Tension control device with EtherCAT

Abstract

The invention relates to the technical field of tension control, in particular to a tension control device with EtherCAT. The device comprises a controller, a tension sensor, a signal acquisition circuit, a PID regulator, an execution mechanism, an EtherCAT communication interface and a power supply module. Wherein the signal acquisition circuit comprises a TVS tube protection circuit, a signal amplification circuit, a bias compensation circuit, an RC filter circuit, a single-end-to-double-end circuit and an A / D conversion circuit, and the stability and the accuracy of signals are ensured. High-speed and real-time data transmission and accurate synchronous control are achieved through the EtherCAT communication interface, the whole system can efficiently and accurately monitor and adjust tension, and therefore production efficiency and product quality are improved.

Description

Technical Field

[0001] The present application relates to the technical field of tension control, and in particular to a tension control device with EtherCAT. Background Art

[0002] In the process of modern industrial automation control production, tension control has gradually become an indispensable component in the textile, printing, lithium battery, cable manufacturing and other industries. The tension control device is responsible for high-speed and accurate acquisition of real-time tension and output signals to control the execution of components such as floating rollers, magnetic powder, and variable frequency motors to ensure that the equipment as a whole maintains constant tension operation, thereby ensuring that the material after winding and unwinding is neat and uniform. With the development of society and the continuous innovation of technology, the tension control device requires higher and higher precision and stability at the same time to meet the existing intelligent and automated production needs.

[0003] Traditional tension control devices usually use analog signal transmission. The collected tension sensor signal is converted into a voltage or current signal in equal proportion and sent to the PLC main controller. The main controller determines whether the closed-loop PID meets the requirements by obtaining the real-time fluctuation of the tension sensor. Similarly, traditional tension control devices generally have RS485 communication, which is also used to obtain the real-time fluctuation of the tension sensor. The analog signal transmission method has problems such as signal attenuation over long distances, susceptibility to interference, and wiring troubles; RS485 communication has problems such as slow communication rate and lack of error detection mechanism. EtherCAT, as a high-performance real-time industrial Ethernet protocol, has the advantages of high speed, high precision, and high synchronization. Applying it to the design of tension control devices can effectively overcome the shortcomings of traditional control devices in terms of speed difference and low precision. Summary of the invention

[0004] In order to overcome the above technical problems, the present application provides a tension control device with EtherCAT.

[0005] The tension control device with EtherCAT provided in this application adopts the following technical solution: A tension control device with EtherCAT, comprising: Controller; Tension sensor; A signal acquisition circuit, used for acquiring a differential signal output by the tension sensor; A PID regulator is used to compare the collected differential signal with the preset target tension and generate a control signal; The actuator receives the control signal output by the PID regulator and adjusts the tension; EtherCAT communication interface for high-speed, real-time data transmission and precise synchronization control; The power module uses the isolated power module UWF1209S-1WR3 from Goldensun to power the sensor and the chip at the isolation end. The master station PLC is connected to the EtherCAT communication interface via an Ethernet cable to monitor tension data in real time and send control instructions.

[0006] By adopting the above technical solutions, the tension control device can achieve high-speed, real-time data transmission and precise synchronous control. The EtherCAT communication interface not only improves the system's response speed and the reliability of data transmission, but also simplifies the system wiring and reduces installation and maintenance costs. The power module adopts an isolated power supply design to ensure the electrical safety and stability of the system. Overall, the device significantly improves the accuracy and stability of tension control and is suitable for high-precision tension control requirements in various complex industrial environments.

[0007] Preferably, the signal acquisition circuit comprises: TVS tube protection circuit, used for over-current, over-voltage protection and current limiting of input signals; A signal amplification circuit for suppressing common-mode signals and converting double-ended signals into single-ended signals; The bias compensation circuit is used to increase the input signal to a range suitable for the ADC chip to read; RC filter circuit, used to eliminate high-frequency noise; A single-ended to double-ended circuit is used to convert a single-ended signal into a differential signal; A / D conversion circuit, used for converting analog signals into digital signals; Isolation circuit, used to isolate digital signals to prevent external interference.

[0008] By adopting the above technical solutions, the TVS tube protection circuit in the signal acquisition circuit can effectively prevent the influence of external transient high-voltage shock on the subsequent circuit. The signal amplification circuit can not only suppress the common-mode signal but also convert the double-ended signal into a single-ended signal, thereby improving the quality and stability of the signal. The bias compensation circuit ensures that the input signal is within the reading range of the ADC chip, and the RC filter circuit eliminates high-frequency noise and enhances the purity of the signal. The single-ended to double-ended circuit converts the single-ended signal into a differential signal, further improving the anti-interference ability of the signal. The A / D conversion circuit converts the analog signal into a digital signal with high precision, and the isolation circuit ensures the safety and reliability of the digital signal during the transmission process, thereby improving the measurement accuracy and stability of the tension control device as a whole.

[0009] Preferably, the TVS tube protection circuit includes a transient voltage suppression diode D8, which is used to protect the back-end circuit when the circuit is subjected to transient high voltage impact.

[0010] By adopting the above technical solution, the transient voltage suppression diode D8 in the TVS tube protection circuit can be quickly turned on when the circuit is subjected to transient high voltage impact, absorbing excessive voltage, thereby protecting the subsequent signal processing circuit from damage and ensuring the stability and reliability of the system.

[0011] Preferably, the signal amplification circuit adopts an instrument amplifier AD623, configured with a resistor R35=1.2KΩ, and an amplification factor of 84.5 times. The input end of the instrument amplifier AD623 is connected to the output end of the TVS tube protection circuit, and the output end is connected to the input end of the bias compensation circuit.

[0012] By adopting the above technical solutions, the use of instrument amplifier AD623 not only improves the signal amplification factor and enhances the signal strength, but also effectively suppresses the common mode signal and reduces interference. The configuration resistor R35 = 1.2KΩ makes the amplification factor reach 84.5 times, ensuring the effective amplification of weak differential signals and improving the quality and reliability of signals. The series design of TVS tube protection circuit and signal amplifier circuit can perform overcurrent, overvoltage protection and current limiting on the input signal at the front end to ensure the safe operation of subsequent circuits. The introduction of bias compensation circuit enables the amplified signal to be effectively read by the ADC chip, further improving the accuracy of signal processing. These measures work together to significantly improve the measurement accuracy and stability of the tension control device, thereby better meeting the high-precision requirements in the field of industrial automation.

[0013] Preferably, the bias compensation circuit applies a voltage of 0.82V through voltage-dividing resistors R62 and R61 to compensate for negative voltage input, and the output end of the bias compensation circuit is connected to the input end of the RC filter circuit.

[0014] By adopting the above technical solution, the bias compensation circuit applies a 0.82V voltage through the voltage divider resistors R62 and R61 to compensate for the negative voltage input, ensuring that the A / D chip can correctly read the signal, thereby improving the accuracy and reliability of signal acquisition. At the same time, the output end of the bias compensation circuit is connected to the input end of the RC filter circuit, further eliminating high-frequency noise and enhancing the stability and anti-interference ability of the signal.

[0015] Preferably, the RC filter circuit is composed of an RC filter circuit composed of a resistor R37 and a capacitor C38, and the output end of the RC filter circuit is connected to the input end of the single-ended to dual-ended circuit.

[0016] By adopting the above technical solution, the RC filter circuit can effectively eliminate high-frequency noise and improve the purity and stability of the signal. The RC filter circuit introduces low-pass filtering characteristics into the signal path, ensuring that the collected tension sensor signal will not be affected by high-frequency interference during subsequent processing, thereby improving the measurement accuracy and reliability of the overall system.

[0017] Preferably, the A / D conversion circuit adopts a high-precision 16-bit analog acquisition chip ADS8866, the input end of the A / D conversion circuit is connected to the output end of the single-ended to dual-ended circuit, and the output end is connected to the input end of the isolation circuit.

[0018] By adopting the above technical solution, the high-precision 16-bit analog acquisition chip ADS8866 can convert the differential signal processed by the single-end to double-end circuit into a digital signal. This process ensures the high resolution and accuracy of the tension sensor signal, thereby improving the accuracy of tension control. At the same time, the high-precision characteristics of ADS8866 help reduce measurement errors, allowing the controller to perform PID adjustments more accurately, thereby achieving more stable tension control.

[0019] Preferably, the isolation circuit adopts a four-channel high-speed digital isolation chip CA-IS3741HW, and the output end of the isolation circuit is connected to the input end of the controller.

[0020] By adopting the above technical solutions, the four-channel high-speed digital isolation chip CA-IS3741HW can effectively isolate digital signals, prevent external interference from affecting the internal circuit, and ensure the transmission quality and stability of digital signals. At the same time, the use of this isolation chip also improves the safety and reliability of the system, reduces the misoperation and data loss caused by external interference, and thus ensures the normal operation of the tension control device in a complex industrial environment.

[0021] Preferably, the actuator is a variable frequency motor or a magnetic powder brake, which is used to adjust the tension, and the control end of the actuator is connected to the output end of the PID regulator.

[0022] By adopting the above technical solution, the variable frequency motor or magnetic powder brake can be used as the actuator to accurately adjust the tension according to the control signal output by the PID regulator to ensure constant tension during the entire winding and unwinding process. This design not only improves the accuracy and stability of tension control, but also effectively responds to dynamically changing working conditions, improving production efficiency and product quality.

[0023] Preferably, the master station PLC is connected to the EtherCAT communication interface via an Ethernet cable, so as to monitor the tension data in real time and send control instructions.

[0024] By adopting the above technical solutions, the master station PLC can achieve real-time, high-speed data transmission and precise synchronous control through Ethernet cable and EtherCAT communication interface. This design not only improves the response speed and accuracy of the tension control system, but also monitors the tension data in real time and sends control instructions without increasing the burden on the controller, thereby ensuring that the entire winding and unwinding process always maintains constant tension, significantly improving production efficiency and product quality. At the same time, EtherCAT's high bandwidth characteristics and powerful diagnostic functions enable the system to operate stably in complex industrial environments, reducing maintenance costs and downtime.

[0025] In summary, the present application includes at least one of the following beneficial technical effects: 1. By integrating the EtherCAT communication interface, high-speed, real-time data transmission and precise synchronous control are achieved, which effectively solves the problems of low communication rate and poor anti-interference ability in traditional tension control devices, and significantly improves the real-time performance and stability of the system; 2. The high-voltage isolation processing and multi-stage filtering design in the tension sensor signal acquisition circuit ensures high accuracy and high reliability of the signal, eliminates the influence of high-frequency noise and external electromagnetic interference, and enhances the robustness of the system; 3. The master station PLC is connected to the EtherCAT communication interface via an Ethernet cable to monitor tension data in real time and send control instructions, so that the system can quickly respond to tension changes and adjust PID parameters or target tension in time, further improving the stability and efficiency of tension control. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a circuit block diagram of the overall hardware design of an embodiment of the present application.

[0027] Figure 2 This is the flow chart of the EtherCAT communication involved in PID closed-loop control in this application.

[0028] Figure 3 It is a schematic diagram of the sensor signal acquisition circuit of the embodiment and a conditioning flow chart.

[0029] Figure 4 1 is a flowchart of the EtherCAT protocol of an embodiment. DETAILED DESCRIPTION

[0030] The following is combined with Figure 1-Figure 4 This application is described in further detail.

[0031] Embodiment 1: Reference Figure 1 and Figure 2The embodiment of the present application provides a tension control device with EtherCAT, including a controller, a tension sensor, a signal acquisition circuit, a PID regulator, an actuator, an EtherCAT communication interface and a power module. The controller uses the high-performance single-chip microcomputer STM32F407 of STMicroelectronics as the core, and expands many commonly used general optocoupler inputs, relay outputs, and analog voltage / current outputs in industry. On the industrial communication bus, the controller not only has the RS485 bus of the traditional tension control device, but also adds an industrial high-speed and high-stability EtherCAT control bus.

[0032] Reference Figure 3 The controller in this application is based on STMicroelectronics' high-performance single-chip STM32F407 as the core, and has many commonly used general-purpose optocoupler inputs, relay outputs, and analog voltage / circuit outputs in industry.

[0033] The signal acquisition circuit is mainly used to collect the differential signal output by the tension sensor. Specifically, the signal acquisition circuit includes the following parts: TVS tube protection circuit: TVS tube protection circuit is used to protect input signals from overcurrent, overvoltage and current limiting. For example, transient voltage suppression diode D8 can be used, which can protect the back-end circuit when the circuit is subjected to transient high voltage shock. Alternative solutions can be to use other types of transient protection devices, such as TVS diodes or Zener diodes.

[0034] Signal amplifier circuit: The signal amplifier circuit is used to suppress the common-mode signal and convert the double-ended signal into a single-ended signal. For example, the instrumentation amplifier AD623 can be used, and the configuration resistor R35 = 1.2KΩ, and the amplification factor is 84.5 times. The input of AD623 is connected to the output of the TVS tube protection circuit, and the output is connected to the input of the bias compensation circuit. An alternative solution may be to use other types of high-gain operational amplifiers, such as INA128 or OPA177.

[0035] Bias compensation circuit: The bias compensation circuit applies 0.82V voltage through the voltage divider resistors R62 and R61 to compensate for negative voltage input. This ensures that the ADC chip does not receive negative voltage signals. The output of the bias compensation circuit is connected to the input of the RC filter circuit. An alternative solution could be to use other types of bias circuits such as a voltage follower or a reference voltage source.

[0036] RC filter circuit: The RC filter circuit is used to eliminate high frequency noise. For example, it can be composed of an RC filter circuit consisting of a resistor R37 and a capacitor C38. The output of the RC filter circuit is connected to the input of the single-ended to double-ended circuit. An alternative solution could be to use other types of filters, such as LC filters or multi-stage RC filters.

[0037] Single-ended to dual-ended circuit: The single-ended to dual-ended circuit is used to convert a single-ended signal to a differential signal. For example, the single-ended to differential chip AD8138 can be used. An alternative could be to use other types of differential amplifiers, such as the LT1990 or LMH6611.

[0038] A / D conversion circuit: The A / D conversion circuit is used to convert analog signals into digital signals. For example, the high-precision 16-bit analog acquisition chip ADS8866 can be used. The input end of the A / D conversion circuit is connected to the output end of the single-ended to dual-ended circuit, and the output end is connected to the input end of the isolation circuit. An alternative solution may be to use other types of high-precision A / D converters, such as ADS1256 or LTC2400.

[0039] Isolation circuit: The isolation circuit is used to isolate the digital signal to prevent external interference. For example, the four-channel high-speed digital isolation chip CA-IS3741HW can be used. The output of the isolation circuit is connected to the input of the controller. An alternative could be to use other types of digital isolators, such as the ISO72xx series or ADM2486.

[0040] The PID regulator is used to compare the collected differential signal with the preset target tension and generate a control signal. The controller integrates a PID algorithm, which can adjust the deviation between the actual tension value and the target tension value to generate the corresponding control signal. These control signals will be sent to the actuator to adjust the tension.

[0041] The actuator receives the control signal output by the PID regulator to adjust the tension. The actuator can be a variable frequency motor or a magnetic powder brake. The variable frequency motor can adjust the tension by adjusting the motor speed, while the magnetic powder brake adjusts the tension by changing the magnetic field strength. Both actuators can be selected and used according to actual conditions.

[0042] The power module uses the isolated power module UWF1209S-1WR3 from Golden Sun, and the generated isolated power is responsible for powering the sensor and the chip at the isolated end. The power module provides a stable DC power supply to ensure the reliable operation of the entire system. An alternative solution could be to use isolated power modules from other brands, such as TDK-Lambda or MEAN WELL.

[0043] Specifically, when the sensor is subjected to external force, a weak mV signal will be generated between the two signal lines. The electrical signal first passes through the D8 transient voltage suppression diode, which can protect the back-end circuit when the circuit is subjected to transient high voltage shock. After the signal is transmitted to the U8 instrument amplifier AD623, it will be amplified and then output. The configuration resistor R35 = 1.2KΩ means that this will amplify the signal by 84.5 times. Because the A / D chip cannot recognize negative signals, it is necessary to apply a 0.82V voltage to the bias compensation pin of the AD623 through the voltage divider resistors R62 and R61 to compensate for a negative voltage input. At this point, it can be inferred that when the pressure sensor is in the no-load state, that is, when there is no pressure difference between the two output signal lines, AD623 outputs 0.82V. Combined with the amplification factor, the signal amplified by the instrument amplifier AD623 will enter the RC filter circuit composed of R37 and C38, filter out some high-frequency interference, and then enter the single-ended to differential chip AD8138. The generated differential signal is directly given to the high-precision 16-bit analog acquisition chip ADS8866, which converts the analog signal into a digital signal. Finally, the signal is isolated through the U20 four-channel high-speed digital isolation chip CA-IS3741HW to ensure that the digital signal is not subject to external interference during transmission.

[0044] In addition, the input millivolt signal range that can be collected by the collection circuit in this application is as follows: enter -9.7mV 0mV 10mV 20mV 29.3mV Output 0V 0.82V 1.665V 2.510V 3.3V Therefore, after obtaining the real-time value of the tension sensor, the tension control device compares it with the set target tension and then adjusts the output through its own PID regulator to give it to the signal inverter / magnetic powder to ensure constant tension operation. While the controller is making adjustments, the host PLC can also obtain the current tension value in real time through the EtherCAT industrial bus, and can also fine-tune the target tension and PID parameters of the tension control device in real time, which not only achieves stable control of the tension, reduces tension fluctuations, but also improves tension control efficiency.

[0045] On the other hand, the EtherCAT communication interface is used to achieve high-speed, real-time data transmission and precise synchronous control. The master station PLC is connected to the EtherCAT communication interface via an Ethernet cable to monitor tension data in real time and send control instructions. The EtherCAT protocol has the characteristics of high speed, low latency and high utilization, which can effectively overcome the shortcomings of speed difference and low precision of traditional control devices. The master station PLC can obtain the current tension value in real time through the EtherCAT interface, and fine-tune the target tension and PID parameters of the tension control device, thereby achieving stable control of the tension.

[0046] Reference Figure 4, where the EtherCAT slave application layer operation process, as shown in the figure, the application layer software design part is mainly used to implement the application layer functions of the EtherCAT slave, including slave interface control initialization, EtherCAT function module initialization and main application cycle, where EtherCAT function module initialization mainly refers to the initialization of EtherCAT status, i.e., mailbox, emergency message and COE dictionary. After completing the initial tasks of each interface and function module, the slave enters "OP" and starts to execute the control instructions and local applications sent by the master to the slave.

[0047] The implementation principle of this embodiment is: through the precise acquisition and processing of the tension sensor signal, combined with the high-speed, real-time data transmission capability of the EtherCAT communication interface, the stable control of the tension is achieved. At the same time, through the real-time monitoring and adjustment of the master station PLC, the accuracy and efficiency of the tension control are further improved. This device not only improves the real-time and reliability of the tension control system, but also simplifies the system wiring and reduces the maintenance cost. It is suitable for various high-precision and high-reliability industrial application scenarios.

[0048] Embodiment 2: The difference between this embodiment and the above-mentioned embodiment is that in this embodiment, in order to further improve the robustness and adaptability of the system, a redundant design and an adaptive PID control strategy are introduced.

[0049] Redundant design: In order to improve the reliability of the system, redundant design is added in this embodiment. Specifically, backup units can be set in key components such as tension sensors, controllers, EtherCAT communication interfaces, etc. For example, two tension sensors can be used, one as the main one and the other as the backup one. When the main sensor fails, the backup sensor immediately takes over the work to ensure the normal operation of the system. Similarly, the controller and EtherCAT communication interface can also adopt similar redundant designs to improve the overall reliability of the system.

[0050] Adaptive PID control strategy In order to further improve the control accuracy and adaptability, an adaptive PID control strategy is adopted in this embodiment. Traditional PID control parameters need to be manually adjusted, which is a cumbersome process and has poor results. The adaptive PID control strategy can better adapt to different working conditions by online learning and adjusting PID parameters. Specifically, a machine learning algorithm can be integrated into the controller to dynamically adjust the PID parameters by collecting and analyzing tension data in real time to achieve the optimal control effect.

[0051] The details are as follows: 1. Data acquisition and storage: The controller collects tension data in real time through the EtherCAT interface and stores it in the memory.

[0052] 2. Data analysis: The controller’s built-in data analysis module will process the collected tension data and extract characteristic values, such as maximum, minimum, average, etc.

[0053] 3. Model training: Based on the extracted feature values, the controller uses machine learning algorithms (such as neural networks, support vector machines, etc.) to establish a prediction model to predict future tension change trends.

[0054] 4. Parameter adjustment: According to the prediction results, the controller automatically adjusts the PID parameters to achieve better control effect.

[0055] The implementation principle of this embodiment is: by introducing redundant design and adaptive PID control strategy, this embodiment not only improves the reliability of the system, but also dynamically adjusts the control parameters according to different working conditions to achieve more precise tension control. This enables the system to maintain good performance and stability in the face of complex and changing working environments.

[0056] Embodiment 3: The difference between this embodiment and the above-mentioned embodiment is that in this embodiment, in order to further improve the flexibility and scalability of the system, modular design and integration of programmable logic controller (PLC) are introduced.

[0057] Modular design In order to improve the flexibility and scalability of the system, a modular design is adopted in this embodiment. Specifically, the tension control device can be divided into multiple functional modules, each of which has independent functions and interfaces. For example, the signal acquisition circuit, PID regulator, actuator, EtherCAT communication interface, etc. can be designed as independent modules. Such a design makes the system easier to maintain and upgrade, and also facilitates the customization requirements in different application scenarios.

[0058] Specifically, 1. Signal acquisition module: responsible for collecting the differential signal of the tension sensor and connecting with other modules through a standardized interface.

[0059] 2.PID control module: responsible for comparing the collected differential signal with the preset target tension and generating a control signal.

[0060] 3. Actuator module: receives the control signal output by the PID regulator and adjusts the tension.

[0061] 4. Communication module: responsible for achieving high-speed, real-time data transmission and precise synchronization control. 5. Power module: provides stable power supply for each module.

[0062] Integration of Programmable Logic Controller (PLC) In order to further enhance the intelligent level of the system, a programmable logic controller (PLC) is integrated in this embodiment. PLC can not only realize the basic control function of the tension control device, but also realize more complex control logic through programming. For example, a program can be written to realize functions such as multi-stage tension control and temperature compensation.

[0063] Specifically, 1.PLC programming: Use ladder diagram or other programming languages ​​to write control programs to achieve advanced control functions of the tension control device.

[0064] 2. Communication interface: PLC is connected to EtherCAT communication interface via Ethernet cable to achieve real-time data exchange.

[0065] 3. Human-machine interface: Through human-machine interface devices such as touch screen, users can easily view and adjust tension control parameters.

[0066] The implementation principle of this embodiment is: through modular design and PLC integration, this embodiment not only improves the flexibility and scalability of the system, but also realizes more complex control logic to meet the needs of different application scenarios. This design makes the system more intelligent and efficient, which helps to improve production efficiency and product quality.

[0067] Embodiment 4: The difference between this embodiment and the above-mentioned embodiment is that in this embodiment, in order to further improve the anti-interference ability and stability of the system, multiple protection measures and self-checking mechanisms are introduced.

[0068] Multiple protection measures In order to improve the anti-interference ability of the system, multiple protection measures are taken in this embodiment. Specifically, in addition to the TVS tube protection circuit, a series of protection measures are added to the signal transmission path, such as EMI filters, surge protectors, etc. In addition, shielded cables and grounding technology are also used to further reduce the impact of external interference.

[0069] in, 1.EMI filter: Add EMI filter in the signal transmission path to filter out high-frequency electromagnetic interference.

[0070] 2. Surge protector: Add surge protectors to the power input and signal input to prevent damage caused by lightning strikes and other sudden voltage fluctuations.

[0071] 3. Shielded cable: Use shielded cable to connect each module to reduce the impact of external electromagnetic interference.

[0072] 4. Grounding technology: Rationally design the grounding system to ensure that the ground wires of all modules are well connected and reduce interference between ground wires.

[0073] In addition, in order to improve the stability of the system, a self-check mechanism is introduced in this embodiment. The self-check mechanism can check the status of each module when the system is started or regularly, and timely discover and report potential faults. Specifically, a self-check program can be integrated in the controller to regularly check key indicators of sensors, controllers, communication interfaces, etc., such as voltage, current, temperature, etc.

[0074] Specific: 1. Self-test program: Write a self-test program in the controller to regularly check the status of each module.

[0075] 2. Fault alarm: Once an abnormal situation is detected, the fault information will be immediately reported to the master station PLC and an alarm will be triggered.

[0076] 3. Log Recording: Record the results of each self-test in a log file to facilitate subsequent analysis and maintenance.

[0077] The implementation principle of this embodiment is: by introducing multiple protection measures and self-checking mechanisms, this embodiment not only improves the anti-interference ability and stability of the system, but also can timely discover and handle potential faults, reducing system downtime and maintenance costs. This design scheme enables the system to maintain reliable operation in harsh industrial environments.

[0078] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A tension control device with EtherCAT, characterized in that: include: Controller; Tension sensor; A signal acquisition circuit, used for acquiring a differential signal output by the tension sensor; A PID regulator is used to compare the collected differential signal with the preset target tension and generate a control signal; The actuator receives the control signal output by the PID regulator and adjusts the tension; EtherCAT communication interface for high-speed, real-time data transmission and precise synchronization control; The power module uses the isolated power module UWF1209S-1WR3 from Mornsun to power the sensor and the chip at the isolation end. The master station PLC is connected to the EtherCAT communication interface via an Ethernet cable to monitor the tension data in real time and send control instructions.

2. A tension control device with EtherCAT according to claim 1, characterized in that: The signal acquisition circuit comprises: TVS tube protection circuit, used for over-current, over-voltage protection and current limiting of input signals; A signal amplification circuit for suppressing common-mode signals and converting double-ended signals into single-ended signals; The bias compensation circuit is used to increase the input signal to a range suitable for the ADC chip to read; RC filter circuit, used to eliminate high-frequency noise; A single-ended to double-ended circuit is used to convert a single-ended signal into a differential signal; A / D conversion circuit, used for converting analog signals into digital signals; Isolation circuit, used to isolate digital signals to prevent external interference; The input and output ends of the TVS tube protection circuit, the signal amplification circuit, the bias compensation circuit, the RC filter circuit, the single-end to double-end circuit, the A / D conversion circuit and the isolation circuit are connected in sequence.

3. A tension control device with EtherCAT according to claim 2, characterized in that: The TVS tube protection circuit includes a transient voltage suppression diode D8, which is used to protect the back-end circuit when the circuit is subjected to transient high voltage impact.

4. A tension control device with EtherCAT according to claim 2, characterized in that: The signal amplification circuit adopts an instrument amplifier AD623, configured with a resistor R35=1.2KΩ, and an amplification factor of 84.5 times. The input end of the instrument amplifier AD623 is connected to the output end of the TVS tube protection circuit, and the output end is connected to the input end of the bias compensation circuit.

5. A tension control device with EtherCAT according to claim 2, characterized in that: The bias compensation circuit applies a voltage of 0.82V through the voltage-dividing resistors R62 and R61 to compensate for the negative voltage input, and the output end of the bias compensation circuit is connected to the input end of the RC filter circuit.

6. A tension control device with EtherCAT according to claim 2, characterized in that: The RC filter circuit is composed of a resistor R37 and a capacitor C38, and the output end of the RC filter circuit is connected to the input end of the single-end to double-end circuit.

7. A tension control device with EtherCAT according to claim 2, characterized in that: The A / D conversion circuit adopts a high-precision 16-bit analog acquisition chip ADS8866. The input end of the A / D conversion circuit is connected to the output end of the single-end to dual-end circuit, and the output end is connected to the input end of the isolation circuit.

8. A tension control device with EtherCAT according to claim 2, characterized in that: The isolation circuit adopts a four-channel high-speed digital isolation chip CA-IS3741HW, and the output end of the isolation circuit is connected to the input end of the controller.

9. A tension control device with EtherCAT according to claim 1, characterized in that: The actuator is a variable frequency motor or a magnetic powder brake, which is used to adjust the tension, and the control end of the actuator is connected to the output end of the PID regulator.

10. A tension control device with EtherCAT according to claim 1, characterized in that: The master station PLC is connected to the EtherCAT communication interface via an Ethernet cable to monitor tension data in real time and send control instructions.

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