CN211929280U

CN211929280U - Power transformer

Info

Publication number: CN211929280U
Application number: CN202020958547.3U
Authority: CN
Inventors: 侯丽丽; 王桂平; 付大金; 杨智强; 李雷; 孙晓林; 周剑
Original assignee: Siemens Transformer Jinan Co Ltd
Current assignee: Siemens Transformer Jinan Co Ltd
Priority date: 2020-05-29
Filing date: 2020-05-29
Publication date: 2020-11-13
Anticipated expiration: 2030-05-29

Abstract

The utility model provides a power transformer, including vary voltage subassembly and tapping switch (50). The transformer assembly comprises a core column (10), a primary side coil (20), a voltage regulating coil (30) and a secondary side coil (40). The secondary side coil, the primary side coil and the voltage regulating coil surround the core column and are arranged along the radial direction of the core column. The primary coil comprises two parallel primary coil segments (21). The primary side coil section comprises two primary side coil subsections (23). The voltage regulating coil comprises two voltage regulating coil sections (31). The voltage regulating coil sections are in one-to-one correspondence with the primary side coil sections. Each voltage regulating coil segment has a plurality of tap taps (312). The tap switch is connected with each tap and each primary side coil subsection. The tap switch is operable to serially connect different portions of each voltage regulating coil section between two primary coil subsections of the primary coil section corresponding thereto, or to directly serially connect two primary coil subsections of each primary coil section. The insulation cost of the power transformer is low.

Description

Power transformer

Technical Field

The utility model relates to a power transformer, especially a lower power transformer of insulation cost.

Background

At present, in a power transformer adopting a middle outgoing line mode for leading heads of primary coils, upper and lower primary coil sections of the primary coils are connected in parallel, correspondingly, voltage regulating coils are also made to be connected in parallel, and then the primary coils are connected with the voltage regulating coils in series. When the three-phase primary side coil adopts a triangular connection method, the voltage regulating coil is equivalently connected at the wire end position of the primary side coil, the requirements on the insulation level of the voltage regulating coil and the insulation level of a switch for controlling the tapping of the voltage regulating coil are high, and the insulation cost is increased.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a power transformer, its insulation cost is lower.

The utility model provides a power transformer, it includes a vary voltage subassembly and a tapping switch. The voltage transformation assembly comprises a core column, a primary side coil, a voltage regulation coil and a secondary side coil. The secondary side coil, the primary side coil and the voltage regulating coil surround the core column and are arranged along the radial direction of the core column. The primary side coil comprises two primary side coil sections which are arranged in parallel along the axial direction of the core column. Each primary side coil section comprises two primary side coil subsections which are arranged along the axial direction of the core column. The voltage regulating coil comprises two voltage regulating coil sections which are arranged along the axial direction of the core column. The two voltage regulating coil sections are arranged in one-to-one correspondence with the two primary side coil sections. Each voltage regulating coil segment has a plurality of tap taps. The tap switch is connected with a plurality of tap taps of each voltage regulating coil section and two primary side coil subsections of each primary side coil section. The tap switch is operable to serially connect different portions of each voltage regulating coil section between two primary coil subsections of the primary coil section corresponding thereto, or to directly serially connect two primary coil subsections of each primary coil section.

The insulation cost of the power transformer is low.

In another exemplary embodiment of the power transformer, the secondary side coil, the primary side coil and the voltage regulating coil are arranged in order from the inside to the outside in a radial direction of the core column. This arrangement is advantageous in reducing eddy currents and reducing heat generation.

In a further exemplary embodiment of the power transformer, the two primary coil sub-sections of each primary coil section have two ends which are close to one another in the axial direction of the limb and have an outlet for connection to a tap changer. This is advantageous for reducing the requirements on the insulation level of the voltage regulating coil and the tap changer.

In a further exemplary embodiment of the power transformer, each voltage regulating coil section comprises two voltage regulating coil subsections arranged in series and arranged along the axial direction of the core limb. And a gap is reserved between the two voltage regulating coil subsections of each voltage regulating coil section in the axial direction of the core column. The outlet of the two primary side coil subsections of each primary side coil section, which is used for connecting the tap switch, penetrates out from the gap between the two voltage regulating coil subsections of the voltage regulating coil section corresponding to the outlet. Thereby facilitating the reduction of the diameter of the voltage regulating coil.

In a further exemplary embodiment of the power transformer, the first-end outlet of the primary winding is in a middle outlet mode and the first-end outlet passes through between the two voltage-regulating winding sections. Thereby facilitating a reduction in yoke insulation size.

In yet another exemplary embodiment of the power transformer, the primary winding is wound in a pancake type, and the voltage regulating winding is wound in a layer type. The winding mode of the primary side coil is a cake type, which is beneficial to improving the insulation performance. The winding mode of the voltage regulating coil is a layer type, so that the wiring is convenient.

In yet another exemplary embodiment of the power transformer, the voltage transformation assembly is provided with two secondary side coils. The two secondary side coils are arranged along the axial direction of the core column.

In a further exemplary embodiment of the power transformer, the power transformer is a three-phase power transformer, which is provided with three transforming assemblies and three tap changers. The primary side coils of the three voltage transformation components are connected in a triangular mode. The secondary side coils of the three voltage transformation components are connected in a star connection mode. The three tap switches are respectively connected with the three voltage transformation components. The adoption of three tap changers is beneficial to improving the safety performance.

Drawings

The following drawings are only schematic illustrations and explanations of the present invention, and do not limit the scope of the present invention.

Fig. 1 is a schematic structural diagram of an exemplary embodiment of a power transformer.

Fig. 2 is a schematic structural diagram of another exemplary embodiment of a power transformer.

Description of the reference symbols

10 core column

20 primary side coil

21 primary side coil segment

23 primary side coil subsection

30 voltage regulating coil

31 voltage regulating coil section

33 voltage regulating coil subsegment

312 tap

Gap between 32 voltage regulating coil subsections

40 secondary side coil

50-tap switch

Axial direction of L-shaped core column

Detailed Description

In order to clearly understand the technical features, objects, and effects of the present invention, embodiments of the present invention will be described with reference to the accompanying drawings, wherein the same reference numerals in the drawings denote the same or similar components.

"exemplary" means "serving as an example, instance, or illustration" herein, and any illustration, embodiment, or steps described as "exemplary" herein should not be construed as a preferred or advantageous alternative.

For the sake of simplicity, only the parts relevant to the present invention are schematically shown in the drawings, and they do not represent the actual structure as a product.

Fig. 1 is a schematic structural diagram of an exemplary embodiment of a power transformer. As shown in fig. 1, the power transformer includes a transformer assembly and a tap changer 50. The transformer assembly includes a core 10, a primary winding 20, a voltage regulating winding 30 and two secondary windings 40. The secondary side coil 40, the primary side coil 20, and the voltage-regulating coil 30 are all wound around the stem 10. The two secondary side coils 40 are aligned in the axial direction L of the core column 10. The secondary side coil 40, the primary side coil 20 and the voltage regulating coil 30 are sequentially arranged from inside to outside along the radial direction of the core column 10, and the arrangement mode is favorable for reducing eddy current and reducing heat generation.

The primary-side coil 20 includes two primary-side coil segments 21 arranged in parallel in the axial direction L of the core column 10. Each primary-side coil segment 21 includes two primary-side coil subsections 23 arranged in the axial direction L of the core column 10. The voltage regulating coil 30 includes two voltage regulating coil sections 31 arranged along the axial direction L of the stem 10. The two voltage regulating coil segments 31 are arranged in one-to-one correspondence with the two primary coil segments 21, i.e., one voltage regulating coil segment 31 is correspondingly arranged for one primary coil segment 21. In the present exemplary embodiment, the head end lead-out of the primary side coil 20 adopts a middle lead-out manner and the head end lead-out passes between the two voltage regulating coil sections 31, thereby facilitating the reduction of the yoke insulation size, but is not limited thereto. Each of the voltage regulator coil segments 31 has a number of tap taps 312 corresponding to different portions of the voltage regulator coil segment 31.

The tap switch 50 connects the plurality of tap taps 312 of each voltage regulating coil segment 31 and the two primary coil subsections 23 of each primary coil segment 21. The tap changer 50 is operable to serially connect different portions of each voltage regulating coil section 31 between the two primary coil sections 23 of the primary coil section 21 corresponding thereto, or to directly serially connect the two primary coil sections 23 of each primary coil section 21, thereby achieving a regulating function.

In the power transformer, the two primary side coil subsections 23 of each primary side coil section 21 are in series connection, and the corresponding voltage regulating coil section 31 can be connected in series between the two primary side coil subsections 23, so that the requirement on the insulation level of the voltage regulating coil and the tap switch can be reduced, and the insulation cost is reduced.

In the exemplary embodiment, the two primary coil subsections 23 of each primary coil section 21 are tapped at two ends that are close to each other in the axial direction L of the core limb 10 for connection to the tap changer 50. This is advantageous for reducing the requirements on the insulation level of the voltage regulating coil and the tap changer.

In the exemplary embodiment, the primary side coil 20 is wound in a pie shape to improve the insulation performance. The voltage regulating coil 30 is wound in a layer type to facilitate wiring.

Fig. 2 is a schematic structural diagram of another exemplary embodiment of a power transformer. The power transformer of the exemplary embodiment is the same as or similar to the power transformer shown in fig. 1, and the differences are as follows. As shown in fig. 2, in the present exemplary embodiment, each voltage regulating coil section 31 includes two voltage regulating coil subsections 33 arranged in series along the axial direction L of the core column 10. A gap 32 is left between the two voltage regulating coil subsections 33 of each voltage regulating coil section 31 in the axial direction L of the stem 10. The outlets of the two primary coil subsections 23 of each primary coil section 21 for connecting the tap switch 50 are led out from the gap 32 between the two voltage regulating coil subsections 33 of the voltage regulating coil section 31 corresponding thereto. Thereby facilitating the reduction of the diameter of the voltage regulating coil.

In yet another exemplary embodiment of the power transformer, the power transformer is a three-phase power transformer provided with three transformation assemblies as shown in fig. 2 and three tap changers 50 as shown in fig. 2. The primary side coils 20 of the three voltage transformation components are connected in a delta connection mode. The secondary side coils 40 of the three voltage transformation assemblies are connected in a star connection mode. The three tap changers 50 are respectively connected with three voltage transformation components, and the connection relationship is as shown in fig. 2. The use of three tap changers 50 facilitates improved safety. Without limitation, in other exemplary embodiments, only one tap changer 50 may be provided, with three voltage transformation assemblies sharing a tap changer 50.

It should be understood that although the present description has been described in terms of various embodiments, not every embodiment includes only a single embodiment, and such description is for clarity purposes only, and those skilled in the art will recognize that the embodiments described herein may be combined as suitable to form other embodiments, as will be appreciated by those skilled in the art.

The above list of details is only for the practical examples of the present invention, and they are not intended to limit the scope of the present invention, and all equivalent embodiments or modifications, such as combinations, divisions or repetitions of the features, which do not depart from the technical spirit of the present invention, should be included in the scope of the present invention.

Claims

1. A power transformer, comprising:

a voltage transformation assembly, comprising:

a stem (10) of the device,

a primary side coil (20) surrounding the core leg (10); the primary side coil (20) comprises two primary side coil segments (21) which are arranged in parallel along the axial direction (L) of the core column (10); each primary coil section (21) comprises two primary coil subsections (23) arranged along the axial direction (L) of the core column (10),

a voltage regulating coil (30) surrounding said stem (10); the voltage regulating coil (30) comprises two voltage regulating coil sections (31) which are arranged along the axial direction (L) of the core column (10); the two voltage regulating coil sections (31) are arranged in one-to-one correspondence with the two primary side coil sections (21); each of the voltage regulating coil segments (31) has a plurality of tap-offs (312), an

A secondary side coil (40) surrounding said core leg (10); the secondary side coil (40), the primary side coil (20) and the voltage regulating coil (30) are arranged along the radial direction of the core column (10); and

a tap changer (50) connecting said plurality of tap taps (312) of each of said voltage regulating coil segments (31) and said two primary coil subsections (23) of each of said primary coil segments (21); the tap changer (50) is operable to serially connect different portions of each of the voltage regulating coil segments (31) between the two primary coil sub-segments (23) of the primary coil segment (21) corresponding thereto, or to directly serially connect the two primary coil sub-segments (23) of each of the primary coil segments (21).

2. A power transformer according to claim 1, characterized in that said secondary side coil (40), said primary side coil (20) and said voltage regulating coil (30) are arranged in sequence from inside to outside in the radial direction of said core leg (10).

3. A power transformer according to claim 2, characterized in that the two primary side coil sub-sections (23) of each primary side coil section (21) have outlets at their ends which are close to each other in the axial direction (L) of the core limb (10) for connection to the tap changer (50).

4. A power transformer according to claim 3, characterized in that each of said voltage regulating coil segments (31) comprises two voltage regulating coil subsections (33) arranged in series and aligned in the axial direction (L) of said core leg (10); a gap (32) is reserved between the two voltage regulating coil subsections (33) of each voltage regulating coil section (31) in the axial direction (L) of the core column (10); the outlet of the two primary coil subsections (23) of each primary coil section (21) for connecting the tap switch (50) penetrates out of a gap (32) between the two voltage regulating coil subsections (33) of the voltage regulating coil section (31) corresponding to the outlet.

5. A power transformer according to claim 1, characterized in that the head end outlet of the primary winding (20) is in a middle outlet mode and the head end outlet passes between the two voltage regulating winding sections (31).

6. A power transformer according to claim 1, characterized in that the primary winding (20) is wound in a pancake manner; the voltage regulating coil (30) is wound in a layered mode.

7. A power transformer according to claim 1, characterized in that said transforming assembly is provided with two said secondary side coils (40); the two secondary side coils (40) are arranged in the axial direction (L) of the core column (10).

8. An electric transformer according to claim 1, characterized in that said electric transformer is a three-phase electric transformer provided with three said transforming assemblies and three said tap changers (50); the primary side coils (20) of the three voltage transformation components are connected in a triangular mode; the secondary side coils (40) of the three voltage transformation components are connected in a star connection mode; the three tap changers (50) are respectively connected with the three voltage transformation components.