JP2003243232A - Transformer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To more reduce noises produced by a transformer which is equipped with a tank body surrounded by a noise insulating wall having an opening in its upper part. <P>SOLUTION: This transformer is equipped with a sound generating device which detects noises generated by the tank body and generates sounds that cancel out the noises, whereby the noises can be reduced by an active noise reduction effect and a diffraction effect by the noise insulating wall. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer, and more particularly to a transformer having a noise reduction structure.

[0002]

2. Description of the Related Art In recent years, noise regulations have become strict from the viewpoint of environmental protection, and there is a strong demand for noise reduction of transformers. Noise generated from the transformer body is mainly due to magnetostriction,
The vibration of the iron core caused by the magnetic attraction force, the vibration of the winding caused by the electromagnetic force, etc. are transmitted to the tank and the accessories, and they are vibrated continuously.

Conventionally, as a noise reduction measure for a transformer, noise is surrounded by surrounding the main tank of the transformer with a soundproof building or soundproof tank made of steel plate or concrete panel, or a soundproof structure such as a soundproof wall. It is generally shielded and reduced.

It is desirable that these soundproof structures completely seal the entire transformer, which is originally a noise source. However, for structural reasons such as oil pipes and bushing pockets derived from the main tank of the transformer, it is necessary to provide an opening through which the oil pipes and bushing pockets penetrate, for the structural reasons, and sound is output from this opening. Leakage and reduce noise reduction effect. Also, considering additional measures such as adding a soundproof structure to the transformers of existing substations, it may be physically difficult to install a large-scale soundproof structure such as a soundproof building or a soundproof tank afterwards. There is a problem that only a soundproof structure can be installed, and sufficient noise reduction measures cannot be expected.

As an example of such a soundproof structure, a conventional example of a soundproof structure using a soundproof wall (panel) is shown in FIG. In the figure, 1 is a transformer main body tank that houses a transformer main body including an iron core, windings, etc. 2, a soundproof wall provided so as to surround the side surface of the main body tank 1, and 3 is formed on the soundproof wall. This is the opening. Further, 4 is a sound absorbing material made of felt material or the like provided on the inner surface of the soundproof wall 2 as necessary, and 5 is a bushing of a transformer pulled out from the opening 3.

In the transformer having such a structure, the noise emitted from the body tank 1 is transmitted through the soundproof wall 2 or is emitted to the outside through the opening 3 in the upper part of the soundproof wall 2. It Of these, the noise emitted through the soundproof wall 2 to the outside is considerably reduced in volume due to the transmission loss when passing through the soundproof wall 2. On the other hand, the noise emitted from the opening 3 is reduced more than the noise emitted from the main body tank 1 due to the attenuation due to the diffraction effect of the upper portion of the soundproof wall 2. Further, by the sound absorbing material 4 provided on the inner surface of the soundproof wall 2, particularly by reducing the high frequency components in the noise, a larger noise reducing effect can be expected.

[0007]

However, in the conventional soundproof structure constructed as shown in FIG. 7, since the opening 3 is formed in the upper part of the soundproof wall 2, the noise emitted from the opening 3 is reduced. In many cases, the noise reduction effect of the upper part of the soundproof wall 2 and the noise reduction effect of the sound absorbing material 4 cannot often provide a sufficient noise reduction effect as expected.
Further, in order to enhance the noise reduction effect, it is necessary to make the height of the soundproof wall 2 as high as possible, but when the height of the soundproof wall 2 cannot be made too high due to the structure of the oil pipes and bushing pockets. There is also. For this reason, there is a problem that a sufficient noise reduction effect cannot be obtained. It is an object of the present invention to eliminate the above drawbacks and to obtain a transformer with further reduced noise.

[0008]

In order to achieve the above object, the invention of a transformer according to claim 1 is a transformer main body comprising an iron core, a coil, etc., a main body tank accommodating the transformer main body, A soundproof wall that surrounds the side of the body tank and has an opening at the top, an acoustic sensor that detects the noise of the transformer body, and a position that generates a noise that cancels the noise. And a control device that controls the sound generation device to generate a sound that cancels the noise according to the noise level detected by the sound sensor.

According to the present invention, the noise generated by the transformer is detected by the acoustic sensor, and a sound that cancels the noise is generated by the acoustic generator, and the noise is reduced by the active silencing effect and the diffraction effect of the soundproof wall. To do.

According to a second aspect of the invention, there is provided the transformer according to the first aspect, wherein a sound absorbing material for reflection prevention is attached to at least one of the main body tank and the soundproof wall. According to the present invention, the sound absorbing effect of the sound absorbing material prevents the noise that is about to be emitted from the opening from being reflected by the main body tank or the like.

According to a third aspect of the present invention, in the first or second aspect of the invention, the shape of the upper end of the soundproof wall provided around the side surface of the main body tank of the transformer is approximately V-shaped. Is characterized by. According to this invention, the noise emitted from the opening is reduced by the diffraction effect twice.

According to a fourth aspect of the present invention, in the invention according to the first or second aspect, the shape of the upper end of the soundproof wall provided around the side surface of the main body tank of the transformer is a substantially arc shape. Characterize. According to the present invention, the noise emitted from the opening is reduced by a plurality of diffraction effects.

The invention according to a fifth aspect is the first to the fourth aspects.
The invention described in any one of the above 1 to 5 is characterized in that a partition for partitioning a space between the soundproof wall and the main body tank along the circumferential direction of the main body tank is provided on the inner surface of the soundproof wall. According to the present invention, the noise in the area partitioned by the partition is treated as a plane wave, and the noise is reduced with a small number of acoustic sensors and acoustic generators.

The invention according to a sixth aspect is the first to the fourth aspects.
In the invention described in any one of the above, on the inner surface of the soundproof wall, a partition for partitioning the space between the soundproof wall and the main body tank along the circumferential direction of the main body tank is provided, and the spacing between the partitions is 1 / wavelength of the noise. It is characterized in that it is about 2 or less. According to the present invention, the noise in the area partitioned by the partition is treated as a plane wave, and the noise is reduced with a small number of acoustic sensors and acoustic generators.

[0015]

DETAILED DESCRIPTION OF THE INVENTION A first embodiment of the present invention will be described below with reference to FIG. In FIG.
The same parts as those of the conventional transformer shown in are designated by the same reference numerals.
In FIG. 1, 1 is a transformer main body tank that houses a transformer main body including an iron core and windings, 2 is a soundproof wall surrounding the side surface of the main body tank 1, and 3 is an upper part of the soundproof wall The openings 5 formed are the bushings of the transformer drawn out from the opening 3.

Reference numerals 6a and 6b denote sound generators such as speakers installed in the vicinity of the opening 3 above the soundproof wall 2, and sound for canceling noise emitted from the main body tank 1 in the soundproof wall 2. Are placed in such a position as to generate. Reference numeral 7 is an acceleration sensor attached to the main body tank 1 of the transformer, and 8a, 8b and 8c are plural microphones for detecting noise from the main body tank 2 around the main body tank 1 or in the vicinity of the opening 3. It is located in a different position. Acoustic sensors such as the speakers 6a and 6b, the acceleration sensor 7, and the microphones 8a, 8b, and 8c are connected to the control device 10 via control cables 9a to 9f.

With the transformer constructed in this manner, the noise emitted from the main body tank 1 of the transformer is transmitted to the outside after being attenuated through the soundproof wall 2 provided around the side surface of the main body tank 1. There are two types: those that are directly discharged from the opening 3 and those that are transmitted to the outside. Regarding the noise that is transmitted through the soundproof wall 2 and is emitted to the outside, the sound volume is considerably reduced due to the transmission loss when passing through the soundproof wall 2. On the other hand, regarding noise emitted directly from the opening 3 to the outside, the acceleration sensor 7 attached to the main body tank 1 or the microphones 8 a, 8 b, 8 provided around the main body tank 1.
A signal corresponding to the noise level is measured by an acoustic sensor such as c, the measured signal is input to the control device 10, and the control device 10 is optimal for canceling the noise according to the noise level. The signal is calculated and the speaker 6
A and 6b are drive-controlled to generate a noise canceling noise from the speakers 6a and 6b toward the noise, and the noise is reduced by the active noise reduction effect. Due to this active sound deadening effect, the transformer noise can be effectively and sufficiently reduced as compared with the conventional soundproof wall having a soundproof structure.

FIG. 2 shows a modification of the first embodiment of the present invention shown in FIG. 1, in which a sound absorbing material 11 is attached to the sound source side near the opening 3, that is, on the outer surface of the main body tank 1 to prevent reflection. It is configured to take measures.

With such a structure, it is possible to prevent the noise that is about to be emitted from the opening 3 from being reflected on the main body tank 1 or the like and lowering the active silencing effect, and to reduce the noise more effectively. Can be achieved. The sound absorbing material 11 may be attached to the soundproof wall 2 side, or even if it is attached to both the main body tank 1 and the soundproof wall 2, the antireflection effect can be obtained.

Next, a second embodiment of the present invention will be described with reference to FIG. In FIG. 3, the first shown in FIG.
The same parts as those of the embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In the present embodiment, the upper end of the soundproof wall 2 provided around the side surface of the main body tank 1 is divided into two forks to form a substantially V-shaped portion 12.

With such a configuration, the V-shaped portion 1 of the soundproof wall 2 against noise emitted from the opening 3 is formed.
At 2, the diffraction effect is obtained twice. For this reason, the effect of transmission loss due to the V-shaped outer portion of the first-time diffracted wave is also added, and the noise attenuation effect due to diffraction is greater than in the case of a general flat soundproof wall configuration. As a result, in addition to the noise reduction effect by the active noise reduction effect, the noise reduction effect by the more effective diffraction effect is added, and a larger noise reduction effect can be expected. This configuration is particularly effective in the low frequency region.

FIG. 4 shows a modification of the second embodiment of the present invention shown in FIG. 3, in which the upper end of the soundproof wall 2 provided around the side surface of the main body tank 1 is rounded to form a substantially arc-shaped portion. Thirteen
Is formed.

With such a configuration, the diffraction phenomenon occurs a plurality of times in the arc-shaped portion 13 with respect to the noise emitted from the opening 3. This allows
In addition to the noise reduction effect by the active noise reduction effect, the noise reduction effect by the more effective diffraction effect is added, and a larger noise reduction effect can be expected. Also in this configuration, it is particularly effective in the low frequency region.

Although the arc-shaped portion 13 is a perfect circle in FIG. 4, there is no problem as long as there is an arc portion sufficient to obtain a sufficient diffraction effect, and it is not necessary to limit the shape to that shown in FIG. .

Next, a third embodiment of the present invention will be described with reference to FIG. 5, the same parts as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted. In the present embodiment, the main body tank 1
On the inner surface of the soundproof wall 2 provided around the side surface of the soundproof wall 2, there is a plate-shaped partition 15 that partitions a space 14 between the soundproof wall 2 and the main body tank 1 along the circumferential direction of the main body tank 1. Is provided over almost the entire height direction. Partition 15
A speaker 6 and a microphone 8 are attached to each of the areas 16 partitioned by.

With this structure, the sound field inside the soundproof wall 2 is partitioned by the partition 15 provided on the inner surface of the soundproof wall 2 with respect to the noise emitted from the opening 3. In this region, the sound pressure distribution has no nodes and can be treated as a plane wave. Since it can be handled as a plane wave, in the case of a complicated sound field, the number of speakers, microphones, etc. required in large numbers can be set to about one set in one area. Therefore, compared with the case where the partition 15 is not added, it is possible to reduce the noise due to the active noise reduction effect with a simpler configuration, and it is possible to realize the noise reduction more effectively. In this case, as shown in FIG. 6, by dividing the intervals L1 and L2 of the partitions 15 attached to the inner surface of the soundproof wall 2 to about 1/2 or less of the wavelength of the target noise, the partitions partitioned by the partitions 15 are separated. Inside, noise can be treated as a perfect plane wave, so a large noise reduction effect can be expected with a simpler configuration.

In the above description of the embodiment, the case where a plurality of microphones 8a, 8b, 8c are provided as means for detecting the noise from the main body tank 1 has been described, but this number is particularly limited to that shown in FIG. Alternatively, the noise may be detected by either the acceleration sensor or the microphone. Further, the position where the speaker, the microphone and the like are attached may be changed as appropriate as long as the position where the active noise reduction effect can be maximized.

[0028]

As described above, according to the present invention,
A transformer main body composed of an iron core, a coil, etc., a main body tank accommodating this transformer main body, a soundproof wall provided so as to surround the side surface periphery of the main body tank, and having an opening formed in the upper part,
An acoustic sensor that detects the noise of the transformer body, an acoustic generator that is placed at a position that generates a noise that cancels the noise, and an acoustic sensor that responds to the noise bell detected by the acoustic sensor. Since the control device controls the generator so as to generate a noise that cancels the noise, it is possible to obtain a transformer with further reduced noise.

[Brief description of drawings]

FIG. 1 is a front view showing a transformer according to a first embodiment of the present invention.

FIG. 2 is a front view showing a modified example of the transformer according to the first embodiment of the present invention.

FIG. 3 is a front view showing a transformer according to a second embodiment of the present invention.

FIG. 4 is a front view showing a modified example of the transformer according to the second embodiment of the present invention.

FIG. 5 is a plan view showing a transformer according to a third embodiment of the present invention.

FIG. 6 is a plan view showing a transformer according to a third embodiment of the present invention.

FIG. 7 is an explanatory diagram of a conventional transformer soundproof structure.

[Explanation of symbols]

1 ... Main body tank, 2 ... Sound barrier, 3 ... Opening part, 4, 11 ...
Sound absorbing material, 5 ... Bushing, 6a, 6b ... Speaker, 7 ...
Acceleration sensor, 8a, 8b, 8c ... Microphone, 9
a-9f ... Control cable, 10 ... Control device, 12 ... V-shaped part, 13 ... Arc-shaped part, 14 ... Space, 15 ... Partition, 16 ... Area.

Continued front page    (72) Inventor Hiroshi Muramatsu             2-1, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa             Ceremony Company Toshiba Hamakawasaki Factory F-term (reference) 5E058 AA05 AA15                 5E059 BB04 BB17 LL03 LL07

Claims (6)

[Claims] 1. A transformer main body including an iron core, a coil, etc., a main body tank accommodating the transformer main body, a soundproof wall provided so as to surround a side surface of the main body tank, and having an opening formed in an upper portion thereof. An acoustic sensor that detects the noise of the transformer body, an acoustic generator that is placed at a position that generates a noise that cancels the noise, and an acoustic generation that corresponds to the noise level detected by the acoustic sensor. A transformer consisting of a control device that controls to generate a sound that cancels noise from the device. 2. The transformer according to claim 1, wherein a sound absorbing material for preventing reflection is attached to at least one of the main body tank and the soundproof wall of the transformer. 3. The transformer according to claim 1, wherein the shape of the upper end of the soundproof wall provided around the side surface of the main body tank of the transformer is substantially V-shaped. 4. The transformer according to claim 1, wherein the shape of the upper end of the soundproof wall provided around the side surface of the main body tank of the transformer is a substantially arc shape. 5. A partition for partitioning a space between the soundproof wall and the main body tank along the circumferential direction of the main body tank is provided on the inner surface of the soundproof wall. The listed transformer. 6. A partition for partitioning the space between the soundproof wall and the main body tank along the circumferential direction of the main body tank is provided on the inner surface of the soundproof wall, and the interval between the partitions is about 1/2 of the wavelength of noise or less. The transformer according to any one of claims 1 to 4, wherein: