Transformer coil with low eddy current loss and transformer
By designing the coil structure with a specific ratio and the transformer coil with a tilt part at the end, the problem of major vortex losses in the existing technology is solved, and the low vortex loss and high stability of the transformer are achieved.
Patent Information
- Application Number
- CN202420297847.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-18
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-02-18
AI Technical Summary
The existing transformer coils cause large eddy current losses in the non-uniform magnetic field, which affects the efficiency and stability of the transformer.
Design a transformer coil with low vortex losses, which adopts a combined structure of low-pressure coil and high-pressure coil. -1.8, and the tilt part is set at the end of the coil to reduce the vortex losses caused by the magnetic field.
By optimizing the coil structure, reducing the vortex losses generated in different parts of the magnetic field in different parts, reducing the temperature rise of the transformer, and improving the stability of the transformer and the service life.
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Figure CN222421584U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of transformers, and in particular to a transformer coil and a transformer with low eddy current loss. Background Art
[0002] When a conductor moves in a non-uniform magnetic field or is in a magnetic field that changes with time, the energy loss caused by the induced current in the conductor is called eddy current loss. The multiple closed current lines formed inside the conductor are called eddy currents. Due to the thermal effect of the current, eddy currents can cause the conductor to heat up and consume energy, so eddy currents are sometimes harmful.
[0003] In the related art, the transformer coil includes a plurality of wires combined into one body and an insulating layer covering the outer surface thereof, and an insulating paper layer is arranged between two adjacent wires. That is, a single wire that originally needs to be covered with an insulating layer before being combined into a group is changed into a parallel wire group composed of several bare wires, an insulating paper layer is arranged between each two adjacent wires, and then the outer surface of the wire group is covered with an insulating layer that meets the requirements, so that the overall size of the wire group is greatly reduced, and the space occupied by the coil can be reduced after winding, that is, the material consumption of the transformer can be greatly reduced, and the production cost of the transformer can be reduced.
[0004] The above technical solution still has the following defects: although it can reduce material consumption, the reduction of eddy current loss is limited. Utility Model Content
[0005] In order to reduce eddy current loss, the present application provides a transformer coil and a transformer with low eddy current loss.
[0006] In a first aspect, the present application provides a transformer coil with low eddy current loss, which adopts the following technical solution:
[0007] A transformer coil with low eddy current loss comprises a low voltage coil and a high voltage coil arranged outside the low voltage coil, wherein the upper ends of the low voltage coil and the high voltage coil are arranged as a first coil, the middle section is arranged as a second coil, and the lower end is arranged as a third coil, the ratio of the axial width to the radial thickness of the cross section of the second coil is in the range of 5-8, the ratio of the axial width to the radial thickness of the first coil and the third coil is in the range of 1.4-1.8, and the ends of the first coil and the third coil are arranged with inclined portions.
[0008] By adopting the above technical solution, the eddy current loss caused by the leakage magnetic field in the low-voltage coil and the high-voltage coil can be reduced. In the middle position of the leakage magnetic field, the eddy current loss is mainly generated by the axial component of the leakage magnetic field, and the axial width and radial thickness of the second coil section are relatively large, which can reduce the eddy current loss generated by the leakage magnetic field in the second coil; at the two ends of the leakage magnetic field, the eddy current loss is mainly generated by the radial component of the leakage magnetic field, and the axial width and radial thickness of the first coil and the third coil are relatively small, which can reduce the eddy current loss generated by the leakage magnetic field in the first coil and the third coil. At the same time, the inclined portion can reduce the eddy current loss caused by the leakage magnetic field, reduce the eddy current loss, and reduce the heat generated by the conductor, thereby enhancing the stability of the transformer.
[0009] Optionally, the inclined surface of the inclined portion is configured as a stepped surface.
[0010] By adopting the above technical solution, the eddy current loss affecting the coil of the transformer increases according to the size of the vector of the leakage magnetic flux entering the coil wire from the coil end in the vertical direction. In this case, since the inclined portion is provided at the end of the coil, the level of the leakage magnetic flux affecting the coil end wire is reduced.
[0011] Optionally, insulating material is disposed in the inclined portion.
[0012] By adopting the above technical solution, the performance and quality of the insulating material directly affect the reliability of the transformer operation and the service life of the transformer. The insulating material not only plays a role in heat dissipation and cooling, but also plays a role in supporting and fixing, so that the shapes of the first coil and the second coil can be maintained.
[0013] Optionally, the axial width of the second coil cross section is 2-2.5 times the axial width of the first coil cross section and the third coil cross section, and the radial thickness of the second coil cross section is 0.3-0.5 times the radial thickness of the first coil cross section and the third coil cross section.
[0014] By adopting the above technical solution, the radial thickness of the second coil cross section is small, and the axial widths of the first coil and the third coil cross sections are small, thereby reducing eddy current losses caused by the leakage magnetic field.
[0015] Optionally, the first coil and the third coil include a plurality of sub-coils arranged in the axial direction, and a ratio of an axial width to a radial thickness of a cross section of the sub-coils gradually decreases in a direction away from the second coil.
[0016] By adopting the above technical solution, the axial width of the cross section of the first coil and the third coil is gradually reduced, so that the increase of the radial thickness of the cross section of the first coil and the third coil will not significantly increase the eddy current loss.
[0017] Optionally, an insulating cylinder is connected to a side of the low-voltage coil close to the high-voltage coil.
[0018] By adopting the above technical solution, it is possible to avoid direct contact between the low-voltage coil and the high-voltage coil, thereby achieving the effect of voltage isolation. The working principle of the transformer is to amplify or reduce the voltage through mutual inductance, thereby realizing power conversion. The role of the insulating cylinder is reflected in its ability to isolate the different electric potentials inside the transformer, ensure the safe and stable operation of the system, and prevent the current from crossing different circuits and causing dangers such as short circuits. In the power system, the transformer insulating cylinder is one of the important components to ensure system safety.
[0019] Optionally, a heat dissipation cavity is provided between the insulating cylinder and the high-voltage coil.
[0020] By adopting the above technical solution, the flow space for heat dissipation is enhanced. When the transformer is running, heat is generated. The heat comes from two aspects: one is iron loss, that is, the heat generated by the loss of eddy current in the transformer core; the other is the heat generated by the load current flowing through the transformer winding. This heat is proportional to the square of the current. The generated heat must be dissipated in time, otherwise it will damage the transformer. The heat dissipation cavity facilitates the conduction of the heat generated by the coil to protect the transformer.
[0021] Optionally, a limiting block is connected between the insulating cylinder and the high-voltage coil.
[0022] By adopting the above technical solution, the limit block can limit the high-voltage coil, avoid direct contact between the high-voltage coil and the insulating cylinder, and ensure the working performance of the insulating cylinder.
[0023] In a second aspect, the present application provides a transformer, which adopts the following technical solution:
[0024] A transformer comprises the above-mentioned transformer coil with low eddy current loss.
[0025] By adopting the above technical solution, eddy current loss is small, so that the temperature rise of the transformer is reduced, the components in the transformer are protected, and the service life of the transformer is increased.
[0026] In summary, this application has the following beneficial effects:
[0027] By providing the first coil, the second coil and the third coil, the eddy current loss generated in the second coil by the axial component of the leakage magnetic field can be reduced, and the eddy current loss generated in the first coil and the third coil by the radial component of the leakage magnetic field can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Figure 1 is a cross-sectional view of the transformer of Example 1 of the present application;
[0029] Figure 2 is a cross-sectional view of a low-voltage coil according to Embodiment 1 of the present application;
[0030] Figure 3 It is a cross-sectional view of the first coil of Example 2 of the present application.
[0031] Explanation of the reference numerals: 1. low-voltage coil; 11. first coil; 111. inclined portion; 112. insulating material; 113. sub-coil; 12. second coil; 13. third coil; 2. high-voltage coil; 3. insulating cylinder; 4. heat dissipation cavity; 5. limit block; 6. iron core. DETAILED DESCRIPTION
[0032] The following is combined with Figure 1-3 This application is described in further detail.
[0033] Embodiment 1:
[0034] Embodiment 1 of the present application discloses a transformer coil with low eddy current loss.
[0035] Reference Figure 1 The transformer includes an iron core and a transformer coil with low eddy current loss installed on the iron core. The transformer coil with low eddy current loss includes a low-voltage coil 1 and a high-voltage coil 2. The high-voltage coil 2 is arranged on the outside of the low-voltage coil 1 for insulation treatment. A heat dissipation cavity 4 is arranged between the low-voltage coil 1 and the high-voltage coil 2 to facilitate heat dissipation. An insulating cylinder 3 is fixedly connected to the side of the low-voltage coil 1 close to the high-voltage coil 2. The insulating cylinder 3 is a tubular part made of cardboard or hardboard, and the surface of the insulating cylinder is smooth and free of sand holes. A limiting block 5 is fixedly connected between the insulating cylinder 3 and the high-voltage coil 2 to prevent the low-voltage coil 1 and the high-voltage coil 2 from direct contact, thereby achieving an insulation effect.
[0036] Reference Figure 1 and Figure 2 The low-voltage coil 1 and the high-voltage coil 2 both include a first coil 11, a second coil 12 and a third coil 13. The first coil 11 is conductively connected to the second coil 12, the second coil 12 is conductively connected to the third coil 13, and the second coil 12 is disposed between the first coil 11 and the third coil 13. a is the axial width of the coil cross section, and b is the radial thickness of the coil cross section. The ratio of the axial width to the radial thickness of the cross section of the second coil 12 is greater than the ratio of the axial width to the radial thickness of the first coil 11 and the third coil 13.
[0037] The ratio a / b of the axial width and radial thickness of the cross section of the second coil 12 is 5-8, and the ratio a / b of the axial width and radial thickness of the cross sections of the first coil 11 and the third coil 13 is 1.4-1.8. The axial width of the cross section of the second coil 12 is 2-2.5 times the axial width of the cross sections of the first coil 11 and the third coil 13, and the radial thickness of the cross section of the second coil 12 is 0.3-0.5 times the radial thickness of the cross sections of the first coil 11 and the third coil 13.
[0038] In the embodiment of the present application, the ratio a / b of the axial width and radial thickness of the cross section of the second coil 12 is preferably 6, the ratio a / b of the axial width and radial thickness of the cross section of the first coil 11 and the third coil 13 is preferably 1.6, the axial width of the cross section of the second coil 12 is twice the axial width of the cross section of the first coil 11 and the third coil 13, and the radial thickness of the cross section of the second coil 12 is 0.5 times the radial thickness of the cross section of the first coil 11 and the third coil 13. In other embodiments, the ratio a / b of the axial width and radial thickness of the cross section of the second coil 12 can also be 8, the ratio a / b of the axial width and radial thickness of the cross section of the first coil 11 and the third coil 13 can also be 1.4, the axial width of the cross section of the second coil 12 is 2.3 times the axial width of the cross section of the first coil 11 and the third coil 13, and the radial thickness of the cross section of the second coil 12 is 0.4 times the radial thickness of the cross section of the first coil 11 and the third coil 13.
[0039] Reference Figure 2 , an inclined portion 111 is provided on the side of the first coil 11 facing away from the second coil 12, and an inclined portion 111 is also provided on the side of the third coil 13 facing away from the second coil 12, and the inclined surface of the inclined portion 111 is provided with a stepped surface, and the inclined portion 111 is filled with an insulating material 112. The edges of the insulating material are smooth, without burrs, and without damage, delamination, or cracks. In an embodiment of the present application, the insulating material 112 is preferably insulating paper, and the insulating paper is made of sulfate fiber paper. In other embodiments, the insulating material 112 can also be insulating cardboard or other insulating molding materials, and the insulating cardboard is T4 cardboard, which is densified to enhance mechanical strength.
[0040] The implementation principle of a transformer in Example 1 of the present application is as follows: the axial width of the cross-section of the second coil 12 is larger, and the radial thickness is smaller, so the coil eddy current loss generated by the axial component of the leakage magnetic field is smaller, thereby making the eddy current loss generated by the leakage magnetic field in the second coil 12 smaller; compared with the second coil 12, the axial width of the cross-section of the first coil 11 and the third coil 13 is reduced, and the radial thickness is increased, so the coil eddy current loss generated by the radial component of the leakage magnetic field is smaller, thereby making the eddy current loss generated by the leakage magnetic field in the first coil 11 and the third coil 13 less.
[0041] Embodiment 2:
[0042] The difference from the first embodiment is that the structures of the first coil 11 and the third coil 13 are different.
[0043] Reference Figure 3The first coil 11 and the third coil 13 include a plurality of sub-coils 113, and the plurality of sub-coils 113 are arranged in an axial spiral. The ratios of the axial width to the radial thickness of the cross-sections of the sub-coils 113 are different. The ratio of the axial width to the radial thickness of the sub-coil 113 arranged on the side close to the second coil 12 is greater than the ratio of the axial width to the radial thickness of the sub-coil 113 arranged on the side away from the second coil 12.
[0044] In the application embodiment, the ratio a / b of the axial width and radial thickness of the cross section of the sub-coil 113 arranged on the side away from the second coil 12 is 1.4, the ratio a / b of the axial width and radial thickness of the cross section of the sub-coil 113 arranged on the side close to the second coil 12 is 1.8, and the ratio a / b of the axial width and radial thickness of the cross section of the sub-coil 113 arranged in the middle part of the first coil 11 is 1.6. In other embodiments, the ratio a / b of the axial width and radial thickness of the cross section of the sub-coil 113 arranged on the side away from the second coil 12 can also be 1.5, the ratio a / b of the axial width and radial thickness of the cross section of the sub-coil 113 arranged on the side close to the second coil 12 can also be 1.7, and the ratio of the axial width and radial thickness of the cross section of the sub-coil 113 arranged in the middle part of the first coil 11 can also be 1.55.
[0045] The implementation principle of a transformer in Example 2 of the present application is as follows: the axial width of the cross-section of the first coil 11 and the third coil 13 gradually decreases, and the radial thickness gradually increases, so that the coil eddy current loss generated by the radial component of the leakage magnetic field is small, thereby reducing the eddy current loss generated by the leakage magnetic field in the first coil 11 and the third coil 13.
[0046] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.
Claims
1. A transformer coil with low eddy current loss, characterized in that: The invention comprises a low-voltage coil (1) and a high-voltage coil (2) arranged outside the low-voltage coil (1), wherein the upper ends of the low-voltage coil (1) and the high-voltage coil (2) are arranged as a first coil (11), the middle sections are arranged as a second coil (12), and the lower ends are arranged as a third coil (13), the ratio of the axial width to the radial thickness of the cross section of the second coil (12) is in the range of 5-8, the ratio of the axial width to the radial thickness of the first coil (11) and the third coil (13) is in the range of 1.4-1.8, and the ends of the first coil (11) and the third coil (13) are arranged with inclined portions (111).
2. The transformer coil with low eddy current loss according to claim 1, characterized in that: The inclined surface of the inclined portion (111) is configured as a stepped surface.
3. The transformer coil with low eddy current loss according to claim 1, characterized in that: An insulating material (112) is disposed in the inclined portion (111).
4. The transformer coil with low eddy current loss according to claim 1, characterized in that: The axial width of the cross section of the second coil (12) is 2-2.5 times the axial width of the cross sections of the first coil (11) and the third coil (13), and the radial thickness of the cross section of the second coil (12) is 0.3-0.5 times the radial thickness of the cross sections of the first coil (11) and the third coil (13).
5. The transformer coil with low eddy current loss according to claim 1, characterized in that: The first coil (11) and the third coil (13) include a plurality of sub-coils (113) arranged along the axial direction, and the ratio of the axial width to the radial thickness of the cross section of the sub-coil (113) gradually decreases in a direction away from the second coil (12).
6. The transformer coil with low eddy current loss according to claim 1, characterized in that: An insulating cylinder (3) is connected to a side of the low-voltage coil (1) close to the high-voltage coil (2).
7. The transformer coil with low eddy current loss according to claim 6, characterized in that: A heat dissipation cavity (4) is provided between the insulating cylinder (3) and the high-voltage coil (2).
8. The transformer coil with low eddy current loss according to claim 6, characterized in that: A limiting block (5) is connected between the insulating cylinder (3) and the high-voltage coil (2).
9. A transformer, characterized in that: A transformer coil with low eddy current loss comprising the coil described in any one of claims 1 to 8.