JPH09293622A - Magnetic shield of electric stationery equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide magnetic shielding for electric stationery equipment such as a transformer, a reactor, etc., with the least local overheating. SOLUTION: In the magnetic shields 1a, 1b for such as a transformer, a reactor, etc., the magnetic shield parts wherein the magnetic flux having the vector component vertical to an electric stationery equipment tank 6 is incident are vertically stacked with the thickness direction of a silicon steel sheet comprising the magnetic shield parts 1a, 1b opposed to a coil 5 while the other magnetic shield parts are horizontally stacked with the width direction of the silicon steel sheet opposed to the coil 5 so as to cover up the eddy current loss caused in the magnetic shield on the tank 6 side board. Accordingly, the local overheating in the magnetic shield parts 1a, 1b can be avoided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic shield of an electric stationary device, and more particularly to a magnetic shield of an electric stationary device for preventing local overheating and noise reduction of the magnetic shield of the electric stationary device.

[0002]

2. Description of the Related Art Conventional tank magnetic shields for electric static equipment such as transformers and reactors have the same structure regardless of the vector component of the magnetic flux entering each part of the tank magnetic shield.

For this reason, when the silicon steel plates are stacked flat as shown in FIG. 6, for example, magnetic flux having a vector component perpendicular to the tank side plate is incident near the upper and lower ends of the tank magnetic shield 1a, so that eddy current loss occurs. And the tank magnetic shield 1a caused local overheating.

On the other hand, when silicon steel plates are vertically stacked,
For example, if this is applied to a tank having a curved surface such as a transformer for transporting a vehicle, as shown in FIG. 7, the divided magnetic shields 1b are combined in accordance with the surface of the tank 6, so It takes a lot of man-hours and time to manufacture, and the magnetic loss generated at the connection portion is large, which is a quality problem.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the object of claims 1, 2 and 5 is to provide an electric stationary system for transformers, reactors, etc. with less local overheating. To provide a magnetic shield for equipment. It is another object of claims 3 and 4 to provide a magnetic shield for an electric stationary device such as a transformer or a reactor, which reduces noise during load.

[0006]

In order to achieve the above object, the first aspect of the present invention is to provide a magnetic shield for an electric stationary device such as a transformer or a reactor in which a vector component perpendicular to the tank side plate of the electric stationary device is used. In the magnetic shield part where the magnetic flux has, the silicon steel plates forming the magnetic shield are vertically stacked with the thickness direction facing the coil, and in the other magnetic shield parts, the width direction of the silicon steel plate forming the magnetic shield is set. It is characterized in that it is a flat stack facing the coil.

According to a second aspect of the present invention, in the magnetic shield for an electric stationary device according to the first aspect, the thickness of each magnetic shield having different laminating directions in the laminating direction is thicker than one silicon steel plate width. And According to a third aspect of the present invention, in a magnetic shield of an electric stationary device such as a transformer or a reactor, a sound absorbing material is attached to the magnetic shield.

According to a fourth aspect of the present invention, in the magnetic shield for an electric stationary device according to the third aspect, the thickness direction of the magnetic shield is stepwise stacked, and the magnetic flux density of the magnetic shield increases when loaded on the coil side. It is characterized in that only the silicon steel plate of the nearby magnetic shield part is attached with a sound absorbing material having a higher sound absorbing performance than the other magnetic shield parts.

According to a fifth aspect of the present invention, in the magnetic shield for an electric stationary apparatus according to the first or second aspect, the flat magnetic shield portion facing the coil having the highest magnetic flux density has low loss and high magnetic flux density of silicon. It is characterized by using a steel plate.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1A and 1B show a first embodiment (corresponding to claim 1) of the present invention. FIG. 1A is a side view and FIG. 1B is a perspective view of the tank magnetic shield portion of FIG. 1A. .

As shown in the figure, the tank 6 is vertically stacked on the side plate of the tank 6 where the magnetic flux having a vector component perpendicular to the tank side plate is incident on the side plate of the silicon steel plate in the thickness direction of the coil 5. The shield 1b is attached, and the flat tank magnetic shield 1a in which the width direction of the silicon steel plate faces the coil 5 is attached to the other portion.

In the present embodiment, the eddy current loss generated in the magnetic shield can be reduced by the flow 7 of the magnetic flux generated from the coil, so that the local overheating of the magnetic shield can be prevented.

FIG. 2 shows a second embodiment of the present invention (corresponding to claim 2). FIG. 2A is a side view and FIG. 2B is a direction arrow of the magnetic shield portion of FIG. It is a perspective view. As shown in the figure, a magnetic shield 1b made of a silicon steel plate is attached to the side plate of the tank 6 at a portion where a magnetic flux having a vector component perpendicular to the side plate of the tank is incident. A thickness l ₄ in the laminating direction is thicker than a thickness l ₃ of the magnetic shield 1b, and a magnetic shield 1a having a width l ₂ narrower than a width l ₁ of the magnetic shield 1b in the laminating direction is attached. .

Since the magnetic shield of the present embodiment is constructed as described above, in the gap portion 3 provided between the magnetic shields 1a and 1b having different thicknesses in the stacking direction, the leaked magnetic flux leaks the respective magnetic shields 1a and 1b. It can be prevented from flowing into the surface of the silicon steel plate forming 1b. Therefore, the eddy current loss generated near the gap 3 of the magnetic shields 1a and 1b can be reduced, so that the local overheating of the magnetic shields 1a and 1b near the gap 3 between the magnetic shields 1a and 1b having different stacking directions can be prevented. be able to.

FIG. 3 is a side view of a third embodiment (corresponding to claim 3) of the present invention. As shown in the figure, a magnetic shield 1a surrounded by a sound absorbing material 4a is attached to a side plate of the tank 6, and a magnetic shield 2a surrounded by a sound absorbing material 4a is attached to a clamp to which the coil 5 is attached.

Since the magnetic shields 1a and 2a of this embodiment are constructed as described above, noise generated from the magnetic shield 1a of the side plate of the tank 6 and the magnetic shield 2a of the clamp when loaded is absorbed by the sound absorbing material 4a. Therefore, it is possible to reduce noise generated by the influence of magnetostriction of the silicon steel plate forming the magnetic shield when loaded.

FIG. 4 is a side view of a fourth embodiment (corresponding to claim 4) of the present invention. As shown in the figure, the side plate and the clamp of the tank 6 are attached with a magnetic shield having a two-tiered structure. That is, on the side plate of the tank 6, there is attached a magnetic shield 1d in which the magnetic shield 1a and the magnetic shield 1c surrounded by the sound absorbing material 4b are integrally surrounded by the sound absorbing material 4a. Further, the clamp is provided with a magnetic shield 2d in which the magnetic shield 2a and the magnetic shield 2b surrounded by the sound absorbing material 4b are integrated and the surroundings are surrounded by the sound absorbing material 4a. The sound absorbing performance of the sound absorbing material 4b is higher than that of the sound absorbing material 4a.

Since the magnetic shields 1d and 2d of this embodiment are configured as described above, the noise absorbing material absorbs higher noise generated from the magnetic shield of the clamp and the side plate of the tank near the coil side where the magnetic flux density becomes high when loaded. Can be absorbed, so that noise generated due to the influence of magnetostriction of the silicon steel sheet can be reduced.

FIG. 5 is a side view of a fifth embodiment (corresponding to claim 5) of the present invention. As shown in the figure, the side wall of the tank 6 facing the coil with the highest magnetic flux density is a magnetic shield 1e using a flat stacked low loss silicon steel sheet with high magnetic flux density.
Attach. The magnetic shield 1f using a general-purpose silicon steel plate is attached to the other portions.

Since the magnetic shields 1e and 1f of this embodiment are constructed as described above, the concentration of magnetic flux in the magnetic shield of the tank can be prevented, so that the magnetic shield can be made smaller and lighter and the generated loss can be reduced. You can

[0021]

As described above, according to the first aspect of the present invention.
According to the second aspect, the eddy current loss generated in the magnetic shield of the tank side plate can be reduced, so that local overheating of the magnetic shield can be prevented.

According to the third and fourth aspects of the present invention, since the magnetic shields of the transformer, the tank of the reactor and the clamp are surrounded by the sound absorbing material, magnetic flux flows into these magnetic shields when loaded. It is possible to reduce the noise generated due to the magnetostriction of the silicon steel sheet.

Further, according to the fifth aspect of the present invention, since the magnetic shield using the silicon steel plate of low loss and high magnetic flux density is provided on the side plate of the coil facing portion tank, the entire magnetic shield can be made compact and lightweight. Loss due to magnetic flux concentration can also be reduced.

[Brief description of drawings]

FIG. 1 is a first embodiment of the present invention, in which FIG. 1 (a) is a side view and FIG. 1 (b) is a perspective view of FIG. 1 (a).

FIG. 2 is a second embodiment of the present invention, in which FIG. 2 (a) is a side view and FIG. 2 (b) is a view seen from the direction of arrow A in FIG. 2 (a).

FIG. 3 is a side view of the third embodiment of the present invention.

FIG. 4 is a side view of the fourth embodiment of the present invention.

FIG. 5 is a side view of the fifth embodiment of the present invention.

FIG. 6 is a side view of a magnetic shield attached to a conventional tank and clamp.

FIG. 7 is a side view of a magnetic shield attached to another conventional tank.

[Explanation of symbols]

1a, 1b, 1c, 1d, 1e, 1f, 2a, 2b ... Magnetic shield, 3 ... Gap, 4a, 4b ... Sound absorbing material, 5 ...
Coil, 6 ... Tank, 7 ... Flow of magnetic flux.

Claims (5)

[Claims] 1. In a magnetic shield of an electric stationary device such as a transformer or a reactor, in the magnetic shield part where a magnetic flux having a vector component perpendicular to the side plate of the electric stationary device tank enters, a silicon steel plate forming the magnetic shield is used. Magnetic stacks of electrical static equipment characterized by vertical stacking with the thickness direction facing the coil and other magnetic shield parts being flat stacking with the width direction of the silicon steel plates forming the magnetic shield facing the coil. shield. 2. The magnetic shield for an electric stationary device according to claim 1, wherein the magnetic shields having different laminating directions have a thickness in a laminating direction larger than one silicon steel plate width. Magnetic shield. 3. A magnetic shield for an electric stationary device such as a transformer or a reactor, wherein a sound absorbing material is attached to the magnetic shield. 4. The magnetic shield for an electric stationary apparatus according to claim 3, wherein the thickness direction of the magnetic shield is layered, and the magnetic shield portion near the coil side where the magnetic flux density of the magnetic shield increases when loaded. A magnetic shield for an electric stationary device, characterized in that only a silicon steel plate is attached with a sound absorbing material having a higher sound absorbing performance than other magnetic shield portions. 5. The magnetic shield for an electric stationary apparatus according to claim 1, wherein a low loss, high magnetic flux density silicon steel plate is used in a flat magnetic shield portion facing the coil having the highest magnetic flux density. Characteristic magnetic shield for static equipment.