JPS6144413Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an induction electric device having an improved cooling structure for a magnetic shield installed to reduce stray loss.

Conventional induction electric appliances such as transformers and reactors are constructed by storing the contents of the induction electric appliance, which consists of an iron core and a coil wound around the iron core, inside a tank together with an insulating medium. As shown in FIG. 1, a magnetic shield is attached to the inner wall of the tank on the opposite surface of the coil for returning leakage magnetic flux from the coil.

The magnetic shield 6 is generally formed by arranging a plurality of blocks 6a, each consisting of a required number of laminated silicon steel plates with high magnetic permeability and a width of 100 to 200 mm, at intervals 7 perpendicular to the inner wall of the tank. In addition, since each block 6a of the magnetic shield 6 is formed from a thin silicon steel plate, the periphery thereof has an acute angle shape, and when facing a live part such as a high voltage coil or a coil outlet, the electric field It is easy to concentrate.
Therefore, a frame member 8 made of a metal member with rounded corners is provided around the mounting portion of the magnetic shield 6 to alleviate the electric field. Furthermore, the coil 2 and the magnetic shield 6
In order to shorten the insulation dimension between the magnetic shield 6 and the magnetic shield 6, an insulation barrier 9 made of a plate-shaped insulation member is attached so as to be in close contact with the surface of the magnetic shield 6. Although not shown, especially when the outer coil of the coil 2 is wound vertically and the high voltage line end is at the center of the height of the coil, an insulating barrier 9 containing a ground electrode, which is a plate-shaped insulating member lined with a ground electrode, is used. Install. In either case, the insulating barrier 9 connects the insulating stud 1 to the insulating stud 1 by using a tap hole cut in the frame member 8 for mitigating the electric field.
It is fixed as 0 etc.

In the conventional configuration as described above, the heat generated due to the loss generated when the leakage magnetic flux passes through the silicon steel plate is absorbed by the surrounding insulating oil 4 by the insulating barrier 9 and the frame member 8 for mitigating the surrounding electric field. Due to the sealed state, heat dissipation becomes poor, which may lead to thermal deterioration or damage to the insulating members including the insulating barrier 9.

This invention was made taking the above points into consideration.
The purpose is to provide a highly reliable induction electric appliance with improved cooling effect of the magnetic shield.

Hereinafter, the present invention will be described with reference to an embodiment shown in the drawings in which the same parts as in FIG. 1 are denoted by the same reference numerals. Second
In the figure, an induction electric appliance such as a transformer or a reactor is made up of an iron core 1 and a coil 2 wound around the iron core ₁ . It is constructed by being housed inside a tank 5 together with an insulating medium 4 such as a condensable cooling medium. As shown in FIG. 3, a magnetic shield 6 is disposed on the inner wall of the tank 5 on a surface facing the coil 2 for returning leakage magnetic flux from the coil 2.

This magnetic shield 6 consists of a plurality of blocks 6a formed by laminating a predetermined number of high-permeability silicon steel plates with a width of 100 to 200 mm, for example, arranged at intervals 7 perpendicular to the inner wall of the tank 5. It is formed by

A frame member 11 made of a metal member with rounded corners for electric field relaxation is provided like a picture frame at a predetermined interval 7a around the area where the magnetic shield 6 is attached. Furthermore, magnetic shield 6
An insulating barrier 9 made of a plate-shaped insulating member or a plate-shaped insulating member having a ground electrode is attached to the frame member 1 using insulating studs 10 so as to be in close contact with the surface of the frame member 1.
Install it on 1.

Further, a plurality of flow portions 12 are formed in the upper and lower portions of the frame member 11, respectively, as shown in FIGS. 3 to 7. The flow portion 12 is formed from a through hole or groove that passes through the frame member 11 along the inner wall of the tank 5 .

Next, the effects of the present invention will be explained. The heat generated in the magnetic shield 6 passes through the gaps 7 between the blocks 6a of the magnetic shield 6 and the gaps 7a between the blocks 6a and the frame member 11, and passes through the circulation portions 12 formed at the upper and lower parts of the frame member 11. It is transmitted by an insulating medium flow caused by natural convection of the insulating medium 4 such that In this way, the cooling effect is improved compared to the conventional case without the flow section 12,
Overheating around the magnetic shield 6 can be prevented.

Further, the frame member 11 is at the same potential as the tank 5, that is, the ground potential, and the rounded corners of the frame member 11 facing the coil 2 suppress electric field concentration. The flow section 12 does not particularly disturb the electric field and does not impair its effectiveness.

Furthermore, if an insulating medium flow is forced to flow through the insulating medium flow path using, for example, a circulation pump, the cooling effect can be further increased.

As explained above, according to the present invention, a frame member is provided around a magnetic shield in which a plurality of blocks are arranged vertically with gaps on the inner wall of the tank facing the coil, and the frame member is placed in close contact with the magnetic shield. By disposing a plate-shaped insulating barrier on the block and forming a plurality of flow parts at the upper and lower parts of the frame member, the insulating medium can flow through the gaps between the blocks and the flow parts. Therefore, the cooling effect around the magnetic shield can be increased, overheating or damage can be prevented, and reliability can be improved.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway plan view showing a conventional magnetic shield, Figs. 2 to 7 show an induction electric device of the present invention, Fig. 2 is a cross-sectional view, and Fig. 3 is a - of Fig. 2.
4 is a right side view of FIG. 3; FIG. 5 is a cross-sectional view of FIG.
FIG. 6 is a side view taken along the - line in FIG. 3, and FIG. 7 is a perspective view showing the main parts. 1...Iron core, 2...Coil, 3...Induction electric device contents, 4...Cooling medium, 5...Tank, 6...Magnetic shield, 6a...Block, 7, 7a...Gap, 9...Insulation Barrier, 11...Frame member, 12
...Distribution department.

Claims (1)

[Scope of utility model registration request] A magnetic shield formed by arranging a plurality of blocks in parallel at selected intervals perpendicular to the inner wall of a tank that houses the contents of an induction device together with an insulating medium, and a frame member provided around this magnetic shield. and an insulating barrier made of an insulating member or an insulating member having a ground electrode attached so as to be in close contact with the surface of the magnetic shield, and a flow path for the insulating medium and a flow path for the insulating medium are provided at the upper and lower portions of the frame member, respectively. An induction electric appliance characterized by forming a plurality of flow parts.