CN202900331U

CN202900331U - Tripping protection system of steam turbine in emergency situations

Info

Publication number: CN202900331U
Application number: CN 201220520267
Authority: CN
Inventors: 沈翀; 王悦萍; 王春月
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-10-11
Filing date: 2012-10-11
Publication date: 2013-04-24
Anticipated expiration: 2022-10-11

Abstract

The utility model discloses a tripping protection system of a steam turbine in emergency situations and relates to the tripping protection system of the turbine. The tripping protection system of the steam turbine in the emergency situations solves the problem that the delay time of tripping commands sent from an emergency trip system (ETS) to all main throttle valves and control valves to execute action of closing is long. The tripping protection system of the steam turbine in the emergency situations comprises a turbine digital electrohydraulic control system, the turbine emergency trip system, a choosing two in three arithmetic circuit, three AST pressure switches and a hydraulic control system (EH system), and a tripping command signal transmission circuit and an or gate arithmetic circuit. Pressure sensitive components of the three AST pressure switches are respectively arranged in a working oil cavity of the EH system. Signal output ends of the three AST pressure switches are respectively connected with signal input ends of the choosing two in three arithmetic circuit. A signal input end of the tripping command signal transmission circuit is connected with the or gate arithmetic circuit. The choosing two in three arithmetic circuit is connected with the other signal input end of the or gate arithmetic circuit. The or gate arithmetic circuit is connected with a controlled signal input end of the turbine digital electrohydraulic control system.

Description

Turbine emergency situation trip protection system

Technical field

The utility model relates to steam turbine trip protection system; The improvement technology that belongs to the interlock of turbine emergency trip system and steam turbine electro-hydraulic governing system.

Background technique

The thermal power generation unit mainly comprises boiler, steam turbine, generator and some supplementary equipment; Its working principle is that the high temperature and high pressure steam that boiler produces enters steam turbine, makes its High Rotation Speed, and steam turbine drives the generator generating, and mechanical energy is converted into electric energy.During the steam turbine normal operation, high temperature, high pressure steam that boiler comes enter steam turbine by main inlet throttle-stop valve (containing high pressure main inlet throttle-stop valve and intermediate pressure main stop valve) and pitch (containing high-pressure governing valve and middle pressure pitch), and the adjustment of unit generation amount is controlled by the pitch aperture.The system of control main inlet throttle-stop valve and pitch is called as digital electro-hydraulic control system (DEH).Turbo-generator Set belongs to high temperature, high pressure and high-revolving equipment; the security of system protection is extremely important; be equipped with turbine emergency trip system (ETS system) for this reason; when the unit operation parameters such as unit vibration, swollen poor, rotating speed, lubrication pressure, EH oil pressure, vacuum do not meet the demands; the ETS system sends the chaser signal at once; make AST solenoid valve group 11 dead electricity; cause AST solenoid valve group 11 to open drainback passage, thereby EH system (hydraulic control system of main inlet throttle-stop valve and pitch) oil pressure is reduced.The reduction of oil pressure makes three AST pressure switch actions of installing on the EH oil pipe line, three contact point signals that the action of AST pressure switch produces enter the DEH system, the DEH system gets two to the contact point signal three that three AST pressure switch actions produce, then send the instruction of closing main inlet throttle-stop valve and pitch, and then closeall main inlet throttle-stop valve and pitch.In addition, when the EH system oil pressure was reduced to certain numerical value, main inlet throttle-stop valve and pitch also can be closed rapidly.Above-mentioned process is seen Fig. 1.

Find in the actual motion, when trip behavior appears in unit, send trip command from the ETS system and begin to begin to carry out the action of pass to all main inlet throttle-stop valves and pitch, time lag is larger, has exceeded safety specification.The analysis found that, main cause is that the DEH system does not send the instruction of closing main inlet throttle-stop valve and pitch when trip command is sent, all main inlet throttle-stop valves and pitch are realized by EH system oil pressure fast-descending fully, can find out that from the data of record the ETS system sends trip command to 11 actions of AST solenoid valve group, passed through 100 milliseconds time lag, the EH system oil pressure just can drop to the set point of AST pressure switch action, the delay that therefore causes main inlet throttle-stop valve and pitch to be closed.

The model utility content

The utility model has provided a kind of turbine emergency situation trip protection system, sends trip command from the ETS system and carries out to all main inlet throttle-stop valves and pitch and postpone large shortcoming the actuation time of closing thereby solved prior art.It comprises digital electro-hydraulic control system 1, turbine emergency trip system 2, three get two arithmetic circuits 3, the one AST pressure switch 4, the 2nd AST pressure switch 5, the 3rd AST pressure switch 6 and EH system 7, the one AST pressure switch 4, the pressure-sensing device of the 2nd AST pressure switch 5 and the 3rd AST pressure switch 6 is separately positioned in the system works oil pocket of EH system 7, the one AST pressure switch 4, the signal output part of the 2nd AST pressure switch 5 and the 3rd AST pressure switch 6 is connected to three signal input parts getting two arithmetic circuits 3, it also comprise trip command signal transfering circuit 8 and or door arithmetic circuit 9, the signal input part of trip command signal transfering circuit 8 connects on the trip command signal output part of turbine emergency trip system 2, the signal output part connection of trip command signal transfering circuit 8 or a signal input part of door arithmetic circuit 9, three get the signal output parts connection of two arithmetic circuits 3 or another signal input part of door arithmetic circuit 9, or the signal output part of door arithmetic circuit 9 connects the controlled signal input end of digital electro-hydraulic control system 1.

During work, when the unit operation parameters such as unit vibration, swollen poor, rotating speed, lubrication pressure, EH oil pressure, vacuum do not meet the demands, turbine emergency trip system 2 sends trip signal, the result that this trip signal and three is got two arithmetic circuits 3 carries out the computing of "or", export at last digital electro-hydraulic control system 1, carry out digital electro-hydraulic control.Because trip signal directly is applied to digital electro-hydraulic control system 1 by digital operation, avoided the delay of hydraulic system action, so corresponding tripping operation action can be made rapidly by system.

Description of drawings

Fig. 1 is the structural representation of background technique, and Fig. 2 is structural representation of the present utility model.

Embodiment

Embodiment one: specify present embodiment below in conjunction with Fig. 2.Present embodiment comprises that digital electro-hydraulic control system 1, turbine emergency trip system 2, three get two arithmetic circuits 3, an AST pressure switch 4, the 2nd AST pressure switch 5, the 3rd AST pressure switch 6 and EH system 7, the pressure-sensing device of the one AST pressure switch 4, the 2nd AST pressure switch 5 and the 3rd AST pressure switch 6 is separately positioned in the system works oil pocket of EH system 7, described system works oil pocket refers to the hydraulic oil pipeline between the hydraulic operation power unit and fuel feeding oil pump in the hydraulic pipe line of EH system, does not comprise return line; The general 12Mpa of the operating oil pressure of EH system; The signal output part of the one AST pressure switch 4, the 2nd AST pressure switch 5 and the 3rd AST pressure switch 6 is connected to three signal input parts getting two arithmetic circuits 3, and described three get two arithmetic circuits refers to get in three input signals two identical input signals as the circuit of Output rusults; Present embodiment also comprise trip command signal transfering circuit 8 and or door arithmetic circuit 9, the signal input part of trip command signal transfering circuit 8 connects on the trip command signal output part of turbine emergency trip system 2, the signal output part connection of trip command signal transfering circuit 8 or a signal input part of door arithmetic circuit 9, three signal output parts of getting two arithmetic circuits 3 connect or another signal input part of door arithmetic circuit 9, thereby or the signal output part of the door arithmetic circuit 9 controlled signal input end that connects digital electro-hydraulic control system 1 operation result of "or" is exported to the latter.

Embodiment two: specify present embodiment below in conjunction with Fig. 1 and Fig. 2.The difference of present embodiment and mode of execution one is also to have increased AST solenoid valve group 11, the controlled terminal of AST solenoid valve group 11 connects another trip signal output terminal of turbine emergency trip system 2, the oil-feed port of AST solenoid valve group 11 connects the system works oil pocket of EH system 7, and the fuel-displaced port of AST solenoid valve group 11 connects oil return fuel tank 12.So arrange, make trip signal can also control the reduction of EH system 7 pressurized oil systems, thereby also have the function of original turbine emergency situation trip protection system.

Claims

1. turbine emergency situation trip protection system; it comprises digital electro-hydraulic control system (1); turbine emergency trip system (2); three get two arithmetic circuits (3); the one AST pressure switch (4); the 2nd AST pressure switch (5); the 3rd AST pressure switch (6) and EH system (7); the one AST pressure switch (4); the pressure-sensing device of the 2nd AST pressure switch (5) and the 3rd AST pressure switch (6) is separately positioned in the system works oil pocket of EH system (7); the one AST pressure switch (4); the signal output part of the 2nd AST pressure switch (5) and the 3rd AST pressure switch (6) is connected to three signal input parts getting two arithmetic circuits (3); it is characterized in that it also comprise trip command signal transfering circuit (8) and or the door arithmetic circuit (9); the signal input part of trip command signal transfering circuit (8) connects on the trip command signal output part of turbine emergency trip system (2); the signal output part connection of trip command signal transfering circuit (8) or a signal input part of door arithmetic circuit (9); three get the signal output parts connection of two arithmetic circuits (3) or another signal input part of door arithmetic circuit (9), or the signal output part of door arithmetic circuit (9) connects the controlled signal input end of digital electro-hydraulic control system (1).

2. turbine emergency situation trip protection according to claim 1 system; it is characterized in that it also comprises AST solenoid valve group (11); the controlled terminal of AST solenoid valve group (11) connects another trip signal output terminal of turbine emergency trip system (2); the oil-feed port of AST solenoid valve group (11) connects the system works oil pocket of EH system (7), and the fuel-displaced port of AST solenoid valve group (11) connects oil return fuel tank (12).