Intelligent frequency conversion adjusting type electro-hydraulic actuator control system

Abstract

The utility model provides an intelligent frequency conversion adjusting type electro-hydraulic actuator control system, comprising a power supply and distribution module, an input port of which is connected with an input power supply; the control module is connected with an output port of the power supply and distribution module and comprises a PLC host; the execution module is connected with the output port of the power supply and distribution module and the control module and comprises a frequency converter, a motor and an electro-hydraulic valve serving as an actuator, the frequency converter is used for adjusting the motion state of the motor, and the motor is used for controlling opening and closing of the electro-hydraulic valve; the feedback module is connected with the input port of the control module and is used for inputting a feedback signal to the control module; and the liquid level detection module is used for detecting the liquid level in the closed pipeline and sending liquid level information to the control module. The utility model has the characteristics of rigorous operation logic, short execution time, fast response and the like, and can carry out remote control and automatic control so as to realize unattended operation or few-person operation.

Description

Technical Field

[0001] The utility model relates to a control method of an electro-hydraulic valve, in particular to an intelligent frequency conversion regulation type electro-hydraulic actuator control system. Background Art

[0002] As an important carrier, the safety of high-pressure gas transmission pipelines has attracted increasing attention. Problems such as gas leakage, pipeline damage or poor construction may cause serious consequences at any time, such as fires, explosions, etc. Therefore, it is particularly important to improve the safety of gas pipelines.

[0003] As a kind of hydraulic valve controlled by electromagnetic, the electro-hydraulic valve can be used to control the transmission of gas or liquid pipelines. However, most of the electro-hydraulic valves currently used for controlling pipeline transportation are piston type. The control sensitivity of this kind of electro-hydraulic valve in environments such as high temperature and high pressure is not ideal enough, and it relies on mechanical structures such as springs when opening and closing the valve, and errors and component losses are likely to occur in high-pressure environments. At the same time, in order to control the liquid level in the pipeline to always remain within the set value, the traditional electro-hydraulic valve control system usually requires a large amount of manpower for monitoring work. Content of the Utility Model

[0004] The utility model provides an intelligent frequency conversion regulation type electro-hydraulic actuator control system, which can flexibly and timely adjust the state of the electro-hydraulic valve through an intelligent system, and solves the problems described in the background art.

[0005] The utility model is realized through the following technical solutions:

[0006] An intelligent frequency conversion regulation type electro-hydraulic actuator control system, the system includes:

[0007] A power supply and distribution module, whose input port is connected to an input power supply;

[0008] A control module, connected to the output port of the power supply and distribution module, and includes a PLC host;

[0009] An execution module, connected to the output port of the power supply and distribution module and the control module, includes an inverter, a motor and an electro-hydraulic valve as an actuator, the inverter is used to adjust the motion state of the motor, and the motor is used to control the opening and closing of the electro-hydraulic valve;

[0010] A feedback module, connected to the input port of the control module, and used to input a feedback signal to the control module;

[0011] A liquid level detection module, used to detect the liquid level in a closed pipeline and send the liquid level information to the control module.

[0012] The power supply and distribution module includes an air switch, a fuse and a switching power supply;

[0013] The L - pole input of the air switch is connected to the L - pole of the input power supply, and the L - pole output of the air switch is connected to the L - pole input of the switching power supply;

[0014] The N - pole input of the air switch is connected to the N - pole of the input power supply, and the N - pole output of the air switch is connected to the N - pole input of the switching power supply;

[0015] The fuse is set in the connection circuit between the air switch and the switching power supply to protect the circuit in case of short - circuit or overload.

[0016] The control module includes a host computer with a DCS system and a touch screen for the PLC main - machine control panel.

[0017] The L - pole input port of the PLC main - machine is connected to the L - pole output of the switching power supply, and the M - pole input port of the PLC main - machine is connected to the N - pole output of the switching power supply.

[0018] The L - pole input port of the frequency converter is connected to the L - pole output of the air switch, and the N - pole input port of the frequency converter is connected to the N - pole output of the air switch.

[0019] The feedback module includes a valve - position actuator and a valve - position potentiometer. The valve - position potentiometer is used to detect the position signal of the electro - hydraulic valve and record the state as an electrical signal. The valve - position actuator is used to convert the electrical signal sent by the valve - position potentiometer into a digital signal and send the digital signal to the PLC main - machine.

[0020] The L - pole input of the valve - position actuator is connected to the L - pole output of the switching power supply, and the N - pole input of the valve - position actuator is connected to the N - pole output of the switching power supply.

[0021] The liquid - level detection module includes a liquid - level alarm device. The liquid - level alarm device is connected to the control module. When the liquid level exceeds the alarm threshold, the liquid - level alarm device will send an alarm signal to the control module.

[0022] When the control module is running, it outputs various status signals for the DCS system to monitor. The status signals include valve - position signal, remote - status signal, servo - motor running - status signal, motor - overload signal, comprehensive - fault signal, valve - position 4 - 20mA analog signal.

[0023] The model of the PLC main - machine is Siemens S7 - 200.

[0024] The beneficial effects of the present utility model are as follows: The present utility model features a rigorous operation logic, short execution time, and fast response. It can be remotely controlled or automatically controlled through the PLC host to achieve unmanned or less-attended operation, liberating the labor force. At the same time, the structure that adjusts the motor through the frequency converter to control the opening and closing of the electro-hydraulic valve makes the opening and closing of the electro-hydraulic valve more flexible and accurate. The configured feedback module can also real-time feedback the position information of the electro-hydraulic valve, and can make timely adjustments and corrections when errors occur in the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the module structure of the intelligent variable frequency regulated electro-hydraulic actuator control system;

[0026] Figure 2 It is a circuit topology diagram of the intelligent variable frequency regulated electro-hydraulic actuator control system;

[0027] Figure 3 It is a schematic diagram of the control flow of the intelligent variable frequency regulated electro-hydraulic actuator control system;

[0028] Figure 4 It is a schematic diagram of the operation implementation of the intelligent variable frequency regulated electro-hydraulic actuator control system. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following describes the specific embodiments of the present utility model with reference to the drawings.

[0030] As Figure 1 、 Figure 2 shown, an intelligent variable frequency regulated electro-hydraulic actuator control system, the system includes a power supply and distribution module, a control module, an execution module, a feedback module, and a liquid level detection module.

[0031] The power supply and distribution module includes an air switch, a fuse, and a switching power supply. The L pole input of the air switch is connected to the L pole of the input power supply, and the L pole output of the air switch is connected to the L pole input of the switching power supply; the N pole input of the air switch is connected to the N pole of the input power supply, and the N pole output of the air switch is connected to the N pole input of the switching power supply; the fuse is arranged on the connection circuit between the air switch and the switching power supply to protect the circuit in case of short circuit or overload. The air switch is used to control the power supply of the entire system circuit, and the switching power supply is used to supply power to the control module and the feedback module.

[0032] The control module includes a PLC host, a host computer with a DCS control system, and a touch screen for operating the PLC host. The L-pole input port of the PLC host is connected to the L-pole output of the switching power supply, and the M-pole input port of the PLC host is connected to the N-pole output of the switching power supply. Users can operate the PLC host locally through the touch screen to control the entire system, or remotely operate or automatically operate the PLC host through the DCS control system to control the entire system. When the control module is running, it outputs various status signals for the DCS system to monitor. The status signals include valve position signals, remote status signals, servo motor operating status signals, motor overload signals, comprehensive fault signals, and valve position 4-20 mA analog signals. All of the above status signals are passive dry contact digital signals. At the same time, the control module can communicate with the DCS system through protocols such as RS485, MODBUS, CANOPEN, and ETHERNET.

[0033] The execution module is connected to the output port of the power supply and distribution module and the control module, and includes a frequency converter, a motor, and an electro-hydraulic valve as an actuator. The frequency converter is used to adjust the motion state of the motor, and the motor is used to control the opening and closing of the electro-hydraulic valve. The L-pole input port of the frequency converter is connected to the L-pole output of the air switch, and the N-pole input port of the frequency converter is connected to the N-pole output of the air switch. The motor is connected to the U, V, and M three-phase ports on the frequency converter. The motor controls the electro-hydraulic valve as an actuator to open and close, and the opening and closing state of the electro-hydraulic valve is fed back to the PLC host through an electrical signal.

[0034] The feedback module is connected to the input port of the control module and is used to input feedback signals to the control module. The valve position potentiometer is used to detect the position state of the electro-hydraulic valve and record the state as an electrical signal. The valve position actuator is used to convert the electrical signal sent by the valve position potentiometer into a digital signal and send the digital signal to the PLC host.

[0035] The liquid level detection module is connected to the control module, detects the liquid level in the closed pipeline, and sends the liquid level information to the control module. The liquid level detection module includes a liquid level alarm device. The liquid level alarm device is connected to the control module. When the liquid level exceeds the alarm threshold, the liquid level alarm device sends an alarm signal to the control module.

[0036] Such as Figure 3As shown in the figure, the operation process of the entire intelligent variable-frequency regulated electro-hydraulic actuator control system is as follows. The user issues a command to the PLC host, which contains the final position of the electro-hydraulic valve. After receiving the command, the PLC host controls the frequency converter according to the command. The frequency converter controls the rotation of the servo motor to control the position of the electro-hydraulic valve serving as the actuator. The valve position actuator then feeds back the position of the electro-hydraulic valve to the PLC host and the upper computer. After receiving the signal, the host sends the signal to the DCS control system for analysis and then conducts a new round of control. This process repeats until the position of the electro-hydraulic valve reaches the position set by the user.

[0037] As Figure 4 shown, the motion states of the electro-hydraulic valve can be divided into valve opening and valve closing. The control system can perform manual control or automatic control through PLC calculation.

[0038] The following will describe three control operation implementation cases of the intelligent variable-frequency regulated electro-hydraulic actuator control system.

[0039] Before performing operation control, it is necessary to power on the system and confirm the working state. The steps are as follows:

[0040] Connect the control power supply. The power indicator light turns on. Check whether the CPU and the touch screen display are in the working state;

[0041] The program defaults to the data display state. The touch screen operation display shows "pipeline pressure, air pressure, electro-hydraulic valve liquid level". When powering on for the first time, only when the above detections are within the normal range values can operations be performed. At the same time, it is also necessary to ensure that the above detection values are within the normal range during operation.

[0042] The control operation methods can be divided into local control, remote control, and automatic operation.

[0043] Local control:

[0044] Valve opening: Gently touch the "Mode" key on the touch screen operation display, select the "Local" operation state. At the same time, "Local operation state" is displayed on the touch screen. Gently touch the "Valve opening" key. The CPU issues a command, the frequency converter receives the signal, the servo motor starts, and the valve opens. At the same time, "Valve opening, valve opening stroke" is displayed on the touch screen. At this time, the valve opens to the fully open position at the set speed. The photoelectric position detection switch detects the valve position. The CPU performs calculations, and the valve angle degree is displayed on the touch screen display until it is 100% fully open. When the valve opens to 25 degrees, the "Open twenty-five" signal is sent for remote DCS monitoring.

[0045] Valve closing: In the "local operation state", touch the "Valve closing" button gently. The CPU issues a command. The frequency converter receives the signal, the servo motor starts, and the valve closes. At the same time, "Valve closing, valve closing stroke" is displayed on the touch screen. At this time, the valve closes to the fully closed position at the set speed. The photoelectric position detection switch detects the valve position. The CPU performs calculations, and the degree of the valve angle is displayed on the touch screen monitor until it reaches 0% fully closed. When the valve closes to 75%, the signal "Close seventy-five" is sent for remote DCS monitoring.

[0046] Stop: During the valve opening or closing process, touch the "Stop" button gently, and the valve stops at any intermediate position. At the same time, the text "Valve stopped" is displayed.

[0047] Remote control:

[0048] Valve opening: On-site, gently touch the "Mode" button on the touch screen operation monitor, select the "Remote" operation state. At the same time, "Remote operation state" is displayed on the touch screen. The remote DCS issues a valve opening command. After the CPU receives this signal, it issues a command. The frequency converter receives the signal, the servo motor starts, and the valve opens. At the same time, "Valve opening" is displayed on the touch screen. At this time, the valve opens to the fully open position at the set speed. The photoelectric position detection switch detects the valve position. The CPU performs calculations, and the degree of the valve angle is displayed on the touch screen monitor until it reaches 100% fully open. When the valve opens to 25%, the signal "Open twenty-five" is sent for remote DCS monitoring.

[0049] Valve closing: In the "Remote operation state", the remote DCS issues a "Valve closing" command. After the CPU receives this signal, it issues a command. The frequency converter receives the signal, the servo motor starts, and the valve closes. At the same time, "Valve closing" is displayed on the touch screen. At this time, the valve closes to the fully closed position at the set speed. The photoelectric position detection switch detects the valve position. The CPU performs calculations, and the degree of the valve angle is displayed on the touch screen monitor until it reaches 0% fully closed. When the valve closes to 75%, the signal "Close seventy-five" is sent for remote DCS monitoring.

[0050] Automatic operation:

[0051] Valve opening: The touch screen sets the pipeline flow rate and pipeline pressure and issues an execution command. The CPU receives this signal. After detecting the pipeline pressure and flow rate information of the valve, through PLC calculation, it issues an instruction to the frequency converter. Through the secondary calculation of the frequency converter, the valve opening stroke and valve opening speed are determined, and the starting current of the servo motor is controlled, so as to more accurately control the valve opening.

[0052] Closing the valve: The touch screen sets the pipeline flow rate and pipeline pressure and issues an execution command. The CPU receives this signal. After detecting the pipeline pressure and flow rate information of the valve, through PLC calculation, it issues an instruction to the frequency converter. Through the secondary calculation of the frequency converter, the valve opening stroke and valve closing speed are opened, and the starting current of the servo motor is controlled, so as to more accurately control the valve closing.

[0053] The above content describes the structure, main embodiments and advantages of the present invention. It should be noted that the specific implementation of the present invention is not limited by the above methods. As long as various non-substantive improvements are made by adopting the technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention. The scope of protection required by the present invention is defined by the appended claims and their equivalents.

Claims

1. An intelligent frequency conversion adjustable electro-hydraulic actuator control system, characterized in that, The system includes: A power supply and distribution module, whose input port is connected to an input power supply; A control module, connected to the output port of the power supply and distribution module, and includes a PLC host; An execution module, connected to the output port of the power supply and distribution module and the control module, includes a frequency converter, a motor, and an electro-hydraulic valve as an actuator. The frequency converter is used to adjust the motion state of the motor, and the motor is used to control the opening and closing of the electro-hydraulic valve; A feedback module, connected to the input port of the control module, and is used to input a feedback signal to the control module; A liquid level detection module, used to detect the liquid level in a closed pipeline and send the liquid level information to the control module.

2. The intelligent variable frequency regulated electro-hydraulic actuator control system according to claim 1, characterized in that: The power supply and distribution module includes an air switch, a fuse, and a switching power supply; The L-pole input of the air switch is connected to the L-pole of the input power supply, and the L-pole output of the air switch is connected to the L-pole input of the switching power supply; The N-pole input of the air switch is connected to the N-pole of the input power supply, and the N-pole output of the air switch is connected to the N-pole input of the switching power supply; The fuse is arranged in the connection circuit between the air switch and the switching power supply, and is used to protect the circuit in case of short circuit or overload of the circuit.

3. The intelligent variable frequency regulated electro-hydraulic actuator control system according to claim 1, characterized in that: The control module includes a host computer with a DCS system and a touch screen for the PLC host control panel.

4. The intelligent variable-frequency regulated electro-hydraulic actuator control system according to claim 2, wherein: The L-pole input port of the PLC host is connected to the L-pole output of the switching power supply, and the M-pole input port of the PLC host is connected to the N-pole output of the switching power supply.

5. The intelligent variable-frequency regulated electro-hydraulic actuator control system according to claim 2, wherein: The L-pole input port of the frequency converter is connected to the L-pole output of the air switch, and the N-pole input port of the frequency converter is connected to the N-pole output of the air switch.

6. The intelligent variable-frequency regulated electro-hydraulic actuator control system according to claim 2, characterized in that: The feedback module includes a valve position actuator and a valve position potentiometer. The valve position potentiometer is used to detect the position signal of the electro-hydraulic valve and record the state as an electrical signal. The valve position actuator is used to convert the electrical signal sent by the valve position potentiometer into a digital signal and send the digital signal to the PLC host.

7. An intelligent variable-frequency regulated electro-hydraulic actuator control system according to claim 6, characterized in that: The L-pole input of the valve position actuator is connected to the L-pole output of the switching power supply, and the N-pole input of the valve position actuator is connected to the N-pole output of the switching power supply.

8. An intelligent variable-frequency regulated electro-hydraulic actuator control system according to claim 1, characterized in that: The liquid level detection module includes a liquid level alarm device. The liquid level alarm device is connected to the control module. When the liquid level exceeds the alarm threshold, the liquid level alarm device will send an alarm signal to the control module.

9. The intelligent variable-frequency regulated electro-hydraulic actuator control system according to claim 3, characterized in that: The control module outputs various status signals for the DCS system to monitor during operation. The status signals include valve position signals, remote status signals, servo motor operation status signals, motor overload signals, comprehensive fault signals, and 4-20mA analog signals of valve position.

10. The intelligent variable-frequency regulated electro-hydraulic actuator control system according to claim 1, characterized in that: The model of the PLC host is Siemens S7-200.

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