JPH1041142A - Transformer with tap switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attach and detach a bushing and a bushing converter inside a tap switch box by providing a tap switch box with a bushing for drawing a lead wire of a wiring to an outside and providing a bushing converter to an inside of a tap switch box. SOLUTION: A bushing 7 and a bushing converter 12 are arranged in an upper part of a tap switch box 6. Thereby, the bushing 7 can be attached and detached and the converter 12 can be checked by opening the tap switch box 6 and insulation oil is put in and out inside a tap switch box alone. Therefore, it is possible to eliminate the need for putting in and out oil inside a main body tank 27 for every operation which is required in a conventional method. Furthermore, for opening and closing the tap switch box 6, a door of a hinge structure, for example, can be provided and it is possible to eliminate the need for providing another handle hole for attaching and detaching of the bushing 7 and checking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer with a tap changer, and more particularly to a structure of a bushing lead-out portion of the transformer.

[0002]

2. Description of the Related Art A transformer with a tap changer includes a core body wound with a winding having a tap on an iron core, a tap changer for switching the tap of the tap winding, and a main body tank containing the body. And a bushing current transformer using a bushing for drawing out a lead wire of the transformer winding to the outside and a bushing conductor as a primary.

FIG. 3 is a structural view of this conventional transformer with a tank changer, and is a longitudinal sectional view. In the figure, 1 is a main body of a transformer, 2 is a main body tank for storing the main body 1 together with insulating oil, 3 is a partition plate, and a bushing 4 for tap lead wire penetration is buried therein, and a main body tank 2 is provided. The window hole provided in the side wall of the oiltight is closed.

Reference numeral 5 denotes a tap changer provided outside the partition plate 3 and having an operation mechanism, and operates a movable contact to switch tap leads. Reference numeral 6 denotes a tap changer box that houses the tap changer 5 together with insulating oil, and is configured to be oil-tight. Reference numeral 7 denotes a bushing, which is fixed to the upper plate by penetrating the upper plate (upper lid) of the main body tank 2, and the inner end side is connected to the winding of the main body 1 via connection leads 8.

A conservator 9 is attached to an upper plate of the main tank 2 via an attaching member 10. 11 is a tap lead wire, 12 is a built-in type bushing current transformer, 1
Reference numeral 3 denotes a handhole.

As described above, in the conventional transformer with a tap changer, the bushing 7 and the bushing current transformer 12 are used.
Are mounted in the same main body tank 1 as the contents main body of the transformer.

FIG. 4 shows an example of a transformer winding connection and a tap switching method. FIG. 4 (A) shows a case of a triangular connection, FIG. 4 (B) shows a case of a star line, and the same reference numerals as those in FIG. The same parts are shown.

The taps are switched by operating (rotating) the movable contact 5a of the tap changer 5 and selecting one of the small bushings 4 for tap lead penetration. I have.

[0009]

As described above, in the conventional transformer with a tap changer, since the bushing 7 and the bushing current transformer 12 are mounted in the main body tank 2, the following problems occur. There was a point.

(1) When installing or removing the bushing or checking the bushing current transformer, the oil in the main tank must be drained each time, and the oil must be re-lubricated after the operation is completed. Each of these operations required a complete set of lubricating equipment such as an oil purifier and a vacuum pump and labor for the operations, which was very difficult. Furthermore, when the contents main body is exposed to the air, the contents main body uses a lot of insulating paper, so that it absorbs moisture and deteriorates insulation performance, which is not preferable.

(2) Since the bushings for which the insulation distance must be secured are arranged at the upper part of the main body tank,
The conservator and its accessories cannot be installed on the upper part of the main tank, and extra material is required to extend and attach the mounting member from the upper part of the tank. (3) A handhole 13 and a manhole are required for mounting, removing, and checking the bushing and the bushing current transformer.

The present invention has been made in view of the above points, and solves the conventional problems by mounting and removing a bushing and a bushing current transformer not in a main body tank but in a tap changer box. What you want to do.

[0013]

Means for solving the above-mentioned problems in the present invention are as follows. A transformer body in which a winding having a tap is wound is housed in a main body tank, and a tank is provided on a side wall of the tank. A tap changer box forming a separate chamber from the tap changer box, and a tap changer with a tap changer for changing the tap of the tap winding housed in the tap changer box. A bushing for drawing out the lead wire of the wire to the outside is provided, and a bushing current transformer is provided in the tap changer box.

As described above, since the bushing and the bushing current transformer are provided in the tap changer box in a separate room from the main body tank, the oil in the main body tank is taken in and out each time the bushing is attached and detached and the bushing current transformer is checked. The above-mentioned problem is solved.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of a transformer with a tap changer according to an embodiment of the present invention, and FIG. 2 is a top view of the transformer. In the present invention, a bushing 7 and a bushing current transformer 12 are connected to a tap changer box 6. It is characterized by being arranged at the top.

The same or corresponding parts as those in FIG. 3 are denoted by the same reference numerals and description thereof will be omitted.

By providing the bushing 7 and the bushing current transformer 12 in the tap changer box 6 in a separate room from the main body tank 2 of the transformer, mounting of the bushing is achieved.
When removing and checking the current transformer, the tap changer box 6 may be opened, and the insulating oil can be taken only in and out of the tap changer box. You don't have to.

The opening and closing of the tap changer box 6 is made possible, for example, by providing a hinged door which can be easily opened and closed.
With such a door structure that can be easily opened and closed, it is not necessary to separately provide a handle hole for attaching, detaching, and checking the bushing.

[0020]

As described above, according to the present invention, the bushing and the bushing current transformer are provided in the tap changer box in a separate room from the main body tank, so that the following effects are exhibited.

(1) Installation and removal of the bushing
Each time the bushing current transformer is checked, it is not necessary to take oil in and out of the main body tank of the transformer. As a result, the number of working steps is reduced, and furthermore, an excellent effect is obtained in terms of maintaining the quality of the content main body that uses a lot of insulating paper.

(2) Since the tap changer box can be a hinged door which can be easily opened and closed to check the changer, a handhole for attaching, detaching and checking the bushing is separately provided. There is no need to provide them.

(3) In disassembly and transportation, the bushing and the tap changer box can be integrally transported.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the present invention.

FIG. 2 is a top view of FIG. 1;

FIG. 3 is a longitudinal sectional view of a conventional transformer with a tap changer.

FIG. 4 is a circuit configuration diagram of a transformer with a tap changer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Contents main body 2 ... Main body tank 3 ... Partition plate 4 ... Small bushing for tap lead penetration 5 ... Tap changer 6 ... Tap changer box 7 ... Bushing 8 ... Connection lead 9 ... Conservator 10 ... Mounting member 11 ... Tap lead Line 12: Bushing current transformer 13: Hand hole

Claims (1)

[Claims] 1. A transformer body containing a transformer having a tap wound thereon is housed in a main body tank, and a tank switch box is formed on the side wall of the tank to form a separate chamber from the tank. A tap changer with a tap changer for switching taps of the tap windings therein, wherein the tap changer box is provided with a bushing for drawing out a lead wire of the winding to the outside; A transformer with a tap switch, wherein a bushing current transformer is provided in the tap switch box.