A wire wound balancing reactor, manufacturing method and application

Abstract

The application provides a wire-wound balanced reactor, a manufacturing method and application, which comprises a core, a first fixing assembly and a second fixing assembly are arranged on the core, a lead copper bar is connected between the first fixing assembly and the second fixing assembly, and a combined coil is connected to the lead copper bar; the combined coil comprises a plurality of coil groups, the coil groups are staggered and wound on the core, and tail ends and initial sections of the coil groups are connected to the lead copper bar respectively. The balanced reactor realizes partial offset of a magnetic field by means of the staggered and wound coil groups and a reverse winding technology, effectively balances currents at positive star and reverse star neutral points, significantly reduces current harmonics, reduces electromagnetic interference, and when a large current is needed, the cross-sectional area of the core does not need to be adjusted, the size of the balanced reactor is prevented from being increased, the installation of other components is prevented from being affected, the installation difficulty is reduced, and the production cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of transformer equipment technology, specifically to a wire-wound balancing reactor, its manufacturing method, and its application. Background Technology

[0002] In existing double-anti-star converter transformers, the balancing reactor plays a core role. Its function is to balance the output current of the two sets of anti-phase parallel six-pulse rectifier bridges, suppress circulating current, and ensure the stability and balance of DC side current. The balancing reactor has a structure of "U"-shaped iron core and through winding; since the through winding is made of copper busbar.

[0003] Currently, the number of turns in balancing reactors is usually set to 1 turn. When encountering a higher rated DC output voltage, in order to meet the strict requirements of the system for the balancing inductance, the required inductance value of the balancing reactor must be increased. Under the constraint of 1 turn, a "U"-shaped iron core with a cross-sectional area is forced to be selected, which directly leads to the volume and weight of the balancing reactor body expanding many times. It is forced to be placed in the relatively compact overall structural frame of the converter transformer, which will occupy the space of the main transformer body, heat dissipation channel or other auxiliary components, affecting the installation of other components. At the same time, it will also cause the balancing reactor to be out of proportion with the main transformer and other components in terms of physical size, making the overall structural layout appear bloated and uncoordinated, making structural arrangement difficult, and increasing production costs. Summary of the Invention

[0004] To address the problem that using a single-turn balancing reactor in environments with high output voltage necessitates increasing the core volume, leading to transformer structural inconsistencies and installation difficulties, this invention provides a wire-wound balancing reactor, its manufacturing method, and its application.

[0005] To achieve the above objectives, the present invention provides the following technical solution: This invention proposes a wire-wound balanced reactor, including an iron core, on which a first fixing component and a second fixing component are disposed, and a copper busbar is connected between the first fixing component and the second fixing component, and a combined coil is connected to the copper busbar. The combined coil includes multiple coil groups, which are wound alternately around the iron core, and the tail end and head end of each coil group are respectively connected to the lead copper busbar.

[0006] Preferably, the combined coil includes a primary coil group and a secondary coil group, which are alternately wound on the iron core at a position between the first fixing component and the second fixing component; Furthermore, the tail end of the primary coil group and the head end of the secondary coil group are located on the same side of the iron core.

[0007] Preferably, the primary coil group and the secondary coil group are wound in opposite directions on the iron core.

[0008] Preferably, the core comprises a plurality of silicon steel sheets, which are stacked to form a square ring. The first fixing component is disposed on one side of the square ring, and the second fixing component is disposed on the side of the square ring opposite to the first fixing component.

[0009] Preferably, the first fixing component includes two first clamping plates, which are clamped on one side of the square ring. A first connecting plate is connected to the bottom end face of one of the first clamping plates. The first connecting plate is connected to the fixing plate, and the fixing plate is connected to the upper end of the lead copper busbar.

[0010] Preferably, the second fixing component includes two second clamping plates, which are clamped on one side of the square ring opposite to the first clamping plate, and the second clamping plates are parallel to the first clamping plate. A second connecting plate is connected to the top end face of one of the second clamping plates. The second connecting plate is connected to a support platform, which is supported on the bottom end face of the copper busbar.

[0011] Preferably, the lead copper busbar includes a first head end lead copper busbar, a second head end lead copper busbar, and a tail end lead copper busbar arranged side by side; The second lead-out copper busbar is disposed between the first lead-out copper busbar and the tail lead-out copper busbar; The first end of the primary coil group is connected to the first lead-out copper busbar, the first end of the secondary coil group is connected to the second lead-out copper busbar, and the tail end of the primary coil group is connected to the tail end of the secondary coil group and the tail end lead-out copper busbar.

[0012] Preferably, a yoke for connecting the transformer frame is installed on the square ring.

[0013] This invention proposes a method for manufacturing a wire-wound balancing reactor, which includes the following steps: Four single-phase iron cores are made. Two of the iron cores are selected and a combined coil is wound on them. The other two iron cores are connected to the iron cores with the combined coils to form a square ring, and the two iron cores with the combined coils are parallel to each other. A first fixing component is installed on one of the iron cores without the combined coil, and a second fixing component is installed on the other iron core without the combined coil. A lead copper busbar is connected between the first fixing component and the second fixing component. The lead copper busbar is connected to the combined coil, as well as the neutral point of the positive star and the neutral point of the negative star in the rectifier transformer.

[0014] This invention proposes the application of the above-mentioned wire-wound balanced reactor in a double-reverse star converter transformer.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention proposes a wire-wound balancing reactor. This balancing reactor, through interleaved winding coils combined with reverse winding technology, achieves partial cancellation of the magnetic field, reduces leakage flux, effectively balances the current at the neutral points of the positive and negative stars, significantly reduces current harmonics, thereby greatly improving power quality and reducing electromagnetic interference. Simultaneously, when large currents are required, the cross-sectional area of ​​the iron core does not need to be adjusted, avoiding an increase in the reactor's size that could affect the installation of other components, thus reducing installation difficulty and production costs. The direct connection of the lead copper busbars to the neutral point of the rectifier transformer optimizes the current path, reduces energy loss, and improves the overall system efficiency. The connection of both the tail and head ends of the coil group to the lead copper busbars simplifies the wiring structure, making installation and maintenance more convenient. The compact structure of the reactor and the fixed components on the iron core ensure the stability and reliability of the coils, effectively extending the service life of the equipment.

[0016] Furthermore, this balancing reactor employs a primary coil group and a secondary coil group that are alternately wound on the iron core in opposite directions, which optimizes the current path. By setting up the primary and secondary coil groups, the volume of the iron core is avoided during manufacturing due to the large current required, thus maintaining the compact structure of the reactor, reducing production costs, and improving the ease of installation.

[0017] Furthermore, this balancing reactor features parallel lead-out copper busbars at the beginning and end. The primary and secondary coil groups are connected to the positive and negative neutral points of the rectifier transformer via independent lead-out copper busbars, significantly simplifying the wiring structure and effectively reducing conductor resistance loss and stray inductance.

[0018] Furthermore, an iron yoke is installed on the iron core of this balancing reactor, which stabilizes the iron core within the transformer frame, thereby improving installation stability. Attached Figure Description

[0019] Figure 1 This invention provides a front view structural schematic diagram of a wire-wound balancing reactor; Figure 2 This is a side view cross-sectional structural diagram of a wire-wound balancing reactor provided by the present invention; Figure 3 This is a schematic diagram of the sectional structure of a wire-wound balanced reactor provided by the present invention; Figure 4A schematic diagram illustrating the wiring principle of a wire-wound balancing reactor and a current transformer provided by the present invention; In the attached diagram: 1. Iron core; 2. Combined coil; 21. Primary coil group; 22. Secondary coil group; 3. Lead copper busbar; 31. First lead-out copper busbar; 32. Second lead-out copper busbar; 33. Tail lead-out copper busbar; 4. First connecting plate; 12. Second connecting plate; 5. First fixing plate; 6. First clamping plate; 7. First fixing ring; 8. Second fixing ring; 9. Second clamping plate; 10. Support plate; 11. Mounting base plate; 12. Second connecting plate; 13. Support platform; 14. Yoke. Detailed Implementation

[0020] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0021] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0023] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0025] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0026] This invention proposes a wire-wound balancing reactor, such as... Figures 1-3 As shown, the transformer includes an iron core 1, on which a first fixing component and a second fixing component are mounted. A copper busbar 3 connects the first fixing component and the second fixing component, and a combined coil 2 is connected to the copper busbar 3. The copper busbar 3 is connected to the neutral points of the positive and negative stars in the rectifier transformer, respectively. The combined coil 2 includes multiple coil groups, which are interleaved and wound around the iron core 1. The tail and head ends of the multiple coil groups are connected to the copper busbar 3, respectively. Specifically, the combined coil 2 includes a primary coil group 21 and a secondary coil group 22, which are interleaved and wound around the iron core 1 between the first fixing component and the second fixing component. The tail end of the primary coil group 21 and the head end of the secondary coil group 22 are located on the same side of the iron core 1, and the winding directions of the primary coil group 21 and the secondary coil group 22 on the iron core 1 are opposite. 2. The coils are alternately wound in opposite directions around the core 1 and connected electrically via copper busbars 3. This creates a dynamic complementary effect in the core 1 by the magnetic flux generated by the primary coil group 21 and the secondary coil group 22. Even if the current increases, there is no need to increase the cross-sectional area of ​​the core, resulting in a smaller balancing reactor. This reduces the overall manufacturing cost of the balancing reactor while ensuring its performance. It solves the problem of the large size of the balancing reactor due to the high rated DC output voltage of the double-anti-star converter transformer and significantly reduces the total cost of the balancing reactor. It can also be flexibly matched with rectifier systems of different voltage levels. The modular winding structure facilitates capacity expansion. When the primary coil group 21 is energized, the positive magnetic flux it generates and the reverse magnetic flux generated by the reverse winding of the secondary coil group 22 form a vector superposition in the closed magnetic circuit of the core 1, effectively canceling the DC bias phenomenon commonly found in traditional reactors.

[0027] like Figures 1-3As shown, the core 1 includes multiple silicon steel sheets, which are stacked to form a square ring. A first fixing component is provided on one side of the square ring, and a yoke 14 for connecting to the transformer frame is installed on the square ring. The yoke 14 stabilizes the core 1 within the transformer frame, improving installation stability. A second fixing component is provided on the side of the square ring opposite to the first fixing component. The first fixing component includes two first clamping plates 6, which are clamped on one side of the square ring. A first connecting plate 4 is connected to the bottom end face of one of the first clamping plates 6, and the first connecting plate 4 is connected to a fixing plate 5. The fixing plate 5 is connected to the upper end of the lead copper busbar 3. The second fixing component includes two second clamping plates 9, which are clamped on the side of the square ring opposite to the first clamping plate 6. The second clamping plates 9 are parallel to the first clamping plates 6. A first connecting plate 4 is connected to the top end face of one of the second clamping plates 9, and the second connecting plate 12 is connected to a support platform 13. The support platform 13 is supported on the bottom end face of the lead copper busbar 3.

[0028] like Figures 2-3 As shown, the lead copper busbar 3 includes a first head-out copper busbar 31, a second head-out copper busbar 32, and a tail-out copper busbar 33 arranged side by side; the second head-out copper busbar 32 is located between the first head-out copper busbar 31 and the tail-out copper busbar 33; the head end of the primary coil group 21 is connected to the first head-out copper busbar 31, the head end of the secondary coil group 22 is connected to the second head-out copper busbar 32, and the tail end of the primary coil group 21 is connected to the tail end of the secondary coil group 22 and the tail-out copper busbar 33. That is, the head end o1 of the primary coil group 21 is connected to the first head-out copper busbar 31, and the head end o2 of the secondary coil group 22 is connected to the second head-out copper busbar 32. The tail ends m1 of the primary coil group 21 and m2 of the secondary coil group 22 are connected to the tail-out copper busbar 33, thus completing the fabrication of the entire wire-wound balanced reactor. Finally, the neutral points of the positive and negative stars in the rectifier transformer are connected to the first lead-out copper busbar 31 and the second lead-out copper busbar 32, respectively. The primary coil group 21 is connected to the neutral points of the positive and negative stars of the rectifier transformer through the independent first lead-out copper busbar 31, and the secondary coil group 22 is connected to the neutral points of the positive and negative stars of the rectifier transformer through the independent second lead-out copper busbar 32. Combined with the centralized lead-out method of the tail lead-out copper busbar 33, the wiring structure is significantly simplified and the current path is shortened, effectively reducing wire resistance loss and stray inductance. The alternating magnetic field generated by the primary coil group 21 and the secondary coil group 22 forms a dynamic cancellation effect in the iron core, which greatly reduces the electromagnetic interference of leakage flux to surrounding equipment and improves the utilization rate of the iron core magnetic circuit. The independent connection of the first lead-out copper busbar 31 and the second lead-out copper busbar 32 to the neutral point can accurately balance the positive and negative star current waveforms. The phase difference compensation mechanism effectively suppresses the current harmonic distortion rate, so that the output power quality meets the requirements of high-precision applications.

[0029] The primary coil group 21 and secondary coil group 22 of this balancing reactor are staggered and tightly coupled, resulting in a compact structure. Simultaneously, the primary coil group 21 and secondary coil group 22 are cold-pressed to the lead copper busbar 3, and then connected to the transformer body. The overall lead structure is simple, mature, and easy to operate. Compared with the traditional "U"-shaped through-copper busbar structure, less silicon steel sheet is used, and the balancing reactor is smaller. This reduces the overall manufacturing cost of the balancing reactor while ensuring its performance. It solves the problem of the large size of the balancing reactor due to the high DC rated output voltage of the double-anti-star transformer, and also significantly reduces the total cost of the balancing reactor.

[0030] This invention proposes a method for manufacturing a wire-wound balancing reactor, used to manufacture a wire-wound balancing reactor according to any one of the above-mentioned methods, comprising the following steps: Make four single-phase iron cores 1, select two of the iron cores 1, and wind a combined coil 2 on them. Connect the other two iron cores 1 with the iron cores 1 with the combined coil 2 to form a square ring, and make the two iron cores 1 with the combined coil 2 parallel to each other. A first fixing component is installed on one iron core 1 without the combined coil 2, and a second fixing component is installed on the other iron core 1 without the combined coil 2. A lead copper busbar 3 is connected between the first fixing component and the second fixing component. The lead copper busbar 3 is connected to the combined coil 2, as well as the neutral point of the positive star and the neutral point of the negative star in the rectifier transformer.

[0031] Specifically, the current and voltage of the primary coil group 21 and the secondary coil group 22 are determined based on the voltage and current on the valve side of the rectifier transformer. The cross-sectional area and diameter of the iron core are adjusted by adjusting the number of turns of the primary coil group 21 and the secondary coil group 22. The appropriate paper-insulated flat copper wire size and the number of parallel wires are selected, and finally the geometric dimensions such as the diameter, window height and width of the iron core 1 are determined.

[0032] Four single-phase iron cores 1 are manufactured according to the selected geometric dimensions of the iron core 1; a combined coil 2 is wound using paper-insulated flat copper wire, that is, a primary coil group 21 and a secondary coil group 22 are wound using paper-insulated flat copper wire to form a combined coil 2, and the primary coil group 21 and the secondary coil group 22 are wound alternately. At the same time, the tail end of the primary coil group 21 and the head end of the secondary coil group 22 are located on the same side, that is, the head and tail of the primary coil group 21 and the secondary coil group 22 in the same combined coil 2 are opposite. Two iron cores 1 are selected, and the wound combined coil 2 is sleeved on the iron core 1. One combined coil 2 is sleeved on one iron core 1. The other two iron cores are connected to the iron cores 1 on which the combined coil 2 is sleeved to form a square ring, and the two iron cores 1 on which the combined coil 2 is sleeved are parallel to each other. First clamping plates 6 are installed on the front and rear end faces of one iron core 1 without the combined coil 2. The first clamping plates 6 are parallel to the iron core 1. A first connecting plate 4 is connected to the bottom end face of one of the first clamping plates 6. The first connecting plate 4 is connected to a fixing plate 5. The fixing plate 5 is connected to the upper end of the lead copper busbar 3. That is, the fixing plate 5 is connected to the upper end of the first lead copper busbar 31, the second lead copper busbar 32, and the tail lead copper busbar 33. Second clamping plates 9 are installed on the front and rear end faces of the other iron core 1 without the combined coil 2. The two second clamping plates 9 are clamped on the side of the square ring opposite to the first clamping plate 6. The second clamping plates 9 are parallel to the first clamping plates 6. A second connecting plate 12 is connected to the top end face of one of the second clamping plates 9. The second connecting plate 12 is connected to a support platform 13, which is supported on the bottom end face of the lead copper busbar 3. That is, the lower ends of the first lead copper busbar 31, the second lead copper busbar 32, and the tail lead copper busbar 33 are installed on the support platform 13. The first end o1 of the primary coil group 21 is connected to the first lead copper busbar 31, the first end o2 of the secondary coil group 22 is connected to the second lead copper busbar 32, and the tail end m1 of the primary coil group 21 and the tail end m2 of the secondary coil group 22 are connected to the tail lead copper busbar 33, thus completing the fabrication of the entire wire-wound balanced reactor. Finally, the neutral points of the positive star and the negative star in the rectifier transformer are connected to the first lead copper busbar 31 and the second lead copper busbar 32, respectively. Figure 4 As shown, a1, b1, c1 and a4, b4, c4 are the two star-connected 3-phase output terminals with opposite points on the double-reverse-star rectifier transformer. o1 and o2 are its neutral points. The first end o1 of the primary coil group 21 and the last end m1 of the secondary coil group 22 on the balancing reactor are connected to the neutral point o1 of the positive-star rectifier transformer. In actual installation, the first end o1 of the primary coil group 21 is connected to the positive-star neutral point o1, and the last end m1 of the primary coil group 21 is connected to the corresponding terminal of the external rectifier cabinet. The first end o2 and the last end m2 of the secondary coil group 22 on the balancing reactor are connected to the neutral point o2 of the reverse-star rectifier transformer. That is, the first end o2 of the secondary coil group 22 is connected to the reverse-star neutral point o2, and the last end m2 of the secondary coil group 22 is connected to the corresponding terminal of the external rectifier cabinet. Finally, the electrical wiring of the rectifier transformer and the balancing reactor is completed.

[0033] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the scope of the invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0034] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be appropriately combined to form other embodiments that can be understood by those skilled in the art. The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A wire-wound balancing reactor, characterized in that, Includes an iron core (1), on which a first fixing component and a second fixing component are provided, and a lead copper busbar (3) is connected between the first fixing component and the second fixing component, and a combined coil (2) is connected to the lead copper busbar (3). The combined coil (2) includes multiple coil groups, which are interleaved and wound around the iron core (1). The tail end and the head end of the multiple coil groups are respectively connected to the lead copper busbar (3). The combined coil (2) includes a primary coil group (21) and a secondary coil group (22), which are alternately wound on the iron core (1) at a position between the first fixing component and the second fixing component; Furthermore, the tail end of the primary coil group (21) and the head end of the secondary coil group (22) are located on the same side of the iron core (1); The core (1) includes multiple silicon steel sheets, which are stacked to form a square ring. The first fixing component is provided on one side of the square ring, and the second fixing component is provided on the side of the square ring opposite to the first fixing component. The first fixing component includes two first clamping plates (6), which are clamped on one side of the square ring. A first connecting plate (4) is connected to the bottom end face of one of the first clamping plates (6). The first connecting plate (4) is connected to a fixing plate (5), and the fixing plate (5) is connected to the upper end of the lead copper busbar (3). The second fixing component includes two second clamping plates (9), which are clamped on one side of the square ring opposite to the first clamping plate (6), and the second clamping plates (9) are parallel to the first clamping plate (6); A second connecting plate (12) is connected to the top end face of one of the second clamping plates (9), and the second connecting plate (12) is connected to a support platform (13), which is supported on the bottom end face of the lead copper busbar (3); The lead copper busbar (3) includes a first head end lead copper busbar (31), a second head end lead copper busbar (32) and a tail end lead copper busbar (33) arranged side by side. The second lead-out copper busbar (32) is disposed between the first lead-out copper busbar (31) and the tail lead-out copper busbar (33); The first end of the primary coil group (21) is connected to the first lead-out copper busbar (31), the first end of the secondary coil group (22) is connected to the second lead-out copper busbar (32), and the tail ends of the primary coil group (21) and the secondary coil group (22) are both connected to the tail lead-out copper busbar (33). The primary coil group (21) and the secondary coil group (22) are wound in opposite directions on the iron core (1).

2. The wire-wound balanced reactor according to claim 1, characterized in that, The square ring is fitted with a yoke (14) for connecting the transformer frame.

3. A method for manufacturing a wire-wound balancing reactor, used to manufacture a wire-wound balancing reactor as described in any one of claims 1 to 2, characterized in that, Includes the following steps: Make four single-phase iron cores (1), select two of the iron cores (1), and wrap a combined coil (2) on them. Connect the other two iron cores (1) with the iron cores (1) with the combined coil (2) to form a square ring, and the two iron cores (1) with the combined coil (2) are parallel to each other. A first fixing component is installed on one of the iron cores (1) without the combined coil (2) and a second fixing component is installed on the other iron core (1) without the combined coil (2). A lead bus (3) is connected between the first fixing component and the second fixing component. The lead bus (3) connects the combined coil (2) and the neutral point of the positive star and the neutral point of the negative star in the rectifier transformer.

4. The application of a wire-wound balancing reactor as described in any one of claims 1 to 2 in a double-reverse star converter transformer.

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