A single-machine 48-pulse rectifier transformer
By setting a specific structure and winding arrangement within the rectifier transformer, a single-unit 48-pulse rectifier transformer was developed, solving the problem that existing rectifier transformers cannot meet the needs of large-capacity applications. This achieved efficient harmonic suppression and improved the power quality of the power grid.
Patent Information
- Application Number
- CN202211517969.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-11-29
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2042-11-29
AI Technical Summary
Existing multi-pulse output rectifier transformers cannot meet the needs of large-capacity use, resulting in harmonic pollution of the power grid and reducing the power quality of the power grid.
Design a single-unit 48-pulse rectifier transformer. By setting two sets of voltage regulating transformer bodies and two sets of rectifier transformer bodies in the oil tank, two equivalent 24-pulse output systems are formed respectively. Combined with a specific winding arrangement and core structure, a single-unit equivalent 48-pulse output is achieved.
This significantly reduces the harmonic content fed back to the power grid from the rectifier transformer, thus improving the power quality of the power grid.
Smart Images
Figure CN115763014B_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of transformers, and particularly relates to a single-unit forty-eight-pulse rectifier transformer. Background Art
[0002] A rectifier transformer is a power device that provides power for rectifier equipment. Rectifier equipment has a very wide range of applications in industrial production such as metallurgy, chemical industry, hydrogen production, etc.
[0003] A large number of non-linear load components such as thyristors are used in rectifier equipment. During the operation process, these non-linear load components will inevitably generate a large amount of harmonics. The harmonics are fed back to the power grid through the rectifier transformer, which will cause serious pollution to the power grid and reduce the power quality of the power grid. To improve this situation, a multi-pulse design is carried out on the rectifier transformer to cancel out a certain number of harmonics in the rectifier transformer and reduce the harmonic content fed back to the power grid by the rectifier transformer.
[0004] With the continuous increase of the capacity of rectifier transformers, the demand for rectifier transformers with multi-pulse output is increasing. The existing pulse rectifier transformers are increasingly unable to meet the usage requirements, resulting in more harmonics entering the power grid, polluting the power grid, and reducing the power quality of the power grid. Summary of the Invention
[0005] The purpose of the present invention is to provide a single-unit forty-eight-pulse rectifier transformer, aiming to solve the problem that the existing rectifier transformers with multi-pulse output cannot meet the usage requirements.
[0006] To achieve the above purpose, the technical solution adopted by the present invention is: to provide a single-unit forty-eight-pulse rectifier transformer, including: an oil tank, two regulating transformer bodies, and two rectifier transformer bodies. The regulating transformer bodies and the rectifier transformer bodies are arranged in the oil tank. The two regulating transformer bodies are the first regulating transformer body and the second regulating transformer body, and the two rectifier transformer bodies are the first rectifier transformer body and the second rectifier transformer body. The first regulating transformer body and the first rectifier transformer body form a first set of equivalent twenty-four-pulse output systems, and the second regulating transformer body and the second rectifier transformer body form a second set of equivalent twenty-four-pulse output systems.
[0007] In a possible implementation manner, the first regulating transformer body includes a first regulating iron core, a first offset winding, a first basic winding, and a first tap winding. The first regulating iron core is a horizontally placed E-shaped iron core. The first offset winding, the first basic winding, and the first tap winding are sequentially arranged outside the vertical iron core of the first regulating iron core, and the offset angle of the first offset winding is 3.75°.
[0008] In one possible implementation, the second voltage-regulating transformer body includes a second voltage-regulating iron core, a second offset winding, a second basic winding, and a second tap winding. The second voltage-regulating iron core is a horizontally placed Japanese-shaped iron core. The second offset winding, the second basic winding, and the second tap winding are sequentially arranged on the outside of the vertical iron core of the second voltage-regulating iron core. The offset angle of the second offset winding is 3.75°.
[0009] In a possible implementation, the offset angles of the first offset winding and the second offset winding are respectively set to the left or right, and the offset angles of the first offset winding and the second offset winding are set oppositely.
[0010] In one possible implementation, the first rectifier transformer body includes a first rectifier core, a first high-voltage basic winding, a first high-voltage offset winding and a first low-voltage winding. The first rectifier core includes a first upper rectifier core, a first middle-upper rectifier core, a first middle-lower rectifier core and a first lower rectifier core stacked in sequence from top to bottom. The first upper rectifier core, the first middle-upper rectifier core, the first middle-lower rectifier core and the first lower rectifier core are horizontally placed "S"-shaped cores. A group of the first high-voltage basic winding, a group of the first high-voltage offset winding and a group of the first low-voltage winding are arranged in sequence on the outer side of the vertical core of each layer of the "S"-shaped core. The first high-voltage basic windings of each layer are arranged in series, the first high-voltage offset windings of each layer are arranged in series, and the first low-voltage windings of each layer are arranged in series.
[0011] In one possible implementation, the winding arrangement of the first upper rectifier core is such that the first high-voltage basic winding adopts an extended triangle connection, the first high-voltage offset winding is phase-shifted by +7.5°, and the first low-voltage winding adopts a triangle connection; the winding arrangement of the first middle-upper rectifier core is such that the first high-voltage basic winding adopts an extended triangle connection, the first high-voltage offset winding is phase-shifted by +7.5°, and the first low-voltage winding adopts a star connection; the winding arrangement of the first middle-lower rectifier core is such that the first high-voltage basic winding adopts an extended triangle connection, the first high-voltage offset winding is phase-shifted by -7.5°, and the first low-voltage winding adopts a triangle connection; the winding arrangement of the first lower rectifier core is such that the first high-voltage basic winding adopts an extended triangle connection, the first high-voltage offset winding is phase-shifted by -7.5°, and the first low-voltage winding adopts a star connection.
[0012] In a possible implementation, the second rectifier transformer body has the same structure and the same winding arrangement as the first rectifier transformer body.
[0013] In a possible implementation, the windings of the first voltage-regulating transformer body and the second voltage-regulating transformer body each use an on-load tap changer, the first voltage-regulating transformer body and the second voltage-regulating transformer body are arranged in a straight line on the left and right, and are connected as a whole by a voltage-regulating iron core clamp.
[0014] In a possible implementation, the first rectifier transformer body and the second rectifier transformer body are arranged in a straight line along their length direction and connected as a whole by a rectifier core clamp.
[0015] In a possible implementation, the voltage regulating transformer body and the rectifier transformer body are perpendicular to their length directions and arranged side by side in a two-line shape.
[0016] The beneficial effects of the single-unit 48-pulse rectifier transformer provided by the present invention are:
[0017] Compared with the prior art, an oil tank is provided, in which two sets of voltage-regulating transformer bodies and two sets of rectifier transformer bodies are arranged, namely a first voltage-regulating transformer body, a second voltage-regulating transformer body, a first rectifier transformer body, and a second rectifier transformer body. The first voltage-regulating transformer body and the first rectifier transformer body together constitute a first equivalent 24-pulse output system, and the second voltage-regulating transformer body and the second rectifier transformer body together constitute a second equivalent 24-pulse output system. The two equivalent 24-pulse output systems together constitute a complete single-unit 48-pulse rectifier transformer system, achieving a single-unit equivalent 48-pulse output and greatly reducing the harmonic content fed back to the power grid by the rectifier transformer. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0019] Figure 1 A schematic structural diagram of a first voltage regulating transformer body used in an embodiment of the present invention;
[0020] Figure 2 A schematic structural diagram of a second voltage regulating transformer body used in an embodiment of the present invention;
[0021] Figure 3 A schematic structural diagram of a first rectifier transformer body used in an embodiment of the present invention;
[0022] Figure 4 A schematic structural diagram of a second rectifier transformer body used in an embodiment of the present invention;
[0023] Figure 5 A schematic diagram of the internal structure of a rectifier transformer provided in an embodiment of the present invention.
[0024] In the picture:
[0025] 100. First voltage-regulating transformer body; 101. First voltage-regulating iron core; 102. First offset winding; 103. First basic winding; 104. First tap winding;
[0026] 200, second voltage-regulating transformer body; 201, second voltage-regulating iron core; 202, second offset winding; 203, second basic winding; 204, second tap winding;
[0027] 300, first rectifier transformer body; 301, first high-voltage basic winding; 302, first high-voltage offset winding; 303, first low-voltage winding; 304, first upper rectifier core; 305, first middle-upper rectifier core; 306, first middle-lower rectifier core; 307, first lower rectifier core;
[0028] 400, second rectifier transformer body; 401, second high-voltage basic winding; 402, second high-voltage offset winding; 403, second low-voltage winding; 404, second upper rectifier core; 405, second middle-upper rectifier core; 406, second middle-lower rectifier core; 407, second lower rectifier core;
[0029] 500, oil tank; 600, on-load tap-changer; 700, voltage regulating core clamp; 800, rectifier core clamp; 900, capsule-type oil conservator; 1000, detachable plate radiator. DETAILED DESCRIPTION
[0030] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0031] Please refer to Figures 1 to 5 A specific embodiment of a single-unit 48-pulse rectifier transformer provided by the present invention is now described. The transformer comprises an oil tank 500, two sets of voltage-regulating transformer bodies, and two sets of rectifier transformer bodies. The voltage-regulating transformer bodies and the rectifier transformer bodies are disposed within the oil tank 500. The two sets of voltage-regulating transformer bodies are a first voltage-regulating transformer body 100 and a second voltage-regulating transformer body 200. The two sets of rectifier transformer bodies are a first rectifier transformer body 300 and a second rectifier transformer body 400. The first voltage-regulating transformer body 100 and the first rectifier transformer body 300 form a first equivalent 24-pulse output system, and the second voltage-regulating transformer body 200 and the second rectifier transformer body 400 form a second equivalent 24-pulse output system.
[0032] A single - unit forty - eight - pulse rectifier transformer provided by the present invention, compared with the prior art, is provided with an oil tank 500. Inside the oil tank 500, there are two sets of regulating transformer bodies and two sets of rectifying transformer bodies, namely the first regulating transformer body 100, the second regulating transformer body 200, the first rectifying transformer body 300, and the second rectifying transformer body 400. The first regulating transformer body 100 and the first rectifying transformer body 300 together form the first set of equivalent twenty - four - pulse output systems, and the second regulating transformer body 200 and the second rectifying transformer body 400 together form the second set of equivalent twenty - four - pulse output systems. The two sets of equivalent twenty - four - pulse output systems together form a complete set of single - unit forty - eight - pulse rectifier transformer systems, achieving single - unit equivalent forty - eight - pulse output and greatly reducing the harmonic content fed back from the rectifier transformer to the power grid.
[0033] As a specific embodiment of a single - unit forty - eight - pulse rectifier transformer provided by the present invention, please refer to Figure 1 , the first regulating transformer body 100 includes a first regulating iron core 101, a first offset winding 102, a first basic winding 103, and a first tap - changing winding 104. The first regulating iron core 101 is a horizontally - placed figure - eight - shaped iron core. The first offset winding 102, the first basic winding 103, and the first tap - changing winding 104 are sequentially arranged outside the vertical iron core of the first regulating iron core 101, and the offset angle of the first offset winding 102 is 3.75°.
[0034] Specifically, please refer to Figure 1 , the first regulating transformer body 100 includes a first regulating iron core 101. The first regulating iron core 101 is a horizontally - placed figure - eight - shaped iron core, that is, it includes three groups of vertically - arranged iron cores. Horizontal iron cores are provided at both ends of adjacent vertical iron cores to connect the vertical iron cores. The first offset winding 102, the first basic winding 103, and the first tap - changing winding 104 are sequentially arranged outside the three groups of vertical iron cores, and the offset angle of the first offset winding 102 is 3.75°.
[0035] As a specific embodiment of a single - unit forty - eight - pulse rectifier transformer provided by the present invention, please refer to Figure 2 , the second regulating transformer body 200 includes a second regulating iron core 201, a second offset winding 202, a second basic winding 203, and a second tap - changing winding 204. The second regulating iron core 201 is a horizontally - placed figure - eight - shaped iron core. The second offset winding 202, the second basic winding 203, and the second tap - changing winding 204 are sequentially arranged outside the vertical iron core of the second regulating iron core 201, and the offset angle of the second offset winding 202 is 3.75°.
[0036] Specifically, please refer to Figure 2, the second voltage regulating transformer body 200 includes a second voltage regulating iron core 201, and the second voltage regulating iron core 201 is a horizontally arranged E-shaped iron core, that is, it includes three groups of vertically arranged iron cores. Horizontal transverse yokes are provided at both ends of adjacent vertical iron cores to connect the vertical iron cores. The second offset winding 202, the second basic winding 203, and the second tap winding 204 are sequentially arranged on the outer sides of the three groups of vertical iron cores, and the offset angle of the second offset winding 202 is 3.75°.
[0037] As a specific embodiment of a single-unit forty-eight-pulse rectifier transformer provided by the present invention, please refer to Figure 1 , Figure 2 , the offset angles of the first offset winding 102 and the second offset winding 202 are set to the left or right respectively, and the offset angles of the first offset winding 102 and the second offset winding 202 are set in the opposite direction.
[0038] Specifically, please refer to Figure 1 , Figure 2 , the offset angles of the first offset winding 102 and the second offset winding 202 are set in the opposite direction; the first offset winding 102 is offset to the right, and the second offset winding 202 is offset to the left; or the first offset winding 102 is offset to the left, and the second offset winding 202 is offset to the right.
[0039] As a specific embodiment of a single-unit forty-eight-pulse rectifier transformer provided by the present invention, please refer to Figure 3 , the first rectifier transformer body 300 includes a first rectifier iron core, a first high-voltage basic winding 301, a first high-voltage offset winding 302, and a first low-voltage winding 303. The first rectifier iron core includes a first upper rectifier iron core 304, a first middle-upper rectifier iron core Figure 3 305, a first middle-lower rectifier iron core 306, and a first lower rectifier iron core 307 stacked in sequence from top to bottom. The first upper rectifier iron core 304, the first middle-upper rectifier iron core 305, the first middle-lower rectifier iron core 306, and the first lower rectifier iron core 307 are horizontally arranged E-shaped iron cores. A group of first high-voltage basic windings 301, a group of first high-voltage offset windings 302, and a group of first low-voltage windings 303 are sequentially arranged on the outer sides of the vertical iron cores of each layer of the E-shaped iron core. The first high-voltage basic windings 301 of each layer are arranged in columns, the first high-voltage offset windings 302 of each layer are arranged in columns, and the first low-voltage windings 303 of each layer are arranged in columns.
[0040] Specifically, please refer to Figure 3, the first rectifier transformer body 300 includes a first rectifier iron core, a first high-voltage basic winding 301, a first high-voltage offset winding 302, and a first low-voltage winding 303. The first rectifier iron core includes four horizontally arranged "day" - shaped iron cores stacked in sequence. The upper and lower end faces of adjacent "day" - shaped iron cores coincide. A common horizontal yoke is provided between the "day" - shaped iron core in the upper layer and the "day" - shaped iron core in the lower layer. That is, the vertical iron cores of the four - layer "day" - shaped iron cores form an iron - core arrangement grid of four rows and three columns. Using a layered design, a common horizontal yoke is provided between each layer, solving the problem of difficult winding turn matching under low voltage. Horizontal yokes are provided at both ends of adjacent vertical iron cores to connect the vertical iron cores. According to the iron - core arrangement position, the first rectifier iron core includes a first upper - layer rectifier iron core 304, a first middle - upper rectifier iron core 305, a first middle - lower rectifier iron core 306, and a first lower - layer rectifier iron core 307 stacked in sequence from top to bottom. For each layer of the three vertical iron cores, a set of first high - voltage basic winding 301, a set of first high - voltage offset winding 302, and a set of first low - voltage winding 303 are arranged in sequence. And the first high - voltage basic windings 301 of different layers are arranged in columns, the first high - voltage offset windings 302 of different layers are arranged in columns, and the first low - voltage windings 303 of different layers are arranged in columns.
[0041] As a specific embodiment of a single - machine forty - eight - pulse rectifier transformer provided by the present invention, please refer to Figure 3 , for the winding arrangement of the first upper - layer rectifier iron core 304, the first high - voltage basic winding 301 adopts an extended delta connection, the first high - voltage offset winding 302 is phase - shifted by + 7.5°, and the first low - voltage winding 303 adopts a delta connection; for the winding arrangement of the first middle - upper rectifier iron core 305, the first high - voltage basic winding 301 adopts an extended delta connection, the first high - voltage offset winding 302 is phase - shifted by + 7.5°, and the first low - voltage winding 303 adopts a star connection; for the winding arrangement of the first middle - lower rectifier iron core 306, the first high - voltage basic winding 301 adopts an extended delta connection, the first high - voltage offset winding 302 is phase - shifted by - 7.5°, and the first low - voltage winding 303 adopts a delta connection; for the winding arrangement of the first lower - layer rectifier iron core 307, the first high - voltage basic winding 301 adopts an extended delta connection, the first high - voltage offset winding 302 is phase - shifted by - 7.5°, and the first low - voltage winding 303 adopts a star connection.
[0042] Specifically, please refer to Figure 3 , for the first rectifier transformer body 300, the windings of different layers have different phase - shift angles and connection methods. All the windings of the four - layer iron core have relatively independent magnetic - circuit systems. When designing the number of turns, they are not restricted by the magnetic circuit and can be flexibly matched to achieve accurate phase - shift angles and valve - side voltage outputs.
[0043] As a specific embodiment of a single - machine forty - eight - pulse rectifier transformer provided by the present invention, please refer to Figure 4, the second rectifier transformer body 400 has the same structure and winding arrangement as the first rectifier transformer body 300.
[0044] Specifically, please refer to Figure 4 , the second rectifier transformer body 400 and the first rectifier transformer body 300 adopt the same iron core structure and winding arrangement. The second rectifier transformer body 400 includes a second rectifier iron core, a second high-voltage basic winding 401, a second high-voltage offset winding 402, and a second low-voltage winding 403. The second rectifier iron core includes four sets of horizontally arranged "day" - shaped iron cores stacked in sequence. The upper and lower end faces of the "day" - shaped iron cores in adjacent layers coincide. That is, the vertical iron cores of the four - layer "day" - shaped iron cores form an iron core arrangement grid of four rows and three columns. Horizontal iron core connecting vertical iron cores are arranged at both ends of adjacent vertical iron cores. According to the iron core arrangement position, the second rectifier iron core includes a second upper - layer rectifier iron core 404, a second middle - upper rectifier iron core 405, a second middle - lower rectifier iron core 406, and a second lower - layer rectifier iron core 407 stacked in sequence from top to bottom. One set of second high - voltage basic winding 401, one set of second high - voltage offset winding 402, and one set of second low - voltage winding 403 are sequentially arranged on the three vertical iron cores of each layer. And the second high - voltage basic windings 401 in different layers are arranged in columns, the second high - voltage offset windings 402 in different layers are arranged in columns, and the second low - voltage windings 403 in different layers are arranged in columns.
[0045] For the winding arrangement of the second upper - layer rectifier iron core 404, the second high - voltage basic winding 401 adopts an extended delta connection method, the second high - voltage offset winding 402 has a phase shift of + 7.5°, and the second low - voltage winding 403 adopts a delta connection method; for the winding arrangement of the second middle - upper rectifier iron core 405, the second high - voltage basic winding 401 adopts an extended delta connection method, the second high - voltage offset winding 402 has a phase shift of + 7.5°, and the second low - voltage winding 403 adopts a star connection method; for the winding arrangement of the second middle - lower rectifier iron core 406, the second high - voltage basic winding 401 adopts an extended delta connection method, the second high - voltage offset winding 402 has a phase shift of - 7.5°, and the second low - voltage winding 403 adopts a delta connection method; for the winding arrangement of the second lower - layer rectifier iron core 407, the second high - voltage basic winding 401 adopts an extended delta connection method, the second high - voltage offset winding 402 has a phase shift of - 7.5°, and the second low - voltage winding 403 adopts a star connection method
[0046] As a specific embodiment of the single - machine forty - eight - pulse rectifier transformer provided by the present invention, please refer to Figures 1 to 5 , each of the windings of the first regulating transformer body 100 and the second regulating transformer body 200 uses an on - load tap - changing switch 600. The first regulating transformer body 100 and the second regulating transformer body 200 are arranged side - by - side in a straight line and are connected as a whole through a regulating iron core clamp 700.
[0047] Specifically, please refer to Figures 1 to 5Two on-load tap changers 600 are provided, which are respectively connected to the windings of the first voltage-regulating transformer body 100 and the second voltage-regulating transformer body 200. The two on-load tap changers 600 are respectively arranged on the side of the first voltage-regulating transformer body 100 and the second voltage-regulating transformer body 200 that are away from each other. The first voltage-regulating transformer body 100 and the second voltage-regulating transformer body 200 are arranged in a row, using a straight line arrangement on the left and right. The first voltage-regulating core 101 of the first voltage-regulating transformer body 100 and the second voltage-regulating core 201 of the second voltage-regulating transformer body 200 are connected using a voltage-regulating core clamp 700.
[0048] As a specific implementation of the single-machine 48-pulse rectifier transformer provided by the present invention, please refer to Figures 1 to 5 The first rectifier transformer body 300 and the second rectifier transformer body 400 are arranged in a straight line along the length direction thereof and are connected as a whole by the rectifier core clamp 800 .
[0049] For details, please refer to Figures 1 to 5 The first rectifier transformer body 300 and the second rectifier transformer body 400 are arranged in a row. In the length direction of the first rectifier transformer body 300 and the second rectifier transformer body 400, they are arranged in a straight line on the left and right. The first rectifier transformer body 300 is arranged on the left side of the second rectifier transformer body 400, and the rectifier core clamp 800 is used to connect the first rectifier core of the first rectifier transformer body 300 and the second rectifier core of the second rectifier transformer body 400.
[0050] As a specific implementation of the single-machine 48-pulse rectifier transformer provided by the present invention, please refer to Figures 1 to 5 The voltage regulating transformer body and the rectifier transformer body are perpendicular to their length direction and arranged side by side in a two-shaped pattern.
[0051] For details, please refer to Figures 1 to 5 In the lengthwise direction of the first and second voltage-regulating transformer bodies 100 and 200, they are arranged in a straight line, with the first voltage-regulating transformer body 100 located to the left of the second voltage-regulating transformer body 200. The voltage-regulating transformer bodies and the rectifier transformer bodies are arranged in a row, in a two-shaped front-to-back arrangement. In the lengthwise direction perpendicular to the first rectifier transformer body 300, the first voltage-regulating transformer body 100 is located in front of the first rectifier transformer body 300, and the second voltage-regulating transformer body 200 is located in front of the second rectifier transformer body 400. By disposing the first offset winding 102, the second offset winding 202, the first high-voltage offset winding 302, and the second high-voltage offset winding 402 on the high-voltage side of the voltage-regulating transformer body and the rectifier transformer body, and using star and delta connections on the low-voltage side of the rectifier transformer, a single-machine equivalent 48-pulse output is achieved.
[0052] As a specific implementation of the single-machine 48-pulse rectifier transformer provided by the present invention, please refer to Figure 5The oil tank 500 adopts a full vacuum type oil tank 500, and the oil tank 500 and the pieces will not have unacceptable permanent deformation under a positive pressure of 100kPa and a negative pressure of 133Pa.
[0053] As a specific implementation of the single-machine 48-pulse rectifier transformer provided by the present invention, please refer to Figure 5 , the cooling device adopts a detachable plate radiator 1000.
[0054] As a specific implementation of the single-machine 48-pulse rectifier transformer provided by the present invention, please refer to Figure 5 The capsule oil conservator 900 is used to adjust the volume change of the transformer oil in the rectifier transformer due to temperature change. The capsule oil conservator 900 avoids the transformer oil from contacting with the air, thereby preventing the transformer oil from oxidizing and deteriorating.
[0055] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. A single-machine 48-pulse rectifier transformer, characterized in that: Comprising: An oil tank, two sets of regulating transformer bodies and two sets of rectifying transformer bodies. The regulating transformer bodies and the rectifying transformer bodies are arranged in the oil tank. The two sets of regulating transformer bodies are the first regulating transformer body and the second regulating transformer body, and the two sets of rectifying transformer bodies are the first rectifying transformer body and the second rectifying transformer body. The first regulating transformer body and the first rectifying transformer body form a first set of equivalent twenty-four pulse output systems, and the second regulating transformer body and the second rectifying transformer body form a second set of equivalent twenty-four pulse output systems. The first rectifying transformer body includes a first rectifying iron core, a first high-voltage basic winding, a first high-voltage offset winding and a first low-voltage winding. The first rectifying iron core includes a first upper rectifying iron core, a first middle-upper rectifying iron core, a first middle-lower rectifying iron core and a first lower rectifying iron core stacked in sequence from top to bottom. The first upper rectifying iron core, the first middle-upper rectifying iron core, the first middle-lower rectifying iron core and the first lower rectifying iron core are horizontally arranged E-shaped iron cores. On the outer sides of the vertical iron cores of the E-shaped iron cores of each layer, a set of the first high-voltage basic winding, a set of the first high-voltage offset winding and a set of the first low-voltage winding are sequentially arranged. The first high-voltage basic windings of each layer are arranged in columns, the first high-voltage offset windings of each layer are arranged in columns, and the first low-voltage windings of each layer are arranged in columns; The winding arrangement of the first upper rectifying iron core is that the first high-voltage basic winding adopts an extended delta connection, the first high-voltage offset winding is phase-shifted by +7.5°, and the first low-voltage winding adopts a delta connection; The winding arrangement of the first middle-upper rectifying iron core is that the first high-voltage basic winding adopts an extended delta connection, the first high-voltage offset winding is phase-shifted by +7.5°, and the first low-voltage winding adopts a star connection; The winding arrangement of the first middle-lower rectifying iron core is that the first high-voltage basic winding adopts an extended delta connection, the first high-voltage offset winding is phase-shifted by -7.5°, and the first low-voltage winding adopts a delta connection; The winding arrangement of the first lower rectifying iron core is that the first high-voltage basic winding adopts an extended delta connection, the first high-voltage offset winding is phase-shifted by -7.5°, and the first low-voltage winding adopts a star connection.
2. A single-machine 48-pulse rectifier transformer as claimed in claim 1, characterized in that: The first regulating transformer body includes a first regulating iron core, a first offset winding, a first basic winding and a first tap winding. The first regulating iron core is a horizontally arranged E-shaped iron core. The first offset winding, the first basic winding and the first tap winding are sequentially arranged on the outer sides of the vertical iron cores of the first regulating iron core. The offset angle of the first offset winding is 3.75°.
3. A single-machine 48-pulse rectifier transformer as claimed in claim 2, characterized in that: The second regulating transformer body includes a second regulating iron core, a second offset winding, a second basic winding and a second tap winding. The second regulating iron core is a horizontally arranged E-shaped iron core. The second offset winding, the second basic winding and the second tap winding are sequentially arranged on the outer sides of the vertical iron cores of the second regulating iron core. The offset angle of the second offset winding is 3.75°.
4. A single-machine 48-pulse rectifier transformer as claimed in claim 3, characterized in that: The offset angles of the first offset winding and the second offset winding are respectively set to the left or right, and the offset angles of the first offset winding and the second offset winding are set oppositely.
5. A single-machine 48-pulse rectifier transformer as claimed in claim 1, characterized in that: The second rectifier transformer body has the same structure and the same winding arrangement as the first rectifier transformer body.
6. A single-machine 48-pulse rectifier transformer as claimed in claim 1, characterized in that: The windings of the first voltage regulating transformer body and the second voltage regulating transformer body are each connected with an on-load tap changer. The first voltage-regulating transformer body and the second voltage-regulating transformer body are arranged in a straight line on the left and right, and are connected into a whole through a voltage-regulating iron core clamp.
7. A single-machine 48-pulse rectifier transformer as claimed in claim 1, characterized in that: The first rectifier transformer body and the second rectifier transformer body are arranged in a straight line on the left and right along the length direction thereof, and are connected into a whole through a rectifier core clamp.
8. A single-machine 48-pulse rectifier transformer as claimed in claim 1, characterized in that: The voltage regulating transformer body and the rectifier transformer body are perpendicular to the length direction thereof and are arranged side by side front and back in a two-line shape.