Opening and cleaning engineering control system for papermaking felt

Abstract

The invention provides an opening and cleaning engineering control system for a papermaking felt. The system comprises a data acquisition module, a communication module, an execution module and a central control module, the data acquisition module is used for acquiring the state of a fiber raw material, and the state of the fiber raw material comprises the humidity of the fiber raw material, the density of the fiber raw material and the impurity content of the fiber raw material; the communication module is used for communication between the data acquisition module and the control module; the control module is used for adjusting the roller speed, the interval, the cylinder rotating speed and the angle according to the calculation data of the fiber raw materials; the execution module is used for adjusting the roller speed, the interval, the cylinder rotating speed and the angle according to calculation data of the control module, the optimal control input sequence in a period of time in the future can be predicted through the system, and control input is adjusted in real time so as to adapt to changing process conditions and real-time product requirements.

Description

Technical Field

[0001] The invention provides a control system for a blowroom process of a papermaking felt, and relates to the technical field of control.

[0002] Background technology

[0003] In the production of papermaking felts, the blowroom is a critical preliminary step, ensuring the purity and uniformity of the fiber raw material. The primary metric to consider in the opening process is dust removal efficiency. The key to improving dust removal efficiency lies in the blow intensity of the opener's beaters, which is influenced by factors such as their structure and operating speed. Improving dust removal efficiency necessitates high blow intensity, but excessive blow intensity can over-beat the raw cotton, leading to poor transfer and twisting, resulting in excessive neps and short fibers. It can also cause large impurities to break, creating smaller impurities that increase the burden on subsequent processes like carding, further reducing overall dust removal efficiency. This presents a major contradiction in the blowroom operation of the blowroom. Traditional blowroom processes often fail to consider the actual state of the fiber raw material, resulting in suboptimal efficiency and effectiveness. Summary of the Invention

[0004] The present invention provides a control system for the blowroom process of papermaking felts to solve the above-mentioned problems:

[0005] The present invention proposes a control system for the blowroom process of papermaking felts, which includes a data acquisition module, a communication module, an execution module, and a central control module.

[0006] The data acquisition module is used to collect the status of the fiber raw material, and the status of the fiber raw material includes: the humidity of the fiber raw material, the density of the fiber raw material and the impurity content of the fiber raw material;

[0007] The communication module is used for the data acquisition module to communicate with the control module;

[0008] The control module is used to adjust the roller speed, interval, cylinder speed and angle according to the calculated data of the fiber raw material;

[0009] The execution module is used to adjust the roller speed, interval, cylinder speed and angle according to the calculation data of the control module.

[0010] Furthermore, a control system for the cleaning process of papermaking felts is provided, wherein the data acquisition module preprocesses the data collected by the temperature sensor, humidity sensor, density sensor and impurity sensor, and the preprocessing includes filtering out noise and abnormal values in the collected data, and after preprocessing, taking the average value of the data collected by each sensor as the temperature value, humidity value, density value and impurity content value of the fiber raw material.

[0011] Furthermore, a control system for a blowroom process of a papermaking felt is provided, wherein the control module sets the state variable to x(t), the control input to u(t), and the output variable to y(t). The control module sets a dynamic equation. Specifically, the dynamic equation is:

[0012]

[0013]

[0014] in, represents the fiber density change rate, represents the rate of change of humidity, Indicates the rate of change of impurity content, represents the temperature change rate, ρ(t) represents the fiber density, which is affected by the roller speed and impurity content, H(t) represents the humidity, which is affected by the temperature and roller interval, I(t) represents the impurity content, which is affected by the cylinder speed and cylinder angle, and θ(t) represents the temperature, which is affected by the humidity and roller speed.

[0015] Furthermore, a control system for the blowroom process of papermaking felts is provided, wherein the output variables of the control module include fiber density ρ, humidity H and impurity content I, and the output equation is expressed as

[0016]

[0017] Furthermore, in a blowroom control system for a papermaking felt, the optimization objective of the control module is to minimize a cost function. Specifically, the cost function is:

[0018]

[0019] Among them, J represents the cost function, y ref is the reference output under ideal conditions, Q is the weighted matrix of the output error, and R is the weighted matrix of the control input.

[0020] Furthermore, in a blowroom control system for a papermaking felt, the control module optimizes the control input within a future period of time through a predictive control model. Specifically, the predictive control model is:

[0021]

[0022] The constraints of the predictive control model are:

[0023]

[0024] in, represents the derivative of the state variable x(τ) with respect to time τ, which represents the rate of change of the state variable over time. x(t) represents the state variable at the current time t. x0 represents the initial state, which represents the initial value of the state variable at the current time t.

[0025] Furthermore, in a blowroom control system for a papermaking felt, the data acquisition module communicates with the central control module via a CAN bus.

[0026] Further, a control system for a blowroom process of a papermaking felt, wherein the control module uses the output equation y(t)=h(x(t)) to calculate the current fiber density, moisture, temperature, and impurity content to monitor the output;

[0027] Compare the output y(t) with the expected reference output y ref To compare the target state:

[0028] Using a predictive control model to optimize control inputs over a future period of time by minimizing a cost function that takes into account the error in the state (i.e., the difference from the target state) and the cost of the control input;

[0029] Based on the minimization of the dynamic equations and the cost function, the optimal control input u(t) is calculated. Specifically, the system will optimize the control input under the constraints for each time step τ. The control input includes roller speed, spacing, cylinder speed and angle.

[0030] Furthermore, a cleaning engineering control system for papermaking felts comprises: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the cleaning engineering control system for papermaking felts as described in any one of claims 1 to 8.

[0031] The beneficial effects of the present invention are as follows: The design is based on a predictive control model method. For the blowroom process of papermaking felts, the dynamic equation reflects the changes in system state variables (fiber density, moisture, impurity content, and temperature) over time, while taking into account the influence of control inputs (roller speed, roller spacing, cylinder speed, and cylinder angle) on these states. The rate of change of each state variable is described by a linear combination of empirical constants (e.g., -0.05, 0.02, etc.) and control inputs. These constants are determined through system modeling and experiments. The change in fiber density is affected by roller speed and impurity content, which reflects the distribution and density adjustment of fibers during the papermaking process. The change in humidity is affected by temperature and roller spacing, which affects the drying and stability of paper. The impurity content is affected by cylinder speed and cylinder angle, which directly affects the quality and uniformity of paper. The temperature is affected by humidity and roller speed, which is closely related to the paper drying process. The output equation defines the target state of the control system, namely the desired fiber density, moisture, and impurity content. These outputs are the basis of the control algorithm's optimization objectives. The cost function is calculated by comparing the actual state and the target state. The cost function aims to minimize the difference between the system output and the target state, while taking into account the cost of using the control input or other influencing factors. By minimizing the cost function, the predictive control model can predict the optimal control input sequence for a period of time in the future at each time step to adapt to changing process conditions and real-time product requirements. The predictive control model allows the system to adjust the control input in real time to cope with disturbances and changes in the process, thereby improving the system's response speed and stability. This design scheme effectively improves the automation level and production quality of the papermaking process through mathematical modeling and optimization methods, and meets the requirements of modern manufacturing for efficient and precise control. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The present invention provides a flowchart for executing a control system for a blowroom process for papermaking felts. DETAILED DESCRIPTION

[0033] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein may be combined with each other.

[0034] The following description sets forth numerous specific details to facilitate a thorough understanding of the present invention. The embodiments described are merely a portion of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0036] One embodiment of the present invention provides a control system for a blowroom process of a papermaking felt, comprising a data acquisition module, a communication module, an execution module, and a central control module. The data acquisition module is configured to acquire the status of a fiber raw material, wherein the status of the fiber raw material includes: moisture content of the fiber raw material, density of the fiber raw material, and impurity content of the fiber raw material;

[0037] The communication module is used for the data acquisition module to communicate with the control module;

[0038] The control module is used to adjust the roller speed, interval, cylinder speed and angle according to the calculated data of the fiber raw material;

[0039] The execution module is used to adjust the roller speed, interval, cylinder speed and angle according to the calculation data of the control module.

[0040] One embodiment of the present invention is a control system for the cleaning process of a papermaking felt, wherein the data acquisition module preprocesses data collected by a temperature sensor, a humidity sensor, a density sensor, and an impurity sensor, wherein the preprocessing includes filtering out noise and abnormal values in the collected data, and after preprocessing, taking the average value of the data collected by each sensor as the temperature value, humidity value, density value, and impurity content value of the fiber raw material.

[0041] One embodiment of the present invention is a control system for a blowroom process of a papermaking felt, wherein the control module sets a state variable as x(t), a control input as u(t), and an output variable as y(t). The control module sets a dynamic equation. Specifically, the dynamic equation is:

[0042]

[0043] in, represents the fiber density change rate, represents the rate of change of humidity, Indicates the rate of change of impurity content, represents the temperature change rate, ρ(t) represents the fiber density, which is affected by the roller speed and impurity content, H(t) represents the humidity, which is affected by the temperature and roller interval, I(t) represents the impurity content, which is affected by the cylinder speed and cylinder angle, and θ(t) represents the temperature, which is affected by the humidity and roller speed.

[0044] One embodiment of the present invention is a control system for a blowroom process of a papermaking felt, wherein the output variables of the control module include fiber density ρ, humidity H, and impurity content I. The output equation is expressed as follows:

[0045]

[0046] One embodiment of the present invention provides a control system for a blowroom process of a papermaking felt, wherein the optimization objective of the control module is to minimize a cost function. Specifically, the cost function is:

[0047]

[0048] Among them, J represents the cost function, y ref is the reference output under ideal conditions, Q is the weighted matrix of the output error, and R is the weighted matrix of the control input.

[0049] In one embodiment of the present invention, a control system for a blowroom process of a papermaking felt is provided, wherein the control module optimizes control inputs within a future period of time using a predictive control model. Specifically, the predictive control model is:

[0050]

[0051] The constraints of the predictive control model are:

[0052]

[0053] in, represents the derivative of the state variable x(τ) with respect to time τ, which represents the rate of change of the state variable over time. x(t) represents the state variable at the current time t. x0 represents the initial state, which represents the initial value of the state variable at the current time t.

[0054] In one embodiment of the present invention, a blowroom control system for a papermaking felt is provided, wherein the data acquisition module communicates with the central control module via a CAN bus.

[0055] One embodiment of the present invention is a control system for a blowroom process of a papermaking felt, characterized in that the control module uses the output equation y(t)=h(x(t)) to calculate the current fiber density, moisture, temperature, and impurity content to monitor the output;

[0056] Compare the output y(t) with the expected reference output y ref To compare the target state:

[0057] Using a predictive control model to optimize control inputs over a future period of time by minimizing a cost function that takes into account the error in the state (i.e., the difference from the target state) and the cost of the control input;

[0058] Based on the minimization of the dynamic equations and the cost function, the optimal control input u(t) is calculated. Specifically, the system will optimize the control input under the constraints for each time step τ. The control input includes roller speed, spacing, cylinder speed and angle.

[0059] The working principle and effect of the above technical solution are as follows: This design is based on a predictive control model approach. For the blowroom process of papermaking felts, the dynamic equations reflect the time-dependent changes in system state variables (fiber density, moisture content, impurity content, and temperature), while also considering the impact of control inputs (roller speed, roller spacing, cylinder speed, and cylinder angle) on these states. The rate of change of each state variable is described by a linear combination of empirical constants (e.g., -0.05, 0.02, etc.) and control inputs. These constants are determined through system modeling and experiments. Changes in fiber density are affected by roller speed and impurity content, reflecting the distribution and density adjustment of fibers during the papermaking process. Changes in moisture content are affected by temperature and roller spacing, which affect the drying and stability of the paper. Impurity content is affected by cylinder speed and cylinder angle, directly affecting the quality and uniformity of the paper. Temperature is affected by humidity and roller speed, which is closely related to the paper drying process. The output equations define the target state of the control system, namely the desired fiber density, moisture content, and impurity content. These outputs are the basis of the control algorithm's optimization objectives. The cost function is calculated by comparing the actual state and the target state. The cost function aims to minimize the difference between the system output and the target state, while taking into account the cost of using the control input or other influencing factors. By minimizing the cost function, the predictive control model can predict the optimal control input sequence for a period of time in the future at each time step to adapt to changing process conditions and real-time product requirements. The predictive control model allows the system to adjust the control input in real time to cope with disturbances and changes in the process, thereby improving the system's response speed and stability. This design scheme effectively improves the automation level and production quality of the papermaking process through mathematical modeling and optimization methods, and meets the requirements of modern manufacturing for efficient and precise control.

[0060] One embodiment of the present invention is a control system for a cleaning process for papermaking felts, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the control system for a cleaning process for papermaking felts as described in any one of claims 1 to 8.

[0061] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A control system for the blowroom process of papermaking felts, comprising a data acquisition module, a communication module, an execution module, and a central control module, characterized in that: The data acquisition module is used to collect the status of the fiber raw material, and the status of the fiber raw material includes: the humidity of the fiber raw material, the density of the fiber raw material and the impurity content of the fiber raw material; The communication module is used for the data acquisition module to communicate with the control module; The control module is used to adjust the roller speed, interval, cylinder speed and angle according to the calculated data of the fiber raw material; The execution module is used to adjust the roller speed, interval, cylinder speed and angle according to the calculation data of the control module.

2. A control system for a blowroom process of a papermaking felt according to claim 1, characterized in that: The data acquisition module preprocesses the data collected by the temperature sensor, humidity sensor, density sensor and impurity sensor. The preprocessing includes filtering out noise and abnormal values in the collected data. After preprocessing, the average value of the data collected by each sensor is taken as the temperature value, humidity value, density value and impurity content value of the fiber raw material.

3. A control system for a blowroom process of a papermaking felt according to claim 1, characterized in that: The control module sets the state variable to x(t), the control input to u(t), and the output variable to y(t). The control module sets a dynamic equation. Specifically, the dynamic equation is: in, represents the fiber density change rate, represents the rate of change of humidity, Indicates the rate of change of impurity content, represents the temperature change rate, ρ(t) represents the fiber density, which is affected by the roller speed and impurity content, H(t) represents the humidity, which is affected by the temperature and roller interval, I(t) represents the impurity content, which is affected by the cylinder speed and cylinder angle, and θ(t) represents the temperature, which is affected by the humidity and roller speed.

4. A control system for a blowroom process of a papermaking felt according to claim 1, characterized in that: The output variables of the control module include fiber density ρ, humidity H and impurity content I. The output equation is expressed as:

5. The control system for the blowroom process of papermaking felt according to claim 1, characterized in that: The optimization goal of the control module is to minimize the cost function. Specifically, the cost function is: Among them, J represents the cost function, y ref is the reference output under ideal conditions, Q is the weighted matrix of the output error, and R is the weighted matrix of the control input.

6. A control system for a blowroom process of a papermaking felt according to claim 1, characterized in that: The control module optimizes the control input within a future period of time through a predictive control model. Specifically, the predictive control model is: The constraints of the predictive control model are: in, It represents the derivative of the state variable x(τ) with respect to time τ, which represents the rate of change of the state variable over time. x(t) represents the state variable at the current time t. x0 represents the initial state, which represents the initial value of the state variable at the current time t.

7. A control system for the blowroom process of papermaking felts according to claim 1, characterized in that: The data acquisition module communicates with the central control module via CAN bus.

8. The control system for the blowroom process of papermaking felt according to claim 1, characterized in that: The control module uses the output equation y(t)=h(x(t)) to calculate the current fiber density, moisture, temperature and impurity content to monitor the output; Compare the output y(t) with the expected reference output y ref To compare the target state: Using a predictive control model to optimize control inputs over a future period of time by minimizing a cost function that takes into account the error in the state (i.e., the difference from the target state) and the cost of the control input; Based on the minimization of the dynamic equations and the cost function, the optimal control input u(t) is calculated. Specifically, the system will optimize the control input under the constraints for each time step τ. The control input includes roller speed, spacing, cylinder speed and angle.

9. A control system for a blowroom process of a papermaking felt according to claim 1, characterized in that: include: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the cleaning process control system for papermaking felts as described in any one of claims 1 to 8.

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