A coating and rolling closed-loop adjustment method

Abstract

The present invention relates to the technical field of lithium batteries, and particularly to a coating and rolling closed-loop adjustment method, which is characterized by including the following steps: closed-loop switch control for determining whether to turn on the closed-loop adjustment; closed-loop adjustment of the pressure / pump speed of the coater; closed-loop adjustment of the pressure / position of the rolling machine. By using the surface density / thickness of the product to be detected scanned in real time and through closed-loop logical operation, the parameters of the coating / rolling equipment are controlled or corrected in real time, the stability of the coating / rolling equipment is improved, and at the same time, the surface density / thickness of the product is controlled in reverse, thereby improving the quality of the product to be detected by coating / rolling and reducing the product rejection rate.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium batteries, and specifically to a coating and rolling closed-loop adjustment method. Background Art

[0002] The general technological process for manufacturing lithium battery electrodes is as follows: active materials, binders, conductive agents, etc. are mixed to prepare a slurry, which is then coated on both sides of a copper or aluminum current collector. After drying, the solvent is removed to form a lithium battery electrode. The particle coating of the lithium battery electrode is compacted and densified, and then cut or slit. Rolling is the most commonly used compaction process for lithium battery electrodes. Generally, a pair of rollers is used for continuous rolling compaction. During this process, the lithium battery electrode with particle coatings on both sides is fed into the gap between the two rollers, and the coating is compacted under the action of the rolling line load.

[0003] During the actual production of lithium battery electrodes, during the acceleration, constant speed, and deceleration processes of coating / rolling, due to the instability of the coating / rolling equipment, the quality of the lithium battery electrodes decreases, and even scrapping may occur. Summary of the Invention

[0004] The purpose of the present invention is to provide a coating and rolling closed-loop adjustment method to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A coating and rolling closed-loop adjustment method, characterized by including the following steps:

[0006] Closed-loop switch control, used to determine whether to enable closed-loop adjustment;

[0007] Closed-loop adjustment of the pressure / pump speed of the coater;

[0008] Closed-loop adjustment of the pressure / position of the rolling machine.

[0009] Further, the closed-loop switch control includes the following steps:

[0010] Web speed limit: A speed limit threshold Yl is set. If the web speed Ys < Yl, adjustment can be performed; otherwise, it cannot be performed.

[0011] Distance Dt between the control point and the detection device: When the web length Yp at the current scanning position and the equal web length ≥ Yp + Dt, adjustment can be performed; otherwise, adjustment cannot be performed.

[0012] Adjustment period Rp: The surface density meter or thickness gauge scans Rp times for closed-loop adjustment once.

[0013] Speed fluctuation detection:

[0014] When Ysv - Ys ≤ D, it indicates a constant speed and adjustment can be performed;

[0015] When Ysv - Ys > D, it indicates that it is not a constant speed and no adjustment is performed;

[0016] Among them, Ys is the current speed value, Ysv is the average value of the previous N speed values, the acquisition time interval is S, and D is the speed fluctuation range.

[0017] Furthermore, the closed-loop regulation of the coater pressure / pump speed and the closed-loop regulation of the roll press pressure / position both include the following steps:

[0018] The product to be detected is scanned by a detection device to obtain scan data;

[0019] According to the scan data, calculate the adjustment amount of the coater pressure / pump speed or the roll press pressure / position.

[0020] Furthermore, the calculation method of the adjustment amount of the coater pressure / pump speed and the pressure / position on both axial sides of the roll press is a multi-step coefficient calculation method:

[0021] Calculate the weighted average value of the nth scan data:

[0022] Av = (Av1 + Av2 + … + Avn) / Wtn,

[0023] Among them, Av is the weighted average value of the scan data, Wtn is the number of times of weighted average n times, and Wt ≥ 1, which is used to control the number of times of data superposition averaging of the average value Av of parameter adjustment, and Av1, Av2, Av3…Avn are the average values of the n scan data of the detection device;

[0024] Calculate the difference between the weighted average value of the scan data and the target value: Dv = Tv - Av,

[0025] Among them, Tv is the target value of the parameter corresponding to the product scan data, and Dv is the difference between the weighted average value of the scan data and the target value;

[0026] When it satisfies: |Dv| < Ld1, the adjustment amount: Aa = Cp + Dv * 0 / Aa = Dv * 0,

[0027] When it satisfies: Ld1 ≤ |Dv| < Ud, the adjustment amount: Aa = Cp + Dv * Kp / Aa = Dv * Kp,

[0028] When it satisfies: |Dv| > Ud, the adjustment amount: Aa = Cp + Ud1 * Kp / Aa = Ud * Kp,

[0029] Among them, Aa is the overall adjustment amount of the equipment, Cp is the current parameter of the equipment, Kp is the adjustment coefficient, Ud is the upper limit of the difference between the average value of the scan data and the target value of the product to be detected, Ld is the lower limit of the difference between the average value of the scan data and the target value of the product to be detected, Ld1~Ud is a single range or a continuous multiple range value, and Kp is different when Dv is in different ranges.

[0030] Further, Aa is the pressure / pump speed adjustment amount of the coater screw pump, Cp is the current pressure / pump speed of the coater screw pump, the detection device is a basis weight meter, the scan data is the basis weight of the product to be detected, Av is the average basis weight, Tv is the target basis weight, and Dv is the difference between the average basis weight and the target value.

[0031] Further, Aa is the pressure / position adjustment amount of the roll press, Cp is the current pressure / position of the roll press, the detection device is a thickness gauge, the scan data is the split thickness of the left and right sides of the product to be roll-pressed, there are two groups of Av, and the two Avs are respectively the average values of the split thickness of the left and right sides of the product to be detected, Tv is the target thickness of the product to be detected, Dv is the difference between the average thickness and the target value, and the pressure / position adjustment amounts on the left and right sides of the axial direction of the roll press are calculated respectively.

[0032] Further, the adjustment of the pressure / position on both sides of the axial direction of the roll press further includes speed closed-loop adjustment, and the speed closed-loop adjustment includes:

[0033] S1: Collect the low-speed A value;

[0034] S2: After collecting the A value, collect the high-speed B value;

[0035] S3: Calculate the pressure / position compensation amount of the roll press.

[0036] Further, collecting the low-speed A value includes the following steps:

[0037] S11: When Ld2 - Lt ≤ LYs ≤ Ld2 + Lt and |D| ≤ Df, collect the A value. When LYs < Ld2 - Lt, Ys > Ld2 + Lt or |D| > Df, do not collect the A value;

[0038] S12: When the conditions of S11 are met, multiple A values will be continuously collected, and the last A value is taken as the final value;

[0039] Among them, LYs is the low-speed running speed of the roll press, Ld2 is the speed target value for collecting A data at low speed, Lt is the fluctuation range of the target speed when collecting A at low speed, D is the difference between the target value and the measured value of the product thickness, and Df is the allowable fluctuation range of the difference between the target value and the measured value of the product thickness;

[0040] Collecting the high-speed B value includes the following steps:

[0041] S21: When Hd2 - Ht ≤ HYs ≤ Hd2 + Ht and |D| ≤ Df, collect the B value. When HYs < Hd2 - Ht, Ys > Hd2 + Ht or |D| > Df, do not collect the B value;

[0042] S22: When the condition of S21 is met, only the first B value is taken as the final value;

[0043] Among them, HYs is the high-speed running speed of the roller press, Hd2 is the speed target value for collecting B data at high speed, Ht is the fluctuation range of the target speed when collecting B at high speed, D is the difference between the target value and the measured value of the product thickness, and Df is the allowable fluctuation range of the difference between the target value and the measured value of the product thickness.

[0044] Furthermore, the calculation formula for the pressure / position compensation amount on both sides of the roller press is a multi-step coefficient calculation method:

[0045] nLa = T * Kp(2n - 1);

[0046] nHa = T * Kp2n;

[0047] T = B - A;

[0048] Kp1 + Kp2 + Kp3 + …… + Kpn = 1;

[0049] Among them, nLa is the pressure / position adjustment amount of the roller press at the nth low speed, nHa is the pressure / position adjustment amount of the roller press at the nth high speed, and Kpn is the adjustment coefficient of the nth order;

[0050] Furthermore, the calculation method for calculating the adjustment amount of the pressure / pump speed of the coater or the pressure / position on both axial sides of the roller press is PID adjustment calculation:

[0051]

[0052] Original + adjustment amount adjustment: u t = u t-1 + Δu t ,

[0053] Adjustment amount adjustment: u t = Δu t ,

[0054] ΔP t = u t ,

[0055] P t = P t-1 + ΔP t ,

[0056] Among them, Δu t is the output increment of the PID controller,

[0057] Kp: Adjustment coefficient,

[0058] e t : The error between the target value and the actual value of the detection data at the current moment,

[0059] e t-1 : The error between the target value and the actual value of the detection data at the current moment for the previous time.

[0060] e t-2 : The error between the target value and the actual value of the detection data at the current moment for the two previous times.

[0061] Ti: The integral time constant.

[0062] T d : The differential time constant.

[0063] u t : The output of the PID controller.

[0064] ΔP t : The output increment at time t.

[0065] tP t : The roll position output at the moment.

[0066] Compared with the prior art, the beneficial effects of the present invention are as follows: The coating and rolling closed-loop adjustment method utilizes the surface density / thickness of the product to be detected scanned in real time, and through closed-loop logical operation, the parameters of the coating / rolling equipment are controlled or corrected in real time, improving the stability of the coating / rolling equipment, thereby improving the quality of the coating / rolling product to be detected and reducing the product rejection rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is the system block diagram of the present invention;

[0068] Figure 2 It is the structural schematic diagram of the coater of the present invention;

[0069] Figure 3 It is the structural schematic diagram of the rolling machine of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0070] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0071] Please refer to Figure 1 , an embodiment provided by the present invention: A coating and rolling closed-loop adjustment method, characterized by including the following steps:

[0072] Closed-loop switch control, used to determine whether to enable closed-loop adjustment;

[0073] Closed-loop regulation of coater pressure / pump speed;

[0074] Closed-loop regulation of roll press pressure / position.

[0075] Closed-loop switch control, including the following steps:

[0076] Closed-loop regulation enable flag address of the basis weight meter: Reading the specified register of the PLC programmable controller as: 1 / True, perform regulation, otherwise do not perform;

[0077] Closed-loop regulation end flag address of the thickness gauge: Reading the specified register of the PLC programmable controller as: 0 / False, perform regulation, otherwise do not perform;

[0078] Web running speed limit: A speed limit threshold Yl is set. When the web running speed Ys < Yl, regulation can be performed, otherwise not. Further, Yl ≥ 0, unit: m / min, and its specific value is determined according to the actual situation of the equipment;

[0079] Distance Dt between the control point and the detection device: For the current scanning position, when the web running length Yp of the roll is such that the equal roll length ≥ Yp + Dt, regulation can be performed, otherwise not. Specifically, Dt ≥ 0, unit: mm. In this embodiment, the product is a battery electrode tab. In the coater, the detection device is the basis weight meter, and the distance between the control point and the basis weight meter is the distance from the lip of the coating die to the center of the basis weight meter. In the roll press, the detection device is the thickness gauge, and the distance between the control point and the thickness gauge is the distance from the contact line of the upper and lower pressure rolls with the product to the center of the thickness gauge;

[0080] Regulation period Rp: The basis weight meter or the thickness gauge performs closed-loop regulation once every Rp scans. Rp is also determined according to the actual situation of the equipment;

[0081] Speed fluctuation detection: Judging whether the web running speed is a constant speed based on the equipment speed collected according to the set conditions,

[0082] When Ysv - Ys ≤ D, it indicates a constant speed and regulation can be performed,

[0083] When Ysv - Ys > D, it indicates a non-constant speed and regulation is not performed;

[0084] Among them, Ys is the current speed value, Ysv is the average value of the previous N speed values, the acquisition time interval is S, and D is the speed fluctuation range. The specific data of D is obtained based on experiments or experience;

[0085] The specific calculation method is as follows:

[0086] Let N = 3, the first speed: Ys1, the second speed: Ys2, the third speed: Ys3, the fourth speed: Ys4, S = 1000, indicating that the acquisition interval of Ys is 1000 ms,

[0087] When |(Ys1 + Ys2 + Ys3)÷3 - Ys4| ≤ D, it indicates a constant speed and adjustment can be executed.

[0088] When |(Ys1 + Y2 + Ys3)÷3 - Ys4| > D, it indicates a non-constant speed and adjustment is not executed.

[0089] The closed-loop regulation of the coater pressure / pump speed and the closed-loop regulation of the roll press pressure / position both include the following steps.

[0090] Scan the product to be detected through a detection device to obtain scan data.

[0091] Calculate the adjustment amount of the coater pressure / pump speed or the roll press pressure / position based on the scan data.

[0092] Furthermore, please refer to Figure 2 , the closed-loop regulation of the coater pressure / pump speed includes the following steps.

[0093] Scan the product to be detected through a surface density meter to obtain surface density data.

[0094] Calculate the adjustment amount of the coater pressure / pump speed based on the surface density data.

[0095] Specifically, the calculation method for calculating the adjustment amount of the coater pressure / pump speed is any one of the following:

[0096] (1) Multi-step coefficient calculation method:

[0097] First, calculate the weighted average value of the nth surface density data:

[0098] Av = (Av1 + Av2 + … + Avn) / Wtn,

[0099] where Av is the weighted average value of the surface density data, Wtn is the weighted average number of n times, and Wt ≥ 1, which is used to control the average number of times Av data of parameter adjustment is superimposed and averaged. Av1, Av2, Av3…Avn are the average values of the nth surface density data of the surface density meter. For example:

[0100] Let the weighted average number Wtn = 3,

[0101] The average values of the nth surface density data are: Av1, Av2, Av3, Av4……Avn,

[0102] For the 1st time: Do not calculate.

[0103] For the 2nd time: Do not calculate.

[0104] For the 3rd time: 3Av = (Av1 + Av2 + Av3) / 3,

[0105] The 4th time: 4Av = (Av2 + Av3 + Av4) / 3,

[0106] ……

[0107] The nth time: nAv = (Avn-2 + Avn-1 + Avn) / 3;

[0108] Let the weighted average number of times Wtn = 4,

[0109] The average value of the surface density data for n times is: Av1, Av2, Av3, Av4... Avn,

[0110] The 1st time: Not calculated,

[0111] The 2nd time: Not calculated,

[0112] The 3rd time: Not calculated,

[0113] The 4th time: 4Av = (Av1 + Av2 + Av3 + Av4) / 4,

[0114] The 5th time: 5Av = (Av2 + Av3 + Av4 + Av5) / 4,

[0115] ……

[0116] The nth time: nAv = (Avn-3 + Avn-2 + Avn-1 + Avn) / 4;

[0117] Then calculate the difference between the weighted average value of the surface density data and the target value: Dv = Tv - Av,

[0118] where Tv is the target value of the product surface density data, and Dv is the difference between the weighted average value of the surface density data and the target value;

[0119] When it satisfies: |Dv| < 1Ld1, the adjustment amount: Aa = Cp + Dv * 0 / Aa = Dv * 0,

[0120] When it satisfies: 1Ld1 ≤ |Dv| < 1Ud, the adjustment amount: Aa = Cp + Dv * Kp1 / Aa = Dv * Kp1,

[0121] When it satisfies: 2Ld1 ≤ |Dv| < 2Ud, the adjustment amount: Aa = Cp + Dv * Kp2 / Aa = Dv * Kp2,

[0122] When it satisfies: 3Ld1 ≤ |Dv| < 3Ud, the adjustment amount: Aa = Cp + Dv * Kp3 / Aa = Dv * Kp3,

[0123] When it satisfies: |Dv| > 3Ud, the adjustment amount: Aa = Cp + 3Ud * Kp3 / Aa = 3Ud * Kp3,

[0124] The above settings satisfy the following conditions: 1Ld1 < 1Ud = 2Ld1 < 2Ud = 3Ld1 < 3Ud,

[0125] where Aa is the overall adjustment amount of the pressure / pump speed of the coater screw pump, Cp is the current parameter of the coater screw pump, Kp is the adjustment coefficient, Ud is the upper limit of the difference between the average value of the surface density data and the target value of the product to be detected, and Ld1 is the lower limit of the difference between the average value of the surface density data and the target value of the product to be detected. Specifically, the calculation method of the multi-step coefficient can be set from 1 to n steps. In this embodiment, 1Ld1, 1Ud, 2Ld1, 2Ud, 3Ld1, and 3Ud are only for illustrative purposes, used to distinguish the upper and lower limits of the difference between the weighted average value of the surface density data and the target value. Their specific values and the specific values of Kp1, Kp2, and Kp3 are obtained through experiments or experience. Ld1, Ud, and Kp can also be set to other parameters. When the difference Dv between the weighted average value of the surface density data and the target value is in different regions, different formulas are used to calculate the overall adjustment amount of the pressure / pump speed of the coater screw pump;

[0126] The Kp adjustment coefficient specifically refers to the coefficient that converts the surface density to the coater pressure / pump speed. For example, when the pump speed is increased by 1 and the surface density is increased by 2, then Kp = 1 / 2 = 0.5. In short, it can be considered how much the coater pressure / pump speed changes corresponding to a change in the surface density by 1. Its specific value can be obtained through experiments or experience;

[0127] (2) PID adjustment calculation:

[0128]

[0129] Original + adjustment amount adjustment: u t = u t-1 + Δu t ,

[0130] Adjustment amount adjustment: u t = Δu t ,

[0131] ΔP t = u t ,

[0132] P t = P t-1 + ΔP t ,

[0133] where Δu t is the output increment of the PID controller,

[0134] Kp: adjustment coefficient,

[0135] e t: The error between the target value and the actual value of the surface density data at the current moment,

[0136] e t-1 : The error between the previous target value and the actual value of the surface density data at the current moment,

[0137] e t-2 : The error between the target value of the surface density data at the current moment and the actual value of the surface density data two times ago,

[0138] Ti: The integral time constant,

[0139] T d : The differential time constant,

[0140] u t : The output of the PID controller,

[0141] ΔP t : The output increment at time t,

[0142] P t : The roll position output at time t.

[0143] Furthermore, please refer to Figure 3 , the pressure / position closed-loop regulation of the roll press includes the following steps:

[0144] Scan the product to be detected with a thickness gauge to obtain thickness data;

[0145] Calculate the adjustment amount of the pressure / position of the roll press according to the thickness data.

[0146] Specifically, cylinders for adjusting the pressure on both sides are respectively arranged on the left and right sides of the roll press along its axial direction. The product is divided into two strips, strip 1 and strip 2. Calculate the adjustment amounts of the pressure / position on the left and right sides of the axial direction of the roll press respectively according to the thickness data of strip 1 and strip 2;

[0147] The calculation method of the adjustment amount of the pressure / position of the roll press is a multi-step coefficient calculation method. The adjustment amounts of the pressure / position on the left and right sides of the axial direction of the roll press are calculated separately. The multi-step coefficient calculation method of the adjustment amount of the pressure / position on the left side of the roll press is specifically:

[0148] Calculate the weighted average value of the thickness of the nth time of strip 1 on the left side:

[0149] Av = (Av1 + Av2 + … + Avn) / Wtn,

[0150] where Av is the weighted average value of the thickness data of strip 1, Wtn is the number of weighted average times n times, and Wt≥1, which is used to control the average number of times Av data of parameter adjustment is superimposed and averaged. Av1, Av2, Av3…Avn are the average values of the thickness data of strip 1 measured by the thickness gauge n times, and their specific calculation methods are the same as the calculation method of the above density data;

[0151] Next, calculate the difference Ld = Tv - Av between the weighted average of the thickness data of the left strip 1 and the target value,

[0152] where Tv is the target value of the product thickness, and Ld is the difference between the weighted average of the thickness data of the left strip 1 and the target value;

[0153] When the condition |Ld| < 1Lld is satisfied, the adjustment amount: La = Lp + Ld * 0 / La = Ld * 0,

[0154] When the condition 1Lld ≤ |Ld| < 1Lud is satisfied, the adjustment amount: La = Lp + Ld * LKp1 / La = Ld * LKp1,

[0155] When the condition 2Lld ≤ |Ld| < 2Lud is satisfied, the adjustment amount: La = Lp + Ld * LKp2 / La = Ld * LKp2,

[0156] When the condition 3Lld ≤ |Ld| < 3Lud is satisfied, the adjustment amount: La = Lp + Ld * LKp3 / La = Ld * LKp3,

[0157] When the condition |Ld| > 3Ud is satisfied, the adjustment amount: La = Lp + 3Lud * LKp3 / La = 3Lud * LKp3,

[0158] The above settings satisfy the following setting conditions: 1Lld < 1Lud = 2Lld < 2Lud = 3Lld < 3Lud,

[0159] where La is the overall adjustment amount of the left pressure / position of the roll press, Lp is the current roll pressure / position of the left strip 1 of the roll press, LKp is the left adjustment coefficient, Lud is the upper limit of the difference between the average value of the thickness data of the left strip 1 and the target value of the product to be detected, Lld is the lower limit of the difference between the average value of the thickness data of the left strip 1 and the target value of the product to be detected. Specifically, the calculation method of the multi-step coefficient is from 1 to n steps. In this embodiment, 1Lld, 1Lud, 2Lld, 2Lud, 3Lld, and 3Lud are only for illustrative purposes, used to distinguish the upper and lower limits of the difference between the weighted average of the thickness data and the target value. Their specific values and the specific values of LKp1, LKp2, and LKp3 are obtained through experiments or experience. When the difference Ld between the weighted average of the thickness data of the left strip 1 and the target value is in different regions, different formulas are used to calculate the adjustment amount of the left pressure / position of the roll press;

[0160] The LKp adjustment coefficient specifically refers to the coefficient for converting thickness data into the pressure / position of the roller press. For example, when the pressure is increased by 1 and the thickness increases by 2, then Kp = 1 / 2 = 0.5. In short, it can be considered how much the roller press pressure / position changes corresponding to a change in thickness of 1. Its specific value can be obtained through experiments or experience;

[0161] The calculation method of the multi-step coefficient of the pressure / position adjustment amount on the right side of the roller press is specifically as follows:

[0162] Calculate the weighted average of the thickness of the nth time of the second strip on the right side:

[0163] Av = (Av1 + Av2 + … + Avn) / Wtn,

[0164] where Av is the weighted average of the thickness data of the second strip, Wtn is the number of times of weighted average n times, and Wt ≥ 1, which is used to control the number of times of superposition and averaging of the average value Av data of parameter adjustment. Av1, Av2, Av3…Avn are the average values of the thickness data of the second strip on the right side measured by the thickness gauge n times. Its specific calculation method is the same as the above density data calculation method;

[0165] Then calculate the difference Rd = Tv - Av between the weighted average of the thickness data of the second strip on the right side and the target value,

[0166] where Tv is the target value of the product thickness, and Rd is the difference between the weighted average of the thickness data of the second strip on the right side and the target value;

[0167] When it satisfies: |Rd| < 1Rld, the adjustment amount: Ra = Rp + Rd*0 / Ra = Rd*0,

[0168] When it satisfies: 1Rld ≤ |Rd| < 1Rud, the adjustment amount: Ra = Rp + Rd*RKp1 / Ra = Rd*RKp1,

[0169] When it satisfies: 2Rld ≤ |Rd| < 2Rud, the adjustment amount: Ra = Rp + Rd*RKp2 / Ra = Rd*RKp2,

[0170] When it satisfies: 3Rld ≤ |Rd| < 3Rud, the adjustment amount: Ra = Rp + Rd*RKp3 / Ra = Rd*RKp3,

[0171] When it satisfies: |Rd| > 3Ud, the adjustment amount: Ra = Rp + 3Rud*RKp3 / Ra = 3Rud*RKp3,

[0172] The above settings satisfy this setting condition: 1Rld < 1Rud = 2Rld < 2Rud = 3Rld < 3Rud;

[0173] Among them, Ra is the overall adjustment amount of the pressure / position on the right side of the roll press, Rp is the current roll pressure / position of the second strip on the right side of the roll press, RKp is the adjustment coefficient on the right side, Rud is the upper limit of the difference between the average value of the thickness data of the second strip on the right side and the target value of the product to be detected, Rld is the lower limit of the difference between the average value of the thickness data of the second strip on the right side and the target value of the product to be detected. Similarly, 1Rld, 1Rud, 2Rld, 2Rud, 3Rld, 3Rud, RKp1, RKp2, and RKp3 are only for illustrative purposes, and their specific values are obtained through experiments or experience. When the difference Rd between the weighted average value of the thickness data of the second strip on the right side and the target value is in different regions, different formulas are used to calculate the adjustment amount of the pressure / position on the right side of the roll press;

[0174] The RKp adjustment coefficient specifically refers to the coefficient that converts thickness to the pressure / position of the roll press. For example: when the pressure increases by 1 and the thickness increases by 2, then Kp = 1 / 2 = 0.5. In short, it can be considered how much the pressure / position of the roll press changes corresponding to a change in the thickness by 1. Its specific value can be obtained through experiments or experience;

[0175] The calculation method of the adjustment amount of the pressure / position on the left and right sides of the roll press can also be PID adjustment calculation:

[0176]

[0177] Original + adjustment amount adjustment: u t = u t-1 + Δu t ,

[0178] Adjustment amount adjustment: u t = Δu t ,

[0179] ΔP t = u t ,

[0180] P t = P t-1 + ΔP t ,

[0181] Among them, Δu t is the output increment of the PID controller,

[0182] Kp: adjustment coefficient,

[0183] e t : The error between the target value and the actual value of the thickness data at this moment,

[0184] e t-1 : The error between the target value and the actual value of the thickness data at the previous moment,

[0185] e t-2: The error between the target value and the actual value of the thickness data at the current moment for the previous two times,

[0186] Ti: The integral time constant,

[0187] T d : The differential time constant,

[0188] u t : The output of the PID controller,

[0189] ΔP t : The output increment at time t,

[0190] P t : The roll position output at time t.

[0191] The adjustment of the pressure / position on both axial sides of the roll press also includes speed closed-loop adjustment. Using the default closed-loop, the pole piece is adjusted to a certain thickness range, that is, the coating machine pressure / pump speed closed-loop adjustment, the roll press pressure / position closed-loop adjustment, and logical judgment is performed according to the collected equipment parameters. The speed closed-loop adjustment includes:

[0192] S1: Collect the low-speed A value;

[0193] S2: After collecting the A value, collect the high-speed B value;

[0194] S3: Calculate the roll press pressure / position compensation amount.

[0195] Collecting the low-speed A value includes the following steps:

[0196] S11: When Ld2 - Lt ≤ LYs ≤ Ld2 + Lt and |D| ≤ Df, collect the A value. When LYs < Ld2 - Lt, Ys > Ld2 + Lt or |D| > Df, do not collect the A value;

[0197] S12: When the conditions of S11 are met, multiple A values will be continuously collected, and the last A value is taken as the final value. Specifically, during operation, the speed of the roll press and the product thickness will be continuously collected for the judgment of S11. Therefore, there will be many A values that meet the conditions. Taking the last A value as the final value is because the last A value is the most stable;

[0198] Among them, LYs is the low-speed running speed of the roll press, Ld2 is the speed target value for collecting A data at low speed, Lt is the fluctuation range of the target speed when collecting A at low speed, D is the difference between the product thickness target value and the measured value, and Df is the allowable fluctuation range of the difference between the product thickness target value and the measured value. During actual operation, both Ld2 and Lt are set by the staff.

[0199] Collecting the high-speed B value includes the following steps:

[0200] S21: When Hd2 - Ht ≤ HYs ≤ Hd2 + Ht and |D| ≤ Df, collect the B value; when HYs < Hd2 - Ht, Ys > Hd2 + Ht or |D| > Df, do not collect the B value;

[0201] S22: When the conditions of S21 are met, only take the first B value as the final value. Specifically, during operation, the speed of the roller press is gradually increased under manual or equipment control, and the first B value is taken as the final value;

[0202] Among them, HYs is the high-speed operating speed of the roller press, Hd2 is the speed target value for collecting B data at high speed, Ht is the fluctuation range of the target speed when collecting B at high speed, D is the difference between the target value and the measured value of the product thickness, Df is the allowable fluctuation range of the difference between the target value and the measured value of the product thickness. During actual operation, both Hd2 and Ht are set by the staff;

[0203] The calculation formula for the pressure / position compensation amount on both sides of the roller press is any one of the following:

[0204] (1) Multi-step coefficient calculation method:

[0205] nLa = T * Kp(2n - 1);

[0206] nHa = T * Kp2n;

[0207] T = B - A;

[0208] Kp1 + Kp2 + Kp3 + …… + Kpn = 1;

[0209] Among them, nLa is the pressure / position adjustment amount of the roller press at the nth low speed, nHa is the pressure / position adjustment amount of the roller press at the nth high speed, Kpn is the adjustment coefficient of the nth order. Specifically, it can be considered how much the pressure / position of the roller press changes corresponding to a speed change. Kp1, Kp2, Kp3 …… Kpn are only used for distinction, and their specific values can be obtained according to experience or tests;

[0210] The specific calculation method is as follows:

[0211] 1st order adjustment:

[0212] Low-speed adjustment: 1La = T * Kp1,

[0213] High-speed adjustment: 1Ha = T * Kp2;

[0214] 2nd order adjustment:

[0215] Low-speed adjustment: 1La = T * Kp3,

[0216] High-speed adjustment: 1Ha = T * Kp4;

[0217] 3rd order adjustment:

[0218] Low-speed regulation: 1La = T * Kp5,

[0219] High-speed regulation: 1Ha = T * Kp6;

[0220] ......

[0221] Nth-order regulation:

[0222] Low-speed regulation: nLa = T * Kp(2n - 1),

[0223] High-speed regulation: nHa = T * Kp2n;

[0224] (2) PID regulation calculation:

[0225]

[0226] Original + adjustment amount regulation: u t = u t-1 + Δu t ,

[0227] Adjustment amount regulation: u t = Δu t ,

[0228] ΔP t = u t ,

[0229] P t = P t-1 + ΔP t ,

[0230] Among them, Δu t is the output increment of the PID controller,

[0231] Kp: Regulation coefficient,

[0232] e t : The error between the B value and the A value at the current moment,

[0233] e t-1 : The error between the previous B value and the A value at the current moment,

[0234] e t-2 : The error between the two previous B values and the A value at the current moment,

[0235] Ti: Integral time constant,

[0236] T d : Differential time constant,

[0237] u t : Output of the PID controller,

[0238] ΔP t : The output increment at time t,

[0239] tP t : The roller position output at time t.

[0240] In summary, the pressure / pump speed of the coater is adjusted using the real-time surface density data of the product. After adjustment, the coater controls the surface density of the product in reverse, making the surface density of the product approach the target value. The pressure / position on both sides of the roller press is adjusted in real time using the real-time thickness on both sides of the product. After adjustment, the roller press controls the thickness on both sides of the product in reverse, making the thickness on both sides of the product approach the target value. Based on the default closed-loop, the speed closed-loop corrects the pressure / position parameters of the roller press during acceleration and deceleration by collecting parameters such as the average strip thickness on both sides of the roller-pressed electrode, the real-time pressure / position on both sides of the main roller of the roller press, and the speed of the roller press in real time, so as to achieve real-time correction of the thickness on both sides to the set target value range. The default closed-loop and the speed closed-loop can improve the stability of the coating / roller pressing equipment and the quality of the products to be detected by controlling or correcting the parameters of the coating / roller pressing equipment in real time, and reduce the product rejection rate.

[0241] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

Claims

1. A coating and rolling closed-loop adjustment method, characterized in that, It includes the following steps: Closed-loop switch control for determining whether to enable closed-loop regulation; Closed-loop regulation of the coating machine pressure / pump speed; Closed-loop regulation of the roll press pressure / position; The closed-loop switch control includes the following steps: Web running speed limit: A speed limit threshold Yl is set. If the web running speed Ys < Yl, adjustment can be performed; otherwise, it cannot be performed. Distance Dt between the control point and the detection device: When the web running length Yp at the current scanning position and the equal-length roll ≥ Yp + Dt, adjustment can be performed; otherwise, adjustment cannot be performed. Adjustment period Rp: The surface density meter or thickness gauge scans Rp times for closed-loop regulation once. Speed fluctuation detection: When Ysv - Ys ≤ D, it indicates a constant speed and adjustment can be performed; When Ysv - Ys > D, it indicates a non-constant speed and adjustment cannot be performed; Where Ys is the current speed value, Ysv is the average value of the previous N speed values, the acquisition time interval is S, and D is the speed fluctuation range. The closed-loop regulation of the coating machine pressure / pump speed and the closed-loop regulation of the roll press pressure / position both include the following steps: Scanning the product to be detected by the detection device to obtain scanning data; Calculating the adjustment amount of the coating machine pressure / pump speed or the roll press pressure / position according to the scanning data; The calculation method for calculating the adjustment amount of the coating machine pressure / pump speed or the roll press pressure / position is PID adjustment calculation: Original + adjustment amount adjustment: u t = u t-1 + Δu t , Adjustment amount adjustment: u t = Δu t , ΔP t = u t , P t = P t-1 + ΔP t , where Δu t is the output increment of the PID controller, Kp: Adjustment coefficient, e t : The error between the target value and the actual value of the detected data at the current moment e t-1 : Error between the previous target value and the actual value of the detection data at the current moment e t-2 : The error between the target value and the actual value of the detection data in the previous two times at the current moment Ti: Integral time constant, T d : is the differential time constant, u t : The output of the PID controller, ΔP t : Output increment at time t, P t : The roll position output at time t.

2. The coating and rolling closed-loop adjustment method according to claim 1, wherein The calculation method for calculating the adjustment amount of the coating machine pressure / pump speed and the pressures / positions on both axial sides of the roll press is the multi-step coefficient calculation method: Calculating the weighted average value of the nth scanning data: Av = (Av1 + Av2 + … + Avn) / Wtn, Where Av is the weighted average value of the scanning data, Wtn is the number of weighted average times n times, and Wt ≥ 1, which is used to control the average number of data superposition and averaging of the parameter adjustment average value Av. Av1, Av2, Av3…Avn are the average values of the detection device's n scanning data. Calculating the difference between the weighted average value of the scanning data and the target value: Dv = Tv - Av, Where Tv is the target value corresponding to the product scanning data, and Dv is the difference between the weighted average value of the scanning data and the target value. When it satisfies: |Dv| < Ld1, the adjustment amount: Aa = Cp + Dv * 0 or Aa = Dv * 0, When it satisfies: Ld1 ≤ |Dv| < Ud, the adjustment amount: Aa = Cp + Dv * Kp or Aa = Dv * Kp, When it satisfies: |Dv| > Ud, the adjustment amount: Aa = Cp + Ud * Kp or Aa = Ud * Kp, Where Aa is the overall adjustment amount of the device, Cp is the current parameter of the device, Kp is the adjustment coefficient, Ud is the upper limit of the difference between the average value of the scanning data and the target value of the product to be detected, Ld is the lower limit of the difference between the average value of the scanning data and the target value of the product to be detected, Ld1~Ud is a single range or a continuous multiple range value, and Kp is different when Dv is in different ranges.

3. A coating and rolling closed-loop adjustment method according to claim 2, characterized in that Aa is the pressure / pump speed adjustment amount of the coater screw pump, Cp is the current pressure / pump speed of the coater screw pump, the detection device is a surface density meter, the scanned data is the surface density of the product to be detected, Av is the average surface density, Tv is the target surface density value, and Dv is the difference between the average surface density and the target value.

4. A coating and rolling closed-loop adjustment method according to claim 2, characterized in that Aa is the pressure / position adjustment amount of the roll press, Cp is the current pressure / position of the roll press, the detection device is a thickness gauge, the scanned data is the split thickness of the left and right sides of the product to be roll-pressed, there are two groups of Av, and the two Avs are respectively the average values of the split thickness of the left and right sides of the product to be detected, Tv is the target thickness value of the product to be detected, Dv is the difference between the average thickness and the target value, and the pressure / position adjustment amounts on the left and right sides of the axial direction of the roll press are calculated respectively.

5. A coating and rolling closed-loop adjustment method according to claim 4, characterized in that The adjustment of the pressure / position on both sides of the axial direction of the roll press also includes speed closed-loop adjustment, and the speed closed-loop adjustment includes: S1: Collect the low-speed A value; S2: After collecting the A value, collect the high-speed B value; S3: Calculate the pressure / position compensation amount of the roll press.

6. According to the coating and roll pressing closed-loop adjustment method described in claim 5, characterized in that Collecting the low-speed A value includes the following steps: S11: When Ld2 - Lt ≤ LYs ≤ Ld2 + Lt and |D| ≤ Df, collect the A value. When LYs < Ld2 - Lt, Ys > Ld2 + Lt or |D| > Df, do not collect the A value; S12: When the conditions of S11 are met, multiple A values will be continuously collected, and the last A value is taken as the final value; Among them, LYs is the low-speed running speed of the roll press, Ld2 is the speed target value for collecting A data at low speed, Lt is the fluctuation range of the target speed when collecting A at low speed, D is the difference between the target product thickness value and the measured value, and Df is the allowable fluctuation range of the difference between the target product thickness value and the measured value; Collecting the high-speed B value includes the following steps: S21: When Hd2 - Ht ≤ HYs ≤ Hd2 + Ht and |D| ≤ Df, collect the B value. When HYs < Hd2 - Ht, Ys > Hd2 + Ht or |D| > Df, do not collect the B value; S22: When the conditions of S21 are met, only the first B value is taken as the final value; Among them, HYs is the high-speed running speed of the roll press, Hd2 is the speed target value for collecting B data at high speed, Ht is the fluctuation range of the target speed when collecting B at high speed, D is the difference between the target product thickness value and the measured value, and Df is the allowable fluctuation range of the difference between the target product thickness value and the measured value.

7. A coating and rolling closed-loop adjustment method according to claim 5, characterized in that, The calculation formula for the pressure / position compensation amount on both sides of the roll press is a multi-step coefficient calculation method: nLa = T * Kp(2n - 1); nHa = T * Kp2n; T = B - A; Kp1 + Kp2 + Kp3 + …… + Kpn = 1; Among them, nLa is the pressure / position adjustment amount of the roll press at the nth low speed, nHa is the pressure / position adjustment amount of the roll press at the nth high speed, and Kpn is the adjustment coefficient of the nth order.

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