阅读说明：本技术 一种发电机氢气系统事故保安装置及方法 (Generator hydrogen system accident safety device and method ) 是由 伍刚 牛坤 王涛 宋晓辉 刘岗 刘世雄 于 2021-01-28 设计创作，主要内容包括：一种发电机氢气系统事故保安装置及方法,包括密封油箱、氮气供气模块和发电机,密封油箱的出口与密封油泵入口相连接,密封油泵出口管道分为两路,一路依次经油氢差压阀、第二逆止门后接出两支管,通过密封油管道分别与发电机两侧密封油进口相连接；另一路依次经浮动油流量阀、第一逆止门后接出两道支管,通过浮动油管道分别与发电机的浮动油进口相连接；氮气供气模块出口与第一截止阀相连接,在第一截止阀后管道分为两路,一路与密封油管道相连接,一路与浮动油管道相连接；发电机充氢接口连接发电机氢气供气管道。本发明能够确保在密封油系统故障时,发电机内部氢气无法从发电机轴端泄露并与空气接触,避免事故发生。(An accident safety device and method for a generator hydrogen system comprises a sealed oil tank, a nitrogen gas supply module and a generator, wherein an outlet of the sealed oil tank is connected with an inlet of a sealed oil pump, an outlet pipeline of the sealed oil pump is divided into two paths, one path of the sealed oil pump is connected with two branch pipes after sequentially passing through an oil-hydrogen differential pressure valve and a second check valve, and the two branch pipes are respectively connected with sealed oil inlets at two sides of the generator through sealed oil pipelines; the other branch pipe is connected with two branch pipes after sequentially passing through a floating oil flow valve and a first check valve and is respectively connected with a floating oil inlet of the generator through a floating oil pipeline; the outlet of the nitrogen gas supply module is connected with a first stop valve, a pipeline is divided into two paths behind the first stop valve, one path is connected with the sealing oil pipeline, and the other path is connected with the floating oil pipeline; the generator hydrogen charging interface is connected with a generator hydrogen supply pipeline. The invention can ensure that hydrogen in the generator can not leak from the shaft end of the generator and contact with air when the sealing oil system fails, thereby avoiding accidents.)

1. An accident safety device for a generator hydrogen system is characterized by comprising a sealed oil tank (3), a nitrogen gas supply module (2) and a generator (1), wherein an outlet of the sealed oil tank (3) is connected with an inlet of a sealed oil pump (4), an outlet pipeline of the sealed oil pump (4) is divided into two paths, one path of the sealed oil pump sequentially passes through an oil-hydrogen differential pressure valve (7) and a second check valve (8) and then is connected with two branch pipes, and the two branch pipes are respectively connected with sealed oil inlets on two sides of the generator (1) through sealed oil pipelines (13);

the other branch is connected with two branch pipes after sequentially passing through a floating oil flow valve (5) and a first check valve (6) and is respectively connected with a floating oil inlet of the generator (1) through a floating oil pipeline (12);

the outlet of the nitrogen gas supply module (2) is connected with a first stop valve (9), a pipeline behind the first stop valve (9) is divided into two paths, one path is connected with a sealing oil pipeline (13), and the other path is connected with a floating oil pipeline (12);

the hydrogen charging interface of the generator (1) is connected with a hydrogen gas supply pipeline (14) of the generator.

2. Generator hydrogen system accident safety device according to claim 1, characterized by the fact that the floating oil enters from the generator (1) end, acting on the sealing shoe end face, and the sealing oil fills the generator sealing shoe radial gap after entering the generator (1).

3. The generator hydrogen system accident safety device according to claim 1, characterized in that the generator hydrogen supply pipeline (14) is connected with the generator (1) charging interface after passing through the second stop valve (10).

4. The generator hydrogen system accident safety device according to claim 3, characterized in that the hydrogen supply pipeline (14) behind the second stop valve (10) is provided with an interface connected with an accident discharge pipeline (15), and the accident discharge pipeline (15) is connected to an empty discharge main pipe of the unit hydrogen system.

5. Generator hydrogen system accident safety device according to claim 4, characterised in that the accident discharge conduit (15) is provided with a third shut-off valve (11).

6. The generator hydrogen system accident safety device according to claim 1, characterized in that a nitrogen gas supply pipeline (16) is arranged between the sealed oil pipeline (13) behind the second check valve (8) and the first check valve (9), and a nitrogen gas supply pipeline (16) is arranged between the floating oil pipeline (12) behind the first check valve (6) and the first check valve (9).

7. The generator hydrogen system accident safety device of claim 1, wherein the stop valves are pneumatic valves, driven by compressed air;

the nitrogen gas supply module (2) comprises a nitrogen gas bottle, a bus bar and a pressure reducing valve, and the nitrogen gas bottle is connected with the bus bar through a hose.

8. The use method of the generator hydrogen system accident safety device according to any one of claims 1 to 7, characterized by comprising the following steps;

after the oil-break fault occurs to the generator (1) sealed oil system, the first stop valve (9) is opened, nitrogen gas is provided by the nitrogen gas supply module (2) and is fed into the generator through the floating oil pipeline (12) and the sealed oil pipeline (13) by the nitrogen gas supply pipeline (16), the isolated air is contacted with the hydrogen, the first check valve (6) and the second check valve (8) prevent the nitrogen gas from flowing to the sealed oil tank (3), meanwhile, the second stop valve (10) is closed, the hydrogen is stopped to be supplemented to the inside of the generator, the third stop valve (11) is opened, the hydrogen inside the generator quickly passes through the accident discharge pipeline, the hydrogen flows into the air exhaust main pipe of the unit hydrogen system, and finally is discharged to the outside of the factory building.

9. Use method of the generator hydrogen system accident safety device according to claim 8, characterized in that the nitrogen pressure P provided by the nitrogen gas supply module (2)_NSpecific hydrogen rated pressure P of generator_HAbove 100kPa, i.e. P_N＝P_H+100kPa。

10. Use method of the generator hydrogen system accident safety device according to claim 8, characterized in that the nitrogen gas supply module (2) supplies nitrogen gas for a time period T_N≥10min。

Technical Field

The invention relates to the technical field of safe operation of power plants, in particular to an accident safety device and method for a hydrogen system of a generator.

Background

The large-scale unit generator usually adopts a water-hydrogen cooling mode, wherein components such as a generator rotor, a rotor winding and the like are cooled by taking hydrogen as a medium. Hydrogen in the generator is driven by the shaft end fan to circulate in the generator in a closed mode, and heat generated by acting is transferred to a cooling water system. The hydrogen is used as a cooling medium, the density is low, the ventilation loss of the generator can be reduced to the minimum, the efficiency of the generator is improved, the heat conductivity coefficient is high, and the cooling of the generator is favorably enhanced. However, there are some disadvantages, such as strong permeability of hydrogen, easy diffusion and leakage, and easy formation of explosive gas with air mixture, and the leakage may cause safety accidents such as explosion.

The sealing oil system is one of measures for limiting the outward leakage of hydrogen and is used for supplying oil to the generator sealing tile. The pressure of the sealing oil is controlled to be higher than the pressure of hydrogen in the generator by a certain value, so that the hydrogen in the generator is prevented from leaking outwards along a gap between the rotating shaft and the sealing tile.

In actual operation, if the sealed oil system breaks oil due to a fault, hydrogen can be leaked to the operation platform from the shaft end of the generator, the high probability of flammability and explosiveness is achieved, surrounding equipment is dense, the distance between the surrounding equipment and the centralized control room is short, and the risk of serious safety accidents is high.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a generator hydrogen system accident safety device and a generator hydrogen system accident safety method, which can ensure that hydrogen in a generator cannot leak from the shaft end of the generator and contact with air when a sealing oil system fails, so that accidents are avoided.

In order to achieve the purpose, the invention adopts the technical scheme that:

an accident safety device for a generator hydrogen system comprises a sealed oil tank 3, a nitrogen gas supply module 2 and a generator 1, wherein an outlet of the sealed oil tank 3 is connected with an inlet of a sealed oil pump 4, an outlet pipeline of the sealed oil pump 4 is divided into two paths, one path of the outlet pipeline is connected with two branch pipes after sequentially passing through an oil-hydrogen differential pressure valve 7 and a second check valve 8, and the two branch pipes are respectively connected with sealed oil inlets on two sides of the generator 1 through sealed oil pipelines 13;

the other branch is connected with two branch pipes after sequentially passing through a floating oil flow valve 5 and a first check valve 6 and is respectively connected with a floating oil inlet of the generator 1 through a floating oil pipeline 12;

the outlet of the nitrogen gas supply module 2 is connected with a first stop valve 9, a pipeline is divided into two paths behind the first stop valve 9, one path is connected with a sealing oil pipeline 13, and the other path is connected with a floating oil pipeline 12;

the hydrogen charging interface of the generator 1 is connected with a hydrogen gas supply pipeline 14 of the generator.

The floating oil enters from the end part of the generator 1 and acts on the end surface of the sealing tile, and the sealing oil fills the radial gap of the sealing tile of the generator after entering the generator 1.

The generator hydrogen gas supply pipeline 14 is connected with the generator 1 hydrogen charging interface after passing through the second stop valve 10.

The hydrogen gas supply pipeline 14 behind the second stop valve 10 is provided with an interface and is connected with an accident discharge pipeline 15, and the accident discharge pipeline 15 is connected to an air exhaust main pipe of a hydrogen system of the unit.

The accident discharging pipe 15 is provided with a third stop valve 11.

And a nitrogen gas supply pipeline 16 is arranged between the sealing oil pipeline 13 behind the second check valve 8 and the first check valve 9, and the nitrogen gas supply pipeline 16 is arranged between the floating oil pipeline 12 behind the first check valve 6 and the first check valve 9.

The stop valves are all pneumatic valves and are driven by compressed air.

The nitrogen gas supply module 2 comprises a nitrogen gas bottle, a busbar and a pressure reducing valve, and the nitrogen gas bottle is connected with the busbar through a hose.

The use method of the generator hydrogen system accident safety device comprises the following steps;

after the oil-break fault occurs in the sealed oil system of the generator 1, the first stop valve 9 is opened, the nitrogen gas supply module 2 supplies nitrogen gas to enter the generator through the floating oil pipeline 12 and the sealed oil pipeline 13 by the nitrogen gas supply pipeline 16, the isolated air is contacted with hydrogen gas, the first check valve 6 and the second check valve 8 prevent the nitrogen gas from flowing to the sealed oil tank 3, meanwhile, the second stop valve 10 is closed, the hydrogen gas is stopped from being supplemented to the inside of the generator, the third stop valve 11 is opened, the hydrogen gas in the generator quickly passes through the accident discharge pipeline, flows into the air discharge main pipe of the hydrogen system of the generator set, and is finally discharged to the outside of the factory building.

The nitrogen pressure P provided by the nitrogen gas supply module 2_NSpecific hydrogen rated pressure P of generator_HAbove 100kPa, i.e. P_N＝P_H+100kPa。

The nitrogen gas supply module 2 supplies nitrogen gas for a time period T_N≥10min。

The invention has the beneficial effects that:

the emergency safety device for the generator hydrogen system is characterized in that a spare nitrogen protection device is connected to a sealing oil system, so that when the sealing oil system is in oil failure, nitrogen can be rapidly supplemented to enter a sealing tile to isolate the contact of hydrogen and air, and meanwhile, the hydrogen in the generator is rapidly discharged out of a factory building, thereby avoiding safety accidents; the device has the characteristics of simple structure, high reliability and convenience in installation.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

The system comprises a generator 1, a nitrogen gas supply module 2, a sealed oil tank 3, a sealed oil pump 4, a floating oil flow valve 5, a first check valve 6, an oil-hydrogen differential pressure valve 7, a second check valve 8, a first check valve 9, a second check valve 10, a third check valve 11, a floating oil pipeline 12, a sealed oil pipeline 13, a hydrogen gas supply pipeline 14, an accident discharge pipeline 15 and a nitrogen gas supply pipeline 16.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1, the generator hydrogen system accident safety device according to the present invention includes a generator 1, a nitrogen gas supply module 2, a sealed oil tank 3, a sealed oil pump 4, a floating oil pipeline 12, a floating oil flow valve 5, a first check valve 6, a sealed oil pipeline 13, an oil-hydrogen differential pressure valve 7, a second check valve 8, a first check valve 9, a second check valve 10, and a third check valve 11;

the outlet of the sealed oil tank 3 is connected with the inlet of the sealed oil pump 4, the outlet pipeline of the sealed oil pump 4 is divided into two paths, and the two paths of outlet pipelines are connected with two branch pipes after sequentially passing through the oil-hydrogen differential pressure valve 7 and the second check valve 8 and are respectively connected with the sealed oil inlets at the two ends of the generator. After entering the generator 1, the sealing oil fills the radial gap of the generator sealing tile to prevent hydrogen from escaping. One branch pipe sequentially passes through the floating oil flow valve 5 and the first check valve 6 and then is connected with two branch pipes which are respectively connected with a floating oil inlet of the generator 1. The floating oil enters from the end part of the generator 1 and acts on the end surface of the sealing tile to counteract the axial thrust of hydrogen in the generator 1 to the sealing tile;

the outlet of the nitrogen gas supply module 2 is connected with a first stop valve 9, a pipeline behind the valve is divided into two paths, one path is connected with a sealing oil pipeline 13, and the other path is connected with a floating oil pipeline 12;

the generator hydrogen gas supply pipeline 14 is connected with the generator hydrogen charging interface after passing through the second stop valve 10. After passing through the second stop valve 10, the hydrogen supply pipeline 14 is provided with an interface and is connected with an accident discharge pipeline 15, and the accident discharge pipeline 15 is connected to an air discharge main pipe of a hydrogen system of the unit;

specifically, the interface of the nitrogen gas supply pipeline 16 and the sealing oil pipeline 13 is behind the second check valve 8, and the interface of the nitrogen gas supply pipeline 16 and the floating oil pipeline 12 is behind the first check valve 6; a third stop valve 11 is arranged on the accident discharge pipeline 15; the first stop valve 9, the second stop valve 10 and the third stop valve 11 are all pneumatic valves and are driven by compressed air; the nitrogen gas supply module 2 is composed of a nitrogen gas bottle, a bus bar and a pressure reducing valve, and the nitrogen gas bottle is connected with the bus bar through a hose.

The working principle of the invention is as follows:

after the sealing oil system breaks down and cuts off oil, the first stop valve 9 is opened, and nitrogen is suppliedThe gas module provides nitrogen gas to rapidly enter the generator through the sealing oil pipeline 13 and the floating oil pipeline 12, and airflow is formed around the sealing tile to prevent the hydrogen gas from flowing outwards. Meanwhile, the second stop valve 10 is closed, hydrogen supplement to the generator is stopped, and the third stop valve 11 is opened, so that hydrogen in the generator flows to the unit hydrogen air exhaust main pipe through the accident exhaust pipeline and is released to the atmosphere outside the plant. Wherein, the nitrogen pressure P provided by the nitrogen gas supply module_NSpecific hydrogen rated pressure P of generator_HAbove 100kPa, i.e. P_N＝P_H+100 kPa; time length T for nitrogen supply of nitrogen gas supply module_N≥10min。