Constant tension control method, frequency converter and readable storage medium

Abstract

The invention discloses a constant tension control method, a frequency converter and a readable storage medium, and relates to the technical field of automatic control, the constant tension control method is applied to a winding frequency converter in a dual-frequency-conversion winding and unwinding system, and the dual-frequency-conversion winding and unwinding system further comprises a traction motor and a winding motor. The constant tension control method comprises the steps that the motor linear speed of the traction motor and the tension feedback value of a tension detection area are obtained, the tension control mode of the winding frequency converter is determined, and the tension control mode comprises a winding starting control mode and an unwinding starting control mode; according to the motor linear speed, the tension feedback value and the tension control mode, the working frequency output to the winding motor by the winding frequency converter is determined; and controlling the winding motor to rotate according to the working frequency so as to generate constant tension in the dual-frequency-conversion winding and unwinding system. The problem that an existing tension control mode is low in control precision is solved.

Description

Technical Field

[0001] The present application relates to the field of automation control technology, and in particular to a constant tension control method, a frequency converter and a readable storage medium. Background Art

[0002] The tension control device is a device that realizes constant tension control or taper tension control. At present, in order to improve the tension control accuracy of the tension control device, PLC (Programmable Logic Controller) is usually used as the tension control device, so that the corresponding operation instructions are transmitted to the inverter through the PLC, and then the inverter drives the motor to maintain constant tension.

[0003] However, the PLC needs to pass through a large number of hardware when transmitting the operation instruction (the operation instruction carries the operating frequency that the inverter needs to output to the motor) to the inverter. As a result, due to the influence of transmission delay, the inverter will not be able to respond to the operation instruction in time, that is, there is a response delay between the PLC and the inverter. The existence of response delay will cause the motor to have too little or too much adjustment force, which will make it difficult to accurately control the tension. Therefore, the control accuracy of the existing tension control method is low. Summary of the invention

[0004] The main purpose of the present application is to provide a constant tension control method, device, frequency converter and readable storage medium, aiming to solve the technical problem of low control accuracy of the existing tension control method.

[0005] To achieve the above object, the present application provides a constant tension control method, which is applied to a winding frequency converter in a dual-frequency winding and unwinding system, wherein the dual-frequency winding and unwinding system further includes a traction motor and a winding motor, and the constant tension control method includes:

[0006] Acquire the motor linear speed of the traction motor and the tension feedback value of the tension detection area, and determine the tension control mode of the winding inverter, wherein the tension control mode includes a winding start control mode and an unwinding start control mode;

[0007] Determine the operating frequency output by the winding inverter to the winding motor according to the motor linear speed, the tension feedback value and the tension control mode;

[0008] According to the working frequency, the winding motor is controlled to rotate so as to generate a constant tension in the dual-frequency variable winding and unwinding system.

[0009] Optionally, the step of determining the operating frequency output by the winding inverter to the winding motor according to the motor linear speed, the tension feedback value and the tension control mode includes:

[0010] Determining a tension value interval in which the tension feedback value is located according to the motor linear speed and the tension control mode;

[0011] Determine the operating frequency of the winding frequency converter output to the winding motor corresponding to the tension value range.

[0012] Optionally, when the tension control mode is a winding start control mode, the step of determining the operating frequency outputted to the winding motor by the winding frequency converter corresponding to the tension value interval includes:

[0013] Obtaining the actual frequency outputted from the winding frequency converter to the winding motor;

[0014] If it is verified that the motor linear speed is less than or equal to the first preset linear speed threshold, or if it is verified that the motor linear speed is greater than or equal to the second preset linear speed threshold, a first tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed is determined;

[0015] If the tension feedback value is less than the first tension difference value, the sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor;

[0016] If the tension feedback value is greater than or equal to the first tension difference value, a first tension frequency corresponding to the tension feedback value is obtained, and a first target frequency of the winding frequency converter is determined according to the motor linear speed;

[0017] The sum of the first tension frequency and the first target frequency is used as the operating frequency output by the winding inverter to the winding motor.

[0018] Optionally, the step of obtaining a first tension frequency corresponding to the tension feedback value and determining a first target frequency of the winding frequency converter according to the motor linear speed includes:

[0019] According to the tension feedback value and the motor linear speed, a first tension frequency corresponding to the tension feedback value is calculated by a PID algorithm;

[0020] Calculate the first winding diameter according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the operating frequency of the winding motor;

[0021] According to the motor linear speed and the first coil diameter, a second coil diameter is calculated by a PID algorithm;

[0022] The first target frequency of the winding inverter is calculated according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the second winding diameter.

[0023] Optionally, the constant tension control method further comprises:

[0024] If it is verified that the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold, then obtaining the motor linear speed of the traction motor at the next time step;

[0025] If the motor linear speed at the next time step is within the linear speed range corresponding to the first preset linear speed threshold, or within the linear speed range corresponding to the second preset linear speed threshold, the operating frequency output by the winding inverter to the winding motor is maintained at the actual frequency.

[0026] Optionally, when the tension control mode is the unwinding start control mode, the step of determining the operating frequency outputted to the winding motor by the winding frequency converter corresponding to the tension value interval includes:

[0027] Obtaining the actual frequency of the winding frequency converter;

[0028] If it is verified that the tension feedback value is greater than the preset tension given threshold, then verify whether the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold;

[0029] If it is verified that the motor linear speed is less than or equal to the first preset linear speed threshold, or if it is verified that the motor linear speed is greater than or equal to the second preset linear speed threshold, then determining the tension and value of the tension switching value corresponding to the preset tension given threshold and the motor linear speed;

[0030] If the tension feedback value is greater than the tension sum value, the sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor;

[0031] If the tension feedback value is less than or equal to the tension sum value, a second tension frequency corresponding to the tension feedback value is obtained, and a second target frequency of the winding frequency converter is determined according to the motor linear speed;

[0032] The sum of the second tension frequency and the second target frequency is used as the operating frequency output by the winding inverter to the winding motor.

[0033] Optionally, the constant tension control method further comprises:

[0034] If it is verified that the tension feedback value is less than or equal to the preset tension given threshold, a second tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed is determined;

[0035] If the tension feedback value is less than the second tension difference value, the preset reverse cutoff frequency is used as the operating frequency outputted from the winding frequency converter to the winding motor;

[0036] If the tension feedback value is greater than or equal to the second tension difference value, a third tension frequency corresponding to the tension feedback value is obtained, and a third target frequency of the winding inverter is determined according to the motor linear speed;

[0037] The sum of the third tension frequency and the third target frequency is used as the operating frequency output by the winding inverter to the winding motor.

[0038] Optionally, the dual-frequency reeling and unreeling system further includes a reeling disk, and after the step of controlling the rotation of the reeling motor according to the working frequency, the constant tension control method further includes:

[0039] If it is verified that the winding reel in the storage state is in a full reel state, the actual frequency output by the winding inverter to the winding motor is obtained, and the reel-changing pre-driving frequency corresponding to the actual frequency is calculated;

[0040] The working frequency outputted from the winding frequency converter to the winding motor is adjusted to the roll-changing pre-driving frequency, so as to control the winding motor to switch to the winding reel in an empty reel state for winding.

[0041] Optionally, the constant tension control method further comprises:

[0042] When the motor linear speed is greater than a third preset linear speed threshold, the traction motor and the winding motor are controlled to stop rotating, wherein the third preset linear speed threshold is greater than the second preset linear speed threshold.

[0043] The present application also provides a constant tension control device, which is applied to a winding frequency converter in a dual-frequency winding and unwinding system, wherein the dual-frequency winding and unwinding system further includes a traction motor and a winding motor, and the constant tension control device includes:

[0044] An acquisition module, used to acquire the motor linear speed of the traction motor and the tension feedback value of the tension detection area, and determine the tension control mode of the winding inverter, wherein the tension control mode includes a winding start control mode and an unwinding start control mode;

[0045] A determination module, used for determining the operating frequency outputted from the winding inverter to the winding motor according to the motor linear speed, the tension feedback value and the tension control mode;

[0046] The control module is used to control the rotation of the winding motor according to the working frequency to generate a constant tension in the dual-frequency conversion winding and unwinding system.

[0047] The present application also provides a frequency converter, which is a physical device, and includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the steps of the constant tension control method as described above.

[0048] The present application also provides a readable storage medium, which is a computer-readable storage medium. A program for implementing the constant tension control method is stored on the computer-readable storage medium. The program for implementing the constant tension control method is executed by a processor to implement the steps of the constant tension control method as described above.

[0049] The present application also provides a computer program product, including a computer program, wherein when the computer program is executed by a processor, the steps of the constant tension control method as described above are implemented.

[0050] The present application provides a constant tension control method, which is applied to a winding inverter in a dual-frequency winding and unwinding system. The dual-frequency winding and unwinding system also includes a traction motor and a winding motor. The present application first obtains the motor line speed of the traction motor and the tension feedback value of the tension detection area, and determines the tension control mode of the winding inverter, which includes a winding start control mode and an unwinding start control mode; then, according to the motor line speed, the tension feedback value and the tension control mode, the operating frequency of the winding inverter output to the winding motor is determined; finally, according to the operating frequency, the winding motor is controlled to rotate to generate a constant tension in the dual-frequency winding and unwinding system.

[0051] The present application directly determines the operating frequency required to be output to the winding motor in the winding frequency converter, so as to control the rotation of the winding motor through the determined operating frequency, and then generate a constant tension in the dual-frequency winding and unwinding system through the rotation of the winding motor, thereby eliminating the need to use other equipment to determine the required operating frequency of the winding frequency converter, overcoming the technical defect that the winding frequency converter needs to wait until it receives the operating frequency transmitted by other equipment before controlling the motor to rotate at the corresponding frequency, solving the technical problem of low control accuracy of the existing tension control method, and improving the tension control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0053] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0054] Figure 1 A schematic diagram of the structure of a dual-frequency rewinding and unwinding system provided in Example 1 of the present application;

[0055] Figure 2 A flow chart of the first embodiment of the constant tension control method of the present application;

[0056] Figure 3 A schematic diagram of wires in different coil diameters provided in Example 1 of the present application;

[0057] Figure 4 A flow chart of the second embodiment of the constant tension control method of the present application;

[0058] Figure 5 A brief flow chart of a constant tension control method is provided for the second embodiment of the present application;

[0059] Figure 6 This is a schematic diagram of the module structure of the constant tension control device of an embodiment of the present application;

[0060] Figure 7 Schematic diagram of the device structure of the hardware operating environment involved in the constant tension control method in the embodiment of the present application.

[0061] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0062] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work belong to the scope of protection of the present invention.

[0063] Embodiment 1

[0064] The tension control device is a device that realizes constant tension control or taper tension control. At present, in order to improve the tension control accuracy of the tension control device, PLC is usually used as the tension control device to transmit the corresponding operation instructions to the inverter through the PLC, and then the inverter drives the motor to maintain constant tension.

[0065] However, the PLC needs to pass through a large number of hardware when transmitting the operation instruction (the operation instruction carries the operating frequency that the inverter needs to output to the motor) to the inverter. As a result, due to the influence of transmission delay, the inverter will not be able to respond to the operation instruction in time, that is, there is a response delay between the PLC and the inverter. The existence of response delay will cause the motor to have too little or too much adjustment force, which will make it difficult to accurately control the tension. Therefore, the control accuracy of the existing tension control method is low.

[0066] As an example, see Figure 1 , Figure 1 A structural schematic diagram of a dual-frequency winding and unwinding system is provided, and the dual-frequency winding and unwinding system may include a traction inverter P1, a winding inverter P2, a traction motor M1, a winding motor M2, a tension movable pulley Q1, a mechanical gear A1, an unwinding disk S1, and a winding disk S2. The traction inverter P1 controls the traction motor M1 to drive the wire to move in the tower wheel mold to complete the change of the wire diameter from thick to thin. The winding inverter P2 controls the operation of the winding motor M2 according to the motor line speed and operation command input by the traction inverter P1. In the process of the winding inverter P2 controlling the operation of the winding motor M2, the winding inverter P2 will adjust the tension PI parameter according to the preset tension given threshold and the tension feedback value, so as to superimpose the tension frequency on the main operating frequency of the winding inverter P2, realize constant line speed control, so that the swing rod in the dual-frequency winding and unwinding system is in a set equilibrium position, and the purpose of constant tension control is achieved. It should be noted that this example does not specifically limit the structure of the dual-frequency winding and unwinding system.

[0067] Based on this, the present application proposes a constant tension control method of the first embodiment, which is applied to the winding inverter in the dual-frequency winding and unwinding system. The dual-frequency winding and unwinding system also includes a traction motor and a winding motor. Please refer to Figure 2 , the constant tension control method comprises:

[0068] Step S10, obtaining the motor linear speed of the traction motor and the tension feedback value of the tension detection area, and determining the tension control mode of the winding inverter, wherein the tension control mode includes a winding start control mode and an unwinding start control mode;

[0069] It should be noted that the traction motor is used to drive the operation of the dual-frequency winding and unwinding system. The tension feedback value refers to the tension value detected in the tension detection area. A tension detector can be set in the tension detection area to collect the tension feedback value of the tension detection area through the tension detector. The number of tension detectors can be one or more, and this embodiment does not limit this. The tension control mode is used to indicate the winding and unwinding start state of the winding inverter. The tension control mode may include an unwinding start control mode and a winding start control mode. The unwinding start control mode is used to indicate that the winding inverter is unwinding, and the winding start control mode is used to indicate that the winding inverter is winding. When determining the tension control mode of the winding inverter, since the rotation direction of the winding inverter is opposite during winding and unwinding, the tension control mode of the winding inverter can be determined by judging the rotation direction of the winding inverter.

[0070] In order to further improve the control accuracy of tension, the obtained tension feedback value can be processed by zero-speed tension and taper tension calculation. The specific processing logic of zero-speed tension processing is as follows:

[0071]

[0072] Among them, T zspdeal It represents the tension feedback value obtained after zero-speed tension processing, T targset Indicates the preset tension threshold, T zspd Indicates the tension feedback value before processing, V line Indicates the motor linear speed, V zsodth Indicates the critical line speed for zero-speed tension processing. When the motor line speed is greater than or equal to the critical line speed for zero-speed tension processing, there is no need to perform zero-speed tension processing on the tension feedback value. When the motor line speed is less than the critical line speed for zero-speed tension processing, there is a need to perform zero-speed tension processing on the tension feedback value.

[0073] After the obtained tension feedback value is processed for zero-speed tension, the tension feedback value needs to be calculated for taper tension. The specific calculation formula is as follows:

[0074]

[0075] Wherein, formula (1) represents the calculation formula of linear taper tension, formula (2) represents the calculation formula of curved taper tension, T tapercal It indicates the tension feedback value obtained after the taper tension calculation, T zspdeal It indicates the tension feedback value obtained after zero-speed tension processing, and it indicates the tension taper value, D cur Indicates the current roll diameter, D max Indicates the maximum roll diameter, D0 indicates the empty roll diameter, D compIndicates the tension taper curve compensation value. To facilitate understanding of the current roll diameter D cur 、Initial roll diameter D init , Maximum roll diameter D max The difference between the empty roll diameter D0 can be referred to Figure 3 , Figure 3 A schematic diagram that intuitively shows the wire in different coil diameters.

[0076] Step S20, determining the operating frequency of the winding inverter according to the motor linear speed, the tension feedback value and the tension control mode;

[0077] It should be noted that the operating frequency is used to characterize the operating frequency that the winding inverter needs to reach in order to generate constant tension in the dual-frequency winding and unwinding system.

[0078] Step S30, controlling the winding motor to rotate according to the operating frequency to generate a constant tension in the dual-frequency variable winding and unwinding system.

[0079] An embodiment of the present application provides a constant tension control method, which is applied to a winding inverter in a dual-frequency winding and unwinding system. The dual-frequency winding and unwinding system also includes a traction motor and a winding motor. The embodiment of the present application first obtains the motor line speed of the traction motor and the tension feedback value of the tension detection area, and determines the tension control mode of the winding inverter, which includes a winding start control mode and an unwinding start control mode; then, according to the motor line speed, the tension feedback value and the tension control mode, the operating frequency of the winding inverter output to the winding motor is determined; finally, according to the operating frequency, the winding motor is controlled to rotate to generate a constant tension in the dual-frequency winding and unwinding system. The embodiment of the present application directly determines the operating frequency required to be output to the winding motor in the winding frequency converter, so as to control the rotation of the winding motor through the determined operating frequency, and then generate a constant tension in the dual-frequency winding and unwinding system through the rotation of the winding motor, thereby eliminating the need to use other equipment to determine the required operating frequency of the winding frequency converter, overcoming the technical defect that the winding frequency converter needs to wait until it receives the operating frequency transmitted by other equipment before controlling the motor to rotate at the corresponding frequency, solving the technical problem of low control accuracy of the existing tension control method, and improving the tension control accuracy.

[0080] In a possible implementation, the step of determining the operating frequency output by the winding inverter to the winding motor according to the motor linear speed, the tension feedback value and the tension control mode includes:

[0081] Step S21, determining the tension value interval in which the tension feedback value is located according to the motor linear speed and the tension control mode;

[0082] As an example, the step of determining the tension value interval in which the tension feedback value is located based on the motor linear speed and the tension control mode includes: determining an interval judgment condition based on the motor linear speed and the tension control mode, and determining the tension value interval in which the tension feedback value is located based on the interval judgment condition.

[0083] Step S22, determining the operating frequency outputted to the winding motor by the winding frequency converter corresponding to the tension value interval.

[0084] As an example, when the tension control mode is the winding start control mode, the step of determining the operating frequency output to the winding motor by the winding frequency converter corresponding to the tension value interval includes:

[0085] Step A21, obtaining the actual frequency outputted from the winding frequency converter to the winding motor;

[0086] It should be noted that the actual frequency refers to the main operating frequency output by the winding inverter to the winding motor at the current time point.

[0087] As an example, the actual frequency of the winding inverter is calculated as follows:

[0088]

[0089] Among them, f main1 represents the first target frequency, V line Indicates the motor linear speed, n p Indicates the number of pole pairs of the winding motor, R mechgr Indicates the mechanical gear ratio of the winding motor, D cur1 Indicates the first roll diameter.

[0090] Step A22, if it is verified that the motor linear speed is less than or equal to the first preset linear speed threshold, or it is verified that the motor linear speed is greater than or equal to the second preset linear speed threshold, then determining a first tension difference between a preset tension given threshold and a tension switching value corresponding to the motor linear speed;

[0091] It should be noted that the second preset linear speed threshold is greater than the first preset linear speed threshold. The purpose of checking whether the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold is to determine whether the winding inverter is in the soft start hysteresis zone, that is, the first preset linear speed threshold is used to represent the minimum linear speed of the winding inverter entering the soft start hysteresis zone, and the first preset linear speed threshold is used to represent the maximum linear speed of the winding inverter entering the soft start hysteresis zone. It can be understood that when the winding inverter is in the soft start hysteresis zone, the adjustment conditions of the working frequency of the winding inverter will become wider than before. For example, the original motor linear speed is less than 10 and the working frequency of the inverter needs to be adjusted. When the winding inverter is in the soft start hysteresis zone, the motor linear speed is less than 9 and the working frequency of the inverter needs to be adjusted.

[0092] It should be noted that the first tension difference is used to indicate the tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed in this embodiment, so as to distinguish it from the tension differences mentioned in other embodiments.

[0093] Step A23, if the tension feedback value is less than the first tension difference value, the sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor;

[0094] It should be noted that the preset soft start frequency is used to represent that when the winding inverter is less affected by the tension in the system when driving the winding motor for winding, in order to maintain the driving stability of the winding inverter when driving the winding motor, it is necessary to assist in increasing the operating sub-frequency of the winding inverter.

[0095] It can be understood that when the tension control mode is the winding start control mode, if the tension feedback value is less than the first tension difference, it means that the winding inverter is less affected by the tension in the system when driving the winding motor for winding, and can be ignored. Therefore, there is no risk of belt breakage. The sum of the preset soft start frequency and the actual frequency is used as the operating frequency of the winding inverter output to the winding motor.

[0096] Step A24, if the tension feedback value is greater than or equal to the first tension difference, obtaining a first tension frequency corresponding to the tension feedback value, and determining a first target frequency of the winding inverter according to the motor linear speed;

[0097] It should be noted that the tension frequency is used to indicate that when the winding inverter is greatly affected by the tension in the system when driving the winding motor to wind, in order to maintain the driving stability of the winding inverter when driving the winding motor, it is necessary to increase the operating sub-frequency of the winding inverter. The first tension frequency is used to indicate the tension frequency corresponding to the tension feedback value in this embodiment to distinguish it from the tension frequency corresponding to the tension feedback value mentioned in other embodiments. The target frequency refers to the main operating frequency that the winding inverter needs to output to the winding motor when eliminating the influence of tension. The first target frequency is used to indicate the target frequency in this embodiment to distinguish it from the target frequency mentioned in other embodiments.

[0098] It can be understood that, when the tension control mode is the winding start control mode, if the tension feedback value is greater than or equal to the first tension difference, it means that the winding inverter is greatly affected by the tension in the system when driving the winding motor for winding, and there is a risk of belt breakage. It is necessary to use the sum of the first tension frequency corresponding to the tension feedback value and the first target frequency determined according to the motor linear speed as the operating frequency of the winding inverter output to the winding motor to eliminate the influence of tension when the winding inverter drives the winding motor to run, avoid the risk of belt breakage, and maintain the stable operation of the winding motor.

[0099] Step A25, taking the sum of the first tension frequency and the first target frequency as the operating frequency output by the winding frequency converter to the winding motor.

[0100] In this example, when the tension control mode is the winding start control mode, the actual frequency of the winding inverter is first obtained. If the motor linear speed is less than or equal to the first preset linear speed threshold, or greater than or equal to the second preset linear speed threshold, it means that the winding inverter is not in the soft start hysteresis zone, and the operating frequency of the winding inverter can be determined according to normal adjustment conditions. Then, the first tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed is first determined. If the tension feedback value is less than the first tension difference, it means that the winding inverter is less affected by the tension in the system when driving the winding motor for winding, which can be ignored. Therefore, there is no risk of belt breakage, and then The sum of the preset soft start frequency and the actual frequency is used as the operating frequency of the winding inverter output to the winding motor; if the tension feedback value is greater than or equal to the first tension difference, it means that the winding inverter is greatly affected by the tension in the system when driving the winding motor to wind, and there is a risk of belt breakage. It is necessary to use the sum of the first tension frequency corresponding to the tension feedback value and the first target frequency determined according to the motor linear speed as the operating frequency of the winding inverter output to the winding motor to eliminate the influence of tension when the winding inverter drives the winding motor to run, avoid the risk of belt breakage, maintain the stable operation of the winding motor, and ensure that constant tension can be generated in the dual frequency conversion winding and unwinding system.

[0101] As another example, when the tension control mode is the unwinding start control mode, the step of determining the operating frequency outputted to the winding motor by the winding frequency converter corresponding to the tension value interval includes:

[0102] Step B21, obtaining the actual frequency of the winding frequency converter;

[0103] Step B22, if it is verified that the tension feedback value is greater than the preset tension given threshold, then verify whether the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold;

[0104] When the tension control mode of the winding inverter is the unwinding start control mode, the soft-start hysteresis zone can also be set in the speed range where the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold. However, in actual applications, it is found that the unwinding effect is better when the soft-start hysteresis zone is not set in the unwinding start control mode than when the soft-start hysteresis zone is set.

[0105] Step B23, if it is verified that the motor linear speed is less than or equal to the first preset linear speed threshold, or if it is verified that the motor linear speed is greater than or equal to the second preset linear speed threshold, then determine the tension and value of the tension switching value corresponding to the preset tension given threshold and the motor linear speed;

[0106] Step B24, if the tension feedback value is greater than the tension sum value, the sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor;

[0107] It can be understood that when the tension control mode is the unwinding start control mode, if the tension feedback value is greater than the tension sum value, it means that the winding inverter is less affected by the tension in the system when driving the winding motor for unwinding, and can be ignored. Therefore, there is no risk of belt breakage. The sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor.

[0108] Step B25, if the tension feedback value is less than or equal to the tension sum value, obtaining a second tension frequency corresponding to the tension feedback value, and determining a second target frequency of the winding inverter according to the motor linear speed;

[0109] It should be noted that the second tension frequency is used to indicate the tension frequency corresponding to the tension feedback value in this embodiment, so as to distinguish it from the tension frequencies corresponding to the tension feedback values ​​mentioned in other embodiments, and the second target frequency is used to indicate the target frequency in this embodiment, so as to distinguish it from the target frequencies mentioned in other embodiments.

[0110] It can be understood that, when the tension control mode is the unwinding start control mode, if the tension feedback value is less than or equal to the tension sum value, it means that the winding inverter is greatly affected by the tension in the system when driving the winding motor for unwinding, and there is a risk of belt breakage. In this case, the sum of the second tension frequency corresponding to the tension feedback value and the second target frequency determined according to the motor linear speed needs to be used as the operating frequency output by the winding inverter to the winding motor to eliminate the influence of tension when the winding inverter drives the winding motor to run, avoid the risk of belt breakage, and maintain the stable operation of the winding motor.

[0111] Step B26, taking the sum of the second tension frequency and the second target frequency as the operating frequency output by the winding inverter to the winding motor.

[0112] In this example, when the tension control mode is the unwinding start control mode, the actual frequency of the winding inverter is first obtained. If the tension feedback value is greater than the preset tension given threshold, it means that there is no risk of tape jamming in the dual-frequency winding and unwinding system. Then, when the motor line speed is less than or equal to the first preset line speed threshold, or the motor line speed is greater than or equal to the second preset line speed threshold, the tension sum of the preset tension given threshold and the tension switching value corresponding to the motor line speed is determined. If the tension feedback value is greater than the tension sum, it means that the winding inverter is less affected by the tension in the system when driving the winding motor for unwinding, which can be ignored, and therefore there is no risk of tape breakage. , then the sum of the preset soft start frequency and the actual frequency is used as the working frequency of the winding inverter output to the winding motor. If the tension feedback value is less than or equal to the tension sum value, it means that the winding inverter is greatly affected by the tension in the system when driving the winding motor to unwind, and there is a risk of belt breakage. It is necessary to use the sum of the second tension frequency corresponding to the tension feedback value and the second target frequency determined according to the motor linear speed as the working frequency of the winding inverter output to the winding motor to eliminate the tension influence of the winding inverter when driving the winding motor to run, avoid the risk of belt breakage, maintain the stable operation of the winding motor, and ensure that constant tension can be generated in the dual frequency conversion winding and unwinding system.

[0113] In a possible implementation, the step of obtaining the first tension frequency corresponding to the tension feedback value and determining the first target frequency of the winding inverter according to the motor linear speed includes:

[0114] Step A251, calculating a first tension frequency corresponding to the tension feedback value through a PID algorithm according to the tension feedback value and the motor linear speed;

[0115] Before calculating the first tension frequency corresponding to the tension feedback value through the PID (Proportion Integarl Differential) algorithm, the PI parameters in the PID algorithm can be optimized first. After the optimization is completed, the optimized PID algorithm is used to calculate the first tension frequency corresponding to the tension feedback value.

[0116] As an example, the PI parameters can be optimized by the coil diameter. The specific optimization calculation formula is as follows:

[0117]

[0118] Among them, k p Indicates the tension PI control self-adjusting proportional parameter, k p1 Indicates the tension PI control proportional gain 1, k p2 Indicates tension PI control proportional gain 2, D cur Indicates the current roll diameter, D max represents the maximum roll diameter, D0 represents the empty roll diameter, k i Indicates the tension PI control self-adjusting integral parameter, T i1 Indicates the tension PI control integral time 1, T i2 Indicates tension PI control integral time 2.

[0119] As another example, the PI parameters can be optimized by the operating frequency of the winding motor. The specific optimization calculation formula is as follows:

[0120]

[0121] Among them, k p Indicates the tension PI control self-adjusting proportional parameter, k p1 Indicates the tension PI control proportional gain 1, k p2 Indicates the tension PI control proportional gain 2, f out Indicates the operating frequency of the winding motor, f max Indicates the maximum operating frequency of the winding motor, f min Indicates the minimum operating frequency of the winding motor, k i Indicates the tension PI control self-adjusting integral parameter, T i1 Indicates the tension PI control integral time 1, T i2 Indicates tension PI control integral time 2.

[0122] Step A252, calculating a first winding diameter according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the operating frequency of the winding motor;

[0123] It should be noted that the pole pair number refers to the number of magnetic pole pairs contained in each phase of the winding motor, the mechanical gear ratio refers to the diameter ratio of the gears inside the winding motor, the winding diameter refers to the diameter of the rolled object, and the first winding diameter refers to the winding diameter when the winding motor is less affected by tension.

[0124] As an example, the calculation formula for obtaining the first winding diameter according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the operating frequency of the winding motor is as follows:

[0125]

[0126] Among them, D cur1 Indicates the first coil diameter, V line Indicates the motor linear speed, n p Indicates the number of pole pairs of the winding motor, R mechgr Indicates the mechanical gear ratio of the winding motor, f out Indicates the operating frequency of the winding motor.

[0127] Step A253, calculating a second winding diameter through a PID algorithm according to the motor linear speed and the first winding diameter;

[0128] It should be noted that the second winding diameter refers to the winding diameter required to offset the influence of tension on the winding motor.

[0129] It is understandable that if the winding inverter is greatly affected by the tension in the system when driving the winding motor, then when determining the winding diameter, it is necessary to use the PID algorithm to compensate for the winding diameter according to the motor linear speed to eliminate the influence of the tension on the winding diameter.

[0130] Step A254, calculating the first target frequency of the winding inverter according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the second winding diameter.

[0131] As an example, the calculation formula for calculating the first target frequency according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the second winding diameter is as follows:

[0132]

[0133] Among them, f main2 represents the first target frequency, V line Indicates the motor linear speed, n p Indicates the number of pole pairs of the winding motor, R mechgr Indicates the mechanical gear ratio of the winding motor, D cur2 Indicates the second roll diameter.

[0134] In this embodiment, the first tension frequency corresponding to the tension feedback value is calculated by the PID algorithm, and then the first winding diameter is calculated according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the operating frequency of the winding motor. Then, the winding diameter required to offset the influence of tension on the winding motor is calculated according to the motor linear speed and the first winding diameter by the PID algorithm, that is, the second winding diameter is calculated, and then the second winding diameter is used to determine the main operating frequency required to eliminate the influence of tension by the winding inverter, that is, the first target frequency. Therefore, this embodiment uses the PID algorithm to compensate for the winding diameter according to the motor linear speed to eliminate the influence of tension on the winding diameter, and then determines the operating frequency of the winding inverter according to the compensated winding diameter to eliminate the influence of tension when the winding inverter drives the winding motor to run, avoid the risk of belt breakage, and maintain the stable operation of the winding motor.

[0135] In a possible implementation, the constant tension control method further includes:

[0136] Step A221, if it is verified that the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold, then obtaining the motor linear speed of the traction motor at the next time step;

[0137] Step A222, if the motor linear speed in the next time step is within the linear speed range corresponding to the first preset linear speed threshold, or within the linear speed range corresponding to the second preset linear speed threshold, then maintain the operating frequency output by the winding inverter to the winding motor at the actual frequency.

[0138] For example, assuming that the first preset linear speed threshold is 10, the second preset linear speed threshold is 20, the linear speed range corresponding to the first preset linear speed threshold is 9-10, the linear speed range corresponding to the second preset linear speed threshold is 20 to 21, and the motor linear speed is 11. If the motor linear speed of the traction motor in the next time step is 9.5, the operating frequency of the winding inverter continues to be maintained at the actual frequency. If the motor linear speed of the traction motor in the next time step is 8, it is necessary to adjust the operating frequency of the winding inverter output to the winding motor.

[0139] In this embodiment, if the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold, it means that the winding inverter is in the soft start hysteresis zone. At this time, even if the motor linear speed of the next time step is less than the first preset linear speed threshold or greater than the second preset linear speed threshold, as long as the motor linear speed of the next time step is within the linear speed range corresponding to the first preset linear speed threshold, or within the linear speed range corresponding to the second preset linear speed threshold, the operating frequency output from the winding inverter to the winding motor will not be adjusted, but the operating frequency output from the winding inverter to the winding motor will continue to be maintained, thereby effectively avoiding large fluctuations in the tension in the dual frequency conversion winding and unwinding system caused by repeated switching of the operating frequency output from the winding inverter to the winding motor, thereby improving the stability of the tension in the dual frequency conversion winding and unwinding system.

[0140] In a possible implementation, the constant tension control method further includes:

[0141] Step B221, if it is verified that the tension feedback value is less than or equal to the preset tension given threshold, determining a second tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed;

[0142] It should be noted that the second tension difference is used to indicate the tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed in this embodiment, so as to distinguish it from the tension difference mentioned in other embodiments.

[0143] Step B222, if the tension feedback value is less than the second tension difference value, using the preset reverse cutoff frequency as the operating frequency output by the winding inverter to the winding motor;

[0144] It can be understood that if the tension feedback value is less than or equal to the preset tension given threshold, the unwinding speed in the dual frequency conversion unwinding and rewinding system is slow, and the slow unwinding speed will make the tape looser, which can easily cause tape jams. In order to avoid the risk of tape jams in the dual frequency conversion unwinding and rewinding system, if the tension feedback value is less than the second tension difference, the preset reverse cutoff frequency can be used as the operating frequency of the winding inverter output to the winding motor, so that the winding inverter controls the winding motor to retract some rolls before unwinding.

[0145] Step B223, if the tension feedback value is greater than or equal to the second tension difference value, obtaining a third tension frequency corresponding to the tension feedback value, and determining a third target frequency of the winding inverter according to the motor linear speed;

[0146] It should be noted that the third tension frequency is used to indicate the tension frequency corresponding to the tension feedback value in this embodiment, so as to distinguish it from the tension frequencies corresponding to the tension feedback values ​​mentioned in other embodiments, and the third target frequency is used to indicate the target frequency in this embodiment, so as to distinguish it from the target frequencies mentioned in other embodiments.

[0147] Step B224, taking the sum of the third tension frequency and the third target frequency as the operating frequency output by the winding inverter to the winding motor.

[0148] In this embodiment, if the tension feedback value is less than or equal to the preset tension given threshold value, the unwinding speed in the dual frequency conversion unwinding system is slow at this time, and the slow unwinding speed will make the tape looser, which is easy to cause tape jamming. In order to avoid the risk of tape jamming in the dual frequency conversion unwinding system, if the tension feedback value is less than the second tension difference, the preset reversal cutoff frequency can be used as the working frequency output by the winding frequency converter to the winding motor, so that the winding frequency converter controls the winding motor to recycle some rolls before unwinding; and if the tension feedback value is greater than or equal to the second tension difference, the sum of the third tension frequency corresponding to the tension feedback value and the third target frequency determined according to the motor linear speed can be used as the working frequency output by the winding frequency converter to the winding motor, so as to avoid the risk of tape jamming in the dual frequency conversion unwinding system by increasing the unwinding speed in the dual frequency conversion unwinding system, maintain the stable operation of the winding motor, and thus ensure that constant tension can be generated in the dual frequency conversion unwinding system.

[0149] Embodiment 2

[0150] Based on the first embodiment of the present application, in another embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can be referred to the above introduction, and will not be repeated in the following. Figure 4 The dual-frequency rewinding and unwinding system further includes a rewinding disk. After the step of controlling the rotation of the rewinding motor according to the working frequency, the constant tension control method further includes:

[0151] Step S40, if it is verified that the winding reel in the storage state is in a full reel state, then the actual frequency output by the winding inverter to the winding motor is obtained, and the winding change pre-drive frequency corresponding to the actual frequency is calculated;

[0152] It should be noted that the storage state is used to indicate that the collection reel is storing the tape, the full reel state is used to indicate that the collection reel can no longer store the tape, and the reel change pre-drive frequency is used to characterize the operating frequency that the reel motor needs to reach when replacing the reel for storing the tape in the dual frequency conversion reeling and unwinding system.

[0153] As an example, the consensus for calculating the roll-changing pre-driving frequency corresponding to the actual frequency is as follows:

[0154] f predrv =f main *(1+k predrv )

[0155] Among them, f predrv Indicates the pre-drive frequency for roll change, f main Indicates the actual frequency, k predrv Indicates the frequency gain during the operation of replacing the take-up reel for storing the take-up tape.

[0156] Step S50, adjusting the working frequency outputted from the winding frequency converter to the winding motor to the reel-changing pre-driving frequency, so as to control the winding motor to switch to the winding reel in an empty reel state for winding.

[0157] In this embodiment, if it is verified that the winding reel in the storage state is in a full reel state, it means that the winding reel for storing the take-up tape needs to be replaced at this time, and the pre-drive frequency for reel change corresponding to the actual frequency is calculated, that is, the operating frequency that the winding motor needs to reach when changing reels is calculated, and then the operating frequency output by the winding inverter to the winding motor is adjusted to the pre-drive frequency for reel change, so as to realize the automatic reel changing process in the dual frequency conversion reeling and unwinding system, thereby avoiding the influence of manual reel changing on production efficiency and improving the efficiency of reel changing.

[0158] In a possible implementation, the constant tension control method further includes:

[0159] Step S01, when the motor linear speed is greater than a third preset linear speed threshold, controlling the traction motor and the winding motor to stop rotating, wherein the third preset linear speed threshold is greater than the second preset linear speed threshold.

[0160] It should be noted that the third preset linear speed threshold is used to represent the maximum linear speed that the traction motor can reach when no abnormal line breakage occurs in the dual-frequency conversion rewinding and unwinding system.

[0161] In this implementation, if the motor linear speed is greater than the third preset linear speed threshold, it means that the motor linear speed of the traction motor is too large. At this time, a wire break abnormality may occur in the dual frequency conversion rewinding and unwinding system. In order to avoid the safety problems caused by the wire break abnormality, it is necessary to control the traction motor and the rewinding motor to stop rotating to improve the safety of the dual frequency conversion rewinding and unwinding system.

[0162] To help understand the technical concept or technical principle of this application, please refer to Figure 5 , Figure 5A brief flow diagram of a constant tension control method is provided. Specifically, first, according to the motor line speed, the tension feedback value and the preset tension given threshold, it is determined whether the winding inverter is in a soft start control mode or a tension PI adjustment control mode. If the winding inverter is in the soft start control mode, the sum of the preset soft start frequency and the main frequency (corresponding to the above-mentioned actual frequency) is used as the working frequency output by the winding inverter to the winding motor; and if the winding inverter is in the tension PI adjustment control mode, it is necessary to first perform zero-speed tension processing and taper tension correction on the detected tension feedback value, determine the tension frequency corresponding to the corrected tension feedback value, and then use the sum of the tension frequency and the main frequency as the working frequency output by the winding inverter to the winding motor; at the same time, whether the winding reel in the storage state is in a full reel state will be continuously detected in the dual frequency conversion winding and unwinding system. If it is detected that the winding reel in the storage state is in a full reel state, the winding inverter is controlled to enter the pre-drive roll change mode to control the winding motor to switch to the winding reel in the empty reel state for winding.

[0163] It should be noted that the above specific embodiments are only used to understand the present application and do not constitute a limitation on the constant tension control method of the present application. More simple transformations based on this technical concept are all within the protection scope of the present application.

[0164] Embodiment 3

[0165] The embodiment of the present invention also provides a constant tension control device, which is applied to a winding frequency converter in a dual-frequency winding and unwinding system. The dual-frequency winding and unwinding system also includes a traction motor and a winding motor. Figure 6 , the constant tension control device comprises:

[0166] An acquisition module 10 is used to acquire the motor linear speed of the traction motor and the tension feedback value of the tension detection area, and determine the tension control mode of the winding inverter, wherein the tension control mode includes a winding start control mode and an unwinding start control mode;

[0167] A determination module 20, configured to determine the operating frequency output by the winding inverter to the winding motor according to the motor linear speed, the tension feedback value and the tension control mode;

[0168] The control module 30 is used to control the rotation of the winding motor according to the working frequency to generate a constant tension in the dual-frequency conversion winding and unwinding system.

[0169] Optionally, the determining module 20 is further configured to:

[0170] Determining a tension value interval in which the tension feedback value is located according to the motor linear speed and the tension control mode;

[0171] Determine the operating frequency of the winding frequency converter output to the winding motor corresponding to the tension value range.

[0172] Optionally, when the tension control mode is a winding start control mode, the determining module 20 is further configured to:

[0173] Obtaining the actual frequency outputted from the winding frequency converter to the winding motor;

[0174] If it is verified that the motor linear speed is less than or equal to the first preset linear speed threshold, or if it is verified that the motor linear speed is greater than or equal to the second preset linear speed threshold, a first tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed is determined;

[0175] If the tension feedback value is less than the first tension difference value, the sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor;

[0176] If the tension feedback value is greater than or equal to the first tension difference value, a first tension frequency corresponding to the tension feedback value is obtained, and a first target frequency of the winding frequency converter is determined according to the motor linear speed;

[0177] The sum of the first tension frequency and the first target frequency is used as the operating frequency output by the winding inverter to the winding motor.

[0178] Optionally, the determining module 20 is further configured to:

[0179] According to the tension feedback value and the motor linear speed, a first tension frequency corresponding to the tension feedback value is calculated by a PID algorithm;

[0180] Calculate the first winding diameter according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the operating frequency of the winding motor;

[0181] According to the motor linear speed and the first coil diameter, a second coil diameter is calculated by a PID algorithm;

[0182] The first target frequency of the winding inverter is calculated according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the second winding diameter.

[0183] Optionally, the determining module 20 is further configured to:

[0184] If it is verified that the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold, then obtaining the motor linear speed of the traction motor at the next time step;

[0185] If the motor linear speed at the next time step is within the linear speed range corresponding to the first preset linear speed threshold, or within the linear speed range corresponding to the second preset linear speed threshold, the operating frequency output by the winding inverter to the winding motor is maintained at the actual frequency.

[0186] Optionally, when the tension control mode is an unwinding start control mode, the determining module 20 is further configured to:

[0187] Obtaining the actual frequency of the winding frequency converter;

[0188] If it is verified that the tension feedback value is greater than the preset tension given threshold, then verify whether the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold;

[0189] If it is verified that the motor linear speed is less than or equal to the first preset linear speed threshold, or if it is verified that the motor linear speed is greater than or equal to the second preset linear speed threshold, then determining the tension and value of the tension switching value corresponding to the preset tension given threshold and the motor linear speed;

[0190] If the tension feedback value is greater than the tension sum value, the sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor;

[0191] If the tension feedback value is less than or equal to the tension sum value, a second tension frequency corresponding to the tension feedback value is obtained, and a second target frequency of the winding frequency converter is determined according to the motor linear speed;

[0192] The sum of the second tension frequency and the second target frequency is used as the operating frequency output by the winding inverter to the winding motor.

[0193] Optionally, the determining module 20 is further configured to:

[0194] If it is verified that the tension feedback value is less than or equal to the preset tension given threshold, a second tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed is determined;

[0195] If the tension feedback value is less than the second tension difference value, the preset reverse cutoff frequency is used as the operating frequency outputted from the winding frequency converter to the winding motor;

[0196] If the tension feedback value is greater than or equal to the second tension difference value, a third tension frequency corresponding to the tension feedback value is obtained, and a third target frequency of the winding inverter is determined according to the motor linear speed;

[0197] The sum of the third tension frequency and the third target frequency is used as the operating frequency output by the winding inverter to the winding motor.

[0198] Optionally, the dual frequency conversion reeling and unreeling system further includes a reeling disk, and the constant tension control device further includes:

[0199] If it is verified that the winding reel in the storage state is in a full reel state, the actual frequency output by the winding inverter to the winding motor is obtained, and the reel-changing pre-driving frequency corresponding to the actual frequency is calculated;

[0200] The working frequency outputted from the winding frequency converter to the winding motor is adjusted to the roll-changing pre-driving frequency, so as to control the winding motor to switch to the winding reel in an empty reel state for winding.

[0201] Optionally, the constant tension control device further comprises:

[0202] When the motor linear speed is greater than a third preset linear speed threshold, the traction motor and the winding motor are controlled to stop rotating, wherein the third preset linear speed threshold is greater than the second preset linear speed threshold.

[0203] The constant tension control device provided by the present invention adopts the constant tension control method in the above-mentioned embodiment 1 or embodiment 2, which can solve the technical problem of low control accuracy of the existing tension control method. Compared with the prior art, the beneficial effects of the constant tension control device provided by the embodiment of the present invention are the same as the beneficial effects of the constant tension control method provided by the above-mentioned embodiment, and the other technical features in the constant tension control device are the same as the features disclosed in the above-mentioned embodiment method, which will not be repeated here.

[0204] Embodiment 4

[0205] An embodiment of the present invention provides a frequency converter, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the constant tension control method in the above-mentioned embodiment one.

[0206] Reference below Figure 7, which shows a schematic diagram of the structure of a frequency converter suitable for implementing the embodiment of the present disclosure. The frequency converter in the embodiment of the present disclosure may include but is not limited to mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 7 The frequency converter shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present disclosure.

[0207] like Figure 7 As shown, the frequency converter may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the frequency converter are also stored. The processing device 1001, ROM1002, and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the inverter to communicate with other devices wirelessly or by wire to exchange data. Although the inverter with various systems is shown in the figure, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0208] In particular, according to an embodiment of the present disclosure, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present disclosure includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program contains a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment of the present disclosure are executed.

[0209] The frequency converter provided by the present invention adopts the constant tension control method in the above embodiment, which can solve the technical problem of low control accuracy of the existing tension control method. Compared with the prior art, the beneficial effects of the frequency converter provided by the embodiment of the present invention are the same as the beneficial effects of the constant tension control method provided by the above embodiment, and other technical features in the frequency converter are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0210] It should be understood that the various parts of the present disclosure can be implemented with hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0211] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0212] Embodiment 5

[0213] An embodiment of the present invention provides a computer-readable storage medium having computer-readable program instructions stored thereon, and the computer-readable program instructions are used to execute the constant tension control method in the above-mentioned embodiment 1.

[0214] The computer-readable storage medium provided in the embodiment of the present invention may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0215] The computer-readable storage medium may be included in the frequency converter; or may exist independently without being assembled into the frequency converter.

[0216] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the inverter, the inverter: obtains the motor line speed of the traction motor and the tension feedback value of the tension detection area, and determines the tension control mode of the winding inverter, and the tension control mode includes a winding start control mode and an unwinding start control mode; determines the operating frequency of the winding inverter output to the winding motor according to the motor line speed, the tension feedback value and the tension control mode; controls the rotation of the winding motor according to the operating frequency to generate a constant tension in the dual-frequency winding and unwinding system.

[0217] Computer program code for performing the operations of the present disclosure may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0218] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present invention. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0219] The modules involved in the embodiments described in the present disclosure may be implemented by software or hardware, wherein the name of the module does not limit the unit itself in some cases.

[0220] The readable storage medium provided by the present invention is a computer-readable storage medium, which stores computer-readable program instructions for executing the above-mentioned constant tension control method, and can solve the technical problem of low control accuracy of the existing tension control method. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided by the embodiment of the present invention are the same as the beneficial effects of the constant tension control method provided by the above-mentioned embodiment 1 or embodiment 2, and will not be repeated here.

[0221] Embodiment 6

[0222] An embodiment of the present invention further provides a computer program product, including a computer program, wherein when the computer program is executed by a processor, the steps of the constant tension control method as described above are implemented.

[0223] The computer program product provided by the present application can solve the technical problem of low control accuracy of the existing tension control method. Compared with the prior art, the beneficial effects of the computer program product provided by the embodiment of the present invention are the same as the beneficial effects of the constant tension control method provided by the above-mentioned embodiment 1 or embodiment 2, and will not be repeated here.

[0224] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the present application.

Claims

1. A constant tension control method, characterized in that: A winding frequency converter applied to a dual-frequency winding and unwinding system, wherein the dual-frequency winding and unwinding system further comprises a traction motor and a winding motor, and the constant tension control method comprises: Acquire the motor linear speed of the traction motor and the tension feedback value of the tension detection area, and determine the tension control mode of the winding inverter, wherein the tension control mode includes a winding start control mode and an unwinding start control mode; Determine the operating frequency output by the winding inverter to the winding motor according to the motor linear speed, the tension feedback value and the tension control mode; According to the working frequency, the winding motor is controlled to rotate so as to generate a constant tension in the dual-frequency variable winding and unwinding system.

2. The constant tension control method according to claim 1, characterized in that: The step of determining the operating frequency output by the winding inverter to the winding motor according to the motor linear speed, the tension feedback value and the tension control mode comprises: Determining a tension value interval in which the tension feedback value is located according to the motor linear speed and the tension control mode; Determine the operating frequency of the winding frequency converter output to the winding motor corresponding to the tension value range.

3. The constant tension control method according to claim 2, characterized in that: In the case where the tension control mode is the winding start control mode, the step of determining the operating frequency output to the winding motor by the winding frequency converter corresponding to the tension value interval includes: Obtaining the actual frequency outputted from the winding frequency converter to the winding motor; If it is verified that the motor linear speed is less than or equal to the first preset linear speed threshold, or if it is verified that the motor linear speed is greater than or equal to the second preset linear speed threshold, a first tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed is determined; If the tension feedback value is less than the first tension difference value, the sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor; If the tension feedback value is greater than or equal to the first tension difference value, a first tension frequency corresponding to the tension feedback value is obtained, and a first target frequency of the winding frequency converter is determined according to the motor linear speed; The sum of the first tension frequency and the first target frequency is used as the operating frequency output by the winding inverter to the winding motor.

4. The constant tension control method according to claim 3, characterized in that: The step of obtaining the first tension frequency corresponding to the tension feedback value and determining the first target frequency of the winding inverter according to the motor linear speed includes: According to the tension feedback value and the motor linear speed, a first tension frequency corresponding to the tension feedback value is calculated by a PID algorithm; Calculate the first winding diameter according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the operating frequency of the winding motor; According to the motor linear speed and the first coil diameter, a second coil diameter is calculated by a PID algorithm; The first target frequency of the winding inverter is calculated according to the motor linear speed, the pole pair number of the winding motor, the mechanical gear ratio of the winding motor and the second winding diameter.

5. The constant tension control method according to claim 3, characterized in that: The constant tension control method further comprises: If it is verified that the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold, then obtaining the motor linear speed of the traction motor at the next time step; If the motor linear speed at the next time step is within the linear speed range corresponding to the first preset linear speed threshold, or within the linear speed range corresponding to the second preset linear speed threshold, the operating frequency output by the winding inverter to the winding motor is maintained at the actual frequency.

6. The constant tension control method according to claim 1, characterized in that: In the case where the tension control mode is the unwinding start control mode, the step of determining the operating frequency outputted to the winding motor by the winding frequency converter corresponding to the tension value interval includes: Obtaining the actual frequency of the winding frequency converter; If it is verified that the tension feedback value is greater than the preset tension given threshold, then verify whether the motor linear speed is greater than the first preset linear speed threshold and less than the second preset linear speed threshold; If it is verified that the motor linear speed is less than or equal to the first preset linear speed threshold, or if it is verified that the motor linear speed is greater than or equal to the second preset linear speed threshold, then determining the tension and value of the tension switching value corresponding to the preset tension given threshold and the motor linear speed; If the tension feedback value is greater than the tension sum value, the sum of the preset soft start frequency and the actual frequency is used as the operating frequency output by the winding inverter to the winding motor; If the tension feedback value is less than or equal to the tension sum value, a second tension frequency corresponding to the tension feedback value is obtained, and a second target frequency of the winding frequency converter is determined according to the motor linear speed; The sum of the second tension frequency and the second target frequency is used as the operating frequency output by the winding inverter to the winding motor.

7. The constant tension control method according to claim 6, characterized in that: The constant tension control method further comprises: If it is verified that the tension feedback value is less than or equal to the preset tension given threshold, a second tension difference between the preset tension given threshold and the tension switching value corresponding to the motor linear speed is determined; If the tension feedback value is less than the second tension difference value, the preset reverse cutoff frequency is used as the operating frequency outputted from the winding frequency converter to the winding motor; If the tension feedback value is greater than or equal to the second tension difference value, a third tension frequency corresponding to the tension feedback value is obtained, and a third target frequency of the winding inverter is determined according to the motor linear speed; The sum of the third tension frequency and the third target frequency is used as the operating frequency output by the winding inverter to the winding motor.

8. The constant tension control method according to any one of claims 1 to 7, characterized in that: The dual-frequency rewinding and unwinding system further includes a rewinding disk. After the step of controlling the rotation of the rewinding motor according to the working frequency, the constant tension control method further includes: If it is verified that the winding reel in the storage state is in a full reel state, the actual frequency output by the winding inverter to the winding motor is obtained, and the reel-changing pre-driving frequency corresponding to the actual frequency is calculated; The working frequency outputted from the winding frequency converter to the winding motor is adjusted to the roll-changing pre-driving frequency, so as to control the winding motor to switch to the winding reel in an empty reel state for winding.

9. The constant tension control method according to any one of claims 1 to 7, characterized in that: The constant tension control method further comprises: When the motor linear speed is greater than a third preset linear speed threshold, the traction motor and the winding motor are controlled to stop rotating, wherein the third preset linear speed threshold is greater than the second preset linear speed threshold.

10. A frequency converter, characterized in that: The frequency converter comprises: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the steps of the constant tension control method according to any one of claims 1 to 9.

11. A readable storage medium, characterized in that: The readable storage medium is a computer-readable storage medium, on which is stored a program for implementing the constant tension control method, and the program for implementing the constant tension control method is executed by a processor to implement the steps of the constant tension control method as described in any one of claims 1 to 9.

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