Control system and method for high-low bypass fault position-keeping multifunctional pneumatic actuating mechanism

Abstract

The invention discloses a control system and method for a high-low bypass fault position-keeping multifunctional pneumatic actuating mechanism. Comprising a filtering pressure reducing valve, an oil mist separator, a double-acting air cylinder, an intelligent valve positioner, an electromagnetic valve, an air lock valve, an air control valve, a flow amplifier and a connecting pipeline. The intelligent valve positioner is directly connected with the double-acting air cylinder through the action conversion module, and the operation state of the double-acting air cylinder can be detected more visually. In addition, the air lock valve, the pneumatic control valve and the electromagnetic valve are connected to realize a position keeping state during a fault period. According to the high-low bypass fault position-keeping multifunctional pneumatic actuating mechanism control system, the service life of a control element is prolonged, the potential safety hazard of misoperation in the fault period is reduced, and the system is more convenient, safer, time-saving and labor-saving.

Description

Technical Field

[0001] The invention relates to the field of pneumatic control, and in particular to a high-low bypass fault-protection multifunctional pneumatic actuator control system and method. Background Art

[0002] In power plants, high and low bypasses play important roles: protecting reheaters, improving startup conditions, accelerating startup speed, recovering working fluids, eliminating noise, realizing medium-pressure cylinder startup, etc. Traditional pneumatic actuators require on-site human intervention during maintenance and failures, which increases the operating time of faulty units, increases the probability of damage to control components, increases the difficulty of maintenance, and has serious consequences due to on-site misoperation.

[0003] Therefore, this application proposes a high-low bypass fault-protection multifunctional pneumatic actuator control system to solve the above problems and further optimize Summary of the invention

[0004] The purpose of the present invention is to provide a high and low bypass fault-keeping multifunctional pneumatic actuator control system to solve the problems raised in the above background technology that during high and low bypass maintenance and faults in power plants, on-site maintenance may result in misoperation, long operating time of faulty units, reduced component service life, great difficulty in maintenance, long response time and accompanying safety hazards.

[0005] To achieve the above object, the present invention provides the following technical solutions: A high-low bypass fault-protection multifunctional pneumatic actuator control system, characterized in that an air source is connected to a filter pressure reducing valve (AFR) and an oil mist separator (AM) through a main pipeline, the main pipeline is divided into a first branch, a second branch and a third branch, the first branch is connected to the air inlet end of an intelligent valve positioner (P), the first branch is connected to an air inlet pipeline and an air outlet pipeline, and the air inlet end and the air outlet end of a double-acting cylinder (A) are connected through pipelines, an air lock valve (D1), an air control valve (D3) and a first flow amplifier (AV1) are connected in series in sequence in the air inlet pipeline, and a second branch is connected to a third branch in sequence in the air outlet pipeline. The second branch is connected in series with an air lock valve (D2), an air control valve (D4), and a second flow amplifier (AV2). The first flow amplifier (AV1) and the second flow amplifier (AV2) are respectively connected to the connecting pipeline of the intelligent valve positioner (P); the second branch is connected to the air lock valve (D), and the air lock valve (D) is respectively connected to the control of the air lock valves (D1) and (D2); the third branch is connected to the solenoid valve (YV), and the control end of the solenoid valve (YV) is respectively connected to the control end of the air control valve (D3) and (D4), and the exhaust port of the air control valve (D4) is connected to the third branch.

[0006] The intelligent valve positioner (P) receives a control signal from the DCS, so that the OUT1 and OUT2 sides of the intelligent valve positioner (P) discharge or exhaust gas, and controls the double-acting cylinder (A) to extend or retract the piston rod through the connecting pipeline, the air lock valve (D), the air lock valves (D1), (D2), and the air control valves (D3), (D4).

[0007] The intelligent valve positioner (P) is directly mounted on the double-acting cylinder (A), which is convenient for on-site operation and assembly.

[0008] The intelligent valve positioner (P) is a position-holding type intelligent valve positioner.

[0009] The filter pressure reducing valve and the oil mist separator are connected with the intelligent valve positioner, the air lock valve and the solenoid valve through the joint pipeline; the intelligent valve positioner is connected with the flow amplifier through the connecting pipeline; the amplifier, the air control valve and the air lock valve are connected with the double-acting cylinder to form a complete control system.

[0010] The control circuit composed of the filter pressure reducing valve, oil mist separator, double-acting cylinder, intelligent valve positioner, solenoid valve, air lock valve, air control valve and amplifier can be increased or reduced according to actual conditions to achieve on-site function realization, thereby increasing the adaptability to various on-site working conditions.

[0011] The intelligent valve positioner is directly mounted on the double-acting cylinder, which is convenient for disassembly, assembly and on-site maintenance.

[0012] The filter pressure reducing valve and the oil mist separator are equipped to purify the impurities and moisture in the gas source to the greatest extent, thereby protecting the intelligent valve positioner to the greatest extent and increasing its service life.

[0013] The air lock valve and the air control valve are overlapped with each other, so that the connecting pipeline is more concise and the air path is clearer.

[0014] The technical solution provided by the embodiment of the present invention may include the following beneficial effects: 1. The equipment is concise, clear, beautiful and elegant, and on-site construction, installation and debugging are more convenient 2. The high and low bypass fault retention multifunctional pneumatic actuator control system has a shorter response time than manual response under special circumstances. The existing retention state can facilitate fault troubleshooting, reduce crisis operation under fault conditions, and protect the safety of on-site operators. 3. The high and low bypass fault-proof multifunctional pneumatic actuator control system can cope with a variety of on-site working conditions. By adding or reducing components, it can realize functions such as quick opening and quick closing in addition to position preservation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1It is a schematic diagram of the connection structure of each device of the present invention. DETAILED DESCRIPTION

[0017] See also Figure 1 .

[0018] A high-low bypass fault-protection multifunctional pneumatic actuator control system, wherein an air source is connected to a filter pressure reducing valve AFR and an oil mist separator AM through a main pipeline, and the main pipeline is divided into a first branch, a second branch and a third branch, wherein the first branch is connected to an air inlet end of an intelligent valve positioner P, and the first branch is connected to an air inlet pipeline and an air outlet pipeline, respectively, and is connected to an air inlet end and an air outlet end of a double-acting cylinder A through pipelines, wherein an air lock valve D1, an air control valve D3 and a first flow amplifier AV1 are sequentially connected in series in the air inlet pipeline, and an air lock valve D2, an air control valve D4 and a second flow amplifier AV2 are sequentially connected in series in the air outlet pipeline, and the first flow amplifier AV1 and the second flow amplifier AV2 are respectively connected to a connecting pipeline of the intelligent valve positioner P; the second branch is connected to an air lock valve D, and the air lock valve D is respectively connected to control connections of air lock valves D1 and D2; the third branch is connected to an electromagnetic valve YV, and the control end of the electromagnetic valve YV is respectively connected to the control ends of air control valves D3 and D4, and the exhaust port of the air control valve D4 is connected to the third branch.

[0019] The intelligent valve positioner P receives the control signal from the DCS to make the intelligent valve positioner POUT1, OUT2 side discharge or exhaust gas, and controls the double-acting cylinder A to extend or retract the piston rod through the connecting pipeline, air lock valve D, air lock valve D1, D2, air control valve D3, D4.

[0020] The intelligent valve positioner P is directly mounted on the double-acting cylinder A, which is convenient for on-site operation and assembly.

[0021] The intelligent valve positioner P is a position-keeping type intelligent valve positioner.

[0022] Note: UE; US; SE; SU are only the gas inflow and outflow directions 1. Valve status: hold position (piston rod retracts and valve opens) In working gas source: loss of gas, control signal: any, YV: any When there is no working gas source, each control element in the system is in the initial state, no gas flows into the cylinder, and the cylinder is in a holding position state.

[0023] 2. Valve status: open (piston rod retracts to open the valve) In working gas source: normal, control signal: arbitrary, YV: power off Overview: The working air source flows through the filter pressure reducing valve AFR, through the air control valve D4 to the air lock valve D2 and enters the cylinder on the shaft side. The gas in the cylinder on the non-shaft side flows through the air lock valve D1 to the air control valve D3 muffler and is discharged.

[0024] Specifically: The working gas source is divided into 4 paths through the filter pressure reducing valve AFR and enters the control system circuit: Act on the gas lock valve D so that the working gas source forms a passage through the US port on the gas lock valves D1 and D2; Acting on the solenoid valve YV passage port passage termination; Acting on the position-holding intelligent valve positioner P, it flows into the amplifier AV through OUT1 and OUT2, and the passage in the S port of the air control valve D3 and D4 through the amplifier AV is closed; 4) The gas flows through the EU port of the air control valve D4 to the SU port of the air lock valve D2 and enters the cylinder on the shaft side. The gas in the cylinder on the non-shaft side flows through the US port of the air lock valve D1 to the muffler of the UE port of the air control valve D3 and is discharged.

[0025] 3. Valve status: hold position (piston rod retracts and valve opens) In working gas source: normal, control signal: lost signal, YV: energized Overview: The working air source flows into the amplifier AV through the filter pressure reducing valve AFR, and then flows through the air control valves D3, D4 and the air lock valves D1, D2 from both sides into the non-shaft side and the shaft side of the cylinder, at this moment forming a position retention state.

[0026] Specifically: The working gas source is divided into 4 paths through the filter pressure reducing valve AFR and enters the control system circuit: Act on the gas lock valve D so that the working gas source forms a passage through the US port on the gas lock valves D1 and D2; Acting on the solenoid valve YV, at this time, after the solenoid valve YV is energized to form a passage at port 31, the gas source flows out and acts on the gas control valves D3 and D4 to form a passage at their ports SU; 3) It acts on the position-holding intelligent valve positioner P, but at this moment it is in the signal-losing state, and OUT1 and OUT2 are not exhausted. The working gas source flows directly into the amplifier AV, and then flows into the SU ports of the air control valves D3 and D4 and the SU ports of the air lock valves D1 and D2 through the amplifier AV to enter the non-shaft side and the shaft side of the cylinder, forming a protection state at this moment; 4) The passage through the E port of the air control valve D4 is terminated.

[0027] 4. Valve status: Adjustment (piston rod retraction corresponds to valve opening) In working gas source: normal, control signal: normal, YV: energized Overview: The working air source flows into the position-holding intelligent valve positioner P through the filter pressure reducing valve AFR, and is discharged into the amplifier AV through OUT1 and OUT2. Then, it flows through the SU ports of the air control valves D3 and D4 and the SU ports of the air lock valves D1 and D2 from both sides and enters the non-shaft side and the shaft side of the cylinder. At this time, the position-holding intelligent valve positioner P can be used for local or remote adjustment.

[0028] Specifically: The working gas source is divided into 4 paths through the filter pressure reducing valve AFR and enters the control system circuit: Act on the gas lock valve D so that the working gas source forms a passage through the US port on the gas lock valves D1 and D2; Acting on the solenoid valve YV, at this time, after the solenoid valve YV is energized to form a passage at port 31, the gas source flows out and acts on the gas control valves D3 and D4 to form a passage at their ports SU; Acting on the position-holding intelligent valve positioner P, the exhaust gas from OUT1 and OUT2 flows into the amplifier AV, and then flows into the SU ports of the air control valves D3 and D4 and the SU ports of the air lock valves D1 and D2 through the amplifier AV to enter the non-shaft side and the shaft side of the cylinder. At this moment, a complete air control circuit is formed. The position-holding intelligent valve positioner P can be used to realize local and remote control and adjustment of the cylinder.

Claims

1. A high and low bypass fault-protection multifunctional pneumatic actuator control system, characterized in that: The air source is connected to the filter pressure reducing valve (AFR) and the oil mist separator (AM) through the main pipeline. The main pipeline is divided into the first, second and third branches. The first branch is connected to the air inlet end of the intelligent valve positioner (P). The first branch is connected to the air inlet pipeline and the air outlet pipeline are respectively connected to the air inlet end and the air outlet end of the pneumatic actuator through pipelines. The air inlet pipeline is connected in series with the air lock valve (D1), the air control valve (D3) and the first flow amplifier (AV1). The air outlet pipeline is connected in series with the air lock valve (D2), the air control valve ( The first flow amplifier (AV1) and the second flow amplifier (AV2) are respectively connected to the connecting pipeline of the intelligent valve positioner (P); the second branch is connected to the air lock valve (D), and the air lock valve (D) is respectively connected to the air lock valve (D1) and (D2); the third branch is connected to the solenoid valve (YV), and the control end of the solenoid valve (YV) is respectively connected to the control end of the air control valve (D3) and (D4), and the exhaust port of the air control valve (D4) is connected to the third branch.

2. The high and low bypass fault-proof multifunctional pneumatic actuator control system according to claim 1 is characterized in that: The intelligent valve positioner (P) receives a control signal from the DCS, so that the OUT1 and OUT2 sides of the intelligent valve positioner (P) discharge or exhaust gas, and controls the pneumatic actuator to extend or retract the piston rod through the connecting pipeline, the air lock valve (D), the air lock valves (D1), (D2), and the air control valves (D3), (D4).

3. The high and low bypass fault-proof multifunctional pneumatic actuator control system according to claim 1 is characterized in that: The intelligent valve positioner (P) is directly mounted on the pneumatic actuator, which is convenient for on-site operation and assembly.

4. The high and low bypass fault-protection multifunctional pneumatic actuator control system according to claim 1 is characterized in that: The intelligent valve positioner (P) is a position-holding type intelligent valve positioner, and the pneumatic actuator is a double-acting cylinder (A).

5. The control method of the high and low bypass fault-proof multifunctional pneumatic actuator control system according to claim 1 is characterized in that: S1: Valve status: hold position, piston rod retracts and valve opens In working gas source: loss of gas, control signal: arbitrary, YV: arbitrary; When there is no working gas source, each control element in the system is in the initial state, no gas flows into the cylinder, and the cylinder is in a position-holding state; S2: Valve status: open valve, the piston rod retracts and the valve is open; In working gas source: normal, control signal: arbitrary, YV: power off The working gas source flows through the filter pressure reducing valve AFR, through the air control valve D4 to the air lock valve D2 and enters the cylinder on the shaft side. The gas in the cylinder on the non-shaft side flows through the air lock valve D1 to the air control valve D3 muffler and is discharged; S3: Valve status: holding position, the piston rod retracts and the valve is opened; In working gas source: normal, control signal: lost signal, YV: energized; The working gas source flows into the amplifier AV through the filter pressure reducing valve AFR, and then flows through the gas control valves D3, D4 and the gas lock valves D1, D2 from both sides to enter the non-shaft side and the shaft side of the cylinder, at this moment, the position retention state is formed; S4: Valve status: adjustment, piston rod retraction corresponds to valve opening; In working gas source: normal, control signal: normal, YV: energized; The working air source flows into the position-holding intelligent valve positioner P through the filter pressure reducing valve AFR, and is discharged into the amplifier AV through OUT1 and OUT2. Then, it flows through the SU ports of the air control valves D3 and D4 and the SU ports of the air lock valves D1 and D2 from both sides and enters the non-shaft side and the shaft side of the cylinder. At this time, the position-holding intelligent valve positioner P can be used for local or remote adjustment.

6. The control method according to claim 5, characterized in that: The specific steps of S2 are: The working gas source is divided into 4 paths through the filter pressure reducing valve AFR and enters the control system circuit: Act on the gas lock valve D so that the working gas source forms a passage through the US port on the gas lock valves D1 and D2; Acting on the solenoid valve YV passage port passage termination; Acting on the position-holding intelligent valve positioner P, it flows into the amplifier AV through OUT1 and OUT2, and the passage in the S port of the air control valve D3 and D4 through the amplifier AV is closed; The gas flows through the EU port of the air control valve D4 to the SU port of the air lock valve D2 and enters the cylinder on the shaft side. The gas in the cylinder on the non-shaft side is discharged through the US port of the air lock valve D1 to the muffler of the UE port of the air control valve D3.

7. The control method according to claim 5, characterized in that: The specific steps of S3 are: Specifically: The working gas source is divided into 4 paths through the filter pressure reducing valve AFR and enters the control system circuit: Act on the gas lock valve D so that the working gas source forms a passage through the US port on the gas lock valves D1 and D2; Acting on the solenoid valve YV, at this time, after the solenoid valve YV is energized to form a passage at port 31, the gas source flows out and acts on the gas control valves D3 and D4 to form a passage at their ports SU; 3) It acts on the position-holding intelligent valve positioner P, but at this moment it is in the signal-losing state, and OUT1 and OUT2 are not exhausted. The working gas source flows directly into the amplifier AV, and then flows into the SU ports of the air control valves D3 and D4 and the SU ports of the air lock valves D1 and D2 through the amplifier AV to enter the non-shaft side and the shaft side of the cylinder, forming a protection state at this moment; 4) The passage through the E port of the air control valve D4 is terminated.

8. The control method according to claim 5, characterized in that: The specific steps of S4 are: The working gas source is divided into 4 paths through the filter pressure reducing valve AFR and enters the control system circuit; Act on the gas lock valve D so that the working gas source forms a passage through the US port on the gas lock valves D1 and D2; Acting on the solenoid valve YV, at this time, after the solenoid valve YV is energized to form a passage at port 31, the gas source flows out and acts on the gas control valves D3 and D4 to form a passage at their ports SU; Acting on the position-holding intelligent valve positioner P, the exhaust gas from OUT1 and OUT2 flows into the amplifier AV, and then flows into the SU ports of the air control valves D3 and D4 and the SU ports of the air lock valves D1 and D2 through the amplifier AV to enter the non-shaft side and the shaft side of the cylinder. At this moment, a complete air control circuit is formed. The position-holding intelligent valve positioner P can be used to realize local and remote control and adjustment of the cylinder.

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