Short circuit device for short circuit test of distribution transformer

Abstract

The utility model discloses a short circuit device for a short circuit test of a distribution transformer, which belongs to the technical field of distribution transformers and comprises a transformer provided with a first-phase high-voltage side, a second-phase high-voltage side, a third-phase high-voltage side and a three-phase low-voltage side corresponding to the three-phase high-voltage side. The three-phase low-voltage side comprises a first-phase low-voltage side, a second-phase low-voltage side and a third-phase low-voltage side, and the three-phase low-voltage side is arranged in a straight line; the short-circuit device comprises a short-circuit bar and three short-circuit parts corresponding to the low-voltage side; the three short-circuit parts are respectively connected with a three-phase low-voltage side; and the short circuit bar is used for conducting the three short circuit parts. According to the technical scheme of the utility model, the problems in the prior art that when a cable is short-circuited, the short-circuit current enables a connecting line to be rapidly heated and generate huge electrodynamic force, so that a cable connector and the cable are damaged by pulling are effectively solved. And meanwhile, a copper bar and bolt connection mode in the prior art cannot meet the short circuit of low-voltage side wiring terminals with different intervals.

Description

Technical Field

[0001] The utility model belongs to the technical field of distribution transformers, and specifically relates to a short-circuit test short-circuit device for distribution transformers. Background Art

[0002] The sudden short-circuit test on a distribution transformer is performed by applying a test voltage to the high-voltage side of the transformer and then short-circuiting the low-voltage side. Because the spacing of the low-voltage terminals on each distribution transformer varies, existing techniques typically use cables to short-circuit the low-voltage side. While this facilitates wiring and solves the problem of varying spacing between low-voltage terminals, the current carrying capacity and connection reliability of cables are far lower than those of copper busbars and bolted connections. Furthermore, when performing a sudden short-circuit test on a distribution transformer, the short-circuit current causes the connecting wires to rapidly heat up, generating a significant electromotive force that can easily damage the cable connectors and cables.

[0003] In order to ensure that the short-circuit test connection is firm and the current carrying capacity meets the requirements, it is most reliable to use copper busbars and bolt connections to perform sudden short-circuit tests on distribution transformers. Utility Model Content

[0004] The purpose of this utility model is to provide a short-circuit test short-circuit device for distribution transformers to address the above-mentioned shortcomings. This device solves the problems that the short-circuit current in the existing technology, when using cables for short-circuiting, causes the connecting wires to heat up rapidly, and also generates huge electric forces, which can tear the cable connectors and cables. In addition, the copper busbar and bolt connection methods of the existing technology cannot meet the short-circuit requirements of low-voltage side terminal blocks with different spacings. To achieve the above-mentioned purpose, the utility model provides the following technical solutions:

[0005] A short-circuit test short-circuit device for a distribution transformer includes a transformer, wherein a first-phase high-voltage side, a second-phase high-voltage side, and a third-phase high-voltage side are provided on the top of the transformer, and three-phase low-voltage sides corresponding to the three-phase high-voltage sides are also provided on the top of the transformer, namely, the first-phase low-voltage side, the second-phase low-voltage side, and the third-phase low-voltage side, wherein the three-phase low-voltage sides are arranged in a straight line, and further includes a short-circuit device; the short-circuit device includes a short-circuit bar and three short-circuit parts corresponding to the low-voltage sides; the three short-circuit parts are respectively connected to the three-phase low-voltage sides;

[0006] The short-circuit bar is used to connect the three short-circuit parts.

[0007] Furthermore, the three short-circuit parts are respectively a first wiring bar, a second wiring bar and a third wiring bar; one end of the first wiring bar is connected to the low-voltage side of the first phase, and the other end is connected to the short-circuit bar;

[0008] One end of the second wiring bank is connected to the second phase low voltage side, and the other end is connected to the shorting bar; one end of the third wiring bank is connected to the third phase low voltage side, and the other end is connected to the shorting bar.

[0009] Furthermore, a waist hole is provided on one end of the second wiring block away from the short-circuit block; the waist hole is arranged along the length direction of the second wiring block; and the second phase low-voltage side can be connected to any position of the waist hole.

[0010] Furthermore, a plurality of circular holes cooperating with the low-voltage side of the second phase are arranged on one end of the second wiring block away from the short-circuit block; and the plurality of circular holes are arranged along the length direction of the second wiring block.

[0011] Furthermore, the shorting bar is arranged perpendicular to the second wiring bar.

[0012] Furthermore, the short-circuit bar is provided with three connecting posts along its length direction; and the first, second and third wiring bars are each provided with through holes matching with the connecting posts at one end close to the short-circuit bar.

[0013] Furthermore, the width of the second wiring bank is slightly greater than that of the first wiring bank and the second wiring bank.

[0014] Furthermore, the first wiring bar, the second wiring bar and the third wiring bar are all copper wiring bars.

[0015] Furthermore, an end of the first wiring bar away from the short-circuit bar is provided with a through hole that cooperates with the low-voltage side of the first phase.

[0016] Furthermore, an end of the third wiring bar away from the short-circuit bar is provided with a through hole that cooperates with the low-voltage side of the third phase.

[0017] The beneficial effects of the utility model are:

[0018] 1. The utility model provides a short-circuit test short-circuit device for distribution transformers. The device adopts a copper busbar and bolt connection method, which avoids the short-circuit current causing the connecting wire to heat up rapidly when the cable is short-circuited. At the same time, it also generates huge electric force. The strong electric force can easily tear the cable connector and cable. It is safer and the connection is simpler and more reliable.

[0019] 2. The utility model provides a short-circuit test short-circuit device for a distribution transformer. By setting the waist hole on the second terminal block and the setting of multiple round holes, it can adapt to various situations with different spacings between low-voltage side terminal blocks. It has a simple structure and wide adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of the utility model;

[0021] Figure 2 This is another structural diagram of the utility model;

[0022] Figure 3 yes Figure 1Schematic diagram of the structure where the waist hole on the second terminal block is replaced with multiple round holes;

[0023] Figure 4 yes Figure 2 Schematic diagram of the structure where the waist hole on the second terminal block is replaced with multiple round holes;

[0024] In the accompanying drawings: 1-transformer, 2-first phase high voltage side, 3-second phase high voltage side, 4-third phase high voltage side, 5-first phase low voltage side, 6-second phase low voltage side, 7-third phase low voltage side, 8-short-circuit bar, 9-first terminal bar, 10-second terminal bar, 11-third terminal bar, 12-waist hole, 13-connecting column. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation methods, but the present invention is not limited to the following embodiments.

[0026] Example 1:

[0027] See attached Figures 1 to 4A short-circuit test short-circuit device for a distribution transformer includes a transformer 1. The top of the transformer 1 is provided with a first-phase high-voltage side 2, a second-phase high-voltage side 3, and a third-phase high-voltage side 4. The top of the transformer 1 is also provided with three-phase low-voltage sides corresponding to the three-phase high-voltage sides, namely, a first-phase low-voltage side 5, a second-phase low-voltage side 6, and a third-phase low-voltage side 7. The three-phase low-voltage sides are arranged in a straight line. The short-circuit device also includes a short-circuit device; the short-circuit device includes a short-circuit bar 8 and three short-circuit parts corresponding to the low-voltage sides; the three short-circuit parts are respectively connected to the three-phase low-voltage sides; the short-circuit bar 8 is used to connect the three short-circuit parts. The utility model provides a short-circuit test short-circuiting device for a distribution transformer. Different transformers 1 have different numbers of high-voltage sides and low-voltage sides, while the numbers of high-voltage sides and low-voltage sides on each transformer 1 correspond one to one, and the spacing between each low-voltage side is the same. The transformer 1 of this embodiment includes a first-phase high-voltage side 2, a second-phase high-voltage side 3, and a third-phase high-voltage side 4, that is, an A-phase terminal, a B-phase terminal, and a C-phase terminal; the corresponding transformer 1 is provided with a first-phase low-voltage side 5, a second-phase low-voltage side 6, and a third-phase low-voltage side 7, that is, an A-phase terminal, a B-phase terminal, and a C-phase terminal. The short-circuit device includes a short-circuit part and a short-circuit bar 8. The number of the short-circuit parts is consistent with the number of terminals on the low-voltage side of the transformer 1, that is, it includes three short-circuits. One end of the three short-circuits is connected to the a-phase, b-phase, and c-phase terminals respectively, and the other end connects the three short-circuits to the short-circuit bar 8. The connection method of the short-circuit parts to the a-phase, b-phase, and c-phase terminals can be connected by a bolt structure. At the same time, the connection method of the short-circuit parts and the short-circuit bar 8 is also a bolt structure connection. When performing a short-circuit test, a test voltage is applied to the high-voltage side, and the low-voltage side is short-circuited by the short-circuit part and the short-circuit bar 8. The three short-circuit parts and the short-circuit bar 8 are all long copper bars, which have sufficient current carrying capacity compared to cables. The utility model replaces the cable connection with the long copper bar, and the short-circuit device of the long copper bar is fixedly connected to the bolts of the a-phase, b-phase, and c-phase terminals, which meets the requirements of firmness and current carrying capacity, and is more reliable than cable line testing.

[0028] Example 2:

[0029] See attached Figures 1 to 4 . Based on the first embodiment, the three short-circuit parts are respectively the first wiring bar 9, the second wiring bar 10 and the third wiring bar 11; the first wiring bar 9 is connected to the first phase low-voltage side 5 at one end and to the short-circuit bar 8 at the other end; the second wiring bar 10 is connected to the second phase low-voltage side 6 at one end and to the short-circuit bar 8 at the other end; the third wiring bar 11 is connected to the third phase low-voltage side 7 at one end and to the short-circuit bar 8 at the other end. The three short-circuit parts are respectively the first, second and third wiring bars 11, which are respectively connected to the first, second and third phase low-voltage sides 7, and then the other ends are all connected to the short-circuit bar 8.

[0030] A waist hole 12 is provided on the end of the second wiring bar 10 away from the shorting bar 8; the waist hole 12 is arranged along the length direction of the second wiring bar 10; the second phase low-voltage side 6 can be connected to any position of the waist hole 12. Furthermore, in order to adapt to the different spacings between the low-voltage side limit terminals on different transformers 1, an adjustable hole is provided on the second wiring bar 10. In this embodiment, the waist hole 12 is preferably arranged along its length direction. The first wiring bar 9 and the third wiring bar 11 are respectively located on both sides of the second wiring bar 10, as shown in the attached figure. Figure 2 As shown, when the spacing between the terminals on the low-voltage side increases, the position of the phase b terminal in the waist hole 12 is adjusted, and the connection between the first terminal block 9 and the third terminal block 11 and the phase a and phase c terminals is further adjusted. That is, the first terminal block 9 and the third terminal block 11 are respectively rotated to a certain angle on both sides of the second terminal block 10 with the point of connection with the shorting bar 8 as the center of the circle, and the shorting bar 8 is gradually moved closer to the transformer 1 until the ends of the first terminal block 9 and the third terminal block 11 away from the shorting bar 8 can be fixed on the phase a and phase c terminals respectively. The length of the waist hole 12 can match the short-circuit test of various transformers 1 with different spacing on the low-voltage side, and has a wider range of applications. Since the waist hole 12 is set on the second terminal block 10, its current carrying capacity will be relatively reduced. Based on this, the width of the second terminal block 10 is set slightly larger than the first and third terminal blocks 11 to keep their current carrying capacity basically consistent.

[0031] Example 3:

[0032] See attached Figures 1 to 4 . On the basis of the second embodiment, a plurality of circular holes cooperating with the second phase low-voltage side 6 are arranged on the end of the second terminal block 10 away from the short-circuit bar 8; the plurality of circular holes are arranged along the length direction of the second terminal block 10. The adjustment hole in the first embodiment is replaced by a plurality of circular holes evenly arranged along the length direction of the second terminal block 10, and the plurality of circular holes are arranged at the end away from the short-circuit bar 8, and the plurality of circular holes can be connected with the b-phase terminal. It can also adapt to the short-circuit test of a plurality of transformers 1 with different spacings between the low-voltage side terminals. The implementation method is also to first connect the appropriate circular holes on the second terminal block 10 with the b-phase terminal, and then correspondingly rotate the first terminal block 9 and the second terminal block 10 to the appropriate angle to achieve connection with the a-phase and c-phase terminals. Compared with the waist hole 12 structure, the connection between the second terminal block 10 and the b-phase terminal is more firm and reliable in this method, which can only adapt to a few low-voltage side terminals of the transformer 1 with fixed spacing.

[0033] The shorting bar 8 is arranged perpendicularly to the second terminal block 10. Preferably, the second terminal block 10 is always arranged perpendicularly to the shorting bar 8, and the arrangement direction of the waist hole 12 and the round hole on the second terminal block 10 is also arranged perpendicularly to the shorting bar 8. When connecting with several low-voltage side terminals of the transformer 1 with different spacings, the operation steps are simpler. The waist hole 12 or the round hole on the second terminal block 10 is directly matched with the b-phase terminal and is movable. Then, the first terminal block 9 or the third terminal block 11 is adjusted to connect with its corresponding low-voltage side terminal respectively. When the first terminal block 9 or the third terminal block 11 can be connected to the corresponding terminal, the terminal block on the other side of the corresponding first terminal block 9 can also be connected to its corresponding low-voltage side terminal. The b-phase terminal and the second terminal block 10 are fixed, and then the first and third terminal blocks 11 are fixed.

[0034] The short-circuit bar 8 is provided with three connecting columns 13 along its length direction; the first, second and third terminal blocks 11 are provided with through holes that cooperate with the connecting columns 13 on one end close to the short-circuit bar 8. The short-circuit bar 8 is provided with three connecting columns 13, and the spacing is the same. The preferred short-circuit bar 8 also adopts a long copper bar, and its length direction is perpendicular to the length direction of the second terminal block 10. The three connecting columns 13 are respectively connected to the corresponding first, second and third terminal blocks 11. The connecting columns 13 are provided with external threads, which pass through the through holes on the corresponding first terminal block 9, second terminal block 10 and third terminal block 11, and are then rotated and fixed by bolts; before adjusting to the appropriate position, do not tighten the bolts to reserve space for movement until the first terminal block 9 and the third terminal block 11 are adjusted to the appropriate position, and then tighten and fix them.

[0035] The width of the second wiring bar 10 is slightly greater than that of the first wiring bar 9 and the second wiring bar 10. Since the second wiring bar 10 is provided with adjustment holes, such as waist holes 12 or multiple round holes, the effective area of the second wiring bar 10 is reduced. Therefore, the width of the second wiring bar 10 is slightly greater than that of the first wiring bar 9 and the third wiring bar 11 to ensure that the current carrying capacity of the three wiring bars is equivalent.

[0036] The first wiring bar 9, the second wiring bar 10 and the third wiring bar 11 are all copper wiring bars. The shorting bar 8 is also preferably a copper bar, which has good electrical conductivity and can carry current, and is a commonly used material for shorting tests.

[0037] The end of the first terminal block 9 away from the short-circuit block 8 is provided with a through hole that cooperates with the first phase low-voltage side 5; the end of the third terminal block 11 away from the short-circuit block 8 is provided with a through hole that cooperates with the third phase low-voltage side 7. The a-phase terminal, the b-phase terminal and the c-phase terminal are all protruding conductive columns, and an external thread structure is provided on the conductive column. The a-phase terminal passes through the through hole on the end of the first terminal block 9 away from the short-circuit block 8 and is then fixedly connected by a thread; the b-phase terminal passes through the waist hole 12 or round hole on the second terminal block 10 and is fixedly connected by a bolt; the c-phase terminal passes through the through hole on the end of the third terminal block 11 away from the short-circuit block 8 and is then fixedly connected by a bolt.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the present invention.

[0039] In the description of the present invention, "first feature" and "second feature" may include one or more such features.

[0040] In the description of the present invention, “plurality” means two or more.

[0041] In the description of the present invention, a first feature being “above” or “below” a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact via another feature therebetween.

[0042] In the description of the present invention, a first feature “above”, “above” and “above” a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature.

[0043] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," and "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the illustrative use of these terms does not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0044] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A short-circuit test short-circuit device for a distribution transformer, comprising a transformer (1), wherein a first-phase high-voltage side (2), a second-phase high-voltage side (3), and a third-phase high-voltage side (4) are provided on the top of the transformer (1), and three-phase low-voltage sides corresponding to the three-phase high-voltage sides, namely, a first-phase low-voltage side (5), a second-phase low-voltage side (6), and a third-phase low-voltage side (7), are further provided on the top of the transformer (1), wherein the three-phase low-voltage sides are arranged in a straight line, and wherein: It also includes a short-circuit device; the short-circuit device includes a short-circuit bar (8) and three short-circuit parts corresponding to the low-voltage side; the three short-circuit parts are respectively connected to the three-phase low-voltage side; the short-circuit bar (8) is used to connect the three short-circuit parts.

2. A short-circuit test short-circuit device for a distribution transformer according to claim 1, characterized in that: The three short-circuit parts are respectively a first wiring block (9), a second wiring block (10) and a third wiring block (11); one end of the first wiring block (9) is connected to the first phase low-voltage side (5), and the other end is connected to the short-circuit block (8); one end of the second wiring block (10) is connected to the second phase low-voltage side (6), and the other end is connected to the short-circuit block (8); one end of the third wiring block (11) is connected to the third phase low-voltage side (7), and the other end is connected to the short-circuit block (8).

3. A short-circuit test short-circuit device for a distribution transformer according to claim 2, characterized in that: A waist hole (12) is provided on one end of the second wiring bar (10) away from the short-circuit bar (8); the waist hole (12) is arranged along the length direction of the second wiring bar (10); and the second-phase low-voltage side (6) can be connected to any position of the waist hole (12).

4. A short-circuit test short-circuit device for a distribution transformer according to claim 2, characterized in that: A plurality of circular holes cooperating with the second phase low-voltage side (6) are arranged on one end of the second wiring bar (10) away from the short-circuit bar (8); the plurality of circular holes are arranged along the length direction of the second wiring bar (10).

5. A short-circuit test short-circuit device for a distribution transformer according to claim 2, characterized in that: The short-circuit bar (8) and the second wiring bar (10) are arranged vertically.

6. A short-circuit test short-circuit device for a distribution transformer according to claim 2, characterized in that: The short-circuit bar (8) is provided with three connecting columns (13) along its length direction; and the first, second and third wiring bars (11) are each provided with through holes matching the connecting columns (13) at one end close to the short-circuit bar (8).

7. A short-circuit test short-circuit device for a distribution transformer according to claim 2, characterized in that: The width of the second wiring row (10) is slightly greater than that of the first wiring row (9) and the second wiring row (10).

8. A short-circuit test short-circuit device for a distribution transformer according to claim 2, characterized in that: The first wiring bar (9), the second wiring bar (10) and the third wiring bar (11) are all copper wiring bars.

9. A short-circuit test short-circuit device for a distribution transformer according to claim 2, characterized in that: An end of the first wiring bar (9) away from the short-circuit bar (8) is provided with a through hole that cooperates with the first phase low-voltage side (5).

10. A short-circuit test short-circuit device for a distribution transformer according to claim 2, characterized in that: An end of the third wiring bar (11) away from the short-circuit bar (8) is provided with a through hole that cooperates with the third phase low-voltage side (7).

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