A test and control system for a butterfly valve

Abstract

This invention relates to the field of vacuum butterfly valves, specifically disclosing a test and control system for a butterfly valve. The system includes: a frame; an opening calibration module, which includes a host computer electrically connected to the MCU of the vacuum butterfly valve, used to calibrate the actual valve opening of the vacuum butterfly valve to ensure consistency with the input target opening; by calibrating the actual opening of the vacuum butterfly valve with the input target opening through the opening calibration module, the error between the input analog signal and the output rotation angle in the vacuum butterfly valve is minimized, thereby improving the accuracy of the vacuum butterfly valve; the pressure control test module evaluates the pressure control capability of the vacuum butterfly valve to ensure that the pressure control response speed of the vacuum butterfly valve is within a reasonable range, thereby improving the product quality of the vacuum butterfly valve; the diversion connecting pipe can move up and down with the extension and retraction of the cylinder, thereby facilitating quick disassembly and assembly during vacuum butterfly valve testing, thus improving the testing efficiency of the vacuum butterfly valve.

Description

Technical Field

[0001] This invention relates to the field of vacuum butterfly valves, specifically to a test and control system for butterfly valves. Background Technology

[0002] Vacuum butterfly valves are key control components in vacuum systems and are widely used in fields with extremely high vacuum control requirements, such as semiconductor manufacturing, photovoltaics, and aerospace. Their working principle is to change the flow channel diameter by driving the valve plate to rotate, thereby precisely regulating the gas flow rate and system vacuum level in the pipeline. The performance of vacuum butterfly valves, especially the control accuracy of their valve plate opening and the dynamic pressure control response speed, is directly related to the stability of the entire process system and product quality.

[0003] First, due to manufacturing tolerances and component differences, even vacuum butterfly valves produced in the same batch may have nonlinear errors between the received control signal (analog signal) and the actual rotation angle of the valve plate. Currently, manual debugging or simple point-to-point comparison is commonly used, which makes it difficult to systematically calibrate and compensate for the relationship between "input signal and output opening". As a result, the control accuracy of the butterfly valve in actual applications cannot be guaranteed.

[0004] Secondly, existing testing platforms mostly focus on testing static indicators such as valve sealing and ultimate vacuum. However, they lack an automated closed-loop testing system for quantitative evaluation and assessment of key dynamic performance of butterfly valves under varying operating conditions, such as pressure control capability and response speed. This makes it impossible to effectively screen out products with slow response or substandard performance, thus creating potential risks for downstream applications. Summary of the Invention

[0005] The purpose of this invention is to provide a test and control system for butterfly valves, which overcomes the above-mentioned defects in the prior art.

[0006] According to the present invention, a test and control system for a butterfly valve includes:

[0007] frame;

[0008] The opening calibration module includes a host computer that is electrically connected to the MCU of the vacuum butterfly valve and is used to calibrate that the actual opening of the valve plate of the vacuum butterfly valve is consistent with the input target opening.

[0009] The pressure control test module is used to test the pressure control capability of the vacuum butterfly valve after the opening calibration is completed. The pressure control test module specifically includes a test furnace, a vacuum pump and an interface component, and shares a host computer with the opening calibration module.

[0010] The test furnace is fixed on the frame, and a vacuum sensor is installed on the test furnace to detect the vacuum level inside the test furnace.

[0011] The vacuum pump is connected to the test furnace and is used to evacuate the test furnace to a vacuum.

[0012] The interface component includes a main pipe, an angle valve, a first connecting pipe, and a diversion connecting pipe. The main pipe is connected to the test furnace. The on / off state between the main pipe and the first connecting pipe is controlled by the angle valve. The flange of the vacuum butterfly valve is fixed between the lower end of the diversion connecting pipe and the upper end of the first connecting pipe. The upper end of the diversion connecting pipe is connected to the external environment.

[0013] The host computer is electrically connected to the MCU, vacuum sensor, and vacuum pump. It inputs the target vacuum level to the MCU, the vacuum pump evacuates the test furnace to a vacuum, the vacuum sensor acquires the actual vacuum level and sends an analog signal to the host computer, the host computer drives the MCU to control the valve plate to change its opening degree, and records the single response time of the vacuum butterfly valve during the adjustment process. Through closed-loop control, the actual vacuum level is adjusted to approach the target vacuum level. The host computer evaluates the pressure control capability of the vacuum butterfly valve based on the accumulated response time.

[0014] A further technical solution is that the calibration process of the aperture calibration module includes the following steps:

[0015] S1. The host computer sends a series of preset target opening value signals to the MCU of the vacuum butterfly valve;

[0016] S2. For each target opening value signal, the valve plate of the vacuum butterfly valve rotates by the corresponding angle, and the encoder inside the vacuum butterfly valve collects the actual opening value of the valve plate and feeds it back to the host computer via the MCU.

[0017] S3. The host computer calculates the opening difference between the actual opening value and the input target opening value. Based on the opening difference, it generates and sends a control signal to the MCU of the vacuum butterfly valve to drive the valve plate to rotate, thereby reducing the opening difference.

[0018] S4. Iterate through S2-S3 until the opening difference is less than or equal to a preset tolerance threshold.

[0019] In a further technical solution, the host computer generates the control signal based on the opening difference value obtained in step S3 using an incremental PID control algorithm.

[0020] A further technical solution is provided in that an inlet pipe and an outlet pipe are fixed on the periphery of the test furnace. The inlet pipe is connected to the main pipeline through a second connecting pipe, and the outlet pipe is connected to the inlet of the vacuum pump through a third connecting pipe. A motor is provided on one side of the vacuum pump, and the motor is electrically connected to the host computer. The motor is used to drive the vacuum pump to perform vacuuming.

[0021] A further technical solution is that the main pipeline is a pipeline with one end closed and the other end open, the second connecting pipe is connected to the open end of the main pipeline, multiple branch pipes are fixed on the peripheral wall of the main pipeline, multiple angle valves are provided and correspond one-to-one with multiple branch pipes, the air outlet of the angle valve is connected to the branch pipe, multiple first connecting pipes are provided and correspond one-to-one with multiple angle valves, the first connecting pipe is connected to the air inlet of the angle valve, a fixed platform is fixed on the frame, and the first connecting pipe passes through the fixed platform and is fixedly connected to it.

[0022] A further technical solution is provided, wherein multiple support rings are fixed on the fixed platform, the support rings are sleeved on the outer periphery of the first connecting pipe, and multiple circumferentially evenly distributed guide posts are fixed on the support rings. The guide posts penetrate the through holes of the upper flange of the first connecting pipe, and the through holes on the flange of the vacuum butterfly valve correspond one-to-one with the guide posts. When the flange of the vacuum butterfly valve abuts against the first connecting pipe, the guide posts penetrate the through holes of the upper flange.

[0023] A further technical solution is provided, wherein the lower end of the diversion connecting pipe is divided into multiple diversion ends, each diversion end being configured corresponding to the first connecting pipe. When the flange on the diversion end abuts against the flange of the vacuum butterfly valve, the guide post penetrates the through hole of the flange on the diversion end. The upper end of the diversion connecting pipe is configured as an air inlet and connected to the external environment. A lifting plate is fixed between adjacent diversion ends. Multiple cylinders corresponding to the lifting plates are fixed on the lower end face of the fixed platform. The piston rod of the cylinder penetrates upward through the fixed platform and is fixedly connected to the lower end face of the lifting plate. The cylinder is electrically connected to the upper host computer.

[0024] A further technical solution is that the closed-loop control process of the pressure control test module specifically includes:

[0025] SS1. Input the target vacuum level into the MCU via the host computer;

[0026] SS2, The host computer controls the vacuum pump to evacuate the test furnace to a vacuum, and the vacuum sensor continuously detects the actual vacuum level in the test furnace and sends an analog signal to the host computer at a frequency of 10Hz;

[0027] SS3. The host computer calculates the vacuum difference between the actual vacuum level and the target vacuum level and sends it to the MCU;

[0028] SS4 and MCU generate control signals based on the vacuum difference through incremental PID control algorithm to drive the valve plate to rotate, thereby changing the opening of the vacuum butterfly valve. The encoder in the vacuum valve detects the change in valve plate angle and sends the analog signal to the host computer via the MCU. The host computer then records the single response time of the vacuum butterfly valve.

[0029] If the change in the opening degree of the vacuum butterfly valve causes a change in the vacuum degree inside the test furnace, then repeat SS2-SS4 until the actual vacuum degree approaches the target vacuum degree. The host computer evaluates the pressure control capability of the vacuum butterfly valve based on the accumulated response time.

[0030] A further technical solution is that the single response time of the vacuum butterfly valve recorded by the host computer refers to the time elapsed from when the host computer sends a control signal to when it receives the valve plate rotation simulation signal fed back by the MCU.

[0031] The sum of the single response times is the total adjustment time for the actual vacuum level to reach and stabilize within the target vacuum level tolerance range from its initial value. This total adjustment time is used to quantitatively evaluate the pressure control capability and dynamic performance of the vacuum butterfly valve.

[0032] The beneficial effects of this invention are:

[0033] 1. The actual opening degree of the vacuum butterfly valve is calibrated with the input target opening degree through the opening degree calibration module, thereby minimizing the error between the input analog signal and the output rotation angle in the vacuum butterfly valve and improving the accuracy of the vacuum butterfly valve.

[0034] 2. The pressure control capability of the vacuum butterfly valve is evaluated through the pressure control test module to ensure that the pressure control response speed of the vacuum butterfly valve is within a reasonable range, thereby improving the product quality of the vacuum butterfly valve.

[0035] 3. The diversion connecting pipe can move up and down with the extension and retraction of the cylinder, which facilitates quick disassembly and assembly during vacuum butterfly valve testing, thereby improving the testing efficiency of vacuum butterfly valve. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structure of the present invention;

[0037] Figure 2 This is a schematic diagram of the cylinder installation position in this invention;

[0038] Figure 3 This is the present invention. Figure 1 The right view;

[0039] Figure 4 This is a schematic diagram of the vacuum butterfly valve installation in this invention;

[0040] Figure 5 This is a schematic diagram of the system opening calibration process provided by the present invention;

[0041] Figure 6 This is a schematic diagram of the closed-loop control process for system pressure testing provided by the present invention.

[0042] In the picture:

[0043] 10. Frame; 11. Mounting platform; 20. Test furnace; 21. Vacuum sensor; 22. Inlet pipe; 23. Outlet pipe; 30. Second connecting pipe; 31. Third connecting pipe; 32. Diverting pipe; 321. Inlet end; 322. Diverting end; 33. Main pipe; 34. First connecting pipe; 40. Host computer; 50. Vacuum pump; 60. Angle valve; 61. Support ring; 62. Lifting plate; 63. Guide column; 70. Motor; 80. Cylinder. Detailed Implementation

[0044] In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the appendix. Figure 1 The orientations or positional relationships shown are merely for the purpose of simplifying the description of the present invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0045] To make the objectives and advantages of this invention clearer, the invention will be specifically described below with reference to embodiments. It should be understood that the following text is only used to describe one or more specific embodiments of the invention and does not strictly limit the scope of protection specifically claimed by the invention. As used herein, the terms up and down and left and right are not limited to their strict geometric definitions, but include tolerances for reasonable and inconsistent machining or human errors. The specific features of the test control system for a butterfly valve are described in detail below:

[0046] An embodiment of the present invention:

[0047] Reference Figures 1-6 This invention provides a test and control system for butterfly valves, the system comprising:

[0048] Frame 10 is an overall frame constructed using national standard 4040 aluminum profiles, providing an installation foundation for all components;

[0049] The opening calibration module includes a host computer 40, which is electrically connected to the MCU of the vacuum butterfly valve and is used to calibrate that the actual opening of the valve plate of the vacuum butterfly valve is consistent with the input target opening.

[0050] The pressure control test module is used to test the pressure control capability of the vacuum butterfly valve after the opening calibration is completed. The pressure control test module specifically includes a test furnace 20, a vacuum pump 50 and interface components, and shares the host computer (4) with the opening calibration module.

[0051] The test furnace 20 is fixed on the frame 10. The test furnace 20 is a sealed cavity made of 304 stainless steel, consisting of a furnace body and a furnace cover connected by bolts. Its volume is approximately 50 liters. A vacuum sensor 21 is installed on the test furnace 20. In this embodiment, the vacuum sensor 21 is an INFICON PCG550 piezoelectric vacuum gauge with a measurement range of 1×10⁻⁶. -1 Pa to 1×10 5 Pa, the sensor is directly installed on the reserved interface on the furnace cover of the test furnace 20 through its own KF40 flange, and the inlet pipe 22 and outlet pipe 23 of the standard KF40 flange interface are welded on its peripheral wall. The vacuum sensor 21 is used to detect the vacuum degree inside the test furnace 20.

[0052] Vacuum pump 50 is connected to test furnace 20 and is used to evacuate test furnace 20 to a vacuum. In this embodiment, vacuum pump 50 is selected from the nXDS series rotary vane vacuum pump manufactured by Edwards Corporation.

[0053] The interface components include a main pipe 33, an angle valve 60, a first connecting pipe 34, and a diversion connecting pipe 32. The main pipe 33 is connected to the test furnace 20. The on / off state between the main pipe 33 and the first connecting pipe 34 is controlled by the angle valve 60. The flange of the vacuum butterfly valve is fixed between the lower end of the diversion connecting pipe 32 and the upper end of the first connecting pipe 34. The upper end of the diversion connecting pipe 32 is connected to the external environment.

[0054] In this embodiment, the angle valve 60 is a VX series vacuum angle valve manufactured by SMC Corporation of Japan. Its inlet and outlet are KF25 flanges. The outlet of each angle valve is connected to a branch pipe. The first connecting pipe 34 is a DN25 stainless steel pipe. Its upper end is connected to the flange of the vacuum butterfly valve to be tested through a flange, and its lower end is connected to the inlet of the angle valve.

[0055] The host computer 40 is electrically connected to the MCU, vacuum sensor 21, and vacuum pump 50. It inputs the target vacuum degree to the MCU, and the vacuum pump 50 evacuates the test furnace 20 to a vacuum. The vacuum sensor 21 acquires the actual vacuum degree and sends an analog signal to the host computer 40. The host computer 40 drives the MCU to control the valve plate to change its opening degree and records the single response time of the vacuum butterfly valve during the adjustment process. Through closed-loop control, the actual vacuum degree is adjusted to be close to the target vacuum degree. The host computer 40 evaluates the pressure control capability of the vacuum butterfly valve based on the cumulative response time.

[0056] In this embodiment, the host computer 40 is an industrial control computer (IPC). A set of vacuum butterfly valve test control program runs in the host computer 40. The program integrates user interaction, process control, data communication and data analysis functional modules to automatically execute the opening calibration and pressure control test process.

[0057] Specifically, in the opening calibration mode, the calibration sequence generation module built into the control program is used to automatically generate a series of target opening values ​​according to preset rules (e.g., from 0° to 90°, in 10° increments).

[0058] In this embodiment, the vacuum butterfly valve under test is the intelligent vacuum butterfly valve disclosed in patent number CN119244755B, which includes an STMicroelectronics STM32F103 series MCU with a built-in 12-bit ADC (analog-to-digital converter). The valve body integrates a stepper motor (model: 17HS4401) for driving the valve plate, and an absolute encoder (using AS5600 magnetic encoder chip) for detecting the actual rotation angle (opening degree) of the valve plate.

[0059] Specifically, the calibration process of the aperture calibration module includes the following steps:

[0060] S1. The host computer 40 sends a series of preset target opening value signals to the MCU of the vacuum butterfly valve;

[0061] S2. For each target opening value signal, the valve plate of the vacuum butterfly valve rotates by the corresponding angle, and the encoder inside the vacuum butterfly valve collects the actual opening value of the valve plate and feeds it back to the host computer via the MCU.

[0062] S3. The host computer 40 calculates the opening difference between the actual opening value and the input target opening value. Based on the opening difference, it generates and sends a control signal to the MCU of the vacuum butterfly valve to drive the valve plate to rotate, thereby reducing the opening difference.

[0063] S4. Iterate through S2-S3 until the opening difference is less than or equal to a preset tolerance threshold.

[0064] Specifically, the host computer 40 generates a control signal based on the opening difference value in step S3 using an incremental PID control algorithm.

[0065] Specifically, the inlet pipe 22 is connected to the main pipe 33 via the second connecting pipe 30, and the outlet pipe 23 is connected to the inlet of the vacuum pump 50 via the third connecting pipe 31. The inlet of the vacuum pump 50 and the mating end of the third connecting pipe 31 are both equipped with DN40 ISO-KF standard vacuum flanges. The two are connected and sealed by matching center rings and claw clamps to ensure the integrity and sealing of the vacuum system. A motor 70 (preferred model of motor 70 is YE2-100L-4, rated power 3kW) is set on one side of the vacuum pump 50. The two are directly connected to the host computer 40 via a coupling. The motor 70 is used to drive the vacuum pump 50 to perform vacuuming.

[0066] Specifically, the main pipe 33 is a pipe that is closed at one end and open at the other end. The second connecting pipe 30 is connected to the open end of the main pipe 33. Multiple branch pipes are fixed on the periphery of the main pipe 33. Multiple angle valves 60 are provided and correspond one-to-one with the multiple branch pipes. The air outlet of the angle valve 60 is connected to the branch pipe. Multiple first connecting pipes 34 are provided and correspond one-to-one with the multiple angle valves 60. The first connecting pipe 34 is connected to the air inlet of the angle valve 60. A fixed platform 11 is fixed on 10. The first connecting pipe 34 passes through the fixed platform 11 and is fixedly connected to it.

[0067] Specifically, multiple support rings 61 are fixed on the fixed platform 11. The support rings 61 are sleeved on the outer periphery of the first connecting pipe 34. Multiple circumferentially evenly distributed guide posts 63 are fixed on the support rings 61. The guide posts 63 pass through the through holes of the upper flange of the first connecting pipe 34. The through holes on the flange of the vacuum butterfly valve correspond one-to-one with the guide posts 63. When the flange of the vacuum butterfly valve abuts against the first connecting pipe 34, the guide posts 63 pass through the through holes of the upper flange.

[0068] Specifically, the lower end of the diversion connecting pipe 32 is divided into multiple diversion ends 322, and the diversion ends 322 are correspondingly set with the first connecting pipe 34. When the flange on the diversion end 322 abuts against the flange of the vacuum butterfly valve, the guide column 63 passes through the through hole of the flange on the diversion end 322. The upper end of the diversion connecting pipe 32 is set as the air inlet end 321 and is connected to the external environment. A lifting plate 62 is fixed between adjacent diversion ends 322. Multiple cylinders 80 corresponding to the lifting plate 62 are fixed on the lower end face of the fixed platform 11. The piston rod of the cylinder 80 passes through the fixed platform 11 upward and is fixedly connected to the lower end face of the lifting plate 62. The cylinder 80 is electrically connected to the host computer 40.

[0069] In this embodiment, cylinder 80 adopts the CDQ2B series thin cylinder from SMC. Cylinder 80 is connected to the control circuit through a solenoid valve (SMCSY series), and its lifting is ultimately controlled by the digital output card of the host computer 40.

[0070] Specifically, the closed-loop control process of the pressure control test module includes:

[0071] SS1. Input the target vacuum level into the MCU via the host computer 40;

[0072] SS2, the host computer 40 controls the vacuum pump to evacuate the test furnace 20 to a vacuum, and the vacuum sensor 21 continuously detects the actual vacuum level in the test furnace and sends an analog signal to the host computer 40 at a frequency of 10Hz.

[0073] SS3, the host computer 40 calculates the vacuum difference between the actual vacuum level and the target vacuum level, and sends it to the MCU;

[0074] SS4 and MCU generate control signals based on the vacuum difference through incremental PID control algorithm to drive the valve plate to rotate, thereby changing the opening of the vacuum butterfly valve. The encoder in the vacuum valve detects the change in valve plate angle and sends the analog signal to the host computer 40 via the MCU. The host computer 40 then records the single response time of the vacuum butterfly valve.

[0075] If the change in the opening degree of the vacuum butterfly valve causes a change in the vacuum degree inside the test furnace 20, then repeat SS2-SS4 until the actual vacuum degree approaches the target vacuum degree. The host computer 40 evaluates the pressure control capability of the vacuum butterfly valve based on the cumulative response time.

[0076] Specifically, the single response time of the vacuum butterfly valve recorded by the host computer 40 refers to the time elapsed from when the host computer 40 sends a control signal to when it receives the valve plate rotation analog signal fed back by the MCU.

[0077] The sum of the single response times is the total adjustment time for the actual vacuum level to reach and stabilize within the target vacuum level tolerance range from the initial value. The total adjustment time is used to quantitatively evaluate the pressure control capability and dynamic performance of the vacuum butterfly valve.

[0078] In practical use, this invention:

[0079] Connection between host computer 40 and the MCU of the vacuum butterfly valve under test: Host computer 40 provides multiple RS-485 communication ports through a MOXA UPort 1450 series multi-serial port card. The communication with each butterfly valve MCU under test adopts the Modbus RTU protocol. The specific wiring is as follows: the A / B data lines of RS-485 are connected to the corresponding terminals of the butterfly valve MCU communication interface, and share the DC 24V power ground provided by the host computer as the signal ground.

[0080] Connection between host computer 40 and vacuum sensor 21: The PCG550 vacuum sensor has a built-in RS-232 communication interface. The host computer 40 is connected to it through an RS-232 to USB adapter and reads the current vacuum level value by sending a specific command string.

[0081] Connection between host computer 40 and motor 70: The drive motor 70 of the vacuum pump is controlled by a three-phase AC contactor. The coil of the contactor is driven by a channel of the digital output card of the host computer 40, thereby realizing the start and stop control of the vacuum pump.

[0082] Connection between host computer 40 and cylinder 80: The solenoid valve coil controlling cylinder 80 is also connected to different channels of the digital output card of host computer 40, and the lifting / lowering action of cylinder is controlled by outputting high / low level.

[0083] When testing the vacuum butterfly valve under test, this invention:

[0084] The vacuum butterfly valve to be tested is placed on the fixed platform 11. The through hole on the flange of the vacuum butterfly valve is aligned with the guide post 63, and its flange is abutted against the upper flange of the first connecting pipe 34. The guide post 63 passes through the through hole on the flange of the vacuum butterfly valve. The host computer 40 controls the cylinder 80 to extend, thereby causing the lifting plate 62 to move downward, thereby driving the connecting pipe 32 to move downward until the diversion end 322 on it abuts against the flange of the vacuum butterfly valve. In a preferred embodiment, the upper end face of the first connecting pipe 34 and the lower end face of the diversion end 322 are both fixed with sealing rings to increase the sealing between the two and the vacuum butterfly valve.

[0085] By moving the diverter end 322 up and down, the disassembly and assembly of the vacuum butterfly valve under test can be accelerated, thereby improving the testing efficiency.

[0086] The specific process for calibrating the opening degree of the vacuum butterfly valve under test provided by this invention includes:

[0087] Step 1: The host computer 40 controls the first angle valve 60 to open, while closing the other angle valves 60. Then the vacuum butterfly valve connected to the first angle valve 60 enters the test preparation stage.

[0088] Step 2: The operator selects the "Opening Calibration" mode in the host computer software and enters the ID of the butterfly valve to be tested. The host computer sends a handshake command to the MCU of the butterfly valve through the RS-485 bus to establish communication.

[0089] Step 3: The control program in the host computer 40 generates the target opening value according to a preset sequence and drives the butterfly valve MCU to operate via the Modbus communication protocol. The specific process includes:

[0090] The calibration sequence generation module of the S3.1 control program automatically generates a preset target opening value sequence (e.g., 0°, 10°, 20°, ... 90°). For each target opening value in the sequence, the program's communication protocol stack will encapsulate it into a "write holding register" request frame conforming to the Modbus RTU protocol. This request frame specifies the device address of the target butterfly valve, the starting address of the register to be written (e.g., 0x0001, representing a specific register used to receive the target opening value), and the binary data after converting the target opening value (e.g., 20°).

[0091] S3.2 The packaged Modbus command is sent to the MCU of the target vacuum butterfly valve through the RS-485 communication interface of the host computer 40. The Modbus slave program embedded in the butterfly valve MCU parses the command, identifies it as a "write holding register" command, and then stores the received target opening value into its internal specified holding register.

[0092] S3.3 Once the target opening value is successfully written to the register, the main control loop of the butterfly valve MCU will immediately detect the change in the register value and then trigger its internal position closed-loop control program to prepare to drive the valve plate to rotate towards the target angle.

[0093] Step 4: Valve Plate Action and Feedback

[0094] a) After receiving the target opening value, the butterfly valve MCU starts its internal position closed-loop control program;

[0095] b) The position closed-loop control program first passes through I 2 The MCU reads bus data from the integrated magnetic encoder (AS5600), initiates a read operation on a specific register of the AS5600 to obtain a 12-bit raw angle value, and converts it into the current actual opening value of the valve plate using the formula: Actual opening value = (Raw angle value / 4095) * 90°. ;

[0096] c) The program enters a high-speed control loop, within which the following steps are executed sequentially:

[0097] Deviation calculation: Calculate the target opening degree Compared with the actual opening value The deviation e;

[0098] PID calculation: Input the deviation e into the incremental PID control algorithm to calculate the number and direction of pulses required to drive the stepper motor;

[0099] Signal output: Outputs pulse (PUL) and direction (DIR) signals to the stepper motor driver;

[0100] Status update: The motor drives the valve plate to rotate, and the encoder continuously feeds back new information. ;

[0101] d) Loop Termination: The above control loop is executed iteratively until the absolute value of the opening deviation e is less than or equal to the preset tolerance threshold (0.5° in this embodiment). At this time, the valve plate is considered to have accurately reached the target position, the MCU stops sending pulses, and the control loop is paused.

[0102] Step 5: Data Recording and Calibration

[0103] a) After positioning is completed, the butterfly valve MCU will feed back the final actual opening value to the host computer 40 via the Modbus protocol and write it into the input register requested by the host computer 40;

[0104] b) The host computer records this set of data (target opening command, actual opening feedback);

[0105] Step Six: Iteration and Mapping Table Generation:

[0106] Repeat steps three through five until all preset calibration points (e.g., 0°, 10°, ..., 90°) have been traversed. At this point, the control program of the host computer 40 has collected a complete calibration dataset for the currently tested butterfly valve. This dataset contains a series of paired ( , );

[0107] Subsequently, the program activates the calibration algorithm module and generates a unique opening calibration mapping table for this butterfly valve according to the following process:

[0108] S6.1 The program will collect the target opening value Defined as independent variable X, the corresponding actual opening value Defined as the dependent variable Y, thus forming a set of discrete two-dimensional data points (X). i Y i );

[0109] S6.2 The program uses the least squares polynomial fitting algorithm to find an nth-order polynomial function Y=f(X) such that the curve of the function is closest to all these data points as a whole, that is, to minimize the sum of squared fitting residuals of all data points.

[0110] S6.3 Based on the fitted calibration function Y=f(X), the program performs discretization calculations at a fixed resolution (e.g., one point per 1°) over the entire operating range of the butterfly valve (0° to 90°). For each possible input target opening command value X', it calculates the corresponding calibrated and compensated command output value X. compensated The calculation relationship is: X compensated =f (-1) (Y desired ), where Y desired It is the expected actual opening degree;

[0111] Ultimately, all ( X compensated The correspondence between the two valves is constructed into a one-dimensional lookup table, which is the unique opening calibration mapping table generated by the butterfly valve.

[0112] S6.4 In subsequent pressure control tests or practical applications of this butterfly valve, when it is necessary for the butterfly valve to rotate to a certain target opening degree Y... desired At this time, the control program of the host computer 40 will first search in the corresponding calibration mapping table or perform real-time calculation to obtain the calibration instruction value X that should be sent to the butterfly valve MCU. compensatedThis value is then written to the butterfly valve MCU via the Modbus protocol. In this way, the system achieves real-time software compensation for the nonlinear error and system error of the butterfly valve, ensuring that the final actual opening degree of the valve plate is always consistent with the target opening degree expected by the system.

[0113] Step 7: After the opening degree of the first vacuum butterfly valve is calibrated, the host computer 40 closes the angle valve 60 connected to it and opens the second angle valve 60, repeating steps 2 to 6.

[0114] The specific process for pressure control testing of the vacuum butterfly valve under test provided by this invention includes:

[0115] Step 1: The host computer 40 controls the first angle valve 60 to open, while closing the other angle valves 60. Then the vacuum butterfly valve connected to the first angle valve 60 enters the test preparation stage.

[0116] Step 2: Set the target vacuum level and PID control parameters in the host computer software 40. After clicking start, the host computer 40 starts the vacuum pump through the digital output card.

[0117] Step 3: Closed-loop control cycle:

[0118] a) The control program within the host computer 40 cyclically sends query commands (e.g., ASCII command strings in a specific format) to the vacuum sensor 21 via an RS-232 serial bus at a frequency of 10Hz. Upon receiving the command, the vacuum sensor 21 encapsulates its measured actual vacuum value in a data frame and returns it to the host computer. The host computer parses the data frame to obtain the actual vacuum value P within the current test furnace 20. actual ;

[0119] b) The control program of the host computer 40 calculates the actual vacuum degree P. actual With respect to the preset target vacuum level P target The difference between them, i.e., the vacuum error e(k) = P actual -P target ;

[0120] Subsequently, the host computer 40 generates a target opening instruction based on the error e(k) and the preset control logic. This instruction represents the opening that the butterfly valve theoretically needs to achieve in order to realize the target vacuum. It should be noted that in this step, the host computer 40 does not execute the specific PID algorithm, but performs high-level decision-making and instruction mapping.

[0121] c) The calculated target opening command is first compensated in real time by a unique opening calibration mapping table generated for the butterfly valve during the opening calibration stage to eliminate the mechanical and electrical errors of the butterfly valve itself. The compensated accurate command is written to the designated register of the butterfly valve MCU via RS-485 bus according to the Modbus RTU protocol.

[0122] d) Upon receiving the compensated target opening command, the butterfly valve MCU immediately activates its internally embedded intelligent control program, as disclosed in patent CN119244755B. The core flow of this program is as follows:

[0123] SS1. Read the data from the magnetic encoder (AS5600) via the I²C bus to obtain the current actual opening degree of the valve plate;

[0124] SS2. Compare the received target opening with the actual opening to obtain the opening deviation;

[0125] The SS3 and MCU automatically determine and call the corresponding incremental PID algorithm (first, third or fourth incremental PID algorithm) based on their internal logic (e.g., based on vacuum ratio, etc.) to calculate the precise stepper motor drive quantity.

[0126] SS4 and MCU convert the driving quantity into a pulse signal, which drives the stepper motor and rotates the valve plate to the target position.

[0127] e) When the valve plate rotation is completed, the butterfly valve MCU will send a "action completed" signal to the host computer 40. The host computer 40 starts a high-precision timer at the same time as issuing the control command, and stops when it receives this feedback signal, thereby recording the single response time of this control.

[0128] The triggering process of the high-precision timer is as follows:

[0129] At the moment when the host computer 40 sends the last byte of the control command to the butterfly valve MCU via the RS-485 bus, its control program synchronously calls the high-precision timer API to record the current high-precision timestamp T1. This operation can be regarded as starting the timer.

[0130] Subsequently, the host computer 40 continuously monitors the RS-485 bus, waiting for the "action completed" feedback signal returned by the butterfly valve MCU. The moment the host computer fully receives and parses the feedback signal, the program calls the high-precision timer API again to record a new timestamp T2. This operation can be regarded as stopping the timer.

[0131] The single response time ΔT of this control was calculated as follows: ΔT = T2 - T1.

[0132] This time ΔT precisely represents the total time elapsed from the issuance of the control command to the butterfly valve MCU receiving, processing, and driving the valve plate to the specified position, and finally reporting to the host computer. The host computer 40 stores this response time ΔT in the cumulative array in memory for subsequent performance evaluation.

[0133] Step 4: Changes in the valve plate opening will cause changes in the vacuum level inside the test furnace 20. The vacuum sensor 21 will detect this change and feed it back to the host computer 40, starting the next control cycle. This process repeats continuously.

[0134] Step 5: Test Termination and Evaluation

[0135] When the actual vacuum level enters the tolerance range of ±2% of the target vacuum level and remains stable for more than 3 seconds, the host computer 40 determines that the system has reached stability and the control cycle ends.

[0136] The software automatically accumulates all single response times ΔT during the entire adjustment process to obtain the total adjustment time.

[0137] Performance evaluation: The host computer outputs the total adjustment time and outputs whether the pressure control capability of the vacuum butterfly valve is qualified according to the preset level standard.

[0138] Those skilled in the art will appreciate that various modifications to the above embodiments can be made without departing from the overall spirit and concept of the present invention. All such modifications fall within the protection scope of the present invention. The protection scheme of the present invention is defined by the appended claims.

Claims

1. A test control system for a butterfly valve, characterized by, The system comprises: a rack (10); an opening degree calibration module, which comprises an upper computer (40) electrically connected with the MCU of the vacuum butterfly valve, and is used for calibrating the actual opening degree of the valve plate of the vacuum butterfly valve to be consistent with the input target opening degree; a pressure control test module, which is used for testing the pressure control capability of the vacuum butterfly valve after the opening degree calibration is completed, and specifically comprises a test furnace (20), a vacuum pump (50) and an interface assembly, and shares the upper computer (40) with the opening degree calibration module; wherein the test furnace (20) is fixed on the rack (10), a vacuum sensor (21) is installed on the test furnace (20), and the vacuum sensor (21) is used for detecting the vacuum degree inside the test furnace (20); the vacuum pump (50) is connected with the test furnace (20) and is used for pumping the test furnace (20) to vacuum; the interface assembly comprises a main pipeline (33), an angle valve (60), a first connecting pipe (34) and a shunt communication pipe (32), the main pipeline (33) is connected with the test furnace (20), the on-off state between the main pipeline (33) and the first connecting pipe (34) is controlled by the angle valve (60), the flange of the vacuum butterfly valve is fixed between the lower end of the shunt communication pipe (32) and the upper end of the first connecting pipe (34), and the upper end of the shunt communication pipe (32) is in communication with the external environment; the upper computer (40) is electrically connected with the MCU, the vacuum sensor (21) and the vacuum pump (50), inputs the target vacuum degree to the MCU, the vacuum pump (50) pumps the test furnace (20) to vacuum, the vacuum sensor (21) acquires the actual vacuum degree and sends an analog signal to the upper computer (40), the upper computer (40) drives the MCU to control the valve plate to change its opening degree, records the single response time of the vacuum butterfly valve in the adjustment process, realizes the adjustment of the actual vacuum degree to approach the target vacuum degree through closed-loop control, and evaluates the pressure control capability of the vacuum butterfly valve based on the accumulated response time.

2. The test control system of claim 1, wherein, The calibration process of the opening degree calibration module comprises the following steps: S1, the upper computer (40) sends a series of preset target opening degree value signals to the MCU of the vacuum butterfly valve; S2, for each target opening degree value signal, the valve plate of the vacuum butterfly valve rotates by a corresponding angle, the actual opening degree value of the valve plate is collected by the encoder in the vacuum butterfly valve and is fed back to the upper computer (40) via the MCU; S3, the upper computer (40) calculates the opening degree difference value between the actual opening degree value and the input target opening degree value, generates and sends a control signal to the MCU of the vacuum butterfly valve based on the opening degree difference value, so as to drive the valve plate to rotate and reduce the opening degree difference value; S4, iteratively execute S2-S3 until the opening degree difference value is less than or equal to a preset tolerance threshold.

3. A test control system for a butterfly valve according to claim 2, wherein, The upper computer (40) generates the control signal through the incremental PID control algorithm based on the opening degree difference value of step S3.

4. The test control system for a butterfly valve according to claim 1, wherein The test furnace (20) is provided with an air inlet pipe (22) and an air outlet pipe (23) on the peripheral wall, the air inlet pipe (22) is connected with the main pipeline (33) through the second connecting pipe (30), the air outlet pipe (23) is connected with the air inlet of the vacuum pump (50) through the third connecting pipe (31), one side of the vacuum pump (50) is provided with a motor (70), the motor (70) is electrically connected with the upper computer (40), and the motor (70) is used for driving the vacuum pump (50) to perform the vacuumizing action.

5. A test control system for a butterfly valve according to claim 4, wherein, The main pipeline (33) is a pipeline with one end closed and the other end open, the second connecting pipe (30) is connected with the open end of the main pipeline (33), a plurality of branch pipes are fixedly arranged on the peripheral wall of the main pipeline (33), a plurality of angle valves (60) are arranged and correspond to the plurality of branch pipes one by one, the air outlets of the angle valves (60) are connected with the branch pipes, a plurality of first connecting pipes (34) are arranged and correspond to the plurality of angle valves (60) one by one, the first connecting pipes (34) are connected with the air inlets of the angle valves (60), and the first connecting pipes (34) penetrate through the fixed table (11) and are fixedly connected with the fixed table (11).

6. A test control system for a butterfly valve according to claim 5, wherein, A plurality of supporting rings (61) are fixedly arranged on the fixed table (11), the supporting rings (61) are arranged on the outer periphery of the first connecting pipe (34), a plurality of guide columns (63) are fixedly arranged on the supporting rings (61) and are uniformly distributed in the circumferential direction, the guide columns (63) penetrate through the through holes of the flanges on the upper ends of the first connecting pipes (34), the through holes of the flanges of the vacuum butterfly valves correspond to the guide columns (63) one by one, and when the flanges of the vacuum butterfly valves abut against the first connecting pipes (34), the guide columns (63) penetrate through the through holes of the flanges.

7. A test control system for a butterfly valve according to claim 6, wherein, The lower end of the shunt communication pipe (32) is divided into a plurality of shunt ends (322), the shunt ends (322) are correspondingly arranged with the first connecting pipes (34), when the flanges on the shunt ends (322) abut against the flanges of the vacuum butterfly valves, the guide columns (63) penetrate through the through holes of the flanges on the shunt ends (322), the upper end of the shunt communication pipe (32) is arranged as an air inlet end (321) and communicates with the external environment, the adjacent shunt ends (322) are fixedly provided with lifting plates (62), a plurality of air cylinders (80) corresponding to the lifting plates (62) are fixedly arranged on the lower end surface of the fixed table (11), the piston rods of the air cylinders (80) penetrate through the fixed table (11) in the upward direction and are fixedly connected with the lower end surfaces of the lifting plates (62), and the air cylinders (80) are electrically connected with the upper computer (40).

8. The test control system of claim 1, wherein, The closed-loop control process of the pressure control test module specifically includes: SS1, inputting a target vacuum degree into the MCU through the upper computer (40); SS2, the upper computer (40) controls the vacuum pump to vacuumize the test furnace (20), the vacuum sensor (21) continuously detects the actual vacuum degree in the test furnace and sends an analog signal to the upper computer (40) at a frequency of 10 Hz; SS3, the upper computer (40) calculates the vacuum degree difference between the actual vacuum degree and the target vacuum degree and sends the vacuum degree difference to the MCU; SS4, MCU generates control signals based on vacuum difference through incremental PID control algorithm to drive valve plate to rotate, thereby changing the opening degree of vacuum butterfly valve. The encoder in vacuum valve detects the change in valve plate angle and sends the analog signal to the host computer (40) via MCU. Then the host computer (40) records the single response time of vacuum butterfly valve. SS5. Changes in the opening degree of the vacuum butterfly valve cause changes in the vacuum degree inside the test furnace (20). Then repeat SS2-SS4 until the actual vacuum degree approaches the target vacuum degree. The host computer (40) evaluates the pressure control capability of the vacuum butterfly valve based on the cumulative response time.

9. A test control system for a butterfly valve according to claim 8, wherein, The single response time of the vacuum butterfly valve recorded by the host computer (40) refers to the time elapsed from when the host computer (40) sends out a control signal to when it receives the valve plate rotation simulation signal fed back by the MCU. The sum of the single response times is the total adjustment time for the actual vacuum level to reach and stabilize within the target vacuum level tolerance range from its initial value. This total adjustment time is used to quantitatively evaluate the pressure control capability and dynamic performance of the vacuum butterfly valve.

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