Solenoid valve two-out-of-four pressure detection assembly for steam turbine speed regulation security system and use method of solenoid valve two-out-of-four pressure detection assembly

Abstract

The invention aims to provide an electromagnetic valve two-out-of-four pressure detection assembly for a steam turbine speed regulation security system and a use method, and relates to the technical field of steam turbines. When more than two of four shutdown electromagnetic valves are powered off at the same time, corresponding pilot cartridge valve control cavities are opened due to pressure loss; therefore, the pressure of the pressure detection oil circuit is quickly relieved through the oil return port of the shutdown electromagnetic valve which loses power. And when the pressure of the pressure detection oil way is reduced to about 0.35 MPa or below, the oil return cartridge valve is opened under the action of a spring in the oil return cartridge valve, and the quick-closing oil way and the oil return oil way are communicated for pressure relief, so that the quick-closing valve is triggered to be quickly closed, and emergency shutdown protection is realized. Overall false shutdown cannot be caused by single-point or double-point faults of two-out-of-four faults, the overall stable operation performance is greatly improved, and overall shutdown can be caused only when more serious multiple faults occur.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of steam turbines, in particular to a four-to-two pressure detection assembly for a steam turbine speed regulating and security system and a use method thereof. BACKGROUND

[0002] With the continuous promotion of predictive and health management technology in the fields of electric power and chemical industry, the reliability and safety of steam turbine control systems have become critical. In the operation of steam turbines, the hydraulic security system, as a core protection device, is used to monitor abnormal parameters and trigger emergency shutdown to prevent equipment damage. The health status of elements such as electromagnetic valves and pressure detection components directly affects the response speed and fault tolerance ability of the system, and the demand for multi-source data fusion and intelligent diagnosis is increasingly prominent.

[0003] For example, the patent for invention with publication number CN114320495A discloses an EH oil filter screen clogging early warning system for a steam turbine EH oil system. The system monitors parameters such as EH oil tank level, mother pipe oil pressure, and oil pump current in real time, and combines a subtracter, an absolute value module, and a logic judgment module to achieve early warning of filter screen clogging. This method can identify oil pressure fluctuations and current jumps, but it focuses on the health monitoring of a single oil line system and lacks comprehensive diagnosis of the overall pressure state of the security system, and does not involve dynamic pressure interaction analysis of the electromagnetic valve group.

[0004] For another example, the utility model patent with publication number CN209704650U discloses a steam turbine security system emergency protection device, which adopts modular design, integrates multiple shutdown electromagnetic valves, pressure gauges, and cartridge valves, improves system safety through four-to-two logic, and reduces pipeline leakage points. The device allows for on-site or online monitoring of pressure, but mainly relies on hardware redundancy and threshold judgment, does not introduce multi-source data trend fusion analysis, and is difficult to achieve early prediction and adaptive intervention of faults.

[0005] Currently, steam turbine security systems mostly use protection strategies based on single-point pressure thresholds, which are easily affected by measurement point drift, false positives, or operating condition fluctuations. When a fault occurs, it can lead to overall shutdown for maintenance. Moreover, existing systems lack dynamic prediction of electromagnetic valve group pressure, making maintenance of the electromagnetic valve group more difficult.

[0006] In view of the above problems, there is an urgent need to develop a four-to-two pressure detection assembly for a steam turbine speed regulating and security system and a use method thereof. SUMMARY

[0007] Technical problems solved In view of the deficiencies of the prior art, the present application provides a solenoid valve four-to-two pressure detection assembly for a steam turbine speed regulation security system and a use method, which solves the problem that the steam turbine security system is prone to be affected by measurement point drift, false alarms or working condition fluctuations when a single-point pressure threshold-based protection strategy is used, and the whole system is shut down for maintenance when a fault occurs. Moreover, the existing system lacks dynamic prediction of solenoid valve group pressure, resulting in increased difficulty in maintaining the solenoid valve group.

[0008] Technical scheme To achieve the above object, the present application is implemented by the following technical scheme: a solenoid valve four-to-two pressure detection assembly for a steam turbine speed regulation security system, comprising: an oil way switching valve, four shutdown solenoid valves, four stop valves, an oil way stop valve fixed on a detection main body; four pilot plug-in valves, an oil way plug-in valve, a quick closing plug-in valve, two oil return plug-in valves, a quick closing solenoid valve, a starting solenoid valve, a quick closing test valve and a manual shutdown valve, a starting oil way, a pressure oil way, a quick closing oil way, an oil return oil way, a pressure detection oil way and a test oil way are arranged in the detection main body, one stop valve is connected in series at the front end of the oil inlet of each of the four shutdown solenoid valves; the control cavities of one pilot plug-in valve are connected to the oil outlets of one of the four shutdown solenoid valves at the rear end; the oil inlets of two shutdown solenoid valves are connected in series to form a group, the oil inlets of two shutdown solenoid valves are connected in series to form another group, and the two groups are connected in parallel to the pressure oil way; the oil outlets of the four pilot plug-in valves are connected in parallel to the pressure detection oil way; the pressure detection oil way is connected to the control cavities of two parallel oil return plug-in valves; the oil inlets of the two oil return plug-in valves are communicated with the quick closing oil way, and the oil outlets are communicated with the oil return oil way; when all the four shutdown solenoid valves are powered, the pressure detection oil way is pressurized by the pilot plug-in valve, the two oil return plug-in valves are closed, and the quick closing oil way is pressurized; when two different groups of shutdown solenoid valves lose power at the same time: two shutdown solenoid valves, two shutdown solenoid valves, two shutdown solenoid valves or two shutdown solenoid valves lose power at the same time, the pressure detection oil way is depressurized, the two oil return plug-in valves are opened, and the quick closing oil way is depressurized; when two same groups of shutdown solenoid valves lose power at the same time: two shutdown solenoid valves or two shutdown solenoid valves lose power at the same time, the quick closing oil way is not depressurized.

[0009] Further, the manual shutdown valve is connected to the pressure oil way; the oil way switching valve, the quick closing solenoid valve, the starting solenoid valve, the quick closing test valve, the manual shutdown valve and the oil return outlets of the four shutdown solenoid valves are connected in parallel to the oil return oil way.

[0010] Further, the oil way stop valve is fixedly connected between the pressure detection oil way and the control cavities of the two oil return plug-in valves.

[0011] Further, the quick closing valve driving circuit further comprises an oil passage plug-in valve in the oil passage switching valve, wherein the oil passage plug-in valve is controlled by a starting electromagnetic valve to open and close, and is used to guide the pressure oil of the starting oil passage to be on or off; an oil inlet of the quick closing plug-in valve is connected to a pressure oil passage, and an oil outlet is connected to a quick closing oil passage; a control cavity of the quick closing plug-in valve is controlled by a quick closing electromagnetic valve, and an outlet of the quick closing electromagnetic valve is connected to the control cavity of the quick closing plug-in valve; wherein when the quick closing electromagnetic valve is powered, the quick closing plug-in valve is driven to close the oil passage plug-in valve; and when the quick closing electromagnetic valve is powered off, the quick closing plug-in valve is opened.

[0012] Further, the oil return port of the starting electromagnetic valve is provided with a throttling device.

[0013] Further, two electromagnetic switches are connected in parallel after the pressure oil passage is connected with the switching valve.

[0014] A use method is applied to a four-to-two pressure detection assembly of a turbine speed regulation and safety system electromagnetic valve, and the use method comprises the following steps: S1: confirming that the four stop electromagnetic valves are powered, monitoring that the pressure of the pressure detection oil passage is 0.8-1.1 MPa, and keeping the pressure of the quick closing oil passage; S2: powering the starting electromagnetic valve and the quick closing electromagnetic valve at the same time, powering the starting electromagnetic valve to drive the oil passage plug-in valve to be opened to establish the starting oil passage, and powering the quick closing electromagnetic valve to drive the quick closing plug-in valve and the oil passage plug-in valve to cut off the passage of the pressure oil to the quick closing oil passage; S3: after a first delay, powering off the quick closing electromagnetic valve to establish the quick closing oil passage; S4: after a second delay, powering off the starting electromagnetic valve, releasing the pressure of the starting oil passage through throttling, and slowly opening the quick closing valve.

[0015] Further, the method further comprises an emergency stop step: when any one of the two stop electromagnetic valves, the two stop electromagnetic valves, the two stop electromagnetic valves or the two stop electromagnetic valves is powered off at the same time, or when the manual stop valve is operated, the pressure of the pressure detection oil passage is released to be lower than 0.35 MPa, the oil return plug-in valve is opened, the pressure of the quick closing oil passage is released, and the quick closing valve is quickly closed.

[0016] Further, the method further comprises an online test step: the quick closing test valve is powered to guide the pressure oil into the test oil passage to partially offset the pressure of the quick closing oil passage, the quick closing test valve is partially displaced for testing, and the quick closing test valve will not be completely closed.

[0017] Further, the method further comprises an online replacement of the stop electromagnetic valve step: the corresponding stop valve is closed before the oil inlet of the electromagnetic valve to be replaced, and the oil passage stop valve is closed, so that the stop electromagnetic valve can be disassembled and assembled online, and the four-to-two protection function of the system is maintained by the remaining normal stop electromagnetic valves.

[0018] Advantages The present application has the following advantages: (1) When the four stop electromagnetic valves are normally powered, the pressure oil enters the pressure detection oil circuit through the pilot cartridge valve, so that the pressure is established and maintained at 0.8-1.1 MPa. This pressure acts on the control cavity of the return oil cartridge valve to overcome the spring force and close it, thereby blocking the discharge channel of the quick closing oil circuit to the return oil circuit, ensuring oil pressure and the system in a ready-to-run state. When two or more of the four stop electromagnetic valves lose power at the same time, the corresponding pilot cartridge valve control cavity will lose pressure and open, causing the pressure detection oil circuit to rapidly depressurize through the return port of the de-energized stop electromagnetic valve. When the pressure detection oil circuit pressure drops below about 0.35 MPa, the return oil cartridge valve opens under the action of the spring inside it, connecting the quick closing oil circuit to the return oil circuit to depressurize, thereby triggering the quick closing valve to close quickly and achieving emergency shutdown protection. "Four to two" will not cause overall misoperation in single-point or double-point failure, greatly improving the overall stability of the operation. Only when more serious multiple failures occur will the overall system shut down.

[0019] (2) The return oil circuit T ensures the coordination of the operation of each actuator. The pressure oil circuit is connected with a manual stop valve, which can shut down the entire system manually. The return ports of the oil circuit switching valve, the quick closing electromagnetic valve, the starting electromagnetic valve, the quick closing test valve, the manual stop valve, and the four stop electromagnetic valves are all connected in parallel on the common return oil circuit. This simplifies the oil circuit structure, reduces potential leakage points, and ensures that all valve components can return smoothly and unobstructed to the oil tank when in operation, avoiding the problem of delayed or failed valve operation due to excessive back pressure in the return oil circuit, and ensuring the rapidity and accuracy of the overall system response.

[0020] (3) The oil circuit stop valve added between the pressure detection oil circuit and the control cavities of the two return oil cartridge valves is a key safety and maintenance isolation point. When the system is operating normally, the oil circuit stop valve remains fully open and does not affect the control of the return oil cartridge valve by the pressure detection oil circuit. When online testing of the system is required, such as simulating pressure detection oil circuit failure, or maintenance of the return oil cartridge valve and its associated pipelines is required, the oil circuit stop valve can be closed. This isolates the pressure detection oil circuit from the actuators, allowing personnel to safely perform related tests or maintenance work without having to take the entire security system out of operation, enhancing the maintainability and online processing capacity of the system.

[0021] (4) When the quick closing electromagnetic valve is powered, the pilot pressure oil output by it acts on the control cavity of the quick closing cartridge valve, causing it to close and thereby cutting off the supply of pressure oil to the quick closing oil circuit. When the quick closing electromagnetic valve loses power, the control cavity of the quick closing cartridge valve depressurizes and opens under the action of the spring, allowing pressure oil to enter the quick closing oil circuit. This realizes electromagnetic control of the quick closing oil circuit through oil pressure control and cooperates with the starting electromagnetic valve to complete the orderly control of the quick closing valve.

[0022] (5) First, execute step S1: confirm that all four shutdown solenoid valves are energized. At this time, the pressure detection oil circuit P13 establishes a normal pressure of 0.8-1.1 MPa, the return oil cartridge valve is closed, the quick-closing oil circuit is in a pressure-holding state, and the system is allowed to start. Next, execute step S2: energize the start solenoid valve and the quick-closing solenoid valve simultaneously. After the start solenoid valve is energized, it drives the oil circuit cartridge valve to open, and the pressurized oil enters the start oil circuit, preparing the conditions for the opening of the quick-closing valve; when the quick-closing solenoid valve is energized, it drives the quick-closing cartridge valve to close, ensuring that the pressurized oil does not enter the quick-closing oil circuit. After the first delay, for example, 2-3 seconds, execute step S3: de-energize the quick-closing solenoid valve first. The de-energization of the quick-closing solenoid valve causes the quick-closing cartridge valve to open, and the pressurized oil quickly enters and establishes the pressure of the quick-closing oil circuit. After the second delay, for example, 5-10 seconds, execute step: de-energize the start solenoid valve. After the solenoid valve is de-energized, the cartridge valve in the oil circuit closes, and the oil in the starting oil circuit is slowly depressurized through the throttling device installed at its return port. As the pressure in the starting oil circuit decreases slowly, while the quick-closing oil circuit has been pressurized, the quick-closing valve opens smoothly and slowly under the action of the pressure difference on both sides, avoiding the impact of the turbine inlet valve and achieving a smooth start-up of the turbine.

[0023] As the pressure in the starting oil circuit decreases slowly, while the pressure in the quick-closing oil circuit has been built up, the quick-closing valve opens smoothly and slowly under the action of the pressure difference on both sides, avoiding the impact of the turbine inlet valve and achieving a smooth start-up of the turbine.

[0024] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0025] Figure 1 This is the overall front view of the present invention.

[0026] Figure 2 This is a left view of the entire invention.

[0027] Figure 3 This is a rear view of the entire invention.

[0028] Figure 4 This is a right view of the entire invention.

[0029] Figure 5 This is the invention Figure 4 A sectional view at point CC.

[0030] Figure 6 This is the invention Figure 3 A cross-sectional view at BB.

[0031] Figure 7 This is the invention Figure 3 A cross-sectional view at point AA.

[0032] Figure 8 This is a diagram of the overall adjustment system of the present invention.

[0033] Figure 9 This is a diagram of the overall adjustment system of the present invention.

[0034] Figure 10 This is a partial schematic diagram of the overall adjustment system of the present invention. Figure 1 .

[0035] Figure 11 This is a partial schematic diagram of the overall adjustment system of the present invention. Figure 2 .

[0036] Figure 12 This is a partial schematic diagram of the overall adjustment system of the present invention. Figure 3 .

[0037] Figure 13 This is a partial schematic diagram of the overall adjustment system of the present invention. Figure 4 .

[0038] Reference numerals in the attached diagram: Detection body 1; Oil circuit switching valve 2200; Stop solenoid valves 2222, 2223, 2224, 2225; Shut-off valves 5210, 5211, 5212, 5213; Oil circuit shut-off valve 5214; Pilot cartridge valves DG12, DG13, DG14, DG15; Oil circuit cartridge valve DG16; Quick-closing cartridge valve DG17; Return oil cartridge valves DG40, DG41; Quick-closing solenoid valve 1842; Start solenoid valve 1843; Quick-closing test valve 2309; Manual stop valve 2250; Start oil circuit F; Pressure oil circuit P; Quick-closing oil circuit E2; Return oil circuit T; Pressure detection oil circuit P13; Test oil circuit H; Quick-closing valve 2301; Hydraulic actuators 1911, 1912; Accumulator 4600; Control system 1330. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] Please see Figure 1 - Figure 13 As shown, a four-to-two solenoid valve pressure detection component for a steam turbine speed regulation and safety system includes: an oil circuit switching valve 2200 fixed on the detection body 1. refer to Figures 8 to 13, four stop electromagnetic valves 2222, 2223, 2224, 2225; for example: stop electromagnetic valve one 2222, stop electromagnetic valve two 2223, stop electromagnetic valve three 2224, stop electromagnetic valve four 2225; With reference to Figures 8 to 13 , four stop valves 5210, 5211, 5212, 5213; for example: stop valve one 5210, stop valve two 5211, stop valve three 5212, stop valve four 5213; With reference to Figures 8 to 13 , an oil line stop valve 5214; four pilot cartridge valves DG12, DG13, DG14, DG15; for example: pilot cartridge valve one DG12, pilot cartridge valve two DG13, pilot cartridge valve three DG14, pilot cartridge valve four DG15; With reference to Figures 8 to 13 , an oil line cartridge valve DG16, a quick closing cartridge valve DG17, two oil return cartridge valves DG40, DG41; for example: oil return cartridge valve one DG40, oil return cartridge valve two DG41; With reference to Figures 8 to 13 , a quick closing electromagnetic valve 1842, a starting electromagnetic valve 1843, a quick closing test valve 2309 and a manual stop valve 2250, the detection main body 1 is provided with a starting oil line F, a pressure oil line P, a quick closing oil line E2, an oil return oil line T, a pressure detection oil line P13 and a test oil line H, With reference to Figures 8 to 13 , the front ends of the oil inlets of the four stop electromagnetic valves 2222, 2223, 2224, 2225 are respectively connected in series with a stop valve 5210, 5211, 5212, 5213; With reference to Figures 8 to 13 , the rear ends of the oil outlets of the four stop electromagnetic valves 2222, 2223, 2224, 2225 are respectively connected to the control cavities of a pilot cartridge valve DG12, DG13, DG14, DG15; With reference to Figures 8 to 13 , the oil inlets of two stop electromagnetic valves 2222, 2224 are connected in series as a group, and the oil inlets of two stop electromagnetic valves 2223, 2225 are connected in series as a group, and then connected in parallel to the pressure oil line P; With reference to Figures 8 to 13 , the oil outlets of the four pilot cartridge valves DG12, DG13, DG14, DG15 are connected in parallel to the pressure detection oil line P13; With reference to Figures 8 to 13 , the pressure detection oil line P13 is connected to the control cavities of two oil return cartridge valves DG40, DG41 which are connected in parallel; With reference to Figures 8 to 13The oil inlet of the two return oil plug-in valves DG40 and DG41 is communicated with the quick closing oil path E2, and the oil outlet is communicated with the return oil path T. When all the four stop electromagnetic valves 2222, 2223, 2224 and 2225 are powered, the pressure oil is used to increase the pressure of the pressure detection oil path P13 through the pilot plug-in valve, the two return oil plug-in valves DG40 and DG41 are closed, and the quick closing oil path E2 is pressure-kept. When two different groups of stop electromagnetic valves are simultaneously de-energized: two stop electromagnetic valves 2222 and 2223, two stop electromagnetic valves 2222 and 2225, two stop electromagnetic valves 2224 and 2223, or two stop electromagnetic valves 2224 and 2225 are simultaneously de-energized, the pressure detection oil path P13 is depressurized, the two return oil plug-in valves DG40 and DG41 are opened, and the quick closing oil path E2 is depressurized. When two same groups of stop electromagnetic valves are simultaneously de-energized: two stop electromagnetic valves 2222 and 2224 or two stop electromagnetic valves 2223 and 2225 are simultaneously de-energized, the quick closing oil path E2 is not depressurized.

[0041] In the specific implementation, the detection main body 1 is an integrated oil path block, and the inside is precisely processed with a starting oil path F, a pressure oil path P, a quick closing oil path E2, a return oil path T, a pressure detection oil path P13 and a test oil path H.

[0042] The front ends of the oil inlets of the four stop electromagnetic valves 2222, 2223, 2224 and 2225 are respectively connected in series with stop valves 5210, 5211, 5212 and 5213, which facilitates online isolation of a single electromagnetic valve for maintenance.

[0043] The oil inlets of the two stop electromagnetic valves 2222 and 2224 are connected in series as a group, the oil inlets of the two stop electromagnetic valves 2223 and 2225 are connected in series as a group, and then connected in parallel to the pressure oil path P.

[0044] The oil outlets are respectively connected to the control cavities of the corresponding pilot plug-in valves DG12, DG13, DG14 and DG15. The oil outlets of all the pilot plug-in valves DG12, DG13, DG14 and DG15 are connected in parallel into the pressure detection oil path P13, and the pressure detection oil path P13 is connected to the control cavities of the two parallel return oil plug-in valves DG40 and DG41.

[0045] Working principle: when the four stop electromagnetic valves 2222, 2223, 2224, 2225 are normally powered, the pressure oil enters the pressure detection oil way P13 through the pilot cartridge valve DG12, DG13, DG14, DG15, so that the pressure is established and maintained at 0.8-1.1 MPa, and the pressure acts on the control cavities of the return oil cartridge valves DG40, DG41 to overcome the spring force to make them closed, thereby blocking the discharge channel of the E2 oil way to the return oil way T, ensuring the pressure of the E2 oil way, and the system is in the standby running state.

[0046] When two or more of the four stop electromagnetic valves are powered off, for example: when two stop electromagnetic valves 2222, 2223; two stop electromagnetic valves 2222, 2225; two stop electromagnetic valves 2224, 2223; two stop electromagnetic valves 2224, 2225; three stop electromagnetic valves 2222, 2223, 2225 or three stop electromagnetic valves 2224, 2223, 2225 are powered off in any combination, the corresponding pilot cartridge valve control cavity will lose pressure and open, causing the pressure detection oil way P13 to rapidly depressurize through the return port of the powered-off stop electromagnetic valve.

[0047] When the pressure of the pressure detection oil way P13 drops below about 0.35 MPa, the return oil cartridge valves DG40, DG41 open under the action of the internal spring, connecting the E2 oil way with the return oil way T to depressurize, thereby triggering the quick closing of the quick closing valve 2301 to achieve emergency shutdown protection.

[0048] The "four-to-two" will not cause overall false shutdown in single-point or double-point failure, greatly improving the overall stable operation, and only when more serious multiple failures occur will the overall shutdown be caused.

[0049] Reference Figures 1 to 9 Further, the manual stop valve 2250 is connected to the pressure oil way P. The return ports of the oil way switching valve 2200, the quick closing electromagnetic valve 1842, the starting electromagnetic valve 1843, the quick closing test valve 2309, the manual stop valve 2250, and the four stop electromagnetic valves 2222, 2223, 2224, 2225 are connected in parallel to the return oil way T.

[0050] In specific implementation, the return oil way T ensures the coordination of the actions of the execution elements.

[0051] The manual stop valve 2250 is connected to the pressure oil way P, and the overall shutdown can be achieved manually.

[0052] The return oil ports of the oil way switching valve 2200, the quick closing electromagnetic valve 1842, the starting electromagnetic valve 1843, the quick closing test valve 2309, the manual stop valve 2250 and the four stop electromagnetic valves 2222, 2223, 2224 and 2225 are all connected in parallel on a common return oil way T. The oil way structure is simplified, the potential leakage points are reduced, and it is ensured that the return oil of all valve components can return to the oil tank smoothly and without obstruction when the valve components are in action, thereby avoiding the problem of slow action or failure of the valve components due to too high return oil back pressure and ensuring the rapidity and accuracy of the response of the whole system.

[0053] Reference Figures 1 to 9 Further, the oil way cut-off valve 5214 is fixedly connected between the pressure detection oil way P13 and the control cavities of the two return oil cartridge valves DG40 and DG41.

[0054] In specific implementation, the oil way cut-off valve 5214 added between the pressure detection oil way P13 and the control cavities of the two return oil cartridge valves DG40 and DG41 is a key safety and maintenance isolation point.

[0055] When the system is in normal operation, the oil way cut-off valve 5214 is kept fully open and does not affect the control of the return oil cartridge valves DG40 and DG41 by the pressure detection oil way P13. When it is necessary to perform online test of the system, such as simulating failure of the pressure detection oil way, or it is necessary to maintain the return oil cartridge valves and their associated pipelines, the oil way cut-off valve 5214 can be closed. The pressure detection oil way P13 and the execution components (the return oil cartridge valves) are isolated, allowing personnel to safely perform related tests or maintenance work without causing the whole security system to exit operation, thereby enhancing the maintainability and online processing capacity of the system.

[0056] Reference Figures 1 to 9 Further, the quick closing valve 2301 drive circuit is further included; The quick closing valve 2301 drive circuit includes: The oil way cartridge valve DG16 is arranged in the oil way switching valve 2200, and the oil way cartridge valve DG16 is controlled by the starting electromagnetic valve 1843 to open and close, and is used for conducting or cutting off the pressure oil of the starting oil way F; The oil inlet of the quick closing cartridge valve DG17 is connected to the pressure oil way P, and the oil outlet is connected to the quick closing oil way E2; The control cavity of the quick closing cartridge valve DG17 is controlled by the quick closing electromagnetic valve 1842, and the outlet of the quick closing electromagnetic valve 1842 is connected to the control cavity of the quick closing cartridge valve DG17; When the quick closing electromagnetic valve 1842 is powered, the quick closing cartridge valve DG17 is driven to close the oil way cartridge valve DG16; and when the quick closing electromagnetic valve 1842 is powered off, the quick closing cartridge valve DG17 is opened.

[0057] In the specific implementation, the quick closing valve 2301 drive circuit is integrated in the detection main body 1, including the oil way plug-in valve DG16 inside the oil way switching valve 2200 and the independent quick closing plug-in valve DG17.

[0058] The oil way plug-in valve DG16 is controlled by the starting electromagnetic valve 1843, and the function thereof is to turn on or turn off the pressure oil to the starting oil way F.

[0059] The oil inlet of the quick closing plug-in valve DG17 is connected with the pressure oil way P, and the oil outlet is connected with the quick closing oil way E2, and the control cavity thereof is controlled by the quick closing electromagnetic valve 1842.

[0060] Working principle: when the quick closing electromagnetic valve 1842 is powered on, the pilot pressure oil output by the quick closing electromagnetic valve 1842 acts on the control cavity of the quick closing plug-in valve DG17, so that the quick closing plug-in valve DG17 is closed, thereby cutting off the oil supply of the pressure oil way P to the quick closing oil way E2.

[0061] When the quick closing electromagnetic valve 1842 is powered off, the control cavity of the quick closing plug-in valve DG17 is depressurized, and the quick closing plug-in valve DG17 is opened under the action of the spring, so that the pressure oil can enter the quick closing oil way E2.

[0062] The electromagnetic control of the quick closing oil way E2 established by the oil pressure control is realized, and the starting electromagnetic valve 1843 is coordinated to complete the orderly control of the quick closing valve 2301.

[0063] The quick closing valve 2301 is a valve on a steam turbine.

[0064] The components on the steam turbine include: the quick closing valve 2301; the oil motor 1911, 1912; the energy accumulator 4600; the control system 1330 (steam turbine control room); Reference Figures 8 to 13 Further, the oil return port of the starting electromagnetic valve 1843 is provided with a throttling device.

[0065] In the specific implementation, the throttling device is a throttling hole or an adjustable throttling valve.

[0066] Reference Figures 8 to 13 Further, two electromagnetic converters are connected in parallel after the switching valve on the pressure oil way P.

[0067] In the specific implementation, the two electromagnetic converters are arranged, when one of the electromagnetic converters fails, the other electromagnetic converter can still be used normally, which can effectively avoid shutdown.

[0068] Reference Figures 8 to 13 Electro-hydraulic converter action When the four shutdown electromagnetic valves 2222, 2223, 2224 and 2225 are powered on, the manual shutdown valve 2250 is reset, and the quick closing electromagnetic valve 1842 is opened: 1. Simultaneously give two redundant electro-hydraulic converters two 4-20MA current signals, and the oil motor opens from 0 to full; 2. The electro-hydraulic converter is two in a group, and works online at the same time. When one of them fails, the other one works normally, and will not cause the turbine to trip (the original design is one electro-hydraulic converter, which will cause the turbine to trip when the electro-hydraulic converter fails).

[0069] The use of the electro-hydraulic converter adopts the prior art.

[0070] A use method applied to a four-to-two pressure detection assembly of an electromagnetic valve for a turbine speed regulation and safety system, the use method comprising: S1: confirming that the four shutdown electromagnetic valves 2222, 2223, 2224 and 2225 are powered, monitoring that the pressure of the pressure detection oil circuit P13 is 0.8-1.1 MPa, and keeping the speed closing oil circuit E2 at pressure; S2: simultaneously powering the starting electromagnetic valve 1843 and the speed closing electromagnetic valve 1842, powering the starting electromagnetic valve 1843 to drive the oil circuit plug-in valve DG16 to open and establish the starting oil circuit F, and powering the speed closing electromagnetic valve 1842 to drive the speed closing plug-in valve DG17 and the oil circuit plug-in valve DG16 to cut off the passage of the pressure oil P to the speed closing oil circuit E2; S3: after a first delay, powering off the speed closing electromagnetic valve 1842 to establish the speed closing oil circuit E2; S4: after a second delay, powering off the starting electromagnetic valve 1843, throttling the starting oil circuit F to release pressure, and slowly opening the speed closing valve 2301.

[0071] In specific implementation, first, step S1 is performed: confirming that the four shutdown electromagnetic valves are all powered, at this time, the pressure detection oil circuit P13 establishes a normal pressure of 0.8-1.1 MPa, the oil return plug-in valves DG40 and DG41 are closed, the speed closing oil circuit E2 is in a pressure keeping state, and the system allows starting.

[0072] Then, step S2 is performed: simultaneously powering the starting electromagnetic valve 1843 and the speed closing electromagnetic valve 1842.

[0073] After the starting electromagnetic valve 1843 is powered, the drive oil circuit plug-in valve DG16 is opened, the pressure oil enters the starting oil circuit F, and the opening condition of the speed closing valve 2301 is prepared; the speed closing electromagnetic valve 1842 is powered to drive the speed closing plug-in valve DG17 to close, so as to ensure that the pressure oil does not enter the speed closing oil circuit E2.

[0074] After a first delay, for example, 2-3 seconds, Step S3 is performed: powering off the speed closing electromagnetic valve 1842 first. The speed closing electromagnetic valve 1842 is powered off to cause the speed closing plug-in valve DG17 to open, and the pressure oil rapidly enters and establishes the pressure of the speed closing oil circuit E2.

[0075] After a second delay, for example, 5-10 seconds, Step S4 is performed: the starting solenoid valve 1843 is de-energized. After the starting solenoid valve 1843 is de-energized, the oil way plug-in valve DG16 is closed, and the oil in the starting oil way F is slowly discharged through the throttle device provided at the oil return port thereof.

[0076] Since the pressure in the starting oil way F is slowly decreased, and the pressure in the quick closing oil way E2 is built up, the quick closing valve 2301 is smoothly and slowly opened under the differential pressure between the two sides thereof, so that the impact of the steam turbine admission valve is avoided, and the smooth start of the steam turbine is realized.

[0077] Reference Figures 8 to 13 Further, the emergency stop step further comprises: when any one of the following combinations of two stop solenoid valves 2222, 2223, 2222, 2225, 2224, 2223 or 2224, 2225 is de-energized at the same time, or when the manual stop valve 2250 is operated, the pressure in the pressure detection oil way P13 is discharged to below 0.35 MPa, the oil return plug-in valve DG40 is opened, and the pressure in the quick closing oil way E2 is discharged, so that the quick closing valve 2301 is quickly closed.

[0078] The specific combinations of two or more stop solenoid valves de-energized at the same time are as follows: two stop solenoid valves 2222, 2223; two stop solenoid valves 2222, 2225; two stop solenoid valves 2224, 2223; two stop solenoid valves 2224, 2225; three stop solenoid valves 2222, 2223, 2225; and three stop solenoid valves 2224, 2223, 2225.

[0079] Remote emergency stop embodiment: When it is necessary to remotely close the quick closing valve 2301, the four stop solenoid valves 2222, 2223, 2224, 2225 are de-energized, the oil chambers of the oil return plug-in valves DG40, DG41 are de-pressurized, the oil return plug-in valves DG40, DG41 are opened under the action of the spring force, the quick closing oil way E2 is communicated with the oil return oil way T, the quick closing oil is quickly discharged, and the quick closing valve 2301 is closed. (If any three of the four solenoid valves are de-energized, the quick closing valve 2301 can also be ensured to be closed.)

[0080] On-site emergency stop embodiment: The safety device of the manual stop valve 2250 is opened, the handle of the manual stop valve 2250 is pushed forward, and the quick closing valve 2301 is quickly closed. The working principle is the same as that of the four stop solenoid valves 2222, 2223, 2224, 2225.

[0081] Four-to-two embodiment: P oil 0.8-1.1MPA, quick closing solenoid valve 1842 opens, when any two of the solenoid valves 2222, 2223, 2224, 2225 lose power, the action is as follows.

[0082] P = 1.0MPA ① stop solenoid valves 2222, 2223 lose power (stop), P13<0.35MPA, quick closing solenoid valve 1842 closes.

[0083] ② stop solenoid valves 2222, 2224 lose power (not stop), P13=0, quick closing solenoid valve 1842 does not close.

[0084] ③ stop solenoid valves 2222, 2225 lose power (stop), P13<0.35MPA, quick closing solenoid valve 1842 closes.

[0085] ④ stop solenoid valves 2223, 2224 lose power (stop), P13<0.35MPA, quick closing solenoid valve 1842 closes.

[0086] ⑤ stop solenoid valves 2223, 2225 lose power (not stop), P13=0.8-1.0MPA, quick closing solenoid valve 1842 does not close.

[0087] ⑥ stop solenoid valves 2224, 2225 lose power (stop), P13<0.35MPA, quick closing solenoid valve 1842 closes.

[0088] Online replacement solenoid valve function oil line stop valve 5214 closes, P13=0 1. Close stop valve 5210, remove stop solenoid valve 2222.

[0089] 2. Close stop valve 5211, remove stop solenoid valve 2223.

[0090] 3. Close stop valve 5212, remove stop solenoid valve 2224.

[0091] 4. Close stop valve 5213, remove stop solenoid valve 2225.

[0092] In specific implementation, when the control system issues a stop command or a fault occurs requiring emergency stop, it can be triggered in two main ways: One is to make any one combination of two stop solenoid valves 2222, 2223; two stop solenoid valves 2222, 2225; two stop solenoid valves 2224, 2223; two stop solenoid valves 2224, 2225; three stop solenoid valves 2222, 2223, 2225 or three stop solenoid valves 2224, 2223, 2225 lose power at the same time; Second, the manual stop valve 2250 is operated on site.

[0093] As a result, the pressure in the pressure detection oil line P13 is rapidly discharged through the return port of the de-energized electromagnetic valve or the manual valve.

[0094] When the pressure in the pressure detection oil line P13 drops below the set value of 0.35 MPa, the control pressure of the two return plug-in valves DG40 and DG41 is insufficient, and they are quickly opened under the action of the spring force, directly connecting the quick-closing oil line E2 with the return oil line T.

[0095] This causes the high-pressure oil in the E2 oil line to be rapidly discharged, and the quick-closing test valve is quickly closed under the action of the internal spring or additional force, cutting off the main steam entering the steam turbine, achieving millisecond-level response emergency shutdown, and ensuring the safety of the unit.

[0096] Further, it also includes an online test step: energizing the quick-closing test valve 2309 to introduce pressure oil into the test oil line H to partially offset the pressure of the quick-closing oil line E2, so that the quick-closing test valve 2309 produces partial displacement for testing, and does not trigger its complete closure.

[0097] Quick-closing valve test embodiment (external quick-closing valve 2301 connected to F, H1, and E2): When the quick-closing electromagnetic valve 1842 is opened, the quick-closing test valve 2309 is energized, allowing H to be connected to the pressure oil P, and the quick-closing valve 2301 is tested online.

[0098] To stop the test, only the quick-closing test valve 2309 needs to be de-energized. Because of the throttling orifice plate, the quick-closing electromagnetic valve 1842 has slow partial displacement and reset actions, and the quick-closing valve 2301 will not close.

[0099] The online test function allows the partial function of the quick-closing test valve to be tested during normal operation of the steam turbine without the need to shut down.

[0100] This is achieved by energizing the quick-closing test valve 2309 (usually referring to the test electromagnetic valve associated with it).

[0101] When the test electromagnetic valve is energized, it introduces a flow of control oil from the pressure oil line P into the test oil line H.

[0102] The test oil line H is usually connected to a certain specific chamber of the quick-closing test valve piston, and the force generated by it is in the opposite direction to the valve-closing force acting on the piston by the quick-closing oil line E2.

[0103] The introduced test oil pressure partially offsets the pressure of the E2 oil line, so that the net closing force acting on the quick closing test valve is reduced, resulting in a small, controllable closing displacement (e.g. 1-2 mm) of the quick closing test valve, but far from reaching the level of complete closing.

[0104] By monitoring this displacement signal or related pressure change, the activity of the quick closing test valve and the function of its closing circuit can be verified, thus completing an important valve activity test without shutdown, and improving the predictive maintenance capability of the equipment.

[0105] Further, it also includes the step of online replacing the shutdown solenoid valve: closing the corresponding stop valve 5210, 5211, 5212, 5213 before the oil inlet of the solenoid valve to be replaced, and closing the oil line stop valve 5214, so that the solenoid valve can be disassembled and assembled online, and the "four out of two" protection function of the system is maintained by the remaining normal shutdown solenoid valves.

[0106] In specific implementation, the step of online replacing the shutdown solenoid valve fully embodies the advantage of the maintenance convenience of the "four out of two" system.

[0107] When a certain shutdown solenoid valve, for example 2222, is diagnosed as faulty and needs to be replaced, first close the corresponding stop valve, i.e. stop valve one 5210, at the front end of the oil inlet of the solenoid valve, to cut off the pressure oil supply to the solenoid valve.

[0108] Subsequently, the oil line stop valve 5214 downstream of the pressure detection oil line P13 is closed, which is to prevent the pressure of the pressure detection oil line P13 from being completely released when the solenoid valve is disassembled and assembled, so as to maintain the protection function of the system.

[0109] After the above isolation is completed, the faulty shutdown solenoid valve 2222 can be disassembled and replaced online using tools.

[0110] During the replacement operation, although one shutdown solenoid valve is isolated, the remaining three normal shutdown solenoid valves are still working.

[0111] The system still maintains the "three out of two" logic (essentially a degraded operation of the "four out of two" logic), that is, if any other solenoid valve fails, the system can still trigger the shutdown protection correctly.

[0112] This means that the maintenance work can be safely carried out without affecting the continuous operation of the unit, greatly improving the availability of the equipment. After the replacement and testing of the new solenoid valve are completed, the complete "four out of two" function of the system can be restored by opening the stop valves in reverse order.

[0113] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting; it is not intended to exclude myriad other embodiments of the present application that other presenters can develop. It is also possible, however, that only a single element can be present. It is further noted that such a term as "comprising" is intended to mean that the embodiments include the recited elements, but not excluding other elements. "Consisting essentially of when used herein in relation to a composition, means that the composition includes the recited elements, and can include additional elements, so long as the additional elements do not materially alter the basic and novel characteristics of the claimed composition. "Consisting of" when used herein in relation to a composition, means that the composition includes the recited elements, and no additional elements.

[0114] The preferred embodiments of the application disclosed above are only to help explain the principles of the present application. The preferred embodiments do not describe all the details of the present application, nor limit the present application to only the specific embodiments described. It is apparent that many modifications and variations can be made to the present application based on the content of the present disclosure. The present disclosure selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present application, so that those skilled in the art can well understand and utilize the present application. The present application is limited only by the claims and their full scope and equivalents.

Claims

1. A solenoid valve four-to-two pressure detection assembly for a turbine governor protection system, comprising: The detection main body (1) is fixed with an oil way switching valve (2200), four stop electromagnetic valves (2222, 2223, 2224, 2225), four stop valves (5210, 5211, 5212, 5213), an oil way stop valve (5214), four pilot cartridge valves (DG12, DG13, DG14, DG15), an oil way cartridge valve (DG16), a quick closing cartridge valve (DG17), two oil return cartridge valves (DG40, DG41), a quick closing electromagnetic valve (1842), a starting electromagnetic valve (1843), a quick closing test valve (2309) and a manual stop valve (2250), and the detection main body (1) is provided with a starting oil way (F), a pressure oil way (P), a quick closing oil way (E2), an oil return oil way (T), a pressure detection oil way (P13) and a test oil way (H), characterized in that: The front end of the oil inlet of each of the four stop electromagnetic valves (2222, 2223, 2224, 2225) is connected in series with a stop valve (5210, 5211, 5212, 5213); The rear end of the oil outlet of each of the four stop electromagnetic valves (2222, 2223, 2224, 2225) is connected to the control cavity of a pilot cartridge valve (DG12, DG13, DG14, DG15); The oil inlets of two stop electromagnetic valves (2222, 2224) are connected in series as a group, and the oil inlets of the other two stop electromagnetic valves (2223, 2225) are connected in series as another group, and the two groups are connected in parallel to the pressure oil way (P); The oil outlets of the four pilot cartridge valves (DG12, DG13, DG14, DG15) are connected in parallel to the pressure detection oil way (P13); The pressure detection oil way (P13) is connected to the control cavities of two parallel oil return cartridge valves (DG40, DG41); The oil inlets of the two oil return cartridge valves (DG40, DG41) are communicated with the quick closing oil way (E2), and the oil outlets are communicated with the oil return oil way (T); When all the four stop electromagnetic valves (2222, 2223, 2224, 2225) are powered, the pressure detection oil way (P13) is pressurized by the pilot cartridge valves, the two oil return cartridge valves (DG40, DG41) are closed, and the quick closing oil way (E2) is pressurized; When two different groups of stop electromagnetic valves lose power at the same time: when two stop electromagnetic valves (2222, 2223), two stop electromagnetic valves (2222, 2225), two stop electromagnetic valves (2224, 2223) or two stop electromagnetic valves (2224, 2225) lose power at the same time, the pressure detection oil way (P13) is depressurized, the two oil return cartridge valves (DG40, DG41) are opened, and the quick closing oil way (E2) is depressurized. When two of the same group of shutdown solenoid valves lose power at the same time: when two of the same group of shutdown solenoid valves (2222, 2224) or two of the same group of shutdown solenoid valves (2223, 2225) lose power at the same time, the quick closing oil way (E2) is not depressurized.

2. The electromagnetic valve four-to-two pressure detection assembly for a steam turbine governing and protection system according to claim 1, characterized in that: The pressure oil way (P) is connected with the manual shutdown valve (2250); The oil return ports of the oil way switching valve (2200), the quick closing solenoid valve (1842), the starting solenoid valve (1843), the quick closing test valve (2309), the manual shutdown valve (2250), and the four shutdown solenoid valves (2222, 2223, 2224, 2225) are connected in parallel on the oil return oil way (T).

3. The solenoid valve four-to-two pressure detection assembly for a steam turbine governing and protection system according to claim 2, characterized in that: The pressure detection oil way (P13) and the control cavities of the two oil return cartridge valves (DG40, DG41) are fixedly connected with the oil way stop valve (5214).

4. The electromagnetic valve four-to-two pressure detection assembly for a steam turbine governing and protection system according to claim 3, characterized in that: It further comprises a quick closing valve (2301) drive circuit; The quick closing valve (2301) drive circuit comprises: The oil way cartridge valve (DG16) is arranged in the oil way switching valve (2200), and the oil way cartridge valve (DG16) is controlled by the starting solenoid valve (1843) to open and close, for conducting or cutting off the pressure oil of the starting oil way (F); The oil inlet of the quick closing cartridge valve (DG17) is connected with the pressure oil way (P), and the oil outlet is connected with the quick closing oil way (E2); The control cavity of the quick closing cartridge valve (DG17) is controlled by the quick closing solenoid valve (1842), and the outlet of the quick closing solenoid valve (1842) is connected to the control cavity of the quick closing cartridge valve (DG17); When the quick closing solenoid valve (1842) is powered, the quick closing cartridge valve (DG17) is driven to close the oil way cartridge valve (DG16); when the quick closing solenoid valve (1842) loses power, the quick closing cartridge valve (DG17) is opened.

5. The solenoid valve four-to-two pressure detection assembly for a steam turbine governing and protection system according to claim 4, characterized in that: The oil return port of the starting solenoid valve (1843) is provided with a throttling device.

6. The solenoid valve four-to-two pressure detection assembly for a steam turbine governing and protection system according to claim 1, characterized in that: The pressure oil way (P) is connected with the switching valve, and two electromagnetic transducers are connected in parallel after the switching valve.

7. A method of use, characterized by: The method for using the electromagnetic valve four-to-two pressure detection assembly for a steam turbine governing and protection system according to claim 4 or 5 comprises: S1: confirming that the four shutdown solenoid valves (2222, 2223, 2224, 2225) are powered, monitoring that the pressure of the pressure detection oil way (P13) is 0.8-1.1 MPa, and keeping the pressure of the quick closing oil way (E2); S2: simultaneously powering the starting solenoid valve (1843) and the quick closing solenoid valve (1842), powering the starting solenoid valve (1843) to drive the oil way cartridge valve (DG16) to open and establish the starting oil way (F), and powering the quick closing solenoid valve (1842) to drive the quick closing cartridge valve (DG17) and the oil way cartridge valve (DG16) to cut off the passage of the pressure oil (P) to the quick closing oil way (E2). S3: After the first delay, the quick closing solenoid valve (1842) is de-energized to establish the quick closing oil path (E2); S4: After the second delay, the starting solenoid valve (1843) is de-energized, the starting oil path (F) is throttled to release pressure, and the quick closing valve (2301) is slowly opened.

8. The method of use of claim 7, wherein: An emergency shutdown step is also included: when any one of the following combinations of the two shutdown solenoid valves (2222, 2223), the two shutdown solenoid valves (2222, 2225), the two shutdown solenoid valves (2224, 2223), or the two shutdown solenoid valves (2224, 2225) are simultaneously de-energized, or when the manual shutdown valve (2250) is operated, the pressure in the pressure detection oil path (P13) is released to below 0.35 MPa, the return oil plug-in valve (DG40) is opened, the pressure in the quick closing oil path (E2) is released, and the quick closing valve (2301) is quickly closed.

9. The method of use of claim 8, wherein: An online test step is also included: the quick closing test valve (2309) is energized, pressure oil is introduced into the test oil path (H) to partially offset the pressure in the quick closing oil path (E2), the quick closing test valve (2309) is partially displaced for testing, and complete closure is not triggered.

10. The method of use of claim 9, wherein: An online replacement of the shutdown solenoid valve step is also included: the corresponding shut-off valve (5210, 5211, 5212, 5213) before the oil inlet of the solenoid valve to be replaced is closed, and the oil path shut-off valve (5214) is closed, so that the solenoid valve can be disassembled and assembled online, and the "four out of two" protection function of the system is maintained by the remaining normal shutdown solenoid valves.

Images