Transformer and switching power supply
By winding a metal shielding layer around the transformer body and connecting it to the grounding terminal, an equivalent Y capacitor is formed, which solves the problem of poor EMI characteristics and improves the electromagnetic interference suppression capability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- DONGGUAN AOHAI TECH CO LTD
- Filing Date
- 2025-04-17
- Publication Date
- 2026-04-14
AI Technical Summary
When addressing EMI issues, traditional power supplies have limitations in increasing the capacitance of the Y capacitor, which prevents them from increasing the margin and affects the EMI characteristics of small-sized, high-power-density power supply products.
First and second metal shielding layers are wound around the transformer body and connected to the primary and secondary grounding terminals to form an equivalent Y capacitor, increasing the capacitance and improving EMI characteristics.
Without increasing the volume, it improves the margin for conducted and radiated tests and enhances the ability to suppress electromagnetic interference.
Smart Images
Figure CN224123231U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of transformer technology, and in particular to a transformer and a switching power supply. Background Technology
[0002] When traditional power supplies address EMI (Electromagnetic Interference) issues, they often increase the capacitance of the Y capacitor to increase the margin in EMI testing. However, when upstream customers impose stringent restrictions on the capacitance of the Y capacitor, it becomes impossible to increase the margin by increasing its capacitance. For small-sized, high-power-density power supply products, this can severely impact the EMI characteristics of the power supply. Utility Model Content
[0003] This utility model provides a transformer and a switching power supply to solve the problem of poor MEI characteristics of existing transformers.
[0004] A transformer includes a transformer body, a first metal shielding layer, and a second metal shielding layer;
[0005] The first metal shielding layer is wound around the transformer body along a first direction and connected to the primary grounding terminal of the transformer body;
[0006] The second metal shielding layer is wound around the first metal shielding layer along the first direction and connected to the secondary grounding terminal of the transformer body.
[0007] Furthermore, the second metal shielding layer is not joined end to end.
[0008] Furthermore, the first metal shielding layer is welded to the primary grounding terminal via a first conductor; the second metal shielding layer is welded to the secondary grounding terminal via a second conductor.
[0009] Furthermore, the transformer also includes a third metallic shielding layer;
[0010] The third metal shielding layer is wound around the transformer body along the second direction and is located between the transformer body and the first metal shielding layer;
[0011] The third metal shielding layer is welded to the first metal shielding layer.
[0012] Furthermore, the first direction and the second direction are perpendicular to each other.
[0013] Furthermore, the first metal shielding layer and the second metal shielding layer are elongated strips; the width of the second metal shielding layer is greater than the width of the first metal shielding layer.
[0014] Furthermore, the transformer body includes a frame, a magnetic core, and coil windings;
[0015] The skeleton is fitted onto the magnetic core;
[0016] The coil winding is wound around the frame;
[0017] The primary coil grounding terminal of the coil winding is connected to the primary grounding terminal on the frame; the secondary coil grounding terminal of the coil winding is connected to the secondary grounding terminal on the frame.
[0018] Furthermore, the first direction is the direction of the coil winding.
[0019] Furthermore, the first metal shielding layer and / or the second metal shielding layer are copper foil.
[0020] A switching power supply, comprising the aforementioned transformer.
[0021] This utility model provides a transformer and a switching power supply. The transformer includes a transformer body, a first metal shielding layer, and a second metal shielding layer. By winding the first metal shielding layer along a first direction onto the transformer body and connecting it to the primary grounding terminal of the transformer body, and winding the second metal shielding layer along the first direction onto the first metal shielding layer and connecting it to the secondary grounding terminal of the transformer body, the first and second metal shielding layers are equivalent to a Y-capacitor formed between the primary and secondary coils of the transformer body without increasing the volume. This effectively increases the capacitance value of the Y-capacitor, thereby improving the test margin for conduction and radiation. Attached Figure Description
[0022] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model 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 these drawings without creative effort.
[0023] Figure 1 This is a schematic diagram of a transformer according to one embodiment of the present invention;
[0024] Figure 2 This is an exploded view of a transformer according to one embodiment of the present invention;
[0025] Figure 3 This is an equivalent circuit diagram of a transformer in one embodiment of the present invention.
[0026] In the diagram: 1. Transformer body; 11. Frame; 12. Magnetic core; 13. Coil winding; 2. First metal shielding layer; 3. Second metal shielding layer; 4. Third metal shielding layer; 5. Primary grounding terminal; 6. Secondary grounding terminal. Detailed Implementation
[0027] 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, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present utility model.
[0028] It should be understood that this invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this invention to those skilled in the art. In the drawings, for clarity, the dimensions of layers and regions, as well as their relative dimensions, may be exaggerated. The same reference numerals denote the same elements throughout.
[0029] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this utility model, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.
[0030] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below,” “under,” or “below” other elements or features will be oriented “above” other elements or features. Therefore, the exemplary terms “below” and “under” can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.
[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. When used herein, the singular forms “a,” “an,” and “ / the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “comprising,” when used in this specification, identify the presence of features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.
[0032] To fully understand this utility model, detailed structures and steps will be presented in the following description to illustrate the technical solution proposed by this utility model. Preferred embodiments of this utility model are described in detail below; however, in addition to these detailed descriptions, this utility model may have other embodiments.
[0033] This embodiment provides a transformer, such as Figures 1 to 3 As shown, it includes a transformer body 1, a first metal shielding layer 2, and a second metal shielding layer 3; the first metal shielding layer 2 is wound around the transformer body 1 along a first direction and is connected to the primary grounding terminal 5 of the transformer body 1; the second metal shielding layer 3 is wound around the first metal shielding layer 2 along the first direction and is connected to the secondary grounding terminal 6 of the transformer body 1.
[0034] In this embodiment, by winding the first metal shielding layer 2 along the first direction onto the transformer body 1 and connecting it to the primary grounding terminal 5 of the transformer body 1, and winding the second metal shielding layer 3 along the first direction onto the first metal shielding layer 2 and connecting it to the secondary grounding terminal 6 of the transformer body 1, the first metal shielding layer 2 and the second metal shielding layer 3 are equivalent to a Y capacitor formed between the primary coil and the secondary coil of the transformer body 1 without increasing the volume. This effectively increases the capacitance value of the Y capacitor, thereby improving the test margin for conduction and radiation.
[0035] In one embodiment, the second metal shielding layer 3 is not connected end-to-end. In this embodiment, ensuring that the second metal shielding layer 3 is not connected end-to-end improves the filtering effect on high-frequency noise and avoids eddy current losses caused by forming a closed loop.
[0036] In one embodiment, the first metal shielding layer 2 is welded to the primary grounding terminal 5 via a first conductor; the second metal shielding layer 3 is welded to the secondary grounding terminal 6 via a second conductor.
[0037] In this embodiment, the first metal shielding layer 2 is welded to the primary grounding terminal 5 via a first wire; the second metal shielding layer 3 is welded to the secondary grounding terminal 6 via a second wire, thereby making the first metal shielding layer 2 and the second metal shielding layer 3 equivalent to a Y capacitor formed between the primary coil and the secondary coil of the transformer body 1.
[0038] In one embodiment, the transformer further includes a third metal shielding layer 4; the third metal shielding layer 4 is wound around the transformer body 1 along a second direction and is located between the transformer body 1 and the first metal shielding layer 2; the third metal shielding layer 4 is welded to the first metal shielding layer 2.
[0039] In this embodiment, the third metal shielding layer 4 is wound around the transformer body 1 along the second direction and is located between the transformer body 1 and the first metal shielding layer 2; the third metal shielding layer 4 is welded to the first metal shielding layer 2 to further improve the electromagnetic interference suppression capability.
[0040] For example, the first and last welding points of the first metal shielding layer 2 and the first and last welding points of the third metal shielding layer 4 are on the same side. The first and last welding points of the first metal shielding layer 2 and the first and last welding points of the third metal shielding layer 4 are the same welding point, which facilitates welding and reduces welding costs.
[0041] In one embodiment, the first direction and the second direction are perpendicular to each other. Exemplarily, the first direction is the direction of the coil winding 13 of the transformer body 1, and the second direction is the direction of the magnetic core 12 of the transformer body 1. In this example, a third metal shielding layer 4 is wound around the transformer body 1 along the second direction, located between the transformer body 1 and the first metal shielding layer 2; the third metal shielding layer 4 is welded to the first metal shielding layer 2, and the first direction and the second direction are perpendicular to each other, thereby increasing the coverage area of the transformer body 1 through the first metal shielding layer 2 and the third metal shielding layer 4, further improving the electromagnetic interference suppression capability.
[0042] In one embodiment, the first metal shielding layer 2 and the second metal shielding layer 3 are elongated strips; the width of the second metal shielding layer 3 is greater than the width of the first metal shielding layer 2. In this embodiment, the width of the second metal shielding layer 3 is greater than the width of the first metal shielding layer 2 to increase the capacitance of the formed Y capacitor and improve the test margin for conduction and radiation.
[0043] In one embodiment, the transformer body 1 includes a frame 11, a magnetic core 12, and a coil winding 13; the frame 11 is sleeved on the magnetic core 12; the coil winding 13 is wound on the frame 11; the primary coil grounding terminal of the coil winding 13 is connected to the primary grounding terminal 5 on the frame 11; and the secondary coil grounding terminal of the coil winding 13 is connected to the secondary grounding terminal 6 on the frame 11.
[0044] As an example, the frame 11 is provided with a primary ground terminal 5 and a secondary ground terminal 6. The coil winding 13 includes a primary coil and a secondary coil. The primary coil and the secondary coil are wound on the frame 11, the primary coil ground terminal is connected to the primary ground terminal 5 on the frame 11, and the secondary coil ground terminal is connected to the secondary ground terminal 6 on the frame 11.
[0045] As an example, the first direction is the direction of the coil winding 13, and the second direction is the direction of the magnetic core 12.
[0046] In this embodiment, the primary coil grounding terminal of the coil winding 13 is connected to the first metal shielding layer 2 through the primary grounding terminal 5 on the frame 11, and the secondary coil grounding terminal of the coil winding 13 is connected to the second metal shielding layer 3 through the secondary grounding terminal 6 on the frame 11. This makes the first metal shielding layer 2 and the second metal shielding layer 3 equivalent to the Y capacitor formed between the primary coil and the secondary coil of the transformer body 1, which effectively increases the capacitance value of the Y capacitor, thereby increasing the test margin of the transformer's conduction and radiation.
[0047] In one embodiment, the first metal shielding layer 2 and / or the second metal shielding layer 3 are copper foils. In this embodiment, the first metal shielding layer 2 and / or the second metal shielding layer 3 are copper foils, thereby reducing costs while ensuring electrical performance.
[0048] This embodiment provides a switching power supply, including the transformer described above.
[0049] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be included within the protection scope of this utility model.
Claims
1. A transformer, characterized by It includes the transformer body, the first metal shielding layer, and the second metal shielding layer; The first metal shielding layer is wound around the transformer body along a first direction and connected to the primary grounding terminal of the transformer body; The second metal shielding layer is wound around the first metal shielding layer along the first direction and connected to the secondary grounding terminal of the transformer body.
2. The transformer of claim 1, wherein, The second metal shielding layer is not connected end to end.
3. The transformer of claim 1, wherein, The first metal shielding layer is welded to the primary grounding terminal via a first conductor; the second metal shielding layer is welded to the secondary grounding terminal via a second conductor.
4. The transformer of claim 1, wherein, The transformer also includes a third metal shielding layer; The third metal shielding layer is wound around the transformer body along the second direction and is located between the transformer body and the first metal shielding layer; The third metal shielding layer is welded to the first metal shielding layer.
5. The transformer of claim 4, wherein, The first direction and the second direction are perpendicular to each other.
6. The transformer of claim 1, wherein, The first metal shielding layer and the second metal shielding layer are elongated strips; the width of the second metal shielding layer is greater than the width of the first metal shielding layer.
7. The transformer of claim 1, wherein The transformer body includes a frame, a magnetic core, and coil windings; The skeleton is fitted onto the magnetic core; The coil winding is wound around the frame; The primary coil grounding terminal of the coil winding is connected to the primary grounding terminal on the frame; the secondary coil grounding terminal of the coil winding is connected to the secondary grounding terminal on the frame.
8. The transformer of claim 7, wherein, The first direction is the direction of the coil winding.
9. The transformer of claim 1, wherein, The first metal shielding layer and / or the second metal shielding layer are copper foil.
10. A switching power supply, characterized by comprising: Including the transformer as described in any one of claims 1 to 9.