Accident pressure distribution device based on hydraulic system and control method

Abstract

The invention discloses an accident pressure distributing device based on a hydraulic system and a control method. The device comprises an accident pressure distributing valve, an accident shutdown electromagnetic valve and an accident shutdown hydraulic control valve. The emergency distributing valve comprises a first structure and a second structure; under normal working conditions, the main distributing valve is communicated with the servomotor through the two structures; when the unit is overspeed or the main distributing valve refuses to move, the hydraulic control valve is reversed due to accident shutdown, control oil is switched to two structure pilot ports, the valve core is quickly shifted, so that a pressure oil tank is directly connected into a servomotor closing cavity, the cavity is opened, oil is returned to an oil collecting groove, and a bypass of the main distributing valve and a guide vane are fully closed.

Description

Technical Field

[0001] This invention relates to the field of hydraulic system emergency pressure control technology, and in particular to an emergency pressure control device and control method based on a hydraulic system. Background Technology

[0002] During operation, when the turbine generator unit's speed exceeds the rated value and reaches 115% or more, the governor's main pressure distribution valve should immediately activate, closing the guide vanes via the relay to achieve shutdown. However, in actual operation, the main pressure distribution valve may fail to respond in time due to mechanical jamming, refusal to activate, or other malfunctions, causing the unit to continue accelerating, posing a significant safety hazard of runaway or even damage.

[0003] To address this situation, existing technologies typically employ a single emergency pressure regulating valve as a redundant actuator, but this structure has the following drawbacks: 1. Single valve core or single-sided valve core switching; if jammed, the entire valve will fail. 2. The control oil circuit is coupled with the main oil circuit. During the switching process, the residual pressure of the main pressure distribution valve will interfere with the action of the relay and prolong the closing time. Existing technology cannot achieve true “complete bypass” and ensure that the relay is fully closed when the main pressure regulating valve completely fails to operate. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides an emergency pressure distribution device and control method based on a hydraulic system, which achieves isolation between the control and the main oil circuit, and features rapid response and high reliability.

[0005] This invention provides an emergency pressure distribution device based on a hydraulic system, the specific technical solution of which is as follows: This includes emergency pressure regulating valves, emergency shutdown solenoid valves, and emergency shutdown hydraulic control valves; The emergency pressure regulating valve includes a first structure and a second structure; The oil inlet of the emergency shutdown solenoid valve is connected to the control oil source pipeline of the hydraulic system via the emergency shutdown hydraulic control valve; The oil inlet of the emergency shutdown hydraulic control valve is connected to the control oil source pipeline of the hydraulic system; The first working port of the emergency shutdown hydraulic control valve is connected to the left control chamber of the first structure and the right control chamber of the second structure, respectively; the second working port of the emergency shutdown hydraulic control valve is connected to the right control chamber of the first structure and the left control chamber of the second structure, respectively. The right working oil port of the first structure is connected to the open outlet of the main pressure regulating valve and also to the open chamber of the relay; the left working oil port of the first structure is directly connected to the oil collection tank. The right working oil port of the second structure is directly connected to the pressure oil tank and to the closing chamber of the relay; the left working oil port of the second structure is connected to the closing chamber return oil port of the main pressure regulating valve.

[0006] Furthermore, the first working port of the emergency shutdown solenoid valve is connected to the right control chamber of the emergency shutdown hydraulic control valve, and the second working port of the emergency shutdown solenoid valve is connected to the left control chamber of the emergency shutdown hydraulic control valve.

[0007] Furthermore, the right control chamber of the emergency shutdown hydraulic valve is connected to the mechanical overspeed protection pressure-holding oil pipe via the emergency shutdown solenoid valve.

[0008] Furthermore, a control valve is provided on the control oil source pipeline connecting the oil inlet of the emergency shutdown hydraulic control valve to the hydraulic system.

[0009] Furthermore, both the first structure and the second structure include: a housing, a valve core, an end cap, a spring, a valve seat, a control on / off valve core, and a control off valve core; The housing has a main valve chamber, and the valve core is placed in the main valve chamber; the housing also has an end cap, the spring is sleeved between the end of the valve core and the end cap, and the valve seat is fixed in the main valve chamber, forming a seal with the shoulder of the valve core; The control open / close valve core is located at the inlet of the control oil source pipeline connected to the main valve chamber on the housing, and the control close / close valve core is located at the return oil point of the start-up oil source pipeline connected to the main valve chamber on the housing; the pilot oil ports of both the control open / close valve core and the control close / close valve core are connected to the working oil port of the emergency shutdown hydraulic control valve.

[0010] Furthermore, the first structure and the second structure also include an indicator rod; One end of the indicator rod is connected to the valve core, and the other end extends through the end cap and out of the housing to indicate the position of the valve core.

[0011] Furthermore, the top of the housing is provided with a flange for connecting the housing to the main pressure regulating valve housing.

[0012] The present invention also discloses a control method based on the above-described emergency pressure distribution device, including normal operating condition control and emergency operating condition control; The normal operating condition control is as follows: S1: The lower half of the regulating emergency shutdown solenoid valve is connected; S2: Connect the right side of the hydraulic control valve for emergency shutdown; S3: The oil from the control pressure oil source pipeline is introduced into the left side of the first structure and the right side of the second structure respectively, pushing the corresponding control on / off valve core to open and the control off valve core to close. S4: The main pressure regulating valve of the speed controller is connected to the open chamber of the relay through the right side of the first structure; the open chamber of the relay is connected to the closed chamber of the main pressure regulating valve for oil return through the left side of the second structure; The specific details of the accident condition control are as follows: M1: Accident condition triggered; M2: The left side of the emergency shutdown hydraulic control valve is connected; M3: The oil in the control pressure oil source pipeline is respectively introduced into the left side of the first structure and the right side of the second structure; M4: The control valve core and the control valve core are switched, so that the valve core quickly changes direction under the action of spring and differential pressure. Then the right working oil port of the first structure is closed and the left working oil port of the second structure is closed. M5: The pressure oil tank is directly connected to the servo motor's closed chamber via the right side of the second structure, and the servo motor's open chamber returns oil directly to the oil collection tank via the left side of the first structure.

[0013] The beneficial effects of this invention are as follows: 1. In this invention, the control oil circuit and the main oil circuit are completely isolated by an emergency shutdown hydraulic control valve. During switching, the residual pressure of the main pressure regulating valve no longer interferes with the relay, shortening the closing time. The control on / off valve core is directly controlled by the emergency shutdown hydraulic control valve. The valve core can instantly switch direction under the action of spring and differential pressure, ensuring rapid response. This invention designs a left-right dual-structure emergency pressure regulating valve. When the valve core on one side is stuck, the other side can still complete the switching, ensuring the reliability of the device. The entire device can be connected to the existing main pressure regulating valve housing integrally or separately via flange, without modifying the relay and speed controller, facilitating on-site modification.

[0014] 2. In the event of an accident, the pressure oil tank is directly connected to the servo valve closing chamber via the right side of the second structure, while the servo valve returns oil via the left side of the first structure. The main pressure distribution valve is completely bypassed, ensuring that the guide vanes are fully closed. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the connection structure of the emergency pressure distribution device.

[0016] Figure 2 This is a schematic diagram of the left side of the emergency pressure regulating valve.

[0017] Figure 3 This is a schematic diagram of the right side of the emergency pressure regulating valve.

[0018] Figure 4 This is a schematic diagram of the control circuit for when the pressure regulating valve fails to operate under normal operating conditions.

[0019] Figure 5 This is a schematic diagram of the oil circuit for the control section of the pressure regulating valve under accident conditions.

[0020] Explanation of reference numerals in the attached diagram: 1-Emergency pressure regulating valve, 2-Emergency shutdown solenoid valve, 3-Emergency shutdown hydraulic control valve, 4-Control oil source pipeline, 5-Mechanical overspeed protection pressure holding oil pipeline, 6-Main pressure regulating valve, 7-Housing, 8-Valve core, 9-End cover, 10-Spring, 11-Valve seat, 12-Control on / off valve core, 13-Control off / close valve core, 14-Indicator rod, 15-Flange. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention are clearly and completely described in the following description. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] In the description of the embodiments of the present invention, it should be noted that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is conventionally placed during use, or the orientation or positional relationship in which those skilled in the art conventionally understand it during use. This is only for the convenience of describing the present invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention. Furthermore, the terms "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0024] Example 1 Embodiment 1 of the present invention discloses an emergency pressure distribution device based on a hydraulic system, such as... Figure 1 As shown, it includes an emergency pressure regulating valve, an emergency shutdown solenoid valve, and an emergency shutdown hydraulic control valve; The emergency pressure regulating valve includes a first structure and a second structure that are symmetrical from left to right; the first structure is the left structure of the emergency pressure regulating valve, and the second structure is the right structure of the emergency pressure regulating valve. The oil inlet of the emergency shutdown solenoid valve is connected to the control oil source pipeline of the hydraulic system via the emergency shutdown hydraulic control valve; Specifically, the oil inlet of the emergency shutdown hydraulic control valve is connected to the control oil source pipeline of the hydraulic system and is equipped with a control valve 1100-4.

[0025] The oil inlet of the emergency shutdown hydraulic control valve is connected to the control oil source pipeline of the hydraulic system via control valve 1100-4; The first working port of the emergency shutdown hydraulic control valve is connected to the left control chamber of the first structure and the right control chamber of the second structure, respectively; the second working port of the emergency shutdown hydraulic control valve is connected to the right control chamber of the first structure and the left control chamber of the second structure, respectively. The right working oil port of the first structure is connected to the open outlet of the main pressure regulating valve and also to the open chamber of the relay; the left working oil port of the first structure is directly connected to the oil collection tank. The right working oil port of the second structure is directly connected to the pressure oil tank and to the closing chamber of the relay; the left working oil port of the second structure is connected to the closing chamber return oil port of the main pressure regulating valve.

[0026] In a preferred embodiment, the first working port of the emergency shutdown solenoid valve is connected to the right control chamber of the emergency shutdown hydraulic control valve, and the second working port of the emergency shutdown solenoid valve is connected to the left control chamber of the emergency shutdown hydraulic control valve.

[0027] In a preferred embodiment, the right control chamber of the emergency shutdown hydraulic control valve is connected to the mechanical overspeed protection pressure-holding oil pipe via the emergency shutdown solenoid valve.

[0028] As a preferred embodiment, such as Figure 2 and Figure 3 As shown, both the first structure and the second structure include: a housing, a valve core, an end cap, a spring, an indicator rod, a flange, a valve seat, a control on / off valve core, and a control off valve core; The housing contains a main valve chamber, and the valve core is placed within the main valve chamber and can slide axially within it. An end cap is also provided on the outside of the housing, fixed to the outer end of the housing and sealing one end of the valve core. A spring is sleeved between the end of the valve core and the end cap to provide a restoring force to the valve core. One end of an indicator rod is connected to the valve core, and the other end extends through the end cap out of the housing to indicate the position of the valve core. The valve seat is fixed within the main valve chamber and forms a seal with the shoulder of the valve core. A flange is located on the top of the housing to connect the housing to the main pressure regulating valve housing; specifically, the housing and the main pressure regulating valve housing are connected integrally or separately via the flange.

[0029] The control open / close valve core is located at the inlet of the control oil source pipeline connected to the main valve chamber on the housing, and is used to control the on / off of the pressure oil entering one end of the valve core; the control close / close valve core is located at the return oil point of the open to oil source pipeline connected to the main valve chamber on the housing, and is used to control the on / off of the other end of the valve core to the oil collection tank; the pilot oil ports of both the control open / close valve core and the control close / close valve core are connected to the working oil port of the emergency shutdown hydraulic control valve.

[0030] Example 2 Embodiment 2 of the present invention discloses a control method based on the emergency pressure distribution device described in Embodiment 1, including normal operating condition control and emergency operating condition control; like Figure 4 As shown, the specific operation flow of the normal operating condition control is as follows: S1: The lower half of the regulating emergency shutdown solenoid valve is connected; S2: Adjust the right side of the emergency shutdown hydraulic control valve to connect, that is, the right control chamber of the emergency shutdown hydraulic control valve is always pressurized → the valve core remains in the right position; S3: The oil from the control pressure oil source pipeline is connected to the right side of the emergency shutdown hydraulic valve via control valve 1100-4, and simultaneously connected to the left pilot port of the first structure and the right pilot port of the second structure, pushing the corresponding control open valve core to open and the control close valve core to close, so that the control oil circuits at both ends of the valve core are connected to / closed in place with the system. S4: The governor's main pressure distribution valve is connected to the servo chamber through the right side of the first structure. The pressure oil passes through the governor's main pressure distribution valve opening outlet → the right working oil port of the first structure → the servo chamber. The relay chamber opens and returns oil through the left side of the second structure and the main pressure regulating valve; that is, the relay chamber closes → the left working oil port of the second structure → the main pressure regulating valve closes and returns oil → the oil collection tank.

[0031] Under normal operating conditions, the emergency pressure regulating valve serves only as a channel, while the main pressure regulating valve fully controls the relay.

[0032] like Figure 5 As shown, the specific operation flow for the accident condition control is as follows: M1: Accident condition triggered; Specifically, the accident triggering conditions include: The mechanical overspeed protection pressure holding oil pipe loses pressure, which in turn causes the right-side control chamber of the hydraulic valve to lose pressure; Or, direct electrical triggering may cause the upper part of the solenoid valve to shut down due to an accident, thereby pressurizing the control chamber on the left side of the hydraulic valve.

[0033] M2: The left side of the emergency shutdown hydraulic control valve is connected; M3: The oil from the control pressure oil source pipeline flows through the control valve 1100-4 to the left side of the emergency shutdown hydraulic control valve, and simultaneously enters the left pilot port of the first structure and the right pilot port of the second structure; M4: The control valve core and the control valve core are switched, so that the valve core quickly changes direction under the action of spring and differential pressure. Then the right working oil port of the first structure is closed and the left working oil port of the second structure is closed. Specifically, after the switch is completed, the main pressure regulating valve of the speed controller is bypassed, and the relay is no longer controlled by the main pressure regulating valve.

[0034] M5: The pressure oil tank is directly connected to the servo valve cavity via the right side of the second structure; The oil at the opening of the relay device returns directly to the oil collection tank via the left side of the first structure.

[0035] In the event of an accident, the main pressure distribution valve is bypassed, and the servo unit obtains the full differential pressure and immediately closes the guide vanes, thus achieving an emergency shutdown of the unit.

[0036] This invention is not limited to the specific embodiments described above. The invention extends to any new feature or combination disclosed in this specification, as well as any new method or process step or combination disclosed herein.

Claims

1. An emergency pressure distribution device based on a hydraulic system, characterized in that, This includes emergency pressure regulating valves, emergency shutdown solenoid valves, and emergency shutdown hydraulic control valves; The emergency pressure regulating valve includes a first structure and a second structure; The oil inlet of the emergency shutdown solenoid valve is connected to the control oil source pipeline of the hydraulic system via the emergency shutdown hydraulic control valve; The oil inlet of the emergency shutdown hydraulic control valve is connected to the control oil source pipeline of the hydraulic system; The first working port of the emergency shutdown hydraulic control valve is connected to the left control chamber of the first structure and the right control chamber of the second structure, respectively; the second working port of the emergency shutdown hydraulic control valve is connected to the right control chamber of the first structure and the left control chamber of the second structure, respectively. The right working oil port of the first structure is connected to the open outlet of the main pressure regulating valve and also to the open chamber of the relay; the left working oil port of the first structure is directly connected to the oil collection tank. The right working oil port of the second structure is directly connected to the pressure oil tank and to the closing chamber of the relay; the left working oil port of the second structure is connected to the closing chamber return oil port of the main pressure regulating valve.

2. The emergency pressure distribution device based on a hydraulic system according to claim 1, characterized in that, The first working port of the emergency shutdown solenoid valve is connected to the right control chamber of the emergency shutdown hydraulic control valve, and the second working port of the emergency shutdown solenoid valve is connected to the left control chamber of the emergency shutdown hydraulic control valve.

3. The emergency pressure distribution device based on a hydraulic system according to claim 2, characterized in that, The right control chamber of the emergency shutdown hydraulic valve is connected to the mechanical overspeed protection pressure-holding oil pipe via the emergency shutdown solenoid valve.

4. The emergency pressure distribution device based on a hydraulic system according to claim 1, characterized in that, The inlet of the emergency shutdown hydraulic control valve is connected to the control oil source pipeline of the hydraulic system, and a control valve is provided.

5. The emergency pressure distribution device based on a hydraulic system according to any one of claims 1-4, characterized in that, Both the first structure and the second structure include: a housing, a valve core, an end cap, a spring, a valve seat, a control on / off valve core, and a control off valve core; The housing has a main valve chamber, and the valve core is placed in the main valve chamber; the housing also has an end cap, the spring is sleeved between the end of the valve core and the end cap, and the valve seat is fixed in the main valve chamber, forming a seal with the shoulder of the valve core; The control open / close valve core is located at the inlet of the control oil source pipeline connected to the main valve chamber on the housing, and the control close / close valve core is located at the return oil point of the start-up oil source pipeline connected to the main valve chamber on the housing; the pilot oil ports of both the control open / close valve core and the control close / close valve core are connected to the working oil port of the emergency shutdown hydraulic control valve.

6. The emergency pressure distribution device based on a hydraulic system according to claim 5, characterized in that, The first structure and the second structure also include an indicator rod; One end of the indicator rod is connected to the valve core, and the other end extends out of the housing through the end cap.

7. The emergency pressure distribution device based on a hydraulic system according to claim 6, characterized in that, The top of the housing is also provided with a flange.

8. A control method, characterized in that, The emergency pressure distribution device according to any one of claims 1-6 includes normal operating condition control and emergency operating condition control; The normal operating condition control is as follows: S1: The lower half of the regulating emergency shutdown solenoid valve is connected; S2: Connect the right side of the hydraulic control valve for emergency shutdown; S3: The oil from the control pressure oil source pipeline is introduced into the left side of the first structure and the right side of the second structure respectively, pushing the corresponding control on / off valve core to open and the control off valve core to close. S4: The main pressure regulating valve of the speed controller is connected to the open chamber of the relay through the right side of the first structure; the open chamber of the relay is connected to the closed chamber of the main pressure regulating valve for oil return through the left side of the second structure; The specific details of the accident condition control are as follows: M1: Accident condition triggered; M2: The left side of the emergency shutdown hydraulic control valve is connected; M3: The oil in the control pressure oil source pipeline is respectively introduced into the left side of the first structure and the right side of the second structure; M4: The control valve core and the control valve core are switched, so that the valve core quickly changes direction under the action of spring and differential pressure. Then the right working oil port of the first structure is closed and the left working oil port of the second structure is closed. M5: The pressure oil tank is directly connected to the servo motor's closed chamber via the right side of the second structure, and the servo motor's open chamber returns oil directly to the oil collection tank via the left side of the first structure.

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