CN115933463A - Numerical control valve control system with closed-loop feedback control - Google Patents

Abstract

The invention discloses a numerical control valve control system of closed loop feedback control, which relates to the field of numerical control valve control and comprises: the system comprises a central controller, a base layer controller, a man-machine interaction module and a feedback execution module; the central controller is respectively connected with the base layer controller and the man-machine interaction module; the feedback execution module is respectively connected with the base layer controller and the central controller; the human-computer interaction module is used for inputting a control target value of the pipeline valve; the central controller is used for receiving the control target value of the human-computer interaction module and the feedback data of the pipeline valve acquired by the feedback execution module, and calculating the control quantity of the pipeline valve by adopting a feedback control algorithm according to the control target value and the feedback data; a base layer controller for applying a control quantity to the pipeline valve; and the feedback execution module is used for detecting the state of the pipeline valve in real time to obtain feedback data. The invention can realize the accurate control of the pipeline valve, thereby realizing the accurate control of the pipeline valve on the flow and the flow speed of a pipeline system.

Description

A Numerical Control Valve Control System with Closed-loop Feedback Control

technical field

The invention relates to the field of numerical control valve control, in particular to a closed-loop feedback control numerical control valve control system.

Background technique

In the existing valve pipeline systems currently on the market, simple switch control is generally used for valve control, and the control accuracy is low, so it is difficult to achieve high-precision integrated control. For some application scenarios that require high flow control or rate control, it is only Adding a flow quality controller to the pipeline system makes the entire control system appear inconsistent, and application scenarios that require high valve rotation position or torque cannot be realized.

Among the existing embodiments, such as the embodiment with the publication number "CN 107035904A" and the name "double-acting pneumatic actuator-driven automatic valve system that can provide double protection", it mainly relates to an in-line valve system that can provide double protection. The valve system driven by a double-acting pneumatic actuator that automatically opens or closes when the pressure exceeds the set value is mainly aimed at the switching of automatic valves, and does not involve the precise control of the flow and velocity of the pipeline system based on the valve.

Contents of the invention

Based on this, the embodiment of the present invention provides a closed-loop feedback control numerical control valve control system to realize precise control of pipeline valves, thereby realizing precise control of pipeline system flow and velocity by pipeline valves.

To achieve the above object, the present invention provides the following scheme:

A closed-loop feedback control numerical control valve control system, including: a central controller, a basic controller, a human-computer interaction module and a feedback execution module;

The central controller is respectively connected with the basic controller and the human-computer interaction module; the feedback execution module is connected with the basic controller and the central controller respectively;

The human-computer interaction module is used for:

Input the control target value of the pipeline valve; the control target value includes: at least one of the expected rotation position, the expected rotation speed and the maximum current threshold in the expected rotation;

The central controller is used for:

receiving the control target value of the human-computer interaction module and the feedback data of the pipeline valve collected by the feedback execution module;

According to the control target value and the feedback data, a feedback control algorithm is used to calculate the control amount of the pipeline valve;

Wherein, the feedback data includes: at least one of actual rotation position, actual rotation speed and current in actual rotation; the control amount includes: force position control amount, position control amount, speed control amount and torque control at least one of the quantities;

The basic controller is used for:

applying the control amount to the pipeline valve;

The feedback execution module is used for:

The state of the pipeline valve is detected in real time to obtain the feedback data.

Optionally, the central controller includes: a data receiving module and a multi-mode control module;

The data receiving module is used for:

If the current control mode is the force-position mixed control mode, receive the expected rotational position and expected rotational speed sent by the human-computer interaction module, and the actual rotational position and actual rotational speed of the pipeline valve collected by the feedback execution module ;

If the current control mode is the servo position control mode, then receive the expected rotation position, expected rotation speed and maximum current threshold in the expected rotation sent by the human-computer interaction module, and the pipeline valve collected by the feedback execution module Actual rotation position, actual rotation speed and actual rotation current;

If the current control mode is the servo speed control mode, receiving the expected rotation speed sent by the human-computer interaction module and the actual rotation speed of the pipeline valve collected by the feedback execution module;

If the current control mode is the servo torque control mode, then receive the expected rotation position, expected rotation speed and maximum current threshold in the expected rotation sent by the human-computer interaction module, and the pipeline valve collected by the feedback execution module Actual rotation position, actual rotation speed and actual rotation current;

The multi-mode control module has a built-in PD controller and a PI controller for:

If the current control mode is the force-position mixed control mode, then input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and the PD controller sends The force position control amount of the pipeline valve;

If the current control mode is the servo position control mode, then input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and input the output of the PD controller, The maximum current threshold in the expected rotation and the current in the actual rotation are input to the PI controller, and the PI controller applies a position control amount to the pipeline valve through a first PI control algorithm;

If the current control mode is a servo speed control mode, inputting the expected rotation speed and the actual rotation speed into the PD controller, and the PD controller applies a speed control amount to the pipeline valve;

If the current control mode is the servo torque control mode, then input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and input the output of the PD controller, The maximum current threshold in the expected rotation and the current in the actual rotation are input into the PI controller, and the PI controller applies a torque control amount to the pipeline valve through a second PI control algorithm.

Optionally, the closed-loop feedback control numerical control valve control system further includes: an external data measuring device;

The external data measuring device is respectively connected with the central controller and the basic controller;

The external data measuring device is used to obtain environmental data of the environment where the pipeline valve is located, and transmit the environmental data to the human-computer interaction module through the central controller;

Wherein, the environmental data include: temperature and humidity, pressure and vacuum degree;

The human-computer interaction module is used to display the environmental data; the control target value of the pipeline valve is determined according to the environmental data.

Optionally, the human-computer interaction module is also used for:

Input the set maximum torque value, set maximum current and set rotation speed of the pipeline valve;

The central controller is also used for:

When the desired rotation position exceeds the set maximum torque value, the desired rotation speed exceeds the set rotation speed amount, or the maximum current threshold in the desired rotation exceeds the set maximum current, the control The above-mentioned pipeline valve stops operating.

Optionally, the closed-loop feedback control numerical control valve control system further includes: a limit sensor; the limit sensor is set at a rotation limit position of the pipeline valve.

Optionally, the closed-loop feedback control numerical control valve control system also includes: a servo controller and a servo motor;

The primary controller is connected to the servo controller; the servo controller is connected to the pipeline valve through the servo motor; the feedback execution module is connected to the pipeline valve through the servo motor.

Optionally, the central controller is connected to the human-computer interaction module through a network bus.

Optionally, the base controller is connected to the servo controller through a CAN bus.

Compared with prior art, the beneficial effect of the present invention is:

The embodiment of the present invention proposes a closed-loop feedback control CNC valve control system, the system includes: a central controller, a basic controller, a human-computer interaction module and a feedback execution module; the central controller communicates with the basic controller and the human-computer interaction respectively Module connection; the feedback execution module is connected with the primary controller and the central controller respectively, and the central controller obtains the force position control amount, position control amount, and speed control amount according to the control target value and the feedback data of the pipeline valve collected by the feedback execution module At least one of the control amount of torque and torque can realize the precise control of the pipeline valve, so as to realize the precise control of the application scenarios applicable to the pipeline system with high requirements on the flow or rate.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the embodiments. Obviously, the accompanying drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without paying creative labor.

Fig. 1 is the structural diagram of the numerical control valve control system of the closed-loop feedback control that the embodiment of the present invention provides;

Fig. 2 is the schematic structural diagram of the numerical control valve control system of the closed-loop feedback control provided by the embodiment of the present invention;

FIG. 3 is a structural diagram of an actuator provided by an embodiment of the present invention;

Fig. 4 is a control block diagram of the force-position mixed control mode provided by the embodiment of the present invention;

5 is a control block diagram of a servo position control mode provided by an embodiment of the present invention;

Fig. 6 is a structural diagram of the pipeline system provided by the embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The purpose of the present invention is to control the high-precision control and adjustment of valves such as the flow rate, flow rate and pressure of gas and liquid in the pipeline system.

Aiming at the problem of valve control in the pipeline system, a numerical control valve control system with multiple modes of closed-loop feedback control is proposed. The advantage of adopting the present invention is that the closing torque and opening position of the valve can be adjusted through process system presets and external data. The amount of rotation is equal to realize the adjustment of the pressure, speed and flow of the pipeline system to realize the automatic linkage control of multiple valves. The numerical control valve control assembly obtained by the present invention has the characteristics of small size, automatic valve switch control, controllable and adjustable modes such as valve rotational torque and position, controllable and adjustable flow and flow rate in the pipeline, and high control precision by using servo control as the executive component. , especially suitable for high-precision control and adjustment of gas and liquid flow, flow velocity, pressure and other valves in the pipeline system.

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

FIG. 1 is a structural diagram of a closed-loop feedback control numerical control valve control system provided by an embodiment of the present invention. Referring to Fig. 1, the system includes: a central controller, a basic controller, a human-computer interaction module and a feedback execution module.

The central controller is respectively connected with the basic controller and the human-computer interaction module; the feedback execution module is connected with the basic controller and the central controller respectively.

The human-computer interaction module is used to: input the control target value of the pipeline valve; the control target value includes: at least one of the expected rotation position, the expected rotation speed and the maximum current threshold in the expected rotation.

The central controller, as the main controller of the valve control system, is mainly used for feedback data processing, and the calculated control quantity is sent to the basic controller. Specifically, the central controller is configured to: receive the control target value of the human-computer interaction module and the feedback data of the pipeline valve collected by the feedback execution module; Data, using the feedback control algorithm to calculate the control amount of the pipeline valve. The feedback control algorithm may be a PI/PD control algorithm.

Wherein, the feedback data includes: at least one of actual rotation position, actual rotation speed and current in actual rotation; the control amount includes: force position control amount, position control amount, speed control amount and torque control at least one of the quantities. The man-machine interface (operating interface) on the man-machine interaction module can display system control status, control quantity, initial value input (target value) and so on.

The primary controller takes the control quantity of the central controller as input, and precisely controls the pipeline valve as an actuator based on the control quantity. Therefore, the primary controller is configured to: apply the control amount to the pipeline valve.

The feedback execution module is configured to: detect the state of the pipeline valve in real time to obtain the feedback data. The feedback execution module includes an actuator and a feedback part; the pipeline valve can be used as the actuator; the feedback part can be a feedback sensor installed at the end of the pipeline valve to detect the opening accuracy of the management valve and obtain feedback data.

The central controller has control modes such as automatic execution and manual execution. Under the automatic execution program, the central controller includes force-position mixed control mode, servo position control mode, servo speed control mode and servo torque (current) control mode , according to the demand to select the appropriate control mode, to achieve pipeline valve control. The control program can also realize functions such as pausing, using absolute coordinates and incremental coordinates to control the valve position, etc.

The man-machine interaction module is connected with the central controller through the network bus, and can transmit the current data of the system to the man-machine interface for display, and can select the automatic mode or the manual mode on the man-machine interface.

In one example, in the automatic control mode, under the feedback control algorithm of the central controller, the current The control quantity output by the central controller, the grassroots controller automatically realizes the multi-valve independent or linkage function after receiving the control quantity of the central controller.

In the manual control mode, the operator inputs the rotation position or torque of each valve in the system through the man-machine interface, and manually controls the opening and closing of the valve by jogging.

Specifically, the central controller includes: a data receiving module and a multi-mode control module.

Among them, the data receiving module is mainly used to read the feedback data, and the feedback data is used as the input of the multi-mode control module. The data receiving module also has a communication interface with the human-computer interaction module. The central controller can exchange information with the human-computer interaction module through the communication port, and can also establish a communication connection with the external network.

Specifically, the data receiving module is used for:

If the current control mode is the force-position mixed control mode, receive the expected rotational position and expected rotational speed sent by the human-computer interaction module, and the actual rotational position and actual rotational speed of the pipeline valve collected by the feedback execution module .

If the current control mode is the servo position control mode, then receive the expected rotation position, expected rotation speed and maximum current threshold in the expected rotation sent by the human-computer interaction module, and the pipeline valve collected by the feedback execution module Actual rotational position, actual rotational speed and actual rotational current.

If the current control mode is the servo speed control mode, receiving the expected rotation speed sent by the human-computer interaction module and the actual rotation speed of the pipeline valve collected by the feedback execution module.

If the current control mode is the servo torque (current) control mode, then receive the expected rotation position, expected rotation speed and maximum current threshold in the expected rotation sent by the human-computer interaction module, and the tube collected by the feedback execution module The actual rotation position, actual rotation speed and actual rotation current of the circuit valve.

Wherein, the multi-mode control module has a built-in PD controller and a PI controller. Specifically, the multi-mode control module is used for:

1) If the current control mode is force-position mixed control mode, then input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and the PD controller A force level control amount is applied to the pipeline valve.

2) If the current control mode is the servo position control mode, then input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and input the output of the PD controller The quantity, the maximum current threshold in the expected rotation and the current in the actual rotation are input to the PI controller, and the PI controller applies a position control quantity to the pipeline valve through a first PI control algorithm.

3) If the current control mode is the servo speed control mode, input the expected rotation speed and the actual rotation speed into the PD controller, and the PD controller applies a speed control amount to the pipeline valve.

4) If the current control mode is the servo torque control mode, input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and input the output of the PD controller The amount, the maximum current threshold in the expected rotation and the current in the actual rotation are input to the PI controller, and the PI controller applies a torque control amount to the pipeline valve through a second PI control algorithm.

In another example, the closed-loop feedback control numerical control valve control system further includes: an external data measuring device.

The external data measuring device is respectively connected with the central controller and the basic controller; the external data measuring device is used to obtain the environmental data of the environment where the pipeline valve is located, and pass the environmental data through the The central controller transmits to the human-computer interaction module; wherein, the environmental data includes: temperature and humidity, pressure and vacuum degree.

The control quantity output by the central controller is under the feedback control algorithm, and each pipeline valve obtained according to the initial value (or target value) set by the pipeline process and external data (pressure, vacuum degree, etc.) needs to be automatically adjusted in real time Valve "opening" or rotational position. Specifically, the central controller adjusts the valve rotation opening and position automatically in real time according to the initial value set by the pipeline system process and external data, and realizes automatic control of the pressure rate or flow of the pipeline system based on the matching relationship between the two.

The basic-level controller takes the control quantity of the central controller as input, and precisely controls the actuator based on the control quantity (for example, based on the control quantity of the central controller, the basic-level controller acts on the servo controller to automatically control the opening and closing of the pipeline valve, Make the pipeline system complete the process required pressure rate or flow), the basic controller acts as a link between the actuator and the central controller, and includes the functions of receiving, decoding and sending control data; at the same time, it can decode the central controller The "I/O" signal command is used to control the switching value of the peripherals of the system, realize the start-stop control of temperature, humidity, pressure, vacuum, etc., and feed back the current state quantity (current environmental data) to the central controller.

The human-computer interaction module is used to display the environmental data; the control target value of the pipeline valve is determined according to the environmental data.

In another example, referring to FIG. 2 , the closed-loop feedback control numerical control valve control system further includes: a servo controller and a servo motor. The structures in the dotted box in Figure 2 are mechanically connected.

The primary controller is connected to the servo controller; the servo controller is connected to the pipeline valve through the servo motor; the feedback execution module is connected to the pipeline valve through the servo motor. In this example, the servo controller, servo motor and pipeline valve constitute the actuator. As shown in Figure 3, the servo motor 1 is mechanically connected to the main body of the pipeline valve 2, the servo controller is connected to the servo motor through a cable, and the feedback sensor Installed at the end of the servo motor 1.

The actuator can also be composed of multiple sets of servo controllers, multiple sets of servo motors and multiple sets of pipeline valves; the number of axes of the actuator can be increased in series/parallel according to the requirements of the pipeline system, and the servo controller and the basic controller Based on the CAN bus connection, the control data is transmitted to the multi-axis servo controller (composed of multiple servo controllers), and then directly controls the rotation of the servo motor in the actuator component.

The central controller is connected to the human-computer interaction module through a network bus.

The basic controller is connected with the servo controller through a CAN bus. The basic-level controller is the "lower-level" controller of the central controller, which receives the control amount of the central controller, connects the actuator through the CAN bus, controls the rotational torque/position/speed of the pipeline valve, and transmits it in real time through the feedback sensor. Feedback data (valve real-time rotation data) is sent back to the central controller.

The feedback part in the feedback execution module is mechanically connected and installed with the actuator to directly detect the rotation position angle of the valve, realize the detection of the "opening degree" of the valve, and then accurately adjust the flow rate of the system.

In yet another example, the human-computer interaction module can set initial values such as overload protection, limit protection, current (torque) adjustment, valve rotation speed, etc., or set the target value of the valve system and send it to the central controller .

Specifically, the human-computer interaction module is also used for: inputting the set maximum torque value, set maximum current and set rotation speed of the pipeline valve.

The central controller is further configured to: when the desired rotation position exceeds the set maximum torque value, the desired rotation speed exceeds the set rotation speed amount, or the maximum current threshold in the desired rotation exceeds When the maximum current is set, the pipeline valve is controlled to stop running.

Wherein, the numerical control valve control system of the closed-loop feedback control further includes: a limit sensor; the limit sensor is set at the rotation limit position of the pipeline valve.

In this example, the central controller has protection functions such as overload protection, limit protection, current (torque) adjustment, and valve rotation speed setting.

In the above-mentioned embodiments, according to different requirements of the pipeline system and process, the combination programming operation of any valve can be realized, and the combination of each valve is flexible and variable; the control system can accurately realize the torque control when the valve is closed/opened through the current mode; the control system The position control when the valve is closed/opened can be accurately realized through the position mode.

The CNC valve control system with closed-loop feedback control in this embodiment supports multi-valve linkage control, and adjusts valve closing torque, opening position and other rotations based on process system presets and external data to realize the pressure, speed, and flow of the pipeline system. and other adjustments to realize multi-valve automatic linkage control. The numerical control valve control assembly obtained in this example has the advantages of small size, automatic valve switch control, controllable and adjustable modes such as valve rotational torque and position, controllable and adjustable flow rate and flow rate in the pipeline, and adopts servo control as the executive component to control the accuracy. Advanced features, especially suitable for high-precision automatic control and adjustment of gas and liquid flow, flow rate, pressure and other valves in pipeline systems.

Several specific embodiments are given below to further describe the above-mentioned closed-loop feedback control numerical control valve control system in detail.

Specific embodiment 1:

In the numerical control valve control system of multi-mode closed-loop feedback control in this specific example, the central controller is the main control part of the numerical control valve control system, which is mainly composed of a data receiving module and a multi-mode control module; the multi-mode control module is mainly for valves. Precise control algorithm, the data receiving module receives and decodes the feedback quantity of the system, which is used as the input of the control algorithm. The PI/PD control algorithm of the multi-mode control module compares the feedback data collected by the feedback sensor with the valve control target value as input, and the control amount calculated by the algorithm is sent to the basic controller through the CAN bus; and the data receiving module Receive and read the feedback data, and use the feedback data as the input of the multi-mode control module. At the same time, it has a communication interface with the human-machine interface. The central controller interacts with the information of the human-machine interface through the communication port, and can also establish a communication connection with the external network. .

In the CNC valve control system, the man-machine interface is used to display the control system control quantity and status data information in real time, and is connected to the central controller. The central controller transmits the data to the man-machine interface for display, and the operator outputs the initial value or controls on the interface value; in this embodiment, the man-machine interface is a touch-screen display that can be operated by touch, can be displayed, and is connected to the central controller based on the network bus protocol.

The basic controller is the sub-control of the CNC valve control system, which is "serialized" between the actuator and the central controller, including the functions of receiving, decoding and sending control data. Connect the servo controller based on the CAN bus, and directly control the valve rotation torque/position/speed according to the control quantity obtained by decoding, and transmit the real-time rotation data of the valve back to the central controller through the feedback part. The basic controller can directly act on each servo controller to control the valve to realize multi-valve independent or linkage function; according to the control initial value (man-machine interface setting) and external data (pressure, vacuum degree, etc.) set according to the process of the pipeline system Adjust the valve rotation "opening and closing amount" and position.

The feedback part is mechanically connected with the actuator part. The feedback sensor is installed at the rear end of the motor, and the motor and the valve are connected through a coupling. Therefore, the sensor can directly detect the rotation position angle and rotation speed of the valve, and realize the detection of the "opening and closing amount" of the valve. And then precisely adjust the system flow rate.

Based on the above-mentioned system control relationship, this specific embodiment describes the force-position mixed control mode, servo position control mode, and servo speed control mode in the numerical control valve control system.

(1) In the implementation of force-position mixed control mode, the human-machine interface first selects the force-position mixed control mode. At this time, in the control module of the central controller, the control algorithm called is the PD control algorithm, as shown in Figure 4. As shown in Figure 4, in the implementation of force-position mixed control mode, the input is the target value P of the human-computer interaction module (desired rotational position pos_desired, desired rotational speed spd__desired), and the actual value P ₀ of the feedback part (actual rotational position pos_current , the actual rotation speed spd_current), and the force position control value motor_current1 is obtained through the PD controller, and finally output to the servo motor, as shown in the following formula:

motor_current1=

KP*(pos_desired-pos_current)+

KD*(spd_desired-spd_current)+Torque/K _T

Among them, KP is the feedback compensation gain; KD is the damping coefficient, KP and KD can determine the appropriate value based on the system debugging process; K _T is the motor torque constant; Torque is the motor torque.

(2) As shown in Figure 5, in the implementation of the servo position control mode, the human-machine interface first selects the servo position control mode, and in the control module of the central controller, the control algorithm called is PI/PD double closed-loop control, see Fig. 5. In this mode, its main input is the actual rotation position and actual rotation speed of the feedback part; the outer loop is position loop control, which is actually a PD controller; the inner loop is a current loop, and the current loop is mainly a PI controller. The input is the output of the PD controller and the current in actual rotation. The parameters in the PD controller and PI controller cannot be changed by the user. In this servo position control mode, in the human-machine interface, it needs three input expected parameters, namely the desired rotational position pos_desired, the desired rotational speed spd__desired and the maximum current threshold I _max in the desired rotational speed, that is, the motor controls the valve from the current position P0 rotates to the desired rotation position pos_desired; during the process from P0 to pos_desired, the maximum current of the motor is I _max , and the maximum torque generated = I _max * motor torque constant K _T , if the encountered load exceeds this torque, the motor will stall. In the servo position control mode, the position control value motor_current2 is obtained through the PD controller and PI controller, and finally output to the servo motor. Based on the output motor_current of the PD controller, the PI controller adopts the first PI control algorithm to obtain the position control value motor_current2, and its formula is expressed as:

Among them, motor_current represents the output of the PD controller, that is, the current value I _c ; motor_current2(t+1) represents the position control value at time t+1; motor_current2(t) represents the position control value at time t, which is essentially t The current I _m in the actual rotation at the moment, I _m ≤ I _max ; KI is the integral time constant. The calculation formula of motor_current is:

(3) In the implementation of the servo speed control mode, the man-machine interface selects the servo speed control mode, and in the control module of the central controller, the control algorithm called is the PD controller. In this embodiment, the input is the actual rotation speed spd_current of the feedback part, and at the same time input the desired rotation speed spd__desired in the human-machine interface, and obtain the speed control value motor_current3 through PI control, and finally output the current to the servo motor. This mode of control is the same as The force-position mixed control mode is consistent, and its formula is expressed as: .

(4) In the implementation of the servo torque control mode, the man-machine interface selects the servo torque control mode, and in the control module of the central controller, the control algorithms called are PI controller and PD controller. In this embodiment, the PD controller outputs the control quantity motor_current, the input of the PI controller is motor_current, the current in the actual rotation of the feedback part, and the maximum current threshold I _max in the expected rotation input by the man-machine interface, and is controlled by PI Get the torque control value motor_current4, and finally output it to the servo motor. The PI controller is based on the output quantity motor_current of the PD controller, and uses the second PI control algorithm to obtain the position control quantity motor_current4, and its formula is expressed as:

Wherein, motor_current represents the output of the PD controller, and the specific calculation formula is the same as that of the servo position control mode, and will not be repeated here. motor_current4(t+1) indicates the torque control amount at time t+1; motor_current4(t) indicates the torque control amount at time t, which is essentially the current I _m in actual rotation at time t, and _Im ≤ I _max .

It should be noted that all the control quantities (force-position control quantity, position control quantity, speed control quantity, and torque control quantity) in the above-mentioned several implementations are currents. In this embodiment, various controllers are used to obtain the most Appropriate current control amount, and then control the motor through the motor driver to obtain appropriate torque (servo torque control mode) or position (servo position control mode). Therefore, all mode control quantities are essentially current to control the motor, but the "target quantity" required for precise control is different in different modes. That is, in the servo torque control mode, the torque is used as the judgment condition; in the servo position control mode, the position is used as the judgment condition.

The above several implementation modes are implementation cases in the automatic mode of the numerical control valve control system. In this implementation case, the automatic mode is selected on the man-machine interface, or the initial state of the numerical control valve control system is the automatic mode. According to different implementations of the central controller, the control quantity is obtained, sent to the basic controller, and then sent to the single or multiple valves of the actuator part for system flow or rate control after analysis. In the automatic mode, each valve obtained according to the initial value (or target value) set by the pipeline process and external data (pressure, vacuum degree, etc.) needs to automatically adjust the "opening and closing amount" or rotation position of the valve in real time, and the central control The controller automatically controls the opening and closing of the valve according to the set rate or flow, so that the pipeline system can complete the pressure, rate or flow required by the process.

Specific embodiment 2:

As another specific implementation case of the present invention, this implementation case discloses the manual mode of the numerical control valve control system. In the manual mode, any valve in the pipeline system can be opened and closed on the man-machine interface, that is, any valve in the system can be "jogged" through the man-machine interface of the numerical control valve control system; at the same time, it can be set based on the man-machine interface The expected value of valve "opening and closing" directly controls the rotation angle of the valve through the central controller and the grass-roots controller, so as to control the flow of the pipeline system. In this implementation case, in manual mode, after setting the desired flow parameters through the man-machine interface and combining external data (pressure, vacuum, etc.), the rate or flow of gas or liquid flowing through the valve can be set, and the central controller can Constant speed or flow rate, control the opening and closing of the valve position to complete the process requirements.

Specific embodiment 3:

As another specific implementation case of the present invention, this implementation case discloses protection functions such as overload protection, limit protection, current (torque) adjustment, and valve rotation speed setting of the numerical control valve control system. In the implementation case, the system overload protection is mainly to set the maximum torque value of the valve opening and closing on the man-machine interface. When the maximum torque of the motor operates the value, the motor stops moving and the system is in the state of overload protection. System lifetime. The limit protection is to set a limit sensor at the limit position of the motor-driven valve rotation to ensure that the valve rotation does not exceed the limit and protect the overall valve control system. Current (torque) adjustment, valve rotation speed setting, etc. are set on the man-machine interface to set the maximum current and rotation speed. When the set expected value exceeds the setting, the system will automatically judge that there is an error and stop running. Protect the overall valve numerical control system. In this implementation case, it is also stipulated that the system encounters "out of control, valve rotation overrun or other emergency state", and the operator can realize the emergency stop of the whole system through the emergency stop button.

Specific embodiment 4:

As another specific implementation case of the present invention, this implementation case discloses the pipeline of the gas mixing system as shown in Figure 6, which can be precisely controlled based on the numerical control valve system of this embodiment, and MFC in Figure 6 is a mass flow controller , SV is the structure composed of pipeline valves and servo motors in the actuator part. In the implementation case shown in Figure 6, 3 gas inputs and 4 gas outputs are arranged. In actual cases, based on this embodiment, the numerical control valve system can be expanded to meet multiple (not less than 16) gas input/output Function. In the implementation case, the flow input/output of the control system is controlled based on the numerical control valve control system, and the current pipeline flow is fed back to the central controller based on the mass flow controller, and then the precise control of each gas flow is further realized through the basic controller; The precise "opening and closing" and rotational torque of the system valve can also be realized through the feedback part. At the same time, in the implementation case, through the precise control of the flow rate, the precise proportion of the gas inside the gas mixing tank can be mixed to obtain the target gas with precise proportion and composition.

The numerical control valve control system of the present invention realizes precise control for application scenarios with high requirements for flow rate or rate in the pipeline system, and the rotational torque and position are controllable and adjustable, and the control system can be adaptively set and adjusted through external input, Can output signals to control external devices, friendly man-machine interface, simple operation interface, etc. Based on the multi-mode valve control, the present invention solves the problem of high precision control and adjustment of the flow, velocity and pressure of the pipeline system, ensures controllable and adjustable valve torque and position, improves the control precision of the pipeline system and adds control modes.

The numerical control valve control system of the closed-loop feedback control of the present invention has the following advantages:

1. The present invention forms a control operation closed loop through the man-machine interface, central controller, basic controller, actuator and feedback part, which can realize the precise control of the gas or liquid flow and rate circulating in the valve, and realize the control of the valve opening and closing state. Precise adjustment, and then precise control of the piping system where the valve is located.

2. The present invention has multiple modes, including force-position mixed control mode, servo position mode, and current (torque) control mode. Select an appropriate control mode according to requirements to realize valve control. At the same time, the control system also has an automatic execution mode and a manual execution mode to ensure that the valve control and system flow control can also be completed through the manual mode when an "error" occurs in the automatic mode.

3. The present invention can realize the start-stop control of external temperature and humidity, pressure, vacuum and other state quantities, and output the state feedback to the central controller, and then act on the actuator to realize precise control of the valve based on the above state quantities.

4. The valve of the actuator of the present invention is controlled by a full servo motor, with high rotation accuracy and movement accuracy of ±5 μm, and the "opening and closing amount" of the valve or the torque and position of rotation are controllable and adjustable.

5. The central controller of the present invention can support the multi-valve linkage function, which can control multiple valves to open and close at the same time; and the central controller and the basic controller can support multi-axis expansion of the actuator, that is, support series/parallel connection to increase the axis of the actuator Number, and then realize the function expansion of the piping system.

6. The control system of the present invention can realize the combination programming operation of any valve according to different requirements such as pipeline system and process, and the combination of each valve is flexible; at the same time, it can be based on external data (pressure, vacuum degree, etc.) under the control algorithm, etc. The obtained valves need to automatically adjust the "opening and closing amount" or the rotation position of the valves in real time.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

In this paper, specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the core idea of the present invention; meanwhile, for those of ordinary skill in the art, according to the thought of the present invention, There will be changes in specific implementation methods and application ranges. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims (8)

1. A numerically controlled valve control system of closed-loop feedback control, characterized in that, comprising: a central controller, a basic controller, a human-computer interaction module and a feedback execution module; The central controller is respectively connected with the basic controller and the human-computer interaction module; the feedback execution module is connected with the basic controller and the central controller respectively; The human-computer interaction module is used for: Input the control target value of the pipeline valve; the control target value includes: at least one of the expected rotation position, the expected rotation speed and the maximum current threshold in the expected rotation; The central controller is used for: receiving the control target value of the human-computer interaction module and the feedback data of the pipeline valve collected by the feedback execution module; According to the control target value and the feedback data, a feedback control algorithm is used to calculate the control amount of the pipeline valve; Wherein, the feedback data includes: at least one of actual rotation position, actual rotation speed and current in actual rotation; the control amount includes: force position control amount, position control amount, speed control amount and torque control at least one of the quantities; The basic controller is used for: applying the control amount to the pipeline valve; The feedback execution module is used for: The state of the pipeline valve is detected in real time to obtain the feedback data. 2. The numerical control valve control system of a kind of closed-loop feedback control according to claim 1, is characterized in that, described central controller comprises: data receiving module and multimode control module; The data receiving module is used for: If the current control mode is the force-position mixed control mode, receive the expected rotational position and expected rotational speed sent by the human-computer interaction module, and the actual rotational position and actual rotational speed of the pipeline valve collected by the feedback execution module ; If the current control mode is the servo position control mode, then receive the expected rotation position, expected rotation speed and maximum current threshold in the expected rotation sent by the human-computer interaction module, and the pipeline valve collected by the feedback execution module Actual rotation position, actual rotation speed and actual rotation current; If the current control mode is the servo speed control mode, receiving the expected rotation speed sent by the human-computer interaction module and the actual rotation speed of the pipeline valve collected by the feedback execution module; If the current control mode is the servo torque control mode, then receive the expected rotation position, expected rotation speed and maximum current threshold in the expected rotation sent by the human-computer interaction module, and the pipeline valve collected by the feedback execution module Actual rotation position, actual rotation speed and actual rotation current; The multi-mode control module has a built-in PD controller and a PI controller for: If the current control mode is the force-position mixed control mode, then input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and the PD controller sends The force position control amount of the pipeline valve; If the current control mode is the servo position control mode, then input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and input the output of the PD controller, The maximum current threshold in the expected rotation and the current in the actual rotation are input to the PI controller, and the PI controller applies a position control amount to the pipeline valve through a first PI control algorithm; If the current control mode is a servo speed control mode, inputting the expected rotation speed and the actual rotation speed into the PD controller, and the PD controller applies a speed control amount to the pipeline valve; If the current control mode is the servo torque control mode, then input the expected rotational position, the expected rotational speed, the actual rotational position and the actual rotational speed into the PD controller, and input the output of the PD controller, The maximum current threshold in the expected rotation and the current in the actual rotation are input into the PI controller, and the PI controller applies a torque control amount to the pipeline valve through a second PI control algorithm. 3. The numerical control valve control system of a kind of closed-loop feedback control according to claim 1, is characterized in that, also comprises: external data measuring device; The external data measuring device is respectively connected with the central controller and the basic controller; The external data measuring device is used to obtain environmental data of the environment where the pipeline valve is located, and transmit the environmental data to the human-computer interaction module through the central controller; Wherein, the environmental data include: temperature and humidity, pressure and vacuum degree; The human-computer interaction module is used to display the environmental data; the control target value of the pipeline valve is determined according to the environmental data. 4. The numerical control valve control system of a kind of closed-loop feedback control according to claim 1, is characterized in that, described human-computer interaction module is also used for: Input the set maximum torque value, set maximum current and set rotation speed of the pipeline valve; The central controller is also used for: When the desired rotation position exceeds the set maximum torque value, the desired rotation speed exceeds the set rotation speed amount, or the maximum current threshold in the desired rotation exceeds the set maximum current, the control The above-mentioned pipeline valve stops operating. 5 . The numerically controlled valve control system with closed-loop feedback control according to claim 1 , further comprising: a limit sensor; and the limit sensor is set at a rotation limit position of the pipeline valve. 6 . 6. The numerical control valve control system of a kind of closed-loop feedback control according to claim 1, is characterized in that, also comprises: servo controller and servo motor; The primary controller is connected to the servo controller; the servo controller is connected to the pipeline valve through the servo motor; the feedback execution module is connected to the pipeline valve through the servo motor. 7. A numerically controlled valve control system with closed-loop feedback control according to claim 1, wherein the central controller is connected to the human-computer interaction module through a network bus. 8 . A closed-loop feedback control numerical control valve control system according to claim 6 , wherein the basic controller is connected to the servo controller through a CAN bus.

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