Intelligent pneumatic electromagnetic switch valve with valve position feedback and control method

Abstract

The invention discloses an intelligent pneumatic electromagnetic switch valve with a valve position feedback function and a control method. The intelligent pneumatic electromagnetic switch valve comprises a valve body and valve element assembly, an electromagnetic driving assembly, a power driving and detecting circuit, a valve position detecting assembly and a microprocessor control unit. The valve body and the valve core assembly are used for enabling the valve core and the channel structure to form a gas path switching unit; the electromagnetic driving assembly is used for driving the valve element to be opened and closed. The power driving and detecting circuit is used for driving the electromagnetic coil and collecting coil voltage and current and valve element valve position signals in real time. The valve position detection assembly is used for obtaining a valve position signal of the valve element. The microprocessor control unit is used for resolving the position of a valve element in real time and conducting sectional type PWM control decision making according to the real-time valve position, coil current and the instruction switch state. Executing a light-weight position adjustment algorithm according to the valve position error to calculate a driving coil current; real-time continuous detection of the position of the valve element is achieved, the driving current is automatically adjusted, and the electromagnetic valve has the intelligent, self-adaptive and high-reliability action capacity.

Description

Technical Field

[0001] This invention relates to the field of pneumatic control technology, and more specifically to an intelligent pneumatic solenoid switch valve with valve position feedback and a control method thereof. Background Technology

[0002] Pneumatic solenoid valves, as important actuators in industrial automation systems, are widely used in process control, equipment manufacturing, environmental engineering, and intelligent agricultural machinery.

[0003] Most existing pneumatic solenoid valves use an on / off drive method, where the valve core position is determined solely by the balance between the electromagnet's attraction and the spring force. This lack of real-time position detection capability makes precise opening adjustment and operational status monitoring difficult. Due to the absence of valve position feedback, traditional solenoid valves generally suffer from the following drawbacks: Firstly, the valve core's operation is unobservable, making it impossible to accurately determine whether the valve is fully open or closed. This results in the control system only being able to execute coarse time-based logical actions, which cannot adapt to complex operating conditions. Secondly, the valve core is affected by factors such as air pressure disturbance, wear and magnetic circuit aging, and its motion characteristics drift with the use time. The existing structure cannot automatically calibrate or compensate for this, which easily leads to problems such as lag, jamming or unstable operation. Third, traditional structures cannot provide continuous information on valve core stroke, thus they cannot be combined with intelligent control algorithms, digital twins, or adaptive drive strategies, making it difficult to meet the needs of intelligent equipment for high-precision and high-reliability actuators.

[0004] In addition, in current research, some sensor-integrated solenoid valves attempt to obtain the valve core position using photoelectric, piezoresistive, and eddy current methods, but these methods have limitations such as increased structural volume, weak anti-contamination ability, high cost, or inability to be integrated into small valve bodies. Furthermore, in open literature and published patents, most solutions only achieve single-point switch state recognition and have not formed a highly robust valve position detection solution that can continuously track the movement of the valve core.

[0005] Therefore, what those skilled in the art urgently need to solve is how to address the problems of existing pneumatic solenoid switching valves, such as lack of valve position feedback, unobservable action, low control accuracy, and inability to be used in conjunction with intelligent algorithms. Summary of the Invention

[0006] In view of the above problems, the present invention provides an intelligent pneumatic solenoid switch valve with valve position feedback and a control method to overcome or at least partially solve the above problems.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: An intelligent pneumatic solenoid switching valve with valve position feedback includes: a valve body and valve core assembly, an electromagnetic drive assembly, a power drive and detection circuit, a valve position detection assembly, and a microprocessor control unit; The valve body and valve core assembly is used to form an air circuit switching unit between the valve core and the channel structure, so that the valve core moves under the combined action of electromagnetic force, return spring force and pneumatic force. Electromagnetic drive assembly, used to drive the opening and closing action of the valve core; The power drive and detection circuit is used to apply drive current to the electromagnetic drive component based on the drive control signal, and simultaneously acquire the current signal and the valve position signal output by the valve position detection component. The valve position detection component is used to collect changes in the magnetic field and output a valve position signal related to the valve core position. The microprocessor control unit is used to parse the switch control command to obtain the corresponding target valve position and generate the drive control signal; calculate the valve position signal and, based on the relationship between the current position of the valve core and the target valve position, execute a segmented PWM control strategy to dynamically adjust the PWM duty cycle of the electromagnetic coil; calculate the valve position error based on the continuously acquired real-time position signal of the valve core and execute a lightweight position adjustment algorithm to calculate the control current driving the electromagnetic drive component.

[0008] Preferably, the intelligent pneumatic solenoid switch valve with valve position feedback further includes a host computer / PLC communication interface for interacting with external automation systems via RS485, CAN, or IO-Link.

[0009] Preferably, the electromagnetic drive assembly includes an electromagnetic coil, an iron core, an armature, and a return spring; the power drive and detection circuit applies a drive current to the electromagnetic coil, causing the valve core to start moving under the combined action of electromagnetic force, return spring force, and pneumatic force.

[0010] Preferably, the valve position detection component includes a magnetic displacement indicator, an annular magnetic grating, and a sensor array. The sensor array is arranged in an annular detection groove on the outer periphery of the valve body. The sensor array is any one of a multi-point Hall sensor array, an eddy current displacement probe, or a magnetoresistive sensor. The magnetic displacement indicator is located on the valve core, and the sensor array is arranged coaxially with the magnetic displacement indicator. When the valve core moves, the magnetic valve position indicator moves with the valve core and causes a change in the magnetic field distribution. The sensor array collects the changes in the magnetic field and outputs a valve position signal related to the position of the valve core.

[0011] Preferably, the method for the microprocessor control unit to calculate the valve core position in real time is to obtain the valve core position through least squares estimation:

[0012] in, The desired valve core position is... This represents the solution for the variable star that minimizes the sum of squared residuals between the sensor-measured voltage and the voltage predicted by the magnetic field model. , For the number of sensors, Let be the output voltage of the i-th Hall sensor at time t. , For calibration coefficients, This is a magnetic field model.

[0013] The preferred calibration model for a multi-point Hall array is as follows:

[0014] in, For valve core in position The corresponding magnetic flux density at that time These are the zero-point coefficients obtained through calibration. This is the zero-bias compensation value for the sensor; the change in magnetic field with displacement is mapped into a directly measurable voltage signal through the calibration model relationship.

[0015] Preferably, the segmented PWM control decision includes: Rapid engagement phase: High duty cycle PWM provides a large current, enabling the valve core to move rapidly against the spring force and air source back pressure; Holding phase: The duty cycle is dynamically adjusted using valve position feedback to keep the valve core stable in the target position or in a fully open state.

[0016] Preferably, the method for calculating the control current of the drive electromagnetic drive component based on the valve position error using a lightweight position adjustment algorithm is as follows:

[0017] in, The control current for driving the electromagnetic coil, This is a proportionality coefficient, used to provide corresponding driving force adjustments based on the magnitude of the error; These are differential coefficients, used to suppress vibration and overshoot based on the trend of error changes; This represents the valve position error at the current moment. The rate of change of error;

[0018] in, The desired position that the executing agency needs to achieve, including fully open, fully closed, or any intermediate position; This refers to the actual position of the valve core obtained through real-time detection.

[0019] A control method for an intelligent pneumatic solenoid valve with valve position feedback, based on the aforementioned intelligent pneumatic solenoid valve with valve position feedback, includes the following steps: S1. The microprocessor control unit (MCU) receives the switch control command issued by the host computer and parses the command to obtain the corresponding target valve position. The target valve position includes the fully open position, fully closed position, or preset intermediate stroke position of the valve core. S2.MCU generates a drive control signal based on the target valve position, and applies a drive current to the solenoid coil through the power drive and detection circuit, so that the valve core starts to move under the combined action of electromagnetic force, return spring force and pneumatic force; S3. During the movement of the valve core, the power drive and detection circuit synchronously acquires the real-time position signal of the valve core output by the valve position detection component and the current signal of the electromagnetic coil, and sends the signal to the MCU. The MCU executes a segmented PWM control strategy according to the relationship between the current position of the valve core and the target valve position, and dynamically adjusts the PWM duty cycle of the electromagnetic coil to control the movement speed and movement process of the valve core. S4.MCU calculates the valve position error based on the continuously acquired real-time valve core position signal, and executes a lightweight position adjustment algorithm based on the valve position error to calculate the control current of the drive solenoid coil, so that the valve core gradually approaches the target valve position. When the valve position error meets the preset threshold or the valve core position remains stable within a preset time, the valve action is determined to be completed, and the valve core stroke confirmation and operation status monitoring are completed at the same time.

[0020] Preferably, the control method for an intelligent pneumatic solenoid valve with valve position feedback further includes: S5. The MCU feeds back the final action state, valve position information and operating status of the valve to the host computer to realize remote monitoring and management of the valve status.

[0021] As can be seen from the above technical solution, compared with the prior art, the present invention discloses an intelligent pneumatic solenoid switching valve with valve position feedback and a control method, which has the following beneficial effects: By combining the magnetic field information obtained by the multi-point Hall array with the least squares solution model, continuous displacement detection of the valve core throughout its entire stroke can be achieved without changing the original valve body size. This overcomes the problem of unobservable operation of traditional solenoid valves and improves the reliability and diagnosability of the operation. By utilizing the PD control law driven by valve position error, the drive current can be dynamically adjusted according to the actual valve core position, thereby compensating for the action deviation caused by factors such as air pressure disturbance, magnetic circuit aging and mechanical wear, and significantly improving the valve's repeatability and response consistency. The sensing unit, calculation model and control strategy of the present invention are highly integrated inside the valve body, eliminating the need for an external position detection device. Therefore, it has the advantages of compact structure, strong anti-pollution ability and simple installation and maintenance, and can work stably in high dust, high humidity and vibration environments. The valve position continuous information provided by this invention can directly interact with host computer controllers, intelligent diagnostic systems, digital twin platforms, etc., enabling pneumatic solenoid valves to be expanded from traditional on / off actuators into intelligent execution units that can participate in high-precision control and status monitoring. This improves the overall automation level and controllability of equipment, and provides higher application value for intelligent manufacturing and equipment operation under complex working conditions. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of an intelligent pneumatic solenoid switch valve with valve position feedback provided in an embodiment of the present invention; Figure 2 This is a flowchart of a smart pneumatic solenoid valve control method with valve position feedback provided in an embodiment of the present invention. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] This invention discloses an intelligent pneumatic electromagnetic switching valve with valve position feedback, comprising: a valve body and valve core assembly, an electromagnetic drive assembly, a power drive and detection circuit, a valve position detection assembly, and a microprocessor control unit; The valve body and valve core assembly is used to form an air circuit switching unit between the valve core and the channel structure, so that the valve core moves under the combined action of electromagnetic force, return spring force and pneumatic force. Electromagnetic drive assembly, used to drive the opening and closing action of the valve core; The power drive and detection circuit is used to apply drive current to the electromagnetic drive component based on the drive control signal, and simultaneously acquire the current signal and the valve position signal output by the valve position detection component. The valve position detection component is used to collect changes in the magnetic field and output a valve position signal related to the valve core position. The microprocessor control unit is used to parse the switch control command to obtain the corresponding target valve position and generate the drive control signal; calculate the valve position signal and, based on the relationship between the current position of the valve core and the target valve position, execute a segmented PWM control strategy to dynamically adjust the PWM duty cycle of the electromagnetic coil; calculate the valve position error based on the continuously acquired real-time position signal of the valve core and execute a lightweight position adjustment algorithm to calculate the control current driving the electromagnetic drive component.

[0026] To further implement the above technical solution, an intelligent pneumatic solenoid switching valve with valve position feedback also includes a host computer / PLC communication interface for interacting with external automation systems via RS485, CAN, or IO-Link.

[0027] To further implement the above technical solution, the electromagnetic drive assembly includes an electromagnetic coil, an iron core, an armature, and a return spring; the power drive and detection circuit applies a drive current to the electromagnetic coil, causing the valve core to start moving under the combined action of electromagnetic force, return spring force, and pneumatic force.

[0028] To further implement the above technical solution, the valve position detection component includes a magnetic displacement indicator, an annular magnetic grating, and a sensor array. The sensor array is arranged in an annular detection groove on the outer periphery of the valve body. The sensor array can be any one of a multi-point Hall sensor array, an eddy current displacement probe, or a magnetoresistive sensor. The magnetic displacement indicator is located on the valve core, and the sensor array is arranged coaxially with the magnetic displacement indicator. When the valve core moves, the magnetic valve position indicator moves with the valve core and causes a change in the magnetic field distribution. The sensor array collects the changes in the magnetic field and outputs a valve position signal related to the position of the valve core.

[0029] In this embodiment, a radially magnetized miniature permanent magnet is disposed on the valve core. When the valve core moves under the action of aerodynamic and electromagnetic forces, the magnetic field generated by the permanent magnet changes with the position. A sensor array is arranged in an annular detection groove on the outside of the valve body to measure the magnetic field strength. The change allows for adjustment of the core alignment position. Real-time inversion.

[0030] To further implement the above technical solution, the microprocessor control unit calculates the valve core position in real time by obtaining the valve core position through least squares estimation:

[0031] in, The desired valve core position is... This indicates that solving for the voltage measured by the sensor is required. Voltage prediction with magnetic field model The autovariable with the smallest sum of squared residuals , This represents the output voltage value predicted by the i-th sensor based on the calibration model when the valve core is at position x. For the number of sensors, Let be the output voltage of the i-th Hall sensor at time t. , For calibration coefficients, This is a magnetic field model.

[0032] The valve position signal is obtained after real-time calculation by the MCU, which can realize displacement detection with an accuracy of 0.02-0.05mm, solving the technical problem that traditional electromagnetic switches cannot monitor the valve position.

[0033] To further implement the above technical solution, the calibration model for the multi-point Hall array is as follows:

[0034] in, For valve core in position The corresponding magnetic flux density at that time These are the zero-point coefficients obtained through calibration. This is the zero-bias compensation value for the sensor; the change in magnetic field with displacement is mapped into a directly measurable voltage signal through the calibration model relationship.

[0035] In this embodiment, to achieve rapid opening and precise positioning, the electromagnetic force model is represented as follows:

[0036] in, For a moment The electromagnetic force exerted by an electromagnet on an armature. This is the equivalent inductance of the air gap as the valve core position changes. This represents the rate of change of inductance with displacement. The coil current; This model demonstrates the relationship between electromagnetic force and total circuit change and the square of current, providing a theoretical basis for dynamic control of valve action and current regulation strategies.

[0037] To further implement the above technical solution, the segmented PWM control decision includes: Rapid engagement phase: High duty cycle PWM provides a large current, enabling the valve core to move rapidly against the spring force and air source back pressure; Holding phase: The duty cycle is dynamically adjusted using valve position feedback to keep the valve core stable in the target position or in a fully open state.

[0038] To further implement the above technical solution, the method for calculating the control current of the drive electromagnetic drive component based on the valve position error using a lightweight position adjustment algorithm is as follows:

[0039] in, The control current for driving the electromagnetic coil, This is a proportionality coefficient, used to provide corresponding driving force adjustments based on the magnitude of the error; These are differential coefficients, used to suppress vibration and overshoot based on the trend of error changes; This represents the valve position error at the current moment. The rate of change of error;

[0040] in, The desired position that the executing agency needs to achieve, including fully open, fully closed, or any intermediate position; This refers to the actual position of the valve core obtained through real-time detection.

[0041] In practical applications, detection Immediately shut down the driver; when If there is no change within a preset time, an alarm will be triggered.

[0042] A control method for an intelligent pneumatic solenoid valve with valve position feedback, based on an intelligent pneumatic solenoid valve with valve position feedback, such as... Figure 2 This includes the following steps: S1. The microprocessor control unit (MCU) receives the switch control command issued by the host computer and parses the command to obtain the corresponding target valve position. The target valve position includes the fully open position, fully closed position, or preset intermediate stroke position of the valve core. S2.MCU generates a drive control signal based on the target valve position, and applies a drive current to the solenoid coil through the power drive and detection circuit, so that the valve core starts to move under the combined action of electromagnetic force, return spring force and pneumatic force; S3. During the movement of the valve core, the power drive and detection circuit synchronously acquires the real-time position signal of the valve core output by the valve position detection component and the current signal of the electromagnetic coil, and sends the signal to the MCU. The MCU executes a segmented PWM control strategy according to the relationship between the current position of the valve core and the target valve position, and dynamically adjusts the PWM duty cycle of the electromagnetic coil to control the movement speed and movement process of the valve core. S4.MCU calculates the valve position error based on the continuously acquired real-time valve core position signal, and executes a lightweight position adjustment algorithm based on the valve position error to calculate the control current of the drive solenoid coil, so that the valve core gradually approaches the target valve position. When the valve position error meets the preset threshold or the valve core position remains stable within a preset time, the valve action is determined to be completed, and the valve core stroke confirmation and operation status monitoring are completed at the same time.

[0043] To further implement the above technical solution, a control method for an intelligent pneumatic solenoid valve with valve position feedback also includes: S5. The MCU feeds back the valve's final action state, valve position information, and operating status to the host computer to realize remote monitoring and management of the valve status.

[0044] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0045] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An intelligent pneumatic solenoid switching valve with valve position feedback, characterized in that, include: Valve body and valve core assembly, electromagnetic drive assembly, power drive and detection circuit, valve position detection assembly and microprocessor control unit; The valve body and valve core assembly is used to form an air circuit switching unit between the valve core and the channel structure, so that the valve core moves under the combined action of electromagnetic force, return spring force and pneumatic force. Electromagnetic drive assembly, used to drive the opening and closing action of the valve core; The power drive and detection circuit is used to apply drive current to the electromagnetic drive component based on the drive control signal, and simultaneously acquire the current signal and the valve position signal output by the valve position detection component. The valve position detection component is used to collect changes in the magnetic field and output a valve position signal related to the valve core position. The microprocessor control unit is used to parse the switch control command to obtain the corresponding target valve position and generate the drive control signal; calculate the valve position signal and, based on the relationship between the current position of the valve core and the target valve position, execute a segmented PWM control strategy to dynamically adjust the PWM duty cycle of the electromagnetic coil; calculate the valve position error based on the continuously acquired real-time position signal of the valve core and execute a lightweight position adjustment algorithm to calculate the control current driving the electromagnetic drive component.

2. The intelligent pneumatic solenoid switching valve with valve position feedback as described in claim 1, characterized in that, It also includes a host computer / PLC communication interface for interacting with external automation systems via RS485, CAN, or IO-Link.

3. The intelligent pneumatic solenoid switching valve with valve position feedback as described in claim 1, characterized in that, The electromagnetic drive assembly includes an electromagnetic coil, an iron core, an armature, and a return spring; the power drive and detection circuit applies a drive current to the electromagnetic coil, causing the valve core to start moving under the combined action of electromagnetic force, return spring force, and pneumatic force.

4. The intelligent pneumatic solenoid switching valve with valve position feedback as described in claim 1, characterized in that, The valve position detection assembly includes a magnetic displacement indicator, an annular magnetic grid, and a sensor array. The sensor array is arranged in an annular detection groove on the outer periphery of the valve body. The sensor array can be any one of a multi-point Hall sensor array, an eddy current displacement probe, or a magnetoresistive sensor. The magnetic displacement indicator is located on the valve core, and the sensor array is arranged coaxially with the magnetic displacement indicator. When the valve core moves, the magnetic valve position indicator moves with the valve core and causes a change in the magnetic field distribution. The sensor array collects the changes in the magnetic field and outputs a valve position signal related to the valve core position.

5. The intelligent pneumatic solenoid switching valve with valve position feedback as described in claim 1, characterized in that, The microprocessor control unit calculates the valve core position in real time by using least squares estimation. in, The desired valve core position is... This represents the solution for the variable star that minimizes the sum of squared residuals between the sensor-measured voltage and the voltage predicted by the magnetic field model. , For the number of sensors, Let be the output voltage of the i-th Hall sensor at time t. , For calibration coefficients, This is a magnetic field model.

6. The intelligent pneumatic solenoid switching valve with valve position feedback as described in claim 5, characterized in that, The calibration model for a multi-point Hall array is as follows: in, For valve core in position The corresponding magnetic flux density at that time These are the zero-point coefficients obtained through calibration. This is the zero-bias compensation value for the sensor; the change in magnetic field with displacement is mapped into a directly measurable voltage signal through the calibration model relationship.

7. The intelligent pneumatic solenoid switching valve with valve position feedback as described in claim 1, characterized in that, Segmented PWM control decisions include: Rapid engagement phase: High duty cycle PWM provides a large current, enabling the valve core to move rapidly against the spring force and air source back pressure; Holding phase: The duty cycle is dynamically adjusted using valve position feedback to keep the valve core stable in the target position or in a fully open state.

8. The intelligent pneumatic solenoid switching valve with valve position feedback as described in claim 1, characterized in that, The method for calculating the control current of the electromagnetic drive component based on the valve position error using a lightweight position adjustment algorithm is as follows: in, The control current for driving the electromagnetic coil, This is a proportionality coefficient, used to provide corresponding driving force adjustments based on the magnitude of the error; These are differential coefficients, used to suppress vibration and overshoot based on the trend of error changes; This represents the valve position error at the current moment. The rate of change of error; in, The desired position that the executing agency needs to achieve, including fully open, fully closed, or any intermediate position; This refers to the actual position of the valve core obtained through real-time detection.

9. A control method for an intelligent pneumatic solenoid switch valve with valve position feedback, characterized in that, A smart pneumatic solenoid switching valve with valve position feedback according to any one of claims 1-8 includes the following steps: S1. The microprocessor control unit (MCU) receives the switch control command issued by the host computer and parses the command to obtain the corresponding target valve position. The target valve position includes the fully open position, fully closed position, or preset intermediate stroke position of the valve core. S2.MCU generates a drive control signal based on the target valve position, and applies a drive current to the solenoid coil through the power drive and detection circuit, so that the valve core starts to move under the combined action of electromagnetic force, return spring force and pneumatic force; S3. During the movement of the valve core, the power drive and detection circuit synchronously acquires the real-time position signal of the valve core output by the valve position detection component and the current signal of the electromagnetic coil, and sends the signal to the MCU. The MCU executes a segmented PWM control strategy according to the relationship between the current position of the valve core and the target valve position, and dynamically adjusts the PWM duty cycle of the electromagnetic coil to control the movement speed and movement process of the valve core. S4.MCU calculates the valve position error based on the continuously acquired real-time valve core position signal, and executes a lightweight position adjustment algorithm based on the valve position error to calculate the control current of the drive solenoid coil, so that the valve core gradually approaches the target valve position. When the valve position error meets the preset threshold or the valve core position remains stable within a preset time, the valve action is determined to be completed, and the valve core stroke confirmation and operation status monitoring are completed at the same time.

10. The control method for an intelligent pneumatic solenoid valve with valve position feedback as described in claim 9, characterized in that, Also includes: The S5.MCU feeds back the valve's final action status, valve position information, and operating status to the host computer, enabling remote monitoring and management of the valve's status.

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