CN212428961U

CN212428961U - Emergency trip control mechanism of DEH system

Info

Publication number: CN212428961U
Application number: CN202020369365.2U
Authority: CN
Inventors: 林永泽; 韩冰; 励之渊; 谢林奇; 陈子翀
Original assignee: Ningbo Chuangli Hydraulic Machinery Manufacturing Co ltd
Current assignee: Ningbo Chuangli Hydraulic Machinery Manufacturing Co ltd
Priority date: 2020-03-20
Filing date: 2020-03-20
Publication date: 2021-01-29
Anticipated expiration: 2030-03-20

Abstract

The DEH system emergency trip control mechanism is used for enabling the adjusting valve servomotor to respond to the conduction of the overspeed protection control oil way and the non-pressure oil return oil way to act so as to close the adjusting valve and/or enabling the main valve servomotor to respond to the conduction of the automatic stop emergency trip oil way and the non-pressure oil return oil way to act so as to close the main valve; the hydraulic reversing valve comprises a hydraulic reversing valve and a sequence valve, wherein an oil inlet and an oil return port of the hydraulic reversing valve are respectively communicated with a pressure oil path and a non-pressure oil return oil path, and an oil outlet of the hydraulic reversing valve can be communicated with an automatic shutdown emergency shut-off oil path and/or an overspeed protection control oil path; when the oil pressure of the pressure oil line is lower than the opening pressure of the sequence valve, the oil outlet and the oil return port of the hydraulic reversing valve are communicated, so that the automatic shutdown emergency shut-off oil line and/or the overspeed protection control oil line are communicated with the non-pressure oil return oil line. The utility model relates to a DEH system emergency interruption control mechanism can in time respond emergency interruption under the condition that has a power failure and mechanical overspeed protection became invalid, and the security is good, can realize emergency interruption's from control.

Description

Emergency trip control mechanism of DEH system

Technical Field

The utility model belongs to the technical field of the steam turbine technique and specifically relates to a DEH system emergency trip control mechanism is related to.

Background

The DEH System (Digital Electric hybrid Control System) is a short for a steam turbine Digital electro-Hydraulic Control System, is a professional Control means of a steam turbine generator, is a unique means for controlling the starting, stopping and rotating speed Control of a steam turbine and power Control, and is an indispensable Control device for realizing the functions of unit coordination Control, remote automatic scheduling and the like of a power plant. The DEH system consists of a computer control part (DEH control system) and a hydraulic actuator (EH system), wherein the DEH control system is a command center of the DEH system, and the EH system is an actuator system of the DEH system.

The EH system comprises an oil supply system, an actuating mechanism and a critical interruption system, wherein the oil supply system is used for providing high-pressure fire-resistant oil and driving the servo actuating mechanism by the high-pressure fire-resistant oil; the actuating mechanism responds to the electric command signal sent from the DEH control system to adjust the opening of each steam valve of the steam turbine; the critical interruption system is used for preventing a unit from generating a serious damage accident possibly caused by the abnormal work of part of equipment during the operation of the steam turbine, and when the steam turbine has a critical interruption condition (such as the rotating speed of 110 percent of rated rotating speed, low EH oil pressure, low lubricating oil pressure, low vacuum degree of a condenser, abrasion of a thrust bearing and the like), the critical interruption system needs to respond quickly to close all steam turbine inlet valves or close only a speed regulation steam valve, so that the operation protection of the steam turbine is realized.

The reliability of the critical interruption system directly affects the reliability of unit protection. At present, critical interruption systems are mainly divided into two cases: firstly, in order to prevent serious damage of a unit caused by abnormality of part of equipment in the operation of the unit, an automatic shutdown emergency shutdown system (AST for short) is arranged, and when abnormal conditions occur, all steam inlets are closed and the unit is immediately shut down; and an overspeed protection control system (OPC for short) temporarily closes the high-pressure regulating valve and the reheating regulating valve to reduce the air inflow and the power of the steam turbine, but cannot stop the steam turbine. Therefore, the unit is correspondingly provided with an automatic shutdown emergency shutoff oil way (AST oil way for short) and an overspeed protection control oil way (OPC oil way for short). The first is that a tripping electric signal of an emergency tripping control device (ETS for short) can enable an automatic shutdown emergency tripping electromagnetic valve (AST electromagnetic valve for short) to act, an AST oil way drains oil, all steam inlets are closed, and a unit is shut down; and the second is a mechanical overspeed and manual stop part, when the mechanical overspeed and manual stop part acts, an AST oil way can discharge oil through a diaphragm valve, all the steam inlets are closed, and the unit stops, so that an emergency protection effect is achieved.

An actuating mechanism in the EH system is a servomotor which mainly comprises a control block and a hydraulic cylinder. According to the type of the regulated steam valve, the servomotor is mainly divided into a main throttle valve, a high-pressure regulating valve, a medium-pressure main throttle valve and a medium-pressure regulating valve servomotor. The oil motors can be classified into a switching type and a control type according to the difference of the control blocks. The high-pressure regulating valve servomotor and the medium-pressure regulating valve servomotor both belong to a control type, and the control type servomotor enables the regulating valve to stay at any position through a servo valve in a control block; the high-pressure main throttle servomotor and the medium-pressure main throttle servomotor both belong to a switch type, and the switch type servomotor realizes full opening or full closing of the main throttle through an electromagnetic valve in a control block. Except that the control block can respond to an electric signal of the DEH control system to control the action of the piston of the hydraulic cylinder so as to adjust the opening degree of each steam valve of the steam turbine, the emergency shutoff system can drain hydraulic oil in an AST oil circuit or an OPC oil circuit so as to control the lifting of the piston in the hydraulic cylinder of the hydraulic servomotor, so that the valve rod is directly or indirectly driven to close the main throttle valve and adjust the throttle valve, and the emergency protection of the steam turbine is realized.

Because the hydraulic transmission system has certain internal leakage, the EH system has pressure loss which is not avoided. When the EH oil pressure is too low, the pushing effect on a piston in the hydraulic cylinder can be influenced, and the closing failure of the steam valve is easily caused, so that when the pressure switch on the pressure oil line detects the oil pressure of the EH system, the pressure switch sends a signal to the DEH control system, the DEH control system controls the AST electromagnetic valve to be electrified, the AST oil line is caused to discharge oil, all the steam inlet valves are closed, and the unit is stopped. The emergency trip control system and the manual shutdown and overspeed protection control system need power supply to operate. Once a power failure condition caused by weather reasons such as thunder and lightning occurs and the mechanical overspeed protection is blocked, the response of the emergency interruption system is not timely, the turbine overspeed is caused, and huge losses are caused to enterprises.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the first technical problem that a DEH system emergency trip control mechanism is provided to foretell technical current situation, can in time respond under the condition that has a power failure and mechanical overspeed protection became invalid, promote the security of turboset.

The utility model aims to solve the second technical problem that provide a DEH system emergency trip control mechanism to foretell technical current situation, need not artificial intervention and sensor feedback, can realize emergency trip's from control, make control signal transmission more reliable, the operation is difficult to make mistakes.

The utility model aims to solve the third technical problem that to foretell technical current situation and provide a DEH system emergency interruption control mechanism, can delay the impact that hydraulic oil produced when the inside switching-over of switching-over valve, make hydraulic system operation more stable.

The utility model provides a technical scheme that above-mentioned technical problem adopted does: the DEH system emergency trip control mechanism is used for enabling the throttle servomotor to respond to the conduction of the overspeed protection control oil path and the non-pressure oil return oil path to act so as to close the throttle and/or enabling the main throttle servomotor to respond to the conduction of the automatic stop emergency trip oil path and the non-pressure oil return oil path to act so as to close the main throttle;

the method is characterized in that: the hydraulic reversing valve is provided with an oil inlet, an oil outlet, an oil return port and a control port, the oil inlet of the hydraulic reversing valve is communicated with a pressure oil path, the oil outlet of the hydraulic reversing valve can be communicated with an automatic shutdown emergency shut-off oil path and/or an overspeed protection control oil path, and the oil return port of the hydraulic reversing valve is communicated with an oil return non-pressure oil path;

the sequence valve is provided with an oil inlet and an oil outlet, the oil inlet of the sequence valve is communicated with the pressure oil way, one path of a control port of the hydraulic reversing valve is communicated with the oil outlet of the sequence valve, and the other path of the control port of the hydraulic reversing valve is communicated with the non-pressure oil return oil way;

the pressure of the pressure oil path reaches the opening pressure state of the sequence valve, an oil inlet and an oil outlet of the hydraulic reversing valve are communicated, so that the automatic shutdown emergency trip oil path and the overspeed protection control oil path are both blocked by the non-pressure oil return oil path, the pressure of the pressure oil path is lower than that of the sequence valve, the oil outlet and an oil return port of the hydraulic reversing valve are communicated, and the automatic shutdown emergency trip oil path and/or the overspeed protection control oil path are/is communicated with the non-pressure oil return oil path.

In order to enable hydraulic oil in the automatic shutdown emergency interruption oil line and/or the overspeed protection control oil line to be quickly discharged during emergency interruption, a cartridge valve is arranged between an oil outlet of the hydraulic reversing valve and the automatic shutdown emergency interruption oil line and/or the overspeed protection control oil line, the cartridge valve is provided with a control port, a first working oil port and a second working oil port, the control port of the cartridge valve can be communicated with the oil outlet of the hydraulic reversing valve, the first working oil port of the cartridge valve is communicated with the automatic shutdown emergency interruption oil line or the overspeed protection control oil line, and the second working port of the cartridge valve is communicated with the non-pressure oil return oil line.

The system is further designed to further comprise an automatic shutdown pressure oil way, a first throttle orifice plate and a second throttle orifice plate, wherein one end of the automatic shutdown pressure oil way is communicated with the automatic shutdown emergency shutoff oil way through the first throttle orifice plate, and the other end of the automatic shutdown pressure oil way is communicated with the non-pressure oil return oil way through the second throttle orifice plate; the cartridge valve includes first cartridge valve, second cartridge valve, third cartridge valve and fourth cartridge valve, just the control port homoenergetic of first cartridge valve, second cartridge valve, third cartridge valve and fourth cartridge valve the oil-out intercommunication of switching-over valve surges, the first working port of first cartridge valve and third cartridge valve all with auto-stop emergency shut-off oil circuit intercommunication, the first working port of second cartridge valve and fourth cartridge valve all passes through auto-stop pressure oil circuit with auto-stop emergency shut-off oil circuit intercommunication, the second working port of first cartridge valve and third cartridge valve all passes through auto-stop pressure oil circuit with non-pressure oil return oil circuit intercommunication, the second working port of second cartridge valve and fourth cartridge valve all with non-pressure oil return oil circuit intercommunication. The first cartridge valve, the second cartridge valve, the third cartridge valve and the fourth cartridge valve are arranged in series-parallel connection, the first cartridge valve and the third cartridge valve are in a group, the second cartridge valve and the fourth cartridge valve are in a group, when the oil pressure of a control port of at least one cartridge valve in the group is 0, the automatic shutdown emergency shut-off oil way can be communicated with the non-pressure oil return oil way, and an automatic shutdown pressure oil way is arranged, so that the safety of the shut-off system is higher.

In a further design, the cartridge valves comprise a fifth cartridge valve and a sixth cartridge valve which are arranged in parallel, control ports of the fifth cartridge valve and the sixth cartridge valve can be communicated with an oil outlet of the hydraulic reversing valve, first working ports of the fifth cartridge valve and the sixth cartridge valve are communicated with the overspeed protection control oil way, and second working ports of the fifth cartridge valve and the sixth cartridge valve are communicated with the non-pressure oil return oil way. Through the fifth cartridge valve and the sixth cartridge valve which are arranged in parallel, when the oil pressure of the control port of at least one cartridge valve in the fifth cartridge valve and the sixth cartridge valve is 0, the overspeed protection control oil way can be communicated with the non-pressure oil return oil way, and the safety of the interruption system is higher.

In a further design, an electromagnetic valve is arranged between the oil outlet of the hydraulic reversing valve and the control port of the cartridge valve, and the electromagnetic valve is used for controlling whether the control port of the cartridge valve is communicated with the oil outlet of the hydraulic reversing valve or not.

In a further design, an electromagnetic valve is arranged between the oil outlet of the hydraulic reversing valve and the overspeed protection control oil path, and the electromagnetic valve is used for controlling whether the overspeed protection control oil path is communicated with the oil outlet of the hydraulic reversing valve or not.

The electromagnetic valve needs to have the on-off function, so that a two-position two-way reversing valve can be adopted, and a two-position three-way reversing valve commonly used in a DEH system can also be adopted.

In order to further improve the safety of the critical interruption system, the number of the electromagnetic valves is at least two, and at least two electromagnetic valves are arranged in series or in parallel. The on-off rules of the electromagnetic valves can be the same or different.

And a first damper for controlling the reset time of the hydraulic reversing valve is arranged between the control port of the hydraulic reversing valve and the non-pressure oil return oil way.

And a second damper is arranged between the pressure oil way and the oil inlet of the hydraulic reversing valve.

The arrangement of the first damper and the second damper can protect the hydraulic reversing valve and the control loop.

In order to enable the main throttle valve not to be influenced when the adjusting throttle valve is closed, two check valves are arranged between the automatic shutdown emergency interceptor oil way and the overspeed protection control oil way and are arranged in parallel, inlets of the two check valves are communicated with the overspeed protection control oil way, outlets of the two check valves are communicated with the automatic shutdown emergency interceptor oil way, and therefore the overspeed protection control oil way can be communicated with the non-pressure oil return oil way through the automatic shutdown emergency interceptor oil way.

Compared with the prior art, the utility model has the advantages of: the automatic shutdown emergency shutoff oil circuit and/or the overspeed protection control oil circuit are controlled to be communicated with the non-pressure oil return oil circuit by combining the sequence valve and the hydraulic reversing valve, so that the emergency shutoff of the DEH system can respond timely under the conditions of power failure and mechanical overspeed protection failure, the safety of a steam turbine unit is improved, and compared with the automatic shutdown emergency shutoff system and the overspeed protection control system which need to be combined with an external controller, the emergency shutoff of the DEH system does not need manual intervention and sensor feedback, the automatic control of the emergency shutoff can be realized, the control signal transmission is more reliable, the operation is not easy to make mistakes, the impact effect generated when hydraulic oil is reversed inside the reversing valve can be delayed, and the hydraulic system is more stable in operation.

Drawings

Fig. 1 is a schematic connection diagram of a DEH system emergency trip control mechanism in embodiment 1 of the present invention;

fig. 2 is a schematic connection diagram of a DEH system emergency trip control mechanism in embodiment 4 of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments.

Example 1

As shown in fig. 1, is a first preferred embodiment of the present invention.

As shown in fig. 1, the DEH system emergency trip control mechanism of the present embodiment is configured to operate the governor valve servomotor 92 to close the governor valve 102 in response to the communication between the overspeed protection control oil passage 14 and the non-pressure return oil passage 12, and to operate the main valve servomotor 91 to close the main valve 101 in response to the communication between the automatic stop emergency trip oil passage 13 and the non-pressure return oil passage 12.

As shown in fig. 1, two check valves 4 are arranged between the automatic shutdown emergency interruption oil line 13 and the overspeed protection control oil line 14, the two check valves 4 are arranged in parallel, inlets of the two check valves 4 are both communicated with the overspeed protection control oil line 14, outlets of the two check valves 4 are both communicated with the automatic shutdown emergency interruption oil line 13, so that the overspeed protection control oil line 14 can be communicated with the non-pressure oil return oil line 12 through the automatic shutdown emergency interruption oil line 13, that is, the automatic shutdown emergency interruption oil line 13 is communicated with the non-pressure oil return oil line 12 to control the main throttle servomotor 91 and the throttle servomotor 92 to operate.

As shown in fig. 1, the DEH system emergency trip control mechanism in this embodiment includes a hydraulic reversing valve 2 and a sequence valve 3, the hydraulic reversing valve 2 has an oil inlet, an oil outlet, an oil return port and a control port, the oil inlet of the hydraulic reversing valve 2 is communicated with a pressure oil path 11, one way of the oil outlet of the hydraulic reversing valve 2 can be communicated with an automatic shutdown emergency trip oil path 13, the other way can be communicated with an overspeed protection control oil path 14, and the oil return port of the hydraulic reversing valve 2 is communicated with a non-pressure oil return path 12. The sequence valve 3 is provided with an oil inlet and an oil outlet, the oil inlet of the sequence valve 3 is communicated with the pressure oil path 11, one path of a control port of the hydraulic reversing valve 2 is communicated with the oil outlet of the sequence valve 3, and the other path of the control port is communicated with the non-pressure oil return oil path 12. When the pressure of the pressure oil path 11 reaches the opening pressure of the sequence valve 3, the oil inlet and the oil outlet of the hydraulic reversing valve 2 are communicated, so that the automatic shutdown emergency shut-off oil path 13 and the overspeed protection control oil path 14 are both blocked from the non-pressure oil return oil path 12; when the pressure of the pressure oil path 11 is lower than the opening pressure of the sequence valve 2, the oil outlet and the oil return port of the hydraulic reversing valve 2 are communicated, so that the automatic shutdown emergency shut-off oil path 13 and the overspeed protection control oil path 14 can be communicated with the non-pressure oil return oil path 12.

In this embodiment, the sequence valve 3 and the hydraulic reversing valve 2 are combined to control the automatic shutdown emergency trip oil circuit 13 and the overspeed protection control oil circuit 14 to be communicated with the non-pressure oil return oil circuit 12, so that the emergency trip of the DEH system can respond in time under the conditions of power failure and mechanical overspeed protection failure, the safety of the steam turbine set is improved, and compared with an automatic shutdown emergency trip system and an overspeed protection control system which need to be combined with an external controller, the emergency trip of the DEH system does not need manual intervention and sensor feedback, the automatic control of emergency trip can be realized, the transmission of control signals is more reliable, the operation is not easy to make mistakes, the impact effect generated when hydraulic oil is reversed inside the reversing valve can be delayed, and the operation of the hydraulic system is more stable.

As shown in fig. 1, in order to quickly drain the hydraulic oil in the automatic shutdown emergency shutoff oil path 13 and the overspeed protection control oil path 14 at the time of emergency shutoff, cartridge valves having a control port, a first working oil port and a second working oil port are respectively disposed between the oil outlet of the hydraulic directional valve 2 and the automatic shutdown emergency shutoff oil path 13 and between the oil outlet of the hydraulic directional valve 2 and the overspeed protection control oil path 14. In order to ensure that the emergency shut-off system of the DEH system is safer, an electromagnetic valve is arranged between the oil outlet of the hydraulic reversing valve 2 and the control port of the cartridge valve and is used for controlling whether the control port of the cartridge valve is communicated with the oil outlet of the hydraulic reversing valve 2 or not.

Specifically, the DEH system emergency trip control mechanism in this embodiment further includes an automatic shutdown pressure oil path 15, a first orifice plate 51, and a second orifice plate 52, and one end of the automatic shutdown pressure oil path 15 is communicated with the automatic shutdown emergency trip oil path 13 through the first orifice plate 51, and the other end of the automatic shutdown pressure oil path 15 is communicated with the non-pressure oil return oil path 12 through the second orifice plate 52. The electromagnetic valves comprise a first electromagnetic valve 61, a second electromagnetic valve 62, a third electromagnetic valve 63 and a fourth electromagnetic valve 64 which are arranged in parallel, and oil inlets of the first electromagnetic valve 61, the second electromagnetic valve 62, the third electromagnetic valve 63 and the fourth electromagnetic valve 64 are communicated with an oil outlet of the hydraulic reversing valve 2. The cartridges include a first cartridge 71, a second cartridge 72, a third cartridge 73, and a fourth cartridge 74. Control ports of the first cartridge valve 71, the second cartridge valve 72, the third cartridge valve 73 and the fourth cartridge valve 74 are respectively communicated with oil outlets of the first electromagnetic valve 61, the second electromagnetic valve 62, the third electromagnetic valve 63 and the fourth electromagnetic valve 64, first working ports of the first cartridge valve 71 and the third cartridge valve 73 are respectively communicated with the automatic shutdown emergency shut-off oil passage 13, first working ports of the second cartridge valve 72 and the fourth cartridge valve 74 are respectively connected with the automatic shutdown emergency shut-off oil passage 13 through the automatic shutdown pressure oil passage 15, second working ports of the first cartridge valve 71 and the third cartridge valve 73 are respectively communicated with the non-pressure oil return passage 12 through the automatic shutdown pressure oil passage 15, and second working ports of the second cartridge valve 72 and the fourth cartridge valve 74 are respectively communicated with the non-pressure oil return passage 12.

In the present embodiment, the first cartridge valve 71, the second cartridge valve 72, the third cartridge valve 73, and the fourth cartridge valve 74 are arranged in series-parallel, so that the first cartridge valve 71 and the third cartridge valve 73 form one group, and the second cartridge valve 72 and the fourth cartridge valve 74 form one group, and when the control port oil pressure of at least one cartridge valve in the two groups is 0, the automatic-stop emergency shut-off oil passage 13 and the non-pressure oil return passage 12 can be communicated, and the automatic-stop pressure oil passage 15 and the first solenoid valve 61, the second solenoid valve 62, the third solenoid valve 63, and the fourth solenoid valve 64 are provided, so that the safety of the shut-off system is further improved.

As shown in fig. 1, the solenoid valve further includes a fifth solenoid valve 65 and a sixth solenoid valve 66 which are arranged in parallel, and oil inlets of the fifth solenoid valve 65 and the sixth solenoid valve 66 are both communicated with an oil outlet of the hydraulic reversing valve 2. The cartridge valve further comprises a fifth cartridge valve 75 and a sixth cartridge valve 76 which are arranged in parallel, control ports of the fifth cartridge valve 75 and the sixth cartridge valve 76 are respectively communicated with oil outlets of a fifth electromagnetic valve 65 and a sixth electromagnetic valve 66, first working ports of the fifth cartridge valve 75 and the sixth cartridge valve 76 are respectively communicated with an overspeed protection control oil path 14, and second working ports of the fifth cartridge valve 75 and the sixth cartridge valve 76 are respectively communicated with a non-pressure oil return path 12. By the fifth and

sixth cartridge valves

75 and 76 and the fifth and

sixth solenoid valves

65 and 66 provided in parallel, when the control port oil pressure of at least one of the fifth and

sixth cartridge valves

75 and 76 is set to 0, the overspeed protection control oil passage 14 can be communicated with the non-pressure return oil passage 12, and the safety of the shutoff system can be enhanced.

As shown in fig. 1, the solenoid valve in this embodiment is a two-position three-way reversing valve, and the solenoid valve has an oil inlet, an oil outlet, and an oil return port. Specifically, in an electrified state, oil inlets and oil outlets of the first electromagnetic valve 61, the second electromagnetic valve 62, the third electromagnetic valve 63 and the fourth electromagnetic valve 64 are communicated; under the condition that the first electromagnetic valve 61, the second electromagnetic valve 62, the third electromagnetic valve 63 and the fourth electromagnetic valve 64 are in a power-off state, oil inlets and oil outlets of the first electromagnetic valve 61, the second electromagnetic valve 62, the third electromagnetic valve 63 and the fourth electromagnetic valve 64 are communicated. Under the power-off state of the fifth electromagnetic valve 65 and the sixth electromagnetic valve 66, oil inlets and oil outlets of the fifth electromagnetic valve 65 and the sixth electromagnetic valve 66 are communicated; when the fifth solenoid valve 65 and the sixth solenoid valve 66 are powered on, oil inlets and oil outlets of the fifth solenoid valve 65 and the sixth solenoid valve 66 are communicated.

As shown in fig. 1, in order to protect the hydraulic directional control valve and the control circuit, a first damper 81 for controlling the reset time of the hydraulic directional control valve 2 is provided between the control port of the hydraulic directional control valve 2 and the non-pressure oil return path 12. And a second damper 82 is arranged between the oil inlet of the hydraulic reversing valve 2 and the pressure oil path 11.

As shown in fig. 1, the working principle of the DEH system emergency trip control mechanism of the present embodiment is as follows:

in a normal working condition, the oil pressure of the pressure oil path 11 is greater than the opening pressure of the sequence valve 3, so that the valve port of the sequence valve 3 is opened, hydraulic oil in the pressure oil path 11 enters the control port of the hydraulic reversing valve 2 to reverse the hydraulic reversing valve 2, and the oil inlet and the oil outlet of the hydraulic reversing valve 2 are communicated; at this time, the first solenoid valve 61, the second solenoid valve 62, the third solenoid valve 63, and the fourth solenoid valve 64 are in an energized state, and the fifth solenoid valve 65 and the sixth solenoid valve 66 are in a de-energized state; the hydraulic oil flowing out of the oil outlet of the hydraulic reversing valve 2 correspondingly enters the control ports of the first cartridge valve 71, the second cartridge valve 72, the third cartridge valve 73, the fourth cartridge valve 74, the fifth cartridge valve 75 and the sixth cartridge valve 76 through the first electromagnetic valve 61, the second electromagnetic valve 62, the third electromagnetic valve 63, the fourth electromagnetic valve 64, the fifth electromagnetic valve 65 and the sixth electromagnetic valve 66 respectively, so that the valve ports of the first cartridge valve 71, the second cartridge valve 72, the third cartridge valve 73, the fourth cartridge valve 74, the fifth cartridge valve 75 and the sixth cartridge valve 76 are closed, the automatic shutdown emergency shut-off oil path 13 and the non-pressure emergency control oil path 14 are blocked from the oil return oil path 12, and the steam turbine normally operates.

When the oil pressure of the pressure oil path 11 is reduced to be lower than the opening pressure of the sequence valve 3, the valve port of the sequence valve 3 is closed, hydraulic oil in the control port of the hydraulic reversing valve 2 enters the non-pressure oil return channel 12 through the first damper 81, so that the hydraulic reversing valve 2 is reset, and the oil outlet and the oil return port of the hydraulic reversing valve 2 are communicated; at this time, the first solenoid valve 61, the second solenoid valve 62, the third solenoid valve 63, and the fourth solenoid valve 64 are still in the energized state, and the fifth solenoid valve 65 and the sixth solenoid valve 66 are still in the de-energized state; the control ports of the first cartridge valve 71, the second cartridge valve 72, the third cartridge valve 73, the fourth cartridge valve 74, the fifth cartridge valve 75 and the sixth cartridge valve 76 are not fed with oil any more, so that the valve ports of the first cartridge valve 71, the second cartridge valve 72, the third cartridge valve 73, the fourth cartridge valve 74, the fifth cartridge valve 75 and the sixth cartridge valve 76 are all opened, the automatic shutdown emergency shut-off oil passage 13 is communicated with the automatic shutdown pressure oil passage 15 through the first cartridge valve 71 and the third cartridge valve 73, the automatic shutdown pressure oil passage 15 is communicated with the non-pressure oil return passage 12 through the second cartridge valve 72 and the fourth cartridge valve 74, the automatic shutdown emergency shut-off oil passage 13 is communicated with the non-pressure oil return passage 12, the overspeed protection control oil passage 14 is communicated with the non-pressure oil return passage 12 through the fifth cartridge valve 75 and the sixth cartridge valve 76, and the relief of the automatic shutdown emergency oil passage 13 and the overspeed protection control oil passage 14 is accordingly, and closing a main valve and an adjusting valve of the steam turbine.

Example 2

This example differs from example 1 in that: the oil outlet of the hydraulic reversing valve 2 can only be communicated with the automatic shutdown emergency interceptor oil way 13, so that the reversing of the hydraulic reversing valve 2 can only conduct the automatic shutdown emergency interceptor oil way 13 and the non-pressure oil return oil way 12, and the overspeed protection control oil way 14 is conducted with the non-pressure oil return oil way 12 through the automatic shutdown emergency interceptor oil way 13.

Example 3

This example differs from example 1 in that: the oil outlet of the hydraulic reversing valve 2 can only be communicated with the overspeed protection control oil way 14, so that the reversing of the hydraulic reversing valve 2 can only realize the communication between the overspeed protection control oil way 14 and the non-pressure oil return oil way 12, and the DEH system emergency interruption control mechanism can only control and adjust the closing of a valve.

Example 4

As shown in fig. 2, it is a fourth preferred embodiment of the present invention.

As shown in fig. 2, the present embodiment is different from embodiment 3 in that: only an electromagnetic valve is arranged between the oil outlet of the hydraulic reversing valve 2 and the overspeed protection control oil way 14, and a cartridge valve is not arranged.

Specifically, a seventh solenoid valve 67 and an eighth solenoid valve 68 are arranged between the oil outlet of the hydraulic reversing valve 2 and the overspeed protection control oil path 14, the seventh solenoid valve 67 and the eighth solenoid valve 68 are arranged in series, the seventh solenoid valve 67 and the eighth solenoid valve 68 both have an oil inlet, an oil outlet, and an oil return port, the oil inlet of the seventh solenoid valve 67 is communicated with the oil outlet of the hydraulic reversing valve 2, the oil outlet of the seventh solenoid valve 67 is communicated with the oil inlet of the eighth solenoid valve 68, the oil outlet of the eighth solenoid valve 68 is communicated with the overspeed protection control oil path 14, and the oil return ports of the seventh solenoid valve 67 and the eighth solenoid valve 68 are communicated with the non-pressure oil return oil path 12.

Claims

The DEH system emergency interruption control mechanism is used for enabling the adjusting valve servomotor (92) to respond to the conduction of the overspeed protection control oil path (14) and the non-pressure oil return oil path (12) to act so as to close the adjusting valve (102) and/or enabling the main valve servomotor (91) to respond to the conduction of the automatic shutdown emergency interruption oil path (13) and the non-pressure oil return oil path (12) to act so as to close the main valve (101);

the method is characterized in that: the hydraulic reversing valve (2) is provided with an oil inlet, an oil outlet, an oil return port and a control port, the oil inlet of the hydraulic reversing valve (2) is communicated with a pressure oil path (11), the oil outlet of the hydraulic reversing valve (2) can be communicated with an automatic shutdown emergency shut-off oil path (13) and/or an overspeed protection control oil path (14), and the oil return port of the hydraulic reversing valve (2) is communicated with a non-pressure oil return oil path (12);

the sequence valve (3) is provided with an oil inlet and an oil outlet, the oil inlet of the sequence valve (3) is communicated with the pressure oil way (11), one path of a control port of the hydraulic reversing valve (2) is communicated with the oil outlet of the sequence valve (3), and the other path of the control port of the hydraulic reversing valve is communicated with the non-pressure oil return oil way (12);

the pressure of pressure oil circuit (11) reaches under the state of the opening pressure of sequence valve (3), the oil inlet and the oil-out of switching-over valve (2) that surges lead to, thereby make automatic shutdown emergency shut-off oil circuit (13) and overspeed protection control oil circuit (14) all with non-pressure oil return oil circuit (12) block, the pressure of pressure oil circuit (11) is less than under the state of the opening pressure of sequence valve (3), the oil-out and the oil return opening of switching-over valve (2) that surges lead to, thereby make automatic shutdown emergency shut-off oil circuit (13) and/or overspeed protection control oil circuit (14) with non-pressure oil return oil circuit (12) lead to.
2. The DEH system emergency trip control mechanism according to claim 1, wherein a cartridge valve is arranged between the oil outlet of the hydraulic reversing valve (2) and the automatic shutdown emergency trip oil circuit (13) and/or the overspeed protection control oil circuit (14), the cartridge valve is provided with a control port, a first working oil port and a second working oil port, the control port of the cartridge valve can be communicated with the oil outlet of the hydraulic reversing valve (2), the first working oil port of the cartridge valve is communicated with the automatic shutdown emergency trip oil circuit (13) or the overspeed protection control oil circuit (14), and the second working port of the cartridge valve is communicated with the non-pressure oil return oil circuit (12).
3. The DEH system emergency trip control mechanism according to claim 2, further comprising an automatic shutdown pressure oil path (15), a first orifice plate (51) and a second orifice plate (52), wherein one end of the automatic shutdown pressure oil path (15) is communicated with the automatic shutdown emergency trip oil path (13) through the first orifice plate (51), and the other end of the automatic shutdown pressure oil path (15) is communicated with the non-pressure oil return path (12) through the second orifice plate (52); the cartridge valves comprise a first cartridge valve (71), a second cartridge valve (72), a third cartridge valve (73) and a fourth cartridge valve (74), control ports of the first cartridge valve (71), the second cartridge valve (72), the third cartridge valve (73) and the fourth cartridge valve (74) can be communicated with an oil outlet of the hydraulic reversing valve (2), first working ports of the first cartridge valve (71) and the third cartridge valve (73) are communicated with the automatic shutdown critical interruption oil way (13), first working ports of the second cartridge valve (72) and the fourth cartridge valve (74) are communicated with the automatic shutdown critical interruption oil way (13) through the automatic shutdown pressure oil way (15), second working ports of the first cartridge valve (71) and the third cartridge valve (73) are communicated with the non-pressure oil way (12) through the automatic shutdown pressure oil way (15), and second working ports of the second cartridge valve (72) and the fourth cartridge valve (74) are communicated with the non-pressure oil return oil way (12).
4. The DEH system emergency trip control mechanism according to any one of claims 2 to 3, wherein the cartridge valve comprises a fifth cartridge valve (75) and a sixth cartridge valve (76) which are arranged in parallel, control ports of the fifth cartridge valve (75) and the sixth cartridge valve (76) can be communicated with an oil outlet of the hydraulic reversing valve (2), first working ports of the fifth cartridge valve (75) and the sixth cartridge valve (76) are communicated with the overspeed protection control oil path (14), and second working ports of the fifth cartridge valve (75) and the sixth cartridge valve (76) are communicated with the non-pressure oil return path (12).
5. The DEH system critical interruption control mechanism according to claim 2, characterized in that an electromagnetic valve is provided between the oil outlet of the hydraulically operated directional control valve (2) and the control port of the cartridge valve, and the electromagnetic valve is used to control whether the control port of the cartridge valve is conducted with the oil outlet of the hydraulically operated directional control valve (2).
6. The DEH system emergency trip control mechanism according to claim 1, wherein an electromagnetic valve is arranged between the oil outlet of the hydraulic reversing valve (2) and the overspeed protection control oil path (14), and the electromagnetic valve is used for controlling whether the overspeed protection control oil path (14) is communicated with the oil outlet of the hydraulic reversing valve (2).
7. The DEH system critical trip control mechanism according to any of the claims 5-6 wherein the number of solenoid valves is at least two and at least two solenoid valves are arranged in series or in parallel.
8. The DEH system emergency trip control mechanism according to claim 1 or 2 or 3 or 5 or 6, characterized in that a first damper (81) for controlling the reset time of the hydraulically operated directional control valve (2) is arranged between the control port of the hydraulically operated directional control valve (2) and the non-pressure oil return path (12).
9. The DEH system emergency trip control mechanism according to claim 1 or 2 or 3 or 5 or 6, characterized in that a second damper (82) is arranged between the pressure oil path (11) and the oil inlet of the hydraulic reversing valve (2).
10. The DEH system emergency trip control mechanism according to claim 1 or 2 or 3 or 5 or 6, wherein two check valves (4) are arranged between the automatic shutdown emergency trip oil circuit (13) and the overspeed protection control oil circuit (14), the two check valves (4) are arranged in parallel, inlets of the two check valves (4) are communicated with the overspeed protection control oil circuit (14), outlets of the two check valves (4) are communicated with the automatic shutdown emergency trip oil circuit (13), and the overspeed protection control oil circuit (14) is communicated with the non-pressure oil return circuit (12) through the automatic shutdown emergency trip oil circuit (13).