship between the dry film surface density and the original wet film surface density:

[0101] ,

[0102] in is the intercept, is the slope.

[0103] Obtaining parameters by least squares method 、 :

[0104] ,

[0105] ,

[0106] ,

[0107] ,

[0108] in The average original surface density of the first 20 wet films, The average density of the dry film surface from 20 passes matching the wet film.

[0109] Step 5: Circular check to see if the Pearson correlation coefficient and consistency interval width meet the wet film control standard. The wet film control standard is that the Pearson correlation coefficient is greater than 0.6 and the consistency interval width is less than 3.5. If either the Pearson correlation coefficient or the consistency interval width does not meet the wet film control standard, the process proceeds to dry film control. If both the Pearson correlation coefficient and the consistency interval width meet the wet film control standard, the process proceeds to step 6.

[0110] Step 6: Select whether to perform wet film control on the interface. If yes, proceed to step 7.

[0111] Step 7: Wet film control.

[0112] After system initialization, the system first selects a coating start mode, which can be either wet or dry film. If wet film is selected, the system then determines whether the preset coating start length has been reached. This length is related to the accuracy of the wet film's original surface density and can be selected appropriately based on the process. If the preset wet film start length is reached, the system enters the wet film control process; if not, the system enters the dry film control process.

[0113] After executing the wet film control strategy, it is determined whether it is the first control or the last control is dry film control. If one condition is met, the surface density collaborative fitting process is activated, and the full-inspection surface density scanner is called to collect the original surface density of the wet film for the first 20 times and the surface density of the dry film for the first 20 times to perform online fitting and establish a dry-wet film parameter mapping model.

[0114] Perform cyclic verification on the fitting model, focusing on checking the Pearson correlation coefficient r (Pearson correlation coefficient measures the linear correlation of surface density) and the width of the consistency interval (Width of consistency interval Characterizes the tolerance range of prediction deviation), if the Pearson correlation coefficient r and the consistency interval width If the wet film control standard is met, the process enters the manual decision-making layer, where a human judges whether the current process meets the wet film control standard. The manual layer determines that wet film control can be enabled and then executed, otherwise it switches to dry film control.

[0115] Figure 7 Middle orange line S1, Figure 8 Middle orange line S 11 is the dry film surface density curve (the dry film surface density curve comes from the surface density data sent by the surface density scanner at the dry film detection point), Figure 7 Medium blue line S2, Figure 8 Medium blue line S 22 Fitting curve for wet film surface density data (wet film surface density data comes from the data sent by the surface density scanner at the wet film detection point), where Figure 7 The Pearson correlation coefficient r is -0.32, Figure 8 The Pearson correlation coefficient r is 0.764, which shows that Figure 8 The dry film curve fitted by the medium-wet film has a strong correlation with the actual dry film curve trend. Figure 7 The correlation is weaker. Generally speaking, the closer the Pearson correlation coefficient r is to 1, the stronger the positive correlation is. Therefore, the latest Pearson correlation coefficient r will be tested in wet film control to determine whether the fitting effect of the original surface density of the current wet film is suitable for wet film control.

[0116] The calculation process of Pearson correlation coefficient r is as follows:

[0117] The Pearson correlation coefficient r is a core indicator for measuring the linear correlation between two sets of data. In this invention, the Pearson correlation coefficient r is defined as the ratio of the covariance to the standard deviation:

[0118] ,

[0119] ,

[0120] in, is the original surface density of the wet film in the i-th pass, is the average of the original surface density of N wet films; is the dry film surface density after fitting the original surface density of the wet film of the i-th pass, is the mean dry film surface density after N passes of wet film original surface density fitting; the closer r is to 1, the stronger the linear positive correlation between the dry film surface density after fitting based on the wet film original surface density and the actual measured dry film surface density. The dry film surface density set after wet film fitting is , is the dry film surface density after fitting the original surface density of the wet film of the i-th pass, and the actual detected dry film surface density set is D.

[0121] Figure 9 The orange line in the middle is the actual detected dry film surface density curve S3, Figure 10 The orange line in the middle is the actual detected dry film surface density curve S 33 , Figure 9 Medium blue line S4, Figure 10 Medium blue line S 44 is the curve fitted to the wet film surface density data, where Figure 9 The consistency interval of S3 and S4 is [-1.15, 3.01], and the width of the consistency interval is 4.16, indicating that compared with the surface density of the dry film, the difference in the wet film fitting surface density fluctuates greatly, the standard deviation of the difference is large, and the fitting effect is poor. Figure 10 S in 33 、S 44The consistency interval is [-1.17, 0.76], the consistency interval width is 1.93, the difference range is narrower, and the standard deviation of the difference is smaller, indicating that the wet film fitting value is more accurate. Therefore, the latest consistency interval width will be tested in wet film control. , in order to judge whether the fitting effect of the original surface density of the current wet film is suitable for wet film control.

[0122] Width of consistency interval The calculation process is as follows:

[0123] The dry film surface density set after wet film fitting is , ,

[0124] The actual detection dry film surface density set is D, , the number of partitions is t, and the difference between the fitted value of the wet film surface density of each partition and the detected dry film surface density is calculated :

[0125] ,

[0126] Then the mean difference between the dry film surface density and the wet film surface density fitting value is detected for:

[0127] ,

[0128] Detect the standard deviation of the difference between the dry film surface density and the wet film surface density fitting value for:

[0129] ,

[0130] The width of the consistency interval for:

[0131] .

[0132] Figure 5 The present invention relates to a dry film control logic flow chart, which specifically includes the following steps:

[0133] Step 1: Get the current dry film surface density data (the dry film detection point full inspection surface density scanner has been sent);

[0134] Step 2: Determine whether the average density of a single trip meets the standard; if not, proceed to step 3 for longitudinal adjustment logic; if it meets the standard, proceed to step 4 for transverse adjustment logic;

[0135] Step 3: The longitudinal adjustment logic includes calculating a target pump speed adjustment amount based on the deviation between the target area density mean and the actual area density mean, and then adjusting the screw pump speed based on the target pump speed adjustment amount; then proceeding to step 5;

[0136] Step 4: The horizontal adjustment logic includes traversing the density values ​​of each partition surface, combining the PID controller according to the density values ​​of each partition surface, and dynamically adjusting the actuator parameters of the corresponding area; then proceeding to step 5;

[0137] Step 5: Wait for the system to stabilize. After the screw pump speed or actuator is adjusted into place, the system will enter the stable waiting stage.

[0138] Step 6: Switch to wet film control after meeting the wet film control standards.

[0139] The dry film control logic process begins by acquiring the current dry film surface density data, then determining whether the single-pass surface density average meets the standard. If the single-pass surface density average meets the preset threshold range, the system enters the lateral adjustment logic. By traversing the measured surface density values ​​of each section of the coating area, the actuator parameters of the corresponding area are dynamically adjusted in conjunction with the PID controller. If the single-pass surface density average does not meet the standard, the system switches to the longitudinal adjustment logic. First, the target pump speed adjustment amount of the screw pump is calculated based on the deviation between the target surface density average and the actual surface density average, and then the pump speed adjustment mechanism is driven to complete the longitudinal overall coating amount correction. After completing the lateral or longitudinal adjustment operation, the system enters a stable waiting phase and switches to wet film control when the wet film control standard is met.

[0140] Figure 6 This is a logic flow chart of wet film control involved in the present invention, which specifically includes the following process:

[0141] Step 1: According to Figure 3 After the system obtains the original surface density of the wet film and the corresponding surface density of the dry film, it performs fitting calculation on the original surface density of the wet film and the corresponding surface density of the dry film to obtain the single-pass fitting surface density of the wet film;

[0142] Step 2: traverse the wet film fitting surface density of all channels to obtain the real-time wet film fitting value;

[0143] Step 3: Determine whether the coarse adjustment threshold is exceeded; if it is exceeded, proceed to step 4 for longitudinal coarse adjustment; if it is not exceeded, proceed to step 5 for transverse fine adjustment;

[0144] Step 4: longitudinal rough adjustment. If the error between the preset partition surface density value and the target surface density value exceeds the error, the PID controller generates a compensation signal to drive the corresponding partition T block to complete the rapid correction of the longitudinal coating amount.

[0145] Step 5: Transverse fine adjustment: Divide the coating width into multiple independent control units according to the preset film area division rules, calculate the surface density range of each partition to evaluate the transverse uniformity, and then use the partition PID controller to output the fine adjustment amount of each T block respectively to achieve accurate compensation of local thickness, thereby reducing the transverse standard deviation;

[0146] Step 6: Send the T-block adjustment amount. After completing the longitudinal coarse adjustment or the lateral fine adjustment, the system will send the T-block adjustment amount to the actuator for adjustment.

[0147] Step 7: Wait for the system to stabilize, start the process stability monitoring module, and continuously detect key parameters such as coating speed and slurry viscosity;

[0148] Step 8: Switch to dry film control. The fluctuation range of key parameters such as coating speed and slurry viscosity converges to the allowable range, and finally triggers the control mode switching instruction to smoothly switch the system from wet film control to dry film control mode, forming a complete process closed loop.

[0149] The wet film control logic process starts with the acquisition of the single-pass fitting surface density of the wet film. The system first traverses the real-time surface density measurement values ​​of all channels, and then enters the adjustment threshold judgment link: the diamond decision box is used to determine whether the current surface density distribution exceeds the preset coarse adjustment threshold range. If it exceeds the threshold (Y branch), the longitudinal coarse adjustment mechanism is activated. The error between the preset partition surface density value and the target value is generated through the PID controller to generate a compensation signal to drive the corresponding partition T block to complete the rapid correction of the longitudinal coating amount; if it does not exceed the threshold (N branch), it enters the transverse fine adjustment stage, and the coating width is divided into multiple independent control units according to the preset film area division rules. The surface density range of each partition is calculated to evaluate the transverse uniformity, and then the partition PID controller is used to output the fine adjustment amount of each T block respectively to achieve accurate compensation of local thickness, thereby reducing the transverse standard deviation. After completing the longitudinal or lateral adjustment, the system will send the T-block adjustment amount to the actuator and simultaneously start the process stability monitoring module to continuously detect key parameters such as coating speed and slurry viscosity until their fluctuation amplitude converges to the allowable range. Finally, the control mode switching instruction is triggered to smoothly transition the system from the wet film dynamic adjustment state to the dry film steady-state control mode, forming a complete process closed loop.

Claims

1. A dry and wet film coordinated control method based on a full-detection areal density scanner, characterized by: The following steps are included: Step 1: Select the coating mode. After the system is initialized, first select the coating mode. The coating mode can be wet film coating or dry film coating. If dry film coating is selected, enter dry film control. If wet film coating is selected, enter step 2. Step 2: Determine whether the preset coating length is reached. If not, enter dry film control; if reached, enter step 3. Step 3: Determine whether this is the first control or the last control is dry film control. If not, proceed to dry film control. If yes, proceed to step 4. Step 4: Online fitting: Call the original surface density of the wet film collected by the full-detection surface density scanner and the surface density of the dry film collected by the full-detection surface density scanner to perform online fitting; Step 5: Circular check to see if the Pearson correlation coefficient and the consistency interval width meet the wet film control standard. If both the Pearson correlation coefficient and the consistency interval width meet the wet film control standard, proceed to step 6. If either the Pearson correlation coefficient or the consistency interval width does not meet the wet film control standard, proceed to dry film control. Step 6: Select whether to perform wet film control on the interface. If yes, proceed to step 7. Step 7: Wet film control; The online fitting process in step 4 is as follows: a. Collection of wet film original surface density: The full-detection surface density scanner has continuously collected the previous N wet film original surface density sets. , ， b. Dry film surface density collection: The full-detection surface density scanner has continuously collected N sets of dry film surface density sets D that match the wet film. ; c. Use linear regression model to establish the mapping relationship between dry film surface density and wet film original surface density: ， in is the intercept, is the slope, is the surface density of the dry film of the i-th pass, is the original surface density of the wet film in the i-th pass; d. Obtain parameters by least squares method 、 ; The calculation process of Pearson correlation coefficient is as follows: ， ， in, is the original surface density of the wet film in the i-th pass, is the average of the original surface density of N wet films; is the dry film surface density after fitting the original surface density of the wet film of the i-th pass, is the mean dry film surface density after N passes of wet film original surface density fitting; r is the Pearson correlation coefficient; The calculation process of the consistency interval width is as follows: ； ； ； ； in, is the width of the consistency interval, To detect the standard deviation of the difference between the dry film surface density and the wet film original surface density fitting value, To detect the mean difference between the dry film surface density and the wet film original surface density fitting value, is the difference between the dry film surface density after fitting the original surface density of the wet film of the i-th partition and the dry film surface density of the i-th partition, t is the number of partitions, is the set of dry film surface density after fitting the original surface density of the wet film, , is the dry film surface density after fitting the original surface density of the wet film in the i-th pass.

2. The dry and wet film coordinated control method based on the full-detection areal density scanner according to claim 1 is characterized in that: The specific process of dry film control is as follows: Step 1: Obtain current dry film surface density data; Step 2: Determine whether the average density of a single trip meets the standard; if not, proceed to step 3 for longitudinal adjustment logic; if it meets the standard, proceed to step 4 for transverse adjustment logic; Step 3: The longitudinal adjustment logic includes calculating a target pump speed adjustment amount according to a deviation between the target area density mean and the actual area density mean, and then adjusting the screw pump speed according to the target pump speed adjustment amount; Then proceed to step five; Step 4: The horizontal adjustment logic includes traversing the density values ​​of each partition surface, combining the PID controller according to the density values ​​of each partition surface, and dynamically adjusting the actuator parameters of the corresponding area; then proceeding to step 5; Step 5: Wait for the system to stabilize. After the screw pump speed or actuator is adjusted into place, the system will enter the stable waiting stage. Step 6: Switch to wet film control after meeting the wet film control standards.

3. The dry and wet film coordinated control method based on a full-detection areal density scanner according to claim 1, characterized in that: The specific process of wet film control is as follows: Step 1: Obtain single-pass fitting data of wet film surface density; Step 2: traverse all channels to obtain real-time surface density measurement values; Step 3: Determine whether the coarse adjustment threshold is exceeded; If the threshold is exceeded, the process goes to step 4 for longitudinal coarse adjustment; if the threshold is not exceeded, the process goes to step 5 for transverse fine adjustment. Step 4: longitudinal rough adjustment. If the error between the preset partition surface density value and the target surface density value exceeds the error, the PID controller generates a compensation signal to drive the corresponding partition T block to complete the rapid correction of the longitudinal coating amount. Step 5: Fine adjustment in the transverse direction: the coating width is divided into multiple independent control units according to the preset film area division rules. The density range of each partition is calculated to evaluate the transverse uniformity. The partition PID controller then outputs the fine adjustment amount of each die head T block to achieve accurate compensation of local thickness, thereby reducing the transverse standard deviation. Step 6: Send the T-block adjustment amount. After completing the longitudinal coarse adjustment or the lateral fine adjustment, the system will send the T-block adjustment amount to the actuator for adjustment. Step 7: Wait for the system to stabilize, start the process stability monitoring module, and continuously detect the key parameters of coating speed and slurry viscosity; Step 8: Switch to dry film control. The fluctuation range of key parameters such as coating speed and slurry viscosity converges to the allowable range, and finally triggers the control mode switching instruction to smoothly switch the system from wet film control to dry film control mode, forming a complete process closed loop.

4. The dry and wet film coordinated control method based on a full-detection areal density scanner according to claim 1, characterized in that: In step 4, N is 20.

5. The dry and wet film coordinated control method based on a full-detection areal density scanner according to claim 1, characterized in that: The wet film control criteria are a Pearson correlation coefficient greater than 0.6 and a consistency interval width less than 3.

5.

6. The dry and wet film coordinated control method based on a full-detection areal density scanner according to claim 1, characterized in that: 、 The calculation method is as follows, ， ， , , in is the average of the original surface density of the first N wet films, It is the average density of the dry film surface of the first N wet film matches.

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