On-board integrated transformer

Abstract

A vehicle-mounted integrated transformer includes: a magnetic core assembly, a main inductor coil, a secondary inductor coil, a transformer primary wire group and a transformer secondary winding. The magnetic core assembly includes a first magnetic core for the transformer and a second magnetic core for the inductor. The first magnetic core and the second magnetic core have a common magnetic path. The main inductor coil and the secondary inductor coil are integrated coils. The secondary inductor coil and the transformer primary wire group are interlaced. The secondary inductor coil and the transformer primary wire group are wound on the first magnetic core, and the main inductor coil is wound on the second magnetic core. The transformer secondary winding is electrically coupled with the transformer primary wire group and is located outside the transformer primary wire group. The present invention places the secondary conductor part that carries a large current on the outermost side to exchange with the air or the heat dissipation surface to achieve a high heat conduction efficiency. At the same time, the transformer leakage inductance principle is used to allow the resonant inductor and the transformer coil to be interlaced, so that the resonant inductor and the transformer are integrated for research and development.

Description

Technical Field

[0001] The invention relates to the field of transformers, and in particular to a vehicle-mounted integrated transformer. Background Art

[0002] At present, the magnetic components in the on-board charger are mostly made of resonant inductors and transformers separately, and the design concept is to wrap the coil with a magnetic core. Such products not only occupy space efficiency but also have low EMI effect. It is extremely inconvenient in converter circuit design and product assembly, making the overall size of the on-board charger large, the price high, and the power low, which restricts the further development of the new energy vehicle industrialization.

[0003] The on-board transformers in the prior art have the following disadvantages: a. They consist of many transformer and inductor modules, have low power density, complex structure and high cost; b. The product temperature rises, and the matching performance of the inductor and transformer is unstable; c. The products are scattered, the installation is cumbersome, and the installation space is large. Summary of the invention

[0004] The present invention provides a vehicle-mounted integrated transformer to solve any of the above technical problems.

[0005] To solve the above problems, as one aspect of the present invention, a vehicle-mounted integrated transformer is provided, comprising: a magnetic core assembly, a main inductor coil, a secondary inductor coil, a transformer primary wire group and a transformer secondary winding, the magnetic core assembly comprising a first magnetic core for a transformer and a second magnetic core for an inductor, the first magnetic core and the second magnetic core having a common magnetic circuit path, the main inductor coil and the secondary inductor coil are integrated coils, the secondary inductor coil and the transformer primary wire group are interlaced, the secondary inductor coil and the transformer primary wire group are wound on the first magnetic core, the main inductor coil is wound on the second magnetic core, the transformer secondary winding is electrically coupled with the transformer primary wire group and is located on the outside of the transformer primary wire group.

[0006] Preferably, the integrated coil is manufactured by continuous winding or external connection.

[0007] Preferably, the secondary winding of the transformer is a U-shaped copper sheet, and the primary wire group of the transformer is located in a U-shaped opening of the U-shaped copper sheet.

[0008] Preferably, the vehicle-mounted integrated transformer further comprises an assembly base plate, and the magnetic core assembly and the U-shaped copper sheet are both mounted on the assembly base plate.

[0009] Preferably, the magnetic core assembly includes two E-shaped magnetic cores, which are arranged opposite to each other and made of the same material. The two E-shaped magnetic cores are in full contact with each other, or have a single air gap, or have multiple air gaps.

[0010] Preferably, the magnetic core assembly comprises a structure in which a middle column magnetic core and side column magnetic cores made of the same material or different materials are combined, and the middle column magnetic core is arranged at the ends of the side column magnetic cores.

[0011] Preferably, the magnetic core assembly further comprises an I-shaped magnetic core piece arranged between the middle column magnetic core and the side column magnetic core.

[0012] Preferably, a single air gap or multiple air gaps are provided on the middle column of the middle column magnetic core.

[0013] Preferably, the side column magnetic core is composed of two U-shaped magnetic cores.

[0014] Preferably, the cross section of the middle column of the middle column magnetic core is rectangular, circular, or elliptical.

[0015] Due to the adoption of the above technical scheme, the present invention can utilize the relationship between the theoretical basis of thermal resistance and the thermal conductivity of the material, and change the design mode to place the secondary conductor part carrying large current on the outermost side to exchange with the air or the heat dissipation surface, so as to achieve the purpose of high heat conduction efficiency; at the same time, utilizing the transformer leakage inductance principle, the resonant inductor and the transformer coil are cross-wound, so that the resonant inductor and the transformer are developed and manufactured as an integrated whole, replacing the multiple magnetic components in the prior art to form an integrated transformer. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematically shows an exploded view of the present invention;

[0017] Figure 2 The schematic diagram of the structure of the transformer winding is shown schematically;

[0018] Figure 3 The schematic diagram of the structure of the inductor coil is shown schematically;

[0019] Figure 4 The schematic diagram shows the staggered arrangement structure of transformer windings and inductor coils;

[0020] Figure 5 A perspective view of the present invention is schematically shown;

[0021] Figure 6 A cross-sectional view of the present invention is schematically shown;

[0022] Figure 7 Schematically shows Figure 6 AA section view;

[0023] Figure 8 Schematically shows a top view of the present invention;

[0024] Fig. 9 Schematically shows Figure 8BB cross-sectional view;

[0025] Fig.10 The magnetic circuit structure diagram of the present invention is schematically shown;

[0026] Fig.11 The coil principle diagram of the present invention is schematically shown;

[0027] Fig.12 The circuit topology diagram of the integrated transformer in the OBC DC / DC is schematically shown;

[0028] Fig.13 The structural diagram of the magnetic core assembly is schematically shown.

[0029] The reference numerals in the figure are: 1. main inductor; 2. auxiliary inductor; 3. primary wire group of transformer; 4. secondary winding of transformer; 5. first magnetic core; 6. second magnetic core; 7. magnetic circuit path; 8. assembly base; 9. E-shaped magnetic core; 10. single air gap; 11. multi-section air gap; 12. middle column magnetic core; 13. side column magnetic core; 14. I-shaped magnetic core piece; 15. U-shaped magnetic core; 16. middle column. DETAILED DESCRIPTION

[0030] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0031] One aspect of the present invention provides a vehicle-mounted integrated transformer, which is particularly suitable for use in a vehicle-mounted charger.

[0032] The vehicle-mounted integrated transformer comprises: a magnetic core assembly, a main inductor 1, a secondary inductor 2, a transformer primary winding 3 and a transformer secondary winding 4. The magnetic core assembly comprises a first magnetic core 5 for a transformer and a second magnetic core 6 for an inductor. The first magnetic core 5 and the second magnetic core 6 have a common magnetic path 7. The main inductor 1 and the secondary inductor 2 are integrated coils. The secondary inductor 2 and the transformer primary winding 3 are interlaced so that the transformer leakage inductance reaches the required inductance. The secondary inductor 2 and the transformer primary winding 3 are wound on the first magnetic core 5, the main inductor 1 is wound on the second magnetic core 6, and the transformer secondary winding 4 is electrically coupled with the transformer primary winding 3 and is located outside the transformer primary winding 3. Preferably, the integrated coil is made by continuous winding or external connection. The magnetic core assembly forms multiple magnetic loops so that the inductor and the transformer magnetic loop are shared.

[0033] Please refer to Fig.10, the main magnetic circuit of the inductor is composed of three groups, namely aegd, befh, and cgfh. The main magnetic circuit of the abcd transformer is composed of abcd, and aegd is the transformer magnetic circuit diffusion circuit. It can be seen that the bhc magnetic circuit is a common path for the inductor and the transformer magnetic circuit, and abcd and aegd are common magnetic circuits for the inductor and the transformer. When the coil is wound, the main inductor coil and the auxiliary inductor coil are integrated coils, which can be wound continuously or connected externally, mainly providing inductance filtering.

[0034] Due to the adoption of the above technical scheme, the present invention can utilize the relationship between the theoretical basis of thermal resistance and the thermal conductivity of the material, and change the design mode to place the secondary conductor part carrying large current on the outermost side to exchange with the air or the heat dissipation surface, so as to achieve the purpose of high heat conduction efficiency; at the same time, utilizing the transformer leakage inductance principle, the resonant inductor and the transformer coil are cross-wound, so that the resonant inductor and the transformer are developed and manufactured as an integrated whole, replacing the multiple magnetic components in the prior art to form an integrated transformer.

[0035] Preferably, the transformer secondary winding 4 is a U-shaped copper sheet, and the transformer primary wire group 3 is located in the U-shaped opening of the U-shaped copper sheet, which can not only transform the voltage ratio, but also form a flat heat dissipation surface to expand heat dissipation. In this way, the present invention can use the copper sheet winding to dissipate heat over a large area and form a shielding effect for the circuit and the magnetic circuit, which greatly reduces the temperature rise, further improves EMI, greatly improves the work efficiency of the product, and has a significant reduction in volume and price compared with traditional products, thereby providing a new design concept for the further development of new energy vehicle OBC.

[0036] Preferably, the vehicle-mounted integrated transformer further comprises an assembly base plate 8 , and the magnetic core assembly and the U-shaped copper sheet are both mounted on the assembly base plate 8 .

[0037] Preferably, the magnetic core assembly includes two E-shaped magnetic cores 9, the E-shaped magnetic cores 9 are arranged opposite to each other and made of the same material, and the two E-shaped magnetic cores 9 are in full contact with each other (such as Fig.13 (a) in the figure), or a single air gap 10 is formed (such as Fig.13 (b) in the figure), or forming multiple air gaps 11 (such as Fig.13 (c) in the figure.

[0038] in, Fig.13 In the embodiment shown in (a), the same material core structure is used, the transformer and the inductor core are integrated, and a single core mold can be produced, and the main magnetic cross-section of the core is on both sides. Fig.13 In the embodiment shown in (b), a single air gap core structure of the same material is adopted, and the transformer and the inductor core are integrated, so that a single core mold can be produced. At the same time, an air gap is added to the core to correct the inductance, and the main magnetic cross-section of the core is on both sides. Fig.13In the embodiment shown in (c), a transformer and an inductor core are integrated using a segmented air gap core structure of the same material or different materials, so that a single core mold can be produced. At the same time, a segmented treatment is adopted for a large core air gap to reduce the magnetic cutting range and temperature at the air gap, and the main magnetic cross-section of the core is on both sides.

[0039] Please refer to Fig.13 In (d)-(g), preferably, the magnetic core assembly includes a structure in which a middle column magnetic core 12 and a side column magnetic core 13 of the same material or different materials are combined, and the middle column magnetic core 12 is arranged at the end of the side column magnetic core 13.

[0040] Preferably, the magnetic core assembly further includes an I-shaped magnetic core piece 14 (such as Fig.13 (d) in the figure.

[0041] Preferably, a single air gap 10 or multiple air gaps 11 are provided on the middle column of the middle column magnetic core 12 (eg Fig.13 (f) in the figure.

[0042] Preferably, the side column magnetic core 13 is composed of two U-shaped magnetic cores 15 (such as Fig.13 (g) in the figure.

[0043] Preferably, the cross section of the middle column 16 of the middle column magnetic core 12 is rectangular, circular, or elliptical.

[0044] in, Fig.13 In the embodiment shown in (d), a core structure of middle column and side column of the same material or different materials is adopted, the transformer and the inductor core are combined, the combined core can be glued, and the main magnetic cross section of the inductor core is in the middle, and the cross section of the middle column can be rectangular, circular, elliptical, etc. Fig.13 In the embodiment shown in (e), a structure of a middle column and side columns of the same material or different materials plus an I-piece magnetic core is adopted, the transformer and the inductor magnetic core are combined, the combined magnetic core can be glued, and the main magnetic cross section of the inductor magnetic core is in the middle, and the middle column cross section can be rectangular, circular, elliptical, etc. And an I-piece is added at the joint of the magnetic core to make the magnetic circuit guide smoother. Fig.13 In the embodiment shown in (f), a core structure with a middle column and side columns of the same material or different materials and an air gap is used, the transformer and the inductor core are combined, the combined core can be glued, and the main magnetic cross section of the inductor core is in the middle. The cross section of the middle column can be rectangular, circular, elliptical, etc., and the middle column can have a single air gap or multiple air gaps. Fig.13 In the embodiment shown in (g), the transformer core can be modified as follows using the magnetic core structure in df above: Fig.13 The structure shown in (g) is produced.

[0045] In the above Fig.13 In the embodiment shown, the magnetic core of the present invention can be made of two or the same magnetic material core combination to increase the power bearing capacity of the magnetic core and optimize the magnetic core loss; at the same time, the primary winding of the transformer and the inductor coil are wound using the staggered winding technology, which innovates the winding method of different functional windings and eliminates the hidden dangers of product joints; and the secondary functional winding of the transformer adopts a copper sheet structure to increase the surface heat dissipation area of ​​the coil. This integrated transformer is made through coil winding, core assembly, semi-finished product assembly, semi-finished product testing, glue dispensing, and finished product inspection processes. The finished product can easily meet the following effects: (1) This product realizes multi-functional integration by changing the magnetic core structure and optimizing the magnetic circuit design, reducing the overall noise of the product and reducing the overall power consumption; (2) Through the improvement of the winding process, the principle is rationally utilized and innovated, filtering and voltage transformation are realized, the heat dissipation area is increased, the product power is improved, and the product promotion ability is enhanced; (3) Through the comparison and selection of materials and the innovation of the winding process, it is achieved to save mineral resources such as iron ore and copper and aluminum ore materials, increase the guarantee of product electrical performance quality, and achieve the effect of energy saving and efficiency improvement. (4) In the DC / DC circuit of new energy vehicles, the temperature rise of this product in the whole machine can be completely controlled from the original 100K to within 70K, which extends the service life of the product. (5) The full load efficiency is increased from the original 90% to 97%.

[0046] The present invention has the following innovations:

[0047] (1) Changing the core structure, optimizing the magnetic circuit guidance route, forming a magnetic integration mode in which the resonant inductor and the transformer share the magnetic circuit, so that a single magnetic component has the functions of chopping control and voltage switching (chopping control corresponds to the inductor function, and the chopping control method for the rectifier circuit can filter and improve the power quality; voltage switching corresponds to the transformer part, which can provide the function of converting different voltages), achieving a year-on-year reduction in volume and cost;

[0048] (2) Based on the thermal conductivity of materials, and taking advantage of the higher thermal conductivity of copper than iron (copper is 401W / mK, iron is 80W / mK), we developed a copper-clad-iron design to form a high-efficiency, low-consumption mode and achieve high-efficiency energy-saving effects;

[0049] (3) Improve the shortcomings of the traditional coolant heat conduction surface that does not fit the magnetic components and the small conduction surface. Utilize the excellent electrical and thermal conductivity of the copper sheet to make the copper sheet into a U-shaped plane, so that it can become a conductive circuit while maximally fitting the coolant heat conduction surface, forming a complete fit between the magnetic heat dissipation surface and the coolant heat conduction surface, greatly taking away the heat, so that the transformer's original 4KW efficiency can be increased to 6.6KW, and the power of the product is greatly improved;

[0050] (4) The coil structure design adopts a double winding parallel winding mode. It also changes the traditional double-column transformer winding process, realizes the natural crossing of one wire winding between two columns, solves the hidden danger of the winding connection tap between the two columns breaking, and shortens the production time, improves product production efficiency, increases magnetic coupling, reduces leakage inductance and distributed capacitance, and can effectively suppress the electromagnetic interference caused by surge current, peak voltage and pulse top oscillation.

[0051] (5) Utilizing the transformer leakage inductance calculation principle, we innovated the interlaced winding of the transformer winding and the inductor winding, allowing the inductor coil to form a magnetic coupling relationship with the transformer primary coil, so that the inductance Lr and the transformer self-inductance Lm reach the required parameters, and innovated the inductor and transformer design and manufacturing technology to optimize the product performance.

[0052] The invention has the following advantages: 1) The product integrates multiple functions in one, achieving the effect of replacing multiple with one, and has the advantages of greater power, higher efficiency and simple structure. 2) The product simplifies the complex, accelerates the quantitative production, and the product has high stability and better performance. 3) The product uses an integrated module method, which makes the volume small and easy to install, and greatly reduces the volume of the whole machine. 4) Because the amount of raw materials used, such as iron and copper, is greatly reduced, the product cost is lower.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A vehicle-mounted integrated transformer, characterized in that: include: A magnetic core component, a main inductor coil (1), a secondary inductor coil (2), a transformer primary winding group (3) and a transformer secondary winding (4), wherein the magnetic core component comprises a first magnetic core (5) for a transformer and a second magnetic core (6) for an inductor, wherein the first magnetic core (5) and the second magnetic core (6) have a common magnetic circuit path (7), the main inductor coil (1) and the secondary inductor coil (2) are integrated coils to provide an inductance filtering function, the secondary inductor coil (2) and the transformer primary winding group (3) are interlacedly wound so that the resonant inductor and the transformer coil are cross-wound, so that the resonant inductor and the transformer are integrally manufactured, the secondary inductor coil (2) and the transformer primary winding group (3) are wound on the first magnetic core (5), the main inductor coil (1) is wound on the second magnetic core (6), and the transformer secondary winding (4) is electrically coupled with the transformer primary winding group (3) and is located outside the transformer primary winding group (3); The magnetic core assembly comprises two E-shaped magnetic cores (9), the E-shaped magnetic cores (9) are arranged opposite to each other and are made of the same material, the two E-shaped magnetic cores (9) are in full contact with each other, or form a single air gap (10), or form multiple air gaps (11); The magnetic core assembly comprises a structure in which a middle column magnetic core (12) and a side column magnetic core (13) made of the same or different materials are combined, and the middle column magnetic core (12) is arranged at the end of the side column magnetic core (13); The magnetic core assembly further comprises an I-shaped magnetic core piece (14) arranged between the middle column magnetic core (12) and the side column magnetic core (13); A single air gap (10) or multiple air gaps (11) are provided on the middle column of the middle column magnetic core (12); The transformer secondary winding (4) is a U-shaped copper sheet, and the transformer primary wire group (3) is located in a U-shaped opening of the U-shaped copper sheet.

2. The vehicle-mounted integrated transformer according to claim 1, characterized in that: The integrated coil is manufactured by continuous winding or external connection.

3. The vehicle-mounted integrated transformer according to claim 2, characterized in that: The on-vehicle integrated transformer also includes an assembly base plate (8), and the magnetic core assembly and the U-shaped copper sheet are both mounted on the assembly base plate (8).

4. The vehicle-mounted integrated transformer according to any one of claims 1 to 3, characterized in that: The side column magnetic core (13) is composed of two U-shaped magnetic cores (15).

5. The vehicle-mounted integrated transformer according to any one of claims 1 to 3, characterized in that: The cross section of the middle column of the middle column magnetic core (12) is rectangular, circular, or elliptical.

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