CN101793276A - Electrohydraulic servo system for two-way high-speed switch - Google Patents
Electrohydraulic servo system for two-way high-speed switch Download PDFInfo
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- CN101793276A CN101793276A CN201019063045A CN201019063045A CN101793276A CN 101793276 A CN101793276 A CN 101793276A CN 201019063045 A CN201019063045 A CN 201019063045A CN 201019063045 A CN201019063045 A CN 201019063045A CN 101793276 A CN101793276 A CN 101793276A
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Abstract
The invention relates to an electrohydraulic servo system for a two-way high-speed switch, and relates to the technical field of valve control. The electrohydraulic servo system solves the technical problem that in the prior art, the control precision and the response speed cannot be ensured simultaneously. The system comprises execution loop, a high-speed control loop and an oil box, wherein the execution loop comprises a servo motor, a two-way pump, an oil cylinder, two lock valves and two prefill valves, and is used for performing low-speed and accurate control on a turbine valve; and the high-speed control loop comprises a rapid cut-off solenoid valve, a storage pump motor, a storage pump, a high-voltage energy accumulator and two high-speed oil-taking check valves, and is used for controlling the high-speed opening and high-speed closing actions of the turbine valve. The electrohydraulic servo system has the advantages of high response speed, high control accuracy and low running cost.
Description
Technical field
The present invention relates to the technology of valve control, particularly relate to a kind of technology of electrohydraulic servo system of two-way snap switch.
Background technique
Hydraulic servo-actuator (oil engine) is the power unit of Steam Turhine Adjustment and security system, it also is the power unit of various industrial control valves, its major function is to change its piston action of control in real time by hydraulic pressure, and then the aperture of control (steam turbine) valve.
Traditional steam turbine control system all adopts the electrohydraulic servo system of valve control oil engine, this system (referring to Fig. 2) adopts the electrohydraulic control Hs by outside fuel feeding, the filler opening of electrohydraulic control Hs is connected outside oil sources respectively with return opening, and two control ports connect two active chambers of piston type oil engine U2 respectively; Transfer valve bit instruction signal during operation, the valve position feedback signal LVDT of oil engine U2 after transferring electrical signal to, demodulator TD is compared with valve position command signal C, and according to comparative result control electrohydraulic control Hs action, and then the piston stroke of control oil engine U2.Because electrohydraulic control has speed of response faster, therefore this system can satisfy the requirement of the regulating system of feed pump turbine to quick response well.But because the intrinsic structural feature of electrohydraulic control itself, make this system have following shortcoming: 1) requirement on machining accuracy of electrohydraulic control is higher, and its price is very expensive; 2) because the electro-hydraulic servo valve arrangement is tiny and valve body is fragile, therefore responsive especially to oil contamination, its spool is caused malfunctioning easily by the wearing and tearing of the impurity in the fluid, therefore must be equipped with the very high filtration system of filter precision; 3) because electrohydraulic control is responsive to temperature variation, and the energy loss of valve control oil engine electrohydraulic servo system is very serious, and its throttling heating is bigger, therefore must be equipped with more perfect cooling system; 4), thereby the volume and the complexity of entire system have been increased because electrohydraulic control by outside fuel feeding, therefore needs a cover pumping station system that constant pressure oil source is provided; 5) be in inoperative during the cycle (pressurize operating mode and idle running operating mode) when system, system still locates running state, has increased operating cost.Above-mentioned shortcoming makes that the cost of valve control oil engine electrohydraulic servo system is higher.
In order to overcome the shortcoming of valve control oil engine electrohydraulic servo system, a kind of directly driven volume controlled electro-hydraulic servo system (DDVC system) has appearred, the hydraulic main circuit of this system (referring to Fig. 3) adopts closed oil circuit, two hydraulic fluid ports of its oil pump D3 connect two active chambers of piston type oil engine U3 respectively, also are provided with Fill valve (two Pilot operated check valve H31, H32) that is used for balance sysmte oil mass difference in volume of positive and negative when operation and the locking-valve (two Pilot operated check valve H33, H34) that is used to pin piston rod in system; Control the output flow of oil pump D3 and the flow direction of hydraulic oil by AC servo motor M3 during operation, and then the piston stroke of control oil engine U3.This system has the following advantages: 1) because hydraulic main circuit is a closed circuit, therefore system with oil mass seldom and be subjected to the outside contamination chance less only needs little fuel tank (oil tank) get final product, and does not have sensing element in the system, so also do not need to be equipped with filtrating equipment; 2) owing to do not have throttle element in the directly driven volume controlled electro-hydraulic servo system, pressure loss is very little, so the heat that oil pump when work produces seldom, and system can not need to be equipped with cooling system from heat radiation; When 3) system only work in actuator, just start AC servo motor, when system is in inoperative (the pressurize operating mode and the operating mode that dallies) consumed energy hardly during the cycle, its operating cost is very low.Therefore directly driven volume controlled electro-hydraulic servo system relative valve control oil engine electrohydraulic servo system cost is lower, but because the sensitivity of AC servo motor and oil pump combination will be lower than the sensitivity of electrohydraulic control, therefore the speed of response of this system is slower, can't be applied to the large steam turbine that quick closedown and quick opening function are had relatively high expectations.
Summary of the invention
At the defective that exists in the above-mentioned prior art, technical problem to be solved by this invention provide a kind of speed of response fast, the control accuracy height, the electrohydraulic servo system of the two-way snap switch that operating cost is low.
In order to solve the problems of the technologies described above, the electrohydraulic servo system of a kind of two-way snap switch provided by the present invention comprises and carries out loop and fuel tank; Described execution loop comprises actuating motor, two-way pump, oil cylinder, two locking-valves and two Fill valves; Described actuating motor connects and the operation of control two-way pump; Described oil cylinder has two active chambers, and one of them active chamber is a rod chamber, and another active chamber is a rodless cavity; Described two-way pump has two hydraulic fluid ports, is respectively first hydraulic fluid port and second hydraulic fluid port;
Described two locking-valves are respectively first locking-valve and second locking-valve; First hydraulic fluid port of described two-way pump is through the rodless cavity of first locking-valve connection oil cylinder, and its second hydraulic fluid port connects the rod chamber of oil cylinder through second locking-valve;
Described two Fill valves are respectively first Fill valve and second Fill valve; Described fuel tank connects second hydraulic fluid port of two-way pump through first hydraulic fluid port of first Fill valve connection two-way pump through second Fill valve;
Described locking-valve and Fill valve are Pilot operated check valve, and wherein the control port of first locking-valve and first Fill valve is connected second hydraulic fluid port of two-way pump, and the control port of second locking-valve and second Fill valve is connected first hydraulic fluid port of two-way pump;
Be provided with liquid level sensor in the described oil cylinder, described liquid level sensor connects and the operation of control actuating motor through a demodulator, a servoamplifier;
It is characterized in that: also wrap the quick control loop; Described quick control loop comprises quick closing valve solenoid valve, storage pump motor, storage pump, high pressure accumulator, the first quick oil feeding one-way valve and the second quick oil feeding one-way valve;
Described quick closing valve solenoid valve has a filler opening, a return opening and two actuator ports, wherein two actuator ports are respectively first actuator port and second actuator port, its first actuator port connects the rod chamber of oil cylinder through the first quick oil feeding one-way valve, second actuator port connects the rodless cavity of oil cylinder through the second quick oil feeding one-way valve, its return opening connects fuel tank, its filler opening connects fuel tank through a relief valve, and is connected to a upward pressure switch and a downforce switch; Described upward pressure switch is connected with the downforce switch and controls the operation of storage pump motor, is respectively applied for closing and opening of control storage pump motor;
Described first, second quick oil feeding one-way valve is Pilot operated check valve, wherein the control port of the first quick oil feeding one-way valve connects second actuator port of quick closing valve solenoid valve, and the control port of the second quick oil feeding one-way valve connects first actuator port of quick closing valve solenoid valve;
Described storage pump motor connects and the operation of control storage pump, the filler opening of described storage pump is often opened the oil suction stop valve through one and is connected fuel tank, and being provided with a normally closed oil cut-off valve that adds that is used to connect outside oil sources, its oil outlet is connected to the filler opening of quick closing valve solenoid valve successively through an one-way valve, a filter;
Described high pressure accumulator is connected to fuel tank through the stop valve of draining the oil, and connects the filler opening of quick closing valve solenoid valve through an oil-feed stop valve.
Further, described fuel tank is provided with a filler opening, and its filler opening connects outside oil sources through a prepressing type air-strainer.
The electrohydraulic servo system of two-way snap switch provided by the invention, by actuating motor and two-way pump steam turbine valve being carried out low speed accurately controls, by high pressure accumulator, quick closing valve solenoid valve steam turbine valve is opened action control with quick closedown fast, its control accuracy height, speed of response is fast; And since oil cylinder directly drive by actuating motor, compare with the hydraulic actuator of servovalve driving oil cylinder, its effective working pressure has improved 1/3rd, also be same size oil cylinder push-pull effort big 1/3rd; Requirement to hydraulic system hydraulic pressure turbidity test also can be reduced to the NAS8 level from the NAS5 level of servo valve control system, greatly reduces the cost of system's operation maintenance, has improved reliability of system operation.
Description of drawings
Fig. 1 is the hydraulic diagram of electrohydraulic servo system of the two-way snap switch of the embodiment of the invention;
Fig. 2 is the hydraulic diagram of the electrohydraulic servo system of existing valve control oil engine;
Fig. 3 is the hydraulic diagram of existing directly driven volume controlled electro-hydraulic servo system.
Embodiment
Below in conjunction with description of drawings embodiments of the invention are described in further detail, but present embodiment is not limited to the present invention, every employing analog structure of the present invention and similar variation thereof all should be listed protection scope of the present invention in.
As shown in Figure 1, the electrohydraulic servo system of a kind of two-way snap switch that the embodiment of the invention provided comprises and carries out loop and fuel tank N2; Described execution loop comprises actuating motor SM1, two-way pump PM2, oil cylinder CY1, two locking-valves and two Fill valves; Described actuating motor SM1 connects and control two-way pump PM2 operation; Described oil cylinder CY1 has two active chambers, and one of them active chamber is a rod chamber, and another active chamber is a rodless cavity; Described two-way pump PM2 has two hydraulic fluid ports, is respectively first hydraulic fluid port and second hydraulic fluid port;
Described two locking-valves are respectively the first locking-valve R3 and the second locking-valve R4; First hydraulic fluid port of described two-way pump PM2 is through the rodless cavity of first locking-valve R3 connection oil cylinder CY1, and its second hydraulic fluid port connects the rod chamber of oil cylinder CY1 through the second locking-valve R4;
Described two Fill valves are respectively the first Fill valve R5 and the second Fill valve R6; Described fuel tank N2 connects second hydraulic fluid port of two-way pump PM2 through first hydraulic fluid port of first Fill valve R5 connection two-way pump PM2 through the second Fill valve R6;
Described locking-valve and Fill valve are Pilot operated check valve, and wherein the control port of the first locking-valve R3 and the first Fill valve R5 is connected second hydraulic fluid port of two-way pump PM2, and the control port of the second locking-valve R4 and the second Fill valve R6 is connected first hydraulic fluid port of two-way pump PM2;
Be provided with the liquid level sensor (not shown) in the described oil cylinder CY1, described liquid level sensor connects and control actuating motor SM1 operation through a demodulator TD, a servoamplifier S;
It is characterized in that: also wrap the quick control loop; Described quick control loop comprises quick closing valve solenoid valve F, storage pump motor EM1, storage pump PM1, high pressure accumulator N1, the first quick oil feeding one-way valve R1 and the second quick oil feeding one-way valve R2;
Described quick closing valve solenoid valve F has a filler opening, a return opening and two actuator ports, wherein two actuator ports are respectively first actuator port and second actuator port, its first actuator port connects the rod chamber of oil cylinder CY1 through the first quick oil feeding one-way valve R1, second actuator port connects the rodless cavity of oil cylinder CY1 through the second quick oil feeding one-way valve R2, its return opening connects fuel tank N2, its filler opening connects fuel tank N2 through a relief valve RF, and is connected to a upward pressure switch P S1 and a downforce switch P S2; Described upward pressure switch P S1 is connected with downforce switch P S2 and controls storage pump motor EM1 operation, is respectively applied for closing and opening of control storage pump motor EM1;
Described first, second quick oil feeding one-way valve is Pilot operated check valve, wherein the control port of the first quick oil feeding one-way valve R1 connects second actuator port of quick closing valve solenoid valve F, and the control port of the second quick oil feeding one-way valve R2 connects first actuator port of quick closing valve solenoid valve F;
Described storage pump motor EM1 connects and control storage pump PM1 operation, the filler opening of described storage pump PM1 is often opened oil suction stop valve SH7 through one and is connected fuel tank N2, and being provided with a normally closed oil cut-off valve SH8 that adds that is used to connect outside oil sources, its oil outlet is connected to the filler opening of quick closing valve solenoid valve F successively through an one-way valve R0, a filter F L;
Described high pressure accumulator N1 is connected to fuel tank N2 through the stop valve SH2 that drains the oil, and connects the filler opening of quick closing valve solenoid valve F through an oil-feed stop valve SH1;
In the embodiment of the invention, described fuel tank N2 is provided with a filler opening, and its filler opening connects outside oil sources through a prepressing type air-strainer Y; The rodless cavity of described oil cylinder CY1 is connected to an oil cylinder working-pressure sensor I2, and its rod chamber is connected to an oil cylinder working-pressure sensor I1; Described fuel tank N2 is connected to a reservoir pressure table M2 and a reservoir pressure sensor I0; The filler opening of described quick closing valve solenoid valve F is connected to a high-pressure manometer M1;
The embodiment of the invention also is provided with an oil storage pressure tap PT4 and a high pressure pressure tap PT5, and described oil storage pressure tap PT4 connects fuel tank N2 through an one-way valve, and described high pressure pressure tap PT5 connects the filler opening of quick closing valve solenoid valve F through an one-way valve;
During embodiment of the invention control steam turbine valve, with the servoamplifier S in the valve position signal C access execution loop of steam turbine valve;
Under normal state, the filler opening of quick closing valve solenoid valve F and the oil circuit of two actuator ports turn-off, steam turbine valve carried out low speed by actuating motor SM1 according to the feedback signal of the valve position control signal C of steam turbine valve and the liquid level sensor in the oil cylinder CY1 and accurately controlled this moment, when the valve position control signal C that detects steam turbine valve as servoamplifier S changes, after the feedback signal that is about to itself and liquid level sensor compares changing value is delivered to actuating motor SM1, actuating motor SM1 is according to above-mentioned changing value control two-way pump PM2 forward or reverse, and then the piston rod of control oil cylinder CY1 stretches out or withdraw, makes the piston rod drive steam turbine valve of oil cylinder CY1 make corresponding action;
When steam turbine valve need be opened fast, the filler opening of quick closing valve solenoid valve F is communicated with first actuator port, its second actuator port is communicated with its return opening, high pressure oil among the high pressure accumulator N1 is through first actuator port of quick closing valve solenoid valve F at this moment, the first quick oil feeding one-way valve R1 is loaded in the rod chamber of oil cylinder CY1 fast, hydraulic oil in the rodless cavity of oil cylinder CY1 is by the second quick oil feeding one-way valve R2, second actuator port of quick closing valve solenoid valve F is back to fuel tank N2 fast, make the piston rod fast retractile of oil cylinder, thereby the valve that drives steam turbine is opened fast;
When steam turbine valve needs quick closedown, the filler opening of quick closing valve solenoid valve F is communicated with second actuator port, its first actuator port is communicated with its return opening, high pressure oil among the high pressure accumulator N1 is through second actuator port of quick closing valve solenoid valve F at this moment, the second quick oil feeding one-way valve R2 is loaded in the rodless cavity of oil cylinder CY1 fast, hydraulic oil in the rod chamber of oil cylinder CY1 is by the first quick oil feeding one-way valve R1, first actuator port of quick closing valve solenoid valve F is back to fuel tank N2 fast, make the piston rod of oil cylinder stretch out fast, thereby drive the valve quick closedown of steam turbine;
When pressure switch PS2 detects pressure in the quick control loop and is lower than minimum setting value instantly, promptly send actuating signal to storage pump motor EM1, storage pump motor EM1 receives that promptly to control storage pump PM1 after the actuating signal oil-filled to the quick control loop; When upward pressure switch P S1 detects pressure in the quick control loop and is higher than the highest setting value, promptly send stop signal to storage pump motor EM1, storage pump motor EM1 receives that promptly controlling storage pump PM1 after the stop signal stops oil-filled; When the pressure in the quick control loop surpassed the highest setting value, pressure was by relief valve RF overflow, thereby provided overvoltage protection for system; When system need replenish hydraulic oil, earlier outside oil sources is connected to the normally closed oil cut-off valve SH8 that adds of storage pump PM1 filler opening, open this normally closed oil cut-off valve SH8 that adds then and can replenish hydraulic oil.
Claims (2)
1. the electrohydraulic servo system of a two-way snap switch comprises and carries out loop and fuel tank; Described execution loop comprises actuating motor, two-way pump, oil cylinder, two locking-valves and two Fill valves; Described actuating motor connects and the operation of control two-way pump; Described oil cylinder has two active chambers, and one of them active chamber is a rod chamber, and another active chamber is a rodless cavity; Described two-way pump has two hydraulic fluid ports, is respectively first hydraulic fluid port and second hydraulic fluid port;
Described two locking-valves are respectively first locking-valve and second locking-valve; First hydraulic fluid port of described two-way pump is through the rodless cavity of first locking-valve connection oil cylinder, and its second hydraulic fluid port connects the rod chamber of oil cylinder through second locking-valve;
Described two Fill valves are respectively first Fill valve and second Fill valve; Described fuel tank connects second hydraulic fluid port of two-way pump through first hydraulic fluid port of first Fill valve connection two-way pump through second Fill valve;
Described locking-valve and Fill valve are Pilot operated check valve, and wherein the control port of first locking-valve and first Fill valve is connected second hydraulic fluid port of two-way pump, and the control port of second locking-valve and second Fill valve is connected first hydraulic fluid port of two-way pump;
Be provided with liquid level sensor in the described oil cylinder, described liquid level sensor connects and the operation of control actuating motor through a demodulator, a servoamplifier;
It is characterized in that: also wrap the quick control loop; Described quick control loop comprises quick closing valve solenoid valve, storage pump motor, storage pump, high pressure accumulator, the first quick oil feeding one-way valve and the second quick oil feeding one-way valve;
Described quick closing valve solenoid valve has a filler opening, a return opening and two actuator ports, wherein two actuator ports are respectively first actuator port and second actuator port, its first actuator port connects the rod chamber of oil cylinder through the first quick oil feeding one-way valve, second actuator port connects the rodless cavity of oil cylinder through the second quick oil feeding one-way valve, its return opening connects fuel tank, its filler opening connects fuel tank through a relief valve, and is connected to a upward pressure switch and a downforce switch; Described upward pressure switch is connected with the downforce switch and controls the operation of storage pump motor, is respectively applied for closing and opening of control storage pump motor;
Described first, second quick oil feeding one-way valve is Pilot operated check valve, wherein the control port of the first quick oil feeding one-way valve connects second actuator port of quick closing valve solenoid valve, and the control port of the second quick oil feeding one-way valve connects first actuator port of quick closing valve solenoid valve;
Described storage pump motor connects and the operation of control storage pump, the filler opening of described storage pump is often opened the oil suction stop valve through one and is connected fuel tank, and being provided with a normally closed oil cut-off valve that adds that is used to connect outside oil sources, its oil outlet is connected to the filler opening of quick closing valve solenoid valve successively through an one-way valve, a filter;
Described high pressure accumulator is connected to fuel tank through the stop valve of draining the oil, and connects the filler opening of quick closing valve solenoid valve through an oil-feed stop valve.
2. the electrohydraulic servo system of two-way snap switch according to claim 1, it is characterized in that: described fuel tank is provided with a filler opening, and its filler opening connects outside oil sources through a prepressing type air-strainer.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201019063045A CN101793276A (en) | 2010-02-08 | 2010-02-08 | Electrohydraulic servo system for two-way high-speed switch |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201019063045A CN101793276A (en) | 2010-02-08 | 2010-02-08 | Electrohydraulic servo system for two-way high-speed switch |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102996887A (en) * | 2011-09-14 | 2013-03-27 | 中国海洋石油总公司 | High-reliability valve control loop |
| CN103307060A (en) * | 2013-06-18 | 2013-09-18 | 南京埃尔法电液技术有限公司 | Direct drive type servo pump control electro-hydraulic combined driving hydraulic cylinder control system and control method |
| CN108215108A (en) * | 2016-12-15 | 2018-06-29 | 群达模具(深圳)有限公司 | A kind of quick response servo-control system of injection moulding machine |
| CN111550458A (en) * | 2020-04-27 | 2020-08-18 | 杭州澎康自动化科技有限公司 | Steam turbine pump cylinder control servo system and control method thereof |
-
2010
- 2010-02-08 CN CN201019063045A patent/CN101793276A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102996887A (en) * | 2011-09-14 | 2013-03-27 | 中国海洋石油总公司 | High-reliability valve control loop |
| CN102996887B (en) * | 2011-09-14 | 2015-02-18 | 中国海洋石油总公司 | High-reliability valve control loop |
| CN103307060A (en) * | 2013-06-18 | 2013-09-18 | 南京埃尔法电液技术有限公司 | Direct drive type servo pump control electro-hydraulic combined driving hydraulic cylinder control system and control method |
| CN103307060B (en) * | 2013-06-18 | 2016-02-03 | 南京埃斯顿自动化股份有限公司 | The oil hydraulic cylinder control system of directly driving type servo-pump control electricity liquid combination drive and controlling method |
| CN108215108A (en) * | 2016-12-15 | 2018-06-29 | 群达模具(深圳)有限公司 | A kind of quick response servo-control system of injection moulding machine |
| CN108215108B (en) * | 2016-12-15 | 2024-02-27 | 深圳市中科晟达互联智能科技有限公司 | Quick response servo control system of injection molding machine |
| CN111550458A (en) * | 2020-04-27 | 2020-08-18 | 杭州澎康自动化科技有限公司 | Steam turbine pump cylinder control servo system and control method thereof |
| CN111550458B (en) * | 2020-04-27 | 2022-04-26 | 杭州澎康自动化科技有限公司 | Steam turbine pump cylinder control servo system and control method thereof |
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Application publication date: 20100804 |