Eddy current sensor and swing frame static automatic calibration measurement and control system and method

Abstract

The embodiment of the invention provides an eddy current sensor and swing frame static automatic calibration measurement and control system and method.The measurement and control system is connected with an eddy current sensor and swing frame static automatic calibration device and comprises a TFT touch screen module, a measurement module, a communication module, a motion control module and a power module, and the modules are controlled through a single-chip microcomputer; the TFT touch screen module comprises a TFT touch screen and is used for receiving input information and displaying process data and curves of automatic calibration; the measurement module is used for realizing linear displacement measurement and measuring the output voltage of the current vortex sensor proximitor; the communication module is used for enabling the STM32 single-chip microcomputer to communicate with the TFT touch screen and the storage medium to realize data transmission; the motion control module is used for controlling the operation of the stepping motor; the power supply module is used for supplying power to the system and external equipment.

Description

Technical Field

[0001] This document relates to the field of measurement and control technology, and in particular to an eddy current sensor and a static automatic calibration measurement and control system and method for a pendulum frame. Background Technology

[0002] Over long-term use, eddy current sensors may exhibit significant errors or inaccuracies in their readings due to aging or environmental influences. Furthermore, measurement devices for shaft displacement and rotor-cylinder expansion differential in 300MW and above steam turbine generator units utilize a combination of a pendulum frame and eddy current sensors. Because the calibration process is complex and the calibration results directly impact the accuracy of unit measurements and operational safety, regular calibration is necessary to promptly identify and address any issues with the eddy current sensors or pendulum frames, ensuring the accuracy of their measurement results.

[0003] Currently, the calibration of eddy current sensors and pendulum devices in China requires manual adjustment of displacement, manual reading, manual recording of data, and manual analysis of data. Each measurement of an eddy current sensor or pendulum takes about 3 hours, and long working hours can easily lead to errors in data reading and recording. Summary of the Invention

[0004] This specification provides one or more embodiments of a static automatic calibration and control system for an eddy current sensor and a pendulum frame. Connecting to a static automatic calibration device for the eddy current sensor and pendulum frame, the control system includes a TFT touchscreen module, a measurement module, a communication module, a motion control module, and a power supply module. An STM32 microcontroller controls the TFT touchscreen module, measurement module, communication module, motion control module, and power supply module. The TFT touchscreen module displays the type of the eddy current sensor and pendulum frame, receives user input, and displays the automatic calibration process data and curves to the user. The measurement module measures linear displacement by measuring the rotation angle of a stepper motor and measures the output voltage of the eddy current sensor preamplifier. The communication module includes TFT touchscreen communication and storage communication. TFT touchscreen communication facilitates communication between the STM32 microcontroller and the TFT touchscreen, enabling user interaction with the STM32 microcontroller. Storage communication facilitates data transmission between the STM32 microcontroller and a storage medium. The motion control module controls the operation of the stepper motor based on the information received from the TFT touchscreen module. The power supply module provides power to the system and external devices.

[0005] Furthermore, the user input information received by the TFT touchscreen module includes "zero" point input, sensor selection information, and manual jog control information.

[0006] Furthermore, the measurement module is specifically used for:

[0007] Displacement measurement: Displacement is measured by measuring the rotation angle of the stepper motor;

[0008] Voltage measurement of the sensor preamplifier: The analog signal to digital signal module is used to collect the analog signal of the sensor and convert it into a 16-bit digital signal. When the moving part moves to a certain position, the motion control module automatically reads the 16-bit voltage value data of the analog signal to digital signal to complete the voltage measurement of the sensor preamplifier.

[0009] Furthermore, the specific method for measuring displacement by measuring the rotation angle of a stepper motor is as follows:

[0010] An optical encoder with 1000 lines / revolution and a rotational angle resolution of 0.36° is used, and the angular displacement parameter of the integrated slide table is 5mm / rad to realize displacement measurement and control.

[0011] Furthermore, when the communication module communicates with the TFT touch screen, it uses a serial asynchronous transceiver interface to complete the communication function with the touch screen.

[0012] Furthermore, the communication module is specifically used for:

[0013] Upon receiving a command from the touchscreen, the system sequentially receives data from the host computer in frames of 8 bits each.

[0014] Secondly, after receiving all the data, the segmented data frames are stored in the circular buffer pool.

[0015] Finally, the parsed instructions and data are used to control the operation of other modules;

[0016] When data needs to be returned to the touchscreen, the received processed displacement and voltage signal data are sent to the TFT touchscreen in segments for display.

[0017] Furthermore, the communication module also includes storage communication, used for:

[0018] To enable communication between the two devices, the system configures both devices in terms of storage device initialization, communication protocol stack implementation, and data transmission.

[0019] Furthermore, the motion control module is specifically used to: transmit the control commands of the TFT touch screen to the motion control module via the serial port through the communication module; the motion control module generates pulse signals of a certain frequency and stepper motor movement direction signals according to the commands, and sends them to the stepper motor driver through subsequent hardware circuits to control the stepper motor to run.

[0020] Furthermore, the power module is specifically used for:

[0021] The stepper motor is directly powered by a 24V DC power supply.

[0022] A DC voltage regulator circuit is used to step down the DC 24V power supply to a DC 5V power supply to power the measurement and control system.

[0023] A 24V DC power supply is used to power the preamplifier of the eddy current sensor.

[0024] This specification provides one or more embodiments of a static automatic calibration and control method for an eddy current sensor and a pendulum frame, including:

[0025] Users can set the inherent parameters of the eddy current sensor on the TFT touchscreen screen according to the technical specifications of the eddy current sensor.

[0026] Generate and send corresponding instructions to the microcontroller measurement and control system via serial port based on the parameter settings on the interface;

[0027] The microcontroller-based measurement and control system generates corresponding commands based on instructions to control the movement of the stepper motor and mechanical parts, and collects displacement data and eddy current sensor signal data.

[0028] The collected data is then processed, and the calibration results are displayed on a TFT touchscreen, completing the entire automatic calibration process.

[0029] Using the embodiments of the present invention, various specifications of eddy current sensors can be calibrated individually, and pendulum frames can also be calibrated. The operation is simple, which reduces the threshold for calibration personnel and labor costs, and improves the calibration accuracy of eddy current sensors and pendulum frames.

[0030] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in one or more embodiments of this specification or in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1This is a schematic diagram illustrating the composition of an eddy current sensor and a pendulum static automatic calibration and control system provided for one or more embodiments of this specification. Detailed Implementation

[0033] To enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this document.

[0034] System Implementation Examples

[0035] According to embodiments of the present invention, an eddy current sensor and a pendulum static automatic calibration and control system are provided. Figure 1 This is a schematic diagram illustrating the composition of an eddy current sensor and a pendulum static automatic calibration and control system provided in one or more embodiments of this specification, as shown below. Figure 1 As shown, the eddy current sensor and pendulum static automatic calibration and control system according to an embodiment of the present invention is connected to the eddy current sensor and pendulum static automatic calibration device. The core of the control system adopts an STM32 microcontroller and specifically includes: a TFT touch screen module, a measurement module, a communication module, a motion control module, and a power supply module. The microcontroller controls the TFT touch screen module, the measurement module, the communication module, the motion control module, and the power supply module.

[0036] The TFT touchscreen module includes a TFT touchscreen, which is used to display the eddy current sensor and pendulum type, receive information input by the user, and display the automatic calibration process data and curves to the user.

[0037] Users can easily input zero-point data, select sensors, and perform manual jog control via a simple touchscreen. The user-input data is then sent via serial port to the measurement and control software module within the STM32 microcontroller and stored in the STM32's circular buffer for command parsing. Finally, the touchscreen displays the movement distance and voltage values ​​collected during the verification process uploaded by the STM32, along with the verification results and the resulting curve, providing users with a comprehensive understanding of the sensor or pendulum's verification results.

[0038] The measurement module is used to measure linear displacement by measuring the rotation angle of the stepper motor, and to measure the output voltage of the eddy current sensor preamplifier.

[0039] Displacement measurement is achieved by measuring the rotation angle of a stepper motor. This embodiment uses an optical encoder with 1000 lines / revolution and a rotation angle resolution of 0.36°, combined with the angular displacement parameter of the slide table (5 mm / rad), to achieve displacement measurement and control.

[0040] The STM32 microcontroller automatically acquires and counts the two pulse input signals from the optical encoder and sends the displacement data to the stepper motor control module in real time. The module primarily handles pulse data addition, subtraction, and recording. It also transmits this pulse data to the STM32's PID control algorithm for deviation calculation, forming a complete closed-loop PID precise control of the displacement.

[0041] The analog signal to digital signal module acquires the sensor's analog signal and converts it into a 16-bit digital signal. When the moving part moves to a certain position, the motion control module automatically reads the 16-bit voltage value data converted from the analog signal to the digital signal, thus completing the voltage measurement.

[0042] The eddy current sensor outputs an analog voltage signal of 0 to -24V or 0 to +24V. To measure this voltage value, a three-channel 12-bit analog-to-digital converter module integrated in the STM32 microcontroller (requiring configuration of the corresponding STM32 registers) is used. After the STM32 starts operating, it generates a clock signal and control commands to initiate the analog-to-digital signal sampling process. The module continuously acquires the sensor signal and converts it into a 16-bit digital signal. When the moving part reaches a specific position, the stepper motor control module automatically reads the 16-bit voltage value from the analog-to-digital converter to complete the voltage measurement. Since the analog input of the STM32 microcontroller's analog-to-digital converter module can only receive voltage signals of ±3.3V, voltages exceeding 3.3V will damage the microcontroller core. Therefore, two stages of low-noise high-voltage operational amplifiers are used to reduce the input voltage.

[0043] The communication module includes TFT touch screen communication and storage communication. The TFT touch screen communication is used for communication between the STM32 microcontroller and the TFT touch screen, enabling user interaction with the STM32 microcontroller.

[0044] This embodiment uses a serial asynchronous transceiver interface to complete the communication function with the touch screen. STM and C language are used to implement the various functions of the general serial asynchronous transceiver interface. According to the actual needs of this module, other auxiliary programs can be flexibly added to realize various needs in this module.

[0045] The communication between the TFT touchscreen and the STM32 microcontroller is implemented as follows: First, after receiving a command from the touchscreen, the communication module receives data from the host computer in 8-bit frames. Second, after receiving all the data, the segmented data frames are stored in a circular buffer for later parsing and use of the commands and data sent from the screen. Finally, the parsed commands and data are used to control the operation of other modules. When data needs to be returned to the touchscreen, the stepper motor module sends the processed displacement and voltage signal data to the communication module, simultaneously triggering the communication module to send data to the touchscreen module in segments.

[0046] The storage communication is used for communication between the STM32 and the storage device (USB flash drive) to achieve data transmission. Specifically, the two devices are configured from aspects such as storage device (USB flash drive) initialization, communication protocol stack implementation, and data transmission to achieve communication between the two devices.

[0047] The motion control module is used to control the operation of the stepper motor based on the information received from the TFT touch screen module.

[0048] The motion control module is specifically used for: transmitting the control commands of the touch screen to the stepper motor control module through the serial port via the communication module in the STM32. The stepper motor control module generates a pulse signal of a certain frequency and a stepper motor motion direction signal according to the command, and sends them to the stepper motor driver through subsequent hardware circuits. Finally, the driver controls the motor to run. The system is set with two working modes. (1) Measurement mode: This module will control the motion mechanism to perform reciprocating motion in an orderly manner according to the model of the eddy current sensor or pendulum. When the motor runs to the range of the corresponding eddy current sensor or pendulum, it will automatically stop for 50 milliseconds to facilitate the reading of voltage and displacement signals. After the reading is completed, the motor will continue to run until the motion mechanism has completed three reciprocating ranges; (2) Zeroing mode: The manual jog button of the touch screen can be used to control the motor to run once according to the actual situation on site, so as to adjust the position of the moving parts.

[0049] The power module is used to supply power to the system and external devices.

[0050] In this embodiment, the power supply module is mainly divided into three parts: a DC 24V power supply is used to directly power the stepper motor; a DC voltage regulator and step-down circuit is used to reduce the DC 24V power supply to a high-quality and stable DC 5V power supply for the STM32; and a DC 24V power supply is used to power the peripheral device (eddy current sensor preamplifier).

[0051] Method Implementation Examples

[0052] According to embodiments of the present invention, a static automatic calibration and control method for an eddy current sensor and a pendulum frame is provided. Specifically, the static automatic calibration and control method for an eddy current sensor and a pendulum frame according to embodiments of the present invention includes:

[0053] Users can set the inherent parameters of the eddy current sensor on the TFT touchscreen screen according to the technical specifications of the eddy current sensor.

[0054] Generate and send corresponding instructions to the microcontroller measurement and control system via serial port based on the parameter settings on the interface;

[0055] The microcontroller-based measurement and control system generates corresponding commands based on instructions to control the movement of the stepper motor and mechanical parts, and collects displacement data and eddy current sensor signal data.

[0056] The collected data is then processed, and the calibration results are displayed on a TFT touchscreen, completing the entire automatic calibration process.

[0057] The embodiments of the present invention are method embodiments corresponding to the above method embodiments. The specific operations can be understood by referring to the description of the system embodiments, and will not be repeated here.

[0058] The beneficial effects of this invention are as follows:

[0059] Using the embodiments of the present invention, various specifications of eddy current sensors can be calibrated individually, and pendulum frames can also be calibrated. The operation is simple, which reduces the threshold for calibration personnel and labor costs, and improves the calibration accuracy of eddy current sensors and pendulum frames.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A static automatic calibration and control system for an eddy current sensor and a pendulum frame, comprising an eddy current sensor and a static automatic calibration device for the pendulum frame, characterized in that, The measurement and control system includes a TFT touchscreen module, a measurement module, a communication module, a motion control module, and a power supply module. A microcontroller controls these modules. The TFT touchscreen module displays the eddy current sensor and pendulum type, receives user input, and displays automatic calibration process data and curves. The measurement module measures linear displacement by measuring the stepper motor's rotation angle and the output voltage of the eddy current sensor's preamplifier. The communication module includes TFT touchscreen communication and storage communication. TFT touchscreen communication facilitates communication between the STM32 microcontroller and the TFT touchscreen, enabling user interaction. Storage communication facilitates data transmission between the STM32 microcontroller and a storage medium. The motion control module controls the stepper motor's operation based on information received from the TFT touchscreen module. The power supply module provides power to the system and external devices.

2. The system according to claim 1, characterized in that, The TFT touchscreen module receives user input information including "zero" point input, sensor selection information, and manual jog control information.

3. The system according to claim 1, characterized in that, The measurement module is specifically used for: Displacement measurement: Displacement is measured by measuring the rotation angle of the stepper motor; Voltage measurement of the sensor preamplifier: The analog signal to digital signal module is used to collect the analog signal of the sensor and convert it into a 16-bit digital signal. When the moving part moves to a certain position, the motion control module automatically reads the 16-bit voltage value data of the analog signal to digital signal to complete the voltage measurement of the sensor preamplifier.

4. The system according to claim 3, characterized in that, The specific method for measuring displacement using the rotation angle of a stepper motor is as follows: An optical encoder with 1000 lines / revolution and a rotational angle resolution of 0.36° is used, and the angular displacement parameter of the integrated slide table is 5mm / rad to realize displacement measurement and control.

5. The system according to claim 1, characterized in that, When the communication module communicates with the TFT touch screen, it uses a serial asynchronous transceiver interface to complete the communication function with the touch screen.

6. The system according to claim 5, characterized in that, The communication module is specifically used for: Upon receiving a command from the touchscreen, the system sequentially receives data from the host computer in frames of 8 bits each. Secondly, after receiving all the data, the segmented data frames are stored in the circular buffer pool. Finally, the parsed instructions and data are used to control the operation of other modules; When data needs to be returned to the touchscreen, the received processed displacement and voltage signal data are sent to the TFT touchscreen in segments for display.

7. The system according to claim 1, characterized in that, The storage communication is used to communicate with the storage device. Specifically, the two devices are configured in terms of storage device initialization, communication protocol stack implementation and data transmission to realize communication between the two devices.

8. The system according to claim 1, characterized in that, The motion control module is specifically used to: transmit control commands from the TFT touchscreen to the motion control module via a serial port through the communication module; the motion control module generates pulse signals of a certain frequency and stepper motor movement direction signals according to the commands, and sends them to the stepper motor driver through subsequent hardware circuits to control the stepper motor to run.

9. The system according to claim 1, characterized in that, The power module is specifically used for: The stepper motor is directly powered by a 24V DC power supply. A DC voltage regulator circuit is used to step down the DC 24V power supply to a DC 5V power supply to power the measurement and control system. A 24V DC power supply is used to power the preamplifier of the eddy current sensor.

10. A static automatic calibration and control method for an eddy current sensor and a pendulum frame, characterized in that, include: Users can set the inherent parameters of the eddy current sensor on the TFT touchscreen screen according to the technical specifications of the eddy current sensor. Generate and send corresponding instructions to the microcontroller measurement and control system via serial port based on the parameter settings on the interface; The microcontroller-based measurement and control system generates corresponding commands based on instructions to control the movement of the stepper motor and mechanical parts, and collects displacement data and eddy current sensor signal data. The collected data is then processed, and the calibration results are displayed on a TFT touchscreen, completing the entire automatic calibration process.

Images