Multi-phase transformer

Abstract

The utility model discloses a multiphase transformer which comprises a first iron core column, a second iron core column and a third iron core column, and the first iron core column, the second iron core column and the third iron core column are respectively provided with a first winding, a second winding, a third winding, a fourth winding and a fifth winding. By adopting multi-phase rectification and the connection relation among the first winding, the second winding, the third winding, the fourth winding and the fifth winding which are arranged on the first iron core column, the second iron core column and the third iron core column, the harmonic content of input current can be reduced, so that pollution to a power grid is reduced, the power factor of a system can be improved, and the service life of the system is prolonged. Due to the fact that output current ripples are reduced, the size and cost of a filter can be reduced, switching loss can be reduced, the overall efficiency of a rectification system can be improved, the power grid reactive power and harmonic limitation requirements of industrial application cannot be exceeded, and influences on a power grid and harmonic interference generated on other electrical equipment are reduced.

Description

Technical Field

[0001] This utility model relates to the field of transformer technology, and in particular to a multiphase transformer. Background Technology

[0002] Multiphase rectification technology in charging rectifier cabinets is a method to improve rectification efficiency and reduce harmonic pollution from the power grid. The transformer utilizes the principle of electromagnetic induction to change AC voltage. Its main components include coils and an iron core, and its main functions include voltage transformation, current transformation, impedance transformation, isolation, and voltage stabilization. The multiphase autotransformer is a type of transformer and a core component for realizing AC-DC rectification at power frequency. It is widely used in medium- and high-power frequency converter systems and has advantages such as strong adaptability to mains power supply environments, strong resistance to load surges, and high reliability.

[0003] Traditional power frequency AC-DC rectification uses "3-phase 6-pulse" power frequency AC-DC rectification, and its core component is a three-phase transformer. However, this method generates large input current harmonics, which exceed the power grid reactive power and harmonic limits for industrial applications. This has a significant impact on the power grid and causes serious harmonic interference to other electrical equipment. Utility Model Content

[0004] The main purpose of this invention is to propose a multiphase transformer that aims to solve the problem of generating large input current harmonics.

[0005] To achieve the above objectives, this utility model proposes a multiphase transformer, comprising a first core column, a second core column, and a third core column, wherein a first winding, a second winding, a third winding, a fourth winding, and a fifth winding are provided on the first core column, the second core column, and the third core column.

[0006] The first end of the first winding on the first iron core column is connected to the first end of the fifth winding on the second iron core column and the first end of the second winding on the second iron core column, respectively. The second end of the second winding on the second iron core column is connected to the first end of the third winding on the third iron core column and the first end of the fourth winding on the third iron core column, respectively. The second end of the fourth winding on the third iron core column is connected to the first end of the fifth winding on the third iron core column.

[0007] The first end of the first winding on the second iron core column is connected to the second end of the fifth winding on the third iron core column and the first end of the second winding on the third iron core column, respectively. The second end of the second winding on the third iron core column is connected to the first end of the third winding on the first iron core column and the first end of the fourth winding on the first iron core column, respectively. The second end of the fourth winding on the first iron core column is connected to the first end of the fifth winding on the first iron core column.

[0008] The first end of the first winding on the third iron core column is connected to the second end of the fifth winding on the first iron core column and the first end of the second winding on the first iron core column, respectively. The first end of the third winding on the second iron core column is connected to the second end of the second winding on the first iron core column and the first end of the fourth winding on the second iron core column, respectively. The second end of the fourth winding on the second iron core column is connected to the second end of the fifth winding on the second iron core column.

[0009] In one embodiment, a sixth winding is provided on the first iron core post, the second iron core post, and the third iron core post. The first end of the sixth winding on the third iron core post is connected to the second end of the fifth winding on the second iron core post and the second end of the fourth winding on the second iron core post, respectively. The first end of the sixth winding on the first iron core post is connected to the second end of the fifth winding on the third iron core post and the second end of the fourth winding on the third iron core post, respectively. The first end of the sixth winding on the second iron core post is connected to the second end of the fifth winding on the first iron core post and the second end of the fourth winding on the first iron core post.

[0010] In one embodiment, the output windings of the multiphase transformer are the first winding, the third winding, and the sixth winding on each core column.

[0011] In one embodiment, the phase shift angle between the output windings of the multiphase transformer is 20 degrees.

[0012] In one embodiment, the winding directions of each winding on the first iron core column are the same, the winding directions of each winding on the second iron core column are the same, and the winding directions of each winding on the third iron core column are the same.

[0013] In one embodiment, the number of turns of the corresponding windings on the first core post, the second core post, and the third core post are equal.

[0014] In one embodiment, the first and third windings on each core column have the same number of turns, and the fourth and fifth windings on each core column have the same number of turns.

[0015] This invention, by employing multiphase rectification and the connection relationship between the first, second, third, fourth, and fifth windings arranged on the first, second, and third iron core columns, can reduce the harmonic content of the input current, thereby reducing pollution to the power grid, improving the system's power factor, reducing reactive power consumption, and reducing the size and cost of the filter due to the reduced output current ripple. It can also reduce switching losses, improve the overall efficiency of the rectifier system, and will not exceed the reactive power and harmonic limits for industrial applications, thus reducing the impact on the power grid and harmonic interference to other electrical equipment. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a structural diagram of a multiphase transformer;

[0018] Figure 2 This is a schematic diagram showing the shift angle between the output windings of a multiphase transformer.

[0019] Figure 3 This is a diagram of the three-phase voltage waveforms;

[0020] Figure 4 This is a nine-phase voltage waveform diagram;

[0021] Figure 5 This is a waveform diagram of the fifteen-phase voltage.

[0022] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0024] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0025] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, if the word "and / or" appears throughout the text, it means including three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0026] This utility model proposes a multiphase transformer.

[0027] In the embodiments of this utility model, such as Figure 1 As shown, this multiphase transformer includes a first core post 10, a second core post 20, and a third core post 30. The first core post 10, the second core post 20, and the third core post 30 are each provided with a first winding, a second winding, a third winding, a fourth winding, and a fifth winding.

[0028] The first end of the first winding 11 on the first iron core column 10 is connected to the first end of the fifth winding 25 on the second iron core column 20 and the first end of the second winding 22 on the second iron core column 20, respectively. The second end of the second winding 22 on the second iron core column 20 is connected to the first end of the third winding 33 on the third iron core column 30 and the first end of the fourth winding 34 on the third iron core column 30, respectively. The second end of the fourth winding 34 on the third iron core column 30 is connected to the first end of the fifth winding 35 on the third iron core column 30.

[0029] The first end of the first winding on the second iron core column 20 is connected to the second end of the fifth winding 35 on the third iron core column 30 and the first end of the second winding 32 on the third iron core column 30, respectively. The second end of the second winding 32 on the third iron core column 30 is connected to the first end of the third winding 13 on the first iron core column 10 and the first end of the fourth winding 14 on the first iron core column 10, respectively. The second end of the fourth winding 14 on the first iron core column 10 is connected to the first end of the fifth winding 15 on the first iron core column 10.

[0030] The first end of the first winding 31 on the third iron core column 30 is connected to the second end of the fifth winding 15 on the first iron core column 10 and the first end of the second winding 12 on the first iron core column 10, respectively. The first end of the third winding 23 on the second iron core column 20 is connected to the second end of the second winding 12 on the first iron core column 10 and the first end of the fourth winding 24 on the second iron core column 20, respectively. The second end of the fourth winding 24 on the second iron core column 20 is connected to the second end of the fifth winding 25 on the second iron core column 20.

[0031] This invention, by employing multiphase rectification and the connection relationship between the first, second, third, fourth, and fifth windings arranged on the first iron core column 10, the second iron core column 20, and the third iron core column 30, can reduce the harmonic content of the input current, thereby reducing pollution to the power grid, improving the power factor of the system, reducing reactive power consumption, and reducing the size and cost of the filter due to the reduced output current ripple. It can also reduce switching losses, improve the overall efficiency of the rectifier system, and will not exceed the reactive power and harmonic limits of the power grid for industrial applications, thus reducing the impact on the power grid and harmonic interference to other electrical equipment.

[0032] The first iron core column 10, the second iron core column 20, and the third iron core column 30 are all provided with a sixth winding. The first end of the sixth winding 36 on the third iron core column 30 is connected to the second end of the fifth winding 25 and the second end of the fourth winding 24 on the second iron core column 20, respectively. The first end of the sixth winding 16 on the first iron core column 10 is connected to the second end of the fifth winding 35 and the second end of the fourth winding 34 on the third iron core column 30, respectively. The first end of the sixth winding 26 on the second iron core column 20 is connected to the second end of the fifth winding 15 and the second end of the fourth winding 14 on the first iron core column 10.

[0033] The output windings of the multiphase transformer are the first, third, and sixth windings on each core column.

[0034] like Figure 2 As shown, the phase shift angle between the output windings of the multiphase transformer is 20 degrees.

[0035] exist Figure 1 In the diagram, nodes (A, B, C) are the input terminals of the three-phase power frequency voltage, nodes (2, 8, 5) are the output terminals of the three-phase power frequency "main step-down phase", i.e., the output terminals of the lagging phase three-phase voltage, nodes (3, 6, 9) are the output terminals of the three-phase power frequency "lagging phase", and nodes (1, 4, 7) are the output terminals of the three-phase power frequency "leading phase", i.e., the output terminals of the leading phase three-phase voltage.

[0036] Figure 2In the middle, the line voltage difference vectors (1-4), (1-5), (1-6), (4-7), (4-8), (4-9), (7-1), (7-2), (7-3), etc., together with their inverse vectors (a total of 18 line voltage vectors), form a vector distribution with 20 degrees intervals within a 360-degree range.

[0037] By controlling the phase of current or voltage through the coil section of an autotransformer, the motor speed can be adjusted, the power factor improved, or voltage regulated. This embodiment can achieve a 9-phase, 18-pulse output. Ideally, the product of the phase shift angle 'a' between the output windings and the final pulse count 'p' equals 360 degrees. That is, axp = 360. For example, if the phase shift angle between the output windings is 'a' = 20°, the pulse count 'p' of the rectifier can be obtained from p = 360 / 20 = 18.

[0038] The winding directions of each winding on the first iron core column 10 are the same, the winding directions of each winding on the second iron core column 20 are the same, and the winding directions of each winding on the third iron core column 30 are the same.

[0039] In a multi-column core structure, ensuring that the windings on each column are wound in the same direction is crucial for the transformer's proper operation and improves its efficiency. Consistent winding direction ensures that the magnetic field within the core columns is oriented in the same direction. The magnetic field generated by the windings on each column will correctly superimpose with the magnetic fields on the other columns, thus forming the desired magnetic field distribution. If the winding directions are inconsistent, the magnetic fields may cancel each other out, causing the equipment to malfunction.

[0040] Multiple windings on a core column are used for alternating current of different phases. Windings with the same winding direction ensure that the magnetic field generated on each core column is in the correct direction, allowing the rotating magnetic field of the motor to drive the rotor stably and effectively. Inconsistent winding directions on different columns can affect the phase sequence, potentially leading to motor failure or unstable speed. Having multiple windings with the same direction ensures that the propagation direction of electromagnetic waves is consistent, helping to reduce electromagnetic interference caused by phase misalignment. If the winding directions are different, it may lead to mutual interference and increased losses between windings. A uniform winding direction helps improve the conversion efficiency of electromagnetic energy. In equipment such as motors or transformers, a uniform winding direction can maximize the utilization of the magnetic field, reduce losses, and improve the overall efficiency of the equipment. The winding directions of multiple core columns in a transformer also need to be the same to ensure stable transmission of magnetic flux, avoid unnecessary magnetic field cancellation, and improve transformer efficiency.

[0041] The number of turns of the corresponding windings on the first core post 10, the second core post 20, and the third core post 30 are equal. The number of turns of the first winding and the third winding on each core post are the same, and the number of turns of the fourth winding and the fifth winding on each core post are the same.

[0042] The equal number of turns in the corresponding windings on the first core column 10, the second core column 20, and the third core column 30 ensures that the magnetic field strength generated on each core column is the same. Since the basic principle of electromagnetic induction is that the number of turns is proportional to the magnetic field strength, equal turns ensure that the magnetic flux generated by each core column is equal, thus guaranteeing a uniform and symmetrical magnetic field distribution throughout the equipment. Unequal turns in different core columns will lead to uneven magnetic field distribution, potentially causing magnetic flux imbalance, which in turn affects the operating efficiency of the equipment or causes localized overheating and losses. In transformer equipment, each core column typically corresponds to a different phase (e.g., different phases of a three-phase current). Ensuring that the number of turns in the windings on each column is equal ensures that the contribution of the current in each phase to the magnetic circuit is equal, thus guaranteeing phase balance of the equipment. Unbalanced phases may cause the equipment to malfunction or even be damaged.

[0043] A design with an equal number of turns ensures maximum energy transfer efficiency and avoids energy waste caused by differences in the number of turns. For example, in transformers, an equal number of turns guarantees maximum utilization of magnetic flux, thereby improving the efficiency of electrical energy conversion. Windings with an equal number of turns enable transformer equipment to exhibit better load capacity and stability under load variations. Consistent turns in the windings of each phase ensure even distribution of load current, reducing the risks associated with unbalanced loads during equipment operation; uneven magnetic flux can cause fluctuations in current and magnetic fields within the equipment, generating harmonics and noise. Windings with an equal number of turns ensure uniform magnetic field distribution, effectively reducing harmonic interference and mechanical noise.

[0044] like Figure 3 , Figure 4 , Figure 5 As shown in the diagram, each curve represents a phase. The more output windings a transformer has, the smaller the voltage variation between waveforms, and thus the smaller the ripple. In a three-phase power system, the current load between each phase is balanced. However, in a nine-phase or fifteen-phase system, due to the finer phase differences, the system can distribute the load more evenly, reducing equipment vibration and losses, and extending equipment lifespan. More phases can improve the redundancy and stability of the power system. Even if one phase fails, the system can still resume operation in a shorter time, unlike a three-phase system which would cause a power outage. Nine-phase and fifteen-phase systems are commonly used in high-performance, high-reliability power drive systems, such as large motor drives, charging rectifier cabinets, and large substations.

[0045] The above description is only an optional embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A multiphase transformer, characterized in that, It includes a first iron core post, a second iron core post, and a third iron core post, and each of the first iron core post, the second iron core post, and the third iron core post is provided with a first winding, a second winding, a third winding, a fourth winding, and a fifth winding; The first end of the first winding on the first iron core column is connected to the first end of the fifth winding on the second iron core column and the first end of the second winding on the second iron core column, respectively. The second end of the second winding on the second iron core column is connected to the first end of the third winding on the third iron core column and the first end of the fourth winding on the third iron core column, respectively. The second end of the fourth winding on the third iron core column is connected to the first end of the fifth winding on the third iron core column. The first end of the first winding on the second iron core column is connected to the second end of the fifth winding on the third iron core column and the first end of the second winding on the third iron core column, respectively. The second end of the second winding on the third iron core column is connected to the first end of the third winding on the first iron core column and the first end of the fourth winding on the first iron core column, respectively. The second end of the fourth winding on the first iron core column is connected to the first end of the fifth winding on the first iron core column. The first end of the first winding on the third iron core column is connected to the second end of the fifth winding on the first iron core column and the first end of the second winding on the first iron core column, respectively. The first end of the third winding on the second iron core column is connected to the second end of the second winding on the first iron core column and the first end of the fourth winding on the second iron core column, respectively. The second end of the fourth winding on the second iron core column is connected to the second end of the fifth winding on the second iron core column.

2. The multiphase transformer as described in claim 1, characterized in that, A sixth winding is provided on the first iron core column, the second iron core column, and the third iron core column. The first end of the sixth winding on the third iron core column is connected to the second end of the fifth winding on the second iron core column and the second end of the fourth winding on the second iron core column, respectively. The first end of the sixth winding on the first iron core column is connected to the second end of the fifth winding on the third iron core column and the second end of the fourth winding on the third iron core column, respectively. The first end of the sixth winding on the second iron core column is connected to the second end of the fifth winding on the first iron core column and the second end of the fourth winding on the first iron core column.

3. The multiphase transformer as described in claim 2, characterized in that, The output windings of the multiphase transformer are the first, third, and sixth windings on each core column.

4. The multiphase transformer as described in claim 3, characterized in that, The phase shift angle between the output windings of the multiphase transformer is 20 degrees.

5. The multiphase transformer as described in claim 1, characterized in that, The winding directions of each winding on the first iron core column are the same, the winding directions of each winding on the second iron core column are the same, and the winding directions of each winding on the third iron core column are the same.

6. The multiphase transformer as described in claim 1, characterized in that, The number of turns of the corresponding windings on the first iron core column, the second iron core column, and the third iron core column are equal.

7. The multiphase transformer as described in claim 1, characterized in that, The number of turns in the first and third windings on each core column is the same, and the number of turns in the fourth and fifth windings on each core column is the same.

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