Tension control method for ceramic matrix composite fiber tow

Abstract

The invention relates to the technical field of industrial prepreg production equipment, and particularly discloses a tension control method for ceramic-based composite material fiber tows, the ceramic-based composite material fiber tows are laid and impregnated through a fiber arrangement machine, and the fiber arrangement machine comprises an unwinding roller for unwinding the fiber tows and a take-up roller for taking up the fiber tows. Tension balance of the fiber tows in the fiber arranging machine in the fiber arranging process and the fiber collecting process is achieved by controlling the rotating speed of the unwinding roller and the rotating speed of the fiber collecting roller. The servo motor is adopted to replace a magnetic powder brake to control tension, and the problem that the tension smaller than the resistance range cannot be controlled due to the fact that the resistance of the magnetic powder brake is large is effectively solved; the unwinding roller and the take-up roller are both controlled by servo motors, a double-closed-loop control mode is adopted, tension control is achieved by adjusting the speed difference of the unwinding roller and the take-up roller, the tension control range is widened, stability is better, resistance influence factors are avoided, and the signal oscillation problem caused by one-way control is optimized.

Description

Technical Field

[0001] The invention relates to the technical field of industrial prepreg production equipment, and in particular to a tension control method for ceramic-based composite fiber bundles. Background Art

[0002] The fiber arrangement machine is one of the key equipment in the production of prepregs in the aerospace and electronics industries. It can be used for the production of prepreg non-woven fabrics such as carbon fiber, polymer PE fiber, and aramid fiber. The existing technology uses a servo motor to synchronize the fiber running line speed, feed the yarn when the tension is small, and pre-tighten the yarn when the tension is large. At the same time, in order to eliminate the influence of unilateral tension when the fiber yarn is wound and unwound, a yarn unwinding tension control device is composed of a yarn unwinding roll, an arc guide rod, a centering roller, a tension elimination wheel group, a tension control wheel group, etc.

[0003] At present, it is necessary to use a new material SiC fiber filament to produce related industrial prepregs through a fiber arrangement machine. However, due to the easy-to-break characteristics of SiC fiber filaments, the existing fiber arrangement machines are prone to oscillation during the laying process of SiC fiber filaments due to the reversing action of the servo motor, resulting in unstable tension control and further wire breakage during the tension adjustment process. Summary of the invention

[0004] The object of the present invention is to provide a tension control method for ceramic matrix composite fiber bundles, which has stable tension control and improved tension control accuracy.

[0005] The present invention is achieved through the following technical scheme: a method for controlling the tension of fiber bundles of ceramic-based composite materials, wherein the fiber bundles of ceramic-based composite materials are laid out and dipped in glue by a fiber arrangement machine, and the fiber arrangement machine includes a pay-out roller for releasing the fiber bundles and a take-up roller for taking up the fiber bundles, and the tension balance of the fiber bundles during the release and take-up processes of the fiber arrangement machine is achieved by controlling the rotation speeds of the pay-out roller and the take-up roller.

[0006] In order to better implement the method of the present invention, the fiber arrangement machine further includes a wire guide buffer, a glue dipping assembly, a guide roller, and a glue squeezing roller which are sequentially arranged between the unwinding roller and the winding roller. The glue dipping assembly is placed in a glue tank filled with glue liquid. The ceramic-based composite fiber bundle is released through the unwinding roller, buffered and guided by the wire guide buffer, dipped in glue in the glue tank through the glue dipping assembly, and then guided by the guide roller and the glue squeezing roller to remove excess glue liquid, and finally wound up by the winding roller.

[0007] In order to better implement the method of the present invention, further, the rotational speeds of the unwinding roller and the wire taking-up roller are controlled by a tension control system, and the tension control system includes a first speed control loop for controlling the rotational speed of the unwinding roller, and a second speed control loop for controlling the rotational speed of the wire taking-up roller, and the speed correlation between the first speed control loop and the second speed control loop is achieved through a tension logic operator.

[0008] In order to better implement the method of the present invention, further, the first speed control loop includes a first PID controller, a first linear speed sensor, and a first servo motor; the second speed control loop includes a second PID controller, a second linear speed sensor, and a second servo motor; the first linear speed sensor detects the actual unwinding speed of the wire bundle between the unwinding roller and the wire guide buffer, and the second linear speed sensor detects the actual collecting speed of the wire bundle between the rubber extrusion roller and the collecting roller. The first servo motor controls the rotation speed of the unwinding roller, and the second servo motor controls the rotation speed of the collecting roller.

[0009] In order to better implement the method of the present invention, further, the process of controlling the rotation speeds of the unwinding roller and the wire taking-up roller by the tension control system comprises the following steps:

[0010] Step S1: According to the physical properties of the ceramic matrix composite fiber tow, the theoretical tension T of the ceramic matrix composite fiber tow on the fiber arrangement machine and the theoretical wire release speed V of the ceramic matrix composite fiber tow on the fiber arrangement machine are set. 放 , the theoretical tension T is not greater than the ultimate tension that the ceramic matrix composite fiber tow can withstand;

[0011] Step S2: Detect the actual wire-releasing speed V1 of the wire bundle between the unwinding roller and the wire guide buffer through the first speed sensor, and compare the actual wire-releasing speed V1 with the theoretical wire-releasing speed V 放 The absolute value E1 of the difference is input into the first PID controller, and the first PID controller controls the first servo motor, and the first servo motor is used to control the speed of the unwinding roller, that is, the actual unwinding speed V1 is closer to the theoretical unwinding speed V 放 resizing;

[0012] Step S3: inputting the actual wire-releasing speed V1 detected by the first speed sensor into the tension logic operator, which can run the tension calculation formula of the fiber tow, and calculate the theoretical wire-receiving speed V2 of the wire-receiving roller based on V1 according to the parameters of the fiber tow and the set theoretical tension T;

[0013] Step S4: Detecting the actual wire collection speed V2' of the wire bundle between the rubber squeezing roller and the wire collection roller by the second speed sensor, inputting the absolute value E2 of the difference between the actual wire collection speed V2' and the theoretical wire collection speed V2 based on V1 into the second PID controller, and the second PID controller controls the second servo motor, and uses the second servo motor to control the rotation speed of the wire collection roller, that is, adjusting the actual wire collection speed V2' to the theoretical wire collection speed V2 based on V1;

[0014] Step S5: The first speed sensor and the second speed sensor periodically detect the unwinding or collecting speed of the fiber bundle, so that the first PID controller and the second PID controller periodically send instructions to the first servo motor and the second servo motor, and the first servo motor and the second servo motor realize real-time dynamic adjustment of the rotation speed of the unwinding roller and the collecting roller, so that the tension of the ceramic-based composite fiber bundle on the fiber arrangement machine is always the theoretical tension T.

[0015] In order to better implement the method of the present invention, further, the tension calculation formula of the fiber tow operated by the tension logic operator is:

[0016]

[0017] Wherein, T is the theoretical tension T of the fiber bundle on the fiber arrangement machine, S is the cross-sectional area of ​​the fiber bundle, L is the length of the fiber bundle, E is the elastic modulus of the fiber bundle, and t is the time.

[0018] In order to better implement the method of the present invention, further, the parameters of the first PID controller and the second PID controller include a proportional coefficient Kp, an integral time TN, and a differential time TV, and the proportional coefficient Kp, the integral time TN, and the differential time TV are all obtained by a critical oscillation method.

[0019] In order to better implement the method of the present invention, further, the specific process of obtaining the parameters of the first PID controller and the second PID controller by the critical oscillation method is as follows:

[0020] First, remove the effects of integration and differentiation in the PID controller, that is, set the integration time of the PID controller to the maximum and the differentiation time to zero; make a step change through external interference, observe the measurement value oscillation caused by this, gradually reduce the proportionality from large to small, and observe the oscillation change of the measurement value. If the oscillation is attenuated, continue to reduce the proportionality; if it is divergent, enlarge the proportionality; until the measured value oscillates 4 to 5 times with equal amplitude, the proportional coefficient at this time is the critical proportionality Kb, and the time for one back and forth oscillation is the critical period Kt; according to the critical proportionality and critical period, use the Ziegler-Nichols method to calculate the integral time and differentiation time: Kp=0.6*Kb, TN=0.5*Kt, TV=0.125*Kt.

[0021] In order to better implement the method of the present invention, further, the second PID controller is an incremental PID controller.

[0022] In order to better implement the method of the present invention, it is further characterized by further comprising step S6: evaluating the tension control effect, specifically:

[0023] S61: According to the calculation formula of the tension of the fiber tow, the theoretical tension T of the fiber tow, the theoretical release speed V of the fiber tow 放 , calculate the theoretical fiber collection speed V 收 ;

[0024] S62: The theoretical yarn collection speed V 收 The absolute value E3 of the difference from the actual wire collection speed V2' is used as an evaluation index of the tension control effect;

[0025] S63: The smaller the E3, the better the tension control effect, and vice versa.

[0026] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0027] (1) In view of the easy-to-break characteristics of SiC fiber filaments, the present invention adopts a servo motor to control the rotation speed of the unwinding roller and the winding roller respectively, and controls the tension of the filament bundle by adjusting the rotation speed of the two servo motors, so that the tension is stably controlled;

[0028] (2) The tension control method provided by the present invention replaces the tension control method using a magnetic powder brake, can achieve small tension control, and improve the tension control range to 0-100N. It also has better control stability and high control accuracy, which can reach ±5%, and effectively avoids the problem of being unable to control tension less than the resistance range due to the large resistance of the magnetic powder brake itself.

[0029] (3) The present invention adopts a dual closed-loop control mode and uses a PID regulator to control two servo motors. The speed difference between the unwinding roller and the wire-receiving roller is adjusted by the two servo motors to achieve tension control, thereby avoiding the problem of wire breakage caused by servo motor reversal when a single servo motor is used for control. The present invention is suitable for wide promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments with reference to the following drawings:

[0031] Figure 1 It is a schematic diagram of the fiber bundle control structure in the present invention;

[0032] Figure 2It is a flowchart of a specific control method of the present invention;

[0033] Figure 3 It is a schematic diagram of the three-dimensional structure of the wire guide buffer of the fiber arrangement machine in the present invention.

[0034] Among them: 1-unwinding roller, 2-wire guide buffer, 21-upper frame, 22-lower frame, 23-spring guide column, 24-tow guide wheel, 25-support plate, 26-limiting roller, 3-glue dipping assembly, 4-glue groove, 5-guide roller, 6-glue squeezing roller, 7-wire collecting roller. DETAILED DESCRIPTION

[0035] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0036] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, it is limited that "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly including one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0037] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] Embodiment 1:

[0039] The present embodiment provides a method for controlling the tension of fiber bundles of ceramic-based composite materials, wherein the fiber bundles of ceramic-based composite materials are laid out and impregnated with glue by a fiber arrangement machine, and the fiber arrangement machine comprises a pay-out roller 1 for releasing the fiber bundles and a taking-up roller 7 for taking up the fiber bundles. The method is characterized in that the tension of the fiber bundles during the releasing and taking-up processes of the fiber arrangement machine is balanced by controlling the rotation speeds of the pay-out roller 1 and the taking-up roller 7.

[0040] Embodiment 2:

[0041] Based on the above embodiment, this embodiment further defines the structure of the fiber arrangement machine, such as Figure 1 As shown, the fiber arrangement machine also includes a wire guide buffer 2, a glue dipping assembly 3, a guide roller 5, and a glue squeezing roller 6 which are sequentially arranged between the unwinding roller 1 and the wire taking-up roller 7. The glue dipping assembly 3 is placed in a glue tank 4 containing glue liquid. The ceramic-based composite fiber bundle is released through the unwinding roller 1, buffered and guided by the wire guide buffer 2, glued in the glue tank 4 through the glue dipping assembly 3, and then guided by the guide roller 5 and the glue squeezing roller 6 to remove excess glue liquid, and finally collected by the wire taking-up roller 7.

[0042] The dipping assembly 3 includes at least two dipping rollers arranged in parallel in the glue tank 4 .

[0043] Embodiment 3:

[0044] Based on the above embodiment, this embodiment further limits the rotation speed of the unwinding roller 1 and the wire-receiving roller 7 to be controlled by a tension control system, such as Figure 1 As shown, the tension control system includes a first speed control loop for controlling the rotation speed of the unwinding roller 1, and a second speed control loop for controlling the rotation speed of the wire taking-up roller 7. The speed relationship between the first speed control loop and the second speed control loop is achieved through a tension logic operator.

[0045] The first speed control loop includes a first PID controller, a first linear speed sensor, and a first servo motor; the second speed control loop includes a second PID controller, a second linear speed sensor, and a second servo motor; the first linear speed sensor detects the actual unwinding speed of the wire bundle between the unwinding roller 1 and the wire guide buffer 2, and the second linear speed sensor detects the actual collecting speed of the wire bundle between the rubber squeezing roller 6 and the collecting roller 7. The first servo motor controls the rotation speed of the unwinding roller 1, and the second servo motor controls the rotation speed of the collecting roller 7.

[0046] Embodiment 4:

[0047] Based on the above embodiment, this embodiment further defines the specific process of controlling the rotation speed of the unwinding roller 1 and the wire taking-up roller 7 by the tension control system, such as Figure 2 As shown, the following steps are included:

[0048] Step S1: According to the physical properties of the ceramic matrix composite fiber tow, the theoretical tension T of the ceramic matrix composite fiber tow on the fiber arrangement machine and the theoretical wire release speed V of the ceramic matrix composite fiber tow on the fiber arrangement machine are set. 放 , the theoretical tension T is not greater than the ultimate tension that the ceramic matrix composite fiber tow can withstand;

[0049] Step S2: Detect the actual wire-releasing speed V1 of the wire bundle between the unwinding roller 1 and the wire guide buffer 2 through the first speed sensor, and compare the actual wire-releasing speed V1 with the theoretical wire-releasing speed V 放 The absolute value E1 of the difference is input into the first PID controller, and the first PID controller controls the first servo motor, and uses the first servo motor to control the speed of the unwinding roller 1, that is, the actual unwinding speed V1 is closer to the theoretical unwinding speed V 放 resizing;

[0050] Step S3: inputting the actual wire-releasing speed V1 detected by the first speed sensor into the tension logic operator, which can run the tension calculation formula of the fiber tow, and calculate the theoretical wire-receiving speed V2 of the wire-receiving roller 7 based on V1 according to the parameters of the fiber tow and the set theoretical tension T;

[0051] Step S4: Detecting the actual wire collection speed V2' of the wire bundle between the rubber squeezing roller 6 and the wire collection roller 7 through the second speed sensor, inputting the absolute value E2 of the difference between the actual wire collection speed V2' and the theoretical wire collection speed V2 based on V1 into the second PID controller, and the second PID controller controls the second servo motor, and uses the second servo motor to control the rotation speed of the wire collection roller 7, that is, adjusting the actual wire collection speed V2' to the theoretical wire collection speed V2 based on V1;

[0052] Step S5: The first speed sensor and the second speed sensor periodically detect the unwinding or collecting speed of the fiber tow, so that the first PID controller and the second PID controller periodically send instructions to the first servo motor and the second servo motor, and the first servo motor and the second servo motor realize real-time dynamic adjustment of the rotation speed of the unwinding roller 1 and the collecting roller 2, so that the tension of the ceramic matrix composite fiber tow on the fiber arrangement machine is always the theoretical tension T;

[0053] Step S6: Evaluate the tension control effect, specifically:

[0054] S61: According to the calculation formula of the tension of the fiber tow, the theoretical tension T of the fiber tow, the theoretical release speed V of the fiber tow 放 , calculate the theoretical fiber collection speed V 收 ;

[0055] S62: The theoretical yarn collection speed V 收 The absolute value E3 of the difference from the actual wire collection speed V2' is used as an evaluation index of the tension control effect;

[0056] S63: The smaller the E3, the better the tension control effect, and vice versa.

[0057] Embodiment 5:

[0058] Based on the above embodiment, this embodiment further defines the tension calculation formula of the fiber tow operated by the tension logic operator as follows:

[0059]

[0060] Wherein, T is the theoretical tension T of the fiber bundle on the fiber arrangement machine, S is the cross-sectional area of ​​the fiber bundle, L is the length of the fiber bundle, E is the elastic modulus of the fiber bundle, and t is the time.

[0061] Embodiment 6:

[0062] Based on the above embodiments, this embodiment further limits the parameters of the first PID controller and the second PID controller to include a proportional coefficient Kp, an integral time TN, and a differential time TV, and the proportional coefficient Kp, the integral time TN, and the differential time TV are all obtained by a critical oscillation method.

[0063] The specific process of obtaining the parameters of the first PID controller and the second PID controller by the critical oscillation method is as follows:

[0064] First, remove the effects of integration and differentiation in the PID controller, that is, set the integration time of the PID controller to the maximum and the differentiation time to zero; make a step change through external interference, observe the measurement value oscillation caused by this, gradually reduce the proportionality from large to small, and observe the oscillation change of the measurement value. If the oscillation is attenuated, continue to reduce the proportionality; if it is divergent, enlarge the proportionality; until the measured value oscillates 4 to 5 times with equal amplitude, the proportional coefficient at this time is the critical proportionality Kb, and the time for one back and forth oscillation is the critical period Kt; according to the critical proportionality and critical period, use the Ziegler-Nichols method to calculate the integral time and differentiation time: Kp=0.6*Kb, TN=0.5*Kt, TV=0.125*Kt.

[0065] Embodiment 7:

[0066] Based on the above embodiment, this embodiment further defines the second PID controller as an incremental PID controller. An incremental PID controller refers to a PID controller that performs control by calculating the increment of the control quantity. This method mainly focuses on the increment of the control quantity, combines proportional, integral, and differential control to achieve rapid response and stable control of the system, avoids the accumulation effect of the integral link, and thus reduces computing performance and storage space occupancy.

[0067] Embodiment 8:

[0068] Based on the above embodiment, this embodiment further defines the specific structure of the guide wire buffer 2, such as Figure 3 As shown, the guide wire buffer 2 includes an upper frame 21 and a lower frame 22, and a plurality of spring guide pillars 23 are arranged between the upper frame 21 and the lower frame 22. The upper frame 21 can reciprocate up and down on the upper part of the lower frame 22; a rotatable tow guide wheel 24 is installed on the upper frame 21, and a support plate 25 is fixed on one side of the lower frame 22, and two parallel limiting rollers 26 are fixed on the upper part of the support plate 25. The fiber tow is released through the unwinding roller 1 and enters the guide wire buffer 2, first passes between the two parallel limiting rollers 26 for fiber, and then passes through the tow guide wheel 24 arranged on the upper frame 21. When the tension of the fiber tow increases sharply, the upper frame 21 compresses the spring guide pillars 23 downward, and when the fiber tension decreases, the spring guide pillars 23 lift the upper frame 21 upward to offset the sudden change in tension to maintain constant tension. The fiber tow enters the glue groove after passing through the tow guide wheel 24.

[0069] Before the composite fiber bundles released by the wire-releasing roller 1 are dipped in glue, the composite fiber bundles coming out from different angles need to be guided by the wire guide roller to ensure that the fiber bundles run in the central straight line position. However, since the new material SiC fiber filaments are easy to break, it is very easy for the bundles to break at the wire guide roller, resulting in large tension fluctuations, poor quality of the finished product, and a high scrap rate.

[0070] After analysis, it was found that the output angle of the composite fiber bundle coming out of the wire-releasing roller 1 varies greatly, resulting in large tension fluctuations, and bundle breakage is prone to occur at the wire guide column, which affects the fiber tension control accuracy of the entire process and cannot meet the process requirements.

[0071] After conducting in-depth research on the problems of tow breakage and large tension fluctuations on site, it was found that the yarn outlet angle changes from small to large, and then from large to small in a cycle. The tension fluctuations of the fiber tow collected by the tension sensor also follow the same rule, and the tow breakage is easy to occur at the peak point of the angle turning. Therefore, the traditional wire guide roller was improved.

[0072] The overall frame structure is split into two parts, the upper and lower parts, without changing the original structural form. At the same time, a spring guide column 23 is added in a limited space as an elastic unit. When the fiber tension increases sharply, the elastic unit is compressed downward. When the fiber tension decreases, the elastic unit is lifted upward to offset the sudden change in tension to maintain constant tension.

[0073] Judging from the product quality and process effects after installing the improved wire guide buffer 2, the improved wire guide buffer 2 eliminates the peak point of tension fluctuation, increases the tension control accuracy from 10% to 3%, significantly improves the quality of the finished product, greatly reduces the number of composite fiber breakages, improves production efficiency, and saves maintenance costs.

[0074] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for controlling the tension of a ceramic matrix composite fiber bundle, wherein the ceramic matrix composite fiber bundle is laid out and impregnated with glue by a fiber arranging machine, wherein the fiber arranging machine comprises a pay-off roller (1) for releasing the fiber bundle and a take-up roller (7) for taking up the fiber bundle, characterized in that: By controlling the rotation speeds of an unwinding roller (1) and a collecting roller (7), tension balance of a fiber bundle during the unwinding and collecting processes of a fiber arrangement machine is achieved.

2. A method for controlling the tension of a ceramic matrix composite fiber bundle according to claim 1, characterized in that: The fiber arrangement machine also includes a wire guide buffer (2), a glue dipping assembly (3), a guide roller (5), and a glue squeezing roller (6) which are sequentially arranged between the unwinding roller (1) and the wire taking-up roller (7); the glue dipping assembly (3) is placed in a glue tank (4) containing glue liquid; the ceramic-based composite fiber bundle is released through the unwinding roller (1), buffered and guided by the wire guide buffer (2), glued in the glue tank (4) through the glue dipping assembly (3), guided by the guide roller (5) and the glue squeezing roller (6) to remove excess glue liquid, and finally taken up by the wire taking-up roller (7).

3. A method for controlling the tension of a ceramic matrix composite fiber bundle according to claim 1 or 2, characterized in that: The rotation speeds of the unwinding roller (1) and the wire-collecting roller (7) are controlled by a tension control system, wherein the tension control system comprises a first speed control loop for controlling the rotation speed of the unwinding roller (1) and a second speed control loop for controlling the rotation speed of the wire-collecting roller (7), wherein the first speed control loop and the second speed control loop are linked in speed by a tension logic operator.

4. A method for controlling the tension of a ceramic matrix composite fiber bundle according to claim 3, characterized in that: The first speed control loop includes a first PID controller, a first linear speed sensor, and a first servo motor; the second speed control loop includes a second PID controller, a second linear speed sensor, and a second servo motor; the first linear speed sensor detects the actual unwinding speed of the filament bundle between the unwinding roller (1) and the wire guide buffer (2), and the second linear speed sensor detects the actual collecting speed of the filament bundle between the rubber squeezing roller (6) and the collecting roller (7); the first servo motor controls the rotation speed of the unwinding roller (1), and the second servo motor controls the rotation speed of the collecting roller (7).

5. A method for controlling the tension of a ceramic matrix composite fiber bundle according to claim 4, characterized in that: The process of controlling the rotation speeds of the unwinding roller (1) and the wire-receiving roller (7) by means of the tension control system comprises the following steps: Step S1: According to the physical properties of the ceramic matrix composite fiber tow, the theoretical tension T of the ceramic matrix composite fiber tow on the fiber arrangement machine and the theoretical wire release speed V of the ceramic matrix composite fiber tow on the fiber arrangement machine are set. 放 , the theoretical tension T is not greater than the ultimate tension that the ceramic matrix composite fiber tow can withstand; Step S2: Detecting the actual wire-releasing speed V1 of the wire bundle between the unwinding roller (1) and the wire guide buffer (2) through the first speed sensor, comparing the actual wire-releasing speed V1 with the theoretical wire-releasing speed V 放 The absolute value E1 of the difference is input into the first PID controller, and the first PID controller controls the first servo motor, and uses the first servo motor to control the rotation speed of the unwinding roller (1), that is, the actual unwinding speed V1 is adjusted to the theoretical unwinding speed V 放 resizing; Step S3: inputting the actual wire-releasing speed V1 detected by the first speed sensor into the tension logic operator, which is capable of running a tension calculation formula for the fiber bundle, and calculating the theoretical wire-receiving speed V2 of the wire-receiving roller (7) based on V1 according to the parameters of the fiber bundle and the set theoretical tension T; Step S4: detecting the actual wire collection speed V2' of the wire bundle between the rubber squeezing roller (6) and the wire collection roller (7) by means of a second speed sensor, inputting the absolute value E2 of the difference between the actual wire collection speed V2' and the theoretical wire collection speed V2 based on V1 into a second PID controller, and the second PID controller controls the second servo motor, and uses the second servo motor to control the rotation speed of the wire collection roller (7), that is, adjusting the actual wire collection speed V2' to the theoretical wire collection speed V2 based on V1; Step S5: The first speed sensor and the second speed sensor periodically detect the unwinding or collecting speed of the fiber bundle, so that the first PID controller and the second PID controller periodically send instructions to the first servo motor and the second servo motor, and the first servo motor and the second servo motor realize real-time dynamic adjustment of the rotation speed of the unwinding roller (1) and the collecting roller (2), so that the tension of the ceramic-based composite fiber bundle on the fiber arrangement machine is always the theoretical tension T.

6. A method for controlling the tension of a ceramic matrix composite fiber bundle according to claim 5, characterized in that: The tension calculation formula of the fiber tow operated by the tension logic operator is: Wherein, T is the theoretical tension T of the fiber bundle on the fiber arrangement machine, S is the cross-sectional area of ​​the fiber bundle, L is the length of the fiber bundle, E is the elastic modulus of the fiber bundle, and t is the time.

7. The method for controlling the tension of a ceramic matrix composite fiber bundle according to claim 5, characterized in that: The parameters of the first PID controller and the second PID controller include a proportional coefficient Kp, an integral time TN, and a differential time TV. The proportional coefficient Kp, the integral time TN, and the differential time TV are all obtained by a critical oscillation method.

8. The method for controlling the tension of a ceramic matrix composite fiber bundle according to claim 7, characterized in that: The specific process of obtaining the parameters of the first PID controller and the second PID controller by the critical oscillation method is as follows: First, remove the effects of integration and differentiation in the PID controller, that is, set the integration time of the PID controller to the maximum and the differentiation time to zero; make a step change through external interference, observe the measurement value oscillation caused by this, gradually reduce the proportionality from large to small, and observe the oscillation change of the measurement value. If the oscillation is attenuated, continue to reduce the proportionality; if it is divergent, enlarge the proportionality; until the measured value oscillates 4 to 5 times with equal amplitude, the proportional coefficient at this time is the critical proportionality Kb, and the time for one back and forth oscillation is the critical period Kt; according to the critical proportionality and critical period, use the Ziegler-Nichols method to calculate the integral time and differentiation time: Kp=0.6*Kb, TN=0.5*Kt, TV=0.125*Kt.

9. A method for controlling the tension of a ceramic matrix composite fiber bundle according to claim 8, characterized in that: The second PID controller is an incremental PID controller.

10. A method for controlling the tension of a ceramic matrix composite fiber bundle according to any one of claims 5 to 9, characterized in that: The step S6 is also included: evaluating the tension control effect, specifically: S61: According to the calculation formula of the tension of the fiber tow, the theoretical tension T of the fiber tow, the theoretical release speed V of the fiber tow 放 , calculate the theoretical fiber collection speed V 收 ; S62: The theoretical yarn collection speed V 收 The absolute value E3 of the difference from the actual wire collection speed V2' is used as an evaluation index of the tension control effect; S63: The smaller the E3, the better the tension control effect, and vice versa.

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