Main transformer and resonant inductor integrated structure

Abstract

The invention discloses a main transformer and resonant inductor integrated structure which comprises the following components: a main transformer which comprises a primary winding, a secondary winding and a transformer magnetic core; the resonant inductor comprises a resonant inductor winding and a resonant inductor magnetic core; the differential mode inductor comprises a differential mode inductor winding and a differential mode inductor magnetic core; wherein the resonant inductor winding is connected to the primary winding, and the differential mode inductor winding is connected to the secondary winding. Therefore, high integration of the main transformer, the resonant inductor and the differential mode inductor is realized, the differential mode inductor of the resonant inductor can be effectively increased on the premise of not increasing too much cost and volume, the suppression capability of the resonant inductor on differential mode interference is improved, the anti-interference capability of a system is improved, and the stability and reliability of a power electronic system are improved; the problems that in the prior art, a magnetic element is large in size, high in cost, insufficient in anti-interference capacity and the like are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic magnetic components, and in particular to an integrated structure of a main transformer and a resonant inductor. Background Art

[0002] In modern power electronic devices, such as switching power supplies and inverters, the main transformer and resonant inductor are key magnetic components. Traditionally, these components are implemented as separate components. This separate design presents numerous challenges: Firstly, it occupies significant circuit board space, hindering device miniaturization and integration; secondly, the use of multiple independent components increases system cost and complexity, potentially exacerbating electromagnetic interference (EMI).

[0003] The continuous advancement of power electronics technology is placing higher demands on the performance and integration of magnetic components. Magnetic integration of the main transformer and resonant inductor has become an important approach to addressing these challenges. However, while existing magnetic integration designs have reduced size and cost to a certain extent, they still lack performance optimization. For example, in resonant inductors, how to effectively increase the differential mode inductance to improve differential mode interference suppression while maintaining the original performance of the main transformer and resonant inductor remains a pressing technical challenge.

[0004] Differential-mode interference (DMI) is a common form of electromagnetic interference (EMI) in power electronics systems. It can cause current and voltage fluctuations in circuits, disrupting normal operation and potentially damaging electronic components. Traditional methods for suppressing DMI, such as adding separate DM inductors, increase component count and cost, increase size, and impact overall circuit layout and performance.

[0005] Therefore, it is necessary to study a new technical solution to solve the above problems. Summary of the Invention

[0006] In view of this, the present invention addresses the deficiencies in the prior art, and its main purpose is to provide an integrated structure of a main transformer and a resonant inductor, which can effectively increase the differential mode inductance of the resonant inductor without increasing excessive cost and volume, thereby improving the system's anti-interference capability and solving the problems of large magnetic component volume, high cost, and insufficient anti-interference capability in the prior art.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A main transformer and resonant inductor integrated structure, comprising: base; A main transformer comprising a primary winding, a secondary winding and a transformer core; A resonant inductor, comprising a resonant inductor winding and a resonant inductor magnetic core; A differential mode inductor, comprising a differential mode inductor winding and a differential mode inductor core; The resonant inductor and the differential mode inductor are respectively arranged at two opposite side ends of the main transformer and are both provided on the base; the resonant inductor winding is connected to the primary winding, and the differential mode inductor winding is connected to the secondary winding.

[0008] As a preferred solution, the base is provided with a first mounting cavity and a second mounting cavity arranged side by side with a spacing; the main transformer and the resonant inductor are arranged side by side in the first mounting cavity, and the differential mode inductor is arranged in the second mounting cavity.

[0009] As a preferred solution, the transformer core and the resonant inductor core are assembled adjacent to each other, and the differential mode inductor core maintains a distance from the transformer core.

[0010] As a preferred solution, a CT winding is added to the differential mode inductor, and the CT winding is connected to the output separately.

[0011] As a preferred embodiment, the transformer core includes two first E-type cores assembled facing each other, and the resonant inductor core includes a second E-type core, the open end of the second E-type core faces the closed end of the first E-type core of the transformer core, so as to form an accommodation area for accommodating the resonant inductor winding.

[0012] As a preferred solution, the differential mode inductor core includes two third E-shaped cores assembled facing each other.

[0013] As a preferred solution, the secondary winding is divided into two groups connected in series, the differential mode inductor winding is connected to the series connection point, and the other ends of each of the two groups serve as two endpoint outputs.

[0014] As a preferred solution, it also includes: A first busbar copper sheet connects one end pin of the two sets of secondary windings in series and is connected to one end pin of the differential mode inductor winding; A second busbar copper sheet connects the other end pins of a group of secondary windings in series; The third bus copper sheet connects the other end pins of another set of secondary windings in series.

[0015] As a preferred solution, the bottom surface of the base is designed as a stepped surface, and the first bottom end surface below the first installation cavity is higher than the second bottom end surface below the second installation cavity.

[0016] As a preferred solution, a plurality of connection pins and a plurality of pin holes are provided on the outside of the base corresponding to the first installation cavity and the second installation cavity.

[0017] Compared with the prior art, the present invention has obvious advantages and beneficial effects. Specifically, it can be seen from the above technical scheme that the main method is to connect the resonant inductor winding to the primary winding and the differential mode inductor winding to the secondary winding. The resonant inductor and the differential mode inductor are respectively arranged at two opposite side ends of the main transformer and are both set on the base, thereby achieving high integration of the main transformer, the resonant inductor and the differential mode inductor. Without increasing too much cost and volume, the differential mode inductance of the resonant inductor can be effectively increased, the suppression ability of the resonant inductor on the differential mode interference can be improved, the anti-interference ability of the system can be improved, the stability and reliability of the power electronic system can be improved, and the problems of large volume, high cost and insufficient anti-interference ability of magnetic components in the prior art can be solved.

[0018] In order to more clearly illustrate the structural features and effects of the present invention, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a perspective view of an integrated structure of a main transformer and a resonant inductor according to an embodiment of the present invention; Figure 2 is another perspective view of an integrated structure of a main transformer and a resonant inductor according to an embodiment of the present invention; Figure 3 is an exploded view of an integrated structure of a main transformer and a resonant inductor according to an embodiment of the present invention; Figure 4 This is a front view of a main transformer and resonant inductor integrated structure in an exploded state according to an embodiment of the present invention; Figure 5 This is a front view of an integrated structure of a main transformer and a resonant inductor in an assembled state according to an embodiment of the present invention; Figure 6 is a cross-sectional view of an integrated structure of a main transformer and a resonant inductor according to an embodiment of the present invention; Figure 7 is a detailed exploded diagram of a main transformer and resonant inductor integrated structure according to an embodiment of the present invention; Figure 8 is a cross-sectional view of a differential mode inductor winding and a secondary winding of a main transformer according to an embodiment of the present invention; Figure 9 1. It is a diagram showing the circuit connection relationship between the main transformer, resonant inductor, and differential mode inductor according to an embodiment of the present invention; Figure 10 This is a three-dimensional diagram of an actual application of a main transformer and resonant inductor integrated structure according to an embodiment of the present invention; Figure 11 This is another three-dimensional diagram of an actual application of a main transformer and resonant inductor integrated structure according to an embodiment of the present invention. DETAILED DESCRIPTION

[0020] Please refer to Figures 1 to 11 As shown, it shows the specific structure of an embodiment of the present invention.

[0021] In the description of the present invention, it should be noted that the terms "up", "down", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the present invention.

[0022] A main transformer and resonant inductor integrated structure achieves "resonant inductor + main transformer + differential mode inductor" reintegration, including a base 10 and a main transformer 20, a resonant inductor 30, and a differential mode inductor 40 disposed on the base 10. By integrating the main transformer 20, the resonant inductor 30, and the differential mode inductor 40 on the base 10, they can be pre-assembled and tested as a module, simplifying the assembly process of the final product and improving production efficiency and consistency.

[0023] The base 10 is an injection-molded component, equipped with a first mounting cavity 11 and a second mounting cavity 12 arranged side by side. The base 10 serves as the mechanical support for the entire integrated structure, providing a reference for component positioning and securing. Heat dissipation slots 13 are typically provided through the bottoms of both the first and second mounting cavities 11, 12. The base 10 has a stepped bottom surface, with the first bottom end surface 16 of the first mounting cavity 11 higher than the second bottom end surface 15 of the second mounting cavity 12. The base 10 also provides heat dissipation, dissipating heat from the main transformer 20, resonant inductor 30, and differential mode inductor 40.

[0024] The main transformer 20 includes a primary winding 21, a secondary winding 22, and a transformer core 23. Both the primary winding 21 and the secondary winding 22 have several sub-windings that are alternately arranged and wound in layers, which helps reduce primary-secondary coupling interference. Each sub-winding can be made of enameled wire. During production, the enameled wire is installed on winding equipment, and winding parameters such as winding speed and tension are adjusted to ensure uniformity and stability during the winding process. The wire is then wound into a coil and insulated, such as by coating with insulating varnish, to improve the insulation and moisture resistance of the sub-windings. The main transformer 20 is primarily used to achieve electrical isolation and voltage conversion between input and output. In the application circuit, the primary winding 21 is generally connected to the input power supply or inverter bridge arm. The secondary winding 22 can also be connected to the output rectifier circuit as needed. The transformer core 23 provides the main magnetic flux path and is commonly made of materials such as ferrite, nanocrystalline, and amorphous alloys.

[0025] The resonant inductor 30 comprises a resonant inductor winding 31 and a resonant inductor core 32. The transformer core 23 and the resonant inductor core 32 are assembled adjacent to each other. The resonant inductor winding 31 carries the resonant current, while the resonant inductor core 32 provides the inductor magnetic circuit, physically and magnetically integrated with the transformer core 23. In an application circuit, it is typically connected in series with the primary winding 21 (for example, between the inverter bridge output and the primary winding 21).

[0026] The differential-mode inductor 40, comprising a differential-mode inductor winding 41 and a differential-mode inductor core 42, is primarily used to suppress differential-mode noise on the output side (or input side). Differential-mode noise is interference signals between the output positive and negative lines (or the input live and neutral lines). The differential-mode inductor utilizes a separate core to avoid electromagnetic effects caused by magnetic coupling. The differential-mode inductor core 42 is spaced apart from the transformer core 23. Furthermore, placing the differential-mode inductor 40 closest to the secondary output shortens the high-frequency noise path and enhances EMI suppression. The differential-mode inductor winding 41 is preferably a flat copper wraparound sheet with a rectangular cross-section, such as a rectangle. The differential-mode inductor winding 41 is connected in series with the output loop of the secondary winding 22 of the main transformer 20 (for example, between the rectifier output of the secondary winding 22 and the output filter capacitor / load). The differential-mode inductor core 42 provides an inductive magnetic circuit and typically has an air gap to prevent DC bias saturation.

[0027] The resonant inductor 30 and the differential-mode inductor 40 are respectively arranged at two opposite sides of the main transformer 20 and are both mounted on the base 10. Furthermore, the main transformer 20 and the resonant inductor 30 are arranged side by side within the first mounting cavity 11, and the differential-mode inductor 40 is disposed within the second mounting cavity 12. Thus, by physically integrating three independent magnetic components (the main transformer 20, the resonant inductor 30, and the differential-mode inductor 40) into a single base 10, significant PCB or system space is saved, making installation and positioning easy and reliable, and space-compact. The resonant inductor 30 and the differential-mode inductor 40 are respectively arranged at two opposite sides of the main transformer 20. This layout fully utilizes the space on both sides of the main transformer 10, resulting in a more organized layout. This centralized layout also facilitates the unified installation of heat sinks or air cooling measures, providing a common, low-thermal-resistance heat dissipation path, thereby facilitating overall temperature rise control. It should be noted that during actual assembly, after placing the main transformer 20, resonant inductor 30, and differential mode inductor 40 into the base 10, ensure that the positions of each component are accurate, and then use glue or other fixing methods to firmly connect the main transformer 20, resonant inductor 30, and differential mode inductor 40 to the base 10. This usually also involves gluing and fixing the magnetic core assembly and the coil assembly.

[0028] The resonant inductor winding 31 is connected to the primary winding 21, and the differential inductor winding 41 is connected to the secondary winding 22. Furthermore, a CT winding 43 is added to the differential inductor 40, and the CT winding 43 is separately wired and output to the PCB. Two sets of differential inductor windings 41 are provided, and two sets of CT windings 43 are provided, located at opposite ends of the two sets of differential inductor windings 41. The two sets of differential inductor windings 41 are arranged close together to facilitate the placement of their differential inductor winding pins 411. The careful layout design and winding connection of the base 10, main transformer 20, resonant inductor 30, and differential inductor 40 facilitates the reduction of loop stray inductance (such as resonant loop inductance) during high-frequency operation. Placing the differential inductor 40 on the output side, close to where filtering is required, helps improve its noise suppression effectiveness.

[0029] In this embodiment, the transformer core 23 includes two first E-type cores assembled in opposite directions, and the resonant inductor core 32 includes a second E-type core. The open end of the second E-type core faces the closed end of the first E-type core of the transformer core 23, thereby forming an accommodation area for the resonant inductor winding 31. This achieves a magnetic integration design of the resonant inductor core 32 and the transformer core 23, that is, the first E-type core of the transformer core 23 provides a foundation for the resonant inductor core 32. The magnetic center columns of the transformer core 23 and the resonant inductor core 32 are coaxially arranged in opposite directions, for example, in opposite directions. The differential mode inductor core 42 includes two third E-type cores assembled in opposite directions. These E-shaped cores are arranged vertically, and the bottom end surface of the E-shaped core can be used for installation and positioning. At the same time, the front and back sides of the center column can be connected to the outside world. Compared with the horizontal E-shaped core, it is easier to position, and the front and back sides of the center column are open and not blocked by installation and positioning, which is conducive to better heat dissipation.

[0030] The secondary winding 22 is divided into two groups connected in series, and the differential-mode inductor winding 41 is connected to the series connection point, with the other ends of each winding serving as two output terminals. Considering the electrical connection between the main transformer, resonant inductor, and differential-mode inductor, the integrated structure of the main transformer and resonant inductor further includes a plurality of busbars, for example, four, specifically a first busbar 51, a second busbar 52, a third busbar 53, and a fourth busbar 54, wherein: The first bus copper sheet 51 connects one end pins of the two groups of secondary windings 22 in series and is connected to one end pin of the differential mode inductor winding 41; specifically, one group of secondary windings 22 includes a number of sub-windings, and the two pins of each sub-winding are located in the upper row and the middle row respectively, while the other group of secondary windings 22 includes a number of sub-windings, and the two pins of each sub-winding are located in the lower middle row and the middle row respectively, thus forming an upper, middle and lower row of pin arrangements, each pin is connected to a connecting piece 1 with a slot, and the first bus copper sheet 51 is used to connect the pins 212 in the middle row in series, and one end of the first bus copper sheet 51 passes through the slots of each connecting piece 1 in the middle row, is welded and fixed to form a reliable electrical connection; the pins of the differential mode inductor winding 41 are all connected to the plug-in piece 2, and a first slot is provided at the other end of the first bus copper sheet 51 for the plug-in piece 2 to be embedded. Similarly, mechanical fixation and reliable electrical connection can be achieved during the welding process.

[0031] The second bus copper sheet 52 connects the other end pins of a group of secondary windings 22 in series; specifically, the second bus copper sheet 52 passes through the notches of each connecting sheet in the upper row.

[0032] The third bus copper sheet 53 connects the other end pins of another set of secondary windings 22 in series; specifically, the third bus copper sheet 53 passes through the notches of the connecting sheets in the lower row.

[0033] The fourth bus copper sheet 54 is connected to the other end pin of the differential mode inductor winding 41 . Specifically, the insert is embedded in the second slot of the fourth bus copper sheet 54 .

[0034] The base 10 is provided with a plurality of connection pins and a plurality of pin holes 14 on the outside of the first and second mounting cavities 11 and 12. The connection pins include: the main transformer connection pins 211 to which the two end pins of the primary winding 21 of the main transformer 20 are connected; the resonant inductor connection pin 311 to which one end pin of the resonant inductor winding 31 is connected; and the differential inductor connection pin 431 to which the two end pins of the differential inductor winding 41 are connected. The other end pin of the resonant inductor winding 31 is connected to one of the main transformer connection pins 211. Three pin holes 14 are provided, which are respectively used to insert and position the pins 521 at the lower end of the second busbar 52, the pins 531 at the lower end of the third busbar 53, and the pins 541 at the lower end of the fourth busbar 54. Spare connection pins may also be reserved on the base 10. These connection pins and pin holes are all integrally provided on the base 10 during injection molding, and are arranged close to the respective locations of the main transformer 20 , the resonant inductor 30 , and the differential mode inductor 40 for easy connection.

[0035] The key design point of the present invention is that it mainly connects the resonant inductor winding to the primary winding and the differential mode inductor winding to the secondary winding. The resonant inductor and the differential mode inductor are respectively arranged at two opposite side ends of the main transformer and are both set on the base, thereby achieving a high degree of integration of the main transformer, the resonant inductor, and the differential mode inductor. It can effectively increase the differential mode inductance of the resonant inductor without increasing too much cost and volume, improve the resonant inductor's ability to suppress differential mode interference, improve the system's anti-interference ability, enhance the stability and reliability of the power electronic system, and solve the problems of large size, high cost, and insufficient anti-interference ability of magnetic components in the prior art. Specifically: 1. Small size and low cost: By integrating the main transformer and resonant inductor into a magnetic core structure, the number of components and circuit board space occupied are reduced, reducing the size and cost of the equipment. The integrated design also simplifies the circuit layout and assembly process, improving production efficiency.

[0036] 2. Performance Optimization: Adding differential-mode inductance to the resonant inductor effectively improves the ability to suppress differential-mode interference, enhancing the stability and reliability of the power electronics system. This approach is easy to implement and facilitates further optimization. For example, the design of a left-right assembled core structure and a flat, multi-piece, left-right stacked winding design allow for coordinated optimization of the performance of the main transformer and resonant inductor by optimizing the core structure and winding coil parameters, thereby improving the efficiency and power density of the entire system.

[0037] 3. Good compatibility: The design of the present invention has good compatibility and can be seamlessly connected with existing power electronic circuits and equipment without the need for large-scale transformation of the original system, thus reducing application costs and technical risks.

[0038] The above description is merely a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any minor modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A main transformer and resonant inductor integrated structure, characterized in that: Includes: Base (10); A main transformer (20) comprising a primary winding (21), a secondary winding (22) and a transformer core (23); A resonant inductor (30), comprising a resonant inductor winding (31) and a resonant inductor magnetic core (32); A differential mode inductor (40), comprising a differential mode inductor winding (41) and a differential mode inductor magnetic core (42); The resonant inductor (30) and the differential mode inductor (40) are respectively arranged at two opposite side ends of the main transformer (20), and are both provided on the base (10); the resonant inductor winding (31) is connected to the primary winding (21), and the differential mode inductor winding (41) is connected to the secondary winding (22).

2. The main transformer and resonant inductor integrated structure according to claim 1, characterized in that: The base (10) is provided with a first installation cavity (11) and a second installation cavity (12) arranged side by side with a spacing; the main transformer (20) and the resonant inductor (30) are arranged side by side in the first installation cavity (11), and the differential mode inductor (40) is arranged in the second installation cavity (12).

3. A main transformer and resonant inductor integrated structure according to claim 1 or 2, characterized in that: The transformer magnetic core (23) and the resonant inductor magnetic core (32) are assembled adjacent to each other, and the differential mode inductor magnetic core (42) maintains a distance from the transformer magnetic core (23).

4. The main transformer and resonant inductor integrated structure according to claim 1, characterized in that: A CT winding (43) is added to the differential mode inductor (40), and the CT winding (43) is connected and output separately.

5. The main transformer and resonant inductor integrated structure according to claim 1, characterized in that: The transformer core (23) includes two first E-shaped cores assembled facing each other, and the resonant inductor core (32) includes a second E-shaped core, wherein an open end of the second E-shaped core faces a closed end of the first E-shaped core of the transformer core (23), thereby forming an accommodation area for accommodating the resonant inductor winding (31).

6. A main transformer and resonant inductor integrated structure according to claim 1 or 5, characterized in that: The differential mode inductor magnetic core (42) comprises two third E-shaped magnetic cores assembled facing each other.

7. The main transformer and resonant inductor integrated structure according to claim 1, characterized in that: The secondary winding (22) is divided into two groups connected in series, the differential mode inductor winding (41) is connected to the series connection point, and the other ends of each of the two groups serve as two endpoint outputs.

8. The main transformer and resonant inductor integrated structure according to claim 7, characterized in that: Also included are: A first busbar copper sheet (51) connects one end pin of two sets of secondary windings (22) in series and is connected to one end pin of the differential mode inductor winding (41); A second busbar copper sheet (52) connects the other end pins of a set of secondary windings (22) in series; The third bus copper sheet (53) connects the other end pins of another set of secondary windings (22) in series.

9. The main transformer and resonant inductor integrated structure according to claim 1, characterized in that: The bottom surface of the base (10) is designed as a stepped surface, and the first bottom end surface (16) below the first installation cavity (11) is higher than the second bottom end surface (15) below the second installation cavity (12).

10. The main transformer and resonant inductor integrated structure according to claim 9, characterized in that: A plurality of connection pins and a plurality of pin holes (14) are provided on the base (10) on the outsides of the first installation cavity (11) and the second installation cavity (12) corresponding to the first installation cavity (11).

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