Copper bar structure for connecting low voltage yn with high current

Abstract

The invention relates to a copper bar structure for connecting low voltage yn with high current. The copper bar structure comprises a first phase connecting assembly, a second phase connecting assembly, a third phase connecting assembly, a neutral point connecting assembly and a horizontal bar, the first phase connecting assembly, the second phase connecting assembly, the third phase connecting assembly and the neutral point connecting assembly are connected through a horizontal row, and the neutral point connecting assembly is arranged between the first phase connecting assembly and the second phase connecting assembly; the second phase connecting assembly comprises a second copper bar, a second phase coil, two second phase coil original lines and a U-shaped copper bar, the second copper bar is connected with one second phase coil original line, the second phase coil is arranged between the two second phase coil original lines, the other second phase coil original line is connected with the horizontal bar through the U-shaped copper bar, and the U-shaped copper bar is connected with the U-shaped copper bar. The second phase connecting assembly is connected with the horizontal row; the U-shaped copper bar is of a detachable structure and is used for adjusting the resistance value of the second phase connecting assembly. According to the technical scheme provided by the embodiment of the invention, the problems of relatively high resistor unbalance rate and relatively high material cost of an existing structure are solved.

Description

Technical Field

[0001] The invention relates to the technical field of power transformers, in particular to a low-voltage YN-connected high-current copper busbar structure. Background Art

[0002] As a device that converts electrical energy from one voltage to another, power transformers are indispensable in power systems. They play an important role in power distribution, load balancing, safety protection, and power quality regulation. Therefore, the stability of power transformers is a key factor in the stability and reliability of power supply. The three-phase resistance unbalance rate is one of the factors that affect the stability of power transformers. When the resistance unbalance rate exceeds the standard, it may cause a drop in rated power, excessive temperature rise inside the transformer, and increased noise. More seriously, it may cause a safety hazard and affect the normal operation of the power grid. According to the standard, the phase resistance unbalance rate of the power transformer (when there is a neutral point lead) should not be greater than 2%, and the line resistance unbalance rate (when there is no neutral point lead) should not be greater than 1%. However, due to the special structure of low-voltage Y-connected high-current power transformers, the resistance difference of the three-phase resistors is large and the resistance imbalance rate is high; the existing power transformers usually adopt the method of increasing the specifications of the neutral point copper bar to achieve the purpose of reducing the overall resistance difference, but the neutral point copper bar structure has the disadvantage of material waste. When the specifications of the neutral point copper bar are expanded, the resistance values ​​of the three-phase resistors will be affected. Usually, the specifications of the neutral point copper bar need to be expanded to more than 2 times to have a significant effect. The neutral point copper bar is long, which requires a large increase in material costs. Summary of the invention

[0003] (I) Purpose of the invention

[0004] The purpose of the present invention is to provide a low-voltage Y-connected high-current copper busbar structure, which changes the access position of the neutral point connection component and adds a U-shaped copper busbar to the second phase connection component to solve the problems of large resistance difference of the three-phase resistors, high resistance unbalance rate and high material cost of the existing low-voltage Y-connected high-current copper busbar structure.

[0005] (II) Technical solution

[0006] In order to solve the above problems, the present invention provides a low-voltage Y-connected high-current copper busbar structure, comprising a first phase connection component, a second phase connection component, a third phase connection component, a neutral point connection component and a horizontal bar;

[0007] The first phase connection component, the second phase connection component, the third phase connection component and the neutral point connection component are connected through the horizontal row, and the neutral point connection component is arranged between the first phase connection component and the second phase connection component;

[0008] The second phase connection component comprises a second copper bar, a second phase coil, two second phase coil primary wires and a U-shaped copper bar, wherein the second copper bar is connected to one of the second phase coil primary wires, the second phase coil is arranged between the two second phase coil primary wires, and the other second phase coil primary wire is connected to the horizontal bar through the U-shaped copper bar, so as to connect the second phase connection component to the horizontal bar;

[0009] The U-shaped copper busbar is a detachable structure and is used to adjust the resistance value of the second phase connection component.

[0010] The resistance values ​​of the first phase connection component, the second phase connection component and the third phase connection component are substantially equal.

[0011] The first phase connection component includes a first copper bar, a first phase coil and two first phase coil original wires, the first copper bar is connected to one of the first phase coil original wires, the first phase coil is arranged between the two first phase coil original wires, and the first phase connection component is connected to the horizontal bar through another first phase coil original wire.

[0012] The third phase connection component includes a third copper bar, a third phase coil and two third phase coil original wires, the third copper bar is connected to one of the third phase coil original wires, the third phase coil is arranged between the two third phase coil original wires, and the third phase connection component is connected to the horizontal bar through the other third phase coil original wire.

[0013] The neutral point connection assembly comprises a neutral point copper bar and a neutral point bushing, one end of the neutral point copper bar is connected to the neutral point bushing, and the other end of the neutral point copper bar is connected to the horizontal bar;

[0014] The neutral point copper bar is arranged between the first phase coil and the second phase coil.

[0015] The resistance values ​​of the first phase connection component, the second phase connection component and the third phase connection component are respectively:

[0016] R1=R 11 +R 12 +R 13

[0017] R2=R 21 +R 22 +R 23 +R 24

[0018] R3=R 31 +R 32 +R 33

[0019]

[0020] Where R1 represents the resistance of the first phase connection component, R 11 Indicates the resistance of the first copper bar, R 12 Represents the resistance of the first phase coil, R 13 represents the resistance of the first phase coil wire, R2 represents the resistance of the second phase connection component, R 21 Indicates the resistance of the second copper bar, R 22 Represents the resistance of the first phase coil, R 23 Indicates the resistance of the primary wire of the first phase coil, R 24 represents the resistance of the U-shaped copper busbar, R3 represents the resistance of the third phase connection component, R 31 Indicates the resistance of the third copper bar, R 32 Represents the resistance of the third phase coil, R 33 Indicates the resistance of the primary wire of the third phase coil, R 平 It represents the average resistance value of the first phase connection component, the second phase connection component and the third phase connection component.

[0021] Preferably, the U-shaped copper busbar is provided with a plurality of through holes, and the U-shaped copper busbar is connected to the horizontal busbar by fasteners through the through holes.

[0022] Preferably, the number of the through holes is related to the magnitude of the low-voltage phase current.

[0023] Preferably, the U-shaped copper busbar is connected to the other second-phase coil primary wire via a cold-pressed terminal.

[0024] (III) Beneficial effects

[0025] The above technical solution of the present invention has the following beneficial technical effects:

[0026] The present invention provides a low-voltage Y-connected high-current copper bar structure, comprising a first phase connection component, a second phase connection component, a third phase connection component, a neutral point connection component and a horizontal bar; the first phase connection component, the second phase connection component, the third phase connection component and the neutral point connection component are connected through the horizontal bar, and the neutral point connection component is arranged between the first phase connection component and the second phase connection component; the second phase connection component comprises a second copper bar, a second phase coil, two second phase coil original wires and a U-shaped copper bar, the second copper bar connects one of the second phase coil original wires, the second phase coil is arranged between the two second phase coil original wires, and the other second phase coil original wire is connected to the horizontal bar through the U-shaped copper bar, so as to connect the second phase connection component to the horizontal bar; the U-shaped copper bar is a detachable structure for adjusting the resistance value of the second phase connection component. The technical solution provided by the embodiment of the present invention effectively reduces the resistance unbalance rate by changing the access position of the neutral point component and adding a U-shaped copper bar with a certain resistance value in the second phase connection component, without enlarging the specification of the entire neutral point copper bar by more than 2 times, greatly reducing the use of the copper bar and reducing the material cost. By setting the U-shaped copper busbar as a detachable structure, when the actual resistance unbalance rate exceeds the standard, the U-shaped copper busbar can be easily replaced without removing the neutral point copper busbar, making the structure simpler and more convenient to install. The problem of large resistance difference, high resistance unbalance rate and high material cost of the existing low-voltage Y-connected high-current copper busbar structure of three-phase resistors is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0028] Figure 1 It is a schematic diagram of the overall structure of the low-voltage YN-connected high-current copper busbar structure of the present invention;

[0029] Figure 2 It is a wiring principle diagram of the low voltage YN connection high current copper busbar structure of the present invention;

[0030] Figure 3 It is a structural schematic diagram of a U-shaped copper busbar of a low-voltage Y-connected high-current copper busbar structure of the present invention;

[0031] Figure 4 It is a structural schematic diagram of a U-shaped copper busbar of a low-voltage Y-connected high-current copper busbar structure of the present invention;

[0032] Figure 5It is a schematic diagram of the unfolded structure of the U-shaped copper busbar of the low-voltage Y-connected high-current copper busbar structure of the present invention;

[0033] Reference numerals:

[0034] 1-first phase connection component; 11-first copper bar; 12-first phase coil; 13-first phase coil original wire; 2-second phase connection component; 21-second copper bar; 22-second phase coil; 23-second phase coil original wire; 24-U-shaped copper bar; 3-third phase connection component; 31-third copper bar; 32-third phase coil; 33-third phase coil original wire; 4-neutral point connection component; 41-neutral point copper bar; 42-neutral point bushing; 5-horizontal row. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the present invention.

[0036] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in one or more embodiments of the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in one or more embodiments of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0037] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings. The embodiment of the present invention provides a low-voltage Y-connected high-current copper busbar structure, Figure 1 This is the overall structural diagram of the low voltage YN-connected high current copper busbar structure. Figure 2 The wiring schematic diagram of the low voltage YN connected to the high current copper busbar structure is as follows: Figure 1-2 As shown, the structure includes: a first phase connection component 1, a second phase connection component 2, a third phase connection component 3, a neutral point connection component 4 and a horizontal row 5, the first phase connection component 1, the second phase connection component 2, the third phase connection component 3 and the neutral point connection component 4 are connected through the horizontal row 5, and the neutral point connection component 4 is arranged between the first phase connection component 1 and the second phase connection component 2;

[0038] Combination Figure 1 and Figure 2 The first phase connection component 1 includes a first copper bar 11, a first phase coil 12 and two first phase coil original wires 13. The first copper bar 11 is connected to one of the first phase coil original wires 13. The first phase coil 12 is arranged between the two first phase coil original wires 13. The first phase connection component 1 is connected to the horizontal row 5 through the other first phase coil original wire 13.

[0039] The second phase connection component 2 includes a second copper bar 21, a second phase coil 22, two second phase coil primary wires 23 and a U-shaped copper bar 24. The second copper bar 21 is connected to one of the second phase coil primary wires 23. The second phase coil 22 is arranged between the two second phase coil primary wires 23. The other second phase coil primary wire 23 is connected to the horizontal bar 5 through the U-shaped copper bar 24, so as to connect the second phase connection component 2 to the horizontal bar 5.

[0040] Preferably, the U-shaped copper busbar 24 is configured as a detachable structure for adjusting the resistance value of the second phase connection component 2. By configuring the U-shaped copper busbar 24 as a detachable structure, when the actual resistance imbalance rate exceeds the standard, the U-shaped copper busbar 24 can be conveniently replaced without removing the neutral point copper busbar 41, thereby making the structure simpler and more convenient to install.

[0041] Preferably, a plurality of through holes are provided on the U-shaped copper bar 24, and fasteners are used to connect the U-shaped copper bar 24 to the horizontal bar 5 through the through holes;

[0042] Preferably, the number of through holes is related to the magnitude of the low-voltage phase current.

[0043] In one embodiment,

[0044] like Figure 3-5 As shown, the U-shaped copper busbar 24 is processed by a piece of copper busbar. First, a hole is opened on the copper busbar, and then the copper busbar is bent to form a U-shaped copper busbar 24 with a certain bending angle.

[0045] The specifications and number of through holes of the copper busbar are determined by the low-voltage phase current;

[0046] Preferably, the copper busbar specification is based on the copper busbar current density less than 3.3A / mm 2 The commonly used copper busbar specifications are: 5×40, 5×50, 6×60, 8×80, 10×80, 10×100, etc.

[0047] Preferably, the number of through holes is selected, when the low-voltage phase current I is less than 2000A, the number of through holes is set to 4, when the low-voltage phase current I is less than 4000A, the number of through holes is set to 8, and so on.

[0048] In one embodiment, the diameter of the through hole is φ14, and the bending angle is R10.

[0049] Preferably, the U-shaped copper bar 24 is connected to another second phase coil original wire 23 via a cold pressing terminal;

[0050] Combination Figure 1 and Figure 2 The third phase connection component 3 includes a third copper bar 31, a third phase coil 32 and two third phase coil primary wires 33. The third copper bar 31 is connected to one of the third phase coil primary wires 33. The third phase coil 32 is arranged between the two third phase coil primary wires 33. The third phase connection component 3 is connected to the horizontal bar 5 through the other third phase coil primary wire 33.

[0051] The neutral point connection assembly 4 includes a neutral point copper bar 41 and a neutral point bushing 42, one end of the neutral point copper bar 41 is connected to the neutral point bushing 42, and the other end of the neutral point copper bar 41 is connected to the horizontal bar 5;

[0052] The neutral point copper bar 41 is disposed between the first phase coil 12 and the second phase coil 22 , and the neutral point copper bar 41 is located close to the second phase coil 22 .

[0053] By changing the access position of the neutral point copper bar 41 and accessing the U-shaped copper bar 24 in the second phase connection component 2, the resistance values ​​of the first phase connection component 1, the second phase connection component 2 and the third phase connection component 3 are substantially equal, which effectively reduces the resistance unbalance rate, and does not require the specification of the entire neutral point copper bar 41 to be enlarged by more than 2 times, which greatly reduces the use of the copper bar and reduces the material cost. The problem of large resistance difference, high resistance unbalance rate and high material cost of the existing low-voltage Y-type high-current copper bar structure of the three-phase resistor is solved.

[0054] Preferably, the resistance values ​​of the first phase connection component 1, the second phase connection component 2 and the third phase connection component 3 are respectively:

[0055] R1=R 11 +R 12 +R 13

[0056] R2=R 21 +R 22 +R 23 +R 24

[0057] R3=R 31 +R 32 +R 33

[0058]

[0059] Wherein, R1 represents the resistance value of the first phase connection component 1, R 11 Indicates the resistance of the first copper bar 11, R12 represents the resistance of the first phase coil 12, R 13 represents the resistance of the first phase coil wire 13, R2 represents the resistance of the second phase connection component 2, R 21 Indicates the resistance value of the second copper bus 21, R 22 represents the resistance of the first phase coil 22, R 23 Represents the resistance of the first phase coil primary wire 23, R 24 represents the resistance value of the U-shaped copper bus 24, R3 represents the resistance value of the third phase connection component 3, R 31 Indicates the resistance value of the third copper bus 31, R 32 represents the resistance value of the third phase coil 32, R 33 represents the resistance of the primary wire 33 of the third phase coil, R 平 It represents the average resistance value of the first phase connection component 1, the second phase connection component 2 and the third phase connection component 3.

[0060] In summary, the present invention relates to a low-voltage Y-connected high-current copper busbar structure, comprising a first phase connection component, a second phase connection component, a third phase connection component, a neutral point connection component and a horizontal bar; the first phase connection component, the second phase connection component, the third phase connection component and the neutral point connection component are connected through the horizontal bar, and the neutral point connection component is arranged between the first phase connection component and the second phase connection component; the second phase connection component comprises a second copper busbar, a second phase coil, two second phase coil original wires and a U-shaped copper busbar, the second copper busbar is connected to one of the second phase coil original wires, the second phase coil is arranged between the two second phase coil original wires, and the other second phase coil original wire is connected to the horizontal bar through the U-shaped copper busbar to connect the second phase connection component to the horizontal bar; the U-shaped copper busbar is a detachable structure for adjusting the resistance value of the second phase connection component. The technical solution provided by the embodiment of the present invention effectively reduces the resistance unbalance rate by changing the access position of the neutral point component and adding a U-shaped copper bar with a certain resistance value in the second phase connection component. It is not necessary to enlarge the specification of the entire neutral point copper bar by more than 2 times, which greatly reduces the use of the copper bar and reduces the material cost. By setting the U-shaped copper bar as a detachable structure, when the actual resistance unbalance rate exceeds the standard, the U-shaped copper bar can be easily replaced without disassembling the neutral point copper bar, making the structure of the structure simpler and more convenient to install. The problem of large resistance difference, high resistance unbalance rate and high material cost of the existing low-voltage Y-type high-current copper bar structure of the three-phase resistor is solved.

[0061] It should be understood that the above specific embodiments of the present invention are only used to illustrate or explain the principles of the present invention, and do not constitute a limitation of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modifications that fall within the scope and boundaries of the appended claims, or the equivalent forms of such scope and boundaries.

Claims

1. A low voltage YN connection high current copper busbar structure, characterized in that: It comprises a first phase connection component (1), a second phase connection component (2), a third phase connection component (3), a neutral point connection component (4) and a horizontal row (5); The first phase connection component (1), the second phase connection component (2), the third phase connection component (3) and the neutral point connection component (4) are connected via the horizontal row (5), and the neutral point connection component (4) is arranged between the first phase connection component (1) and the second phase connection component (2); The second phase connection component (2) comprises a second copper bar (21), a second phase coil (22), two second phase coil primary wires (23) and a U-shaped copper bar (24); the second copper bar (21) is connected to one of the second phase coil primary wires (23); the second phase coil (22) is arranged between the two second phase coil primary wires (23); the other second phase coil primary wire (23) is connected to the horizontal bar (5) via the U-shaped copper bar (24), so as to connect the second phase connection component (2) to the horizontal bar (5); The U-shaped copper busbar (24) is a detachable structure and is used to adjust the resistance value of the second phase connection component (2).

2. The structure according to claim 1, characterized in that: The resistance values ​​of the first phase connection component (1), the second phase connection component (2) and the third phase connection component (3) are substantially equal.

3. The structure according to claim 2, characterized in that: The first phase connection component (1) comprises a first copper bar (11), a first phase coil (12) and two first phase coil primary wires (13); the first copper bar (11) is connected to one of the first phase coil primary wires (13); the first phase coil (12) is arranged between the two first phase coil primary wires (13); and the first phase connection component (1) is connected to the horizontal bar (5) via the other first phase coil primary wire (13).

4. The structure according to claim 3, characterized in that: The third phase connection component (3) comprises a third copper bar (31), a third phase coil (32) and two third phase coil primary wires (33); the third copper bar (31) is connected to one of the third phase coil primary wires (33); the third phase coil (32) is arranged between the two third phase coil primary wires (33); and the third phase connection component (3) is connected to the horizontal bar (5) via the other third phase coil primary wire (33).

5. The structure according to claim 4, characterized in that: The neutral point connection assembly (4) comprises a neutral point copper bar (41) and a neutral point bushing (42), one end of the neutral point copper bar (41) is connected to the neutral point bushing (42), and the other end of the neutral point copper bar (41) is connected to the horizontal bar (5); The neutral point copper bar (41) is arranged between the first phase coil (12) and the second phase coil (22).

6. The structure according to claim 5, characterized in that The resistance values ​​of the first phase connection component (1), the second phase connection component (2) and the third phase connection component (3) are respectively: R1=R 11 +R 12 +R 13 R2=R 21 +R 22 +R 23 +R 24 R3=R 31 +R 32 +R 33 Wherein, R1 represents the resistance value of the first phase connection component (1), R 11 represents the resistance of the first copper bar (11), R 12 represents the resistance of the first phase coil (12), R 13 represents the resistance value of the first phase coil primary wire (13), R2 represents the resistance value of the second phase connecting component (2), R 21 represents the resistance value of the second copper bar (21), R 22 represents the resistance of the first phase coil (22), R 23 represents the resistance of the primary wire (23) of the first phase coil, R 24 represents the resistance value of the U-shaped copper busbar (24), R3 represents the resistance value of the third phase connection component (3), R 31 represents the resistance value of the third copper bar (31), R 32 represents the resistance of the third phase coil (32), R 33 represents the resistance of the primary wire (33) of the third phase coil, R 平 Table 2 shows the average resistance values ​​of the first phase connection component (1), the second phase connection component (2) and the third phase connection component (3).

7. The structure according to claim 1, characterized in that The U-shaped copper busbar (24) is provided with a plurality of through holes, and the U-shaped copper busbar (24) is connected to the horizontal busbar (5) by fasteners through the through holes.

8. The structure according to claim 7, characterized in that The number of the through holes is related to the magnitude of the low-voltage phase current.

9. The structure according to claim 1, characterized in that The U-shaped copper bar (24) is connected to the other second-phase coil primary wire (23) via a cold-pressed terminal.

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