Low-voltage copper bar structure of transformer

Abstract

The low-voltage copper bar structure comprises a c-phase line, a b-phase line and an a-phase line which are led out from the top end of the transformer, and is characterized by further comprising an o-phase line, a first-stage copper bar and a second-stage copper bar, the tail ends of the c-phase line, the b-phase line and the a-phase line are electrically connected with the first-stage copper bar respectively, and the connection points are a Z point, a Y point and an X point respectively; two ends of the second-stage copper bar are respectively connected with a tail end Z point of the c-phase line and a tail end X point of the a-phase line, and the first-stage copper bar and the second-stage copper bar are arranged in parallel; the tail end of the o-phase line is connected with the second-stage copper bar, and the connection point is a point P. The point P of the connection point of the tail end of the o-phase line and the second-stage copper bar is located at the intersection point where the b-phase line axially extends to the bridging copper bar.

Description

Technical Field

[0001] This utility model relates to the technical field of transformers, and in particular to a low-voltage copper busbar structure for a transformer. Background Technology

[0002] When conventional transformer products (power transformers and special transformers with specific capacity ranges) use a star connection for low voltage, if the ratio of the length of the low voltage lead to the length of the conductor used in the low voltage coil is large, and the low voltage lead is mostly connected using copper busbars, then the DC resistance deviation between the three phases is difficult to meet the national standard requirements (capacity > 1600kVA; line-to-line deviation ≤ 1%; phase-to-phase deviation ≤ 2%). This requirement and test are among the mandatory items for transformer products before shipment. The difficulty in solving this problem lies in the fact that for some transformers with specific capacity ranges (power transformers or special transformers), the proportion of the low voltage lead length to the low voltage coil conductor length is large, and the cross-sectional area of ​​both the low voltage lead and the low voltage coil conductor is also large, resulting in a relatively low DC resistance. This results in higher DC resistance in phases A and C, and lower DC resistance in phase B. Therefore, the structure and manufacturing process of the low voltage lead have a significant impact on the DC resistance of the product, which is one of the frequently encountered and difficult-to-solve technological problems in the industry.

[0003] Therefore, based on the above-mentioned technical problems, this application proposes a low-voltage copper busbar structure for a transformer that is structurally reasonable, has a high yield rate, and is safe and reliable. Summary of the Invention

[0004] The purpose of this utility model is to overcome the shortcomings of the existing technology and provide a low-voltage copper busbar structure for a transformer that is structurally reasonable, has a high yield rate, and is safe and reliable.

[0005] To achieve the above objectives, this utility model provides a low-voltage copper busbar structure for a transformer, comprising a c-phase line, a b-phase line, and an a-phase line extending from the top of the transformer. Its features include: an o-phase line, a primary copper busbar, and a secondary copper busbar. The tail ends of the c-phase line, b-phase line, and a-phase line are electrically connected to the primary copper busbar at points Z, Y, and X, respectively. The two ends of the secondary copper busbar are connected to the tail end of the c-phase line at point Z and the tail end of the a-phase line at point X, respectively. The primary and secondary copper busbars are connected in parallel. The tail end of the o-phase line is connected to the secondary copper busbar at point P, where point P is located at the intersection of the b-phase line extending axially to the bridging copper busbar.

[0006] Furthermore, the cross-sectional area of ​​the secondary copper busbar is two-thirds of the cross-sectional area of ​​the primary copper busbar.

[0007] Furthermore, the c-phase line, b-phase line, a-phase line and the primary copper busbar are respectively connected by bolts, and the c-phase line, a-phase line and the secondary copper busbar are respectively connected by bolts.

[0008] The present invention adopts the above-mentioned solution, and its beneficial effects are as follows: the design of the copper busbar in the transformer is optimized, the current carrying capacity and overload capacity of the copper busbar are increased, the service life of the transformer is extended, and the product yield is improved and the production cost is reduced. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the low-voltage copper busbar structure in this embodiment.

[0010] Figure 2 for Figure 1 A schematic diagram of the cross-section at point AA.

[0011] Among them, 1-c phase line, 11-Z point, 2-b phase line, 21-Y point, 3-a phase line, 31-X point, 4-o phase line, 41-P point, 5-first-level copper busbar, and 6-second-level copper busbar. Detailed Implementation

[0012] To facilitate understanding of this utility model, a more complete description of it is provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the utility model. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to provide a more thorough and complete understanding of the disclosure of this utility model.

[0013] See appendix Figure 1 As shown in this embodiment, a low-voltage copper busbar structure of a transformer includes a c-phase line 1, a b-phase line 2, and an a-phase line 3 led out from the top of the transformer. The characteristic is that it also includes an o-phase line 4, a primary copper busbar 5, and a secondary copper busbar 6. It should be noted that the first end of the c-phase line 1, b-phase line 2, and a-phase line 3 is the high-voltage output end (the last end is the low-voltage output end). The structure is a conventional design and no specific restrictions are imposed here.

[0014] See appendix Figure 1 , 2 As shown, in this embodiment, the tail ends of phase c 1, phase b 2 and phase a 3 are electrically connected to the primary copper busbar 5, and the connection points are Z point 11, Y point 21 and X point 31, respectively. The two ends of the secondary copper busbar 6 are connected to the tail end Z point 11 of phase c 1 and the tail end X point 31 of phase a 3, respectively. The primary copper busbar 5 and the secondary copper busbar 6 are connected in parallel. The tail end of phase o 4 is connected to the secondary copper busbar 6, and the connection point is P point 41. The connection point P point 41 between the tail end of phase o 4 and the secondary copper busbar 6 is located at the intersection of phase b 2 extending axially to the bridging copper busbar.

[0015] In this embodiment, the cross-sectional area of ​​the secondary copper busbar 6 is two-thirds of the cross-sectional area of ​​the primary copper busbar 5. Specifically, the height and thickness of the primary copper busbar 5 and the secondary copper busbar 6 can be modified according to actual production requirements. No specific restrictions are imposed here, but it is necessary to ensure that the two are in the above-mentioned multiple relationship. By increasing the cross-sectional area of ​​the copper busbar, the purpose of balancing the DC resistance of the windings in the transformer can be achieved under high current.

[0016] In this embodiment, phase c 1, phase b 2, and phase a 3 are connected to the primary copper busbar 5 and phase c 1 and phase a 3 are connected to the secondary copper busbar 6, respectively, by bolts. This saves assembly time, improves production efficiency, and makes it easier to enhance the connection tightness of the transformer and adjust the connection between structural components.

[0017] The embodiments described above are merely preferred embodiments of this utility model and are not intended to limit the utility model in any way. Any modifications or alterations made by those skilled in the art to the technical solution of this utility model without departing from its scope are equivalent embodiments of this utility model. Therefore, all equivalent changes made based on the concept of this utility model without departing from its scope should be covered within the protection scope of this utility model.

Claims

1. A low-voltage copper busbar structure for a transformer, comprising a c-phase line (1), a b-phase line (2), and an a-phase line (3) extending from the top of the transformer, characterized in that: It also includes an o-phase line (4), a primary copper busbar (5), and a secondary copper busbar (6). The tail ends of the c-phase line (1), b-phase line (2), and a-phase line (3) are electrically connected to the primary copper busbar (5) and the connection points are Z point (11), Y point (21), and X point (31), respectively. The two ends of the secondary copper busbar (6) are connected to the tail end Z point (11) of the c-phase line (1) and the tail end X point (31) of the a-phase line (3), respectively. The primary copper busbar (5) and the secondary copper busbar (6) are connected in parallel. The tail end of the o-phase line (4) is connected to the secondary copper busbar (6) and the connection point is P point (41). The connection point P point (41) between the tail end of the o-phase line (4) and the secondary copper busbar (6) is located at the intersection of the b-phase line (2) extending axially to the bridging copper busbar.

2. The low-voltage copper busbar structure of a transformer according to claim 1, characterized in that: The cross-sectional area of ​​the secondary copper busbar (6) is two-thirds of the cross-sectional area of ​​the primary copper busbar (5).

3. The low-voltage copper busbar structure of a transformer according to claim 1, characterized in that: The c-phase line (1), b-phase line (2), a-phase line (3) are connected to the primary copper busbar (5) and the c-phase line (1), a-phase line (3) are connected to the secondary copper busbar (6) respectively with bolts.

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