A short-circuiting device for a distribution transformer

Abstract

The present invention relates to the technical field of electrical testing of 10kV voltage level distribution transformers, and discloses a short-circuiting device for distribution transformers. The short-circuiting device for distribution transformers includes a short-circuiting mechanism, and the short-circuiting mechanism includes a short-circuiting copper bar, a first lifting assembly, and three wiring copper bars. The three wiring copper bars can be connected to the A-phase terminal, the B-phase terminal, and the C-phase terminal of the distribution transformer respectively; the short-circuiting copper bar can be connected to the 0-phase terminal of the distribution transformer, and the wiring copper bar is located above the short-circuiting copper bar; the short-circuiting copper bar is installed on the first lifting assembly, and the first lifting assembly drives the short-circuiting copper bar to rise and fall to control the on and off of the short-circuiting copper bar and the wiring copper bar. The present invention realizes the automatic disconnection and short-circuiting of the distribution transformer, does not require manual repeated disconnection and wiring, saves a lot of wiring and disconnection time of the test personnel, improves the test efficiency, and realizes one-time wiring to automatically complete all distribution transformer electrical tests.

Description

Technical Field

[0001] The invention relates to the technical field of electrical testing of 10kV voltage level distribution transformers, and in particular to a short-circuiting device for distribution transformers. Background Art

[0002] At present, high-voltage electrical tests such as winding-to-ground and inter-winding DC insulation resistance measurement, absorption ratio measurement, dielectric loss factor (tanδ) measurement of insulation system capacitance (applicable to oil-immersed transformers), winding-to-ground and inter-winding capacitance measurement, winding resistance measurement, voltage ratio measurement and connection group number verification, no-load loss and no-load current measurement, short-circuit impedance and load loss measurement, externally applied voltage withstand test, induced voltage withstand test, temperature rise test, no-load loss and no-load current measurement at 90% and 110% rated voltage, short-time overload capacity test (applicable to oil-immersed transformers), and three-phase transformer zero-sequence impedance measurement (applicable to oil-immersed transformers) of 10kV voltage level distribution transformers require manual wiring and disconnection for more than 15 times. The test process requires a lot of manual cooperation, and the test sequence is cumbersome and complicated.

[0003] Based on this, there is an urgent need for a short-circuiting device for a distribution transformer to solve the above-mentioned problems. Summary of the invention

[0004] Based on the above, the purpose of the present invention is to provide a short-circuiting device for a distribution transformer, which realizes automatic disconnection and short-circuiting of the distribution transformer, does not require manual repeated disconnection and wiring, saves a lot of wiring and disconnection time of test personnel, and improves test efficiency.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A short-circuiting device for a distribution transformer, which is used to disconnect and short-circuit the distribution transformer, the short-circuiting device for the distribution transformer comprises a short-circuiting mechanism, and the short-circuiting mechanism comprises:

[0007] Three copper busbars, which can be connected to the A-phase terminal, the B-phase terminal and the C-phase terminal of the distribution transformer respectively;

[0008] A short-circuit copper bar, which can be connected to the 0-phase terminal of the distribution transformer, and the connection copper bar is located above the short-circuit copper bar;

[0009] A first lifting component, the short-circuit copper bar is installed on the first lifting component, and the first lifting component drives the short-circuit copper bar to rise and fall to control the connection and disconnection of the short-circuit copper bar and the connection copper bar.

[0010] As a preferred technical solution for a short-circuiting device of a distribution transformer, the first lifting assembly includes a side panel, a first electric push rod and a connecting plate, the first electric push rod is installed on the side panel, the output end of the first electric push rod is fixed to the connecting plate, and the short-circuiting copper bus is fixed to the connecting plate.

[0011] As a preferred technical solution for a short-circuiting device of a distribution transformer, the short-circuiting mechanism also includes a shell and an elastic component, the elastic component is fixed in the shell, the side wall of the shell is provided with a first through hole, the wiring copper busbar is passed through the first through hole and installed under the elastic component, when the first lifting component drives the short-circuiting copper busbar to rise, the three wiring copper busbars are attached to the short-circuiting copper busbar under the elastic force of the elastic component.

[0012] As a preferred technical solution for a short-circuiting device of a distribution transformer, the elastic component includes a fixed plate, a sliding rod and a spring. The fixed plate is fixed in the shell, the fixed plate is provided with a sliding hole, the sliding rod is passed through the sliding hole, a limiting portion is provided at the top end of the sliding rod, the limiting portion prevents the sliding rod from detaching from the fixed plate, the bottom end of the sliding rod fixes the wiring copper busbar, the spring is sleeved on the sliding rod, and one end abuts against the fixed plate, and the other end abuts against the wiring copper busbar.

[0013] As a preferred technical solution for a short-circuit device of a distribution transformer, a fan fixing hole is provided on the side wall of the shell, a cooling fan is installed in the fan fixing hole, and the fan fixing hole is arranged opposite to the first through hole.

[0014] As a preferred technical solution for a short-circuiting device of a distribution transformer, the short-circuiting mechanism further includes an insulating sheet, and the insulating sheet is located between the wiring copper busbar and the side wall of the shell.

[0015] As a preferred technical solution for a short-circuiting device of a distribution transformer, it also includes a base and a second lifting assembly, wherein the second lifting assembly is installed on the base, and the short-circuiting mechanism is detachably installed above the second lifting assembly.

[0016] As a preferred technical solution for a short-circuiting device of a distribution transformer, a universal wheel is provided at the bottom of the base.

[0017] As a preferred technical solution for a short-circuiting device of a distribution transformer, a side wall of the base is provided with a wire groove for accommodating cables; and a handle is also provided on the side wall of the base.

[0018] As an optimal technical solution for the short-circuiting device of a distribution transformer, the base is also provided with a communication interface, and the short-circuiting device of the distribution transformer is connected to an external intelligent test and detection station through the communication interface, so that the intelligent test and detection station can control the first lifting assembly and the second lifting assembly.

[0019] The beneficial effects of the present invention are:

[0020] The present invention provides a short-circuiting device for a distribution transformer, which is used for short-circuiting a distribution transformer. When working, three copper bars are respectively connected to the A-phase terminal, the B-phase terminal and the C-phase terminal of the distribution transformer through cables; the short-circuiting copper bar is connected to the 0-phase terminal of the distribution transformer through cables. When the first lifting component drives the short-circuiting copper bar to rise, so that the upper surface of the short-circuiting copper bar is attached to the lower surfaces of the three copper bars, at this time, the short-circuiting of the distribution transformer is achieved; when the first lifting component drives the short-circuiting copper bar to descend, so that the upper surface of the short-circuiting copper bar is separated from the lower surface of the copper bar, at this time, the disconnection of the distribution transformer is achieved. The present invention realizes automatic disconnection and short-circuiting of the distribution transformer, does not require manual repeated disconnection, saves a lot of time for test personnel in wiring and disconnection, improves test efficiency, and realizes one-time wiring to automatically complete all electrical tests of the distribution transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0022] Figure 1 It is a structural schematic diagram of a short-circuit device for a distribution transformer provided in a specific embodiment of the present invention;

[0023] Figure 2 It is a partial structural schematic diagram of a short-circuit device of a distribution transformer provided in a specific embodiment of the present invention;

[0024] Figure 3 It is a structural schematic diagram of a short-circuit mechanism provided in a specific embodiment of the present invention;

[0025] Figure 4 is a structural exploded diagram of a short-circuit mechanism provided in a specific embodiment of the present invention from a first perspective;

[0026] Figure 5 It is a structural explosion diagram from a second perspective of the short-circuit mechanism provided in a specific embodiment of the present invention.

[0027] The following are marked in the figure:

[0028] 1. Short-circuit mechanism; 11. Wiring copper bar; 111. Insulating sheet; 12. Short-circuit copper bar; 13. First lifting assembly; 131. Side plate; 1311. Bottom bracket; 1312. Clamp; 132. First electric push rod; 133. Connecting plate; 14. Shell; 141. Fan fixing hole; 142. Heightening boss; 143. Handle; 15. Elastic assembly; 151. Fixing plate; 152. Sliding rod; 1521. Limiting part; 153. Spring;

[0029] 2. Base; 21. Universal wheel; 22. Wire slot; 23. Handle; 24. Communication interface;

[0030] 3. The second lifting assembly. DETAILED DESCRIPTION

[0031] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0032] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] In the present invention, unless otherwise clearly specified and limited, 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 through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0034] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0035] like Figure 1-Figure 5 As shown, this embodiment provides a short-circuiting device for a distribution transformer, which includes a short-circuiting mechanism 1. The short-circuiting mechanism 1 includes a short-circuiting copper busbar 12, a first lifting assembly 13 and three connecting copper busbars 11, which are used to disconnect and short-circuit the distribution transformer.

[0036] Specifically, Figure 2 and Figure 3 As shown, three copper bars 11 can be connected to the A-phase terminal, B-phase terminal and C-phase terminal of the distribution transformer respectively; the shorting copper bar 12 can be connected to the 0-phase terminal of the distribution transformer, and the copper bar 11 is located above the shorting copper bar 12; the shorting copper bar 12 is installed on the first lifting component 13, and the first lifting component 13 drives the shorting copper bar 12 to rise and fall to control the on and off of the shorting copper bar 12 and the copper bar 11. The shorting device of the distribution transformer of this embodiment is applied to a 10KV distribution transformer.

[0037] During operation, the three copper bars 11 are respectively connected to the A-phase terminal, the B-phase terminal and the C-phase terminal of the distribution transformer through cables; the short-circuit copper bar 12 is connected to the 0-phase terminal of the distribution transformer through cables. When the first lifting component 13 drives the short-circuit copper bar 12 to rise, so that the upper surface of the short-circuit copper bar 12 fits the lower surface of the copper bar 11, at this time, the short-circuit of the distribution transformer is achieved; when the first lifting component 13 drives the short-circuit copper bar 12 to descend, so that the upper surface of the short-circuit copper bar 12 is separated from the lower surface of the copper bar 11, at this time, the distribution transformer is disconnected. This embodiment realizes the automatic disconnection and short-circuiting of the distribution transformer, does not require manual repeated disconnection, saves a lot of time for test personnel in wiring and disconnection, improves test efficiency, and realizes one-time wiring to automatically complete all distribution transformer electrical tests.

[0038] Among them, the electrical tests applicable to this embodiment include the measurement of the DC insulation resistance of the winding to the ground and between the windings of the 10kV voltage level distribution transformer, the measurement of the absorption ratio, the measurement of the dielectric loss factor (tanδ) of the insulation system capacitance (applicable to oil-immersed transformers), the measurement of the capacitance of the winding to the ground and between the windings, the measurement of the winding resistance, the voltage ratio measurement and the verification of the connection group number, the measurement of the no-load loss and no-load current, the measurement of the short-circuit impedance and the load loss, the externally applied voltage withstand test, the induced voltage withstand test, the temperature rise test, the measurement of the no-load loss and no-load current at 90% and 110% of the rated voltage, the short-time overload capacity test (applicable to oil-immersed transformers), the measurement of the zero-sequence impedance of the three-phase transformer (applicable to oil-immersed transformers) and other high-voltage electrical tests.

[0039] Preferably, if Figure 3 and Figure 4 As shown, the first lifting assembly 13 includes a side plate 131, a first electric push rod 132 and a connecting plate 133. The first electric push rod 132 is mounted on the side plate 131. The output end of the first electric push rod 132 is fixed to the connecting plate 133. The short-circuit copper bar 12 is inserted into the second through hole of the housing 14, and the short-circuit copper bar 12 is fixed to the connecting plate 133. In this embodiment, a bottom bracket 1311 is mounted on the side plate 131 by screws, the bottom of the first electric push rod 132 is mounted on the bottom bracket 1311, the first electric push rod 132 is fixed to the side plate 131 by a clamp 1312 and screws to achieve the fixation of the first electric push rod 132, the connecting plate 133 is fixed to the output end of the first electric push rod 132 by screws, and the short-circuit copper bar 12 is fixed to the connecting plate 133 by screws. Further preferably, the first electric push rod 132 is divided into two groups, which are fixed to the side plate 131 at intervals to improve the stability of the lifting and lowering of the short-circuit copper bar 12.

[0040] Alternatively, if Figure 2-Figure 4 As shown, the short-circuit mechanism 1 also includes a housing 14 and an elastic component 15. The elastic component 15 is fixed in the housing 14. The side wall of the housing 14 is provided with a first through hole. The wiring copper bar 11 is passed through the first through hole and installed below the elastic component 15. When the first lifting component 13 drives the short-circuit copper bar 12 to rise, the three wiring copper bars 11 are attached to the short-circuit copper bar 12 under the elastic force of the elastic component 15. Under the elastic force of the elastic component 15, the three wiring copper bars 11 better contact the short-circuit copper bar 12 to prevent the short-circuit copper bar 12 from being unable to contact the three wiring copper bars 11 at the same time when the three wiring copper bars 11 are at different heights, thereby improving the reliability of the circuit connection.

[0041] Further preferably, the elastic component 15 includes a fixed plate 151, a slide bar 152 and a spring 153. The fixed plate 151 is fixed in the housing 14. The fixed plate 151 is provided with a slide hole. The slide bar 152 is inserted into the slide hole. A limit portion 1521 is provided at the top of the slide bar 152. The limit portion 1521 prevents the slide bar 152 from being separated from the fixed plate 151. The bottom end of the slide bar 152 is fixed to the wiring copper bar 11. The spring 153 is sleeved on the slide bar 152, and one end abuts against the fixed plate 151, and the other end abuts against the wiring copper bar 11. When the short-circuit copper bar 12 is upwardly attached to the wiring copper bar 11, the spring 153 can be slightly compressed and deformed to improve the reliability of the circuit connection.

[0042] Further preferably, the side wall of the housing 14 is provided with a fan fixing hole 141, a cooling fan is installed in the fan fixing hole 141, and the fan fixing hole 141 is arranged opposite to the first through hole to improve the heat dissipation of the short-circuit mechanism 1 when it is working. In this embodiment, there are three fan fixing holes 141, and the three fan fixing holes 141 correspond to the positions of the three wiring copper bars 11 one by one.

[0043] Since the copper busbar 11 is fixed on the elastic component 15, when the copper busbar 11 is connected to the cable, the gravity increases and the copper busbar 11 is tilted and deformed. Preferably, the short-circuit mechanism 1 also includes an insulating sheet 111, which is located between the copper busbar 11 and the side wall of the housing 14. When the copper busbar 11 is tilted and deformed to contact the housing 14, the insulating sheet 111 implements circuit insulation between the copper busbar 11 and the housing 14 to prevent the risk of electric shock to the test personnel.

[0044] Furthermore, the short-circuit device of the distribution transformer also includes a base 2 and a second lifting assembly 3, the second lifting assembly 3 is installed on the base 2, and the short-circuit mechanism 1 is detachably installed above the second lifting assembly 3. The second lifting assembly 3 can drive the short-circuit mechanism 1 to rise and fall, so that the height of the short-circuit mechanism 1 matches the wiring height of the distribution transformer, reducing the cable length and facilitating the wiring of the short-circuit mechanism 1. Of course, the short-circuit structure can also be removed from the second lifting assembly 3 and used alone for electrical testing of the distribution transformer. Figure 5 As shown, when the short-circuit mechanism 1 is used alone, two raised bosses 142 are arranged at intervals on the outer wall of the housing 14 on the side where the fan fixing hole 141 is provided, and the side of the housing 14 where the cooling fan is installed is placed on a workbench. The two raised bosses 142 can increase the distance between the housing 14 and the workbench, on the one hand, preventing the cooling fan from contacting the workbench, and on the other hand, increasing the heat dissipation performance of the cooling fan. Further preferably, a handle 143 is provided on the housing 14 to facilitate carrying and moving the short-circuit mechanism 1.

[0045] like Figure 1As shown, in this embodiment, the second lifting assembly 3 is a second electric push rod mechanism, and the output end of the second electric push rod is provided with a fixed seat, and the short-circuit mechanism 1 is detachably mounted on the fixed seat. In other embodiments, the first lifting assembly 13 and the second lifting assembly 3 can also be a motor screw lifting device, a cylinder or an oil cylinder lifting device. The motor screw lifting device, the cylinder or the oil cylinder lifting device are common technical means applied in the prior art, and their structure and working principle will not be described in detail here.

[0046] Preferably, universal wheels 21 are provided at the bottom of the base 2. In this embodiment, there are four universal wheels 21, which are evenly distributed at the four corners of the bottom of the base 2 to improve the mobility of the short-circuit device of the distribution transformer.

[0047] Preferably, the side wall of the base 2 is provided with a wire groove 22 for accommodating cables. When the short-circuit device of the distribution transformer is in an unconnected state, the cable of the short-circuit device of the distribution transformer can be placed in the wire groove 22, which is convenient for accommodating the cable. The side wall of the base 2 is also provided with a handle 23, which is convenient for the test personnel to drag the short-circuit device of the distribution transformer to move.

[0048] Further preferably, the base 2 is also provided with a communication interface 24, and the short-circuiting device of the distribution transformer is connected to an external intelligent test and detection station through the communication interface 24, so that the intelligent test and detection station can control the first lifting assembly 13 and the second lifting assembly 3, thereby realizing the intelligent test and detection station automatically controlling the short-circuiting and disconnecting of the distribution transformer.

[0049] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A short-circuiting device for a distribution transformer, which is used to disconnect and short-circuit a distribution transformer, characterized in that: The short-circuiting device of the distribution transformer comprises a short-circuiting mechanism (1), and the short-circuiting mechanism (1) comprises: Three copper busbars (11), the three copper busbars (11) being respectively connectable to the A-phase terminal, the B-phase terminal and the C-phase terminal of the distribution transformer; A short-circuit copper busbar (12) which can be connected to the 0-phase terminal of the distribution transformer, and the connection copper busbar (11) is located above the short-circuit copper busbar (12); A first lifting component (13), the short-circuit copper bar (12) is mounted on the first lifting component (13), and the first lifting component (13) drives the short-circuit copper bar (12) to rise and fall, so as to control the connection and disconnection of the short-circuit copper bar (12) and the connection copper bar (11); when the first lifting component (13) drives the short-circuit copper bar (12) to rise, so that the upper surface of the short-circuit copper bar (12) is attached to the lower surfaces of the three connection copper bars (11), at this time, the short-circuit of the distribution transformer is achieved; when the first lifting component (13) drives the short-circuit copper bar (12) to fall, so that the upper surface of the short-circuit copper bar (12) is separated from the lower surface of the connection copper bar (11), at this time, the disconnection of the distribution transformer is achieved.

2. The short-circuiting device for a distribution transformer according to claim 1, characterized in that: The first lifting assembly (13) comprises a side plate (131), a first electric push rod (132) and a connecting plate (133); the first electric push rod (132) is mounted on the side plate (131); the output end of the first electric push rod (132) is fixed to the connecting plate (133); and the short-circuit copper busbar (12) is fixed to the connecting plate (133).

3. The short-circuiting device for a distribution transformer according to claim 1, characterized in that: The short-circuit mechanism (1) further comprises a shell (14) and an elastic component (15), wherein the elastic component (15) is fixed in the shell (14), a first through hole is provided on a side wall of the shell (14), the wiring copper busbar (11) is passed through the first through hole and is installed below the elastic component (15), and when the first lifting component (13) drives the short-circuit copper busbar (12) to rise, the three wiring copper busbars (11) are attached to the short-circuit copper busbar (12) under the elastic force of the elastic component (15).

4. The short-circuiting device for a distribution transformer according to claim 3, characterized in that: The elastic component (15) comprises a fixed plate (151), a sliding rod (152) and a spring (153); the fixed plate (151) is fixed in the housing (14); the fixed plate (151) is provided with a sliding hole; the sliding rod (152) is inserted into the sliding hole; a limiting portion (1521) is provided at the top end of the sliding rod (152); the limiting portion (1521) prevents the sliding rod (152) from detaching from the fixed plate (151); the bottom end of the sliding rod (152) is fixed to the wiring copper busbar (11); the spring (153) is sleeved on the sliding rod (152), and one end of the spring abuts against the fixed plate (151) and the other end abuts against the wiring copper busbar (11).

5. The short-circuiting device for a distribution transformer according to claim 3, characterized in that: A fan fixing hole (141) is provided on the side wall of the housing (14), a heat dissipation fan is installed in the fan fixing hole (141), and the fan fixing hole (141) is arranged opposite to the first through hole.

6. The short-circuiting device for a distribution transformer according to claim 3, characterized in that: The short-circuit mechanism (1) further comprises an insulating sheet (111), wherein the insulating sheet (111) is located between the wiring copper bar (11) and the side wall of the housing (14).

7. The short-circuiting device for a distribution transformer according to claim 1, characterized in that: It also comprises a base (2) and a second lifting assembly (3), wherein the second lifting assembly (3) is mounted on the base (2), and the short-circuit mechanism (1) is detachably mounted above the second lifting assembly (3).

8. The short-circuiting device for a distribution transformer according to claim 7, characterized in that: The bottom of the base (2) is provided with a universal wheel (21).

9. The short-circuiting device for a distribution transformer according to claim 7, characterized in that: The side wall of the base (2) is provided with a wire groove (22), and the wire groove (22) is used to accommodate cables; the side wall of the base (2) is also provided with a handle (23).

10. The short-circuiting device for a distribution transformer according to claim 7, characterized in that: The base (2) is also provided with a communication interface (24), and the short-circuiting device of the distribution transformer is connected to an external intelligent test and detection station via the communication interface (24), so that the intelligent test and detection station can control the first lifting assembly (13) and the second lifting assembly (3).

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