A method for grounding transformer core

Abstract

The present invention belongs to the technical field of transformer production and manufacturing, and in particular, relates to a new transformer core grounding method. The transformer core is composed of a core column, a lower iron yoke 1, a lower iron yoke 2, a side column 1 and a side column 2. A rectangular paint film removal area is respectively arranged on one side of the core column, the lower iron yoke 1, the lower iron yoke 2, the side column 1 and the side column 2. The five paint film removal areas are arranged in parallel in the horizontal direction. A copper strip is placed on the paint film removal area. One end of the copper strip is flush with the outer side of the side column 2. The other end of the copper strip extends out of the outer side of the side column 1. A grounding plate is placed on the upper surface of one end of the copper strip near the side column 1. The width of the grounding plate is greater than the width of the copper strip. The wiring terminal is fixedly connected to the grounding plate. The wiring terminal is crimped to one end of the grounding wire. The other end of the grounding wire is led to the box cover to connect the grounding sleeve. The copper strip of the present invention is assembled to run through the entire core paint removal range, so that the entire core silicon steel sheet has the same potential. The structure is simple, the operation is convenient, and the assembly is reliable and stable.

Description

Technical Field

[0001] The invention belongs to the technical field of transformer production and manufacturing, and in particular relates to a new transformer core grounding method. Background Art

[0002] During the operation of the transformer, the alternating magnetic field generates an alternating electric field, and the iron core in the electric field must be reliably grounded at one point. With the development of UHV power transmission technology, the capacity of a single transformer is getting larger and larger, and the diameter of the iron core is getting larger and larger. In order to ensure that the transformer core meets the temperature rise requirements, a number of oil channels need to be set inside the core for oil flow heat dissipation. The existing core grounding structure has the disadvantages of complex structure, cumbersome assembly, and poor reliability. Therefore, a new large-scale transformer core grounding structure and grounding method are needed, which can not only ensure that the core is reliably grounded at one point, but also have the advantages of simple structure, high degree of commonality, simple operation, and reliable and stable assembly. Summary of the invention

[0003] In view of the above technical problems, the present invention proposes a new large transformer core grounding method. The technical solution adopted by the present invention is:

[0004] A transformer core grounding method, the transformer core consists of a core column, a lower iron yoke 1, a lower iron yoke 2, a side column 1 and a side column 2, rectangular paint film removal areas are respectively arranged on one side of the core column, the lower iron yoke 1, the lower iron yoke 2, the side column 1 and the side column 2, the five paint film removal areas are arranged in parallel in the horizontal direction, a copper strip is placed on the paint film removal area, one end of the copper strip is flush with the outer side of the side column 2, and the other end of the copper strip extends out of the outer side of the side column 1, a grounding plate is placed on the upper surface of one end of the copper strip near the side column 1, the width of the grounding plate is greater than the width of the copper strip, a wiring terminal is fixedly connected to the grounding plate, the wiring terminal is crimped to one end of the grounding wire, and the other end of the grounding wire is led to a box cover to connect a grounding sleeve.

[0005] The beneficial effects of the present invention are:

[0006] (1) Through the unilateral removal of the paint film on the lower iron yoke, core column and side column of the main silicon steel sheet of the core, a copper strip is installed to penetrate the entire paint removal range of the core to make the entire core silicon steel sheet have the same potential.

[0007] (2) The grounding plate is assembled on the end of the copper strip, the wiring terminal is fastened to the grounding plate, and the wiring terminal is connected to the grounding wire and led to the box cover to connect the grounding sleeve and then grounded.

[0008] (3) Place the screws at the oil channel and make the silicon steel sheets on both sides of the oil channel have the same potential.

[0009] (4) Through the above assembly, the core silicon steel sheets become an equipotential body, and are led out to the grounding sleeve of the box cover through the grounding wire, thus realizing reliable grounding of the core at one point.

[0010] (5) The present invention has a simple structure, is easy to operate, and can be assembled reliably and stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a schematic structural diagram of a transformer core according to an embodiment of the present invention;

[0012] Figure 2 is a schematic structural diagram of a grounding plate according to an embodiment of the present invention;

[0013] Figure 3 is a front cross-sectional view of a terminal block according to an embodiment of the present invention;

[0014] Figure 4 is a schematic diagram of the assembly of a grounding component according to an embodiment of the present invention;

[0015] Figure 5 It is a schematic diagram of the assembly of the core oil channel of an embodiment of the present invention.

[0016] In the figure, 1 is the core column, 2 is the lower iron yoke 1, 3 is the lower iron yoke 2, 4 is the side column 1, 5 is the side column 2, 6 is the paint removal area, 7 is the threaded hole, 8 is the copper strip, 9 is the grounding plate, 10 is the terminal, 11 is the observation window, 12 is the iron core oil channel, and 13 is the screw. DETAILED DESCRIPTION

[0017] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar parts or parts having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0018] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, a mechanical connection or an electrical connection, a direct connection or an indirect connection through an intermediate medium, and 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.

[0019] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0020] like Figure 1As shown, it is a schematic diagram of the structure of the transformer core of an embodiment of the present invention. A transformer core grounding method, the transformer core is composed of a core column 1, a lower iron yoke 1 2, a lower iron yoke 2 3, a side column 1 4 and a side column 2 5, and rectangular paint film removal areas 6 are respectively arranged on one side of the core column 1, the lower iron yoke 1 2, the lower iron yoke 2 3, the side column 1 4 and the side column 2 5, and the five paint film removal areas 6 are arranged in parallel in the horizontal direction, and the paint film removal areas 6 are a certain distance away from the upper edge of the lower iron yoke, so that the copper strip 8 can completely cover the paint film removal areas 6. The copper strip 8 is a strip-shaped structure made of copper material, and the copper strip 8 is placed on the paint film removal area 6, one end of the copper strip 8 is flush with the outer side of the side column 2 5, and the other end of the copper strip 8 extends a certain distance from the outer side of the side column 1 4, and the copper strip 8 runs through all the paint film removal areas 6 of the entire transformer core to make the transformer core silicon steel sheets have equal potential.

[0021] A grounding sheet 9 is mounted on the upper surface of one end of the copper strip 8 near the side column 4, and the width of the grounding sheet 9 is slightly larger than the width of the copper strip 8. Figure 2 , which is a schematic diagram of the structure of the grounding plate according to an embodiment of the present invention. A hole is opened at the end of the grounding plate 9, and the hole is convenient for installing the wiring terminal 10.

[0022] like Figure 3 As shown, it is a front cross-sectional view of the wiring terminal of the embodiment of the present invention. One end of the wiring terminal 10 is a cavity structure, and the grounding wire is inserted into the cavity structure and crimped tightly. An observation window 11 is provided on the cavity structure, and a threaded hole 7 is provided at the end of the wiring terminal 10 away from the cavity structure. The observation window 11 is used to observe the crimping condition of the grounding wire and the wiring terminal 10. The wiring terminal 10 is made of a material with excellent conductive properties. The wiring terminal 10 is fixedly connected to the opening of the grounding plate 9 through the threaded hole 7 by fasteners such as bolts and nuts. The grounding wire is made of a material that is resistant to high temperature and transformer oil. The end of the grounding wire away from the wiring terminal 10 is led to the box cover and connected to the grounding sleeve, so that the transformer core can be reliably grounded at one point. As shown Figure 4 FIG. 1 is a schematic diagram of the assembly of the grounding component of an embodiment of the present invention.

[0023] Because the entire iron core is stacked up layer by layer of silicon steel sheets, a core fastening device is designed to ensure that the copper strip 8 and the grounding sheet 9 can be firmly and reliably installed and fixed without other fasteners.

[0024] As a further preferred embodiment, Figure 5 , which is a schematic diagram of the assembly of the core oil passage of an embodiment of the present invention. The core oil passage 12 is arranged in the core, which facilitates the heat dissipation of the core and prevents the core temperature from rising too high. The screw 13 is placed at the upper iron yoke end of the core oil passage 12, and the screw 13 makes the silicon steel sheets on both sides of the core oil passage 12 have the same potential.

[0025] The implementation cases of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the following description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A transformer core grounding method, wherein the transformer core is composed of a core column (1), a lower iron yoke 1 (2), a lower iron yoke 2 (3), a side column 1 (4) and a side column 2 (5), characterized in that: A rectangular paint removal area (6) is respectively arranged on one side of the core column (1), the lower iron yoke 1 (2), the lower iron yoke 2 (3), the side column 1 (4) and the side column 2 (5). The five paint removal areas (6) are arranged in parallel in the horizontal direction. A copper strip (8) is placed on the paint removal area (6). One end of the copper strip (8) is flush with the outer side of the side column 2 (5). The other end of the copper strip (8) extends out of the outer side of the side column 1 (4). A grounding plate (9) is placed on the upper surface of one end of the copper strip (8) close to the side column 1 (4). The width of the grounding plate (9) is greater than that of the copper strip (8). A wiring terminal (10) is fixedly connected to the grounding plate (9). The wiring terminal (10) is crimped to one end of the grounding wire. The other end of the grounding wire is led to the box cover to connect the grounding sleeve.

2. A transformer core grounding method according to claim 1, characterized in that: The iron core oil passage (12) is arranged in the iron core, and the screw (13) is placed at the end of the iron core oil passage (12) so that the iron cores on both sides of the oil passage have the same potential.

3. A transformer core grounding method according to claim 1, characterized in that: The copper belt (8) is a belt-shaped structure made of copper.

4. A transformer core grounding method according to claim 1, characterized in that: The end of the grounding plate (9) is provided with an opening, and the connection terminal (10) is fixedly connected to the opening of the grounding plate (9) by means of bolts and nuts.

5. A transformer core grounding method according to claim 1, characterized in that: One end of the connecting terminal (10) is a cavity structure, an observation window (11) is provided on the cavity structure, and a threaded hole (7) is provided at the end of the connecting terminal (10) away from the cavity structure.

6. A transformer core grounding method according to claim 1, characterized in that: The grounding wire is made of high temperature resistant and transformer oil resistant material.

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