JP2016213912A - Metal component and electrical equipment using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a metal component capable of preventing temperature rising within a switchboard by arranging open slits in a partition plate of the switchboard as an electrical equipment.SOLUTION: In a metal plate constituting a grounding metal cover 1 as a metal component, plural cross holes 8a as through holes are disposed in matrix, and in an area A enclosed by cross holes 8a of two rows and two columns, a cross hole 8b as a through hole is dispose being tilted. By forming plural cross holes 8a and 8b as openings in a staggered arrangement in a grounding metal cover 1, a complicated labyrinthine structure is obtained and eddy current, which is generated by the operation of the switchboard, flows taking a roundabout route.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a metal part arranged around a conductive part through which a current flows, and an electric device using the metal part.

  For example, there is a high-voltage charging unit inside heavy electrical equipment such as a switchboard, and this high-voltage charging unit is covered with a grounded metal. The switchboard is divided into a circuit breaker room that houses the circuit breaker, a bus room that houses the main bus, and a cable room that houses the secondary conductor of the circuit breaker and the external cable. Each section is partitioned by a partition plate made of ground metal. It has been. Here, when the insulation distance from the conductive portion is insufficient, each section may be partitioned using an insulator instead of a ground metal.

  When the switchboard is operated, the conductive part in the panel generates heat due to energization, and the temperature in the panel located around the conductive part increases accordingly. However, the regulation stipulates that the temperature inside the panel must be kept below a certain value. Therefore, by providing slits on the door surface and ceiling surface of the switchboard and further providing slits in the partition plate in the panel described above, measures are taken to create a flow of air in the panel and suppress temperature rise during energization operation. Sometimes. However, when the operating current value is large, the temperature rise may not be suppressed so that the specified value is obtained even if the above measures are implemented.

  Another factor causing the temperature rise in the panel is temperature rise due to eddy current. By supplying a current to the conductive part, a magnetic field is generated around the conductive part, and an eddy current is generated in the ground metal installed near the conductive part. Due to this eddy current, the temperature of the ground metal rises. These have a greater effect as the energization current value increases. As a countermeasure, there is a method in which the ground metal in the vicinity of the conductive portion is made of a nonmagnetic metal such as stainless steel so that it is not easily affected by eddy currents caused by a magnetic field.

In addition, an example is shown in which a hardened hard part is partially formed on the ground metal side to make it non-magnetic, thereby increasing the magnetic resistance and suppressing the generation of eddy currents (see, for example, Patent Document 1).
Furthermore, an example in which a linear slit is provided in the contact in order to suppress eddy current is shown (for example, see Patent Document 2 and FIG. 9).

Japanese Patent Publication No. 5-52121 JP 2011-142035 A

In order to suppress temperature rise during operation of electrical equipment such as switchboards, the partition plate placed in the panel is changed from a steel plate to a non-magnetic metal such as stainless steel, or partially with respect to the partition plate. There is a technique for providing a hardened hard part, but these methods have a problem that the cost is increased due to the process of changing the material and providing the hardened hard part.
In addition, in the conventional partition plate, it is necessary to form the hardened hard part or the slit extending direction intersecting depending on the direction in which the eddy current is generated. In the case where the directions in which the currents extend are parallel, the energization path of the eddy current cannot be lengthened, so that the resistance cannot be increased and the effect of suppressing the temperature rise cannot be obtained.

  The present invention has been made to solve the above-described problems, and provides a metal component capable of suppressing a temperature rise without depending on the direction of eddy current generated in an electric device. It is.

A metal part according to the present invention is a metal part that divides the interior of an electric device into a plurality of sections and surrounds a conductive portion arranged in each section, and penetrates the metal plate with respect to the metal plate constituting the metal part. A plurality of eddy current bypass holes are formed, and the eddy current bypass holes are aperture-shaped holes that are a combination of a plurality of linear holes that obstruct the path of eddy current generated in the metal part. Part.
In addition, an electrical apparatus according to the present invention is characterized in that the above-described metal component is used in a partition plate that divides the inside of the apparatus into sections or a portion where an eddy current is generated by an alternating current.

According to the metal part of the present invention, by forming a plurality of eddy current bypass holes in the metal plate, the metal part has a labyrinth structure that bypasses the hole part, and the eddy current path generated by the operation of the electrical equipment is complicated. It can be made. As a result, the energization path of the eddy current generated in the metal part is longer than when energizing in the linear direction, and the resistance can be increased. Therefore, the eddy current can be suppressed, and the temperature rise in the electrical equipment can be suppressed. Is possible.
Further, according to the electric device of the present invention, by using the above-described metal component, it is possible to suppress eddy current generated by the operation of the electric device, and it is possible to suppress a temperature rise in the electric device.

It is a top view of the ground metal cover in Embodiment 1 of this invention. It is a block diagram of the switchboard which provided the partition by the ground metal cover in Embodiment 1 of this invention. It is the figure which showed the example of arrangement | positioning of the cross-shaped hole opened to the earthing | grounding metal cover in Embodiment 1 of this invention. It is explanatory drawing which shows that an eddy current generate | occur | produces in a ground metal cover. It is explanatory drawing which shows that an eddy current flows into the ground metal cover in Embodiment 1 of this invention. It is a figure which shows the modification of the cross-shaped hole opened to the earthing | grounding metal cover in Embodiment 2 of this invention, and the example of arrangement | positioning. It is the figure which showed the example of arrangement | positioning of the cross-shaped hole opened to the earthing | grounding metal cover in Embodiment 3 of this invention, and a hole part. It is the figure which showed the example of arrangement | positioning of the H-shaped hole opened to the earthing | grounding metal cover in Embodiment 4 of this invention. It is the figure which showed the example of arrangement | positioning of the W-shaped hole opened to the earthing | grounding metal cover in Embodiment 5 of this invention. It is the figure which showed the example of arrangement | positioning of the V-shaped hole opened to the earthing | grounding metal cover in Embodiment 6 of this invention.

Embodiment 1 FIG.
Hereinafter, a ground metal cover (corresponding to a metal part) according to Embodiment 1 of the present invention will be described with reference to FIGS.
FIG. 1 illustrates a plan view of a ground metal cover 1 according to Embodiment 1 of the present invention. The ground metal cover 1 is made of a metal plate, and slits 8 penetrating the metal plate are formed in a predetermined arrangement pattern on the surface of the ground metal cover 1 as shown in a partially enlarged view. The arrangement pattern of the slits 8 will be described later.
FIG. 2 is a configuration diagram of a switchboard 100 (corresponding to an electric device) using the ground metal cover 1 as a partition plate. As illustrated in FIG. 2, inside the switchboard 100, a busbar chamber 3 for storing the busbar 2, a circuit breaker chamber 5 for storing the circuit breaker 4, and an external cable 6 extending from the load side of the circuit breaker 4 to the outside are stored. A cable chamber 7 is provided, and a ground metal cover 1 made of a metal plate is used as a partition plate used to separate the chambers (sections). In FIG. 2, the ground metal cover 1 is used as a partition plate that divides the bus room 3 and the cable room 7.
The ground metal cover 1 can also be used as an external casing of the switchboard 100 in addition to the partition plate that divides the internal space of the switchboard 100. The conductive portion is disposed around the conductive portion that becomes the high-voltage charging unit. It is arranged and used so as to surround it.

  Next, the slit 8 opened in the ground metal cover 1 shown in FIG. 1 will be described in detail. FIG. 3 shows a cross-shaped hole 8a (in the first eddy current bypass hole) which is a slit 8 (corresponding to an eddy current bypass hole) opened in the ground metal cover 1 according to the first embodiment of the present invention. And a cross-shaped hole 8b (corresponding to a second eddy current bypass hole). The cross-shaped holes 8a and 8b are through-holes formed in the metal plate constituting the ground metal cover 1, and the cross-shaped holes 8a are arranged in rows and columns in the vertical and horizontal directions on the surface of the metal plate. Patterning is performed so that the cross-shaped hole 8b is positioned at the center in the region A surrounded by the four rows of four cross-shaped holes 8a.

The cruciform hole 8b arranged in the area A in the opening pattern is arranged by being rotated 45 degrees with respect to the arrangement of the cruciform hole 8b. That is, a slit shape in which an opening pattern in which “x (cross shape arranged at an inclination of 45 degrees)” is continuously formed at the center position of “+ (cross shape)” in two rows and two columns is formed. It has become.
The shape of each cross-shaped hole 8a, 8b is a shape obtained by combining, for example, a rectangle of about 5 × 50 mm as one straight line portion, and combining the straight line portions vertically and horizontally.
Moreover, the opening of the cross-shaped holes 8a and 8b to the metal plate can be performed by, for example, cutting or processing with a saucer.

  Next, the principle by which the ground metal cover 1 is used to suppress the temperature rise in the panel will be described. FIG. 4 is a diagram schematically showing the copper strip 9 as a conductive portion and the ground metal cover 1 of the present invention, and is an explanatory diagram showing that an eddy current 10 is generated in the ground metal cover 1. When a large current flows through the copper strip 9, a magnetic field is generated around the copper strip 9, and an eddy current 10 is generated in the ground metal cover 1 due to the influence. As described above, the eddy current 10 is one of the factors that increase the temperature in the panel during energization.

  As a countermeasure against temperature rise in the panel, by opening the cross-shaped holes 8a and 8b serving as the slits 8 in FIG. 1 in the ground metal cover 1, the eddy current 10 is grounded as shown in FIG. The metal cover 1 flows in a direction transverse to the plane of the paper (the direction in which the conductive portion arranged close to the ground metal cover 1 extends), but does not flow linearly, but a slit opened in the metal plate It will flow in a zigzag around the shape. As a result, by forming the cross-shaped holes 8a and 8b, the energization path of the eddy current 10 becomes longer than when the eddy current 10 is linear, the electrical resistance increases, and the eddy current 10 can be suppressed small. Therefore, the rise in the panel temperature can be suppressed.

  As shown in FIG. 5, the flow direction of the eddy current 10 generated in the ground metal cover 1 becomes a non-straight line (maze structure) bypassing the cross-shaped holes 8a and 8b, and the eddy current is obtained so as to obtain a necessary resistance value. The size of the opening of the cross-shaped hole 8b is adjusted so as to be as large as possible in the region A so that the ten energization paths can have a sufficient length. As for the opening size of the cruciform hole 8a, when the cruciform holes 8a are arranged in a matrix, the maze structure of the ground metal cover 1 is further improved by adjusting the gap between the patterns while leaving a necessary conductive region. Therefore, the resistance of the energization path of the eddy current 10 can be increased.

  Here, the switchboard 100 often energizes a three-phase alternating current, and it is also assumed that the direction of the eddy current cannot be predicted. However, if the opening pattern of the through hole as shown in FIG. 3 of the first embodiment is formed, the direction other than the eddy current 10 shown in FIG. 5, that is, the vertical direction or the oblique direction with respect to the paper surface of FIG. Even if eddy currents are generated in any direction, the eddy current energization path can be made into a non-linear maze shape, a longer path can be secured than when the energization path is linear, and the eddy current can be reduced. Can be suppressed.

These slits 8 (cross-shaped holes 8a and 8b) also have a function of improving the airflow in the panel and suppressing the temperature rise. Therefore, by using the ground metal cover 1 provided with the slits 8 as a partition plate in the panel, it is possible to suppress the temperature rise in the panel.
It goes without saying that the labyrinth shape of the conductive region of the ground metal cover 1 can be made more complex by reducing the gap between the opening patterns as much as possible.
The ground metal cover 1 of the present invention is not limited to the ground metal cover 1 that separates the bus bar chamber 3 and the cable chamber 7, but can be applied to a partition plate that separates another section and other metal parts that serve as a frame. It is.

In addition, the cross-shaped holes 8a and 8b are shown as an example of the opening shape of the slit 8, but if the opening shape is a combination of a plurality of straight holes, three or more straight lines with different angles are combined. It goes without saying that it is possible to adopt a shape that intersects at one point (for example, * shape).
Here, the ground metal cover 1 has been described as an example where the eddy current is generated. However, the location where the eddy current is generated is not limited to this, and a metal part is installed near the three-phase AC current. All places where it is. For example, a partition plate that partitions the circuit breaker chamber 5 and the cable chamber 7, a metal plate on the back surface of the switchboard 100 on the rear surface side of the external cable 6, and the like.

Embodiment 2. FIG.
Next, the ground metal cover 1 according to the second embodiment will be described. The shape of the cross-shaped holes 8a and 8b shown in FIG. 3 and the like of the above-described first embodiment exemplifies that the vertical and horizontal straight portions have the same length. However, in the ground metal cover 1 of the second embodiment, as shown in FIG. 6, the lengths of the intersecting vertical and horizontal straight portions are different, the vertical (one) straight portion is long, and the horizontal (other) straight portion is A description will be given of short cross-shaped holes 81a and 81b (corresponding to first and second eddy current bypass holes) opened so as to penetrate the metal plate.

In the ground metal cover 1 of FIG. 6, the cross-shaped holes 81b having the same shape are arranged in the same direction in the region A surrounded by the four cross-shaped holes 81a arranged in two rows and two columns with respect to the cross-shaped holes 81a arranged in a matrix. Is arranged. In this example, since the length of the straight portion of the cross in the horizontal direction in the shape of the through hole is shorter than the length, the shape of the region A is also smaller in width than that in FIG.
From another viewpoint, the opening pattern of the through holes in FIG. 6 is such that a plurality of cruciform holes 81a (or 81b) are arranged at equal pitches in the row direction, and the cruciform hole rows are arranged in the row direction and the column direction. It can be said that it is a slit shape arranged with a 1/2 pitch shift.

However, since the ground metal cover 1 illustrated in FIG. 6 has an opening pattern in which the cross-shaped holes 81a and 81b that are long in one direction are opened in the metal plate, the eddy current 10 generated in the ground metal cover 1 in advance. It is effective to adjust the arrangement so that the long side direction of the opening pattern is orthogonal to the flow of the eddy current 10. In other words, the energization path passing through the labyrinth structure formed by the openings of the cross-shaped holes 81a and 81b has a pattern so that sufficient resistance can be obtained by the zigzag energization path through which the eddy current 10 flows as shown in FIG. It is desirable to arrange the ground metal cover 1 in consideration of the arrangement direction.
Therefore, in the ground metal cover 1 in which the cross-shaped holes 81a and 81b having a long opening pattern in one direction shown in FIG. 6 are formed, the conductive portion disposed in the vicinity thereof is a single layer, and the direction of the eddy current generated It can be said that it is effective to apply it when it can be predicted.

In addition, even if an eddy current flows in the vertical direction with respect to the ground metal cover 1 having the opening pattern shown in FIG. 6, the distance is shorter than the energization path indicated by reference numeral 10, but the non-linear unevenness is small. A zigzag energization path is possible.
Similarly to the first embodiment, the ground metal cover 1 according to the second embodiment is not limited to the ground metal cover 1 separating the bus bar chamber 3 and the cable chamber 7, but a partition plate for separating another partition, and other frames It goes without saying that it is also possible to apply to.

Embodiment 3 FIG.
In the first embodiment described above, a pattern arrangement example in which the cruciform hole 8b having the same shape is rotated at an oblique angle of 45 degrees at the center of the area A surrounded by the cruciform holes 8a arranged in two rows and two columns. Was showing. In the third embodiment, FIG. 7 shows an arrangement example of the cross-shaped holes 11 a and 11 b (corresponding to the first and second eddy current bypass holes) opened in the ground metal cover 1 and the holes 12. As shown, a cross-shaped hole 11b having the same shape is disposed in the same direction in a region A surrounded by four cross-shaped holes 11a in two rows and two columns, and further, the cross-shaped hole 11a and the cross-shaped hole 11b The example which opened the hole part 12 in the center part in the area | region B of the plane part of the metal plate enclosed by is shown.

As shown in FIG. 7, when the vertical and horizontal dimensions of the patterns of the cross-shaped holes 11 a and 11 b are the same, it is assumed that eddy current may flow linearly in an oblique direction with respect to the ground metal cover 1. However, by arranging the hole 12 in the region B between the cross-shaped holes 11a and 11b and making the maze shape formed in the ground metal cover 1 more complicated, the eddy current does not flow linearly. can do. That is, when the eddy current flows in an oblique direction, the hole portion 12 is arranged in the region B so as to be an energization path that bypasses the hole portion 12, and the eddy current is suppressed to be small.
In FIG. 7, the hole portion 12 has a square planar shape, but it is needless to say that the hole portion may have another opening shape such as a circular shape.
Here, when the cross-shaped holes 11a and 11b are a pattern obtained by a combination of rectangles of about 5 × 50 mm, the square holes 12 can be formed with a size of about 10 × 10 mm, for example. .

Embodiment 4 FIG.
FIG. 8 is a diagram showing an arrangement example of H-shaped holes 13a and 13b (corresponding to first and second eddy current bypass holes) opened in the ground metal cover 1 according to the fourth embodiment of the present invention. It is. In the above-described first to third embodiments, the shape of the opening pattern opened in the ground metal cover 1 is mainly assumed to be a cross shape (or a shape obtained by deforming a part thereof). In the fourth embodiment, a ground metal cover 1 obtained by combining opening patterns having an alphabetical H shape will be described. As shown in FIG. 8, the ground metal cover 1 has a configuration in which an assembly of H-shaped holes 13a and 13b, which are opening patterns, is disposed on a metal plate. The H-shaped holes 13a and 13b are regularly arranged in the plane portion of the metal plate, the H-shaped holes 13a are continuously arranged at a predetermined pitch in the row direction, and further in a staggered arrangement in the adjacent row direction. The H-shaped holes 13b are arranged with a 1/2 pitch shift with respect to the upper and lower patterns.

That is, as shown in FIG. 8, the ground metal cover 1 according to the fourth embodiment is formed such that the H-shaped holes 13a that are through holes are arranged in a matrix on the surface of the metal plate, and in two rows and two columns. In the region A surrounded by the four H-shaped holes 13a arranged in the shape, an opening pattern in which H-shaped holes 13b that are through holes of the same shape are formed is continuous.
Here, the opening dimensions of the H-shaped holes 13a and 13b are such that the flow direction of the eddy current generated in the ground metal cover 1 is a non-linear line that bypasses the H-shaped holes 13a and 13b, and a necessary resistance value can be secured. Adjusted. That is, by adjusting the distance between the adjacent H-shaped holes 13a to be as small as possible in the region A, the shape of the maze formed in the ground metal cover 1 can be further increased. It becomes possible to make it complicated.

Embodiment 5. FIG.
FIG. 9 is a diagram showing an arrangement example of W-shaped holes 14a and 14b (corresponding to first and second eddy current bypass holes) opened in the ground metal cover 1 according to the fifth embodiment of the present invention. It is. In the fifth embodiment, a ground metal cover 1 obtained by combining opening patterns having an alphabet W shape will be described. As shown in FIG. 9, the ground metal cover 1 has a configuration in which an assembly of W-shaped holes 14a and 14b, which are opening patterns, is disposed on a metal plate. The W-shaped holes 14a and 14b are regularly arranged in the flat portion of the metal plate, and the W-shaped holes 14a are continuously arranged at a predetermined pitch in the row direction, and further in a staggered arrangement in the adjacent row direction. The W-shaped holes 14b are arranged so as to be shifted by 1/2 pitch with respect to the upper and lower patterns.

That is, as shown in FIG. 9, the ground metal cover 1 according to the fifth embodiment is formed such that the W-shaped holes 14 a that are through holes are arranged in a matrix on the surface portion of the metal plate, and in two rows and two columns. In the region A surrounded by the four W-shaped holes 14a arranged in the shape, the opening pattern in which the W-shaped holes 14b, which are through holes of the same shape, are formed is continuous.
Here, the opening dimensions of the W-shaped holes 14a and 14b are such that the direction in which the eddy current generated in the ground metal cover 1 flows becomes a non-linear line bypassing the W-shaped holes 14a and 14b, and a necessary resistance value can be secured. Adjusted. That is, by adjusting the distance between adjacent W-shaped holes 14a to be as small as possible and opening the W-shaped hole 14b in the region A as much as possible, the shape of the maze formed in the ground metal cover 1 can be further increased. It becomes possible to make it complicated.

Embodiment 6 FIG.
In the above-described fifth embodiment, the ground metal cover 1 in which the W-shaped holes 14a and 14b are staggered for bypassing the eddy current has been shown. However, in the sixth embodiment, the opening shape is an alphabet V shape. A case where the V-shaped holes 15a and 15b are disposed in the ground metal cover 1 will be described.
FIG. 10 is a diagram showing an arrangement example of V-shaped holes 15a and 15b (corresponding to first and second eddy current bypass holes) opened in the ground metal cover 1 according to the sixth embodiment of the present invention. It is. As shown in FIG. 10, the ground metal cover 1 has a configuration in which an assembly of V-shaped holes 15a and 15b, which are opening patterns, is arranged on a metal plate. The V-shaped holes 15a and 15b are regularly arranged in the flat portion of the metal plate, the V-shaped holes 15a are continuously arranged at a predetermined pitch in the row direction, and further in a staggered arrangement in the adjacent row direction. The V-shaped hole 15b rotated 90 degrees with a 1/2 pitch shift with respect to the upper and lower patterns is arranged.

That is, as shown in FIG. 10, the ground metal cover 1 according to the sixth embodiment is formed so that V-shaped holes 15a as through holes are arranged in a matrix on the surface of the metal plate, and in two rows and two columns. In the region A surrounded by the four V-shaped holes 15a arranged in the V-shaped hole 15b, which is a through-hole of the same shape, an opening pattern in which the V-shaped hole 15b is inverted and formed downward is continuous.
Here, the opening dimensions of the V-shaped holes 15a and 15b are such that the direction in which the eddy current generated in the ground metal cover 1 flows is a non-linear line that bypasses the V-shaped holes 15a and 15b, and a necessary resistance value can be secured. Adjusted. That is, by adjusting the distance between the adjacent V-shaped holes 15a to be as small as possible in the region A and opening the V-shaped hole 15b as much as possible, the shape of the maze formed in the ground metal cover 1 can be further increased. It becomes possible to make it complicated.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

DESCRIPTION OF SYMBOLS 1 Ground metal cover, 2 busbar, 3 busbar room, 4 circuit breaker, 5 circuit breaker room, 6 external cable, 7 cable room, 8 slit, 8a, 8b, 11a, 11b, 81a, 81b cross-shaped hole, 9 copper strip 10 eddy currents, 12 holes, 13a, 13b H-shaped holes, 14a, 14b W-shaped holes, 15a, 15b V-shaped holes, 100

Claims (11)

  In a metal part that divides the interior of an electric device into a plurality of sections and surrounds a conductive part arranged in each section, an eddy current bypass hole that penetrates the metal plate is provided with respect to the metal plate that constitutes the metal part. A plurality of the eddy current bypass holes are formed, and the eddy current bypass holes are open holes formed by combining a plurality of straight holes that obstruct the path of the eddy current generated in the metal part. Metal parts.   The eddy current bypass hole is an area surrounded by the first eddy current bypass holes arranged in a matrix penetrating the metal plate and the first eddy current bypass holes arranged in two rows and two columns. The metal part according to claim 1, further comprising a second eddy current bypass hole provided therein.   The eddy current bypass hole has an opening dimension adjusted so that a flow direction of eddy current generated in the metal part is a non-linear line bypassing the eddy current bypass hole. The metal part according to claim 2.   The metal part according to claim 2 or 3, wherein the opening shape of the eddy current bypass hole is a cross shape.   5. The metal part according to claim 4, wherein the second eddy current bypass hole is rotated by 45 degrees with respect to the first eddy current bypass hole.   The second eddy current bypass hole is disposed in the same direction as the first eddy current bypass hole, and the first eddy current bypass hole and the second eddy current bypass hole. 5. The ground metal cover according to claim 4, wherein a hole penetrating the metal plate is disposed in a region surrounded by the metal plate.   The metal part according to claim 2 or 3, wherein the opening shape of the eddy current bypass hole is an H shape.   4. The metal part according to claim 2, wherein an opening shape of the eddy current bypass hole is a W shape.   The opening shape of the eddy current bypass hole is V-shaped, and the second eddy current bypass hole is rotated 90 degrees with respect to the arrangement of the first eddy current bypass hole. The metal part according to claim 2 or 3, wherein the metal part is formed.   An electrical apparatus using the metal part according to any one of claims 1 to 9 as a partition plate that divides the inside of the apparatus into partitions.   An electrical apparatus using the metal part according to any one of claims 1 to 9 in a portion where an eddy current is generated by an alternating current.

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