A lightning protection device for distribution transformers

Abstract

The application relates to the technical field of lightning protection devices, and discloses a lightning protection device for a distribution transformer, which comprises a distribution transformer body, and is provided with two explosion-proof membrane plates fixedly sleeved at the top and bottom of the outer wall of the distribution transformer body. The lightning protection mechanism comprises two post insulators fixedly installed between the right sides of the two explosion-proof membrane plates, two metal fittings I fixedly installed at the top ends of the two post insulators, two metal fittings II fixedly installed at the bottom ends of the two post insulators, and the metal fittings I are fixedly penetrated through the explosion-proof membrane plates above and continue to extend upwards. High voltage is guided to the ground along the steel legs through the four post insulators, the metal fittings I and the metal fittings II, so that the single post insulator is prevented from being broken down by high voltage fluctuation during lightning stroke, the insulation and remediation capabilities of the four post insulators are enhanced, and the distribution transformer body is prevented from being directly damaged by high voltage.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lightning protection devices, in particular to a lightning protection device for a distribution transformer. BACKGROUND

[0002] With the development of economy, the reliability of urban distribution network is increasingly required, and the distribution transformer is an important equipment in the distribution network. If the lightning protection measures of the distribution transformer are not perfect, the transformer protection may be frequently tripped due to lightning. The transformer failure not only has a great impact on the reliability of the power grid, but also affects the production and living electricity of the people and the industry image of the power system, and directly affects the economic benefit of the power system.

[0003] At present, lightning protection devices are usually provided on the distribution transformer, but a large number of distribution transformers are damaged by lightning every year, and the damage is caused by many reasons.

[0004] For example, when lightning strikes, the slope of lightning is too steep, and single string insulator grounding is not enough to withstand the violent fluctuation of high voltage, which leads to the hidden danger of insulator flashover and breakdown, thereby losing insulation protection and directly damaging the distribution transformer. SUMMARY

[0005] (I) Technical problems solved

[0006] In view of the defects in the prior art, the present application provides a lightning protection device for a distribution transformer.

[0007] (II) Technical scheme

[0008] In order to achieve the above purpose, the present application provides the following technical scheme: a lightning protection device for a distribution transformer, comprising a distribution transformer body, wherein the distribution transformer body is provided with:

[0009] Two explosion-proof membrane plates are fixedly sleeved on the top and bottom of the outer wall of the distribution transformer body, respectively.

[0010] A lightning protection mechanism comprises:

[0011] Two column insulators are fixedly installed between the right sides of the two explosion-proof membrane plates in sequence.

[0012] Two gold utensils one are fixedly installed at the top end of the two column insulators, respectively.

[0013] The end of the two gold utensils one away from the column insulator is fixedly penetrated through the upper explosion-proof membrane plate and continues to extend upward.

[0014] Two gold utensils two are fixedly installed at the bottom end of the two column insulators, respectively.

[0015] The two fittings are fixed downwards at the ends furthest from the post insulator, penetrating the explosion-proof membrane plate below, and extending downwards further.

[0016] Two steel feet, the top ends of which are respectively fixedly connected to the downward extension ends of the two hardware fittings;

[0017] The copper busbar is fixedly fitted at both ends to the outer walls of the upward extension ends of the two hardware fittings.

[0018] There are two lightning protection mechanisms in total, with the other one symmetrically positioned between the left sides of the two explosion-proof membrane panels.

[0019] Preferably, the distribution transformer body is further provided with a low-voltage protection mechanism and a high-voltage protection mechanism, and the low-voltage protection mechanism includes:

[0020] There are four low-voltage terminals, which are fixedly installed sequentially on the top of the outer wall of the distribution transformer body;

[0021] There are eight connecting arms, and one end of each pair is fixedly sleeved on the top and bottom of each low-voltage terminal block;

[0022] There are two fixing plates, and their backs are respectively fixedly connected to the end of each of the four connecting arms that is away from the low-voltage terminal.

[0023] There are three disc-shaped insulators, which are fixedly installed between the two fixing plates in sequence;

[0024] There are two L-arms, each with one end fixedly connected to two disc-shaped insulators on either side. The disc-shaped insulators provide insulation against voltage creepage, protecting the low-voltage terminals.

[0025] Preferably, the other ends of the two L-arms are respectively fixedly connected to the outer walls of the upwardly extending ends of the fittings on both sides of the distribution transformer body. Electrical connectivity is ensured by using these fittings.

[0026] Preferably, the high-voltage protection mechanism includes:

[0027] There are three high-voltage terminals, which are fixedly installed sequentially on the top of the outer wall of the distribution transformer body, and located on the rear side of the top.

[0028] There are six connecting arms, and one end of each pair is fixedly sleeved on the top and bottom of each high-voltage terminal block;

[0029] There are three surge arresters, each fixedly installed between the two rear ends of the two connecting arms on each of the high-voltage terminals. The surge arresters guide the lightning pressure to the ground.

[0030] Preferably, a heat dissipation vent is provided on the front of the outer wall of the distribution transformer body. The heat dissipation vent is used to dissipate heat from inside the transformer.

[0031] Preferably, two mounting plates are fixedly installed sequentially on the bottom of the outer wall of the distribution transformer body, and the two mounting plates are symmetrically arranged. Each mounting plate has four mounting holes on its side wall. The distribution transformer can be conveniently installed on the power transmission line frame through the mounting plates.

[0032] Preferably, connecting fittings are fixedly installed on the bottom of the outer walls of the two mounting plates. A conductor's top end is fixedly connected to the bottom center of each connecting fitting, and an insulating rod is fixedly installed at the bottom end of the conductor. The insulating rod prevents the grounding grid voltage from flowing back along the conductor, thus avoiding voltage conflicts.

[0033] Preferably, the bottom ends of the two steel feet and the bottom end of the insulating rod are connected to a grounding grid. The voltage is diffused underground by setting up the grounding grid.

[0034] (III) Beneficial Effects

[0035] Compared with the prior art, the present invention provides a lightning protection device for distribution transformers, which has the following beneficial effects:

[0036] 1. This lightning protection device for distribution transformers uses four post insulators to guide high voltage to the ground along the steel feet through fittings one and two. This prevents high voltage fluctuations from breaking down a single post insulator during a lightning strike, thus avoiding loss of insulation protection. The four post insulators enhance insulation and remedial capabilities, preventing direct damage to the distribution transformer body from high voltage.

[0037] 2. This type of lightning protection device for distribution transformers uses the low voltage generated when the low voltage terminal is working to transmit the voltage along the L-arm to the fitting first through the creepage insulation of the disc insulator, and the residual voltage is guided to the grounding grid by the secondary insulation of the column insulator to disperse it, thereby protecting the distribution transformer body.

[0038] 3. This type of lightning protection device for distribution transformers prevents the high voltage that the high voltage terminal bears during operation from directly breaking down the high voltage terminal through the surge arrester, and guides the voltage from the distribution transformer body downward to the connecting hardware and along the conductor to the ground.

[0039] 4. This lightning protection device for distribution transformers allows overvoltage in the transformer body to flow to the ground along the connecting hardware and conductors, while the insulating rod blocks the backflow of residual voltage in the grounding grid, thus avoiding voltage conflicts. Attached Figure Description

[0040] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0041] Figure 1 This is a perspective view of the present invention;

[0042] Figure 2 This is a cross-sectional front view of the present invention;

[0043] Figure 3 This is a top view of the present invention;

[0044] Figure 4 This is a right-side cross-sectional view of the low-voltage protection mechanism of the present invention;

[0045] Figure 5 This is a right view of the high-voltage protection mechanism of the present invention;

[0046] Figure 6 This is a schematic diagram of the mounting plate of the present invention.

[0047] In the diagram: 1. Distribution transformer body; 2. Explosion-proof membrane; 3. Lightning protection mechanism; 301. Post insulator; 302. Fitting 1; 303. Fitting 2; 304. Steel foot; 305. Copper busbar; 4. Low-voltage protection mechanism; 401. Low-voltage terminal; 402. Connecting arm 1; 403. Fixing plate; 404. Disc insulator; 405. L-arm; 5. High-voltage protection mechanism; 501. High-voltage terminal; 502. Connecting arm 2; 503. Lightning arrester; 6. Heat sink; 7. Mounting plate; 8. Mounting hole; 9. Connecting fittings; 10. Conductor; 11. Insulating rod; 12. Grounding grid. Detailed Implementation

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0049] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0050] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0051] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0052] Example 1

[0053] like Figure 1 , 2 As shown in Figures 3 and 6, this invention provides a lightning protection device for a distribution transformer, including a distribution transformer body 1. The distribution transformer body 1 is provided with two explosion-proof membrane plates 2, which are respectively fixedly sleeved on the top and bottom of the outer wall of the distribution transformer body 1. The lightning protection mechanism 3 includes two column insulators 301, which are sequentially fixedly installed between the right sides of the two explosion-proof membrane plates 2. Two fittings 302 are respectively fixedly installed at the top of the two column insulators 301. The ends of the fittings 302 away from the column insulators 301 are fixedly inserted upwards through the explosion-proof membrane plates 2 above and continue to extend upwards. Two fittings 303 are respectively fixedly installed at the bottom of the two column insulators 301. Two fittings 303 are fixed downwards at the ends away from the column insulator 301, penetrating the explosion-proof membrane plate 2 below, and extending downwards. The tops of two steel feet 304 are fixedly connected to the downward extension ends of the two fittings 303 respectively. The two ends of the copper busbar 305 are fixedly sleeved on the outer walls of the upward extension ends of the two fittings 302 respectively. There are two lightning protection mechanisms 3 in total, and the other one is symmetrically arranged between the left sides of the two explosion-proof membrane plates 2. A heat dissipation vent 6 is opened on the front of the outer wall of the distribution transformer body 1. Two mounting plates 7 are fixedly installed in sequence at the bottom of the outer wall of the distribution transformer body 1, and the two mounting plates 7 are symmetrically arranged. Each mounting plate 7 has four mounting holes 8 on its side wall.

[0054] In this embodiment, the high voltage is guided to the ground along the steel foot 304 by four post insulators 301 through fittings 302 and 303, which avoids the high voltage fluctuations during lightning strikes from breaking down a single post insulator 301 and causing it to lose its insulation protection capability. The four post insulators 301 enhance the insulation and remedial capabilities, and prevent the high voltage from directly damaging the distribution transformer body 1.

[0055] Example 2

[0056] like Figure 1 , 2 As shown in Figures 3, 4, and 5, based on Embodiment 1, the present invention provides a technical solution: Preferably, the distribution transformer body 1 is further provided with a low-voltage protection mechanism 4 and a high-voltage protection mechanism 5, and the low-voltage protection mechanism 4 includes: four low-voltage terminals 401, which are fixedly installed on the top of the outer wall of the distribution transformer body 1 in sequence; eight connecting arms 402, with one end of each pair fixedly sleeved on the top and bottom of each low-voltage terminal 401; two fixing plates 403, with their back sides fixedly connected to the ends of each of the four connecting arms 402 away from the low-voltage terminals 401; three disc insulators 404, which are fixedly installed between the two fixing plates 403 in sequence; and two L-arms 405, with one end of each fixedly connected to the two disc insulators 404 on both sides, and the other ends of the two L-arms 405 fixedly connected to the outer wall of the upward extension end of the fittings 302 on both sides of the distribution transformer body 1.

[0057] In this embodiment, the low voltage generated when the low voltage terminal 401 is working is transmitted to the fitting 302 along the L arm 405 through the creepage insulation of the disc insulator 404, and the residual voltage is guided to the grounding grid 12 by the secondary insulation of the post insulator 301 to protect the distribution transformer body 1.

[0058] Example 3

[0059] like Figure 1 , 2 As shown in Figures 3, 5, and 6, based on Embodiment 1, the present invention provides a technical solution: Preferably, the high-voltage protection mechanism 5 includes three high-voltage terminals 501, which are sequentially and fixedly installed on the top of the outer wall of the distribution transformer body 1 and located on the rear side of the top; six connecting arms 502, with one end of each pair fixedly sleeved on the top and bottom of each high-voltage terminal 501; three surge arresters 503, which are respectively fixedly installed between the rear ends of the two connecting arms 502 on each high-voltage terminal 501; connecting hardware 9 is fixedly installed on the bottom of the outer wall of the two mounting plates 7; the top end of the conductor 10 is fixedly connected to the bottom middle of the connecting hardware 9; and an insulating rod 11 is fixedly installed on the bottom end of the conductor 10; and a grounding grid 12 is contacted and connected to the bottom end of the two steel feet 304 and the bottom end of the insulating rod 11.

[0060] In this embodiment, the high voltage that the high voltage terminal 501 bears during operation passes through the surge arrester 503 to prevent the high voltage from directly breaking down the high voltage terminal 501, and the voltage is guided downward from the distribution transformer body 1 to the connecting hardware 9 and along the conductor 10 to the ground.

[0061] The working principle of this type of lightning protection device for distribution transformers will be explained in detail below.

[0062] like Figures 1-6 As shown, in use, the mounting plate 7 is installed on the bottom of the transmission line frame by bolts through the mounting holes 8. The grounding grid 12 is buried underground, and the bottom ends of the insulating rod 11 and the steel foot 304 are connected to the grounding grid 12 by passing through the ground in sequence. The high-voltage terminal 501 and the low-voltage terminal 401 are respectively connected to the cable and the conductor. The connecting arm 402, the fixing plate 403, the L-arm 405, the fitting 302, and the copper busbar 305 form an electrically connected whole to ensure electrical connectivity. During a lightning strike, the lightning voltage fluctuation causes the high voltage to discharge through the high-voltage terminal 501 and the surge arrester 503, thus promoting... The voltage flows through the neutral point of the distribution transformer body 1 to the connecting hardware 9, and then flows into the ground along the conductor 10. The grounding current generates a voltage drop on the grounding resistance, which acts on the neutral point of the low-voltage side. The voltage is applied to the low-voltage winding, passes through the connecting arm 402 and the disc insulator 404 for creepage insulation, and is simultaneously guided along the L arm 405 to the hardware 302. The voltage is then applied to the two post insulators 301 through the copper busbar 305 for secondary insulation creepage. The residual voltage passes through the hardware 303 and along the steel foot 304 into the grounding grid 12 for diffusion.

[0063] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a reference structure" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A lightning protection device for a distribution transformer, comprising a distribution transformer body (1), characterized in that: The distribution transformer body (1) is equipped with: Two explosion-proof membrane plates (2) are respectively fixedly sleeved on the top and bottom of the outer wall of the power distribution transformer body (1); Lightning protection mechanism (3), including: Two post insulators (301) are fixedly installed between the right sides of the two explosion-proof membrane plates (2); Two fittings (302) are respectively fixedly installed on the top of the two column insulators (301); The two fittings (302) are fixed upward through the explosion-proof membrane plate (2) above the column insulator (301) at the ends away from the two fittings (302) and continue to extend upward. Two fittings (303) are respectively fixedly installed at the bottom ends of the two column insulators (301); The two fittings (303) are fixed downward through the explosion-proof membrane plate (2) below, and continue to extend downward at the ends away from the post insulator (301); Two steel feet (304) are fixedly connected at their top ends to the downward extension ends of the two hardware fittings (303); The copper busbar (305) is fixedly sleeved at both ends on the outer walls of the upward extension ends of the two hardware fittings (302); There are two lightning protection mechanisms (3), and the other one is symmetrically arranged between the left sides of the two explosion-proof membrane plates (2).

2. The lightning protection device for a distribution transformer according to claim 1, characterized in that: The distribution transformer body (1) is also provided with a low-voltage protection mechanism (4) and a high-voltage protection mechanism (5), and the low-voltage protection mechanism (4) includes: There are four low-voltage terminals (401), which are fixedly installed on the top of the outer wall of the distribution transformer body (1) in sequence; There are eight connecting arms (402), and one end of each pair is fixedly sleeved on the top and bottom of each low-voltage terminal (401); There are two fixing plates (403), and their back sides are respectively fixedly connected to the end of each of the four connecting arms (402) away from the low-voltage terminal (401); There are three disc insulators (404), which are fixedly installed between the two fixing plates (403) in sequence. The plane of the three disc insulators (404) is parallel to the plane of the two fixing plates (403). There are two L-arms (405), and one end of each arm is fixedly connected to the two disc insulators (404) on both sides.

3. The lightning protection device for a distribution transformer according to claim 2, characterized in that: The other ends of the two L-arms (405) are respectively fixedly connected to the outer wall of the upward extension end of the fittings (302) on both sides of the power distribution transformer body (1).

4. A lightning protection device for a distribution transformer according to claim 2, characterized in that: The high-voltage protection mechanism (5) includes: There are three high-voltage terminals (501), which are fixedly installed on the top of the outer wall of the distribution transformer body (1) in sequence and located on the rear side of the top. There are six connecting arms (502), and one end of each pair is fixedly sleeved on the top and bottom ends of each high-voltage terminal (501); There are three surge arresters (503), which are fixedly installed between the rear ends of the two connecting arms (502) on each of the high-voltage terminals (501).

5. A lightning protection device for a distribution transformer according to claim 1, characterized in that: The outer wall of the distribution transformer body (1) is provided with a heat dissipation vent (6).

6. A lightning protection device for a distribution transformer according to claim 1, characterized in that: Two mounting plates (7) are fixedly installed on the bottom of the outer wall of the power distribution transformer body (1) in sequence, and the two mounting plates (7) are symmetrically arranged. Each mounting plate (7) has four mounting holes (8) on its side wall.

7. A lightning protection device for a distribution transformer according to claim 6, characterized in that: Connecting fittings (9) are fixedly installed on the bottom of the outer walls of the two mounting plates (7). The top end of a conductor (10) is fixedly connected to the bottom middle of the connecting fittings (9), and an insulating rod (11) is fixedly installed at the bottom end of the conductor (10).

8. A lightning protection device for a distribution transformer according to claim 7, characterized in that: The bottom ends of the two steel feet (304) and the bottom end of the insulating rod (11) are connected to a grounding grid (12).

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