KR100470910B1 - A noise reduction transformer - Google Patents

Abstract

The present invention relates to a transformer that reduces noise, the present invention is installed in the enclosure, the assembly consisting of an iron core and a winding, an upper frame coupled to the upper end of the iron core to tighten the upper portion of the iron core, the iron core A lower frame coupled to a lower end and tightening a lower portion of the iron core, respectively installed between both inner walls of the enclosure and the upper frame to support the assembly to the enclosure and to attenuate vibration transmitted from the assembly to the enclosure; It is configured to include a support and vibration damping means, to effectively attenuate both high frequency and low frequency vibration of the audio frequency band transmitted from the assembly to the transformer enclosure to reduce the noise of the audio frequency band.

Description

Noise reduction transformer {A noise reduction transformer}

TECHNICAL FIELD The present invention relates to a transformer, and more particularly, to a noise reduction transformer suitable for reducing noise by effectively attenuating both high frequency and low frequency vibrations in an audio frequency band transmitted from a core and coil assembly to a transformer enclosure.

In general, the transformer refers to a device for changing the value of the AC voltage using the electromagnetic induction action, there are many kinds, ranging from power transformers and coupling transformers used in electronic circuits.

Among the various transformers, the distribution transformer that converts the high voltage sent from the substation into the low voltage of factory or home is installed in the vicinity of the electric poles. Widely used.

1 is a cross-sectional view for explaining the configuration of a conventional distribution transformer.

As shown, the conventional transformer is an enclosure 101, an assembly 107 (core and coil assembly) which is installed in the enclosure 101, consisting of an iron core (103, core) and a winding (105, coil), Support means for supporting the assembly 107 to the enclosure 101 is installed between the upper and lower frames, the upper and lower frames coupled to the iron core 103, the lower inner side of the enclosure 101 and the upper frame ( 113).

However, according to the configuration of the conventional transformer, when the iron core 103, which is usually made of silicon steel and becomes ferromagnetic, vibrates due to magnetostriction, the vibration is transmitted through the support means 113. As it is delivered to the enclosure 101, the enclosure 101 is also vibrated.

As such, when the enclosure 101 of the transformer vibrates, waves due to the vibration are transmitted to the person using air as a medium, among which waves belonging to the audible frequency band act as a considerable noise while being sensed by hearing.

Therefore, conventional transformers are mostly installed in the residential area, and do not meet the needs of the residents to have a comfortable and comfortable living space, causing serious noise problems, there was a problem that is not environmentally friendly.

Of course, in recent years, technology development has been made to prevent vibration and noise problems caused by transformers, but it has been concentrated on power transformers such as large capacity and ultra high pressure and is not applicable to power distribution transformers.

This is because the vibration of the audible frequency band generated from the iron core 103 of the transformer is widely distributed over both the high frequency and low frequency bands, and thus only attenuates the vibration of any of the high frequency or low frequency bands, so that the noise problem is not solved. This is because the simple configuration without the burden of cost increase is difficult to solve the problem.

Even the fact that the vibration generated in the iron core 103 of the transformer is distributed over both high frequency and low frequency bands is often unknown, which makes it difficult to fundamentally solve the noise problem.

On the other hand, conventionally, as the mechanical tightening state is loosened in the support means 113 connecting the assembly 107 and the enclosure 101 over time, the noise problem is worse.

That is, when the mechanical tightening state is loosened in the support means 113, the enclosure 101 is further vibrated due to an unbalance of the excitation force and the support force, thereby causing more severe noise. .

Accordingly, the present invention has been proposed to solve the above-mentioned conventional problems, and an object of the present invention is to effectively attenuate both high and low frequency vibrations of the audible frequency band transmitted from the assembly to the transformer enclosure without complicated vibration damping devices. Therefore, to provide a noise reduction transformer that suppresses the generation of noise.

It is still another object of the present invention to provide a noise reduction transformer which prevents the mechanical tightening between the enclosure and the assembly over time.

Noise reduction transformer according to the technical idea of the present invention for achieving the above object, the upper part which is installed in the enclosure, the assembly consisting of iron core and winding, and coupled to the upper end of the iron core to tighten the upper part of the iron core. A frame, a lower frame coupled to a lower end of the iron core and tightening the lower portion of the iron core, respectively installed between both inner walls of the enclosure and the upper frame to support the assembly to the enclosure, and to be transmitted from the assembly to the enclosure. It is characterized by the technical configuration that comprises a first support and a vibration damping means for attenuating the.

Here, the first support and vibration damping means, a fixing nut fixed to the inner wall of the enclosure, a support bolt that is horizontally fastened to the fixing nut, coupled to the upper frame and fitted to the support bolt to the assembly A connection piece supporting the support bolt, the NBR packings fitted to the support bolts, respectively installed on both sides of the connection piece, a spring fitted to the support bolts, and installed between the fixing nut and the NBR packing, and the support bolts. The fastening nut is preferably configured to include a tightening nut fastened to the connecting piece, the NBR packing and the spring toward the fixing nut.

In addition, the spring is preferably a dish spring.

In addition, the second support and vibration damping means which is installed between the bottom of the enclosure and the lower frame, and attenuates the vibration transmitted from the assembly to the bottom of the enclosure while supporting the assembly further includes any one of cork packing or NBR packing. Can be.

Hereinafter, an embodiment according to the spirit of the present invention as described above will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view for explaining the configuration of the noise reduction transformer of the present invention.

As shown, the present invention comprises an enclosure 1, an assembly 7, an upper frame 9, a lower frame 11, and first support and vibration damping means 13.

Here, the assembly 7, the core and coil assembly, is installed in the enclosure 1 and consists of an iron core 3, a core, and a winding 5.

The enclosure 1 is also filled with a sufficient amount of insulating oil to immerse the assembly 7.

In addition, the upper frame 9 is coupled to the upper end of the iron core (3).

Here, the upper frame 9 is coupled to tighten the upper portion of the iron core (3).

In addition, the lower frame 11 is coupled to the lower end of the iron core (3).

Here, the lower frame 11 is coupled to tighten the lower portion of the iron core 3 like the upper frame 9.

As such, when the upper frame 9 and the lower frame 11 tighten the iron core 3, the vibration of the iron core 3 is slightly attenuated.

 In addition, the first support and vibration damping means 13 is installed between the inner wall of the enclosure 1 and the upper frame 9, two or more are installed in a symmetrical position around the assembly (7) do.

As a result, the first support and vibration damping means 13 support the assembly 7 having a high load in a balance with the enclosure 1, and at the same time, the vibration transmitted from the assembly 7 to the enclosure 1. Effectively attenuates

Hereinafter, the configuration of the first support and vibration damping means 13 will be described in more detail.

FIG. 3 is a reference view showing A of FIG. 2 to explain the configuration of the first support and vibration damping means, FIG. 4 is an exploded perspective view of the first support and vibration damping means of the present invention, and FIG. Side cross-sectional view showing the shape of two dish springs superimposed in series.

As shown, the first support and vibration damping means 13 of the present invention, the fixing nut 15, the support bolt 17, the connecting piece 19, the NBR packing (21, Nitrile Butadiene Rubber Packing), The spring 23 and the fastening nut 25 are comprised.

Here, the fixing nut 15, the support bolt 17, and the connecting piece 19 support the assembly 7 having a high load while connecting the enclosure 1 and the assembly 7 to the enclosure 1. Done.

Therefore, the fixing nut 15, the support bolt 17 and the connecting piece 19 should be firmly installed between the enclosure (1) and the assembly (7).

To this end, the fixing nut 15 is firmly fixed to the enclosure 1 to sustain the load of the assembly 7.

In addition, the support bolt 17 is horizontally fastened to the fixing nut 15, and the support bolt 17 to continuously withstand the load of the assembly 7 in a state that is fastened to the fixing nut 15. ) Is fastened without shaking.

In addition, the connecting piece 19 is fitted to the support bolt 17 in a state coupled to the upper frame (9).

Here, the connecting piece 19 is formed of a "b" shaped structure having a through hole through which bolts can be formed on each side, and one side is fitted to the support bolt 17 by the through hole formed on each side, and the other side is The upper frame 9 is coupled to and fixed to the upper surface.

Here, a conventional bolt, washer, etc. are used to couple the connecting piece 19 and the upper frame 9 to each other.

On the other hand, the connecting piece 19 may be formed in a straight shape not shown as well as "b" shape, in addition, it may be formed in various forms that can easily connect the support bolt 17 and the upper frame (9). Of course.

In this case, when the connecting piece 19 is formed in a straight shape, the connecting piece 19 is appropriately coupled to the side of the upper frame 9, not the upper surface.

 In addition, the NBR packing 21 is fitted to the support bolt 17, it is located on both sides of the connecting piece (19).

Here, the NBR packing 21 attenuates the vibration transmitted from the assembly 7 to the enclosure 1 without melting in the insulating oil filled in the enclosure 1.

In particular, the NBR packing 21 serves to effectively attenuate the vibration of the high frequency band among the vibrations of the audible frequency band transmitted from the assembly 7 to the enclosure 1, which will be described in detail later.

In addition, the spring 23 is fitted to the support bolt 17 like the NBR packing 21 and is installed between the fixing nut 15 and the NBR packing 21.

Here, the spring 23 is composed of a plate spring (23, Belleville spring) having a plate head or a cone with a through-hole formed in the center.

Since the plate spring 23 has a merit that can store a lot of energy while being installed in a relatively small space as already known, it is installed in a narrow space between the fixing nut 15 and the NBR packing 21 The NBR packing 21 is suitable for damping the vibration applied to the fixing nut 15 and mitigating the impact.

In addition, the dish spring 23 may be used alone, or two or more may be used in series or in parallel.

Thus, referring to Figure 5 it can be seen a configuration in which the plate spring 23 is superimposed in series.

Here, the dish spring 23 is suitable for use in an environment in which a higher load is applied when overlapped in the same direction as shown in FIG. 5 (a), while a lower load is applied when overlapped as in (b). It is suitable for use in the applied environment and has a large displacement and is sensitive.

As such, the dish spring 23 is provided with a single or a plurality of overlapping to suit the situation to reduce the vibration.

In particular, the dish spring 23 serves to attenuate the vibration of the low frequency band. This will be described later in detail.

Thus, the NBR packing 21 and the dish spring 23 cooperate with each other to attenuate both high frequency and low frequency vibrations in the audible frequency band transmitted from the assembly 7 to the enclosure 1.

In addition, the tightening nut 25 is fastened to the support bolt 17, and the connecting nut 19, the NBR packing 21, and the dish spring 23 fitted to the support bolt 17 are fixed to the fixing nut ( Tightens toward 15).

Here, the tightening nut 25 is not loosened due to the impact caused by the vibration continuously transmitted from the assembly 7 over time.

This is because the NBR packing 21 and the dish spring 23 have a buffering effect to alleviate or absorb shocks caused by vibrations transmitted from the assembly 7.

As a result, the conventional mechanical connection part for the support between the assembly 7 and the enclosure 1 is loosened, thereby solving the problem of the enclosure 1 vibrating violently.

Meanwhile, it is preferable that flat washers 27a and 27b are inserted between the dish spring 23 and the NBR packing 21 and between the NBR packing 21 and the tightening nut 25.

The flat washers 27a and 27b provided as described above, when the tightening nut 25 tightens the connecting piece 19, the NBR packing 21, and the dish spring 23 toward the fixing nut 15, The NBR packing 21 is prevented from being damaged and contact friction is reduced to facilitate rotation of the tightening nut 25.

In addition, the bottom portion of the body supports the assembly 7 together with the first support and vibration damping means 13 and a second support to attenuate the vibration transmitted from the assembly 7 to the enclosure 1. And vibration damping means 29 are further provided.

6 is a cross-sectional view of the present invention in which the second support and vibration damping means are adopted.

As shown, the second support and vibration damping means 29 has a wide panel form and is fitted between the bottom of the enclosure 1 and the lower frame 11.

In this case, the second support and vibration damping means 29 is provided with either a wide panel form cork packing or NBR packing.

Here, the NBR packing has a characteristic of effectively attenuating high frequency vibration among vibrations of an audible frequency band transmitted from the assembly 7 to the enclosure 1 as described above.

In addition, the cork packing, like the NBR packing, has a characteristic of effectively attenuating high frequency vibration without melting in insulating oil, and is suitable for supporting a high load object such as the assembly 7.

As such, the second support and vibration damping means 29 together with the first support and vibration damping means 13 support the assembly 7 to the enclosure 1 and at the same time the assembly 7 ) To attenuate the high frequency vibration of the audible frequency band transmitted to the enclosure (1) more stably.

Hereinafter, the vibration reduction of the enclosure 1 which causes noise in the noise reduction transformer and the conventional transformer of the present invention will be measured and described. This is only to illustrate the present invention and does not limit the scope of the present invention.

In this experiment, however, the effect of harmonics with the fundamental frequency of 120 [Hz] was the greatest. Therefore, the following tables describe the vibration frequency values centering on the harmonic periods with the fundamental frequency of 120 [Hz]. Say.

The conditions for this experiment are as follows.

First, the device for this experiment consisted of a return load device, a 100 [mV / g] high sensitivity acceleration sensor from Wicoxon Research, and a vibration frequency measurement device.

Here, the acceleration sensor is installed on a cover covering the outer wall of the enclosure (1) and the enclosure (1).

In addition, in order to convert the magnetic flux density of the transformer, the voltage of the induction voltage regulator (IVR) for the iron loss supply is varied to 207V, 230V, 253V and 279V, which is 90%, 100%, 110% and 120% of the rated voltage. The oscillation frequency was measured while varying the rated load flowing to 65A and 130.4A, which were 50% and 100% of the rated load.

In addition, when the insulating oil filled in the enclosure 1 is room temperature (Table 1a, Table 2a, Table 3a), and when the temperature of the insulating oil is not saturated anymore (Table 1b, Table 2b, Table 3b) The vibration frequency was measured by dividing each.

First, Table 1a below describes the measured values of vibration frequencies transmitted from the assembly 107 to the enclosure 101 in a conventional transformer when the insulating oil is at room temperature, and Table 1b shows the conventional values when the insulating oil is saturated. It describes the measured value of the vibration frequency transmitted from the assembly 107 to the enclosure 101 in the transformer of.

7A and 7B are graphs based on the numerical values of Tables 1A and 1B.

120 240 360 480 600 720 840 980 1080 1200 1320 1460 1580 1700 1820 1960 2080 Current 50, Voltage 90 1.3 0.85 2.05 0.5 0.25 0.1 0.2 0.1 0.8 1.45 1.95 0.2 0.4 0.15 0.2 0.25 0.1 Current 50, Voltage 100 1.75 One 4.05 One 0.5 0 0.3 0.2 1.1 2.1 1.9 0.4 0.5 0.5 0.2 0.2 0.2 Current 50, Voltage 110 2.2 1.5 5.4 1.4 1.6 0.4 0.2 0 0.6 1.4 2.9 0.8 One 0.3 0.4 0.3 0 Current 50, Voltage 120 2.3 1.6 6.5 3.2 1.8 0.3 0.4 1.05 0.2 0.4 1.6 0.2 2.1 0.6 1.8 1.8 0 Current 50, Voltage 90 2.5 0.75 2.1 0.45 0.1 0 0 0.1 0.7 1.9 1.4 0.3 0.4 0.1 0.2 0.3 0.1 Current 100, Voltage 100 1.25 2.5 3.9 0.8 0.4 0 0 0.3 1.2 1.75 2.45 0.5 0.5 0.1 0.25 0.3 0.1 Current 100, Voltage 110 0.9 1.6 4.9 1.1 1.5 0.25 0.1 0.2 0.8 2.2 3.5 0.7 1.3 0.2 0.2 0.2 0 Current 100, Voltage 120 1.2 1.3 8 4.1 1.1 One 0.9 1.8 0.3 1.2 2 0.2 1.2 0.8 3 1.8 0.2

120 240 360 480 600 720 840 980 1080 1200 1320 1460 1580 1700 1820 1960 2080 Current 50, Voltage 90 1.72 1.3 1.72 0.6 0.1 0.3 0.1 0.4 0.65 1.2 0.4 0.35 0.43 0.1 0.3 0.15 0.1 Current 50, Voltage 100 1.9 0.8 3.1 0.65 0.35 0.2 0.1 0.8 0.6 1.4 0.7 0.35 0.7 0.1 0.2 0.2 0 Current 50, Voltage 110 2.35 2.8 3.75 One 0.8 0.2 0.1 0.4 0.2 One 1.35 0.3 1.3 0.6 0.3 0.3 0.1 Current 50, Voltage 120 3.2 2.8 7.8 4 1.2 1.3 0.1 2.8 0.7 1.6 0.9 0.5 1.7 0.5 2.5 1.7 0.5 Current 50, Voltage 90 0.27 One 1.2 0.37 0 0.36 0 0.1 0.4 1.55 0.32 0.18 0.56 0 0.22 0.1 0.1 Current 100, Voltage 100 0.3 1.4 2.25 0.6 0.3 0.4 0 0.6 0.7 1.2 0.45 0.2 0.4 0 0.3 0.1 0 Current 100, Voltage 110 1.1 2.6 2.7 0.9 One 0.2 0.4 0.1 0.5 One 0.8 0.25 2.3 0.75 0.45 0 0.15 Current 100, Voltage 120 2 2.3 7 3.3 One 1.2 0.5 2.8 0.9 1.9 0.8 0.5 2 0.5 3.2 2.25 0.25

From the measurement results of Table 1a and Table 1b, the vibration is most severe in the low frequency band near the third harmonic of 360 [Hz] in the conventional transformer, and in the high frequency band, it is not as large as near 360 [Hz] but in the middle. It can be seen that the vibration of various frequencies are generated by the size of.

As described above, the conventional transformer generates noise due to a combination of extreme vibrations in the low frequency band near 360 [Hz] and vibrations occurring in various high frequency bands.

7A and 7B show visually well the extreme vibrations occurring in the low frequency band near the 360 [Hz] band and the vibrations occurring in the various high frequency bands in the conventional transformer.

Subsequently, Tables 2a and 2b below show numerical values of vibration frequencies transmitted from the assembly 7 to the enclosure 1 in the noise reduction transformer of the present invention provided with the first support and vibration damping means 13. It is described.

Here, Table 2a shows the vibration frequency when the insulating oil is at room temperature and Table 2b shows the reference when the insulating oil is saturated.

8A and 8B are graphs based on the numerical values of Tables 2A and 2B.

120 240 360 480 600 720 840 980 1080 1200 1320 1460 1580 1700 1820 1960 2080 Current 50, Voltage 90 1.9 0.2 0.72 0.42 0.05 0.1 0 0.1 0.32 0.14 0.14 0.6 0.25 0 0.1 0 0 Current 50, Voltage 100 2.4 0.2 1.7 0.7 0 0.3 0 0.2 0.5 0.2 0.5 0.8 0.1 0 0 0.1 0.1 Current 50, Voltage 110 2.8 0.3 2.6 0.5 0.3 0.5 0 0.3 0.5 0.3 0.8 2 1.55 0.1 0.1 0.1 0.1 Current 50, Voltage 120 2.3 3.1 2.75 3.25 One 1.2 1.3 0.6 0.4 0.45 0.3 0.4 0.3 0 0.3 0.1 0.15 Current 50, Voltage 90 1.4 1.15 0.8 0.45 0.1 0.1 0.2 0.1 0.3 0.35 0.45 0.4 0.1 0 0.1 0.1 0.1 Current 100, Voltage 100 1.5 2.1 1.4 0.52 0.4 0.5 0.1 0.1 0.25 0.1 0.3 0.35 0.35 0.1 0.1 0.1 0.1 Current 100, Voltage 110 1.45 2.85 2 0.8 0.7 0.75 0.1 0.2 0.3 0.2 0.3 0.8 0.7 0 0.15 0 0 Current 100, Voltage 120 1.7 3.2 2.55 3.3 0.7 1.3 0.4 0.5 0.45 0.5 0.3 0.6 0.35 0 0.4 0.1 0

120 240 360 480 600 720 840 980 1080 1200 1320 1460 1580 1700 1820 1960 2080 Current 50, Voltage 90 0.88 1.06 0.82 0.28 0.34 0.1 0 0.1 0.27 0.52 0 0.32 0.73 0 0.1 0 0 Current 50, Voltage 100 One 1.25 2 0.3 0.3 0.3 0 0 0.3 1.2 0.1 0.55 1.7 0.1 0 0 0 Current 50, Voltage 110 0.75 1.3 2.4 1.2 1.2 0.9 0.2 0.2 0.5 0.8 0.3 1.2 5.1 0.2 0 0.2 0 Current 50, Voltage 120 1.7 1.4 4.6 3.75 3.75 1.15 0.6 0.8 One 0.2 0.75 4.75 0.4 0.85 0.65 0 0.4 Current 50, Voltage 90 2.7 0.7 0.5 0.2 0.2 0.15 0.2 0.1 0.1 0.3 0.7 0.35 One 0 0 0 0 Current 100, Voltage 100 2.05 One 1.85 0.2 0.2 0.3 0.1 0.1 0.75 0.1 0.1 0 0 0 0 0 0 Current 100, Voltage 110 1.3 1.1 2.1 0.9 0.9 0.7 0.2 0 0.5 0.75 0.3 1.3 6.85 0.2 0 0 0 Current 100, Voltage 120 1.5 One 3.5 3.15 3.15 0.8 0.7 0.7 0.5 1.1 0.2 One 8.5 0.8 0.7 1.1 0

As is clearly seen from the measurement results of Tables 2a and 2b, in the noise reduction transformer of the present invention provided with the first support and vibration damping means 13, vibrations in the high frequency region and the low frequency region are higher than those of the conventional transformer. Markedly attenuated.

In particular, in the low frequency band near 360 [Hz] where vibration was the most severe, the magnitude of the amplitude was reduced to about 3 [dB] compared with the conventional, which is a level that can recognize and feel the degree of noise reduction. Corresponds to

In addition, it can be seen that the present invention has an effect of reducing noise when the amplitude of the vibration frequency, which has conventionally appeared in various high frequency bands, is also reduced.

Thus, in the present invention, the low-frequency band up to 500 [Hz] acts to attenuate the vibration by acting the plate spring 23, NBR packing (21) in the band of 500 [Hz] or more, especially around 1000 [Hz] ) Has the effect of reducing noise by reducing vibration.

Subsequently, Tables 3a and 3b below describe numerical values of vibration frequencies transmitted from the assembly 7 to the enclosure 1 in the noise reduction transformer of the present invention, where the first support and vibration damping are described. Considering the case where the second support and vibration damping means 29 are simultaneously installed together with the means 13.

However, Table 3a shows the vibration frequency when the insulating oil is at room temperature and Table 3b is when the insulating oil is saturated.

9A and 9B are graphs based on the numerical values of Tables 3A and 3B.

120 240 360 480 600 720 840 980 1080 1200 1320 1460 1580 1700 1820 1960 2080 Current 50, Voltage 90 2.3 0.3 0.2 0.3 0.1 0.05 0 0.1 0.4 0.55 0.2 0.1 0.2 0 0 0 0 Current 50, Voltage 100 2.7 0.5 0.5 0.5 0.3 0.4 0.1 0.2 0.75 0.85 0.3 0.1 0.25 0 0.1 0.05 0 Current 50, Voltage 110 3.15 0.75 0.55 0.25 One 0.75 0.2 0.4 0.4 0.8 0.6 0.25 0.45 0.1 0.1 0 0 Current 50, Voltage 120 4 0.65 One 1.62 0.9 1.55 1.6 0.7 0.2 0.3 0.45 0.35 0.1 0.15 0.1 0 0 Current 50, Voltage 90 2.25 0.2 0.45 0.45 0.1 0.1 0.1 0.2 0.45 0.6 0.3 0.1 0.3 0 0 0 0 Current 100, Voltage 100 2.5 0.3 0.55 0.4 0.3 0.45 0 0.3 0.7 0.8 0.35 0.1 0.2 0 0 0 0 Current 100, Voltage 110 2.9 0.65 0.7 0.3 1.05 0.7 0.2 0.3 0.55 0.9 0.45 0.2 0.4 0.1 0.1 0.1 0 Current 100, Voltage 120 4.25 0.85 1.3 1.5 0.4 1.9 1.3 1.2 0.7 0.75 0.6 0.4 0.45 0.45 0.5 0.45 0

120 240 360 480 600 720 840 980 1080 1200 1320 1460 1580 1700 1820 1960 2080 Current 50, Voltage 90 2.4 0.15 0.35 0.25 0.1 0.15 0.1 0.1 0.5 0.51 0.2 0.25 0.35 0.2 0.2 0.1 0.1 Current 50, Voltage 100 2.8 0.1 0.9 0.4 0.3 0.3 0.3 0.5 0.45 0.5 0.4 0.4 0.45 0.25 0.1 0.1 0.1 Current 50, Voltage 110 3.4 0.3 1.25 0.3 0.9 0.1 0.4 0.6 0.3 0.65 0.3 0.65 0.55 0.15 0.15 0.1 0.15 Current 50, Voltage 120 5.2 0.45 One 5.8 0.3 0.32 One 2.5 0.95 One 0.5 0.8 0.9 0.9 0.55 0.5 0.8 Current 50, Voltage 90 1.72 0.23 0.36 0.2 0.23 0.1 0.1 0.1 0.4 0.46 0.22 0.22 0.25 0.33 0.1 0.1 0..1 Current 100, Voltage 100 2.35 0.35 0.7 0.25 0.3 0.4 0.2 0.3 0.6 0.7 0.25 0.4 0.35 0.15 0.15 0.1 0.1 Current 100, Voltage 110 2.9 0.7 0.75 0.3 One 0.3 0.3 0.6 0.2 0.6 0.2 0.6 0.2 0.35 0.4 0.1 0.1 Current 100, Voltage 120 4.95 0.7 1.2 5.1 0.3 0.3 0.7 1.5 1.2 1.4 0.2 0.9 1.6 1.05 0.7 0.7 0.7

As can be seen from the measurement results in 3a and 3b, in the noise reduction transformer of the present invention in which the second support and vibration damping means 29 are simultaneously installed together with the first support and vibration damping means 13, a conventional transformer is known. In comparison with this, vibrations in the high frequency region and the low frequency region are significantly attenuated.

In particular, it can be seen that the vibration of the thirteenth harmonic band is significantly attenuated in the eighth harmonic band, which is sensitive to noise, instead of increasing about 1.5 times the vibration of the fundamental frequency 120 [Hz] compared to the conventional transformer.

Here, when the second support and vibration damping means 29 are installed together with the first support and vibration damping means 13, the first support and vibration damping means 13 are almost as compared to the case where only the first support and vibration damping means 13 are installed alone. Although similar effects are achieved, it can be seen that the vibrations in the high frequency band of the conventional transformer are more stably attenuated.

The operation of the noise reduction transformer according to the present invention configured as described above will be described in detail with reference to the accompanying drawings.

First, when a voltage is applied to the transformer of the present invention and current flows through the winding 5, the assembly 7 composed of the winding 5 and the iron core 3 vibrates while the iron core 3 is magnetically distorted.

At this time, the vibration generated in the assembly 7 is slightly attenuated by the upper frame 9 and the lower frame 11 which tighten the iron core 3.

This slightly attenuated vibration is transmitted to the support bolt 17 through a connecting piece 19 coupled to the upper frame 9. However, the vibration is attenuated by the NBR packing 21 in close contact with both sides of the connecting piece 19 in this process.

In particular, the vibration of the high frequency region is significantly attenuated by the NBR packing 21.

Thereafter, the vibration that is not extinguished is transmitted to the enclosure 1, and in this process, the vibration is attenuated a lot by the dish spring 23 installed between the enclosure 1 and the NBR packing 21.

In particular, vibration of the low frequency region is significantly attenuated by the dish spring 23.

Thus, the vibration generated in the assembly 7 is transmitted to the enclosure 1 in attenuated state in both the low frequency region and the high frequency region, and thus, the attenuation of the vibration transmitted from the assembly 7 to the enclosure 1. The occurrence of noise is suppressed.

In addition, when the NBR packing or the cork packing, which is the second support and vibration damping means 29, is inserted into the bottom of the assembly 7 and the enclosure 1, the vibration of the high frequency region is more stably attenuated.

The preferred embodiment of the present invention has been described above. The present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

As described above, the noise reduction transformer according to the present invention has an effect of effectively attenuating both high frequency and low frequency band vibrations transmitted from the assembly to the transformer enclosure without complex vibration damping devices, thereby suppressing noise generation.

In addition, the present invention has the effect of preventing the problem that the noise deteriorates as the mechanical vibration between the enclosure and the assembly is loosened over time.

1 is a cross-sectional view for explaining the configuration of a conventional distribution transformer.

2 is a cross-sectional view for explaining the configuration of the noise reduction transformer of the present invention.

Fig. 3 is a reference view showing A of Fig. 2 to explain the configuration of the first supporting and vibration damping means.

Figure 4 is an exploded perspective view of the first support means and vibration damping means of the present invention.

5 is a side cross-sectional view showing a form in which a plurality of dish springs are superimposed in series.

6 is a cross-sectional view of the present invention in which the second support and vibration damping means are adopted.

Figure 7a is a graph measuring and displaying the vibration of the conventional transformer for each frequency band when the insulating oil is room temperature.

Figure 7b is a graph showing the measurement of the vibration of the conventional transformer for each frequency band when the insulating oil is saturated temperature.

Figure 8a is a graph showing the measurement by the frequency band of the vibration of the present invention provided with the first support and vibration damping means when the insulating oil at room temperature.

8B is a graph showing the measurement and display of the vibration of the present invention for each frequency band in which the first supporting and vibration damping means are installed when the insulating oil is at a saturation temperature.

Figure 9a is a graph showing the measurement by measuring the frequency band vibration of the present invention provided with the first support and vibration damping means and the second support and vibration damping means when the insulating oil at room temperature.

9B is a graph showing the measurement of the vibration of the present invention in which the first support and vibration damping means and the second support and vibration damping means are measured for each frequency band when the insulating oil is at a saturation temperature.

* Description of the symbols for the main parts of the drawings *

1: enclosure 3: iron core

5 winding 7 assembly

9: upper frame 11: lower frame

13: first support and vibration damping means 19: connecting piece

21: NBR Packing 23: Dish Spring

29: second support and vibration damping means

Claims (4)

Enclosure; An assembly installed in the enclosure and composed of an iron core and a winding; An upper frame coupled to an upper end of the iron core to tighten an upper portion of the iron core; A lower frame coupled to the bottom of the iron core to tighten the lower portion of the iron core; And a first support and vibration damping means installed between each of the inner side walls of the enclosure and the upper frame to support the assembly to the enclosure and to attenuate vibration transmitted from the assembly to the enclosure. Noise reduction transformer. The method of claim 1, wherein the first support and vibration damping means, A fixing nut fixed to the inner wall of the enclosure; A support bolt fastened horizontally to the fixing nut; A connecting piece coupled to the upper frame and inserted into the support bolt to support the assembly to the support bolt; NBR packing is fitted to the support bolt, respectively installed on both sides of the connecting piece; A spring fitted to the support bolt and installed between the fixing nut and the NBR packing;  And a tightening nut fastened to the support bolt to tighten the connecting piece, the NBR packing, and the spring toward the fixing nut. The method of claim 2, Noise reduction transformer, characterized in that the spring is a dish spring. The method of claim 1, It is installed between the bottom of the enclosure and the lower frame, the second support and vibration damping means for attenuating the vibration transmitted from the assembly to the bottom of the enclosure while supporting the assembly that any one of cork packing or NBR packing is further included. Noise reduction transformer characterized by the above-mentioned.