Feedforward control method, feedforward controller and tension control system

Abstract

The embodiment of the present application provides a feedforward control method, a feedforward controller and a tension control system. The feedforward control method comprises the following steps: obtaining a current material belt tension value detected by a tension detection unit; calculating a corresponding feedforward controller analog channel output value according to a relationship model between a feedforward controller analog channel output value and the material belt tension value and the obtained current material belt tension value; and outputting a corresponding analog signal to a power mechanism according to the calculated feedforward controller analog channel output value to pre-control the tension of the material belt by controlling the output of the power mechanism. The pre-control relationship model is accurate, the proportion of the output of the tension PID in the whole output is small, so that a higher proportional coefficient can be used, and the tension response speed and the control precision are improved.

Description

Technical Field

[0001] This invention relates to the field of tension control technology, and in particular to a feedforward control method, a feedforward controller, and a tension control system. Background Technology

[0002] With the development of the new energy industry, the demand for lithium batteries is increasing, and the requirements for lithium battery production lines are also becoming more stringent. As a piece of equipment in the lithium battery production process, the electrode rolling mill plays a crucial role in battery production. The tension control mechanism, as an important component of the electrode rolling mill (such as...), Figure 1 The requirements for tension control in the electrode mill (as shown) are also higher. The tension control requirements for the electrode mill are as follows: 1. The tension fluctuation should be small, and the actual tension value should match the set value; 2. When adjusting the tension during operation, the tension should not be over-adjusted; 3. Solve the problem of excessive tension value deviation after two years of operation.

[0003] Tension control primarily involves first providing the cylinder controller with an initial value as the pre-control pressure based on a setpoint, generating a certain tension. Then, the difference between the feedback tension and the setpoint tension is used for PID calculations. Currently, the pre-control pressure value is obtained as follows: 1. Based on the given cylinder pressure value P and the cylinder bore D, calculate the cylinder output force. 2. Based on the lever arms L1 and L2 of the dancing roller, we can derive... 3. The tension F in the material is derived from the angle α between the electrode and the roller. 21 =F2cosα; 4. Therefore, different set tensions F can be deduced. 21 The following is used to specify the pre-controlled air pressure value. Then, the value of the analog quantity for the given control is obtained based on the U / P relationship.

[0004] However, due to manufacturing errors and assembly issues, connection points (e.g.) Figure 1 The frictional changes in a, b, and c) cannot be calculated. Therefore, the relationship between tension and air pressure obtained by existing methods is also inaccurate. Inaccurate relationships can lead to instability and inaccuracy in tension control, and in severe cases, can cause belt breakage and affect production. Summary of the Invention

[0005] In view of this, the present invention provides a feedforward control method, a feedforward controller, and a tension control system to at least partially solve the above-mentioned technical problems.

[0006] A first aspect of the present invention provides a feedforward control method for a tension control system of an interval tension mechanism, the feedforward control method comprising:

[0007] A. Obtain the current tension value of the material band detected by the tension detection unit;

[0008] B calculates the corresponding output value of the feedforward controller analog channel based on the relationship model between the output value of the feedforward controller analog channel and the material strip tension value, and the obtained current material strip tension value.

[0009] C outputs a corresponding analog signal to the power mechanism based on the calculated output value of the feedforward controller analog channel to control the output force of the power mechanism in order to pre-control the tension of the material strip.

[0010] In one possible implementation, before step A, the following is also included:

[0011] D. Establish a relationship model between the analog output value of the feedforward controller and the tension value of the material band. The relationship model is a linear relationship model.

[0012] In one possible implementation, step D is preceded by:

[0013] E controls the first main shaft of the interval tension mechanism to be stationary and the second main shaft to rotate clockwise at low speed until the material belt overcomes the output force of the power mechanism and stops when the dancing roller arm in the power mechanism is parallel to the ground. The state at which this stops is the tension establishment state of the material belt.

[0014] In one possible implementation, step D further includes:

[0015] When the material band tension is established, record the output value of the analog channel of the feedforward controller and the material band tension value detected by the tension detection unit when the feedforward controller gives N different analog signals to the power mechanism, and obtain N sets of data corresponding to N fitting points;

[0016] A preset curve fitting algorithm is used to perform linear fitting on the N sets of data to obtain the linear relationship model between the output value of the analog channel of the feedforward controller and the tension value of the material band. The preset curve fitting algorithm is the least squares method, the gradient descent method, or the Gauss-Newton-Leimas algorithm.

[0017] In one possible implementation, the feedforward control method further includes:

[0018] Steps E, D, and A through C are executed sequentially in a timed manner; or, in response to a control command, steps E, D, A through C are executed sequentially.

[0019] In one possible implementation, the feedforward control method further includes:

[0020] In the tension PID control stage following the pre-control, steps A to C are executed in response to changes in the acquired material belt tension value.

[0021] A second aspect of the present invention also provides a feedforward controller for feedforward control of a tension control system for an interval tension mechanism, the feedforward controller comprising:

[0022] The acquisition module is used to acquire the current tension value of the material band detected by the tension detection unit;

[0023] The calculation module calculates the corresponding output value of the feedforward controller analog channel based on the relationship model between the output value of the feedforward controller analog channel and the material belt tension value and the obtained current material belt tension value.

[0024] The output module is used to output a corresponding analog signal to the power mechanism based on the calculated output value of the feedforward controller analog channel, so as to control the output force of the power mechanism to pre-control the tension of the material strip.

[0025] In one possible implementation, the feedforward controller further includes a model building module. The model building module is further used to record the output values ​​of the feedforward controller analog channel and the material band tension value detected by the tension detection unit when the feedforward controller gives N different analog signals to the power mechanism under the material tension establishment state, so as to obtain N sets of data corresponding to N fitting points. The module then uses a preset linear fitting algorithm to fit the N sets of data to obtain a linear relationship model between the output values ​​of the feedforward controller analog channel and the material band tension value. The preset linear fitting algorithm is the least squares method, gradient descent method, or Gauss-Newton-Leamaz algorithm.

[0026] In one possible implementation, the feedforward controller further includes a tension establishment module, which controls the first side main shaft of the interval tension mechanism to be stationary and the second side main shaft to rotate clockwise at low speed until the material belt overcomes the output force of the power mechanism and stops when the dancing roller arm in the power mechanism is parallel to the ground. The state at which this stops is the tension establishment state of the material belt.

[0027] A third aspect of the present invention also provides a tension control system for an interval tension mechanism, comprising:

[0028] Tension detection unit, used to detect the tension value of the material strip;

[0029] The feedforward controller according to any of the foregoing;

[0030] The PID controller is used to perform PID calculations based on the difference between the current tension value of the material belt detected by the tension detection unit and the set tension value after the feedforward controller performs pre-control, and outputs the calculation results to the power mechanism.

[0031] The power mechanism is used to control the tension of the material strip by generating an output force based on the output value of the analog quantity received from the feedforward controller and the calculation result received from the PID controller.

[0032] In the embodiments of this application, compared with the prior art, at least the following advantages are included:

[0033] (1) A new pre-control relationship model (i.e., the relationship model between the output value of the analog channel of the feedforward controller and the tension value of the material belt) is proposed. The output value of the feedforward controller calculated by the pre-control relationship model can accurately match different interval tension mechanisms, so that the output of the tension PID accounts for a small proportion of the total output, thereby allowing the use of a higher proportional coefficient to improve the tension response speed and control accuracy.

[0034] (2) The aforementioned new pre-control relationship model is obtained by experimentally obtaining the original data and then fitting it with the least squares method, which avoids the inaccuracy of the relationship caused by assembly and machining errors. Furthermore, the experimental process is repeated after the wear of the interval tension mechanism to update the pre-control relationship model, thereby ensuring the consistency and accuracy of tension control after the wear of the interval tension mechanism.

[0035] (3) The proposed new pre-control relationship model can ensure that when tension fluctuations are caused by changes in the set value during the operation of the interval tension mechanism, the feedforward control algorithm is applied so that the corresponding output air pressure value is accurately obtained at the moment the new set value is input, so that the feedback tension value is the same as the set tension, thereby eliminating the disturbance of the controlled variable in the bud and preventing the controlled variable from deviating due to the disturbance or the change of the given value. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of an example interval tension mechanism according to the present invention.

[0037] Figure 2 This is a flowchart of a feedforward control method according to an embodiment of the present invention.

[0038] Figure 3 This is a curve showing the relationship between the output value of the analog channel of the feedforward controller and the tension value of the material belt, according to an example of the present invention.

[0039] Figure 4 This is a schematic diagram of the feedforward controller according to an embodiment of the present invention.

[0040] Figure 5 This is a schematic diagram of the tension control system for an interval tension mechanism according to an embodiment of the present invention.

[0041] List of reference numerals in the attached diagram:

[0042] First side main shaft 101

[0043] First rubber roller 102

[0044] Second side main shaft 103

[0045] Second rubber roller 104

[0046] First driven roller 105

[0047] Second driven roller 106

[0048] Tension sensor 107

[0049] Dancing Roller 108

[0050] Cylinder 109

[0051] Connections a, b, c

[0052] Feedforward Controller 400

[0053] Tension Establishment Module 401

[0054] Model building module 402

[0055] Get module 403

[0056] Calculation module 404

[0057] Output module 405

[0058] First calling module 406

[0059] Second calling module 407

[0060] Tension detection unit 501

[0061] PID controller 502

[0062] Power mechanism 503

[0063] Set tension value d Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. All other technical solutions obtained by those skilled in the art based on the embodiments of this application fall within the scope of protection of this application.

[0065] Terminology Explanation: The "interval tension mechanism" mentioned in this invention refers to a mechanism that uses two drive shafts on both sides of the interval and rubber rollers on the shafts to separate the tension of the material belt before and after movement, such as, but not limited to, the following. Figure 1 The structure shown.

[0066] Figure 2 An embodiment of the present invention, a feedforward control method, is illustrated for feedforward control of a tension control system for an interval tension mechanism. For example... Figure 2 As shown, the feedforward control method includes:

[0067] S206: Obtain the current tension value of the material band detected by the tension detection unit;

[0068] S208: The corresponding output value of the feedforward controller analog channel is calculated based on the relationship model between the output value of the feedforward controller analog channel and the material strip tension value and the obtained current material strip tension value;

[0069] S2010: Based on the calculated output value of the feedforward controller analog channel, output the corresponding analog signal to the power mechanism to control the output force of the power mechanism and pre-control the tension of the material strip.

[0070] Optionally, before step S206, step S204 is also included, namely: establishing a relationship model between the output value of the analog channel of the feedforward controller and the tension value of the material belt, wherein the relationship model is preferably a linear relationship model.

[0071] Furthermore, step S202 is included before step S204, namely: the first main shaft of the control interval tension mechanism is stationary while the second main shaft rotates clockwise at low speed until the material belt overcomes the output force of the power mechanism and is taut, and the dancing roller arm in the power mechanism is parallel to the ground, at which point it stops. The state at which this stops is the state in which the material belt tension is established. This step can be mechanically automatic or manually controlled.

[0072] Furthermore, step S204 can further include the following sub-steps: S204a, under the material tension establishment state, record the corresponding analog output values ​​of the feedforward controller and the material tension values ​​detected by the tension detection unit when the feedforward controller gives N different analog signals to the power mechanism, obtaining N sets of data corresponding to N fitting points; S204b, use a preset curve fitting algorithm to perform linear fitting on the N sets of data to obtain a linear relationship model between the analog output value of the feedforward controller and the material tension value. In step S204b, the "preset curve fitting algorithm" is preferably a linear fitting algorithm, such as, but not limited to, least squares method, gradient descent method, Gauss-Newton-Lehman algorithm, etc. Here, multiple sets of data between the air pressure value and the generated tension are found experimentally, and then a relationship model that can be used for PLC control is obtained by fitting curves, which can accurately find the cylinder air pressure value required for tension pre-control of the battery electrode roller press. This makes the output of the tension PID account for a very small proportion of the total output, thereby allowing the use of a higher proportional coefficient to improve the tension response speed and control accuracy.

[0073] Optionally, the feedforward control method further includes: executing steps S202 to S210 sequentially at timed intervals. For example, steps S202 to S210 can be re-executed every N days, N months, or N years, where N can be set as needed. This allows for the experimental acquisition of a new pre-control relationship model between the analog output value of the feedforward controller and the tension value of the material belt after the equipment reaches a certain wear level, thereby ensuring the consistency and accuracy of tension control after equipment wear.

[0074] Optionally, the feedforward control method further includes: in response to a control command, sequentially executing steps S202 to S210. For example, a peripheral control command sending button, which an operator can press to initiate the sending of the control command. Furthermore, the present invention is not limited to a button form; other equivalent forms are all within the scope of protection of the present invention.

[0075] It is understood that the tension control process of the present invention mainly includes a tension pre-control stage and a subsequent tension control stage. The aforementioned steps are mainly used in the tension pre-control stage. Optionally, the feedforward control method further includes: in the tension control stage, in response to changes in the acquired material belt tension value, executing steps S206 to S210. This ensures that tension fluctuations caused by modifications to the setpoint during equipment operation meet requirements, so that the corresponding output air pressure value is accurately obtained at the instant the new setpoint is input, making the feedback tension value the same as the set tension. This eliminates disturbances in the controlled variable at their inception, preventing deviations in the controlled variable due to disturbances or changes in the given value.

[0076] The feedforward control method of this embodiment is particularly suitable for tension control systems with interval tension mechanisms. Furthermore, the feedforward controller described in this embodiment is, for example, but not limited to, a PLC controller.

[0077] To better illustrate the technical effects of the present invention, the following describes in detail the method for obtaining the pre-control relationship model of the present invention using a battery electrode roller press with a PLC as the feedforward controller and a cylinder as the power mechanism as an example. The technical details in this example are merely exemplary and should not be construed as limiting the scope of protection of the present invention.

[0078] For each section of the tension mechanism in the battery electrode rolling mill, firstly, maintain... Figure 1 The first side main shaft 101 in the middle tension mechanism is stationary, and then the second side main shaft 103 is rotated clockwise at a low speed until the material is taut against the gravity of the dancing roller 108 and the arm of the dancing roller 108 is parallel to the ground.

[0079] Next, assuming the analog input of cylinder 109 is a voltage signal of 0-10V, the corresponding PLC analog input channel output value is 0-27648. Then, when the given control voltage is 2V, the recorded analog input is y1 = 5530, and the return value of tension detection unit 501 is recorded as x1.

[0080] Then, the PLC analog output values ​​y2, y3, y4, y5 and the corresponding tension return values ​​x2, x3, x4, x5 were recorded for each 2V increase in the analog output voltage when the given analog voltage value was 4V, 6V, 8V, and 10V, respectively. Then, five sets of data (x1,y1), (x2,y2), (x3,y3), (x4,y4), and (x5,y5) were obtained.

[0081] Then, the x and y relationship curves of the five sets of data (x1,y1), (x2,y2), (x3,y3), (x4,y4), and (x5,y5) obtained by fitting are as follows: Figure 3 As shown, we use the least squares method to fit the equation of the line. We calculate the coefficients k and intercept b of the two linear equations according to the following formulas (1) and (2).

[0082]

[0083]

[0084] Finally, when the tension is pre-controlled, the analog output value y can be equal to the coefficient k multiplied by the tension setpoint x plus the intercept b, thus obtaining the pre-control relationship model of the tension mechanism in each interval of the battery electrode roller press.

[0085] As mentioned above, the present invention obtains raw data through experiments, and then uses a linear fitting algorithm to fit the relationship model between the output value of the 400 analog channel of the feedforward controller and the tension value of the material belt. The obtained relationship model is accurate. In particular, for tension systems with multiple interval tension mechanisms, the relationship model of each tension mechanism can be obtained separately, avoiding inaccuracies in the relationship model caused by assembly and machining errors.

[0086] To implement the feedforward control method of the above embodiments, other embodiments of the present invention also provide a feedforward controller 400, such as... Figure 4As shown, the feedforward controller 400 includes an acquisition module 403, a calculation module 404, and an output module 405. It should be noted that since the following embodiments are for implementing the aforementioned method embodiments, each module in the feedforward controller 400 is designed to implement each step of the aforementioned method. Therefore, the present invention is not limited to the following embodiments, and any device or module that can implement the above method should be included within the protection scope of the present invention. Furthermore, to save space, content identical to the aforementioned method portion is omitted here.

[0087] Specifically, the acquisition module 403 is used to acquire the current material strip tension value detected by the tension detection unit; the calculation module 404 is used to calculate the corresponding feedforward controller 400 analog channel output value based on the relationship model between the analog channel output value of the feedforward controller 400 and the material strip tension value and the acquired current material strip tension value; the output module 405 is used to output the corresponding analog signal to the power mechanism based on the calculated feedforward controller 400 analog channel output value to control the output force of the power mechanism to pre-control the tension of the material strip.

[0088] Optionally, the feedforward controller 400 further includes a model building module 402. The model building module 402 is further used to record the analog output values ​​of the feedforward controller 400 and the material tension values ​​detected by the tension detection unit when the feedforward controller 400 provides N different analog signals to the power mechanism, in order to obtain N sets of data corresponding to N fitting points. A preset curve fitting algorithm is then used to fit the N sets of data to obtain a linear relationship model between the analog output values ​​of the feedforward controller 400 and the material tension values. Preferably, the preset curve fitting algorithm is a linear fitting algorithm, such as, but not limited to, least squares method, gradient descent method, Gauss-Newton-Lehman algorithm, etc.

[0089] Optionally, the feedforward controller 400 also includes a tension establishment module 401, which controls the first side main shaft of the interval tension mechanism to be stationary and the second side main shaft to rotate clockwise at low speed until the material belt overcomes the output force of the power mechanism and stops when the dancing roller arm in the power mechanism is parallel to the ground. The state at which this stops is the tension establishment state of the material belt.

[0090] Optionally, the feedforward controller 400 further includes a first invocation module 406, which is used to sequentially invoke and execute the model building module 402, acquisition module 403, calculation module 404, and output module 405, or sequentially invoke the tension building module 401, model building module 402, acquisition module 403, calculation module 404, and output module 405, in a timed manner. For example, it can be configured to re-invoke and execute every N days, N months, or N years, where N can be set according to the system's wear cycle. In this way, after the equipment reaches its wear cycle, a new relationship model between the analog output value of the feedforward controller 400 and the tension value of the material belt can be found through experiments, thereby ensuring the consistency and accuracy of tension control after equipment wear.

[0091] Optionally, the first calling module 406 is further configured to, in response to a control command received from the peripheral control command sending button, sequentially call and execute the model building module 402, the acquisition module 403, the calculation module 404, and the output module 405, or call and execute the tension building module 401, the model building module 402, the acquisition module 403, the calculation module 404, and the output module 405.

[0092] It is understood that tension control includes a tension pre-control stage and a subsequent tension control stage. Optionally, the feedforward controller 400 also includes a second calling module 407, which is used to call and execute the acquisition module 403, the calculation module 404, and the output module 405 in response to the detection of a change in the tension value of the material belt. This ensures that tension fluctuations caused by changes in the setpoint during equipment operation meet the requirements, and that the corresponding output air pressure value is accurately obtained at the instant the new setpoint is input, so that the feedback tension value is the same as the set tension. This eliminates disturbances in the controlled variable at their inception, preventing deviations in the controlled variable due to disturbances or changes in the given value.

[0093] In addition, such as Figure 5 As shown, a tension control system for an interval tension mechanism according to an embodiment of the present invention is illustrated. The tension control system includes a tension detection unit 501 for detecting the tension value of a material strip, a feedforward controller 400 of the aforementioned embodiment, a PID controller 502, and a power mechanism 503 (e.g., but not limited to, a cylinder 109, a hydraulic cylinder, etc.).

[0094] The PID controller 502 is used to perform PID calculations based on the difference between the current tension value of the material strip detected by the tension detection unit 501 and the set tension value after the feedforward controller 400 performs pre-control, and outputs the calculation result to the power mechanism 503; the power mechanism 503 is used to generate output force to control the tension of the material strip based on the output value of the analog quantity received from the feedforward controller 400 and the calculation result received from the PID controller 502.

[0095] Optionally, the tension detection unit 501 may include, for example but not limited to, [other types of components]. Figure 1 The tension sensor 107 and its arrangement are shown. Optionally, the power mechanism 503 may be, for example, but not limited to, […]. Figure 1 The cylinder 109 and oil cylinder shown are examples of cylinders.

[0096] It should be noted that in the claims and specification of this patent, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0097] Obviously, those skilled in the art will understand that the modules or steps of the embodiments described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those presented herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the embodiments of this specification are not limited to any particular combination of hardware and software.

[0098] Although the invention has been illustrated and described with reference to certain preferred embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

[0099] The present invention has been shown and described in detail above with reference to the accompanying drawings and preferred embodiments. However, the present invention is not limited to these disclosed embodiments. Based on the above embodiments, those skilled in the art will know that more embodiments of the present invention can be obtained by combining the code review methods in the different embodiments. These embodiments are also within the protection scope of the present invention.

Claims

1. A feedforward control method for a tension control system of an interval tension mechanism, characterized in that, The feedforward control method includes: A. Obtain the current tension value of the material band detected by the tension detection unit; B calculates the corresponding output value of the feedforward controller analog channel based on the relationship model between the output value of the feedforward controller analog channel and the material strip tension value, and the obtained current material strip tension value. C outputs a corresponding analog signal to the power mechanism based on the calculated output value of the feedforward controller analog channel to control the output force of the power mechanism in order to pre-control the tension of the material strip; Before step A, the following are also included: D. Establish a relationship model between the analog output value of the feedforward controller and the tension value of the material band; further, under the established tension state of the material band, record the corresponding analog output value of the feedforward controller and the tension value of the material band detected by the tension detection unit when the feedforward controller gives N different analog signals to the power mechanism, and obtain N sets of data corresponding to N fitting points; use a preset curve fitting algorithm to perform linear fitting on the N sets of data to obtain the relationship model between the analog output value of the feedforward controller and the tension value of the material band; The relationship model is a linear relationship model.

2. The feedforward control method according to claim 1, characterized in that, The preset curve fitting algorithm is the least squares method, gradient descent method, or Gauss-Newton-Leimas algorithm.

3. The feedforward control method according to claim 2, characterized in that, Step D is preceded by: E controls the first main shaft of the interval tension mechanism to be stationary and the second main shaft to rotate clockwise at low speed until the material belt overcomes the output force of the power mechanism and stops when the dancing roller arm in the power mechanism is parallel to the ground. The state at which this stops is the tension establishment state of the material belt.

4. The feedforward control method according to claim 3, characterized in that, The feedforward control method further includes: Steps E, D, and A through C are executed sequentially in a timed manner; or, in response to a control command, steps E, D, A through C are executed sequentially.

5. The feedforward control method according to any one of claims 1-4, characterized in that, The feedforward control method further includes: In the tension control phase following the pre-control, steps A to C are executed in response to changes in the acquired material band tension value.

6. A feedforward controller for feedforward control of a tension control system for an interval tension mechanism, characterized in that, The feedforward controller (400) includes: The acquisition module (403) is used to acquire the current tension value of the material band detected by the tension detection unit; The calculation module (404) is used to calculate the corresponding output value of the analog channel of the feedforward controller (400) based on the relationship model between the output value of the analog channel of the feedforward controller (400) and the tension value of the material strip and the current tension value of the material strip obtained; The output module (405) is used to output a corresponding analog signal to the power mechanism according to the calculated analog channel output value of the feedforward controller (400) to control the output force of the power mechanism to pre-control the tension of the material strip; The feedforward controller (400) further includes a model building module (402) for establishing a relationship model between the output value of the analog channel of the feedforward controller and the tension value of the material band. Further, under the material band tension establishment state, the output value of the analog channel of the feedforward controller and the tension value of the material band detected by the tension detection unit are recorded when the feedforward controller provides N different analog signals to the power mechanism, resulting in N sets of data corresponding to N fitting points. A preset curve fitting algorithm is used to perform linear fitting on the N sets of data to obtain the relationship model between the output value of the analog channel of the feedforward controller and the tension value of the material band. The relationship model is a linear relationship model.

7. The feedforward controller (400) according to claim 6, characterized in that, The preset curve fitting algorithm is the least squares method, gradient descent method, or Gauss-Newton-Leimas algorithm.

8. The feedforward controller (400) according to claim 6, characterized in that, The feedforward controller (400) also includes a tension establishment module (401), which controls the first side main shaft (101) in the interval tension mechanism to be stationary and the second side main shaft (103) to rotate clockwise at low speed until the material belt overcomes the output force of the power mechanism (503) and stops when the dancing roller (108) arm in the power mechanism is parallel to the ground. The state at which it stops is the tension establishment state of the material belt.

9. A tension control system for an interval tension mechanism, characterized in that, include: Tension detection unit (501) is used to detect the tension value of the material strip; The feedforward controller (400) according to any one of claims 6-8; The PID controller (502) is used to perform PID calculations based on the difference between the current material belt tension value detected by the tension detection unit (501) and the set tension value after the feedforward controller (400) performs pre-control, and outputs the calculation results to the power mechanism (503). The power mechanism (503) is used to generate output force to control the tension of the material strip based on the output value of the analog quantity received from the feedforward controller (400) and the calculation result received from the PID controller (502).

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