CN218300926U - Improved shielding and grounding device for water collecting pipe of large internal water-cooled generator - Google Patents

Abstract

A water collecting pipe shielding grounding improvement device of a large internal water-cooled generator. The grounding wires of all the catchment pipes need to be detached when the insulation of the catchment pipes is measured every time, particularly when a unit is started or stopped, the insulation resistance of a generator needs to be measured, and the grounding wires of the catchment pipes are extremely troublesome to detach and install, so that the working efficiency is influenced. The utility model discloses the constitution includes: ground resistance case (3), high voltage isolator (4), current detection device (5), broken string monitoring devices (2) and audible-visual annunciator (6), each way catchment pipe earthing terminal leads to through ground connection downlead (1) broken string monitoring devices, through broken string monitoring devices after assemble all the way be connected to high voltage isolator, high voltage isolator's output pass through current detection device connect to ground resistance case's earthing terminal. The utility model is used for large-scale interior cold-water generator catchment pipe shielding ground connection improves.

Description

Improved shielding and grounding device for water collecting pipe of large internal water-cooled generator

Technical Field

The utility model relates to a large-scale interior cold-water generator catchment pipe shielding ground connection improves device.

Background

The stator winding of the large-scale steam turbine generator usually adopts an underwater cooling mode. During operation, stator cooling water is injected from a water inlet main pipe at the top of a water collecting pipe at the excitation end of the generator and flows out of a water outlet main pipe at the top of a water collecting pipe at the steam end after flowing through a hollow conducting wire of a stator winding, so that cooling circulation of the stator winding of the generator is completed. Insulation plates and epoxy phenolic insulating sleeves are used between the generator water collecting pipe and the support, the water inlet and outlet header pipe and the sewage discharge pipe to realize insulation between the water collecting pipe and the base. During the operation of the generator, the water collecting pipe needs to be grounded at one point, mainly for the safety of personnel and equipment. The flange between the catchment pipe and the external water pipe is an insulation structure, the catchment pipe is close to the end part of the generator winding and a plurality of temperature measuring elements are laid around the catchment pipe, if the catchment pipe is not grounded, when a maintainer checks the abnormity of the temperature measuring point, once the winding end part is damaged or the insulation of the insulation water pipe is broken down, the catchment pipe is electrified, and the temperature measuring device are dangerous for the staff working on the temperature measuring loop. Therefore, in operation, a jumper wire is connected at the flange of the water collecting pipe and the external water pipe, the water collecting pipe is grounded through the jumper wire, and meanwhile, the grounding wire is broken, so that the operation of the water collecting pipe is influenced, the interference on the measurement of the water temperature of the winding is also caused, and the monitoring of whether the grounding wire is well grounded is also important; the steam end catchment pipe is grounded, the excitation end catchment pipe is grounded, the outlet box small catchment pipe is grounded, the steam end catchment pipe and the excitation end catchment pipe are respectively located at 12 m and 6 m of the steam turbine room, the preventive test of the large generator is to perform insulation tests including insulation resistance test, direct current withstand voltage test, alternating current withstand voltage test and the like according to related industrial standards, one of the conditions of the insulation tests is that the catchment pipe is qualified in resistance to ground, the catchment pipe grounding wire at each position is removed when the catchment pipe is measured in each time, particularly, when the unit is started and stopped, the insulation resistance of the generator must be measured, the assembly and disassembly of the catchment pipe grounding wire are extremely troublesome, the working efficiency is influenced, and when the number of removal times is large, the insulation pad at the connecting flange is easily damaged.

Disclosure of Invention

The utility model aims at providing a large-scale interior cold-water generator catchment pipe shielding ground connection improves device.

The above purpose is realized by the following technical scheme:

the utility model provides a large-scale cold-in-water generator catchment pipe shielding ground connection improves device, its constitution includes ground resistance case, high-pressure isolator, current detection device, broken string monitoring devices and audible-visual alarm, and each way catchment pipe earthing terminal leads to through ground connection downlead broken string monitoring devices, through broken string monitoring devices after assemble all the way be connected to high-pressure isolator, high-pressure isolator's output pass through current detection device connect to ground resistance case's earthing terminal.

The current detection device and the broken line monitoring device are respectively connected with the audible and visual alarm and the decentralized control system.

Has the advantages that:

1. the utility model discloses lead the catchment ground connection of everywhere to the ground resistance incasement through special ground connection downlead, the earth connection passes through isolator operation, can save manpower, material resources, also can be respectively to measuring vapour, encourage both ends catchment pipe and the little catchment pipe of outlet box to implement the insulation simultaneously; meanwhile, when the water collecting pipe is in operation and multipoint grounding occurs, large circulation current can be generated on a grounding wire of the water collecting pipe, the grounding wire can be blown by overlarge current, and detection is realized by additionally arranging a grounding current detection device, so that safe and stable operation of equipment is ensured.

2. The utility model discloses audible-visual annunciator mainly sends when unusual when broken string monitoring devices and current detection device, holds tightly, reminds patrolling and examining personnel on the spot to inspect.

Description of the drawings:

FIG. 1 is a schematic structural view of the present invention;

in the figure: 1. a down conductor; 2. a wire breakage monitoring device; 3. a grounding resistance box; 4. a high voltage isolation switch; 5. a current detection device; 6. an audible and visual alarm; 7. a distributed control system.

The specific implementation mode is as follows:

example 1:

the utility model provides a large-scale cold-in-water generator catchment pipe shielding ground connection improves device, its constitution includes ground resistance case 3, high-pressure isolator 4, current detection device 5, broken string monitoring devices 2 and audible-visual annunciator 6, and each way catchment pipe earthing end leads to through ground connection downlead 1 broken string monitoring devices, through broken string monitoring devices after assemble all the way be connected to high-pressure isolator, high-pressure isolator's output pass through current detection device connect to ground resistance case's earthing terminal.

Signals collected by the broken line monitoring device and the current detection device are electrically connected with a Distributed Control System (DCS), so that monitoring by operators is facilitated, abnormality is found in time, and the Distributed Control System (DCS) is a control system of the power system and belongs to the conventional prior art.

Example 2:

according to the improved shielding and grounding device of the water collecting pipe of the large-sized water-cooled generator in the embodiment 1, the current detection device and the broken wire monitoring device are respectively connected with the audible and visual alarm and the decentralized control system 7.

Claims (2)

1. The utility model provides a large-scale interior cold-water generator catchment pipe shielding ground connection improves device which characterized by: the high-voltage isolating switch comprises a ground resistance box, a high-voltage isolating switch, a current detection device, a broken line monitoring device and an audible and visual alarm, wherein each path of water collecting pipe grounding end is led to the broken line monitoring device through a grounding downlead, the broken line monitoring device is connected to the high-voltage isolating switch in a converging mode, and the output end of the high-voltage isolating switch is connected to the grounding end of the ground resistance box through the current detection device.

2. The improved shielding and grounding device for the water collection pipe of the large internal water-cooled generator as claimed in claim 1, wherein: the current detection device and the broken line monitoring device are respectively connected with the audible and visual alarm and the decentralized control system.

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