A pilot valve control method and device based on data detection automatic pressure regulation

Abstract

The application discloses a pilot valve control method and device based on automatic pressure regulation of data detection, relates to the technical field of pilot valves, and comprises the following steps: acquiring the medium pressure of a piston containing cavity in real time through a pressure sensor, and acquiring the displacement of a piston shaft in real time through a displacement sensor; determining a target displacement based on the medium pressure and a pre-stored pressure-displacement correlation curve; generating an adjustment signal according to the deviation data of the real-time displacement and the target displacement; and controlling a pressure regulating component to dynamically adjust the spring pre-tightening force, so as to realize pressure closed-loop control. The device comprises a mechanical execution unit, a data detection unit and a control processing unit, and the units work cooperatively to realize closed-loop control of pressure regulation by detecting the medium pressure and the piston shaft displacement in real time and dynamically adjusting the spring pre-tightening force, and the device has the advantages of automatic calibration, reduction of manual intervention and improvement of control precision.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pilot valves, and particularly relates to a pilot valve control method and device based on automatic pressure adjustment through data detection BACKGROUND

[0002] In a fluid pressure control system in the industrial field of petroleum and chemical engineering, a pilot valve, as a core element for realizing accurate regulation of medium pressure, is widely used in key scenes such as high-pressure oil and gas pipeline transportation and reaction kettle pressure stabilization. The traditional pilot valve relies on mechanical spring pre-tightening force to set the pressure threshold. However, in long-term operation, the spring pre-tightening force will decay due to mechanical fatigue, medium scouring or temperature change, resulting in deviation of the actual control pressure from the set value. At this time, the spring pre-tightening force needs to be calibrated by stopping the machine, disassembling the valve body and manually adjusting the bolt, which not only wastes time and effort and interrupts the production process, but also significantly affects the adjustment accuracy of the operator, especially in high-pressure, flammable and explosive oil and gas environments, where manual intervention delay can easily cause overpressure leakage risk.

[0003] These problems seriously restrict the application effect of the pilot valve in the precise fluid control system, and therefore, it is urgent to provide a pilot valve control method and device based on automatic adjustment of spring pre-tightening force through real-time data detection, to realize self-adaptive calibration and dynamic balance of the pressure of the industrial pipeline system, and improve the automation level and operation reliability of the fluid control system. SUMMARY

[0004] The present application aims to provide a pilot valve control method and device based on automatic pressure adjustment through data detection, which has the advantages of real-time automatic adjustment of spring pre-tightening force, avoidance of manual intervention and improvement of pressure control accuracy.

[0005] The present application provides a pilot valve control method based on automatic pressure adjustment through data detection, and the technical solution is as follows:

[0006] The pilot valve comprises a valve body, a pressure regulating assembly, a spring assembly, a pressure sensor and a displacement sensor; the pressure regulating assembly comprises a piston and a piston shaft; the spring assembly comprises a spring acting on the piston and a pressure regulating component for adjusting the spring pre-tightening force; the pressure sensor is used to acquire the real-time medium pressure in the valve body, and the displacement sensor is used to detect the real-time displacement of the piston shaft; the method comprises:

[0007] acquiring the real-time medium pressure of the valve body in real time through the pressure sensor;

[0008] acquiring the real-time displacement of the piston shaft in real time through the displacement sensor;

[0009] determining the target displacement of the piston shaft based on the real-time medium pressure;

[0010] determining displacement deviation data based on the real-time displacement and the target displacement;

[0011] determining adjustment data based on the displacement deviation data in the case that it is determined that adjustment of the pressure regulating component is required according to the displacement deviation data;

[0012] controlling the pressure regulating component to adjust the pre-tightening force of the spring based on the adjustment data.

[0013] Further, the application also proposes querying the stored pressure-displacement correlation curve, and mapping the corresponding piston shaft displacement amount as a target displacement amount according to the real-time medium pressure; wherein the pressure-displacement correlation curve is determined through experimental calibration or theoretical calculation, and is used to represent the corresponding relationship between the steady-state pressure and the piston shaft equilibrium position.

[0014] Further, the application also proposes obtaining a displacement deviation value according to the difference between the real-time displacement amount and the target displacement amount; and performing low-pass filtering processing on the displacement deviation value to obtain displacement deviation data.

[0015] Further, the application also proposes determining whether the absolute value of the displacement deviation data is greater than a set adjustment threshold value; and if it is greater than the adjustment threshold value, determining the adjustment direction according to the positive and negative of the displacement deviation data, and determining the adjustment amplitude according to the absolute value of the displacement deviation data.

[0016] Further, the application also proposes generating a pulse width control signal according to the adjustment data to drive the pressure regulating component, so as to adjust the pre-tightening force of the spring.

[0017] Further, the application also proposes comparing the collected real-time medium pressure and real-time displacement amount with a set pressure-displacement correlation curve threshold range; if the detection data deviates from the threshold range for more than a set time or number of times, an alarm signal is triggered, and the pressure regulating component is controlled to drive the piston shaft to move to a safe position.

[0018] Further, the application also proposes a pilot valve device, comprising a mechanical execution unit, a data detection unit and a control processing unit; the mechanical execution unit comprises:

[0019] a valve body, an inner cavity of which is provided with a piston containing cavity and a modulation cavity which are in communication with each other through a piston shaft hole;

[0020] a pressure regulating assembly for adjusting the medium pressure in the valve body, comprising: a piston slidingly arranged in the piston containing cavity, a pressure stabilizing cavity assembly arranged in the modulation cavity, and a piston shaft axially movably arranged in the inner cavity of the valve body; one end of the piston shaft is connected to the piston, and the other end extends into the pressure stabilizing cavity in the pressure stabilizing cavity assembly; and

[0021] a spring assembly comprising a spring and a pressure regulating component; the spring is clamped between the piston and the pressure regulating component, and is used to provide a pre-tightening force for the piston, and the pressure regulating component is used to adjust the pre-tightening force of the spring.

[0022] The sealing assembly is installed at the bottom of the piston accommodating cavity and is provided with a through hole through which the piston shaft passes;

[0023] The data detection unit comprises a pressure sensor and a displacement sensor, the pressure sensor is arranged at the piston accommodating cavity to obtain the real-time medium pressure in the valve body, and the displacement sensor is arranged at the corresponding end position of the piston shaft in the pressure stabilizing cavity in the pressure stabilizing cavity assembly to detect the real-time displacement of the piston shaft.

[0024] The control processing unit is in signal connection with the data detection unit and the pressure regulating component, comprises a memory, a processor and a computer program stored in the memory and capable of running on the processor, and the processor realizes the above method when executing the computer program.

[0025] Further, the pressure regulating component comprises an adjusting bolt and a micro stepping motor, the micro stepping motor drives the adjusting bolt to rotate through a transmission mechanism to change the compression amount of the spring.

[0026] Further, the piston shaft comprises a cut-off section and a flow-through section, and passes through the piston shaft hole; the outer diameter of each part of the piston shaft is smaller than the hole diameter of the piston shaft hole to form a medium flow-through channel; and the cut-off section has a variable diameter structure matched with the through hole of the sealing assembly, used to adjust the cross-sectional area of the medium flow-through channel through the change of the axial movement of the piston shaft to form an adjustable medium flow-through channel; when the piston shaft is located at the safe position, the largest diameter part of the cut-off section is in sealing cooperation with the through hole to block the medium flow-through; when the piston shaft is located at the working position, an annular flow-through gap is formed between the cut-off section and the through hole, and the cross-sectional area of the annular flow-through gap changes with the displacement of the piston shaft.

[0027] The application has the advantages that the provided pilot valve control method and device based on data detection automatic pressure regulation can realize closed-loop control of pressure deviation by real-time detection of medium pressure and piston shaft displacement and dynamic adjustment of spring pre-tightening force, and has the advantages of automatic calibration, reduction of manual intervention and improvement of control precision. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed to be used in the embodiments or prior art description will be briefly introduced.

[0029] Figure 1 The figure is a control method step schematic diagram of the application embodiment;

[0030] Figure 2 The figure is a device structure schematic diagram of the application embodiment;

[0031] Figure 3 The figure is a valve body cross-sectional structure schematic diagram;

[0032] Figure 4 The figure is a piston shaft structure schematic diagram.

[0033] In the drawings:

[0034] 10, valve body; 11, piston accommodating cavity; 12, modulating cavity; 13, piston shaft hole; 20, piston; 30, pressure stabilizing cavity assembly; 40, piston shaft; 41, intercepting section; 411, thin shaft section; 412, thick shaft section; 423, tapered surface; 42, flow passing section; 44, medium flow passing channel; 50, sealing assembly; 60, spring; 70, pressure regulating component; 71, micro stepping motor; 72, adjusting bolt; 80, data detecting unit; 81, pressure sensor; 82, displacement sensor; 90, control processing unit. DETAILED DESCRIPTION

[0035] The technical solutions in the present application will be described clearly and completely below in combination with the drawings in the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. The components of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0036] It should be noted that: similar reference numbers and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. Meanwhile, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0037] In the conventional fluid pressure control system, the pilot valve relies on the mechanical spring pre-tightening force to set the pressure threshold. Due to the attenuation of the spring pre-tightening force in long-term operation, the actual control pressure deviates from the set value. Manual calibration needs to interrupt the production process, and the adjustment accuracy is limited by the operation experience, and there is a safety risk in the high-pressure flammable environment. The prior art lacks a double-parameter closed-loop control model of pressure and piston shaft displacement, and cannot establish a spring pre-tightening force dynamic compensation mechanism, so that the system cannot respond to medium pressure fluctuations in real time, causing regulation lag and pressure oscillation.

[0038] The spring pre-tightening force of the traditional pilot valve is fixed, and the piston shaft displacement cannot be dynamically adjusted following the pressure change. When the medium pressure suddenly rises, the piston shaft is limited by the spring reaction force and cannot quickly move to the balance position, causing the internal pressure of the valve body to overshoot. At this time, the sealing assembly bears abnormal stress, the annular flow gap cross-sectional area adjustment is out of alignment, the medium flow rate exceeds the design range, and the pipeline pressure continues to oscillate. Under such working conditions, the safety valve is frequently triggered by mistake, and the system is forced to enter a protective shutdown state. If the above problems are not solved, the pressure control deviation will cause the pipeline system to frequently start and stop, shortening the service life of the key components. In extreme working conditions, the pressure regulation lag may exceed the safety valve response threshold, directly causing structural damage to the pipeline pressure-bearing components.

[0039] In the face of the above problems, the present application first considers how to realize the dynamic compensation of the spring pre-tightening force to eliminate the pressure control deviation. The traditional scheme only relies on pressure feedback for alarm or simple adjustment, but the pressure change and the piston shaft displacement are associated with a lag, and a single parameter cannot accurately reflect the dynamic balance state of the system. If the spring pre-tightening force is adjusted only based on the pressure deviation, the adjustment action may be frequently triggered due to frequent pressure fluctuations, causing excessive wear of the actuator. If only a displacement sensor is used to monitor the piston shaft position, although the spring deformation can be directly reflected, the dynamic influence of the medium pressure change on the displacement demand cannot be associated.

[0040] To this end, the present application proposes to fuse pressure and displacement data to form a closed-loop control logic. By mapping the target displacement amount in real time with the medium pressure, a steady-state correspondence between pressure and displacement is established, and the pre-tightening force adjustment requirement is combined with the real-time displacement deviation. Among them, the pressure data is used to set the displacement reference, and the displacement data is used to feedback the actual adjustment effect, and the combination of the two can avoid the limitations of single parameter control. For example, when the medium pressure suddenly rises, the target displacement amount is dynamically adjusted with the pressure change, the system quickly identifies the lack of spring pre-tightening force through the displacement deviation, and then drives the pressure regulating component to compensate the pre-tightening force, so that the piston shaft moves to a new balance position, avoiding pressure oscillation and regulation lag.

[0041] To this end, as shown in Figure 1 and Figure 2 The present application proposes a pilot valve control method based on data detection automatic pressure regulation, the pilot valve comprising a valve body 10, a pressure regulating assembly, a spring assembly, a pressure sensor 81 and a displacement sensor 82; the pressure regulating assembly comprises a piston 20 and a piston shaft 40; the spring assembly includes a spring 60 acting on the piston 20 and a pressure regulating component 70 for adjusting the spring pre-tightening force; the pressure sensor 81 is used to obtain the real-time medium pressure in the valve body 10, and the displacement sensor 82 is used to detect the real-time displacement amount of the piston shaft 40; Figure 1 A schematic flow chart of a pilot valve control method based on data detection automatic pressure regulation provided by the present application is shown, the method comprising:

[0042] The real-time medium pressure of the valve body 10 is obtained in real time through the pressure sensor 81;

[0043] The real-time displacement of the piston shaft 40 is obtained in real time through the displacement sensor 82;

[0044] The target displacement of the piston shaft 40 is determined based on the real-time medium pressure;

[0045] The displacement deviation data is determined based on the real-time displacement and the target displacement;

[0046] When it is determined according to the displacement deviation data that the pressure regulating component 70 needs to be adjusted, the adjustment data is determined based on the displacement deviation data;

[0047] The adjustment data is used to control the pressure regulating component 70 to adjust the pre-tightening force of the spring 60.

[0048] It can be understood that the pressure regulating assembly including the piston 20 and the piston shaft 40 refers to changing the cross-sectional area of the medium flow passage 44 through the axial movement of the piston 20 in the valve body 10, so as to adjust the medium pressure, which can be specifically realized by using a hydraulic cylinder structure or a pneumatic actuator. The piston shaft 40 is rigidly connected with the piston 20, and transmits the movement of the piston 20 to the pressure regulating component 70. The spring assembly including the spring 60 acting on the piston 20 and the pressure regulating component 70 for adjusting the pre-tightening force of the spring refers to adjusting the initial force of the spring 60 on the piston 20 by changing the compression amount of the spring 60, which can be specifically realized by using a helical spring 60 cooperating with a threaded adjusting mechanism or an electric push rod structure. The pressure regulating component 70 changes the compression amount of the spring through mechanical transmission or electrical signal driving. The pressure sensor 81 for obtaining the real-time medium pressure in the valve body 10 refers to converting the physical pressure signal into an electrical signal through a pressure-sensitive element, which can be specifically realized by using a piezoelectric sensor. The real-time medium pressure is monitored and transmitted to the control processing unit 90. The displacement sensor 82 for detecting the real-time displacement of the piston shaft 40 refers to obtaining the position information of the piston shaft 40 through a non-contact measurement technology, which can be specifically realized by using a magnetostrictive displacement sensor 82 or a grating encoder. The movement state of the piston shaft 40 is fed back to the control processing unit 90 in real time.

[0049] It can be understood that S3 refers to calculating the ideal displacement value corresponding to the current pressure according to the preset pressure-displacement mapping relationship, which can be specifically realized by using a table lookup method or an interpolation algorithm, and establishing a steady-state balance model of pressure and displacement.

[0050] S4 refers to generating an error signal by comparing the difference between the actual displacement and the target displacement, which can be specifically realized by using a digital signal processing algorithm, and quantifying the position deviation of the piston shaft 40.

[0051] Wherein, S5, based on displacement deviation data to determine the adjustment data is to generate control instructions of the pressure regulating component 70 according to the error size and direction, which can be realized by using proportional integral derivative algorithm or fuzzy control algorithm, and dynamically adjusts the spring pre-tightening force to eliminate the displacement deviation.

[0052] Wherein, S6, based on the adjustment data to control the pressure regulating component 70 to adjust the pre-tightening force of the spring 60 is to convert the control instructions into mechanical actions of the pressure regulating component 70, which can be realized by using step motor 71 to drive the screw pair to rotate or servo motor to drive the linear push rod to move, so as to realize the accurate adjustment of the spring compression amount.

[0053] The working process and principle of the present application are as follows: the control method first acquires the medium pressure in the valve body 10 through the pressure sensor 81 in real time, and simultaneously acquires the displacement amount of the piston shaft 40 through the displacement sensor 82 in real time. Based on the acquired real-time medium pressure, the target displacement amount of the piston shaft 40 is determined. Then, the actual displacement amount is compared with the target displacement amount to determine the displacement deviation data. According to the displacement deviation data, it is determined whether the pressure regulating component 70 needs to be adjusted, and if adjustment is needed, the specific adjustment data is determined based on the displacement deviation data. Finally, the pre-tightening force of the spring 60 is adjusted by the pressure regulating component 70 according to the adjustment data.

[0054] This double-parameter closed-loop control logic fuses pressure and displacement data, sets displacement reference through pressure data, and feeds back actual adjustment effect through displacement data. When the medium pressure changes, the system can quickly identify whether the spring pre-tightening force is sufficient, and drive the pressure regulating component 70 to compensate, so that the piston shaft 40 moves to a new balance position. This way avoids the limitations of single-parameter control, and can more accurately respond to system pressure changes.

[0055] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0056] The pilot valve device includes a valve body 10, a pressure regulating assembly, a spring assembly, a pressure sensor 81 and a displacement sensor 82. The valve body 10 is provided with a piston accommodating cavity 11 and a modulation cavity 12, which are communicated through a piston shaft hole 13. The pressure regulating assembly includes a piston 20 slidingly arranged in the piston accommodating cavity 11, and an axially movable piston shaft 40. One end of the piston shaft 40 is connected to the piston 20, and the other end extends into the pressure stabilizing cavity. The spring assembly includes a spring 60 and a pressure regulating component 70, and the spring 60 is clamped between the piston 20 and the pressure regulating component 70 to provide pre-tightening force for the piston 20.

[0057] The pressure sensor 81 is installed at the piston accommodating cavity 11 for acquiring real-time medium pressure in the valve body 10. The displacement sensor 82 is arranged in the pressure stabilizing cavity and corresponds to the end position of the piston shaft 40 for detecting the real-time displacement of the piston shaft 40. The control processing unit 90 is in signal connection with the data detection unit 80 and the pressure regulating component 70, and includes a memory, a processor and a computer program executable on the processor.

[0058] The specific steps of the control method are as follows:

[0059] Firstly, the pressure sensor 81 collects real-time medium pressure data in the valve body 10, and the displacement sensor 82 synchronously collects displacement data of the piston shaft 40. These data are transmitted to the control processing unit 90 for processing.

[0060] The control processing unit 90 determines the target displacement of the piston shaft 40 based on the real-time medium pressure. Specifically, the real-time pressure can be mapped to the corresponding target displacement by querying the pre-stored pressure-displacement correlation curve.

[0061] Then, the control processing unit 90 compares the real-time displacement with the target displacement to calculate the displacement deviation. To eliminate the influence of transient fluctuations, the displacement deviation can be subjected to low-pass filtering to obtain stable displacement deviation data.

[0062] According to the displacement deviation data, the control processing unit 90 judges whether the pressure regulating component 70 needs to be adjusted. The judgment method can set an adjustment threshold, and the adjustment is triggered when the absolute value of the displacement deviation exceeds the threshold. The determination of the adjustment data includes the adjustment direction and the adjustment amplitude, which are determined by the positive and negative of the displacement deviation and the absolute value, respectively.

[0063] Finally, the control processing unit 90 generates a control signal according to the adjustment data to drive the pressure regulating component 70 to adjust the spring pre-tightening force. The pressure regulating component 70 can adopt the mode of micro-step motor 71 driving adjustment bolt 72 to realize accurate adjustment.

[0064] Through the above scheme, the dynamic compensation of the spring pre-tightening force of the pilot valve is realized, and the pressure control deviation is effectively eliminated. Through the closed-loop control logic of the fusion of pressure and displacement data, the system can quickly respond to the medium pressure fluctuation, avoiding the adjustment lag and pressure oscillation problems in the traditional scheme. In the application scenarios such as high-pressure oil and gas long-distance pipeline, the scheme can effectively cope with the pressure fluctuation caused by factors such as compressor start-stop and environmental temperature change, and maintain the stable operation of the system. In addition, the automatic adjustment mechanism reduces the need for manual intervention and reduces the safety risk in the high-pressure flammable environment. Overall, the application improves the application effect of the pilot valve in the precision fluid control system and improves the automation level and operation reliability of the industrial pipeline system pressure control.

[0065] Further, the application proposes querying the stored pressure-displacement correlation curve, and mapping the corresponding piston shaft 40 displacement as a target displacement according to the real-time medium pressure; the pressure-displacement correlation curve is determined through experimental calibration or theoretical calculation, and is used to represent the corresponding relationship between the steady pressure and the piston shaft 40 equilibrium position.

[0066] The generation of the pressure-displacement correlation curve includes two ways of experimental calibration and theoretical calculation. The experimental calibration records the actual equilibrium position of the piston shaft 40 under different steady pressures to fit a continuous curve of discrete data points; for example, a step pressure loading method is used to apply a steady pressure in the range of 0-10 MPa at an interval of 1 MPa, and the equilibrium position of the piston shaft is recorded at each pressure point and a cubic polynomial curve is fitted. The theoretical calculation is based on the mechanical system mechanics model to deduce the mathematical relationship between pressure and displacement to construct the curve. For example, the theoretical calculation of the pressure-displacement correlation curve is based on the force balance equation of the piston:

[0067]

[0068] In the formula, P P is the medium pressure (Pa), A A is the effective area of the piston (m²), k K is the spring stiffness coefficient (N / m),

[0069] x 0 is the initial compression amount of the spring (mm), x X is the displacement of the piston shaft (mm). The mapping relationship between pressure and displacement can be obtained by deformation:

[0070]

[0071] The equation represents the equilibrium position of the piston shaft under the steady pressure, and the pressure-displacement correlation curve can be generated accordingly. In the querying process, the real-time medium pressure is input into the stored curve database, and the corresponding target displacement is matched through interpolation or table lookup.

[0072] Specifically, when the real-time medium pressure is collected by the pressure sensor 81, the control processing unit 90 calls the pre-stored pressure-displacement correlation curve, takes the current pressure value as the input parameter, locates to the corresponding point along the horizontal axis of the curve, and the output of the vertical axis is the target displacement amount. For example, in the experimental calibration scene, the pilot valve is pre-applied with a steady-state pressure of a step-by-step increase on the pressure test bench, and the static position of the piston shaft 40 reaching force balance under each pressure step is recorded, and a smooth curve is generated by polynomial fitting; in the theoretical calculation scene, according to the spring 60 stiffness coefficient, the effective area of the piston 20 and the medium pressure balance equation, the analytical expression of the pressure and displacement is established to generate the curve. The target displacement amount determined by the above-mentioned method can accurately reflect the theoretical balance position of the piston shaft 40 under a certain pressure, and provide a reliable reference for subsequent displacement deviation calculation and pressure regulation control, and eliminate the mapping error caused by experience estimation or dynamic interference.

[0073] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0074] The pressure-displacement correlation curve is determined by experimental calibration or theoretical calculation, and is used to characterize the corresponding relationship between the steady-state pressure and the balance position of the piston shaft 40. Specifically, a high-precision pressure sensor 81 and a displacement sensor 82 can be installed on the pilot valve device, and the balance position of the piston shaft 40 under different steady-state pressures can be recorded. A series of corresponding data points of pressure and displacement are obtained through multiple tests, and then the pressure-displacement correlation curve is fitted by using the least square method.

[0075] For example, 5 different steady-state pressure points can be selected for testing, which are 1 MPa, 3 MPa, 5 MPa, 7 MPa and 9 MPa. Each pressure point is tested 3 times, and the balance position of the piston shaft 40 is recorded. The obtained 15 groups of data points are input into a computer, and the data processing and curve fitting are performed by using the curve fitting toolbox of MATLAB software. The fitted pressure-displacement correlation curve can be expressed by a quadratic polynomial: y = ax^2 + bx + c, where y represents the displacement of the piston shaft 40, x represents the steady-state pressure, and a, b and c are fitting coefficients.

[0076] Further, the fitted pressure-displacement correlation curve is stored in the memory of the control processing unit 90. In actual operation, after the real-time medium pressure of the valve body 10 is obtained by the pressure sensor 81 in real time, the pressure value is substituted into the stored correlation curve equation, and the corresponding displacement amount of the piston shaft 40 is calculated, which is the target displacement amount.

[0077] Therefore, based on the pressure-displacement correlation curve determined by experimental calibration or theoretical calculation, the real-time medium pressure can be accurately mapped to the target displacement amount of the piston shaft 40, which provides a reliable reference for the subsequent displacement deviation calculation and pressure regulation control.

[0078] Through the above technical solutions, the present application realizes accurate mapping between real-time medium pressure and target displacement amount of the piston shaft 40. Specifically, through the pre-established pressure-displacement correlation curve, the ideal equilibrium position of the piston shaft 40 under the current pressure can be quickly and accurately determined. This data-driven method avoids complex theoretical calculations, improving the efficiency and accuracy of target displacement amount determination. At the same time, since the correlation curve is established based on experimental data of the actual device or an accurate theoretical model, it can better reflect the actual working characteristics of a specific pilot valve, improving the adaptability and reliability of the control system. This provides a reliable reference benchmark for subsequent displacement deviation calculation and pressure regulation control, helping to achieve more accurate pressure regulation and system stability control.

[0079] Further, the present application proposes to determine displacement deviation data based on real-time displacement amount and target displacement amount, including obtaining displacement deviation value according to the difference between real-time displacement amount and target displacement amount, and obtaining displacement deviation data by low-pass filtering the displacement deviation value.

[0080] wherein the displacement deviation value e ( t ) is defined as: , wherein

[0081] is the real-time displacement amount, is the target displacement amount. The low-pass filtering is realized by configuring a Butterworth filter with a cutoff frequency lower than the system inherent frequency, the order of the filter is set to two, and the cutoff frequency is set to 10-50 Hz according to the response speed of the piston shaft 40 movement; the low-pass filter transfer function expression

[0082] , the cutoff angular frequency , f is the cutoff frequency (Hz), and the displacement deviation data after the low-pass filtering is transmitted to the control processing unit 90 through an analog-to-digital converter.

[0083] Specifically, the analog signal of the position of the piston shaft 40 collected by the displacement sensor 82 is amplified by the signal conditioning circuit, and the analog signal output by the digital-to-analog converter of the target displacement amount digital signal is input into the subtracter together to generate a raw displacement deviation signal containing high-frequency noise. The signal is input into a second-order Butterworth low-pass filter composed of an operational amplifier and an RC element to filter out noise components with a frequency higher than the cutoff frequency. For example, in the scene where the high-pressure pipeline pressure fluctuates frequently, setting the cutoff frequency to 20 Hz can effectively suppress the high-frequency micro-vibration noise of the piston shaft 40 caused by fluid pulsation, and retain the low-frequency effective signal reflecting the true displacement deviation. The filtered displacement deviation data is input into the control algorithm module after being converted into digital signals, as an input parameter for subsequent adjustment decisions, to avoid false adjustment of the pressure regulating component 70 caused by noise interference and ensure stable operation of the system.

[0084] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0085] When determining the displacement deviation data based on the real-time displacement amount and the target displacement amount, first, the displacement deviation value is obtained according to the difference between the real-time displacement amount and the target displacement amount. For example, when the real-time displacement amount is 5 mm and the target displacement amount is 6 mm, the displacement deviation value is -1 mm. Further, the displacement deviation value is subjected to low-pass filtering to obtain the displacement deviation data. Specifically, a Butterworth low-pass filter can be used to process the displacement deviation value to filter out high-frequency noise. In this way, more smooth displacement deviation data is obtained, reducing the influence of transient interference on the control system.

[0086] Through the above technical scheme, the present application can effectively filter out high-frequency noise in the displacement deviation value and obtain more stable and reliable displacement deviation data. In this way, the anti-interference ability and control accuracy of the pilot valve control system are improved, false adjustment caused by transient interference is avoided, and stable operation of the pilot valve is ensured. Further, through low-pass filtering, the frequency of adjustment of the control system is reduced, the service life of the pressure regulating component 70 is prolonged, and the reliability and durability of the entire pilot valve system are improved.

[0087] Further, the present application proposes to determine whether the absolute value of the displacement deviation data is greater than a set adjustment threshold. If it is greater than the adjustment threshold, the adjustment direction is determined according to the positive and negative of the displacement deviation data, and the adjustment amplitude is determined according to the absolute value of the displacement deviation data.

[0088] Among them, the setting of the adjustment threshold is used to filter small deviations or transient fluctuations to avoid invalid adjustment actions; the adjustment direction is determined by the positive and negative signs of the displacement deviation data, and a positive deviation corresponds to an adjustment direction of increasing the pre-tightening force, and a negative deviation corresponds to an adjustment direction of reducing the pre-tightening force; the adjustment amplitude is positively correlated with the absolute value of the displacement deviation, the larger the deviation, the larger the adjustment amplitude, and the smaller the deviation, the smaller the adjustment amplitude.

[0089] Specifically, the displacement deviation data is low-pass filtered, and its absolute value is compared with a preset adjustment threshold. When the absolute value exceeds the adjustment threshold, it is determined that an adjustment action needs to be performed. At this time, the rotation direction of the pressure regulating component 70 is determined according to the positive and negative signs of the deviation value. For example, a positive deviation drives the pressure regulating component 70 to move in the direction of the compression spring 60, and a negative deviation drives the pressure regulating component 70 to move in the direction of the release spring 60. The adjustment amplitude is determined according to the difference between the absolute value of the deviation and the threshold value or a preset segmented interval. For example, when the absolute value of the deviation exceeds the threshold value but is less than twice the threshold value, a first-level adjustment amplitude is adopted, and when it exceeds twice the threshold value, a second-level adjustment amplitude is adopted. Through the joint control of the threshold value judgment and the direction amplitude, it is ensured that the adjustment action is triggered only under necessary conditions, and the adjustment amount accurately matches the actual demand, thereby reducing the adjustment frequency and improving the control accuracy.

[0090] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0091] It is determined whether the absolute value of the displacement deviation data is greater than a set adjustment threshold. If it is greater than the adjustment threshold, the adjustment direction is determined according to the positive and negative of the displacement deviation data, and the adjustment amplitude is determined according to the absolute value of the displacement deviation data.

[0092] Specifically, the adjustment threshold can be set to 0.1 mm. When it is detected that the absolute value of the displacement deviation data is greater than 0.1 mm, the adjustment operation is triggered. If the displacement deviation data is positive, it indicates that the actual displacement is greater than the target displacement, and the spring pre-tightening force needs to be increased; if it is negative, the spring pre-tightening force needs to be reduced. The adjustment amplitude can be classified according to the absolute value of the displacement deviation data, for example, 0.1-0.3 mm corresponds to a first-level adjustment, 0.3-0.5 mm corresponds to a second-level adjustment, and 0.5 mm or more corresponds to a third-level adjustment. Each level of adjustment corresponds to different driving parameters of the pressure regulating component 70.

[0093] Through the above technical scheme, the present application can flexibly adjust the spring pre-tightening force according to the size and positive and negative of the displacement deviation data, avoid system fluctuations caused by frequent small adjustments, and at the same time ensure fast response in the case of large deviation. This hierarchical adjustment strategy can improve system stability while ensuring adjustment accuracy, effectively solving the problems of traditional pilot valve adjustment lag, pressure oscillation, etc.

[0094] Further, the present application proposes to control the pressure regulating component 70 to adjust the pre-tightening force of the spring 60 based on adjustment data, including: generating a pulse width control signal according to the adjustment data to drive the pressure regulating component 70, thereby adjusting the pre-tightening force of the spring 60.

[0095] Wherein, the pulse width control signal establishes a linear mapping relationship with the adjustment amplitude through a preset pulse step, and the pulse width is positively correlated with the absolute value of the displacement deviation data. Specifically, the relationship between the adjustment data and the pulse signal is:

[0096]

[0097] wherein N is the number of pulses, Δ x is the adjustment amount of spring compression (m), p is the pitch of the adjusting bolt (m), i is the reduction ratio of the transmission mechanism.

[0098] The duty cycle D of the pulse width modulation signal is associated with the adjustment direction:

[0099]

[0100] wherein, D 0 is the base duty cycle (typical value is 0.5), k is the duty cycle adjustment coefficient (unit: 1 / mm), |Δ x | is the absolute value of the displacement deviation (mm). The adjustment direction is determined by the positive and negative signs of the displacement deviation data: a positive deviation corresponds to an increase in spring compression, driving the pressure regulating component to move in the screw-in direction; a negative deviation corresponds to a decrease in spring compression, driving the pressure regulating component to move in the screw-out direction.

[0101] The pressure regulating component 70 includes a transmission combination of a micro stepping motor 71 and an adjusting bolt 72. After receiving the pulse signal, the micro stepping motor 71 drives the adjusting bolt 72 to rotate through the reduction gear set. Each pulse signal corresponds to a fixed rotation angle of the adjusting bolt 72, and the number of pulses determines the axial displacement of the adjusting bolt 72, thereby changing the spring compression. For example, when the absolute value of the displacement deviation data reaches twice the adjustment threshold, a control signal containing twenty pulses is generated, driving the adjusting bolt 72 to rotate five degrees, increasing the spring preload by three Newtons.

[0102] Specifically, the control processing unit 90 converts the displacement deviation data into a pulse width modulation signal, and the number of pulses in the signal is proportional to the adjustment amplitude. After receiving the pulse signal, the micro stepping motor 71 converts the rotary motion into the axial linear motion of the adjusting bolt 72 through the transmission mechanism. For each fixed angle of rotation of the adjusting bolt 72, its end pushes the spring 60 seat to produce a corresponding displacement increment, and the spring compression changes accordingly. This method achieves precise fine tuning of mechanical components through discrete pulse control, avoiding the cumulative error of inertia caused by continuous driving. For example, when a positive displacement deviation is detected, the control signal drives the adjusting bolt 72 to screw in to increase the spring compression; when a negative deviation is detected, the control signal drives the adjusting bolt 72 to screw out to reduce the compression. The corresponding relationship between pulse width and adjustment amplitude is calibrated through experiments, ensuring that the preload change corresponding to each pulse does not exceed the error threshold allowed by the system.

[0103] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0104] When the pre-tightening force of the spring 60 is adjusted by the pressure regulating component 70 based on the adjustment data, first, a pulse width control signal is generated according to the adjustment data. Specifically, the processor in the control processing unit 90 executes a computer program to convert the adjustment data into a corresponding pulse width modulation signal. For example, when the adjustment data is positive, a pulse signal of forward rotation is generated, and when the adjustment data is negative, a pulse signal of reverse rotation is generated. The greater the absolute value of the adjustment data, the greater the pulse width generated.

[0105] Further, the pulse width modulation signal generated is sent to the micro stepping motor 71 in the pressure regulating component 70. Thus, the micro stepping motor 71 drives the adjusting bolt 72 to rotate according to the received pulse signal. Specifically, the stepping motor 71 drives the adjusting bolt 72 to rotate forward or reverse through a gear transmission mechanism, and the rotation angle is determined by the width of the pulse signal.

[0106] The rotation movement of the adjusting bolt 72 is converted into axial displacement, thereby changing the compression amount of the spring 60. For example, when the adjusting bolt 72 is rotated clockwise, the bolt moves downward to increase the spring compression amount; when it is rotated counterclockwise, the bolt moves upward to decrease the spring compression amount. As a preferred embodiment, the thread pitch of the adjusting bolt 72 is 1 mm, the step angle of the stepping motor 71 is 1.8°, and the minimum adjustment precision of 0.025 μm is achieved through a reduction ratio of 200:1 transmission to the adjusting bolt 72.

[0107] Through the above technical solutions, the present application realizes accurate automatic adjustment of the pre-tightening force of the pilot valve spring. Thus, the inefficiency and inaccuracy of the traditional manual adjustment method are avoided, and the pressure control precision and response speed of the pilot valve are improved. Further, the automatic adjustment process does not need to be stopped and disassembled, reducing the production interruption time and improving the continuity and reliability of system operation. In addition, real-time compensation of the spring pre-tightening force is realized through closed-loop control, effectively solving the problem of pressure deviation caused by spring 60 fatigue in long-term operation, and ensuring the stable performance of the pilot valve under various working conditions.

[0108] Further, the present application proposes to compare the collected real-time medium pressure and real-time displacement amount with the set pressure-displacement correlation curve threshold range; if the detection data deviates from the threshold range for more than a set time or number of times, an alarm signal is triggered, and the pressure regulating component 70 is controlled to drive the piston shaft 40 to move to a safe position.

[0109] The pressure-displacement correlation curve threshold range is determined by experiment calibration and includes the upper and lower limits of pressure and the corresponding displacement amount fluctuation interval. In the comparison process, the real-time medium pressure and displacement amount need to meet the pressure threshold and displacement threshold at the same time, and any parameter exceeding the range is considered to deviate.

[0110] The determination condition that the detection data deviates from the threshold range is:

[0111]

[0112] wherein, P ( t ), x ( t ) is the real-time detection value, P ref ( t ), x ref ( t ) is the theoretical value of the pressure-displacement correlation curve, Δ P , Δ x is the set threshold value (such as Δ P = 0.5 MPa, Δ x = 0.1 mm). If the above condition lasts for a time t > t thr or appears continuously for a number of times n > n thr , the safety mechanism is triggered.

[0113] The set time t thr or the number of times n thr is pre-configured according to the system response speed and the process safety requirement, for example, the set time t thr is 5 seconds, and the number of times n thr is 3 continuous detection deviations. The alarm signal is sent through an audible and light device or a remote monitoring system, and the safety position is defined as the position where the maximum diameter part of the shut-off section 41 is completely matched with the through hole of the sealing assembly 50.

[0114] Specifically, the pressure sensor 81 continuously monitors the medium pressure in the valve body 10, and the displacement sensor 82 collects the displacement of the piston shaft 40 in real time. The control processing unit 90 synchronously checks the two sets of data against the stored pressure-displacement correlation curve threshold range. When the medium pressure exceeds the set pressure threshold or the displacement deviates from the corresponding displacement threshold, the system starts a timer or a counter. If the deviation state is not eliminated within the set time or the cumulative number of times reaches the set number of times, it is determined that the abnormality is not recoverable, and an alarm signal is immediately triggered. At the same time, the control processing unit 90 sends an emergency control instruction to the pressure regulating component 70 to drive the piston shaft 40 to move to a safe position, so that the maximum diameter part of the intercepting section 41 forms a sealing fit with the through hole of the sealing assembly 50, completely blocking the medium flow passage 44, and avoiding equipment overload or medium leakage caused by continuous pressure abnormality. In this process, the miniature stepper motor 71 rapidly rotates the adjusting bolt 72 through the transmission mechanism to change the spring compression amount, forcing the piston shaft 40 to reset to the safe position.

[0115] As a preferred embodiment, the scheme of the present application is implemented as follows:

[0116] The collected real-time medium pressure and real-time displacement are compared with the set pressure-displacement correlation curve threshold range. If the detected data deviates from the threshold range for more than a set time or number of times, an alarm signal is triggered, and the pressure regulating component 70 is controlled to drive the piston shaft 40 to move to a safe position.

[0117] Specifically, upper and lower threshold values of the pressure-displacement correlation curve can be set to form an interval that allows fluctuations. For example, for a certain type of pilot valve, ±5% of the pressure-displacement correlation curve can be set as the threshold range. The real-time collected pressure and displacement data are compared with the threshold range.

[0118] Further, a duration threshold, such as 10 seconds, or a continuous deviation number threshold, such as 5 times, can be set. When it is detected that the actual data continuously deviates from the threshold range for more than 10 seconds, or 5 consecutive samples deviate from the threshold range, the system determines that an abnormality has occurred.

[0119] Thus, an alarm signal can be triggered, which can be in the form of audible and visual alarms or remote notification, to remind the operator to pay attention to the system status. At the same time, the pressure regulating component 70 is controlled to drive the piston shaft 40 to move to a pre-set safe position, for example, to completely close the flow passage to prevent potential pressure out-of-control risks.

[0120] By the technical solution, real-time monitoring of the operation state of the pilot valve and timely response to abnormal conditions are achieved. By setting reasonable threshold ranges and trigger conditions, false positives caused by transient fluctuations are avoided, and the reliability of the system is improved. When persistent abnormalities are detected, safety measures can be automatically taken, effectively preventing the risk of pressure loss of control caused by valve failure. This active early warning and automatic protection mechanism greatly improves the safety performance of the pilot valve in high-pressure, flammable and explosive environments, providing more reliable pressure control protection for industrial production processes.

[0121] It should be understood that the size of the serial number of each step does not mean the order of execution, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0122] Corresponding to the control method described in the above embodiments, the present embodiment also provides a pilot valve device, each module of which can implement each step of the control method.

[0123] Please refer to Figure 2 The present application proposes a pilot valve device comprising a mechanical execution unit, a data detection unit 80 and a control processing unit 90.

[0124] The mechanical execution unit comprises a valve body 10, a pressure regulating assembly, a spring assembly and a sealing assembly 50. The inner cavity of the valve body 10 is provided with a piston accommodating cavity 11 and a modulation cavity 12 which are communicated through a piston shaft hole 13. The pressure regulating assembly comprises a piston 20 slidingly arranged in the piston accommodating cavity 11, a pressure stabilizing cavity assembly 30 arranged in the modulation cavity 12 and an axially movable piston shaft 40, one end of which is connected to the piston 20 and the other end extends into the pressure stabilizing cavity. The spring assembly comprises a spring 60 and a pressure regulating component 70, the spring 60 being clamped between the piston 20 and the pressure regulating component 70, and the pressure regulating component 70 being used to adjust the spring pre-tightening force. The sealing assembly 50 is installed at the bottom of the piston accommodating cavity 11 and is provided with a through hole through which the piston shaft 40 passes. The data detection unit 80 comprises a pressure sensor 81 arranged in the piston accommodating cavity 11 and a displacement sensor 82 arranged in the pressure stabilizing cavity. The control processing unit 90 is signal connected with the data detection unit 80 and the pressure regulating component 70, comprising a memory for storing data and a processor for executing control programs.

[0125] Specifically, the pressure sensor 81 detects the medium pressure in the valve body 10 in real time, the displacement sensor 82 detects the displacement of the piston shaft 40, and the control processing unit 90 maps the real-time pressure to the target displacement, calculates the displacement deviation, and generates the adjustment instruction. The pressure regulating component 70 receives the instruction to adjust the spring compression amount, changes the axial position of the piston shaft 40, and then adjusts the cross-sectional area of the medium flow passage 44 through the gap change between the intercepting section 41 and the through hole. When the piston shaft 40 moves to the safe position, the largest diameter part of the intercepting section 41 is sealed with the through hole to block the medium flow; in the working position, the cross-sectional area of the annular flow gap is dynamically adjusted according to the displacement of the piston shaft 40, forming a closed-loop control of pressure and displacement. The structure integrates mechanical execution, data detection, and control processing unit 90, realizes real-time calibration of spring pre-tightening force and self-adaptive adjustment of medium pressure, and avoids adjustment lag and safety hazards caused by manual intervention.

[0126] As a preferred embodiment, the scheme of the application is implemented as follows:

[0127] The pilot valve device includes a mechanical execution unit, a data detection unit 80, and a control processing unit 90. The mechanical execution unit includes a valve body 10, a pressure regulating assembly, a spring assembly, and a sealing assembly 50.

[0128] Please refer to Figure 2 and Figure 3 , the inner cavity of the valve body 10 is provided with a piston containing cavity 11 and a modulation cavity 12 which are in communication through a piston shaft hole 13. The outer wall of the valve body is also provided with a medium inlet 14, a medium outlet 16, and a pressure relief port 17, wherein the medium inlet is in communication with the piston containing cavity 11, the medium outlet 16 is in communication with the piston shaft hole 13, and the pressure relief port is in communication with the modulation cavity 12; the pressure regulating assembly is used to adjust the medium pressure in the valve body 10, and includes a piston 20 slidingly arranged in the piston containing cavity 11, a pressure stabilizing cavity assembly 30 arranged in the modulation cavity 12, and a piston shaft 40 axially movably arranged in the inner cavity of the valve body 10. One end of the piston shaft 40 is connected to the piston 20, and the other end extends into a pressure stabilizing cavity 321 in the pressure stabilizing cavity assembly 30.

[0129] The spring assembly includes a spring 60 and a pressure regulating component 70. The spring 60 is clamped between the piston 20 and the pressure regulating component 70, and is used to provide a pre-tightening force for the piston 20; the pressure regulating component 70 is used to adjust the spring pre-tightening force. The sealing assembly 50 is installed at the bottom of the piston containing cavity 11, and is provided with a through hole through which the piston shaft 40 passes.

[0130] The data detection unit 80 includes a pressure sensor 81 and a displacement sensor 82. The pressure sensor 81 is arranged at the piston containing cavity 11 to obtain the real-time medium pressure in the valve body 10, and the displacement sensor 82 is arranged at the corresponding end position of the piston shaft 40 in the pressure stabilizing cavity of the pressure stabilizing cavity assembly 30 to detect the real-time displacement of the piston shaft 40.

[0131] The control processing unit 90 is in signal connection with the data detection unit 80 and the pressure regulating component 70, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the following method is implemented:

[0132] The real-time medium pressure of the valve body 10 is obtained in real time by the pressure sensor 81; the real-time displacement amount of the piston shaft 40 is obtained in real time by the displacement sensor 82; the target displacement amount of the piston shaft 40 is determined based on the real-time medium pressure; the displacement deviation data is determined based on the real-time displacement amount and the target displacement amount; when it is determined that the pressure regulating component 70 needs to be adjusted according to the displacement deviation data, the adjustment data is determined based on the displacement deviation data; and the pre-tightening force of the spring 60 is adjusted by the pressure regulating component 70 based on the adjustment data.

[0133] Through the above technical solution, the application realizes the automatic adjustment of the pilot valve device. Since the pressure sensor 81 and the displacement sensor 82 are used to monitor the medium pressure in the valve body 10 and the displacement of the piston shaft 40 in real time, and the control processing unit 90 analyzes the data and generates adjustment instructions, the pre-tightening force of the spring is automatically controlled by the pressure regulating component 70, avoiding the inconvenience and risk of manual intervention. This control method can timely respond to changes in system pressure, maintain the stability of the position of the piston shaft 40, and improve the pressure regulating precision and reliability of the pilot valve. At the same time, the automatic adjustment mechanism reduces the need for downtime maintenance, improving the operating efficiency of the equipment. In addition, real-time data monitoring and automatic adjustment functions enhance the safety of the system, enabling quick response to abnormal situations and reducing the risk of overpressure or leakage.

[0134] Further, the application proposes that the pressure regulating component 70 includes an adjusting bolt 72 and a micro stepping motor 71, and the micro stepping motor 71 drives the adjusting bolt 72 to rotate through a transmission mechanism to change the compression amount of the spring 60.

[0135] It can be understood that the micro stepping motor 71 and the adjusting bolt 72 can be connected through a transmission mechanism, and the rotational motion of the stepping motor 71 is converted into the axial displacement of the adjusting bolt 72 through the transmission mechanism. The threads of the adjusting bolt 72 are matched with the valve cover threaded hole, and the end thereof abuts against the spring 60, and when the adjusting bolt 72 is screwed in or out, the compression amount of the spring 60 changes accordingly.

[0136] Specifically, when the control processing unit 90 outputs a pulse signal to drive the micro stepping motor 71, the rotational movement of the motor is transmitted to the adjusting bolt 72 through the transmission mechanism. The rotation of the adjusting bolt 72 causes it to move axially, pushing the end of the spring 60 to produce displacement, thereby changing the pre-tightening force of the spring 60. When the displacement deviation data is detected to require adjustment, the processor calculates the required number of pulses according to the adjustment amplitude, drives the stepping motor 71 to rotate by a corresponding angle, and moves the adjusting bolt 72 to the target position. For example, by using a fine thread with a lead of 1 mm, combined with a stepping motor 71 with 200 steps per revolution, an axial displacement accuracy of 5 μm per step can be achieved. This axial displacement directly changes the distance between the spring 60 seat and the piston 20, causing the spring compression amount to change correspondingly, thereby accurately adjusting the pre-tightening force.

[0137] Through the above technical solution, the application converts rotational movement into linear displacement through mechanical transmission, achieving accurate control of spring compression amount and avoiding errors and risks caused by manual operation. At the same time, the high resolution of the micro stepping motor 71 and the speed reduction design of the transmission mechanism make the adjustment accuracy of the spring pre-tightening force reach the micron level, ensuring the stability of pressure control.

[0138] Further, as shown in Figure 4 the piston shaft 40 comprises a cutoff section 41 and a flow-through section 42, the piston shaft 40 passes through the piston shaft hole 13, and the outer diameter of each part thereof is smaller than the hole diameter of the piston shaft hole 13 to form a medium flow-through channel 44; the cutoff section 41 has a variable diameter structure that cooperates with the through hole of the sealing assembly 50, and is used to adjust the cross-sectional area of the medium flow-through channel 44 by changing the axial movement of the piston shaft 40, forming an adjustable medium flow-through channel 44; when the piston shaft 40 is in the safe position, the largest diameter part of the cutoff section 41 is in sealing cooperation with the through hole to block the medium flow-through; when the piston shaft 40 is in the working position, an annular flow-through gap is formed between the cutoff section 41 and the through hole, and the cross-sectional area of the annular flow-through gap changes with the displacement of the piston shaft 40.

[0139] Among them, the variable diameter structure of the cutoff section 41 adopts a conical or stepped design, and its diameter gradually changes along the axial direction; the outer diameter of the flow-through section 42 remains constant, and the gap between it and the piston shaft hole 13 forms a fixed flow-through cross section. The cutoff section 41 and the through hole of the sealing assembly 50 are cooperated with hard sealing or elastic sealing materials to ensure complete blocking in the safe position. When the piston shaft 40 moves, the relative position of the variable diameter part of the cutoff section 41 and the through hole changes, so that the width and the axial coverage length of the annular flow-through gap change synchronously, realizing the continuous adjustment of the cross-sectional area.

[0140] Specifically, when the piston shaft 40 is controlled to move to the safe position, the maximum diameter part of the intercepting section 41 gradually embeds into the through hole until the complete sealing contact, at which time the medium flow passage 44 is completely blocked, and the system enters the safe state. In the working position, an annular gap is formed between the intercepting section 41 of the piston shaft 40 and the through hole, and the flow rate of the medium passing through the gap is determined by the gap width and the axial coverage length together. With the change of the displacement amount of the piston shaft 40, the relative position of the variable diameter part of the intercepting section 41 and the through hole changes linearly or nonlinearly, and the equivalent cross-sectional area of the annular gap adjusts accordingly, thereby accurately controlling the medium flow rate. For example, when the piston shaft 40 moves 1 mm towards the pressure regulating component 70, the tapered surface of the intercepting section 41 causes the annular gap width to increase by 0.2 mm and the axial coverage length to decrease by 2 mm, and under the combined action, the flow passage cross-sectional area expands to 1.5 times the original value. The structure directly links the displacement amount and the cross-sectional area, realizes linear regulation of the medium pressure, and at the same time avoids the pressure impact caused by the stepwise opening and closing of the traditional valve.

[0141] As a preferred embodiment, please refer to Figure 4 , the present application is implemented as follows: the piston shaft 40 is alternately composed of the intercepting section 41 and the flow passage section 42, the outer surface of the intercepting section 41 is in a stepped variable diameter structure, specifically the intercepting section 41 includes a thin shaft section 411 and a thick shaft section 412, which are connected by a tapered surface 423, and the outer diameter of the flow passage section 42 is uniform and smaller than the hole diameter of the piston shaft hole 13. When the piston shaft 40 is in the safe position, the thick shaft section 412 of the intercepting section 41 forms an interference fit with the elastic sealing ring on the inner wall of the through hole of the sealing assembly 50, achieving sealing; when the piston shaft 40 moves axially to the working position, the stepped variable diameter section of the intercepting section 41 forms an annular gap with the inner wall of the through hole, and the medium is transmitted through the composite flow channel composed of the flow passage section 42, the gap between the shaft hole and the annular gap. The displacement amount of the piston shaft 40 is monitored in real time by the displacement sensor 82, and when an abnormal pressure is detected, the control processing unit 90 drives the pressure regulating component 70 to reset the piston shaft 40 to the safe position, at which time the maximum diameter section of the intercepting section 41 completely fits the through hole, achieving rapid blocking of the medium flow passage 44. Through the above technical solution, the present application can realize automatic opening and closing control of the medium flow passage according to the system pressure state, and realize physical blocking of the flow channel through accurate control of the axial displacement of the piston shaft in emergency working conditions, avoiding the risk of medium leakage caused by spring failure or actuator delay of traditional valves. The stepped variable diameter structure and the sealing assembly are designed in cooperation, which not only ensures the linearity of flow regulation in normal working state, but also forms a double sealing structure in the safe position, effectively improving the blocking reliability of high-pressure medium.

[0142] The above merely provides an example of the present application, and is not used to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A pilot valve control method for automatic pressure regulation based on data detection, characterized by, The pilot valve includes a valve body, a pressure regulating assembly, a spring assembly, a pressure sensor, and a displacement sensor; the pressure regulating assembly includes a piston and a piston shaft; the spring assembly includes a spring acting on the piston and a pressure regulating component for adjusting the spring preload; the pressure sensor is used to acquire the real-time medium pressure inside the valve body, and the displacement sensor is used to detect the real-time displacement of the piston shaft; the method includes: The real-time medium pressure of the valve body is obtained through the pressure sensor. The displacement sensor is used to obtain the real-time displacement of the piston shaft. Determining the target displacement of the piston shaft based on the real-time medium pressure includes: querying the stored pressure-displacement correlation curve, and using the piston shaft displacement corresponding to the real-time medium pressure as the target displacement; wherein the pressure-displacement correlation curve is determined by experimental calibration or theoretical calculation and is used to characterize the correspondence between pressure and piston shaft equilibrium position. Determining displacement deviation data based on the real-time displacement and the target displacement includes: obtaining a displacement deviation value based on the difference between the real-time displacement and the target displacement; and performing low-pass filtering on the displacement deviation value to obtain the displacement deviation data. If it is determined from the displacement deviation data that the pressure regulating component needs adjustment, the adjustment data is determined based on the displacement deviation data; Controlling the pressure regulating component to adjust the preload of the spring based on the adjustment data includes: generating a control signal with pulse width based on the adjustment data to drive the pressure regulating component.

2. The control method according to claim 1, characterized by, When it is determined that the voltage regulating component needs to be adjusted based on the displacement deviation data, the adjustment data is determined based on the displacement deviation data, including: determining whether the absolute value of the displacement deviation data is greater than a set adjustment threshold; if it is greater than the adjustment threshold, then determining the adjustment direction based on the sign of the displacement deviation data, and determining the adjustment range based on the magnitude of the absolute value of the displacement deviation data.

3. The control method according to claim 1, characterized by, The method further includes: comparing the collected real-time medium pressure and real-time displacement with the set threshold range of the pressure-displacement correlation curve; if the detection data deviates from the threshold range for more than a set time or number of times, an alarm signal is triggered, and the pressure regulating component is controlled to drive the piston shaft to move to a safe position.

4. A pilot valve device characterized by comprising: It includes a mechanical actuation unit, a data detection unit, and a control processing unit; the mechanical actuation unit comprises: The valve body has an inner cavity provided with a piston receiving cavity and a modulation cavity that are interconnected through a piston shaft hole; The pressure regulating assembly, used to regulate the pressure of the medium within the valve body, includes: a piston slidably disposed within the piston receiving cavity, a pressure stabilizing cavity assembly disposed within the modulation cavity, and a piston shaft axially movable within the valve body cavity; one end of the piston shaft is connected to the piston, and the other end extends into the pressure stabilizing cavity within the pressure stabilizing cavity assembly; the piston shaft has a safe position; and The spring assembly includes the spring and the pressure adjusting component; the spring is sandwiched between the piston and the pressure adjusting component and is used to provide a preload force to the piston; the pressure adjusting component is used to adjust the spring preload force. A sealing assembly is arranged at the bottom of the piston accommodating cavity and has a through hole through which the piston shaft passes; The data detection unit comprises the pressure sensor and the displacement sensor, the pressure sensor is arranged at the piston accommodating cavity to obtain the real-time medium pressure in the valve body, and the displacement sensor is arranged at the corresponding end position of the piston shaft in the pressure stabilizing cavity of the pressure stabilizing cavity assembly to detect the real-time displacement of the piston shaft; The control processing unit is in signal connection with the data detection unit and the pressure regulating component, comprises a memory, a processor and a computer program stored in the memory and executable on the processor, and the processor implements the method according to any one of claims 1 to 3 when executing the computer program.

5. The pilot valve apparatus according to claim 4, characterized by The pressure regulating component comprises an adjusting bolt and a micro stepping motor, the micro stepping motor drives the adjusting bolt to rotate through a transmission mechanism to change the compression amount of the spring.

6. The pilot valve apparatus according to claim 4, characterized by The piston shaft comprises a flow blocking section and a flow passing section, passes through the piston shaft hole; the outer diameter of the piston shaft at each position is smaller than the hole diameter of the piston shaft hole to form a medium flow passing channel; and the flow blocking section has a variable diameter structure matched with the through hole of the sealing assembly, used for adjusting the sectional area of the medium flow passing channel through the change of the axial movement of the piston shaft to form an adjustable medium flow passing channel; when the piston shaft is located at the safety position, the largest diameter part of the flow blocking section is in sealing cooperation with the through hole to block the medium flow; when the piston shaft is located at the working position, an annular flow passing gap is formed between the flow blocking section and the through hole, and the sectional area of the annular flow passing gap changes with the displacement of the piston shaft.

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