A pneumatic proportional valve control method, system and storage medium thereof

Abstract

The present application relates to the field of pneumatic proportional valves, and in particular to a pneumatic proportional valve control method, system and storage medium thereof, which includes obtaining a dead zone friction value; determining a breakthrough signal through the dead zone friction value and a preset breakthrough time value; obtaining a valve input value; determining an output signal through the breakthrough signal and the valve input value, and outputting the output signal to control the valve core. The present application has the effect of reducing the influence of dead zone friction on precise control.

Description

Technical Field

[0001] The present application relates to the field of pneumatic proportional valves, and in particular to a pneumatic proportional valve control method, system and storage medium thereof. Background Art

[0002] A pneumatic proportional valve is a valve that uses compressed air as a power source and controls the gas flow by adjusting the valve opening. The compressed air pushes the valve core to move. With the long-term use of the pneumatic proportional valve, the internal resistance may increase, resulting in a smaller valve core movement distance when the same current and voltage are input, or even falling into the dead zone, and the valve core movement cannot be controlled; the static friction that needs to be overcome by the diaphragm or valve core movement may also increase, resulting in the valve core being unable to move when the same current and voltage are input. This is unavoidable for analog signal control of pneumatic proportional valves, so it is urgent to develop a pneumatic proportional valve that can be precisely controlled by digital signals. Summary of the invention

[0003] In order to improve the problem of interference caused by dead zone on the control of pneumatic proportional valve, the present application provides a pneumatic proportional valve control method, system and storage medium thereof.

[0004] The present application provides a pneumatic proportional valve control method, which adopts the following technical solution:

[0005] A pneumatic proportional valve control method, comprising:

[0006] Get the dead zone friction value;

[0007] Determine a breakthrough signal by using the dead zone friction value and a preset breakthrough time value;

[0008] Get valve input value;

[0009] An output signal is determined by the breakthrough signal and the valve input value, and is output to control the valve core.

[0010] By adopting the above technical solution, the error caused by the force used to overcome the dead zone friction, that is, the calculation of the dead zone friction value, is calculated in advance, and then the difference is calculated in combination with the valve input value, so that the valve core only needs to move the difference distance to reach the target position after starting, thereby reducing the influence of the dead zone friction on the moving valve core.

[0011] Optionally, obtaining the dead zone friction value includes:

[0012] Get the initial friction value, get the valve core displacement value, and get the usage time value;

[0013] Determine the dead zone predicted friction value by using the initial friction value, the usage time value, and a preset aging threshold value;

[0014] Determine a test signal by using the dead zone predicted friction value and a preset test work time value;

[0015] Determine test data by using the valve core displacement value and the test signal;

[0016] The new dead zone predicted friction value is re-determined by using the test data and a preset adjustment threshold, and the new dead zone predicted friction value is used as the dead zone friction value.

[0017] By adopting the above technical solution, the dead zone friction value is calculated and estimated through the aging threshold, and then the estimated dead zone friction value is corrected through testing and calculation, so that the dead zone friction value remains accurate during the extended use time, thereby improving stability and accuracy.

[0018] Optional, including:

[0019] Determine the minimum displacement value by using the dead zone friction value and a preset maximum deceleration threshold;

[0020] If the minimum displacement value is smaller than the valve input value, a valve core deceleration value is determined by the dead zone friction value and the valve input value, and the output signal is determined by the valve core deceleration value.

[0021] By adopting the above technical solution, when the minimum displacement value is less than the valve input value, the valve core deceleration value is obtained by calculation, so that the valve core can be evenly decelerated after breaking through the static friction of the dead zone friction, thereby reducing the damage to the valve core caused by deceleration, reducing the reaction force caused by deceleration to a minimum, and protecting the valve core.

[0022] Optionally, if the minimum displacement value is greater than the valve input value, comprising:

[0023] Determine a displacement adjustment value by using the minimum displacement value and the valve input value;

[0024] Determine the valve core deceleration value by using the displacement adjustment value and the dead zone friction value;

[0025] Determine the valve core pull-back value by using the displacement adjustment value, the minimum displacement value, and the dead zone friction value;

[0026] The output signal is determined by the valve core deceleration value and the valve core pull-back value.

[0027] By adopting the above technical solution, when the minimum displacement value is greater than the valve input value, by first moving a greater distance and then pulling back to the specified position of the valve input value, the explosive speed generated by the valve core breaking through the dead zone friction is reduced, and the probability of exceeding the specified position required by the valve input value even if it is decelerated at the fastest speed, thereby greatly improving the control accuracy and reducing the influence of the dead zone friction on the valve core control.

[0028] Optionally, if the minimum displacement value is greater than the valve input value, comprising:

[0029] Determine the shortest working time value by using the displacement adjustment value and the maximum deceleration threshold;

[0030] Determine a maximum initial speed value by using the shortest working time value and the maximum deceleration threshold;

[0031] The output signal is determined by the maximum initial speed value and the valve core pull-back value.

[0032] By adopting the above technical solution, the shortest working time and the fastest response speed can be achieved, and it can be applied to more urgent working conditions, such as emergency shutdown in the chemical industry.

[0033] Optional, including:

[0034] Determining the dead zone friction test signal by a preset initial position value, a preset maximum displacement value of the valve core, a preset force adjustment value, and the maximum deceleration threshold;

[0035] Obtaining a dead zone friction test value through the dead zone friction test signal and recording it;

[0036] The dead zone friction test signal is adjusted by the initial position value and the preset misalignment test value, thereby determining a new dead zone friction test signal;

[0037] If the subsequent dead zone friction test value is the same as the previous dead zone friction test value, the dead zone friction test signal is adjusted by a preset offset adjustment value to determine a new dead zone friction test signal.

[0038] By adopting the above technical solution, the dead zone friction value of the inner wall of the pneumatic proportional valve displaced by the entire valve core is tested, so that the dead zone friction value can be corrected and unified, reducing the probability of large deviations due to the accumulation of small errors caused by redundancy and calculation during long-term use, thereby improving accuracy.

[0039] The present application provides a pneumatic proportional valve system, which adopts the following technical solution:

[0040] A pneumatic proportional valve system, comprising:

[0041] Inlet and outlet ports, used for air intake and exhaust to control the pressure on the valve core;

[0042] A detection module, used to detect the position of the valve core and obtain the displacement value of the valve core;

[0043] The processing module is used to calculate and process the data to obtain the signal for controlling the valve core and output it, and store the data for future use.

[0044] By adopting the above technical solution, the valve core state is detected by the detection module, and the air inlet and outlet at the air inlet and outlet ends are calculated and controlled by the processing module, thereby realizing the control of the valve core.

[0045] The present application provides a computer-readable storage medium, which adopts the following technical solution:

[0046] A computer-readable storage medium stores a computer program that can be loaded by a processor and executed by a pneumatic proportional valve control method.

[0047] By adopting the above technical solution, the computer program is stored in a computer-readable storage medium.

[0048] In summary, the present application includes at least one of the following beneficial technical effects:

[0049] 1. Reduce the influence of dead zone friction on the moving valve core.

[0050] 2. Estimate and correct the dead zone friction value to ensure that the dead zone friction value remains accurate during extended use, thereby improving stability and accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 It is a flow chart of a pneumatic proportional valve control method in an embodiment of the present application.

[0052] Figure 2 is a flow chart of step S2.

[0053] Figure 3 It is a flowchart of step S3.

[0054] Figure 4 It is a flowchart of step S6.

[0055] Figure 5 It is an overall schematic diagram of a pneumatic proportional valve system in an embodiment of the present application.

[0056] Figure 6 is along Figure 5 Schematic diagram of the cross section along line AA.

[0057] Figure 7It is a module schematic diagram of a pneumatic proportional valve system in an embodiment of the present application.

[0058] Explanation of the reference numerals: 1. air inlet and outlet; 2. detection module; 3. processing module; 31. processor; 32. database. DETAILED DESCRIPTION

[0059] The following is combined with Figure 1-7 This application is described in further detail.

[0060] The present application embodiment discloses a pneumatic proportional valve control method. Figure 1 , the pneumatic proportional valve control method includes the following steps:

[0061] S1, obtain the dead zone friction value and the valve input value;

[0062] S11, determining a breakthrough signal through the dead zone friction value and a preset breakthrough time value;

[0063] S12, determine the output signal through the breakthrough signal and the valve input value, and output it to control the valve core.

[0064] In detail: the dead zone friction value is the maximum static friction that needs to be overcome from static to dynamic. The valve input value is the data input by the user on how much the valve core needs to move to open the valve. The breakthrough time value is the time for doing work. If the dead zone friction value is 1000N and the breakthrough time value is 0.1s, it means that a force of 1000N needs to be applied to the diaphragm or valve core for 0.1s, and this data is converted into a breakthrough signal, and then combined with the valve input value, that is, how much distance the valve core needs to move after overcoming the dead zone friction to reach the specified required position. Suppose the valve input value is 1cm. If a force of 1000N lasts for 0.1, it will push the valve core to move 0.1cm, and then it is obtained that it still needs to move 0.9cm. The breakthrough signal and the data that still needs to move 0.9cm are converted into output signals and output to the air supply mechanism to apply pressure to control the valve core.

[0065] Reference Figure 2 , obtaining the dead zone friction value includes the following steps:

[0066] S2, obtaining an initial friction value, obtaining a valve core displacement value, and obtaining a usage time value;

[0067] S21, determining the dead zone estimated friction value according to the initial friction value, the usage time value, and the preset aging threshold;

[0068] S22, determining a test signal by using the dead zone estimated friction value and a preset test working time value;

[0069] S23, determining test data through the valve core displacement value and the test signal;

[0070] S24. Re-determine a new dead zone predicted friction value based on the test data and a preset adjustment threshold, and use the new dead zone predicted friction value as the dead zone friction value.

[0071] Details: The initial friction value is the initial static friction at the time of leaving the factory, which can generally be provided directly by the manufacturer or can also be obtained through testing. The use time value is the time from the start of the pneumatic proportional valve being put into use to the present. The valve core displacement value is the displacement data of the valve core obtained by real-time detection, or it can be the displacement distance of the diaphragm. The aging threshold is a relationship or table related to time. If the aging threshold is 0.1t, if the use time value is 90 days, the aging threshold can be calculated to be 0.1*90=9. If the initial friction value is 1000N, the dead zone estimated friction value can be 1000+9=1009N. If the test work time value is 0.05s, then the value obtained indicates that the applied A force of 1009N is applied to the valve core for 0.05s, and then a test signal of a reverse force of 1009N is applied for 0.05s, that is, the test signal includes two processes of pushing out and pulling back. If the valve core is pushed, the valve core is displaced, and the valve core displacement value is greater than 0. At this time, the corresponding test data can be obtained. At this time, the expected dead zone friction value is used as the dead zone friction value. If the valve core is not pushed, the valve core displacement value is 0. Assuming the adjustment threshold is 1N, the new expected dead zone friction value is determined again as 1009+1=1010N, and then the test signal is output again for testing until the valve core is pushed. The expected dead zone friction value of that time when the valve core is pushed is used as the dead zone friction value.

[0072] Reference Figure 3 , further comprising the following steps:

[0073] S3, determining the minimum displacement value through the dead zone friction value and the preset maximum deceleration threshold;

[0074] S31. If the minimum displacement value is less than the valve input value, the valve core deceleration value is determined by the dead zone friction value and the valve input value, and the output signal is determined by the valve core deceleration value.

[0075] Details: Due to the existence of the dead zone friction value, in order to make the valve core move, a larger force must be used to overcome the dead zone friction value. However, there will be a maximum deceleration acceleration when the valve core stops after moving. If the deceleration speed is greater than this acceleration, that is, it stops too quickly, it will cause damage to the valve core or other components. This maximum deceleration acceleration is the maximum deceleration threshold. The force required to overcome the dead zone friction, that is, the dead zone friction value and the maximum deceleration threshold, can be used to calculate the shortest displacement of the valve core when it stops immediately after moving without damaging the pneumatic proportional valve, that is, the minimum displacement value. Suppose the dead zone friction value is 1000N, and a speed of 10cm / s is generated directly after moving. Suppose the maximum deceleration threshold is 100cm / s 2, the time required for deceleration is 0.1s, and the minimum displacement value is (10+0) / 2*0.1=0.5cm. If the minimum displacement value is less than the valve input value, and the valve input value is 1cm, then it can be calculated that if the valve is decelerated uniformly before reaching the target position, the valve core deceleration value can be calculated to be At this time, the output signal representing this data is output to the air inlet and outlet equipment to achieve 1000N pushing the valve core at 50cm / s 2 The valve core can be stopped at the target position by decelerating the acceleration.

[0076] Reference Figure 3 , in the judgment of step S31, if the minimum displacement value is greater than the valve input value, the following steps are also included: S4, determining the displacement adjustment value by the minimum displacement value and the valve input value;

[0077] S41, determining the valve core deceleration value through the displacement adjustment value and the dead zone friction value;

[0078] S42, determining the valve core pull-back value according to the displacement adjustment value, the minimum displacement value, and the dead zone friction value;

[0079] S43, determining the output signal through the valve core deceleration value and the valve core pull-back value.

[0080] Details: When the minimum displacement value is greater than the valve input value, it means that even if the valve core stops moving at the fastest speed after starting, the displacement distance generated exceeds the required displacement distance, so it needs to be pulled back. If the minimum displacement value is 0.5cm and the valve input value is 0.3cm, the displacement adjustment value can be calculated to be 0.3+0.5=0.8cm, that is, after overcoming the dead zone friction movement, the valve core first moves a distance of 0.8cm, and then pulls back to the target position, and needs to move 0.8cm. If a speed of 10cm / s is directly generated under the thrust of the dead zone friction value, the valve core deceleration value can be calculated to be 10 2 / 2 / 0.8=62.5cm / s 2 At this time, the output signal contains a frequency of 62.5 cm / s 2 The target position is 0.3cm, that is, it can be pulled back from the position of 0.8cm to the position of 0.5cm, that is, it can be pulled back from the position corresponding to the displacement adjustment value to a position distance of the minimum displacement value. At this time, the valve core pull-back value is the pulling force corresponding to the dead zone friction value, and then decelerate at the maximum deceleration threshold to reach the position corresponding to the valve input value. At this time, the output signal includes the dead zone friction value after being pushed at 62.5cm / s 2 The acceleration is uniformly decelerated, and then pulled at the dead zone friction value and then at 100cm / s 2 The acceleration is uniformly decelerated.

[0081] Reference Figure 3 , in the judgment of step S31, if the minimum displacement value is greater than the valve input value, the following steps are also included: S5, determining the shortest working time value by the displacement adjustment value and the maximum deceleration threshold;

[0082] S51, determining a maximum initial speed value by using a minimum working time value and a maximum deceleration threshold;

[0083] S52, determining the output signal according to the maximum initial speed value and the valve core pull-back value.

[0084] Detailed: When the minimum displacement value is greater than the valve input value, it means that even if the valve core stops moving at the fastest speed after starting, the displacement distance generated exceeds the required displacement distance, so it needs to be pulled back. If the minimum displacement value is 0.5cm and the valve input value is 0.3cm, the displacement adjustment value can be calculated to be 0.3+0.5=0.8cm. The maximum acceleration acceleration and the maximum deceleration acceleration have the same force on the valve core and other pneumatic proportional valve components, so the maximum acceleration value is equal to the maximum deceleration threshold. When the valve core overcomes the dead zone friction to move, the initial speed is 10cm / s, and the maximum deceleration threshold is 100cm / s. 2 , the maximum acceleration value is also 100cm / s 2 , let the acceleration time be t1, let the deceleration time be t2, then the inequality is So we can calculate That is, first input the dead zone friction value to overcome the dead zone friction, then directly push with the maximum force, or directly provide the maximum force to directly break through the dead zone friction. However, since the initial speed is determined by static friction, the initial speed is still 10cm / s, so the initial speed of 10cm / s is increased by 100cm / s. 2 The acceleration is 0.014s, and then 100cm / s 2 The acceleration is decelerated by 0.114s to achieve the shortest working time. At this time, the shortest working time value is 0.014+0.114=0.128s, and then the valve core is pulled back with the thrust of the dead zone friction value that breaks through the dead zone friction. 2 The acceleration and deceleration can stop at the target position corresponding to the valve input value. At this time, the output signal includes pushing the valve core with maximum force for 0.014s, then decelerating with maximum force for 0.114s, then pulling the valve core back with the force of the dead zone friction value, and then decelerating with maximum force for 0.1s to reach the target position corresponding to the valve input value. The priority strategy of step S5 is different from that of step S4. If the fastest speed response is required and the shortest working time is the highest priority strategy, then the user can select step S5. If the service life is the highest priority strategy, use step S4.

[0085] Reference Figure 4 , further comprising the following steps:

[0086] S6, determining the dead zone friction test signal through a preset initial position value, a preset maximum displacement value of the valve core, a preset force adjustment value, and a maximum deceleration threshold;

[0087] S61, obtaining a dead zone friction test value through a dead zone friction test signal, and recording it;

[0088] S62, adjusting the dead zone friction test signal by using the initial position value and the preset misalignment test value, thereby determining a new dead zone friction test signal;

[0089] S63: If the subsequent dead zone friction test value is the same as the previous dead zone friction test value, the dead zone friction test signal is adjusted by a preset offset adjustment value to determine a new dead zone friction test signal.

[0090] Detailed: Set the initial position value to 0, the maximum displacement value of the valve core to 10, and the maximum deceleration threshold to 100 cm / s 2, and the starting speed of the valve core is related to the dead zone friction. If the dead zone friction value is 1000N and the initial speed is 10cm / s, it will decelerate at the maximum deceleration threshold immediately after being pushed, and the moving distance is 0.5cm. At this time, the dead zone friction value recorded as the dead zone friction value of 0 position is 1000N, and the position moves to 0.5cm. If the dead zone friction increases due to long-term use, or the inner wall is uneven, resulting in an increase in the dead zone friction force that needs to be overcome, then the dead zone friction value of 1000N cannot push the valve core to move. If the force adjustment value is 10N, the thrust is recalculated to make the dead zone friction value reach 1010N. If it still cannot be pushed, the force adjustment value is continuously increased until it is pushed. At this time, the dead zone friction value may reach 1200N. At this time, the initial speed may be 12cm / s, and the moving distance is 0.72cm. At this time, the dead zone friction test value is recorded as 1200N at the position of 0.5cm, and the position reaches 1.22cm. Then when the position reaches, for example, 9.6cm , and the distance between the maximum displacement value of the valve core 10cm and the minimum displacement distance 0.5cm is less than the minimum displacement distance 0.5cm, the valve core is pulled back, and the target position of the pullback is adjusted by the misalignment test value. If the misalignment test value is set to 0.1cm, the valve core is pulled back to the position of 0.1cm for testing again instead of the position of 0. At the same time, if in the test, the valve core is pushed to the same position as the previous test from 0 when the second test starts from 0.1cm, for example, the valve core is pushed from the 0.1cm position, and the dead zone friction value reaches 1050N before pushing, and the valve core is pushed a distance of 0.6cm. At this time, the valve core is at the position of 0.7cm, and when the valve core is pushed at the 0 position, the dead zone friction value of 1100N pushes it to the position of 0.7cm. At this time, the valve core stops at the same position for both tests, that is, at the position of 0.7cm. If the misalignment adjustment value is 50N, then in the second test, an additional force of 50N will be applied than the first time to prevent it from stopping at the same position later.

[0091] The present application embodiment discloses a pneumatic proportional valve system. Figure 5 and Figure 6 and Figure 7The pneumatic proportional valve system includes an air inlet and outlet 1, a detection module 2 and a processing module 3. The air inlet and outlet 1 is used to connect with an external air supply device to realize air inlet and outlet, adjust the air pressure on the diaphragm, and thus control the position of the valve core. The detection module 2 includes multiple sensors, such as an infrared sensor or a laser sensor for detecting distance, etc., which detects the position of the diaphragm or the valve core to obtain the valve core displacement value. The processing module 3 includes a processor 31 and a database 32. The processor 31 is used to receive data detected by sensors such as the valve core displacement value and the valve input value, as well as data input by the user, and obtains an output signal, a test signal, and a dead zone friction test signal after calculation to control the valve core. The database 32 is used to store data, such as various preset data, breakthrough time value, initial friction value, test work time value and other data, and is used for the processor 31 to call for calculation. At the same time, the database 32 can also store data combined with time to generate a work log.

[0092] The processor 31 may include a central processing unit such as a CPU or MPU or a host system built around a CPU or MPU, including hardware or software. After the meter has a processor 31, people can freely control the metering instrument by programming so that it can run according to people's wishes. The processor 31 can control local measurement transmission, remote measurement transmission, remote communication, etc. through internal protocols. Internal protocols generally refer to all protocols that achieve mutual communication or linking within the same metering instrument or the same system, including: human-computer interaction protocols, software / hardware (interface) protocols, chip bus (C-Bus) protocols, internal bus (I-Bus) protocols, etc., some or all of the protocols. With the development of integrated circuit technology, some of the protocols belonging to the external bus (E-Bus) protocol are also classified as internal protocols after the external bus (E-Bus) is integrated into the chip.

[0093] The present application embodiment discloses a computer-readable storage medium. Figure 1 The computer-readable storage medium includes a computer program that can be loaded and executed by the processor 31 to control the pneumatic proportional valve.

[0094] Computer-readable storage media include, for example, various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0095] 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 pneumatic proportional valve control method, characterized in that: include: Get the dead zone friction value; Determine a breakthrough signal by using the dead zone friction value and a preset breakthrough time value; Get valve input value; An output signal is determined by the breakthrough signal and the valve input value, and outputted to control the valve core; Get the initial friction value, get the valve core displacement value, and get the usage time value; Determine the dead zone predicted friction value by using the initial friction value, the usage time value, and a preset aging threshold value; Determine a test signal by using the dead zone predicted friction value and a preset test work time value; Determine test data by using the valve core displacement value and the test signal; The new dead zone predicted friction value is re-determined by using the test data and a preset adjustment threshold, and the new dead zone predicted friction value is used as the dead zone friction value.

2. A pneumatic proportional valve control method according to claim 1, characterized in that: include: Determine the minimum displacement value by using the dead zone friction value and a preset maximum deceleration threshold; If the minimum displacement value is smaller than the valve input value, a valve core deceleration value is determined by the dead zone friction value and the valve input value, and the output signal is determined by the valve core deceleration value.

3. A pneumatic proportional valve control method according to claim 2, characterized in that: If the minimum displacement value is greater than the valve input value, including: Determine a displacement adjustment value by using the minimum displacement value and the valve input value; Determine the valve core deceleration value by using the displacement adjustment value and the dead zone friction value; Determine the valve core pull-back value by using the displacement adjustment value, the minimum displacement value, and the dead zone friction value; The output signal is determined by the valve core deceleration value and the valve core pull-back value.

4. A pneumatic proportional valve control method according to claim 3, characterized in that: If the minimum displacement value is greater than the valve input value, including: Determine the shortest working time value by using the displacement adjustment value and the maximum deceleration threshold; Determine a maximum initial speed value by using the shortest working time value and the maximum deceleration threshold; The output signal is determined by the maximum initial speed value and the valve core pull-back value.

5. A pneumatic proportional valve control method according to claim 2, characterized in that: include: Determine the dead zone friction test signal by using a preset initial position value, a preset maximum displacement value of the valve core, a preset force adjustment value, and the maximum deceleration threshold; Obtaining a dead zone friction test value through the dead zone friction test signal and recording it; The dead zone friction test signal is adjusted by the initial position value and the preset misalignment test value, thereby determining a new dead zone friction test signal; If the subsequent dead zone friction test value is the same as the previous dead zone friction test value, the dead zone friction test signal is adjusted by a preset offset adjustment value to determine a new dead zone friction test signal.

6. A pneumatic proportional valve system, using the pneumatic proportional valve control method according to claim 1, characterized in that: include: An air inlet and outlet port (1) for air intake and air discharge to control the pressure on the valve core; A detection module (2) is used to detect the position of the valve core and obtain the displacement value of the valve core; The processing module (3) is used to calculate and process the data to obtain a signal for controlling the valve core and output it, and to store the data for later use.

7. A computer-readable storage medium, characterized in that: The device stores a computer program which can be loaded by a processor and executes a pneumatic proportional valve control method according to any one of claims 1 to 5.

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