JPS62144309A - Gas insulating on-load tap changing transformer - Google Patents

Abstract

PURPOSE:To make compact the driving mechanism of the vacuum switch of a diverter switch DS and a tap selector TS and facilitate the inspection of an on-load tap changer LTC by making the gas pressure in a tap selector chamber higher than that in a diverter chamber. CONSTITUTION:Partition plates 9 are provided between a transformer body 3 and an LTC4 and between a DS6 and a TS7 whereby a gas is partitioned. The gas pressure in a TS chamber A is set higher than that in a DS chamber B. A tap winding and the TS7; the DS6 and the TS7 are respectively electrically connected to each other by connecting leads 8. Thus, since the gas pressure in the TS chamber A can be made higher, the TS7 can be made compact. Further, since the gas pressure in the DS chamber can be made lower, a vacuum switch driving mechanism can be made compact. When the DS6 is lifted and inspected, only the gas in the DS chamber B is required to be recovered and this, together with the low gas pressure, sharply reduces a gas recovery quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gas-insulated load tap change transformer (hereinafter abbreviated as LRT) using an insulating gas such as SF6 as an insulating medium.

[Conventional technology]

Demand for gas-insulated transformers to replace oil-immersed transformers is increasing year by year due to their advantages such as nonflammability and explosion-proofness. For gas-insulated LRT incorporating an on-load tap changer (hereinafter abbreviated as LTC), for example,
As mentioned in No. 5, the LTC is sometimes housed in a separate room from the transformer body to prevent dust, but the diverter switch (hereinafter referred to as DS) is a component of the LTC and cuts off the load current.
) and a tap selector (abbreviated as ) and tap selector (abbreviated as
(hereinafter abbreviated as TS) is generally housed in the same gas chamber as an oil-immersed transformer. For example, FIG. 3 is a drawing showing an example of the configuration of a conventional gas insulated LRT. tank 1
Inside the transformer body 3 and LTC 4 together with the insulating gas body 2
to store. The main body of the transformer consists of an iron core with nine windings, and the windings are provided with tap windings connected to the LTC4. LTC4 is a drive gear mechanism section 5. DS6. TS7
It consists of the main parts, and DS6 is a vacuum switch.

It consists of a resistor, vacuum switch drive mechanism, etc.

A connection lead 8 electrically connects the tap winding and TS7. Transformer body 3 and LTC 4 in tank 1
A partition plate 9 is provided between them to prevent metal powder generated from the LTC 4 from affecting the insulation of the transformer body.

[Problem that the invention seeks to solve]

With the above configuration, the following problem occurs because DS6 and TS7 of LTC4 have the same gas pressure. i.e. gas insulated LTC
A vacuum switch is generally used in the DS, but as the gas pressure increases, the gas replaces the spring resistance, so the mechanism that drives the vacuum switch must be enlarged.

In addition, the LTC needs to periodically lift and inspect the DS, which is the current interrupter, but for this purpose it is necessary to recover the gas, so as the gas pressure increases, the amount of gas to be recovered increases and the time required for inspection increases. The length will be longer, and larger equipment such as gas recovery equipment will be required. On the other hand, if the gas pressure is lowered, the dielectric strength of the insulating gas body will be lowered, so the insulation distance between the switching contacts of the TS must be increased, resulting in a larger TS.

The present invention has been made to eliminate the above-mentioned drawbacks, and D
It is an object of the present invention to provide a gas-insulated load tap change transformer that can make the drive mechanism of a vacuum switch S and a TS compact, and can also facilitate inspection of an LTC.

[Means for solving problems]

In order to achieve the above object, the present invention provides LTC DS and T
S is stored in a separate room, and the gas pressure in the TS chamber is made higher than the gas pressure in the DS chamber.

[Effect]

Since the gas pressure in the TS chamber is high, the dielectric strength is high, making it compact. Furthermore, the drive mechanism of the DS vacuum switch can also be made more compact because the gas pressure in the DS chamber is lowered. Furthermore, by separating the DS room and the TS room and lowering the gas pressure in the DS room, the amount of gas recovered when lifting the DS for inspection is significantly reduced, shortening inspection time and downsizing equipment such as gas recovery equipment. .

〔Example〕

Embodiments of the present invention will be described below with reference to FIG. The transformer body 3 and LT are placed inside the tank 1 along with the insulating gas body 2.
Store C4. The transformer main body 3 consists of an iron core and nine windings, and the windings are provided with tap windings connected to the LTC 4. LTC4 is a drive gear mechanism section 5. DS6.
It consists of the main parts of TS7, and DS6 consists of a vacuum switch, a resistor, and a vacuum switch drive mechanism. A partition plate 9 is provided between the transformer body 3 and the LTC 4 and between the DS6 and TS7 to separate the gas. The gas pressure in TS chamber A is DS
Set higher than the gas pressure in chamber B. Tap winding and T
S7 and DS6 and T S' 7 are electrically connected by connection leads 8.

In this way, the gas pressure in the TS chamber A can be increased, so that the TS 7 can be made compact.

Furthermore, since the gas pressure in the DS chamber B can be lowered, the vacuum switch drive mechanism can be made more compact. moreover,
Since DS chamber B is gas-separated, only the gas in DS chamber B needs to be recovered when lifting the DS6 for inspection, and in combination with the low gas pressure, this results in a significant reduction in the amount of gas recovered. This will reduce inspection time and downsize equipment such as gas recovery equipment.

2. The present invention is not limited to the above embodiments,
For example, as shown in FIG. 2, the same effect can be obtained even if the transformer main body 3 and the TS 7 are not separated into gas chambers but are shared in a common gas chamber.

〔Effect of the invention〕

As described above, according to the present invention, the DS and TS of the LTC are housed in separate rooms, and the gas pressure in the TS chamber is made higher than the gas pressure in the DS chamber, so that the LTC is a gas-insulated LRT that is compact and easy to inspect. can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of a gas insulated LRT according to the present invention, FIG. 2 is a sectional view showing the structure of another embodiment of the present invention,
FIG. 3 is a sectional view showing the structure of a conventional gas insulated LRT. 1...tank 2...insulating gas body 3...
Transformer body 4 LTC5 Drive gear mechanism 6 Diverter switch 7 Tap selector 8 Connection lead 9
Partition plate A...TS room B...DS room Agent Patent attorney Nori Chika Ken Yudo Hirofumi MitsumataFigure 1 Figure 2 Figure 3

Claims (2)

[Claims] (1) In a gas-insulated load tap changer in which the transformer main body and on-load tap changer are housed together with an insulating gas body in a tank, the diverter switch and tap selector of the on-load tap changer are housed in a separate room, and the tap changer is housed in a separate room. A gas-insulated load tap change transformer characterized in that the gas pressure in the selector chamber is higher than the gas pressure in the diverter switch chamber. (2) The gas-insulated load tap change transformer according to claim 1, wherein the tap selector is housed in a common gas chamber with the transformer main body.