A 24-pulse low-voltage phase-shifting rectifier transformer body structure

Abstract

The utility model relates to a kind of 24-pulse low-voltage phase-shifting rectifier transformer's body structure, comprising: iron core;High-voltage winding is wound on iron core;Low-voltage winding is wound outside high-voltage winding, and low-voltage winding includes multiple groups of windings;Multiple groups of low-voltage windings have different phase connection modes, for realizing multi-pulse rectifier output by phase shifting;Multiple groups of low-voltage windings are arranged along the axial direction in the body structure, and are configured as multi-branch parallel structure;Rectifier transformer is suitable for cooperating with rectifier device to output 24-pulse rectifier voltage.The utility model solves the technical problems of existing low-voltage side phase-shifting scheme, such as complex winding design, uneven heat distribution, limited space arrangement and insufficient lightning impact resistance.

Description

Technical Field

[0001] This utility model relates to the body structure of a 24-pulse low-voltage phase-shifting rectifier transformer. Background Technology

[0002] With the development of new energy technologies, especially in applications with extremely high power quality requirements such as hydrogen production, electrolytic metallurgy, and specialty chemicals, higher demands are being placed on the quality, stability, and harmonic control of the DC voltage waveform output by rectifier equipment. Traditional rectifier systems, such as 6-pulse or 12-pulse rectifier structures, although relatively simple in circuit structure and low in implementation cost, have large harmonic components in their output current, which can easily interfere with the power system, leading to a decrease in power factor and power utilization, and in severe cases, even affecting the stable operation of downstream equipment.

[0003] Increasing the pulse number of a rectifier system is an effective way to suppress harmonics and optimize the quality of output power. Among them, the 24-pulse rectifier system is widely used in high-power industrial rectifier equipment due to its higher waveform smoothness, lower harmonic content, and better power factor compensation characteristics.

[0004] Currently, the commonly used 24-pulse rectification methods mainly include two types: high-voltage side phase shifting and low-voltage side phase shifting. Among them, high-voltage side phase shifting usually requires a dual-body structure (such as left-right symmetrical or top-bottom stacked), which is not only structurally complex and occupies a large space, but also has high requirements for main materials, insulation and processing technology, resulting in a significant increase in manufacturing costs, making it difficult to meet the requirements of small and medium capacity rectifier equipment for economy and compact structure.

[0005] In comparison, the low-voltage phase-shifting structure can achieve multi-phase output in a single-body configuration, offering advantages such as compact structure, good manufacturability, and low cost, making it an effective alternative for achieving high pulse number rectification. However, existing low-voltage phase-shifting schemes still suffer from technical bottlenecks in practical engineering applications, including complex winding design, uneven heat distribution, limited winding layout space, and insufficient resistance to lightning strikes. Therefore, there is an urgent need to propose a novel body structure design that achieves a good balance between performance, structure, and cost. Utility Model Content:

[0006] The purpose of this utility model is to overcome the shortcomings of the prior art and provide a body structure for a 24-pulse low-voltage phase-shifting rectifier transformer.

[0007] A core structure for a 24-pulse low-voltage phase-shifting rectifier transformer includes:

[0008] Iron core;

[0009] A high-voltage winding wound on the iron core;

[0010] A low-voltage winding is wound outside the high-voltage winding, and the low-voltage winding includes multiple sets of windings;

[0011] The multiple sets of low-voltage windings have different phase connection methods, which are used to achieve multi-pulse rectified output through phase shifting;

[0012] The multiple sets of low-voltage windings are arranged axially in the transformer body structure and form a multi-branch parallel structure.

[0013] The rectifier transformer is suitable for use with a rectifier device to output a 24-pulse rectified voltage.

[0014] Furthermore, the multiple sets of low-voltage windings include four sets, namely a first low-voltage coil connected by Y, a second low-voltage coil connected by D, a first phase-shifting winding, and a second phase-shifting winding.

[0015] Furthermore, the phase shift angles of the first phase-shifting winding and the second phase-shifting winding are +15° and +45°, respectively.

[0016] Furthermore, the low-voltage winding adopts a double-disc or four-disc structure and is arranged in an axially staggered manner.

[0017] Furthermore, the number of parallel branches of the low-voltage winding is six. The first phase-shifting winding includes a third low-voltage coil and a third low-voltage phase-shifting coil, and the second phase-shifting winding includes a fourth low-voltage coil and a fourth low-voltage phase-shifting coil. The first low-voltage coil, the second low-voltage coil, the third low-voltage coil, the third low-voltage phase-shifting coil, the fourth low-voltage coil, and the fourth low-voltage phase-shifting coil are wound on the iron core from top to bottom.

[0018] Furthermore, the phase-shifting winding is double-parallel wound, and a wire is cut off at the winding transposition position and a copper busbar is led out through the radial oil passage for connection.

[0019] Furthermore, the core of the rectifier transformer is a three-phase, three-column structure, constructed using oriented silicon steel sheets with oblique joints.

[0020] Beneficial effects: Compared with the prior art, this utility model proposes a novel and high-performance 24-pulse low-voltage phase-shifting rectifier transformer body structure. By integrating the high-voltage winding and four sets of low-voltage windings with different connection methods (including Y connection, D connection, +15° phase shift and +45° phase shift) on a single iron core structure, 24-pulse rectification output is achieved, which significantly improves the harmonic characteristics and output stability of the rectifier system.

[0021] This structure employs an axially staggered arrangement and a double- or quadruple-panel low-voltage winding design, effectively enhancing short-circuit withstand capability and thermal uniformity. Furthermore, it achieves current sharing and temperature rise balance by dividing the low-voltage side into six parallel branches. In addition, the phase-shifting winding adopts a double-parallel structure, and at the transposition point, the radial lead-out method of the copper busbar optimizes the wiring layout, improving heat dissipation efficiency and simplifying wiring.

[0022] The core adopts a three-phase, three-column structure and utilizes a oriented silicon steel sheet oblique joint lamination process to ensure excellent magnetic performance and low no-load loss, meeting the requirements of modern energy-saving and consumption-reducing electrical equipment.

[0023] While ensuring technical performance, the overall structure effectively reduces the transformer volume by about 30%, lowers manufacturing costs by about 50%, and improves safety, lightning strike resistance, and service life during operation. It is a preferred solution for high-reliability industrial rectifier power supply scenarios (such as hydrogen production). Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the vessel's structure;

[0025] Figure 2 This is a schematic diagram showing the connection of the copper busbar after the conductor is cut off at the winding transposition position;

[0026] In the diagram, 1 is the iron core, 2 is the high-voltage coil, 3 is the first low-voltage coil, 4 is the second low-voltage coil, 5 is the third low-voltage coil, 6 is the third low-voltage phase-shifting coil, 7 is the fourth low-voltage coil, 8 is the fourth low-voltage phase-shifting coil, and 9 is the copper busbar. Detailed Implementation

[0027] To enhance understanding of this utility model, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings. These embodiments are only used to explain the present utility model and do not constitute a limitation on the scope of protection of the present utility model.

[0028] A 24-pulse low-voltage phase-shifting rectifier transformer body structure includes: an iron core 1; a high-voltage winding 2 wound on the iron core 1; and a low-voltage winding wound outside the high-voltage winding 2, the low-voltage winding including multiple sets of windings; the multiple sets of low-voltage windings have different phase connection methods, used to achieve multi-pulse rectification output through phase shifting; the multiple sets of low-voltage windings are arranged axially in the body structure and form a multi-branch parallel structure; the rectifier transformer is suitable for cooperating with a rectifier device to output a 24-pulse rectified voltage.

[0029] This rectifier transformer adopts a single-core structure and achieves 24-pulse rectification through phase-shifting technology on the low-voltage side. Its core principle lies in setting up four sets of low-voltage windings: one Y-connected, one D-connected, one with +15° phase shift, and one with +45° phase shift. The phase difference between the output voltages of every two sets of windings is 15°, forming a total of 24 rectifier pulses, significantly optimizing the rectified waveform and output quality. All low-voltage windings are arranged around the high-voltage winding 2 and along the axial direction of the core 1 to form six parallel branches, ensuring electrical performance and helping to balance the thermal load. The transformer core 1 adopts a three-phase, three-column structure, constructed from oriented silicon steel sheets with oblique joints, reducing no-load losses and enhancing electromagnetic performance. This structure demonstrates significant rationality and efficiency in both electrical design and manufacturing processes.

[0030] In one possible implementation, the multiple sets of low-voltage windings include four sets, namely a first low-voltage coil 3 connected by Y, a second low-voltage coil 4 connected by D, a first phase-shifting winding, and a second phase-shifting winding.

[0031] In this embodiment, the low-voltage side has four sets of windings, each employing a different wiring method to achieve the phase shift target: the Y-connected winding and the D-connected winding respectively undertake the main output function, while the first and second phase-shifting windings achieve additional phase shift by designing specific winding turns and wiring methods, forming 24 rectified pulse outputs. This design makes the electrical performance of each set of windings complementary and synergistic, and the staggered arrangement along the axial direction is beneficial for magnetic coupling and balanced heat distribution.

[0032] By combining four sets of low-voltage windings with different connection methods, the required phase shift angle can be accurately achieved. While maintaining a compact structure, the output waveform quality of the rectifier system is enhanced, and the power factor and output stability of the rectifier equipment are effectively improved.

[0033] In one possible implementation, the phase shift angles of the first phase-shifting winding and the second phase-shifting winding are +15° and +45°, respectively.

[0034] In this embodiment, the first phase-shifting winding achieves a +15° phase-shifting output through its winding method and wiring structure design, while the second phase-shifting winding achieves a +45° phase-shifting output by adjusting its winding layout, wire diameter, and number of turns. Thus, combining the two basic phases of the Y-connection and D-connection, a 15° phase difference is maintained between the four winding outputs, thereby achieving the phase configuration required for 24-pulse rectification.

[0035] By using a combination of +15° and +45° phase shift angles, the output voltages of each winding are precisely staggered in phase, achieving high-quality 24-pulse rectification, significantly reducing the total harmonic distortion of the system, and improving the overall performance of the rectifier system.

[0036] In one possible implementation, the low-voltage winding adopts a double-pane or four-pane structure and is arranged in an axially staggered manner.

[0037] The low-voltage winding uses a double- or quadruple-panel structure, leveraging its excellent short-circuit withstand capability, formability, and heat dissipation performance. Simultaneously, it employs a staggered arrangement along the axial direction within the transformer body. This staggered arrangement helps reduce leakage flux coupling strength, optimizes electromagnetic interference, and makes the winding structure more compact. This arrangement, combined with the transformer body's cooling channel design, helps to evenly distribute temperature rise and reduce hotspot temperatures.

[0038] The double- or quadruple-panel winding structure enhances the rectifier transformer's resistance to mechanical shock and short circuits. The axially staggered arrangement not only saves space but also improves heat dissipation performance, effectively controls temperature rise, and enhances equipment lifespan and operational reliability.

[0039] In one possible implementation, the number of parallel branches of the low-voltage winding is six. The first phase-shifting winding includes a third low-voltage coil 5 and a third low-voltage phase-shifting coil 6, and the second phase-shifting winding includes a fourth low-voltage coil 7 and a fourth low-voltage phase-shifting coil 8. The first low-voltage coil 3, the second low-voltage coil 4, the third low-voltage coil 5, the third low-voltage phase-shifting coil 6, the fourth low-voltage coil 7, and the fourth low-voltage phase-shifting coil 8 are wound sequentially on the iron core 1 from top to bottom.

[0040] In this embodiment, to reduce the current carried by each winding and distribute the heat load, the low-voltage winding structure is subdivided into six parallel branches, each consisting of three basic coils and three corresponding phase-shifting coils. Each coil is wound sequentially downwards from the top of the core 1 along the axial direction, forming a symmetrical and balanced wiring structure that ensures good electromagnetic balance. The branch structure maintains consistency in the number of turns, voltage level, and geometric dimensions, achieving good load balance and electrical coordination.

[0041] The six-branch parallel structure averages the current density and temperature rise distribution of each winding, reduces the risk of local overheating, and improves the thermal stability and overall safety of the device structure, making it suitable for high-efficiency operation in high-current output applications.

[0042] In one possible implementation, the phase-shifting winding is double-parallel wound, and a wire is cut off at the winding transposition position and connected to a copper busbar 9 through a radial oil passage.

[0043] In this embodiment, the phase-shifting winding employs a parallel winding method with two conductors to improve conductivity and winding density. One of the conductors is cut off in the transposition region and a copper busbar 9 is led out through a radial oil channel to connect to the external circuit. This design simplifies the winding lead-out method, reduces the number of outgoing wires, lowers the complexity of lead-wire crossings, and optimizes the wiring path and insulation layer thickness distribution, thereby improving heat convection efficiency.

[0044] The dual parallel design enhances current carrying capacity, while the 9-lead copper busbar reduces the number of connectors and strengthens the structure, effectively saving space, reducing thermal resistance, and improving heat dissipation efficiency, enabling the phase-shifting winding to maintain excellent performance and safety margin under high load conditions.

[0045] In one possible implementation, the rectifier transformer core is a three-phase, three-column structure, constructed from oriented silicon steel sheets with oblique joints.

[0046] The core adopts a standard three-phase, three-column structure, with each column carrying one phase of magnetic flux. The symmetrical structure and closed magnetic circuit help reduce magnetic loss and leakage inductance coupling. The oriented silicon steel sheets provide excellent magnetic permeability, and the slanted joint lamination process effectively reduces no-load loss and excitation current, improves the core's response characteristics under high frequency or impulse voltage, enhances vibration resistance, and improves assembly accuracy.

[0047] The three-phase, three-column core design features a compact structure and uniform magnetic field distribution. Combined with the slanted joint technology, it can effectively control the no-load current, improve power conversion efficiency, reduce noise and operating energy consumption, and enhance the operational stability and energy-saving effect of the rectifier transformer.

[0048] Working principle: Through the design of multiple windings on the low-voltage side, the rectifier system achieves high pulse number output, thereby optimizing the output current waveform, reducing harmonic content, and improving the stability and power quality of the rectifier equipment.

[0049] Specifically, the transformer structure incorporates four sets of low-voltage windings, employing Y-connection, Δ-connection, and phase-shifting connection methods with +15° and +45° phase offsets, respectively. By interpolating the phases between different windings, a rectifier structure with 6 pulses per phase and a total of 24 pulses across the three phases is constructed, significantly improving the smoothness and continuity of the rectified output and suppressing the generation of harmonic components.

[0050] To further optimize the thermal field distribution and current-carrying performance, each low-voltage winding is further divided into multiple branches operating in parallel, forming an axially split six-branch parallel structure. This configuration not only helps to average the temperature rise of each winding and avoid local hot spots, but also enhances the operational reliability of the transformer under high-current conditions.

[0051] Meanwhile, the phase-shifting winding adopts double parallel winding and leads out copper busbar 9 through radial oil channels, effectively simplifying the lead structure, improving heat dissipation efficiency and reducing wiring complexity. The high-voltage winding 2 and the low-voltage winding are wound sequentially outside the three-phase three-limb iron core. The iron core adopts a oriented silicon steel sheet slant joint lamination process, which further reduces no-load loss and excitation current, and improves overall electromagnetic performance.

[0052] In summary, this utility model achieves 24-pulse rectified output in a single-body structure through the coordinated design of low-voltage side phase shift and multi-winding parallel structure. It has comprehensive advantages of compact structure, low cost and excellent performance, and is particularly suitable for rectifier system application scenarios with strict requirements for power quality and harmonic control.

[0053] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A core structure for a 24-pulse low-voltage phase-shifting rectifier transformer, characterized in that, include: Iron core; A high-voltage winding wound on the iron core; A low-voltage winding is wound outside the high-voltage winding, and the low-voltage winding includes multiple sets of windings; The multiple sets of low-voltage windings have different phase connection methods, which are used to achieve multi-pulse rectified output through phase shifting; The multiple sets of low-voltage windings are arranged axially in the transformer body structure and form a multi-branch parallel structure. The rectifier transformer is suitable for use with a rectifier device to output a 24-pulse rectified voltage.

2. The vessel body structure according to claim 1, characterized in that, The multiple low-voltage windings include four groups: a first low-voltage coil connected by Y, a second low-voltage coil connected by D, a first phase-shifting winding, and a second phase-shifting winding.

3. The vessel body structure according to claim 2, characterized in that, The phase shift angles of the first phase-shifting winding and the second phase-shifting winding are +15° and +45°, respectively.

4. The vessel body structure according to claim 3, characterized in that, The low-voltage winding adopts a double-disc or four-disc structure and is arranged in an axially staggered manner.

5. The vessel body structure according to claim 4, characterized in that, The number of parallel branches of the low-voltage winding is six. The first phase-shifting winding includes a third low-voltage coil and a third low-voltage phase-shifting coil. The second phase-shifting winding includes a fourth low-voltage coil and a fourth low-voltage phase-shifting coil. The first low-voltage coil, the second low-voltage coil, the third low-voltage coil, the third low-voltage phase-shifting coil, the fourth low-voltage coil, and the fourth low-voltage phase-shifting coil are wound on the iron core from top to bottom.

6. The vessel body structure according to claim 5, characterized in that, The phase-shifting winding is double-parallel winding, and a wire is cut off at the winding transposition position and a copper busbar is led out through the radial oil passage for connection.

7. The vessel body structure according to claim 6, characterized in that, The core of the rectifier transformer is a three-phase, three-column structure, constructed from oriented silicon steel sheets with oblique joints.

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