Patent Description:
As illustrated in <FIG>, an internal space 11a is provided inside a tank <NUM> forming an outer appearance of a conventional transformer <NUM>, and the internal space 11a is provided with a core <NUM> and a winding <NUM>, wound around the core. The internal space 11a may be filled with oil, an insulating fluid.

Vibrations of the core <NUM> and the winding <NUM> may occur inside the tank <NUM> of the transformer <NUM>, and the vibrations may be transmitted to the tank <NUM> of the transformer through a mechanical structure of the transformer and the insulating fluid.

In such a process, acoustic sound may be generated, and the generated acoustic sound may be transmitted to a periphery of the transformer <NUM> as noise.

Therefore, there is a need for research on noise reduction, optimized for various designs, standards, and mechanical specifications of the transformer.

Patent document <CIT>, disclose an arrangement for reducing the radiation of noise from liquid-cooled transformers or chokes including a tank having stiffeners arranged outside on the side walls of the tank, where a region situated between each stiffener is covered by a sandwich panel that is fastened to each stiffener.

Patent document <CIT>, discloses a transformer case noise reduction device for setting up the noise reduction device outside the container installed around the transformer and reducing the noise radiated through the transformer to the outside of the container.

Patent document <CIT>, discloses stationary inductance electrical appliance and low frequency sound absorbing wall.

Patent document <CIT>, discloses stationary induction apparatus assembly to reduce noise generation in a closed vessel, relating to a stationary induction apparatus where insulating medium such as oil is sealed up in the closed vessel.

An aspect of the present disclosure is to reduce noise of a transformer.

In addition, an aspect of the present disclosure is to reduce noise in a manner optimized for characteristics of a transformer.

According to an aspect of the present disclosure, a soundproofing transformer is provided, as summarized in independent claim <NUM>.

According to the present disclosure, it is possible to reduce noise of a transformer.

In addition, noise may be reduced in a manner optimized for characteristics of the transformer.

In order to facilitate understanding of the description of the embodiments of the present disclosure, elements denoted by the same reference numerals in the accompanying drawings are the same element, and among the constituent elements which perform the same function, the related constituent elements are indicated by the number on the same or an extension line.

In order to clarify the gist of the present disclosure, descriptions of elements and techniques well known in the related art will be omitted, and the present disclosure will be described in detail with reference to the accompanying drawings.

It is to be understood that the present disclosure may, however, be exemplified in many different forms and should not be construed as being limited to specific embodiments set forth herein, but may be suggested by those skilled in the art in other forms in which certain elements are added, alternated, and deleted.

In <FIG>, a soundproofing transformer <NUM> is illustrated in an embodiment of the present disclosure.

The soundproofing transformer <NUM> according to an embodiment of the present disclosure may include a tank <NUM>, a winding portion <NUM> and a core portion <NUM> provided inside the tank, an insulating fluid provided inside the tank, a reinforcing member <NUM> provided outside of the tank, a cavity <NUM> having a resonance space <NUM> and connected to the reinforcing member <NUM> by a coupling member <NUM>, a partition member <NUM> stacked on the cavity <NUM> and having an acoustic absorption space <NUM>, a noise inlet member <NUM> having a first inlet <NUM> facing the tank <NUM> and connected to the resonance space <NUM> to transmit noise introduced from the first inlet <NUM> to the resonance space <NUM>, and a noise reduction panel <NUM> connected to at least one of the partition member <NUM> and the noise inlet member <NUM> and having a second inlet <NUM> provided to communicate with the acoustic absorption space <NUM> while facing the tank <NUM>.

In the soundproofing transformer according to an embodiment of the present disclosure, as illustrated in <FIG>, the noise reduction panel <NUM> may be coupled to the reinforcing member <NUM> so as to face the tank <NUM> or the noise reduction panel <NUM> may be spaced apart from the reinforcing member <NUM> by a predetermined distance so as to face the reinforcing member <NUM> and the tank <NUM>. The tank <NUM> of transformer may have a space 210a for accommodating an insulating fluid.

In the soundproofing transformer according to an embodiment of the present disclosure, as illustrated in <FIG>, the cavity <NUM> may be coupled to the reinforcing member <NUM> by using the coupling member <NUM> such that the cavity <NUM> is interposed between the reinforcing members <NUM>.

In a soundproofing transformer according to another embodiment of the present disclosure, as illustrated in <FIG>, the noise reduction panel <NUM> may be coupled to the reinforcing member <NUM> by using the coupling member <NUM>, such that the cavity <NUM> covers the reinforcing member <NUM>.

Meanwhile, as illustrated in <FIG>, the cavity <NUM> may be placed to be spaced apart from the tank <NUM> and the reinforcing member <NUM> by a predetermined distance, and these various installation methods may be suitably selected and applied depending on characteristics of the transformer, service environments of the transformer, and the like.

A configuration for reducing noise in the present disclosure, as illustrated in <FIG>, may include a cavity <NUM> having a resonance space <NUM> having a constant volume, a noise inlet member <NUM> connected to the cavity <NUM> to communicate with the resonance space <NUM>, and a noise reduction panel <NUM> connected to at least one of the cavity <NUM> and the noise inlet member <NUM> and having at least one second inlet <NUM> facing the tank (<NUM> of <FIG>).

When describing an embodiment of the present disclosure with reference to <FIG> in more detail, the noise inlet member <NUM> may include a hollow portion <NUM> therein, and both end portions of the noise inlet member <NUM> may be opened.

In this case, a side, in which the noise inlet member <NUM> faces the tank (<NUM> of <FIG>) of the transformer, is a first inlet <NUM> through which noise is introduced.

The hollow portion <NUM> may be continuous with the first inlet <NUM>, and may be continuously provided in a longitudinal direction of the noise inlet member <NUM>. A diameter of the hollow portion <NUM> may be constant in the longitudinal direction of the noise inlet member <NUM>.

A region of the noise inlet member <NUM> in which the first inlet <NUM> is present may be connected to the noise reduction panel <NUM>, and the other side of the noise inlet member <NUM> may be connected to the cavity <NUM>.

In connecting the noise inlet member <NUM> and the cavity <NUM>, the noise inlet member <NUM> is connected to the cavity <NUM> such that the hollow portion <NUM> of the noise inlet member <NUM> is connected to the resonance space <NUM>.

The hollow portion <NUM> of the noise inlet member <NUM> may be connected to the resonance space <NUM> and may simultaneously also be provided to communicate with an outside of the cavity <NUM> and an outside of the noise reduction panel <NUM>.

Therefore, the noise inlet member <NUM> may be a path through which noise is introduced to the resonance space <NUM> of the cavity <NUM>.

The resonance space <NUM> of the cavity <NUM> may be filled with air, and the air present in the resonance space <NUM> may act as a spring to cause resonance at a specific frequency. Therefore, noise introduced into the resonance space <NUM> may be reduced.

Specifically, when resonance of the air present in the resonance space <NUM> of the cavity <NUM> occurs, a fluid (for example, air) may actively flow in and out through the first inlet <NUM> and the hollow portion <NUM> of the noise inlet member <NUM>, and in this case, the fluid may rub against a tube wall of the noise inlet member <NUM> to generate thermal energy, thereby allowing acoustic absorption.

Meanwhile, the second inlet <NUM> may be a hole penetrating the noise reduction panel <NUM> in a direction parallel to the hollow portion <NUM>.

The plurality of the second inlets <NUM> may be provided on the noise reduction panel <NUM>, and an inner diameter of the second inlet <NUM> may be measured in micrometer units.

In addition, since the noise blocking performance, that is, the frequency at which resonance is possible, may be adjusted by altering an inner diameter of the second inlet <NUM>, the size of inner diameter of the second inlet <NUM> may be appropriately selected depending on operators and work environments and applied, but is not necessarily limited to that of the present disclosure.

The second inlet <NUM> may cause thermal losses and viscous losses of sound waves generated by noise with a wall surface of the noise reduction panel <NUM>, thereby weakening noise.

The thermal losses and the viscous losses of the sound waves may occur in thermal and viscous boundary layers near the wall surface of the noise reduction panel <NUM>.

Therefore, as the number of the second inlet <NUM> increases and the diameter of the second inlet <NUM> decreases, an acoustic absorption effect may increase.

Therefore, in another embodiment of the present disclosure, as illustrated in <FIG>, a noise inlet hole <NUM> having a diameter in a micrometer unit may be formed on one surface of the cavity <NUM> facing the noise reduction panel <NUM>, thereby further increasing the acoustic absorption effect as described above.

In an embodiment of the present disclosure, the noise inlet hole <NUM> may be a hole penetrating the cavity <NUM> in a direction parallel to the hollow portion <NUM> of the noise inlet member <NUM>.

In this case, the noise inlet hole <NUM> may be a hole penetrating one surface of the cavity <NUM> to be connected to the resonance space <NUM> inside the cavity.

Further, the noise inlet hole <NUM> may be provided in a slot shape other than holes.

Meanwhile, the partition member <NUM> according to the present disclosure may serve to connect the cavity <NUM> and the noise reduction panel <NUM>, and to separate the noise reduction panel <NUM> from the cavity <NUM>.

The partition member <NUM> may be disposed outside of the outer peripheral surface of the noise inlet member <NUM>, the first inlet <NUM>, the second inlet <NUM>, and the noise inlet hole <NUM> to form the acoustic absorption space <NUM> on the outer peripheral surface of the noise inlet member <NUM>.

Accordingly, the partition member <NUM> may be provided to surround the noise inlet member <NUM>.

The fluid present in the acoustic absorption space <NUM> may also act as a spring to contribute to increasing the acoustic absorption effect on the same principle as described above.

Further, as illustrated in <FIG>, when the acoustic absorption space <NUM> is provided with a porous acoustic absorption material <NUM>, the acoustic absorption effect may be further increased and the noise may be significantly reduced.

A material of the porous acoustic absorption material <NUM> may be glass fiber, open-cell foam, felted or cast porous ceiling tile, or the like, however, the material is not necessarily limited to the present disclosure.

Meanwhile, the plurality of noise inlet members <NUM> may be provided in the cavity <NUM>, and the outer peripheries of the noise inlet members <NUM> may be spaced apart from each other by a predetermined distance.

The number of the noise inlet member <NUM> and the distance in which the noise inlet members <NUM> are spaced apart may be suitably set based on a frequency at which the resonance space <NUM> of the cavity <NUM> resonates. In this case, the frequency at which the resonance space <NUM> resonates may be generated by noise.

As illustrated in <FIG>, in another embodiment of the present disclosure, the cavity may have a cylindrical form, such that the resonance space <NUM> of the cavity <NUM> may also have a cylindrical form.

In this case, the volume (V) of the resonance space of the cavity, the length (L) of the noise inlet member <NUM>, and the cross-sectional area (A) of the inner diameter of the noise inlet member <NUM> may be determined by a resonance frequency (fH)of the fluid present in the resonance space <NUM>.

A relationship between the resonance frequency (fH, hz) and the volume (V) of the resonance space, the length (L) of the noise inlet member <NUM>, and the cross-sectional area (A) of the inner diameter of the noise inlet member <NUM> is expressed by the following Equations <NUM> and <NUM>.

The Equations <NUM> and <NUM> are relational expressions necessary for deriving the resonance frequency (fH). The resonance frequency (fH) may be generated by noise, and a numerical value thereof may also be determined by noise. <MAT><MAT>.

In the accompanied Equations <NUM> and <NUM>, γ is an adiabatic index, P<NUM> is pressure of the resonance space (<NUM> of <FIG>), of the cavity, and ρ is a mass density of a fluid (for example, air) present in the resonance space (<NUM> of <FIG>) of the cavity.

Therefore, the specification of the volume (V) of the resonance space of the cavity, the length (L) of the noise inlet member <NUM>, and the cross-sectional area (A) of the inner diameter of the noise inlet member <NUM> may be determined according to the rated frequency of the transformer, that is, the noise caused from the transformer.

A value of the rated frequency of the transformer may be substituted into a value of the resonance frequency(fH)of the Equations expressed in Equations <NUM> and <NUM> to determine the volume (V) of the resonance space of the cavity, the length (L) of the noise inlet member <NUM>, the cross-sectional area(A) of the inner diameter of the noise inlet member <NUM>, that is, the cross-sectional area of the hollow portion <NUM>.

The volume (V) of the resonance space <NUM> of the cavity <NUM> and the length (L) of the noise inlet member <NUM>, illustrated in <FIG> are Vo and Leq in Equation <NUM>, respectively. When calculating by substituting the resonance frequency (fH) into the Equation expressed Equation <NUM>, A = A of <FIG>, Leq= L of <FIG>, Vo= V of <FIG>, and the rated frequency of transformer may be substituted into the resonance frequency (fH) to be calculated.

That is, specifications of the cavity <NUM> and the noise inlet member <NUM> may be derived by using the Equations expressed in Equations <NUM> and <NUM> with a rated frequency value generated by the transformer.

For example, when the transformer having a rated frequency of <NUM> is applied, volumes of first and second resonance spaces 111a and 111b of <FIG> may be calculated by the above formula expressed in Equations <NUM> and <NUM>.

The specification relating to the noise inlet member <NUM> derived from the Equation <NUM> may be a specification relating to any one of three noise inlet members <NUM> connected to the second resonance space <NUM>1b, and the volume of the noise inlet member <NUM> penetrating the second resonance space 111b and the acoustic absorption space <NUM> and connected to the first resonance space 111a, may be ignored when calculating the volume of the first resonance space 111a and the second resonance space 111b. Heights of the first and second resonance spaces 111a and 111b may be equal to each other.

In an embodiment of the present disclosure, dimensions in <FIG> may be as follows, B=<NUM>, C=<NUM>, D=<NUM>, E=<NUM>, and F=<NUM>.

In another embodiment of the present disclosure, when a transformer having a rated frequency of <NUM> is applied, as illustrated in <FIG>, the volume of the second resonance space 111b may be ignored when calculating the volume of the first resonance space 111a, and specifications of the noise inlet members <NUM> connected to the first resonance space 111a and the second resonance space 111b may be equal to each other.

However, the volume of the second resonance space 111b is not specified by the present disclosure. The volume of the second resonance space 111b may be suitably selected and applied by those skilled in the art in consideration of the rated frequency of the transformer and the service environment of the transformer.

For example, dimensions in <FIG> may be as follows, B=<NUM>, C=<NUM>, D=<NUM>, E=<NUM>, and F=<NUM>.

However, these are only one example, and the detailed specifications may be determined by the transformer (or an environment generating noise).

Meanwhile, a sound wave absorption coefficient according to a frequency of a noise reduction apparatus according to <FIG> is illustrated in <FIG>.

Referring to <FIG>, it can be confirmed that a noise reduction panel <NUM> having the second inlet <NUM> and the noise inlet hole <NUM> (double MPP) and a cavity <NUM> has a significantly increased sound wave absorption coefficient in a section of <NUM> to <NUM>, such that the noise blocking effect is further improved as compared with a noise reduction panel <NUM> having only the second inlet <NUM> (single MPP).

Meanwhile, as described above, the cavity <NUM> illustrated in <FIG> may include a first cavity <NUM> having a first resonance space 111a and to which the noise inlet member <NUM> is connected, and a second cavity <NUM> having a second resonance space 111b separated from the first resonance space 111a, stacked on an upper portion of the first cavity <NUM> and to which a plurality of noise inlet members <NUM> are connected.

In this case, the plurality of noise inlet members <NUM> connected to the second cavity <NUM> to communicate with the second resonance space 111b may be connected to the second cavity <NUM> through the acoustic absorption space <NUM>.

The noise inlet member <NUM> connected to the first resonance space 111a may be connected to the noise reduction panel <NUM> through the second resonance space 111b and the acoustic absorption space <NUM>.

Accordingly, noise may be reduced in various frequency areas while suppressing an increase in the width of the cavity <NUM>, and utilization of space may be improved.

As another aspect, as illustrated in <FIG>, the cavity <NUM> may include a first cavity <NUM> having a first resonance space 111a and to which the plurality of noise inlet members <NUM> are connected, and a second cavity <NUM> having a second resonance space <NUM>1b separated from the first resonance space 111a and accommodated in the first resonance space 111a.

In this case, the noise inlet member <NUM> connected to the second cavity <NUM> to communicate with the second resonance space 111b may be connected to the noise reduction panel <NUM> through the acoustic absorption space <NUM>.

By providing the cavity <NUM> in plural, utilization of space may be increased and noise may be reduced in various frequency areas.

Further, as illustrated in <FIG>, a cavity <NUM> having a matrix structure may be provided.

This makes it possible to easily install the cavity <NUM> and the noise inlet member <NUM> having a resonance frequency equal to the rated frequency of the transformer, and the cavity <NUM> and the noise inlet member <NUM> may be modularized according to the specification of the transformer, thereby further improving convenience in use.

In an embodiment of the present disclosure, the cavity <NUM> may include a first cavity <NUM> and a second cavity <NUM> having resonance spaces <NUM>.

More specifically, the cavity <NUM> may include a first cavity <NUM> having a first resonance space 111a, and a second cavity <NUM> having a second resonance space 111b.

A noise inlet member <NUM> may be connected to the first cavity <NUM> and the second cavity <NUM>, respectively, and a hollow portion <NUM> of the noise inlet member <NUM> may be connected to the first resonance space 111a and the second resonance space 111b, respectively.

In this case, the first resonance space <NUM>1a of the first cavity <NUM> and the second resonance space 111b of the second cavity <NUM> may be separated or may not be separated from each other.

To this end, in an embodiment of the present disclosure, the first cavity <NUM> and the second cavity <NUM> may include a connection hole <NUM>, respectively, as illustrated in <FIG>. More specifically, the connection hole <NUM> may include a first connection hole 115a formed on a surface of the first cavity <NUM> facing the second cavity <NUM>, and a second connection hole 115b formed on a surface of the second cavity <NUM> facing the first cavity <NUM>.

A cover member <NUM> may be provided to be coupled to or be uncoupled from the connection hole <NUM> such that the first cavity <NUM> and the second cavity <NUM> may be connected to or separated from each other.

The cover member <NUM> may be provided to be coupled to the connection hole <NUM> by a bolt, or the like, and may be coupled to the connection hole <NUM> by a fitting tolerance with the connection hole <NUM>.

According to the connection hole <NUM> and the cover member <NUM>, the volume of the cavity <NUM> may be easily changed, and the convenience and speed of operation in the field may be improved.

In addition, a first noise inlet member <NUM> may be connected to the first cavity <NUM> to communicate with the first resonance space 111a, and a second noise inlet member <NUM> may be connected to the second cavity <NUM> to communicate with the second resonance space 111b.

The first and second cavities <NUM> and <NUM> and the noise reduction panel <NUM> are connected to each other even when the connection hole <NUM> is formed in the cavity <NUM>, and a partition member <NUM> in which the noise reduction panel <NUM> is spaced apart from the first and second cavities <NUM> and <NUM> to form an acoustic absorption space <NUM> between the noise reduction panel <NUM> and the first and second cavities <NUM> and <NUM> may be provided.

In this case, the acoustic absorption space <NUM> may be provided with a porous sound absorption material (<NUM> of <FIG>) to further improve the noise reduction effect.

In addition, in an embodiment of the present disclosure, as illustrated in <FIG>, the cavities <NUM> may be stacked in plural and modulated.

Accordingly, it is possible to easily adjust the specification of the cavity <NUM> according to the specification of the transformer.

Claim 1:
A soundproofing transformer, comprising:
a tank (<NUM>);
a winding portion (<NUM>) and a core portion (<NUM>) provided inside the tank; and
an insulating fluid provided inside the tank,
a reinforcing member (<NUM>) provided outside of the tank;
a cavity (<NUM>) having a resonance space (<NUM>) and connected to the reinforcing member (<NUM>) by a coupling member (<NUM>);
a partition member (<NUM>) stacked on the cavity (<NUM>) and forming an acoustic absorption space (<NUM>), characterized in that the soundproofing transformer further comprises,
a noise inlet member (<NUM>) having a first inlet (<NUM>) facing the tank, connected to the cavity (<NUM>) through the acoustic absorption space (<NUM>), and configured to transmit noise introduced from the first inlet (<NUM>) to the resonance space (<NUM>), and
a noise reduction panel (<NUM>) connected to the partition member (<NUM>) and the noise inlet member (<NUM>), and having a second inlet (<NUM>) provided to communicate with the acoustic absorption space (<NUM>) while facing the tank, and
wherein the partition member (<NUM>) connects the cavity (<NUM>) and noise reduction panel (<NUM>), and is provided to separate the noise reduction panel (<NUM>) from the cavity (<NUM>).