JP7232608B2 - static induction electric machine - Google Patents

Description

The present invention relates to static induction appliances.

In general, stationary induction electric appliances such as transformers and reactors always generate noise during energization. Since the noise of this static induction electric appliance causes deterioration of the living environment of the residents in the vicinity where this static induction electric appliance is installed, a low noise level is required.

Normally, the noise level of a stationary induction machine is set according to its installation location.

Static induction electric machine noise is caused by magnetostrictive vibration generated in the iron core that makes up the main body of the static induction electric machine and electromagnetic vibration generated in the coil, which propagates to the tank that covers the iron core and coil, and is radiated from the surface of the tank to the outside. Occur.

Also, depending on the structure and shape of the tank covering the main body of the stationary induction electric machine, a resonance phenomenon appears, so the frequency of the noise fluctuates.

In order to reduce the noise of such a static induction electric machine, the body of the static induction electric machine is often covered with a soundproof structure such as a soundproof tank, a soundproof building, or a soundproof wall made of steel plate or concrete.

In order to further attenuate the generated noise, there is also known a method of installing a sound absorbing structure inside the soundproof structure.

As a background art of this technical field, there is Japanese Patent Application Laid-Open No. 2013-21035 (Patent Document 1). In this patent document 1, in a noise reduction structure for a transformer having a soundproof wall covering the periphery of the transformer main body, a resonance type sound absorbing structure that resonates with a specific frequency of noise generated in the operating state of the transformer is provided on the outer surface of the transformer. and the inner surface of the soundproof wall.

Japanese Unexamined Patent Application Publication No. 2013-21035

Patent Literature 1 describes installing a resonance type sound absorbing structure on a floor to reduce noise of a transformer. However, Patent Literature 1 does not describe how to reduce the noise of the static induction electric machine radiated from the bottom surface of the tank that surrounds the static induction electric machine main body.

SUMMARY OF THE INVENTION Accordingly, the present invention provides a static induction electric appliance that efficiently reduces the noise of the static induction electric appliance emitted from the bottom surface of the tank that surrounds the static induction electric appliance main body.

In order to solve the above-mentioned problems, the static induction electric appliance of the present invention comprises: a static induction electric appliance main body; a tank covering the periphery of the stationary induction electric appliance main body ; a support structure for supporting the tank; a sound absorbing structure for absorbing, a hole is formed in the ground in which the support structure is installed, the support structure abuts the bottom of the hole and the bottom surface of the tank is installed below the surface of the ground and , there is a space between the bottom of the tank and the bottom of the hole, the sound absorbing structure is located below the bottom of the tank and at the bottom of the hole, between the lower side of the tank and the upper side of the hole placed in between .

According to the present invention, it is possible to provide a stationary induction electric appliance that efficiently reduces the noise of the stationary induction appliance radiated from the bottom surface of the tank that surrounds the stationary induction appliance main body.

Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

1 is a cross-sectional view showing a stationary induction electric appliance of Example 1. FIG. 4 is a graph of the spectrum of noise emitted from the bottom of the tank to the outside. FIG. 4 is an explanatory diagram showing a sound absorbing structure arranged in the static induction electric appliance of Example 1; FIG. 10 is a cross-sectional view showing a stationary induction electric appliance of Example 2; FIG. 11 is an explanatory diagram showing the arrangement of sound absorbing structures installed in the stationary induction appliance of Example 2; FIG. 11 is a cross-sectional view showing a stationary induction electric appliance of Example 3;

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, the same code|symbol is attached|subjected to the same structure, and when description overlaps, the description may be abbreviate|omitted.

FIG. 1 is a cross-sectional view showing a static induction electric appliance of Example 1. FIG.

A static induction electric appliance 10 such as a transformer or reactor comprises a static induction electric appliance main body (transformer, reactor or other main body) 9 having an iron core around which a coil is wound, and a support made of iron or the like that supports the stationary induction electric appliance main body 9. A structure 5, a tank 1 made of iron or the like that covers the periphery of a stationary induction electric appliance body 9, a support structure 4 made of iron or concrete or the like that supports the tank 1, and a plurality of structures that absorb noise radiated from the bottom surface 12 of the tank 1. and a reinforcing member 11 that reinforces the tank 1 .

The support structure 5 is installed inside the tank 1 and contacts the bottom surface 12 of the tank 1 from the inside of the tank 1 . Moreover, the support structure 4 is installed outside the tank 1 and contacts the bottom surface 12 of the tank 1 from the outside of the tank 1 . That is, the support structure 5 and the support structure 4 are in contact with the bottom surface 12 of the tank 1 .

In this embodiment, holes are formed in the ground 3 in which the support structure 4 is installed. The support structure 4 then contacts the bottom 31 of the hole. The bottom surface 12 of the tank 1 is installed at a position lower (lower) than the ground surface 32 of the ground 3 . The tank 1 is supported on a support structure 4 installed in this hole. That is, a predetermined space is formed between the bottom surface 12 of the tank 1 and the bottom 31 of the hole.

Also, the size of this hole is slightly larger than the size (width and depth) of the tank 1 . That is, a predetermined space is formed between the side surface of the tank 1 located below the ground surface 32 of the ground 3 and the side surface of the hole.

And in this embodiment, a plurality of sound absorbing structures 2 are arranged in this space. The sound absorbing structure 2 is arranged below the bottom surface 12 of the tank 1 . In particular, the sound absorbing structure 2 is preferably arranged in the vicinity of the support structure 4 . That is, a sound absorbing structure (sound absorbing structure using the Helmholtz resonance principle) 2 is arranged under the bottom surface 12 of the tank 1 .

The sound absorbing structure 2 is mounted on the bottom 31 of the hole, which is the lower part of the bottom surface 12 of the tank 1, and also on the side of the tank 1 (lower side) and the side of the hole (upper side) located below the ground surface 32 of the ground 3. It is arranged so as to fill the space formed between and further embedded in the side surface of the hole.

Moreover, the sound absorbing structure 2 is arranged so that all the openings 23 formed in the sound absorbing structure 2 face the inside of the space. That is, the sound absorbing structure 2 is arranged in the tank 1 at a position lower than the ground surface 32 of the ground 3 with the opening 23 of the sound absorbing structure 2 arranged at the bottom 31 of the hole which is the lower part of the bottom surface 12 of the tank 1 upward. The opening 23 of the sound absorbing structure 2 arranged to fill the space formed between the side surface and the side surface of the hole is below, and the opening of the sound absorbing structure 2 arranged so as to be embedded in the side surface of the hole. The parts 23 are arranged so as to face the inside of the space.

As a result, the noise of the stationary induction electric machine 10 radiated from the bottom surface 12 of the tank 1 covering the periphery of the stationary induction electric machine main body 9 (noise generated by the stationary induction electric machine 10 and radiated to the outside) can be efficiently reduced. can be done.

The stationary induction appliance main body 9 has an iron core around which a coil is wound.

Magnetostrictive vibration generated in the iron core and electromagnetic vibration generated in the coil propagate from the support structure 5 that supports the stationary induction appliance main body 9 to the bottom surface 12 of the tank 1 on which the support structure 5 is installed. Also, some of these vibrations resonate between the support structure 5 and the bottom surface 12 of the tank 1 . It has been found that such propagation and resonance are radiated from the bottom surface 12 of the tank 1 to the outside, causing the noise of the stationary induction electric machine 10 to occur.

That is, the magnetostrictive vibration generated in the iron core constituting the stationary induction electric appliance main body 9 and the electromagnetic vibration generated in the coil are transmitted from the supporting structure 5 installed in contact with the stationary induction electric appliance main body 9 (especially, the iron core) to the supporting structure 5. It propagates to the bottom surface 12 of the tank 1 installed at the bottom. Also, some of these vibrations resonate between the support structure 5 and the bottom surface 12 of the tank 1 . Therefore, it was found that the noise of the static induction electric machine 10 radiated to the outside is radiated from the bottom surface 12 of the tank 1 (under the static induction electric machine 10).

Therefore, it has been found that the sound absorbing structure 2 must be arranged below the bottom surface 12 of the tank 1 in order to effectively reduce the noise of the static induction electric machine 10 .

Thus, according to the present embodiment, by arranging the sound absorbing structure 2 under the bottom surface 12 of the tank 1, the noise radiated from the bottom surface 12 of the tank 1 can be efficiently reduced.

Further, according to this embodiment, the noise of the static induction electric machine 10 can be reduced without arranging the sound absorbing structure 2 inside the tank 1 constituting the static induction electric machine 10 . As a result, the space formed inside the tank 1 can be reduced, and the installation area of the static induction electric machine 10 can be reduced.

Focusing on the positional relationship between the iron core around which the coil is wound and the tank 1 , it can be seen that the bottom surface 12 of the tank 1 is in contact with the iron core the most. Therefore, the static induction electric machine 10 emits the largest noise from the bottom surface 12 of the tank 1 and can be said to be the main cause of the noise of the static induction electric machine 10 . Therefore, by reducing the noise emitted from the bottom surface 12 of the tank 1, the noise of the stationary induction electric machine 10 can be effectively reduced.

Moreover, in this embodiment, the sound absorbing structure 2 is arranged below the ground surface 32 of the ground 3, that is, in the ground. In particular, the sound absorbing structure 2 is formed at the bottom 31 of the hole, which is the lower part of the bottom surface 12 of the tank 1 (and also between the side of the tank 1 below the surface of the ground 3 and the side of the hole). space-filling and embedded in the sides of the hole).

Therefore, the noise radiated from the bottom surface 12 of the tank 1 is less likely to leak into the air. Moreover, since the attenuation characteristic of the ground 3 can be used, the noise of the stationary induction electric machine 10 can be greatly reduced.

FIG. 2 is a graph of the spectrum of noise emitted from the bottom surface of the tank to the outside, and shows the distribution (one example) of the noise emitted from the bottom surface 12 of the tank 1 to the outside.

As shown in FIG. 2, the noise emitted from the bottom surface 12 of the tank 1 to the outside (noise generated from the stationary induction electric machine 10) is large at specific frequencies (for example, 100 Hz, 300 Hz, 500 Hz, 700 Hz, etc.). I understand. Therefore, if the noise of these specific frequencies is absorbed using the sound absorbing structure 2 arranged under the bottom surface 12 of the tank 1, the noise generated from the stationary induction electric machine 10 can be more effectively reduced. can do.

FIG. 3 is an explanatory diagram showing a sound absorbing structure arranged in the stationary induction appliance of Example 1. FIG.

The sound absorbing structure 2 has a cavity 21 , a nested structure 22 for adjusting the volume of the cavity 21 , and an opening 23 .

Here, c [m/sec] is the speed of the sound transmission medium in the cavity 21, that is, the speed of sound in the air, d [m] is the diameter of the opening 23, l [m] is the length of the opening 23, and l [m] is the length of the opening. Let s [m2] be the area of 23 and V [m3] be the volume of cavity 21 .

At this time, as shown in Equation (1) based on Helmholtz's resonance principle, it resonates at a frequency f [Hz], and the noise of this frequency radiated from the bottom surface 12 of the tank 1 can be absorbed.

Therefore, by adjusting the volume of the hollow portion 21, noise of multiple frequencies can be absorbed. In order to adjust the volume of the cavity 21, the length by which the nested structure 22 enters the cavity 21 is adjusted. The nested structure 22 can be adjusted in length to enter the cavity 21 . That is, in FIG. 3, the telescopic structure 22 moves left and right with respect to the cavity 21 to adjust the length of its entry, thereby adjusting the volume of the cavity 21 . By adjusting the volume of the cavity 21, the frequency of the noise to be absorbed can be adjusted.

In this way, by arranging the sound absorbing structure 2 capable of absorbing noise of various frequencies under the bottom surface 12 of the tank 1, the noise of various frequencies radiated from the bottom surface 12 of the tank 1 can be effectively absorbed. can be substantially reduced.

For example, by adjusting the volume of the cavity 21, it is possible to reduce noise radiated from the bottom surface 12 of the tank 1 to the outside, that is, noise of specific frequencies (100 Hz, 300 Hz, 500 Hz, 700 Hz).

That is, the volume of the cavity 21 of a plurality of sound absorbing structures 2 is set so as to absorb noise with a frequency of 100 Hz. Also, the volume of the cavity 21 of a plurality of sound absorbing structures 2 is adjusted to absorb noise with a frequency of 500 Hz, and the volume of the cavity 21 of a plurality of sound absorbing structures 2 By arranging a plurality of adjusted sound absorbing structures 2, each of which is adjusted so as to absorb noise of a frequency of 700 Hz, the noise of these frequencies radiated from the bottom surface 12 of the tank 1 can be efficiently can be reduced to

Here, calculation examples for a frequency of 100 Hz and a frequency of 200 Hz will be described.

The velocity of the acoustic transmission medium in the cavity 21, that is, the sound velocity of air c [m/sec] is 340 m/s, the area s [m2] of the opening 23 is 3.848×10 ⁻⁶ m ² , and the volume of the cavity 21 is Assuming that V [m3] is 7.4×10 ⁻⁵ m ³ , the length l [m] of the opening 23 is 0.001 m, and the opening 23 is circular, the frequency is 100 Hz according to the formula (1). can be realized. The radius of the opening 23 is 0.0178m.

In addition, the velocity of the acoustic transmission medium in the cavity 21, that is, the sound velocity c [m/sec] of the air, is 340 m/s, the area s [m2] of the opening 23 is 3.848×10 ⁻⁴ m ² , and the cavity 21 Assuming that the volume V [m3] of is 0.00185 m ³ and the length l [m] of the opening 23 is 0.001 m, the sound absorbing structure with a frequency of 200 Hz is obtained by equation (1) when the opening 23 is circular. Body 2 can be realized. The radius of the opening 23 is 0.0178m.

In addition, the frequency of noise generated by the static induction electric machine 10 fluctuates depending on the structure and shape of the static induction electric machine 10 . Therefore, it is necessary to reduce noise of various frequencies generated at the site (installation location) where the stationary induction electric appliance 10 is installed.

In this embodiment, the sound absorbing structure 2 is used which can adjust the volume of the cavity 21 using the nested structure 22 . The nested structure 22 is used to adjust the volume of the cavity 21 so as to resonate with noise of various frequencies generated at the site (installation location) where the stationary induction electric appliance 10 is installed. As a result, noise of various frequencies generated at the site (installation site) can be easily reduced at the site (installation site).

In addition, the sound absorbing structure 2 has a structure (for example, a bolt or the like) for fixing the position (length of insertion) of the nested structure 22 .

Moreover, the sound absorbing structure 2 may have a structure in which the hollow portion 21 is filled with a porous sound absorbing material (for example, sponge or the like).

As described above, according to this embodiment, there is no need to cover the periphery of the static induction electric appliance main body 9 with a soundproof structure such as a soundproof tank, a soundproof building, or a soundproof wall, so that the installation area of the static induction electric appliance 10 can be reduced. be able to. Furthermore, since such a soundproof structure is not required and the installation area of the static induction electric machine 10 can be reduced, the cost can be reduced. Then, the noise of the stationary induction electric machine 10 can be reduced in accordance with the fluctuation of the frequency of the radiated noise and in accordance with the type of frequency of the radiated noise.

In this embodiment, the noise of the stationary induction electric appliance 10 is reduced by the synergistic effect of the sound reduction by the attenuation characteristics of the ground 3 and the sound absorption by the sound absorbing structure 2 . Moreover, by arranging the sound absorbing structure 2 in the lower part of the tank 1, both reduction of the installation space and reduction of noise can be achieved.

According to this embodiment, the cost can be reduced by arranging the sound absorbing structure 2 utilizing the Helmholtz resonance principle under the bottom surface 12 of the tank 1 where the stationary induction electric machine 10 makes a large noise. Furthermore, since the resonance frequency of the sound absorbing structure 2 can be adjusted, noise can be reduced even when the frequency of noise fluctuates or when noise of multiple frequencies appears.

FIG. 4 is a cross-sectional view showing a stationary induction appliance of Example 2. FIG.

Also in this embodiment, the bottom surface 12 of the tank 1 is installed at a position lower than the ground surface 32 of the ground 3 (below). The tank 1 is then supported on a support structure 4 installed in this hole. That is, a predetermined space is formed between the bottom surface 12 of the tank 1 and the bottom 31 of the hole.

Also, in this embodiment, the size of this hole is formed to be substantially the same as the size (width and depth) of the tank 1 . That is, unlike the first embodiment, a predetermined space is not formed between the side surface of the tank 1 located below the ground surface 32 of the ground 3 and the side surface of the hole. Concrete 7 is formed on the side surface of this hole.

Also in this embodiment, a plurality of sound absorbing structures 2 are arranged in this space. The sound absorbing structure 2 is arranged below the bottom surface 12 of the tank 1 . In particular, the sound absorbing structure 2 is arranged on both sides of the support structure 4 .

That is, the sound absorbing structure 2 is arranged at the bottom 31 of the hole, which is the lower part of the bottom surface 12 of the tank 1 .

Moreover, the sound absorbing structure 2 is arranged so that all the openings 23 formed in the sound absorbing structure 2 face the inside of the space. That is, the sound absorbing structure 2 is arranged so that the opening 23 of the sound absorbing structure 2 arranged at the bottom 31 of the hole, which is the lower part of the bottom surface 12 of the tank 1, faces upward.

The noise radiated from the bottom surface 12 of the tank 1 is less likely to leak into the air due to the concrete 7 formed on the side surface of the hole in this way. Therefore, the noise of the stationary induction electric machine 10 can be greatly reduced.

FIG. 5 is an explanatory diagram showing the arrangement of the sound absorbing structure installed in the stationary induction electric appliance of Example 2, and is a bird's-eye view of the arrangement of the sound absorbing structure 2 shown in FIG.

The sound absorbing structure 2 is arranged on both sides of the support structure 4 between the front and the back. Concrete 7 is formed all around the sides of the hole. The side surface of the stationary induction electric machine 10 and the concrete 7 are in contact with each other.

This makes it possible to reduce the frequency of noise emitted from the bottom surface 12 of the tank 1 and the frequency of noise generated by resonance between the support structure 5 and the bottom surface 12 of the tank 1 .

Furthermore, noise emitted from the bottom surface 12 of the tank 1 is shielded by the concrete 7 formed in the hole, so noise leaking into the air can be reduced.

Moreover, in this embodiment, the number of sound absorbing structures 2 to be arranged can be reduced, and cost reduction is possible.

In this embodiment, the sound absorbing structure 2 is arranged below the ground surface 32 of the ground 3, that is, in the ground. In particular, the sound absorbing structure 2 is arranged at the bottom 31 of the hole, which is the lower part of the bottom 12 of the tank 1 . Therefore, the noise radiated from the bottom surface 12 of the tank 1 is less likely to leak into the air, and the attenuation characteristics of the ground 3 can be used, so that the noise of the stationary induction electric machine 10 can be greatly reduced.

In this embodiment, the noise of the stationary induction electric appliance 10 is reduced by the synergistic effect of the sound reduction by the attenuation characteristics of the concrete 7 and the sound absorption by the sound absorbing structure 2 . Moreover, by arranging the sound absorbing structure 2 in the lower part of the tank 1, both reduction of the installation space and reduction of noise can be achieved.

According to this embodiment, the cost can be reduced by arranging the sound absorbing structure 2 utilizing the Helmholtz resonance principle under the bottom surface 12 of the tank 1 where the stationary induction electric machine 10 makes a large noise. Furthermore, since the resonance frequency of the sound absorbing structure 2 can be adjusted, noise can be reduced even when the frequency of noise fluctuates or when noise of multiple frequencies appears.

FIG. 6 is a cross-sectional view showing a stationary induction appliance of Example 3. FIG.

In this embodiment the tank 1 is supported on a support structure 4 which is placed on the ground surface 32 of the ground 3 . That is, the bottom surface 12 of the tank 1 is installed at a position higher than the ground surface 32 of the ground 3 . A predetermined space is formed between the bottom surface 12 of the tank 1 and the ground surface 32 of the ground 3 .

In this embodiment, a plurality of sound absorbing structures 2 are arranged in this space. The sound absorbing structure 2 is arranged under the bottom surface 12 of the tank 1 and on the ground surface 32 of the ground 3 . In particular, the sound absorbing structure 2 is preferably arranged in the vicinity of the support structure 4 .

Further, the sound absorbing structure 2 arranged below the bottom surface 12 of the tank 1 is arranged so that all the openings 23 formed in the sound absorbing structure 2 face upward.

In this embodiment, the sound absorbing structure 2 is arranged to be larger than the size (width and depth) of the tank 1 in particular.

A sound insulating material 8 made of iron or the like is installed on the lower side surface of the tank 1 so as to cover the lower side surface of the tank 1 . The sound absorbing structure 2 is also arranged inside the sound insulating material 8 so that the opening 23 faces inward. One of the ends of the sound insulating material 8 is placed on the ground surface 32 of the ground 3 and the other end of the sound insulating material 8 is placed on the side surface of the tank 1 of the stationary induction electric appliance 10 .

Thereby, the sound absorbing structure 2 absorbs noise emitted from the bottom surface 12 of the tank 1 . The noise reflected by the ground surface 32 of the ground 3 and part of the noise emitted from the lower side surface of the tank 1 are absorbed by the sound absorbing structure 2 arranged inside the sound insulating material 8 .

In addition, the height of the support structure 4 is adjusted in order to suppress an increase in the noise level caused by reflection of noise (sound waves) (noise radiated from the bottom surface 12 of the tank 1 reflected on the ground surface 32 of the ground 3). preferably.

Since the sound insulation material 8 is used to reduce the noise radiated to the outside, the noise of the stationary induction electric machine 10 can be effectively reduced. In addition, since this embodiment does not require a hole to be formed in the ground 3, it can be applied to the existing stationary induction electric machine 10 as well.

In addition, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the described configurations. It is also possible to replace part of the configuration of one embodiment with the configuration of another embodiment.

Reference Signs List 1... Tank 2... Sound absorbing structure 3... Ground 4... Support structure for tank 5... Support structure for main body of static induction electric machine 7... Concrete 8... Sound insulating material 9... Main body for static induction electric machine 10... Static induction electric machine 11... Reinforcing member for tank REFERENCE SIGNS LIST 12: Bottom of tank 21: Cavity 22: Nested structure 23: Opening 31: Bottom of hole 32: Ground surface

Claims (3)

A static induction electric appliance body, a tank surrounding the static induction electric appliance body, a support structure for supporting the tank , and a sound absorbing structure for absorbing noise radiated from the bottom surface of the tank ,
A hole is formed in the ground in which the support structure is installed, the support structure is in contact with the bottom of the hole, the bottom surface of the tank is installed below the surface of the ground, and the bottom surface of the tank and the hole are in contact with each other. has a space between the bottom of
The static induction electric machine, wherein the sound absorbing structure is arranged at the bottom of the bottom of the tank, at the bottom of the hole, and between the lower side of the tank and the upper side of the hole. . 2. The static induction electric machine according to claim 1, wherein said sound absorbing structure has a nested structure capable of adjusting the volume of said cavity. 3. The stationary induction electric appliance according to claim 2, wherein the sound absorbing structure has a porous sound absorbing material inside the cavity.

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