JP5580688B2 - Ground-mounted transformer device - Google Patents

Description

  The present invention relates to a ground-mounted transformer device installed on a sidewalk or the like.

  A ground-mounted transformer device is provided to convert a high voltage drawn from a high-voltage distribution line buried underground into a low voltage to be supplied to consumers. As shown in Patent Document 1 It is composed of an outer box made of steel plate and the like, and a transformer housed in the outer box together with protective devices such as a switch, and is installed on the side of the sidewalk near the roadway.

  In a ground-mounted transformer device, in order to prevent the winding temperature of the transformer from rising and prematurely deteriorating, a ventilation port with a louver attached to the side wall of the outer box is provided to generate heat generated from the transformer. By releasing the air in the outer box heated by the outside from the ventilation port, the temperature rise of the transformer is suppressed.

JP 2010-104192 A

  The transformer generates noise due to the vibration of the coil caused by the electromagnetic force acting on the coil conductor and the vibration of the iron core caused by the magnetic force acting on the steel plate constituting the iron core. Noise generated by the vibration of the iron core and coil conductor leaks outside through the insulating oil of the transformer, the transformer tank, and the outer box. If a large noise is generated from a ground-mounted transformer device, there is a risk of giving a sense of incongruity to passers-by, or causing discomfort to neighboring residents in the time zone such as midnight when the road is quiet. Therefore, in order to achieve harmony with the surrounding environment, it is preferable to reduce the noise leaking from the ground-mounted transformer device as much as possible.

  As a soundproofing measure for the ground-mounted transformer device, it is conceivable to attach a sound absorbing material or a sound insulating material to the inner surface of the outer box. However, a method of attaching a sound absorbing material or a sound insulating material to the inner surface of the outer box is not allowed because it prevents heat dissipation from the outer box and causes a rise in the temperature of the transformer.

  An object of the present invention is to provide a ground-mounted transformer capable of reducing noise leaking from the outer box to the outside without particularly complicating the structure inside the outer box or causing an increase in the temperature of the transformer. It is to provide a device.

  The present invention is directed to a ground-mounted transformer device including a rectangular parallelepiped outer box and a transformer accommodated in the outer box. In the transformer device to which the present invention is directed, the transformer is accommodated in a rectangular parallelepiped transformer tank arranged with four side walls facing the four side walls of the outer box, respectively, and the transformer tank. A ventilation opening to which a louver is attached is provided on two side walls of the outer box that respectively face two adjacent side walls of the transformer tank. Between the two side walls of the transformer tank and the two side walls of the outer box, a space having an L shape is formed when viewed from above, and partition walls respectively disposed at both ends of the L shape space, The L-shaped space and the other space in the outer box are partitioned.

  In the present invention, a partition plate extending vertically between the transformer tank and the outer box is disposed at the corner portion of the L-shaped space, and the L-shaped space is formed by the partition plate into the transformer tank. The two side walls are partitioned into two spaces, a space facing one side and a space facing the other side wall.

  The partition plate extends along one corner of the transformer tank that forms a boundary between the two side walls of the transformer tank and one corner of the outer box that faces the one corner of the transformer tank. It is preferable to be provided so as to extend vertically.

  As described above, a partition plate extending vertically between the transformer tank and the outer box is arranged at the corner portion of the L-shaped space formed between the transformer tank and the outer box. When the partition plate divides the L-shaped space into two spaces, one facing one of the two side walls of the transformer tank and the other facing the other, it becomes clear that the noise reduction effect is remarkably obtained. It was.

  According to the present invention, it is possible to reduce noise leaking from the outer box only by installing the partition plate at the corner portion of the L-shaped space formed between the transformer tank and the outer box. Thus, a low-noise ground-mounted transformer device can be obtained without complicating the structure and without causing an increase in the temperature of the transformer.

It is a front view which shows an example of the external appearance of the ground installation type transformer apparatus concerning this invention. FIG. 2 is a left side view of the ground-mounted transformer device shown in FIG. 1. It is sectional drawing along the III-III line of FIG. FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. It is the table | surface which showed the experimental result of the noise measurement performed about one Example of the ground installation type transformer apparatus concerning this invention.

  1 to 4, 1 is a rectangular parallelepiped outer box, and 2 is a transformer accommodated in the outer box 1. The outer box 1 includes a rectangular bottom plate 100, first to fourth side walls 101 to 104 erected vertically from four sides of the bottom plate 100, and an opening portion above a space surrounded by the side walls 101 to 104. And a ceiling plate 105 to be closed.

  The transformer 2 is a rectangular parallelepiped transformer tank 2A having a rectangular bottom plate 200, first to fourth side walls 201 to 204 erected vertically from four sides of the bottom plate 200, and a ceiling plate 205, a transformer It consists of the transformer main body 2B accommodated with the insulating oil in the tank 2A. The transformer 2 fixes the bottom plate 200 of the transformer tank 2A to the bottom plate 100 of the outer box via the installation base 20, and the first to fourth side walls 201 to 204 of the transformer tank are respectively connected to the first box of the outer box 1. Or it is accommodated in the outer box 1 in a state of being opposed to the fourth side walls 101 to 104.

  A first radiator 211 and a second radiator 212 are attached to the adjacent first and second side walls 201 and 202 of the transformer tank 2A, respectively. The first radiator 211 attached to the wide first side wall 201 includes two radiator units 211A and 211B arranged in the lateral direction, and the second side wall is narrower than the first side wall 201. The second radiator 212 attached to 202 is constituted by a single radiator unit. Although not shown in detail in the drawing, as the radiator units constituting the first and second radiators 211 and 212, a number of hollow radiator panels having oil passages inside are arranged at intervals. Arrange the oil passages in the series of heat dissipating panels to communicate with the transformer tank, or fold the steel plate into a corrugated shape so that peaks and troughs appear alternately. Corrugated heat sinks are used in which the hems at both ends are welded to form oil passages inside each peak. The first and second radiators 211 and 212 cool the insulating oil by receiving the insulating oil in the transformer tank therein and performing heat exchange with the air in the outer box.

  Rectangular vents 221 and 222 are provided at the upper and lower portions of the first side wall 101 of the outer box 1, and louvers 223 and 224 are attached so as to close these vents. In addition, a rectangular ventilation port 225 is provided on the upper portion of the second side wall 202 of the outer box 1, and a louver 226 is attached so as to close the ventilation port. The gallery is a panel having a structure in which a large number of blind wings are arranged to form a gap between the wings, and is used for blinding while ensuring a ventilation function.

  A three-phase low-pressure bushing 230 is attached through the upper part of the side wall 203 of the transformer tank 2. The end located in the transformer tank of the central conductor of the low-voltage bushing 230 is connected to the secondary side of the transformer body 2B. Outside the third side wall 203 of the transformer tank, wiring breakers 3 for a plurality of lines (three lines in the illustrated example) are attached below the low pressure bushing 230. The low-voltage bushing 230 and the input-side terminal of the circuit breaker of each line are connected via a connection conductor (not shown), and the three-phase low-voltage of each line is connected to the output-side terminal of the circuit breaker 3 for each line. Cable 4 is connected. The low-voltage cable 4 of each line is connected to a distribution line connected to the customer through the underground cable pit.

  A three-phase high-voltage bushing 231 is attached through the fourth side wall 204 of the transformer tank 2, and one end disposed in the transformer tank of the central conductor of these high-voltage bushings is the primary side of the transformer body 2B. It is connected to the. The other end of the high-pressure bushing 231 is connected to a terminal portion of the high-voltage cable 5 raised from the underground via the primary side switch 6. The primary-side switch 6 has a fixed contact and a movable contact, and includes a switch body that opens and closes between the high-voltage cable 5 and the primary side of the transformer body 2B, and a case 601 that houses the switch body. And is supported by the fourth side wall 204 of the transformer tank 2A.

  In a ground-mounted transformer device, a means for interrupting an accident current is provided on the primary side of the transformer. As means for interrupting the fault current, a high-voltage current limiting fuse or a circuit breaker is used. The high-voltage current limiting fuse is built in the movable contact of the primary side switch 6 or is provided separately from the primary side switch, and is inserted between the high voltage cable 5 and the primary side of the transformer body 2B. The In the illustrated example, it is assumed that a high-voltage fuse is built in the movable contact of the primary side switch.

  A partition wall 7 extending between the end of the second side wall 202 of the transformer tank 2A near the third side wall 203 and the second side wall 102 of the outer box 1 to partition the low pressure side and the high pressure side; The partition wall 8 extending between the end of the third side wall 203 of the transformer tank 2A on the fourth side wall 204 side and the third side wall 103 of the outer box 1, and the fourth side wall 204 of the transformer tank 3, the partition wall 9 extending between the end portion near the side wall 203 and the fourth side wall 104 of the outer box, the end portion near the fourth side wall 204 of the first side wall 201 of the transformer tank 2A, and the outer box A partition wall 10 extending between the first side wall 101 and the first side wall 101 is provided.

  In order to enable maintenance and inspection of the secondary-side protective equipment including the circuit breaker 3 for wiring, a door is provided on the third side wall 103 of the outer box 1 and the primary side protection including the primary-side switch 6 is provided. In order to enable maintenance and inspection of the equipment, doors are provided on the fourth side wall 104 of the outer box 1, but these doors are not shown.

  In the ground-mounted transformer device of the present embodiment, it is necessary to attach a high-voltage bushing 231 and a primary-side protective device including the primary-side switch 6 to the fourth side wall 204 of the transformer tank 2A. The secondary side protection device including the low pressure bushing 230 and the circuit breaker 3 for wiring needs to be attached to the third side wall 203 of the container tank 2A. Therefore, a radiator cannot be attached to the third side wall 203 and the fourth side wall 204 of the transformer tank 2A. The first and second radiators 211 and 212 need to be attached to the other two side walls 201 and 202 of the transformer tank 2A. Therefore, in this type of ground-mounted transformer device, the first and second side walls 201 and 202 of the transformer tank to which the first and second radiators 211 and 212 are respectively attached, and the side walls 201 A space 11 having an L shape when viewed from above is formed between the first and second side walls 101 and 102 of the outer box 1 facing each other. Both ends of the L-shaped space 11 are partitioned from other spaces by partition walls 7 and 10 extending vertically between the transformer tank and the outer box.

  In order to efficiently cool the transformer, it is necessary to suppress a temperature rise in the L-shaped space 11 in which the radiators 211 and 212 are arranged. Therefore, in this type of ground-mounted transformer device, the first side wall of the outer box facing the L-shaped space 11 is used to release the hot air in the L-shaped space where the radiators 211 and 212 are disposed to the outside. Ventilation ports 221 and 222 having louvers 223 and 224 attached thereto are provided on 101, and vent holes 225 having louvers 226 attached are also provided on the second side wall 102 facing the L-shaped space 11.

  In the ground-mounted transformer device to which the present invention is directed, the sound wave of noise radiated from the transformer to the surroundings and the sound wave of noise reflected from each part of the outer box after being radiated from the transformer are external. If they interfere with each other in the box, the level of noise rises and the level of noise leaking from the outer box to the outside increases. In particular, at the corner of the L-shaped space formed between the transformer tank and the outer box, noise radiated from the transformer and noise reflected from each part of the outer box after radiated from the transformer Since it is easy to gather, interference of noise occurs actively, and the increase of the noise level generated in this portion is considered to be a major cause of increasing the noise level of the entire apparatus. Further, when a specific frequency component of the noise resonates in the outer box, the frequency component is increased, and thus noise leaking from the outer box to the surroundings increases. Therefore, in order to reduce the level of noise leaking from the ground-mounted transformer device, the interference of noise occurring at the corner portion of the L-shaped space formed between the transformer tank and the outer box is reduced. It is also effective to suppress resonance of noise generated in the outer box.

  In the present invention, based on the above examination results, a partition plate extending up and down is disposed across the transformer tank and the outer box at the corner portion of the L-shaped space. The L-shaped space is divided into a first space where one of the two side walls 201 and 202 of the transformer tank faces and a second space where the other 202 faces. In the example shown in the drawing, a rectangular plate having a vertically long shape is used as the partition plate 12, and one end of the width direction forms one corner that forms a boundary between the first and second side walls 201 and 202 of the transformer tank 2A. Along the portion 2a, the other end in the width direction is arranged along one corner 1a of the outer box facing one corner 2a of the transformer tank. Further, the height of the partition plate 12 is set so that the lower end of the partition plate is brought into contact with the bottom plate of the outer box and the upper end thereof is brought into contact with the ceiling plate 105 of the outer box. The partition plate 12 can be formed of a metal plate having a sound insulating property such as a steel plate, a plate made of a material having a sound absorbing property, or a composite plate in which a plate of a material having a sound absorbing property is attached to a metal plate.

  As described above, when the partition plate 12 extending vertically is arranged in the corner portion of the L-shaped space 11 across the transformer tank 2A and the outer box 1, the noise leaking from the outer box to the surroundings is reduced. It was confirmed by experiment that the effect to do was acquired notably.

  In the experiment, the ground-mounted transformer device having the configuration of the above embodiment was installed in a quiet environment in the factory, and a rated voltage of 50 Hz was applied to the primary side of the transformer, as shown in FIG. Noise was measured at eight measurement points of I, J, K, L, M, N, O, and P. At each measurement point, as shown in FIG. 4, the distance d1 measured in the horizontal direction from the outer box is 30 [cm], and the distance d2 measured in the vertical direction from the installation surface of the ground-type transformer device is 150 [cm]. The sound level meter 30 was set at the position of cm]. The noise was measured for each of a state before installing the partition plate 12 in the corner portion of the L-shaped space and a state after installing the partition plate 12. The measurement results of noise are shown in FIG. The unit of measured values in the table of FIG. 5 is [dB].

  As is clear from FIG. 5, when the partition plate is provided at the corner portion of the L-shaped space, the maximum is 6.9 [dB], the minimum is 0.9 [dB], and the minimum is 3.0 [dB] than the case where the partition plate is not provided. [dB] or more (average 3.5 [dB]) The noise level was reduced, and it was confirmed that the noise level was reduced at all measurement points set around the outer box.

  As described above, when the partition plate is provided at the corner portion of the L-shaped space 11 formed inside the ventilation opening of the outer box, the interference of noise occurring at the corner portion of the L-shaped space 11 is suppressed, and the sound wave The increase in the noise level caused by the interference can be suppressed, and by dividing the L-shaped space with the partition plate, the acoustic characteristics in the outer box can be changed to suppress noise resonance, etc. It seems that the level of noise leaking to the surroundings can be reduced.

  As in the above embodiment, one corner 2a of the transformer tank that forms a boundary between the two side walls of the transformer tank and one corner of the outer box that faces the one corner 2a of the transformer tank. If the partition plate is provided along the portion 1a (stretching the corner of the transformer tank and the corner of the outer box), positioning of the partition plate can be facilitated. However, the partition plate may be provided so as to partition the two radiators at the corner portion of the L-shaped space, and is not necessarily provided across the corner portion of the transformer tank and the corner portion of the outer box. For example, in FIG. 3, a partition plate may be provided between a position slightly closer to the radiator 212 than the corner 1a of the side wall 102 of the outer box and the corner 2a of the transformer tank 2A.

  In the above embodiment, the height of the partition plate is set so that the upper end of the partition plate 12 reaches the ceiling plate of the outer box. However, the partition plate 12 interferes with noise near the corner portion of the L-shaped space 11. It suffices to have a height sufficient to prevent the occurrence of the occurrence, and it is not always necessary to have a height that reaches the ceiling plate of the outer box.

  As described above, the present invention has a simple configuration in which the partition plate is arranged at the corner portion of the L-shaped space in the outer box in which the radiator of the transformer is arranged, and the noise leaking from the ground-mounted transformer device can be reduced. It can be reduced and the ground-mounted transformer device can be reduced in noise without causing a significant increase in cost, and can be harmonized with the surrounding environment, so the industrial applicability is great. It is.

DESCRIPTION OF SYMBOLS 1 Outer box 100 Outer box bottom plate 101-104 Outer box side wall 105 Outer box ceiling board 1a One corner of outer box 2 Transformer 2A Transformer tank 200 Transformer tank bottom plate 201-204 Side wall of transformer tank 205 ceiling plate of transformer tank 211, 212 radiator 230 low pressure bushing 231 high voltage bushing 2B transformer main body 2a one corner of transformer tank 3 distribution circuit breaker 4 low voltage cable 5 high voltage cable 6 primary side switch 7-10 Partition 12 Partition plate

Claims (1)

A rectangular parallelepiped outer box and a transformer housed in the outer box, the transformer having a rectangular parallelepiped shape arranged with four side walls facing the four side walls of the outer box, respectively. Ventilation having a transformer tank and a transformer main body accommodated in the transformer tank, and having galleys attached to two side walls of the outer box respectively facing two adjacent side walls of the transformer tank. A space is formed between the two side walls of the transformer tank and the two side walls of the outer box, and an L-shaped space is formed between the two side walls of the transformer tank. In the ground-mounted transformer device in which the L-shaped space and the other space in the outer box are partitioned by the partition walls arranged,
In the corner portion of the L-shaped space, a partition plate extending vertically is disposed across the transformer tank and the outer box,
The partition plate includes one corner of the transformer tank that forms a boundary between the two side walls of the transformer tank and one corner of the outer box that faces one corner of the transformer tank. And the partition plate divides the L-shaped space into a space facing one of the two side walls of the transformer tank and a space facing the other. A ground-mounted transformer device, characterized in that

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