Resonance transformer structure with adjustable leakage inductance
By setting a thin magnetic ring on the support frame of the high-frequency transformer to change the coupling degree of the primary stage, the problem of difficulty in adjusting the leakage inductance in the prior art is solved, and flexible adjustment and efficiency improvement of the leakage inductance are achieved.
Patent Information
- Application Number
- CN202421220898.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-30
- Publication Date
- 2025-03-11
- Estimated Expiration
- 2034-05-30
AI Technical Summary
In the LLC resonant network in bridge topology circuits, it is difficult to effectively adjust the leakage inductance to meet various resonant frequency requirements, resulting in an increase in the transformer volume, an increase in leakage magnetic leakage and low efficiency.
A leakage inductance tunable resonant transformer structure is designed to adjust the native leakage inductance by setting a thin magnetic ring on the support frame to change the coupling degree of the primary stage. The structure includes a main core group, a support frame, a thin magnetic ring, a primary winding and a secondary winding. The thin magnetic ring is located between the primary and secondary windings, and the central pillar passes through the central circular hole of the thin magnetic ring to change the coupling degree of the primary secondary.
It realizes flexible adjustment of leakage inductance, meets various resonant frequency requirements, simplifies the transformer production process, and reduces production costs.
Smart Images
Figure CN222600704U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of high-frequency transformers, in particular to a leakage inductance adjustable resonant transformer structure. Background Art
[0002] In high-frequency switching power supply circuits, especially in bridge topology circuits, the LLC resonant network includes the transformer's magnetizing inductance Lm, leakage inductance Lk and resonant capacitor Cr. Common design methods:
[0003] First, a traditional transformer plus an independent resonant inductor is used, which takes up a large PCB space and has a high power cost.
[0004] Second, the primary coil and the secondary coil are wound separately on a double-slot frame, and the leakage inductance is adjusted by adjusting the number of coil turns and the distance between the primary and secondary winding slots. This will cause the transformer to be larger in size, have greater leakage flux, and have lower efficiency. Moreover, under certain conditions, the range in which the leakage inductance can be increased is very limited.
[0005] The third method is to add a magnetic shunt between the primary and secondary coils to increase the leakage inductance between the primary and secondary coils. However, the existing method has a complex structure and high material and production costs. Utility Model Content
[0006] The purpose of the utility model includes, for example, providing a leakage inductance adjustable resonant transformer structure, which can change the primary and secondary coupling degree through a thin magnetic conductive ring when the transformer is working, thereby changing the native leakage inductance to meet various resonant frequency requirements.
[0007] The embodiments of the present invention can be implemented as follows:
[0008] In a first aspect, the utility model provides a leakage inductance adjustable resonant transformer structure, comprising:
[0009] Main magnetic core group, supporting frame, thin magnetic ring, primary winding, secondary winding;
[0010] The support frame is arranged in the main magnetic core group; the primary winding is arranged at the top of the support frame, and the secondary winding is arranged at the bottom of the support frame;
[0011] The thin magnetic conductive ring is arranged on the supporting frame; and is in a square shape along the height of the supporting frame, and the thin magnetic conductive ring is located between the primary winding and the secondary winding;
[0012] The main magnetic core group has a middle column, the primary winding has a first through hole, the secondary winding has a second through hole, and the thin magnetic conductive ring has a central circular hole; the middle column is sequentially perforated with the first through hole, the central circular hole, and the second through hole;
[0013] The thin magnetic conductive ring is configured to change the coupling degree between the primary and secondary, thereby changing the native leakage inductance to meet various resonant frequency requirements.
[0014] In an optional embodiment, the main magnetic core group includes two symmetrically arranged magnetic cores; the magnetic core includes a base plate, a core column and side legs symmetrically arranged on both sides of the core column; the core column and the side legs are arranged on the same side of the base plate, and the edges of the side legs are flush with the edges of the base plate; along the length direction of the side legs, the thickness of the side legs gradually increases.
[0015] In an optional embodiment, along the cross-sectional direction of the magnetic core, the sum of the cross-sectional areas of the two side legs is greater than or equal to the cross-sectional area of the core column.
[0016] In an optional embodiment, the thin magnetic conductive ring includes a semicircular plate and a square plate, the diameter side of the semicircular plate is connected to the long side of the square plate; the length of the long side is smaller than the diameter of the semicircular plate.
[0017] In an optional embodiment, the support frame has a receiving portion; the receiving portion includes two baffles arranged in parallel and a connecting block connected to the two baffles;
[0018] The square plate can be inserted into the accommodation space formed by the two baffles, and the semicircular plate can correspond to the edge of the baffle;
[0019] The baffles are each provided with a matching circular hole corresponding to the central circular hole; the diameter of the matching circular hole is smaller than the diameter of the semicircular plate and larger than the diameter of the central column;
[0020] The center column can be sequentially perforated with the first through hole, the matching circular hole, the central circular hole, and the second through hole.
[0021] In an optional embodiment, in the leakage inductance tunable resonant transformer structure, the baffle includes a semicircular arc portion and a rectangular square portion; the diameter of the arc portion is equal to the length of the long side of the square portion, and the straight side of the arc portion is connected to the long side of the square portion; the diameter of the arc portion is greater than or equal to the diameter of the semicircular plate of the thin magnetic conductive ring;
[0022] The accommodating portion further comprises two side plates; the two side plates are located at the two ends of the long side of the square portion, and the upper and lower sides of the side plates are respectively connected to the two baffles; one end of the side plate in the width direction is connected to the connecting block, and the other end extends to the straight side of the arc portion; the two side plates, the two baffles and the connecting block enclose a accommodating groove facing the arc portion, and the accommodating groove is used to accommodate the thin magnetic conductive ring;
[0023] The length of the side plate is greater than the radius of the arc portion by more than 6 mm.
[0024] In an optional embodiment, a wiring groove is provided on the side of the connection block;
[0025] The primary lead wire of the primary coil of the primary winding passes through the wiring groove and is connected to the lead pin at the bottom of the supporting frame.
[0026] In an optional embodiment, a protective cover is further included; the protective cover is arranged in the main magnetic core group, and after the protective cover wraps the primary winding, it extends in a direction away from the main magnetic core group to increase the safety creepage distance.
[0027] In an optional embodiment, the protective cover comprises a U-shaped annular plate, and flanges respectively arranged at the top and bottom of the annular plate; the flanges maintain an angle with the plate surface of the annular plate;
[0028] A primary seat body for mounting the primary winding is provided on the top of the support frame, and the two flanges can be embedded in the primary seat body to ensure that the primary winding and the secondary winding have a safe distance.
[0029] In an optional embodiment, the flange remains perpendicular to the plate surface of the annular plate.
[0030] The beneficial effects of the embodiments of the present utility model include, for example:
[0031] Such a leakage inductance adjustable resonant transformer structure includes a main magnetic core group, a support frame, a thin magnetic conductive ring, a primary winding, and a secondary winding. The thin magnetic conductive ring is arranged on the support frame; and the thin magnetic conductive ring is located between the primary winding and the secondary winding; the middle column of the main magnetic core group is sequentially penetrated by the first through hole of the primary winding, the central circular hole of the thin magnetic conductive ring, and the second through hole of the secondary winding. The thin magnetic conductive ring is configured to change the coupling degree between the primary and secondary, thereby changing the native leakage inductance to meet various resonant frequency requirements. Furthermore, the leakage inductance size is adjusted by selecting thin magnetic conductive rings with different inner diameter sizes, and the structure is simple, which greatly simplifies the transformer production process. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.
[0033] Figure 1 A schematic diagram of the structure of a leakage inductance adjustable resonant transformer according to an embodiment of the utility model;
[0034] Figure 2 A schematic structural diagram of the leakage inductance adjustable resonant transformer structure from another perspective of an embodiment of the utility model;
[0035] Figure 3 It is a schematic diagram of the assembly of the leakage inductance adjustable resonant transformer structure of the embodiment of the utility model;
[0036] Figure 4 A schematic structural diagram of a main magnetic core group of a leakage inductance adjustable resonant transformer structure according to an embodiment of the utility model;
[0037] Figure 5 A schematic diagram of the structure of a thin magnetic conductive ring of a leakage inductance adjustable resonant transformer structure according to an embodiment of the utility model;
[0038] Figure 6 A schematic diagram of the structure of the support frame of the leakage inductance adjustable resonant transformer structure according to an embodiment of the utility model;
[0039] Figure 7 A structural schematic diagram of a support frame of a leakage inductance adjustable resonant transformer structure according to an embodiment of the utility model from another perspective;
[0040] Figure 8 It is a schematic structural diagram of the protective cover of the leakage inductance adjustable resonant transformer structure according to an embodiment of the utility model.
[0041] Icons: 100-main magnetic core group; 110-bottom plate; 120-core column; 130-side leg; 200-support frame; 201-accommodating part; 210-baffle; 211-arc part; 212-square part; 220-connecting block; 222-wiring groove; 230-side plate; 300-thin magnetic conductive ring; 301-center circular hole; 310-semicircular plate; 320-square plate; 410-primary winding; 411-first perforation; 420-secondary winding; 422-second perforation; 500-middle column; 600-protective cover; 610-ring plate; 620-flanged edge. DETAILED DESCRIPTION
[0042] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.
[0043] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0044] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.
[0045] In the description of the present utility model, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the utility model product is usually placed when used. It is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present utility model.
[0046] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.
[0047] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.
[0048] Please refer to Figure 1 , Figure 2 and Figure 3 , this embodiment provides a leakage inductance tunable resonant transformer structure, including:
[0049] Main magnetic core assembly 100, support frame 200, thin magnetic conductive ring 300, primary winding 410, secondary winding 420;
[0050] The support frame 200 is disposed in the main magnetic core group 100; the primary winding 410 is disposed on the top of the support frame 200, and the secondary winding 420 is disposed on the bottom of the support frame 200;
[0051] The thin magnetic conductive ring 300 is disposed on the support frame 200 and is in a square shape along the height of the support frame 200. The thin magnetic conductive ring 300 is located between the primary winding 410 and the secondary winding 420.
[0052] The main magnetic core assembly 100 has a center column 500, the primary winding 410 has a first through hole 411, the secondary winding 420 has a second through hole 422, and the thin magnetic conductive ring 300 has a central circular hole 301; the center column 500 is sequentially penetrated with the first through hole 411, the central circular hole 301, and the second through hole 422;
[0053] The thin magnetic conductive ring 300 is configured to change the coupling degree between the primary and secondary, thereby changing the native leakage inductance to meet various resonant frequency requirements.
[0054] Because the thin magnetic conductive ring 300 is located between the primary winding 410 and the secondary winding 420; the middle column 500 of the main magnetic core group 100 is sequentially penetrated by the first through hole 411 of the primary winding 410, the central circular hole 301 of the thin magnetic conductive ring 300, and the second through hole 422 of the secondary winding 420. The thin magnetic conductive ring 300 is configured to change the coupling degree between the primary and secondary, thereby changing the native leakage inductance to meet various resonant frequency requirements. Furthermore, the leakage inductance size is adjusted by selecting thin magnetic conductive rings 300 with different inner diameter sizes, and the structure is simple, which greatly simplifies the transformer production process. When the main magnetic core and coil (wire diameter, number of turns) remain unchanged, the leakage inductance size can be changed by only replacing the thin magnetic conductive ring 300 with different inner and outer diameters. That is, multiple models of products can be produced with unified coils and main magnetic cores, which is conducive to automated production and reduces production costs.
[0055] Please read further Figures 1 to 8 , for more details on the leakage inductance tunable resonant transformer structure.
[0056] The primary winding 410 includes a primary coil, and the secondary winding 420 includes a secondary coil. It can also be seen from the figure that the support frame 200 is a vertical structure. The top of the support frame 200 is provided with a primary coil winding area, the middle of the frame is a thin magnetic ring 300 accommodating portion 201, and the bottom of the frame is provided with a secondary coil winding area and a lead pin base. The lead pin base is provided with a lead pin, and the lead wires of the primary coil and the lead wires of the secondary coil are both connected to the lead pin.
[0057] like Figure 3 and Figure 4 As shown, in this embodiment of the utility model, the main magnetic core group 100 includes two symmetrically arranged magnetic cores; the magnetic core includes a bottom plate 110, a core column 120 and side legs 130 symmetrically arranged on both sides of the core column 120; the core column 120 and the side legs 130 are both arranged on the same side of the bottom plate 110, and the edge of the side leg 130 is flush with the edge of the bottom plate 110; along the length direction of the side leg 130, the thickness of the side leg 130 gradually increases. Further, the magnetic core is a cylinder (that is, the middle column 500 of the main magnetic core group 100 is a cylinder), the two side legs 130 are cylinders with a cross section similar to a "P" shape, and the bottom plate 110 is a rectangular parallelepiped.
[0058] Optionally, along the cross-sectional direction of the magnetic core, the sum of the cross-sectional areas of the two side legs 130 is greater than or equal to the cross-sectional area of the core column 120. In this way, the main magnetic core assembly 100 has better stability and reliability.
[0059] like Figure 5 As shown, in this embodiment of the utility model, the thin magnetic conductive ring 300 includes a semicircular plate 310 and a square plate 320 , the diameter side of the semicircular plate 310 is connected to the long side of the square plate 320 ; the length of the long side is smaller than the diameter of the semicircular plate 310 .
[0060] See also Figure 1 , Figure 2 , Figure 3 , Figure 5 , Figure 6 and Figure 7 In this embodiment of the utility model, the support frame 200 has a receiving portion 201; the receiving portion 201 includes two baffles 210 arranged in parallel and a connecting block 220 connected to the two baffles 210; the square plate 320 can be inserted into the receiving space formed by the two baffles 210, and the semicircular plate 310 can correspond to the edge of the baffle 210; the baffles 210 are provided with matching circular holes corresponding to the central circular hole 301; the diameter of the matching circular hole is smaller than the diameter of the semicircular plate 310 and larger than the diameter of the middle column 500; the middle column 500 can be sequentially penetrated with a first through hole 411, a matching circular hole, a central circular hole 301, and a second through hole 422. This receiving portion 201 can ensure the storage of the thin magnetic conductive ring 300, and can also play a role in supporting the middle column 500.
[0061] Further, in the present embodiment of the utility model, the leakage inductance adjustable resonant transformer structure, the baffle 210 includes a semicircular arc portion 211 and a rectangular square portion 212; the diameter of the arc portion 211 is equal to the length of the long side of the square portion 212, and the straight side of the arc portion 211 is connected to the long side of the square portion 212; the diameter of the arc portion 211 is greater than or equal to the diameter of the semicircular plate 310 of the thin magnetic conductive ring 300;
[0062] The accommodating portion 201 also includes two side panels 230; the two side panels 230 are located at the two ends of the long side of the square portion 212, and the upper and lower sides of the side panels 230 are respectively connected to the two baffles 210; one end of the side panel 230 in the width direction is connected to the connecting block 220, and the other end extends to the straight side of the arc portion 211; the two side panels 230, the two baffles 210 and the connecting block 220 are combined to form an accommodating groove facing the arc portion 211, and the accommodating groove is used to accommodate the thin magnetic conductive ring 300; the length of the side panel 230 is greater than the radius of the arc portion 211 by more than 6 mm.
[0063] Half of the square plate 320 of the thin magnetic ring 300 is inserted into the receiving groove, so that the middle circular hole of the thin magnetic ring 300 and the middle circular holes of the two winding areas of the support frame 200 (the first through hole 411 and the second through hole 422) form a through hole for the main magnetic core center column 500 to be inserted.
[0064] Further, in this embodiment of the utility model, a wiring groove 222 is provided on the side of the connection block 220; the primary lead of the primary coil of the primary winding 410 passes through the wiring groove 222 and is connected to the lead pin at the bottom of the support frame 200. Specifically, the primary lead passes through the wiring groove 222 and is connected to the lead pin at the bottom of the support frame 200.
[0065] It can also be seen from the figure that Figure 1 , Figure 2 , Figure 3 and Figure 8 As shown, in this embodiment of the utility model, the leakage inductance tunable resonant transformer structure also includes a protective cover 600; the protective cover 600 is arranged in the main magnetic core group 100, and the protective cover 600 wraps the primary winding 410 and then extends in a direction away from the main magnetic core group 100 to increase the safety creepage distance.
[0066] In this embodiment of the utility model, the protective cover 600 includes a U-shaped annular plate 610, and flanges 620 respectively arranged at the top and bottom of the annular plate 610; the flanges 620 maintain an angle with the plate surface of the annular plate 610; the top of the support frame 200 is provided with a primary seat body for mounting the primary winding 410, and the two flanges 620 can be embedded in the primary seat body to ensure that the primary winding 410 has a safe distance from the secondary winding 420. Optionally, the flanges 620 are perpendicular to the plate surface of the annular plate 610.
[0067] Furthermore, it can be seen from the figure that the opening direction of the U-shaped protective cover 600 is opposite to the opening direction of the magnetic shunt core accommodating area, so as to increase the creepage distance and electrical clearance.
[0068] In summary, the embodiment of the utility model provides a leakage inductance tunable resonant transformer structure, which has at least the following advantages:
[0069] The thin magnetic ring 300 in the middle of the primary and secondary windings 420 changes the coupling degree between the primary and secondary windings when the transformer is working, thereby changing the original leakage inductance to meet various resonant frequency requirements. The structural design is simple and clear, which can greatly simplify the transformer production process, and thin magnetic rings 300 with different inner diameters can be selected to adjust the leakage inductance.
[0070] The above are only specific implementations of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.
Claims
1. A leakage inductance adjustable resonant transformer structure, characterized in that: include: A main magnetic core group (100), a supporting frame (200), a thin magnetic conductive ring (300), a primary winding (410), and a secondary winding (420); The support frame (200) is arranged in the main magnetic core group (100); the primary winding (410) is arranged at the top of the support frame (200), and the secondary winding (420) is arranged at the bottom of the support frame (200); The thin magnetic conductive ring (300) is arranged on the supporting frame (200); and is in a square shape along the height of the supporting frame (200), and the thin magnetic conductive ring (300) is located between the primary winding (410) and the secondary winding (420); The main magnetic core group (100) has a middle column (500), the primary winding (410) has a first through hole (411), the secondary winding (420) has a second through hole (422), and the thin magnetic conductive ring (300) has a central circular hole (301); the middle column (500) is sequentially perforated with the first through hole (411), the central circular hole (301), and the second through hole (422); The thin magnetic conductive ring (300) is configured to change the coupling degree between the primary and secondary, thereby changing the native leakage inductance to meet various resonant frequency requirements.
2. The leakage inductance tunable resonant transformer structure according to claim 1, characterized in that: The main magnetic core group (100) comprises two symmetrically arranged magnetic cores; the magnetic core comprises a bottom plate (110), a core column (120) and side legs (130) symmetrically arranged on both sides of the core column (120); the core column (120) and the side legs (130) are both arranged on the same side of the bottom plate (110), and the edge of the side leg (130) is flush with the edge of the bottom plate (110); along the length direction of the side leg (130), the thickness of the side leg (130) gradually increases.
3. The leakage inductance tunable resonant transformer structure according to claim 2, characterized in that: Along the cross-sectional direction of the magnetic core, the sum of the cross-sectional areas of the two side legs (130) is greater than or equal to the cross-sectional area of the core column (120).
4. The leakage inductance tunable resonant transformer structure according to claim 1, characterized in that: The thin magnetic conductive ring (300) comprises a semicircular plate (310) and a square plate (320); the diameter side of the semicircular plate (310) is connected to the long side of the square plate (320); and the length of the long side is smaller than the diameter of the semicircular plate (310).
5. The leakage inductance tunable resonant transformer structure according to claim 4, characterized in that: The support frame (200) has a receiving portion (201); the receiving portion (201) comprises two baffles (210) arranged in parallel and a connecting block (220) connected to the two baffles (210); The square plate (320) can be inserted into the accommodation space enclosed by the two baffles (210), and the semicircular plate (310) can correspond to the edge of the baffle (210); The baffle plates (210) are each provided with a matching circular hole corresponding to the central circular hole (301); the diameter of the matching circular hole is smaller than the diameter of the semicircular plate (310) and larger than the diameter of the central column (500); The center column (500) can be sequentially perforated with the first through hole (411), the matching circular hole, the central circular hole (301), and the second through hole (422).
6. The leakage inductance tunable resonant transformer structure according to claim 5, characterized in that: The leakage inductance adjustable resonant transformer structure is characterized by: The baffle (210) comprises a semicircular arc portion (211) and a rectangular square portion (212); the diameter of the arc portion (211) is equal to the length of the long side of the square portion (212), and the straight side of the arc portion (211) is connected to the long side of the square portion (212); the diameter of the arc portion (211) is greater than or equal to the diameter of the semicircular plate (310) of the thin magnetic conductive ring (300); The accommodating portion (201) further comprises two side plates (230); the two side plates (230) are located at the two ends of the long side of the square portion (212), and the upper and lower sides of the side plates (230) are respectively connected to the two baffles (210); one end of the side plate (230) in the width direction is connected to the connecting block (220), and the other end extends to the straight side of the arc portion (211); the two side plates (230), the two baffles (210) and the connecting block (220) are enclosed to form an accommodating groove facing the arc portion (211), and the accommodating groove is used to accommodate the thin magnetic conductive ring (300); The length of the side plate (230) is greater than the radius of the arc portion (211) by more than 6 millimeters.
7. The leakage inductance tunable resonant transformer structure according to claim 5, characterized in that: A wiring groove (222) is provided on the side of the connection block (220); The primary lead wire of the primary coil of the primary winding (410) passes through the wiring groove (222) and is connected to the lead pin at the bottom of the support frame (200).
8. The leakage inductance tunable resonant transformer structure according to claim 1, characterized in that: It also includes a protective cover (600); the protective cover (600) is arranged in the main magnetic core group (100), and after the protective cover (600) wraps the primary winding (410), it extends in a direction away from the main magnetic core group (100) to increase the safety creepage distance.
9. The leakage inductance tunable resonant transformer structure according to claim 8, characterized in that: The protective cover (600) comprises a U-shaped annular plate (610), and flanges (620) respectively arranged at the top and bottom of the annular plate (610); the flanges (620) maintain an angle with the plate surface of the annular plate (610); A primary seat body for mounting the primary winding (410) is provided at the top of the support frame (200), and the two flanges (620) can be embedded in the primary seat body to ensure that the primary winding (410) and the secondary winding (420) have a safe distance.
10. The leakage inductance tunable resonant transformer structure according to claim 9, characterized in that: The flange (620) remains perpendicular to the plate surface of the annular plate (610).