JPH01289025A - Gas insulation bushing - Google Patents

Abstract

PURPOSE:To prevent the heat generated at a conductor of bushing from entering into a low temperature superconducting applied apparatus by providing a passage for a cooling medium in a conductor, and supporting the conductor by an insulator in which a passage for the cooling medium is provided, and connecting extermally a heat exchanger and a pump for the cooling medium by a cooling medium passage. CONSTITUTION:An insulative cooling medium is sealed in a circuit. The sealed cooling medium is caused to flow through a pipe line 15a by a pump 17 and passes through a inflow passage 18 in a boss 14 of a tank 13 and passes through a inflow passage 12 provided in a supporting insulator 10 and then reaches a conductor cooling medium passage 11 provided in a conductor 5. The Joule heat generated at the conductor 5 is taken away here by the insulative cooling medium to cool the conductor 5. After the insulative cooling medium circulate once the passage 11 in the conductor 5, it passes through the outflow passage 12' in the supporting insulator 10 and passes through the outflow passage 18' in the boss of the tank 13 and led outflow the bushing. Further, it enters a heat exchanger 16 via a pipe line 15b and gives heat outside and returns to pump 17 via a pipe line 15c.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to a gas-insulated air bushing used in an air extraction part of low-temperature superconducting applied equipment for power transmission systems.

(Prior Art) In recent years, the demand for energy in metropolitan areas and their surrounding areas has been increasing year by year.

To meet this demand, large thermal power plants near cities and nuclear power plants in remote areas are being built, and more are planned in the future. For the transmission of electrical energy from remote areas,
It is advantageous to transmit power at as high a voltage as possible in order to minimize transmission losses.

Currently, the maximum power transmission voltage in Japan is 550KV, and this voltage is used for long-distance power transmission. In the future, there are plans to further increase the transmission voltage to a 100 OKV transmission system.

On the other hand, high expectations are being placed on low-loss power transmission system systems that utilize superconducting technology, which has seen significant technological development in recent years, as an alternative method to increasing power transmission voltage and lowering power transmission losses.

Prototypes of superconducting transformers, superconducting generators, etc. using liquid helium (boiling point 4K) as a refrigerant have already been created and are on the verge of being put into practical use. Also.

Substances that exhibit superconductivity at temperatures above liquid nitrogen (boiling point 77K), which is lower than liquid helium, have also been discovered, and superconductivity at room temperature has already been discovered, which will lead to major developments in the field of energy transmission in the future. It is expected.

Although it will take a considerable amount of time to complete a superconducting power transmission system, it is believed that there are great benefits to reducing energy loss by making a single device, such as a transformer, superconducting. It will be done. It is thought that such superconducting applied equipment will be introduced into the current power transmission system as a low-loss alternative.

A bushing for air extraction as shown in FIG. 3 is usually used in the air extraction part of conventional power transmission equipment. That is, an insulator tube 4 filled with an insulating gas is attached to an insulator tube upper flange 3 and an insulator tube lower flange 6, and the insulator tube upper flange 3 is attached to the upper flange 2 via a backing so as to maintain gas-tightness. A terminal plate 1 for attaching a power transmission line for current flow and a conductor 5 for current flow are connected to the upper flange 2 at a position coaxial with the porcelain tube 4. The insulator lower flange 6 is attached to the lower flange 7 via a backing so as to maintain gas-tightness. Attached to the lower flange 7 are an internal shield 8 for alleviating the electric field located inside the insulator tube 4, and an air shield 9 for alleviating the electric field located in the air. Further, a gas tank 13 is attached to the side of the lower flange 7 opposite to the side on which the insulator tube 4 is attached via a backing so as to maintain gas tightness.

(Issue Ii that the invention seeks to solve) When connecting a superconducting power transmission and substation to a conventional system, it is necessary to provide a lead-out part to the atmosphere.

In low-temperature superconducting applied equipment, the intrusion of heat from the outside is considered to be a factor that greatly affects the performance of the equipment. Gas insulated bushings as explained in the previous section are used for the parts of conventional equipment that are drawn out into the air. In this case, the current flow generates Joule heat in the conductor 5 in the gas, heating the conductor and increasing its temperature. As a result, when such a conventional gas-insulated bushing is connected to low-temperature superconducting application equipment, the heat from the bushing conductor is transferred from the connection part by 1.
It is thought that it may enter the equipment and adversely affect the cooling performance and ultimately the performance of superconducting application equipment. Therefore, it is not possible to use such conventional gas insulating bushings.

The present invention provides a gas-insulated bushing for air extraction that prevents Joule heat generated in the conductor of the gas-insulated bushing from entering low-temperature superconducting applied equipment and does not reduce the performance of the low-temperature superconducting equipment. The purpose is to

[Structure of the invention]

(Means for solving the problem) In order to achieve the above purpose, that is, to suppress as much as possible the Joule heat generated in the conductor of the gas-insulated bushing from entering the inside of the low-temperature superconducting equipment, a cooling device is installed inside the conductor. A conductor is supported by an insulator provided with a refrigerant passage for circulating the refrigerant from the outside, and a refrigerant heat exchanger and a pump for refrigerant circulation are connected to the outside by the refrigerant flow path. It is characterized by the fact that

(Function) In the gas insulated bushing of the present invention, the insulating refrigerant is circulated through the cooling refrigerant passage provided inside the conductor by operating an external refrigerant circulation pump, and the insulating refrigerant is circulated through the cooling refrigerant passage provided inside the conductor. The generated Joule heat is absorbed by an insulating refrigerant to cool the conductor, and the heat is released to the outside of the bushing by an insulating refrigerant heat exchanger provided outside the bushing. In this way, it is possible to suppress the Joule heat generated in the conductor from entering the inside of the low-temperature superconducting device.

(Example) Next, an example of the gas insulating bushing of the present invention will be explained using FIG.

Note that the same parts as those in the prior art are given the same reference numerals and the description thereof will be omitted.

In FIG. 1, an insulating refrigerant channel 1 is connected to a bushing conductor 5
1 is provided, and this insulating refrigerant flow path 11 is configured to go around the inside of the conductor 5. Further, the insulating refrigerant flow path 1
1 has an inlet 19 and an outlet 19'.

The inlet 20 and the outlet 20' configured in the conductor 5
are formed in the support insulator 10, the inflow passage 12 and the outflow passage 1.
2', and is installed to prevent the insulating refrigerant from leaking to the outside. Further, a boss 14 having an inlet passage 18 and an outlet passage 18' is attached to the tank 13.
An inflow path 12 and an outflow path 1 formed in the support insulator 10
2' is connected to an inlet passage 18 and an outlet passage 18' formed in the boss 14 to prevent the insulating refrigerant from leaking to the outside. The support insulator 10 connects the conductor 5 to the tank 1.
3, and the conductor 5 is mechanically supported in the tank 13.
It is configured to be electrically insulated from the An inlet 20 and an outlet 20' are formed on the atmosphere side of the inlet passage 18 and the outlet passage 18' formed in the boss 14.

The inflow port 20 is connected to an externally provided pump F through a conduit 15a. In addition, the outlet 20'
is connected to a heat exchanger 16 provided outside by a pipe line tsb.

The pump 17 and the heat exchanger 16 are connected by a pipe line 15c. An insulating refrigerant is sealed, and the pump 17, the conductor 5. It is configured to circulate between the heat exchangers 16.

In this embodiment configured as described above, a flow path for cooling the conductor is provided in the bushing conductor, so that the flow path for cooling the conductor is used for the air extraction part of the low temperature superconducting equipment.

It is possible to create a gas-insulated bushing that suppresses the heat generated in the conductor from entering low-temperature superconducting equipment.

That is, an insulating refrigerant is sealed in the circulation path described in the section of the configuration description. The sealed insulating refrigerant flows through the conduit 15a by the pump 17.

It passes through the inlet passage 18 in the boss 14 of the tank 13 and passes through the inlet passage 12 of the support insulator 10 provided in the support insulator 10 .

The conductor refrigerant flow path 11 provided inside the conductor 5 is reached.

Here, the conductor 5 is cooled by absorbing Joule heat generated in the conductor 5 when current is applied by the insulating refrigerant circulating in the conductor refrigerant flow path 11. The insulating refrigerant goes around the conductor refrigerant flow path 11 in the conductor 5, and flows through the outflow path 12' in the support insulator lO.
It passes through the outflow passage 18' in the boss 14 of the tank 13 and is led to the outside of the bushing. Furthermore, the pipe line 15b
The heat exchanger 16 enters the heat exchanger 16 through the bushing conductor 5, where the heat taken away by the bushing conductor 5 is discharged to the outside, and returns to the pump 17 through the conduit 15c.

Arrows in the figure indicate the flow of the insulating refrigerant.

As described above, by circulating the insulating refrigerant inside the conductor from the outside of the bushing, it becomes possible to easily remove Joule heat generated during current flow from the conductor.

21st i! ! 1 shows another embodiment. In this embodiment, the conductor 5 is supported by a disc-shaped support insulator 10 instead of the support insulator in FIG. The channel 12 and the outlet channel 12' are provided in opposite directions. Further, a boss 14.14' having an inlet passage 18 and an outlet passage 18' is attached to the tank 13 so as to be connected to the inlet passage 12 and the outlet passage 12'. ing.

〔Effect of the invention〕

As explained above, according to the gas insulated bushing of the present invention, the bushing used for the air extraction part of low temperature superconducting equipment has a high performance that suppresses the intrusion of heat generated by current flow into the low temperature superconducting equipment. A gas insulating bushing for air extraction can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a gas insulating bushing according to the present invention, FIG. 2 is a sectional view of a gas insulating bushing according to another embodiment of the present invention, and FIG. 3 is a sectional view of a conventional gas insulating bushing. 1... Terminal board 2... Upper flange 3
... Insulator tube upper flange 4 ... Insulator tube 5 ... Conductor 6 ... Insulator pipe lower flange 7 ... Lower flange 8 ... Internal shield 9 ... Air shield 10 ... Support insulator 11 ...Conductor refrigerant flow path 12...Inflow path 12'...Outflow path 13...Tank 14...Boss
14・11. Boss 15a... conduit
15b...Pipeline 15c...Pipeline
16...Heat exchanger 17...Pump 1
8... Inflow channel 18'... Outflow channel 19.
...Inflow port (conductor) 19'...Outflow port (conductor)
20... Inflow port (boss) 20'... Outflow port (boss) Agent Patent attorney Noriyuki Chika Ken Yudo Daishimaru Ken Figure 2 Figure 3

Claims (1)

[Claims] In a gas insulated bushing, a central conductor is inserted coaxially with the insulating pipe into an insulating pipe filled with insulating gas.
The center conductor is provided with a flow path through which an insulating refrigerant flows, and the center conductor is further provided with an inlet and an outlet for the insulating refrigerant, and this connects the support insulator provided with the insulating refrigerant inlet and outlet path, and The supporting insulator is attached to the inlet and outlet of the conductor so as to connect the inlet and outlet passages of the supporting insulator, and the supporting insulator is attached to the lower part of the insulator tube on the opposite side of the connecting portion with the center conductor. an inflow path and an outflow path for the insulating refrigerant of the insulator, and an inflow path of the boss, which is provided in a tank provided with an insulating refrigerant inflow path and an outflow path;
The insulating refrigerant inlet and outlet are installed on the atmospheric side of the insulating refrigerant inlet and outlet of the boss, respectively, and the insulating refrigerant inlet and the outlet are connected to each other. It is connected to the pump by a pipe line, the outlet is connected to an external heat exchanger by a pipe line, the pump and the heat exchanger are connected by a pipe line, and all of these flow paths are insulated. A gas insulated bushing characterized by hermetically sealed refrigerant.