CN218883687U

CN218883687U - Multifunctional vacuum unit

Info

Publication number: CN218883687U
Application number: CN202222446876.1U
Authority: CN
Inventors: 宣歌伦; 毕烨; 厉汉宁; 汪丰
Original assignee: Hangzhou Kaierxuan Technology Co ltd
Current assignee: Hangzhou Kaierxuan Technology Co ltd
Priority date: 2022-09-09
Filing date: 2022-09-09
Publication date: 2023-04-18
Anticipated expiration: 2032-09-09

Abstract

The utility model relates to a multi-functional vacuum unit, this multi-functional vacuum unit have realized both can be to power transformer evacuation operation with the vacuum unit of same platform by preceding stage vacuum pump and lobe pump combination, also can be to GIS evacuation operation, characterized by: a set of backing vacuum pump (9) and a Roots pump (8) are used for being divided into two relatively independent pipelines through an electric three-way ball valve (6), one pipeline is a power transformer (16) vacuumizing pipeline, the other pipeline is a GIS (1) vacuumizing pipeline, when a channel between one pipeline and the backing vacuum pump (9) and the Roots pump (8) is automatically opened by rotating a selector switch, the other pipeline is automatically closed and isolated at the same time, the problem that two vacuum units respectively aim at the power transformer and the GIS to perform vacuumizing operation in the prior art is solved, the utilization rate of the vacuum units is improved, and the repeated investment fund of the vacuum units is saved.

Description

Multifunctional vacuum unit

1. Belongs to the technical field

The utility model relates to a multi-functional vacuum unit, this multi-functional vacuum unit have realized with the vacuum unit of same platform by preceding stage vacuum pump and lobe pump combination both can be to power transformer (hereinafter for short transformer) evacuation operation, also can be to the totally closed combined electrical apparatus of GIS gas insulation (hereinafter for short GIS) evacuation operation. The problem that two vacuum units combined by a backing vacuum pump and a roots pump respectively carry out vacuum pumping operation on electric equipment under two different working conditions in the past is solved, the utilization rate of the vacuum units is improved, and the repeated investment fund of the vacuum units is saved.

2. Background of the invention

At present, after a well-known transformer with the voltage of 110KV and above is installed, a tank needs to be vacuumized to remove moisture and air when transformer oil is injected, and the insulation property is enhanced. However, in the process of vacuum pumping, some transformer oil components are inevitably introduced into the transformer vacuum unit pipeline along with the pumped gas, so that an oil-gas separator is arranged in front of the transformer vacuum unit pipeline to reduce the transformer oil components entering the transformer vacuum unit pipeline as much as possible, but 100% of transformer oil components cannot be completely separated. In addition, GIS of 110KV and higher is a high-voltage composite apparatus using SF6 gas as an insulating medium, and has a high requirement for the purity of SF6 gas: wherein the water content is less than 40 μ L/L, and the oil content is less than 4 μ g/g. Therefore, the strict requirement that the pipeline does not contain moisture and oil is provided for the vacuum unit for vacuumizing operation before the GIS is filled with pure SF6 gas, and measures for preventing any oil from returning to the GIS pipeline in sudden power failure are provided. The existing processing method is to design two special vacuum units aiming at different working conditions of transformer vacuum pumping and GIS vacuum pumping, namely a transformer vacuum unit and a GIS vacuum unit, and the method has the following defects:

1. the core components of the vacuum unit are a backing vacuum pump and a roots pump, the cost of the backing vacuum pump and the roots pump accounts for about 70% of the cost price of the whole vacuum unit, and the core components (the backing vacuum pump and the roots pump) of the transformer vacuum unit and the GIS vacuum unit are identical, so that the condition of repeated investment can be caused

2. Generally, the annual use rate of each vacuum unit is about 30%, the idle time of the vacuum units is far longer than the use time, and the use rate of a single vacuum unit is very low.

3. Summary of the invention

In order to overcome the defects of the prior treatment method, the utility model provides a novel multifunctional vacuum unit, which is characterized in that: the same vacuum unit is suitable for both transformer vacuumizing and GIS vacuumizing, and simultaneously satisfies the vacuumizing operation of power equipment under two different working conditions.

The utility model provides a technical scheme is: a set of backing vacuum pump and roots pump are separated into two relatively independent pipelines through an electric three-way ball valve, one pipeline can be connected with a transformer through a flanged air pipe, and the pipelines are provided with a butterfly valve, an oil-gas separator, a liquid level switch, a ball valve, a vacuum gauge and the like. The other pipeline can be connected with the GIS by a gas pipe with a DN20 joint, and a vacuum solenoid valve, a vacuum gauge, a DN20 joint seat and the like are arranged in the pipeline. When the transformer needs to be vacuumized, the selection switch is rotated to select the transformer, the electric three-way ball valve automatically opens the passages of the transformer pipeline, the preceding stage vacuum pump and the roots pump, and simultaneously closes and isolates the GIS pipeline, so that a small amount of oil in the pipeline can be prevented from entering the GIS pipeline when the transformer is vacuumized, and meanwhile, a vacuum electromagnetic valve arranged in the GIS pipeline is also in a closed state, thereby playing a role in double protection. When the GIS is required to be vacuumized, the selection switch is rotated to select the GIS, the electric three-way ball valve automatically opens the passages of the GIS pipeline, the backing vacuum pump and the roots pump, and closes and isolates the transformer pipeline, and the vacuum electromagnetic valve in the GIS pipeline is in a closed state, so that any oil component can not enter the GIS pipeline before the backing vacuum pump is started to vacuumize. For the sake of safety, the vacuum solenoid valve is automatically opened after the pre-vacuum pump is started for 10 seconds (at the moment, the channel at the electric three-way ball valve is in a vacuum state), and the possibility that a small amount of oil possibly existing at the electric three-way ball valve enters the GIS pipeline can be eliminated due to the pressure difference. When power is suddenly cut off in the vacuum pumping process, the vacuum electromagnetic valve and the preceding-stage vacuum pump are synchronously closed and stopped, and any oil component is prevented from returning to enter the GIS pipeline.

The utility model has the advantages that: the multifunctional vacuum unit is used for safely and reliably realizing the vacuum pumping operation for the transformer and the vacuum pumping operation for the GIS, so that the repeated investment fund of the vacuum unit is greatly saved by more than 70%, and the utilization rate of the vacuum unit is greatly improved by almost 100%.

4. Description of the drawings

The present invention will be further explained with reference to the accompanying drawings:

fig. 1 is a flow chart of the operation of the multifunctional vacuum unit.

In the figure, 1.GIS, 2.A gas pipe with a DN20 joint, 3.DN20 joint seats, 4.GIS vacuum gauges, 5.vacuum electromagnetic valves, 6.electric three-way ball valves, 7.a transformer vacuum gauge, 8.a roots pump, 9.a preceding stage vacuum pump, 10, an atmosphere ball valve, 11.an oil-gas separator, 12.a liquid level switch, 13.an oil drain ball valve, 14.a butterfly valve, 15.a gas pipe with a flange and 16.a power transformer are arranged.

5. Detailed description of the preferred embodiments

As shown in fig. 1, when the selection switch selects the GIS (1) to pump vacuum, the electric three-way ball valve (6) automatically opens the passage between the GIS side pipeline and the roots pump (8) and the backing vacuum pump (9), and simultaneously automatically closes the pipeline on the side of the isolation power transformer. Connect DN20 joint socket (3) on GIS (1) and the vacuum unit with taking DN20 trachea (2), delay 10 seconds vacuum solenoid valve (5) and open after starting preceding stage vacuum pump (9), when GIS vacuum gauge (4) shows that vacuum degree reaches 3000Pa, lobe pump (8) automatic start evacuation, stop preceding stage vacuum pump (9) and finish GIS (1) evacuation operation after reaching the ultimate vacuum, at this moment lobe pump (8) and vacuum solenoid valve (5) synchronous stop and close.

As shown in figure 1, when the power transformer (16) is selected to be vacuumized by the selector switch, the electric three-way ball valve (6) automatically opens a channel between a power transformer side pipeline and the roots pump (8) and the backing vacuum pump (9), and simultaneously closes a pipeline on the isolated GIS side. A power transformer (16) and a butterfly valve (14) on a vacuum unit are connected through an air pipe (15) with a flange, a backing vacuum pump (9) is started to vacuumize after the butterfly valve (14) is opened, when a transformer vacuum gauge (7) displays that the vacuum degree reaches 3000Pa, a roots pump (8) is automatically started to vacuumize until the vacuum degree reaches a limit vacuum and the transformer oil injection is completed, the backing vacuum pump (9) is stopped to finish the vacuum pumping operation of the power transformer (16), and the butterfly valve (14) is closed. In the vacuumizing process, the oil separated by the oil-gas separator (11) is precipitated at the lower part of the oil-gas separator (11), when the oil level rises to a certain height, the liquid level switch (12) is triggered to send out an alarm sound for reminding, and the precipitated oil can be discharged by opening the oil discharge ball valve (13).

Claims

1. The utility model provides a multi-functional vacuum unit, this multi-functional vacuum unit has realized both can be to power transformer evacuation operation with the vacuum unit of same by preceding stage vacuum pump and lobe pump combination, also can be to GIS evacuation operation, characterized by: a set of backing vacuum pump (9) and a Roots pump (8) are used for being divided into two relatively independent pipelines through an electric three-way ball valve (6), one pipeline is a vacuum pumping pipeline of a power transformer (16), the other pipeline is a vacuum pumping pipeline of a GIS (1), and when a channel between one pipeline and the backing vacuum pump (9) and the Roots pump (8) is automatically opened by rotating a selection switch, the other pipeline is automatically closed and isolated at the same time.