Turbine high-pressure interrupting device with isolation test and on-line maintenance functions

Abstract

The utility model discloses a steam turbine high-pressure interrupting device with isolation test and on-line maintenance functions. The steam turbine high-pressure interrupting device comprises a system safety oil way and a simulation safety oil way. The pilot electromagnetic valve 4YV is connected with the isolating valve; the isolating valve is connected with a first travel switch ZS6 and a second travel switch ZS7, and signals of the first travel switch ZS6 and the second travel switch ZS7 are used for DEH to judge the state of the isolating valve; the manual stop valve is used for cutting off the simulated safety oil during online fault processing; a first electromagnetic valve 5YV and a first unloading valve are arranged in the interruption module and are connected with a third electromagnetic valve 7YV and a third unloading valve in an oil way in parallel; a second electromagnetic valve 6YV and a second unloading valve are connected with a fourth electromagnetic valve 8YV and a fourth unloading valve in an oil way in parallel; and a third throttling hole, a second pressure transmitter PT2 and a fourth throttling hole are arranged in the series oil path. The high-voltage interruption module has the advantages that blocking and leakage faults of the electromagnetic valve, the unloading valve and the throttling hole can be processed on line, the whole high-voltage interruption module is high in intelligent degree, and on-line state monitoring is facilitated.

Description

Technical Field

[0001] The utility model relates to the field of steam turbines with isolation test and online maintenance functions, in particular to a steam turbine high-pressure tripping device with isolation test and online maintenance functions. Background Art

[0002] In the DEH control system of some domestic steam turbine generator sets of 350MW and above, in addition to the isolation valve group, the high-pressure isolation module plays a more crucial protective role. Its task is to accept the instructions of the DEH or ETS control system, and quickly drain the safety oil of each oil motor, quickly close each valve, and cut off the steam inlet of the unit when an emergency occurs that endangers the safety of the unit operation. The high-pressure isolation module is the main hub for controlling the safety oil in the entire EH system. In order to ensure the safety and reliability of its operation, a structure of four electromagnetic isolation valves connected in parallel and then in series is adopted, and the electromagnetic valves can be tested for activity online (twenty-five countermeasures requirements). Because these four electromagnetic valves are energized for a long time, the springs are in a compressed state, and there is no action in normal operation, so it is necessary to conduct activity tests regularly to determine whether these four electromagnetic valves are in a normal state. However, due to various reasons, the electromagnetic valves and unloading valves are often stuck, the throttle holes are blocked, and even oil leakage occurs during testing or operation. Because it is forbidden to set a stop valve on the safety oil line, and the loss of safety oil will cause the unit to trip, it seriously affects the safe and reliable operation of the unit.

[0003] Therefore, it is necessary to design a device that can handle solenoid valve, unloading valve, throttle hole blockage, and external leakage failures online. Any problems that occur during online testing will not affect the operation of the unit. The online test state can be switched to the normal operating state safely without oil disturbance. The entire high-pressure shut-off module is highly intelligent, and a steam turbine high-pressure shut-off device with isolation test and online maintenance functions that is convenient for online status monitoring is very necessary. Utility Model Content

[0004] The utility model provides a steam turbine high-pressure tripping device with isolation test and online maintenance functions, which can solve the problems mentioned in the background technology.

[0005] The utility model provides a steam turbine high-pressure shutoff device with isolation test and online maintenance functions, including a system safety oil circuit, a simulated safety oil circuit, an isolation device, and a shutoff module; the system safety oil circuit includes a first throttle hole, a first pressure switch PS1, a second pressure switch PS2, a third pressure switch PS3 and a first pressure gauge; the simulated safety oil circuit includes a second throttle hole, a manual stop valve, a second pressure gauge, and a first pressure transmitter PT1; the isolation device includes a pilot solenoid valve 4YV, an isolation valve, a first travel switch ZS6 and a second travel switch ZS7; the shutoff module includes a first solenoid valve 5YV, a first unloading valve, a second solenoid valve 6YV, a second unloading valve, a second pressure transmitter PT2, a third solenoid valve 7YV, a third unloading valve, a fourth solenoid valve 8YV, a fourth unloading valve, a third throttle hole and a fourth throttle hole; the system safety oil circuit is provided with The first throttle hole, the first pressure switch PS1, the second pressure switch PS2, the third pressure switch PS3 and the first pressure gauge; the pressure oil forms the system safety oil through the first throttle hole and flows to each oil motor of the EH system. The safety oil pressure is determined by taking two out of three signals of the first pressure switch PS1, the second pressure switch PS2 and the third pressure switch PS3. The ETS outputs the command to quickly close the oil motor, and the first pressure gauge displays the safety oil pressure on the spot; the simulated safety oil circuit is provided with the second throttle hole, the manual stop valve, the second pressure gauge, the first pressure transmitter PT1, the pilot solenoid valve 4YV, the isolation valve, the first travel switch ZS6 and the second travel switch ZS7; the pilot solenoid valve 4YV is connected to the isolation valve; the isolation valve is connected to the first travel switch ZS6 and the second travel switch ZS7; the pressure oil forms the simulated safety oil circuit through the second throttle hole and flows to the shut-off module through the isolation valve. The second pressure gauge displays the simulated safety oil pressure locally, and the first pressure transmitter signal transmits the simulated safety oil pressure signal to DEH remotely as a judgment condition for test permission and test end switching; the first travel switch ZS6 and the second travel switch ZS7 signals are used by DEH to judge the state of the isolation valve; the manual stop valve is used to cut off the simulated safety oil when handling faults online; the first solenoid valve 5YV, the first unloading valve and the third solenoid valve 7YV, the third unloading valve oil circuit is connected in parallel in the shut-off module and is referred to as the front stage here, the second solenoid valve 6YV, the second unloading valve and the fourth solenoid valve 8YV, the fourth unloading valve oil circuit is connected in parallel and is referred to as the rear stage here, and the front stage and the rear stage oil circuits are connected in series; the third throttle hole, the second pressure transmitter PT2 and the fourth throttle hole are provided in the series oil circuit.

[0006] Preferably, it also includes corresponding control logic of DEH and ETS control systems.

[0007] Preferably, the first pressure switch PS1, the second pressure switch PS2 and the third pressure switch PS3 are independent sampling pressure switches divided into three positions according to 25 countermeasures.

[0008] Preferably, the simulated safety oil circuit generates simulated safety oil through the pilot solenoid valve 4YV and the isolation valve, and realizes isolation, online testing and non-disturbance switching of the interruption system through the second pressure gauge, the first pressure transmitter, the first travel switch ZS6 and the second travel switch ZS7.

[0009] Preferably, the simulated safety oil circuit generates simulated safety oil through the pilot solenoid valve 4YV and the isolation valve, and realizes online accident processing through the second pressure gauge, the first pressure transmitter, the first travel switch ZS6, the second travel switch ZS7, and the manual stop valve.

[0010] The utility model provides the following beneficial effects:

[0011] 1. The steam turbine high-pressure tripping device with isolation test and online maintenance functions can handle the solenoid valve, unloading valve, throttle hole blockage and leakage faults online;

[0012] 2. If any problem occurs during the online test of the steam turbine high-pressure tripping device with isolation test and online maintenance functions, it will not affect the operation of the unit;

[0013] 3. The steam turbine high-pressure tripping device with isolation test and online maintenance functions switches from online test state to normal operation state with safe oil and no disturbance;

[0014] 4. The entire high-voltage shutoff module of the steam turbine high-voltage shutoff device with isolation test and online maintenance functions is highly intelligent and convenient for online status monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the structure of a steam turbine high-pressure tripping device with isolation test and online maintenance functions provided by the utility model;

[0016] Figure 2 The utility model provides a conventional high-pressure tripping module schematic diagram of a steam turbine high-pressure tripping device with isolation test and online maintenance functions.

[0017] Explanation of the accompanying drawings: 1-first pressure switch PS1; 2-second pressure switch PS2; 3-third pressure switch PS3; 4-first pressure gauge; 5-second pressure gauge; 6-first pressure transmitter PT1; 7-pilot solenoid valve 4YV; 8-first travel switch ZS6; 9-second travel switch ZS7; 10-first solenoid valve 5YV; 11-second solenoid valve 6YV; 12-second pressure transmitter PT2; 13-third solenoid valve 7YV; 14-fourth solenoid valve 8YV; 15-system safety oil circuit; 16-isolating valve; 17-manual stop valve; 18-first throttle hole; 19-second throttle hole; 20-analog safety oil circuit; 21-first unloading valve; 22-second unloading valve; 23-third unloading valve; 24-fourth unloading valve; 25-third throttle hole; 26-fourth throttle hole. DETAILED DESCRIPTION

[0018] A specific implementation of the present utility model is described in detail below in conjunction with the accompanying drawings, but it should be understood that the protection scope of the present utility model is not limited by the specific implementation mode.

[0019] like Figure 1 and Figure 2As shown, a steam turbine high-pressure shutoff device with isolation test and online maintenance functions provided by the embodiment of the utility model includes a system safety oil circuit 15, a simulated safety oil circuit 20, an isolation device, and a shutoff module; the system safety oil circuit 15 includes a first throttle hole 18, a first pressure switch PS11, a second pressure switch PS22, a third pressure switch PS33 and a first pressure gauge 4; the simulated safety oil circuit 20 includes a second throttle hole 19, a manual stop valve 17, a second pressure gauge 5, a first pressure variable transmitter PT16; the isolation device includes a pilot solenoid valve 4YV7, an isolation valve 16, a first travel switch ZS68 and a second travel switch ZS79; the cutoff module includes a first solenoid valve 5YV10, a first unloading valve 21, a second solenoid valve 6YV11, a second unloading valve 22, a second pressure transmitter PT212, a third solenoid valve 7YV13, a third unloading valve 23, a fourth solenoid valve 8YV14, a fourth unloading valve 24, a third throttle hole 25 and a fourth throttle hole 26; the system The safety oil circuit 15 is provided with a first throttle hole 18, a first pressure switch PS11, a second pressure switch PS22, a third pressure switch PS33 and a first pressure gauge 4; the pressure oil passes through the first throttle hole 18 to form the system safety oil to each oil motor of the EH system, and the safety oil pressure is determined by taking two out of three signals of the first pressure switch PS11, the second pressure switch PS22 and the third pressure switch PS33, and the ETS outputs a command to quickly close the oil motor, and the first pressure gauge 4 displays the safety oil pressure on the spot; the simulated safety oil circuit 20 is provided with a second throttle hole 19, a manual stop valve 17, a second pressure gauge 5, a first pressure transmitter PT16, a pilot solenoid valve 4YV7, an isolation valve 16, a first travel switch ZS68 and a second travel switch ZS79; the pilot solenoid valve 4YV7 is connected to the isolation valve 16; the isolation valve 16 is connected to the first travel switch ZS68 and the second travel switch ZS79; the pressure oil passes through the second throttle hole 19 to form the simulated safety oil circuit 20, and passes through the isolation valve to the shut-off module. The second pressure gauge 5 displays the simulated safety oil pressure locally, and the first pressure transmitter 6 transmits the simulated safety oil pressure signal to DEH remotely as a judgment condition for test permission and test end switching; the first travel switch ZS68 and the second travel switch ZS79 signals are used by DEH to judge the state of the isolation valve; the manual stop valve 17 is used to cut off the simulated safety oil when handling faults online; the first solenoid valve 5YV10, the first unloading valve 21 and the third solenoid valve 7YV13, the third unloading valve 23 are arranged in parallel in the isolation module, which is referred to as the front stage, and the second solenoid valve 6YV11, the second unloading valve 22 and the fourth solenoid valve 8YV14, the fourth unloading valve 24 are arranged in parallel in the oil circuit, which is referred to as the rear stage, and the front stage and the rear stage oil circuits are connected in series; the third throttle hole 25, the second pressure transmitter PT212 and the fourth throttle hole 26 are arranged in the series oil circuit.

[0020] In this embodiment, the corresponding control logic of the DEH and ETS control systems is also included.

[0021] In this embodiment, the simulated safety oil circuit 20 generates simulated safety oil through the pilot solenoid valve 4YV7 and the isolation valve 16. The isolation, online test and non-disturbance switching of the interruption system are realized through the second pressure gauge 5, the first pressure transmitter 6, the first travel switch ZS68 and the second travel switch ZS79.

[0022] In this embodiment, the simulated safety oil circuit 20 generates simulated safety oil through the pilot solenoid valve 4YV7 and the isolation valve 16. The isolation, online test and non-disturbance switching of the interruption system are realized through the second pressure gauge 5, the first pressure transmitter 6, the first travel switch ZS68 and the second travel switch ZS79.

[0023] In this embodiment, the simulated safety oil circuit 20 generates simulated safety oil through the pilot solenoid valve 4YV7 and the isolation valve 16. The second pressure gauge 5, the first pressure transmitter 6, the first travel switch ZS68, the second travel switch ZS79 and the manual stop valve 17 are used to realize online accident processing.

[0024] Working principle: During normal operation, the pressure oil forms system safety oil after passing through the throttle hole. Three independent sampling pressure switches are set in the system safety oil circuit according to 25 countermeasures in three positions: the first pressure switch PS11, the second pressure switch PS22, the third pressure switch PS33, and the first pressure gauge 4. The system safety oil enters each oil motor and the isolation valve group. At the same time, the system safety oil passes through the isolation valve and enters the two parallel and two series solenoid valves + plug-in unloading valve oil circuit. The first solenoid valve 5YV10, the second solenoid valve 6YV11, the third solenoid valve 7YV13, and the fourth solenoid valve 8YV14 are controlled by them. When an emergency situation that endangers the safety of unit operation occurs; when receiving instructions from the DEH or ETS control system, the first solenoid valve 5YV10, the second solenoid valve 6YV11 , the third solenoid valve 7YV13, the fourth solenoid valve 8YV14 lose power, quickly drain the safety oil of each oil motor, quickly close each valve, cut off the steam inlet of the unit, and conduct online activity test. The pilot solenoid valve 4YV7 of the isolation valve is energized, and the system safety oil is cut off from the isolation valve and enters the isolation state. The first stroke switch ZS68 and the second stroke switch ZS79 connected to the isolation valve can display the isolation state. After the pressure oil passes through the same throttle hole, the simulated safety oil formed passes through the isolation valve and enters the two parallel and two series solenoid valves + plug-in unloading valve oil circuit. At this time, an online test is carried out: the first solenoid valve 5YV10, the second solenoid valve 6YV11, the second pressure transmitter PT212, the third solenoid valve 7YV13, and the fourth solenoid valve 8YV144 solenoid valves act one by one. After each solenoid valve acts, the pressure in the test oil circuit where the first pressure transmitter PT16 is located will change. *Note: The test oil circuit is formed by the safety oil passing through two throttle holes of the same size. The pressure transmitter is arranged between the two throttle holes. The pressure here is half of the safety oil pressure. After the first solenoid valve 5YV10 and the third solenoid valve 7YV13 are actuated, the safety oil is connected to the test oil circuit, and the pressure increases; after the second solenoid valve 6YV11 and the fourth solenoid valve 8YV14 are actuated, the test oil circuit will be connected to the pressure-free return oil circuit, and the pressure drops. The change in pressure will cause the first pressure transmitter PT16 to send a signal. After the solenoid valve is actuated, if a signal is returned, it proves that the solenoid valve is normal. Then the solenoid valve in the test is reset, and the tests are completed one by one. *Note: The logic shields the situation where the front and rear solenoid valves are tested at the same time. Note: When a critical situation occurs, the DEH or ETS logic will quickly cut off the isolation state. When the solenoid valve is stuck, the unloading valve is stuck, or there is external leakage during online testing or operation, the isolation valve can be operated to isolate the system safety oil. At this time, the manual stop valve that simulates the safety oil circuit can be operated. When the pressure gauge is free of pressure afterwards, the jamming and oil leakage problems can be dealt with.When the fault handling is completed, slowly open the manual stop valve. At this time, when the simulated safety oil pressure is equal to the system safety oil pressure, the isolation valve can be operated to cut off the isolation state. The system safety oil continues to be controlled by the first solenoid valve 5YV10, the second solenoid valve 6YV11, the third solenoid valve 7YV13, and the fourth solenoid valve 8YV14 of the two parallel and two series solenoid valves + plug-in unloading valve oil circuit to enter the normal operating state. This device can handle solenoid valve, unloading valve, throttle hole blockage, and external leakage faults online; any problems during online testing will not affect the operation of the unit; the online test state switches to the normal operating state with no disturbance to the safety oil; the entire high-pressure isolation module is highly intelligent and convenient for online status monitoring.

[0025] The above disclosure is only a specific embodiment of the present invention, but the embodiments of the present invention are not limited thereto, and any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A steam turbine high-pressure tripping device with isolation test and online maintenance functions, characterized in that: The invention comprises a system safety oil circuit (15), a simulated safety oil circuit (20), an isolation device, and a shutoff module; the system safety oil circuit (15) comprises a first throttle hole (18), a first pressure switch PS1 (1), a second pressure switch PS2 (2), a third pressure switch PS3 (3), and a first pressure gauge (4); the simulated safety oil circuit (20) comprises a second throttle hole (19), a manual stop valve (17), a second pressure gauge (5), and a first pressure transmitter PT1 (6); the isolation device comprises a pilot solenoid valve 4YV (7), an isolation valve (16), a first travel switch ZS6 (8 ) and a second travel switch ZS7 (9); the isolation module includes a first solenoid valve 5YV (10), a first unloading valve (21), a second solenoid valve 6YV (11), a second unloading valve (22), a second pressure transmitter PT2 (12), a third solenoid valve 7YV (13), a third unloading valve (23), a fourth solenoid valve 8YV (14), a fourth unloading valve (24), a third throttle hole (25) and a fourth throttle hole (26); the system safety oil circuit (15) is provided with a first throttle hole (18), a first pressure switch PS1 (1), a second pressure switch PS2 (2), a third pressure switch PS3 (3), a third pressure switch PS4 (4), a third pressure switch PS5 (5), a third pressure switch PS6 (6), a third pressure switch PS7 (7), a third pressure switch PS8 (8), a third pressure switch PS9 (9), a third pressure switch PS10 (11), a second pressure switch PS11 (2), a third pressure switch PS12 (2), a third pressure switch PS13 (13), a third pressure switch PS14 (24), a third pressure switch PS15 (25), a third pressure switch PS16 (26), a third pressure switch PS17 (13), a third pressure switch PS18 (26), a third pressure switch PS19 (26), a third pressure switch PS21 (26), a third pressure switch PS22 (26), a third pressure switch PS23 (26), a third pressure switch PS24 (26), a third pressure switch PS25 (26), a third pressure switch PS26 (26), a third pressure switch PS27 (13), a third pressure switch PS28 (26), a third pressure switch PS29 ... The analog safety oil circuit (20) is provided with a second throttle hole (19), a manual stop valve (17), a second pressure gauge (5), a first pressure transmitter PT1 (6), a pilot solenoid valve 4YV (7), an isolation valve (16), a first travel switch ZS6 (8) and a second travel switch ZS7 (9); the pilot solenoid valve 4YV (7) is connected to the isolation valve (16); the isolation valve (16) is connected to the first travel switch ZS6 (8) and the second travel switch ZS7 (9); the first travel switch ZS6 (8), the second travel switch ZS7 (9) are connected to the isolation valve (16 ... The signal of the travel switch ZS7 (9) is used by the DEH to judge the state of the isolation valve; the manual stop valve (17) is used to cut off the simulated safety oil when a fault is processed online; the first solenoid valve 5YV (10), the first unloading valve (21) and the third solenoid valve 7YV (13), the third unloading valve (23) are connected in parallel in the isolation module, and the second solenoid valve 6YV (11), the second unloading valve (22) and the fourth solenoid valve 8YV (14), the fourth unloading valve (24) are connected in parallel in the oil circuit; the third throttle hole (25), the second pressure transmitter PT2 (12) and the fourth throttle hole (26) are arranged in the series oil circuit.

2. A steam turbine high-pressure tripping device with isolation test and online maintenance functions as claimed in claim 1, characterized in that: Also includes DEH and ETS control systems.

3. A steam turbine high-pressure tripping device with isolation test and online maintenance functions as claimed in claim 1, characterized in that: The first pressure switch PS1 (1), the second pressure switch PS2 (2), and the third pressure switch PS3 (3) are independent sampling pressure switches divided into three positions according to 25 countermeasures.

4. A steam turbine high-pressure tripping device with isolation test and online maintenance functions as claimed in claim 1, characterized in that: The simulated safety oil circuit (20) generates simulated safety oil through the pilot solenoid valve 4YV (7) and the isolation valve (16).

5. A steam turbine high-pressure tripping device with isolation test and online maintenance functions as claimed in claim 1, characterized in that: The simulated safety oil circuit (20) generates simulated safety oil through the pilot solenoid valve 4YV (7) and the isolation valve (16).

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