Transformer and power conversion equipment

Abstract

The utility model provides a transformer and power conversion equipment. The transformer comprises a magnetic core assembly and a flat plate winding, the flat plate winding comprises a plurality of flat plate coils, at least one metal pipe extending in the circumferential direction of the coil is welded to at least one side of at least one of the flat plate coils, and a cooling medium is arranged in the at least one metal pipe; the plurality of flat coils are stacked in the length direction of a central column of the magnetic core assembly, and the central column penetrates through central holes of the plurality of flat coils. Through the structure that the metal pipe is welded to at least one side of the flat coil, the cooling medium channel is directly integrated in the winding heating area, and compared with a traditional external radiator scheme, the heat dissipation efficiency of the transformer is improved.

Description

Technical Field

[0001] This utility model relates to the field of transformer technology, and in particular to a transformer and power conversion equipment. Background Technology

[0002] Transformers are an important component of power conversion equipment. Among the existing types of transformers, wound transformers are mainly constructed with enameled copper wire or copper foil windings. Due to the bottleneck of heat dissipation efficiency, this type of product is only suitable for low-power products. For products with high power density, the heat dissipation efficiency is very low due to structural limitations. Utility Model Content

[0003] The purpose of this utility model embodiment is to provide a transformer and power conversion equipment to solve the problem of low heat dissipation efficiency of existing transformers.

[0004] To achieve the above objectives, this utility model provides a transformer, including: a magnetic core assembly and a flat plate winding;

[0005] The flat winding includes a plurality of flat coils, and at least one side of at least one flat coil is welded with at least one metal tube extending along the circumferential direction of the coil, and a cooling medium is disposed inside the at least one metal tube.

[0006] The plurality of flat coils are stacked along the length of the central post of the magnetic core assembly, and the central post passes through the central hole of the plurality of flat coils.

[0007] This utility model embodiment also provides a power conversion device, which includes the transformer provided in this utility model embodiment.

[0008] One of the above technical solutions has the following advantages or beneficial effects:

[0009] In this embodiment of the invention, the transformer includes a magnetic core assembly and a planar winding. The planar winding includes multiple planar coils, and at least one side of at least one of the multiple planar coils is welded with at least one metal tube extending along the circumferential direction of the coil. A cooling medium is disposed inside the at least one metal tube. The multiple planar coils are stacked along the length of the central post of the magnetic core assembly, and the central post passes through the central hole of the multiple planar coils. This embodiment of the invention, by welding a metal tube to at least one side of the planar coil, directly integrates the cooling medium channel into the heating area of ​​the winding, improving the heat dissipation efficiency of the transformer compared to traditional external heat sink solutions. Attached Figure Description

[0010] Figure 1This is a schematic diagram of the structure of a transformer provided in an embodiment of the present utility model;

[0011] Figure 2 This is a schematic diagram of the structure of a single flat coil provided in an embodiment of this application;

[0012] Figure 3 This is a schematic diagram of the structure of a connector provided in one embodiment of this application;

[0013] Figure 4 This is a schematic diagram of the connection method of the magnetic core provided in an embodiment of this application. Figure 1 ;

[0014] Figure 5 This is a schematic diagram of the connection method of the magnetic core provided in an embodiment of this application. Figure 2 ;

[0015] Figure 6 This is a schematic diagram of the structure of a magnetic core assembly provided in an embodiment of this application;

[0016] Figure 7 This is a schematic diagram of the structure of the metal tube input and output terminals provided in an embodiment of this application. Detailed Implementation

[0017] To make the technical problems, technical solutions and advantages of this utility model clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0018] like Figure 1 As shown, this utility model embodiment provides a transformer, such as Figure 1 As shown, it includes: a magnetic core assembly 11 and a flat winding;

[0019] The flat winding includes a plurality of flat coils 12, and at least one side of at least one flat coil 12 is welded with at least one metal tube 13 extending along the circumferential direction of the coil, and the at least one metal tube 13 is provided with a cooling medium inside.

[0020] The plurality of flat coils 12 are stacked along the length of the central post of the magnetic core assembly 11, and the central post passes through the central hole of the plurality of flat coils 12.

[0021] In this embodiment of the utility model, Figure 1The structural form is illustrated by example. Of course, the above-mentioned magnetic core assembly 11 and flat winding can have any structure and shape, provided that the basic functions are met. This utility model embodiment does not limit this. Among them, the above-mentioned magnetic core assembly 11 is the core component that forms the magnetic circuit in the transformer, and its central column passes through the central hole of the flat winding. The flat winding includes a plurality of flat coils 12 stacked along the axial direction of the magnetic core central column. At least one side of at least one flat coil 12 is welded with a metal tube 13 extending circumferentially along the coil, and the interior of the metal tube 13 is filled with a cooling medium.

[0022] The magnetic core assembly 11 described above serves to provide a closed magnetic circuit for conducting magnetic field energy. Its material can be silicon steel sheet, amorphous alloy, or nanocrystalline material. This embodiment of the invention does not specifically limit the shape, quantity, or stacking method of the magnetic core. The stacking method of the flat coils 12 can be flexibly designed according to heat dissipation requirements, for example, using equal-spaced stacking or a gradually varying spacing arrangement.

[0023] The metal tube 13 and the flat coil 12 described above can be welded using laser welding, brazing, or electron beam welding, forming an integrated structure for mechanical fixation and heat conduction through the weld seam. The layout of the metal tube 13 includes, but is not limited to, spiral winding, concentric ring, or wavy extension, to meet different heat dissipation path requirements. For the selection of the cooling medium, insulating oil, liquid metal, or deionized water can be used, and this embodiment of the invention does not impose specific limitations on this. In some optional embodiments, the metal tube 13 itself can also serve as part of the winding conductor.

[0024] The design of the central post penetrating the central hole of the flat coil 12 enables the magnetic core assembly 11 and the flat winding to form a coaxial assembly relationship. In some optional embodiments, the cross-sectional shape of the central post can match the central hole of the flat coil 12, for example, by adopting a circular, rectangular, or polygonal structure, thereby optimizing the magnetic circuit closure effect and enhancing mechanical stability.

[0025] Furthermore, in this embodiment of the invention, the specific structural design of each flat coil 12 is not specifically limited in terms of the number of coil turns or the conductor cross-sectional area, so as to... Figure 2The structure of the planar coil 12 is illustrated using an example. Of course, the planar coil 12 can have any structure and shape while meeting basic functional requirements. It should be noted that each planar coil 12 can be used as a primary or secondary coil according to user needs. For example, in a transformer with 10 layers of stacked planar coils 12, the user can select layers 1-3 as primary coils connected to the input power supply, and layers 4-10 as secondary coils connected to the load, or configure them in reverse according to voltage transformation requirements. The axial spacing between the planar coils 12 is adjustable, for example, by adjusting the thickness of the stacking spacers. The user can optimize magnetic coupling efficiency according to the power distribution requirements of the primary or secondary coils. For example, alternating the primary and secondary planar coils 12 can shorten the magnetic path distance to improve efficiency (suitable for high-frequency transformers). Alternatively, in scenarios requiring high isolation voltage, the spacing between the primary and secondary coil groups can be increased to reduce leakage inductance.

[0026] This embodiment of the invention integrates the cooling medium channel directly into the heating area of ​​the winding by welding a metal tube 13 to at least one side of the flat coil 12, which improves the heat dissipation efficiency of the transformer compared with the traditional external heat sink solution.

[0027] As an optional implementation method, Figure 6 As shown, the magnetic core assembly 11 includes a first part and a second part with a symmetrical structure. Each of the first part and the second part includes n magnetic cores 14. The n magnetic cores 14 are fixedly connected side by side to form a closed magnetic circuit, where n is a positive integer greater than or equal to 1.

[0028] In this implementation, Figure 6 The structural form is illustrated by an example. Of course, the magnetic core assembly 11 can have any structure and shape while meeting the basic functions. The magnetic core assembly 11 is divided into a symmetrical first part and a second part. The first part and the second part are connected by a magnetic yoke to form a seamless ring magnetic circuit. The two parts are mirror symmetrical in geometry, size, and arrangement of the magnetic cores 14. The symmetrical layout ensures that the magnetic flux is evenly distributed in the magnetic core, reducing the risk of leakage and local magnetic saturation. Figure 4 and Figure 5For example, the aforementioned n magnetic cores 14 fixedly connected side-by-side to form a closed magnetic circuit can be understood as n magnetic cores 14 arranged side-by-side along the same plane in the horizontal or vertical direction, forming a whole through physical connections such as bonding, welding, or bolting. This embodiment of the invention does not specifically limit the arrangement method. By increasing or decreasing the number of magnetic cores 14, for example, n can be chosen as 2, 4, 6, etc., the cross-sectional area of ​​the magnetic cores can be dynamically adjusted, thereby reducing magnetic resistance. Furthermore, combining magnetic cores 14 of different materials or sizes can optimize the overall performance of the transformer. In some optional embodiments, the magnetic core assembly 11 adopts a slot-type frame, allowing the magnetic cores 14 to be plugged in and replaced, and damaged individual cores can be replaced individually, thus reducing maintenance costs.

[0029] This embodiment of the invention improves the uniformity of magnetic flux distribution through the mirror-symmetrical first and second parts. The closed magnetic circuit design eliminates magnetic circuit breaks, reducing magnetic reluctance and iron losses, such as eddy current losses and hysteresis losses. Simultaneously, the n-value can be adjusted in real time according to load requirements. The power capacity can be adjusted based on specific application scenarios by increasing or decreasing the number of magnetic cores (n-value), thereby improving the transformer's versatility. Furthermore, this embodiment of the invention does not specifically limit the material type of the magnetic core. For example, the magnetic core can be a manganese-zinc ferrite core, but other types of magnetic cores are also possible.

[0030] Of course, the aforementioned magnetic core assembly 11 can also adopt an asymmetrical structure or other structures, and the magnetic core assembly 11 can also be composed of three or more magnetic core segments. The number of magnetic cores contained in each segment is not limited in this embodiment. For example, a three-segment E-type magnetic core can be adapted to multi-winding transformer topologies. Different structures and materials of the magnetic core assembly 11 do not affect the realization of the basic functions of the transformer of this invention.

[0031] As an optional implementation, an insulating layer is provided between adjacent flat coils 12, the insulating layer comprising at least one insulating film, the insulating film being disposed between each flat coil 12 in a wrapping and winding manner.

[0032] In this embodiment, the aforementioned insulating layer is used to isolate adjacent coils and prevent short circuits or high-voltage breakdown. The material of the insulating film is not specifically limited in this embodiment; for example, polyimide (PI) film, polyetheretherketone (PEEK) film, or ceramic fiber composite film can be used. In some optional embodiments, a silicone rubber film doped with microcapsules can also be used. When the film cracks due to mechanical stress, the capsules rupture and release liquid siloxane repair agent to automatically fill the defect. Furthermore, a certain proportion of boron nitride (BN) or aluminum oxide (Al2O3) particles can be added to the insulating film to form heat-conducting channels.

[0033] Regarding the specific process of the aforementioned wrapping and winding, this embodiment of the invention does not limit the scope. Multi-layer composite winding can be used, alternating winding of films of different materials, such as alternating winding of a layer of polyimide film and a layer of mica tape or other materials, utilizing the complementary properties of the materials to achieve pressure resistance and high-temperature resistance. Oriented winding technology can also be used, for example, winding the film at a certain angle (any angle, such as 45 degrees) along the edge of the coil, eliminating the gaps of traditional parallel winding and thus improving coverage. Furthermore, in some optional embodiments, the insulating film can be pre-impregnated with epoxy resin, wound, and then heated and cured to form a rigid insulating layer that is tightly adhered to the coil surface, thereby preventing interlayer displacement. The aforementioned at least one insulating film can be understood to encompass single-layer, multi-layer, composite, and functionally modified layers; this embodiment of the invention does not specifically limit the scope of these.

[0034] In some optional embodiments, corrugated or honeycomb-shaped elastic interlayers can be provided between the thin film layers to absorb the mechanical stress generated by the thermal expansion and contraction of the coil, so as to better adapt to vibration conditions. In addition, the embodiments of this utility model do not specifically limit the color and transparency of the thin film. A semi-transparent fluorescent film can be used, which can show the location of cracks under ultraviolet light, making it easy to detect the insulation status.

[0035] In this embodiment, by providing an insulating layer between adjacent flat coils 12, the film continuously covers the coil edge (easily discharged area) in a wrapping and winding manner, reducing the risk of gap breakdown compared to traditional laminated insulation. Furthermore, the thickness of the insulating film is smaller than that of the insulating pad, achieving synergistic optimization for transformer miniaturization while maintaining high insulation performance.

[0036] Of course, in addition to insulating films, other materials or other forms of insulating layers can be used to achieve the insulation effect. For example, ceramic or glass fiber-based materials can be covered on the coil surface through spraying, sintering, or bonding processes; synthetic mica paper can also be wrapped around the coil surface and then vacuum impregnated with insulating varnish, etc. In other alternative embodiments, gaps can be formed between each flat coil 12, or the flat coil 12 can be encapsulated in an inert gas environment, which can replace the addition of an insulating layer to achieve the insulation effect.

[0037] As an optional implementation, a cooling system connected to the at least one metal pipe 13 is also included. The cooling system includes a circulating pump, a heat exchanger, and a liquid storage tank. The outlet of the circulating pump is connected to the inlet of the at least one metal pipe 13 via at least one connector, the inlet of the heat exchanger is connected to the outlet of the at least one metal pipe 13 via at least one connector, and the liquid storage tank is connected in series between the outlet of the heat exchanger and the inlet of the circulating pump.

[0038] In this embodiment, the circulating pump is used to drive the cooling medium to circulate in the system. The specific selection of the circulating pump is not limited in this embodiment; centrifugal pumps, frequency converters, or gear pumps can be used depending on the transformer's flow and pressure requirements. The heat exchanger is used to transfer the heat of the cooling medium in the metal tube 13 to the external environment. The specific type of heat exchanger is also not limited in this embodiment; air-cooled, water-cooled, or plate heat exchangers can be used. The liquid storage tank can be understood as a container used to store and stabilize the cooling medium in the system. In some optional embodiments, the liquid storage tank may include a level gauge, a safety relief valve, and a pressure valve. The material and type of the liquid storage tank are also not limited in this embodiment. For example, expansion tanks, open-type liquid storage tanks, or liquid storage tanks made of corrosion-resistant materials can be used. The connecting parts can be integrated manifold blocks, parallel valves, or elastic snap-fit ​​diversion modules. The selection of different types of connecting parts does not affect the realization of the basic functions of the transformer in this embodiment; therefore, this embodiment does not specifically limit this. The input and output ends of the metal tube are... Figure 7 Examples of structural forms are given, but not limited to these. Figure 7 The listed structural forms do not specifically limit the exact locations of the input and output terminals on the metal tube in this embodiment of the invention.

[0039] In this embodiment, the cooling medium is driven by a circulating pump to increase the convective heat transfer coefficient. The volume change of the medium is buffered by a liquid storage tank, and rapid cooling is achieved in conjunction with the heat exchanger to avoid local hot spots, thereby improving the heat dissipation efficiency and reliability of the transformer.

[0040] Of course, composite phase change materials, such as paraffin and graphene, can be filled inside the metal tube 13, and a radiant heat sink can be integrated into the transformer shell. The radiant heat sink is connected to the metal tube 13 through thermally conductive silicone grease. Alternatively, liquid metal can be used as a cooling medium, and an axial electric field can be applied to the liquid metal to generate a Lorentz force. The liquid metal circulates under the drive of electromagnetic force, or other methods that do not require mechanical pumps can be used to replace the cooling system consisting of a circulating pump, heat exchanger, and liquid storage tank, and to remove heat to the environment.

[0041] As an optional implementation, the at least one connecting member is a parallel valve, which includes a flow divider / combiner valve body, a connecting pipe, an inner tube, and a threaded locking structure.

[0042] The flow divider and manifold valve body includes a flow divider chamber and a manifold chamber. The flow divider chamber is connected to the input end of the at least one metal pipe 13 through at least one flow divider channel, and the manifold chamber is connected to the output end of the at least one metal pipe 13 through at least one manifold channel.

[0043] A connecting pipe is provided at the connection point between the diversion channel and the input end of the at least one metal pipe 13, and at the connection point between the confluence channel and the output end of the at least one metal pipe 13.

[0044] like Figure 3 As shown, the embedded tube is inserted into the input and output ends of at least one metal tube 13 with an interference fit. The threaded locking structure is sleeved on the outer wall of the embedded tube, and the internal thread of the threaded locking structure is screwed into the external thread of the connecting tube.

[0045] In this embodiment, the aforementioned diversion cavity is used to evenly distribute the cooling medium from the circulating pump to the input ends of each metal tube 13, and the aforementioned manifold cavity is used to collect the high-temperature medium from the output ends of each metal tube 13 and guide it centrally to the heat exchanger. The number of the aforementioned diversion channels and manifold channels matches the number of the aforementioned metal tubes 13. The aforementioned connecting pipe serves as a transition interface between the diversion channels and manifold channels and the metal tubes 13, providing mechanical support and ensuring sealing. The specific material of the connecting pipe is not specifically limited in this embodiment. The aforementioned embedded tube is inserted into the end of the metal tube 13 through an interference fit, achieving a leak-free hard connection. This can enhance the tensile strength at the interface and prevent vibration-induced detachment. In some optional embodiments, the sealing performance can be improved by nickel plating or epoxy resin coating on the surface of the embedded tube. The aforementioned threaded locking structure clamps the embedded tube and the connecting pipe by screwing in the internal and external threads.

[0046] For example, the flow splitting process can be that the cooling medium enters the flow splitting chamber from the outlet of the circulating pump, and the flow splitting chamber distributes the medium to the input end of each metal pipe 13 through multiple flow splitting channels. The end of the flow splitting channel is connected to the input end of the metal pipe 13 through a connecting pipe. The flow combining process can be that the high-temperature medium carrying heat enters the flow combining channel from the output end of the metal pipe 13 through the connecting pipe. The flow combining channel gathers multiple media into the flow combining chamber, and the outlet of the flow combining chamber is connected to the inlet of the heat exchanger to complete the circulation closure.

[0047] In this embodiment, by using parallel valves as connectors, flow equalization control of 13 multi-metal pipes can be achieved in a compact space, while long-term reliability is ensured through threaded locking and interference fit.

[0048] Of course, an integral metal block, such as aluminum or stainless steel, can be used, with internal milling of diversion and convergence channels, and each branch interface using flanges or sealing surfaces to form an integrated manifold block; alternatively, an elastic snap-fit ​​diversion module can be used, such as a diversion base made of nylon injection molding, a silicone sealing ring with a pre-embedded groove, a spring steel snap-fit ​​quick locking mechanism, and an annular groove machined at the end of the metal pipe 13. The snap-fit ​​is pressed into the groove to achieve self-sealing, replacing the parallel valve to achieve the connection of the cooling system of the metal pipe 13. Using different connectors does not affect the realization of the basic function of the transformer in this utility model embodiment.

[0049] As an optional implementation, it also includes a packaging assembly, which includes upper and lower metal cover plates, which are fixedly connected by at least one connector to press the magnetic core assembly 11.

[0050] In this embodiment, the upper and lower metal cover plates clamp and fix the magnetic core assembly 11 by at least one connector to prevent magnetic core displacement or air gap changes caused by electromagnetic vibration. In some optional embodiments, the surface of the metal cover plates can be anodized or nickel-plated to improve the corrosion resistance of the encapsulated assembly. An insulating layer can also be pre-placed on the inner side of the cover plates to prevent short circuits. The specific material and shape of the metal cover plates are not specifically limited in this embodiment, as long as they meet the basic encapsulation function. The connectors provide a detachable rigid connection, allowing for quick disassembly and assembly during maintenance. They also distribute the clamping force evenly, avoiding localized stress concentration in the magnetic core. The specific type of connector is not specifically limited in this embodiment; bolts, snap-locking mechanisms, etc., can be used.

[0051] In this embodiment, the detachable compression packaging design ensures the stability of the magnetic core while improving the convenience and reliability of transformer maintenance.

[0052] Of course, whether or not there is a packaging component, or whether other types of materials or different methods are used for packaging, does not affect the realization of the basic function of the transformer in this utility model embodiment. In this regard, this utility model embodiment does not make specific limitations.

[0053] As an optional implementation, the upper and lower metal cover plates are provided with heat dissipation holes.

[0054] In this embodiment, heat dissipation holes are provided on the surface of the metal cover plate. The hole structure accelerates natural air convection or forced air cooling. The location and size of the openings are not specifically limited in this embodiment. For example, circular, hexagonal, or oblong holes can be used. The specific distribution can be uniform, gradient, or honeycomb. Different types of heat dissipation holes do not affect the realization of the basic function of this embodiment.

[0055] By adding heat dissipation holes to the surface of the aforementioned metal cover plate, airflow can be optimized, improving the heat dissipation capacity of the encapsulated components, thereby enhancing the heat dissipation capacity of the transformer. In some optional embodiments, a removable filter screen can be installed on the outside of the holes, or a self-cleaning airflow backflushing device can be added to the inside of the metal plate to prevent the heat dissipation holes from becoming clogged.

[0056] Of course, fins can be added to the metal cover to increase the heat dissipation area, or a high thermal conductivity coating, such as graphene or ceramic coating, can be used to improve heat conduction, or other heat dissipation methods can be used to replace the heat dissipation holes to achieve the heat dissipation function of the metal cover. Whether or not heat dissipation holes are provided on the surface of the upper and lower metal cover does not affect the realization of the basic function of the transformer in the embodiment of this utility model.

[0057] As an optional implementation, the plurality of flat coils 12 adopt a copper foil structure.

[0058] In this embodiment, the eddy current loss of the copper foil structured flat coil 12 is low. The present invention does not specifically limit the processing technology used for the flat coil 12. For example, in some optional embodiments, a copper foil lamination process can be used to reduce the thickness of the flat coil 12, thereby improving space utilization. Photochemical etching, cold spraying, and other processes can also be used.

[0059] Of course, in some other alternative embodiments, aluminum-copper composite foil stacked structure, superconducting graphene coil or liquid metal structure can be used instead of copper foil. The flat coil 12 made of different materials does not affect the realization of the basic function of the transformer in this utility model embodiment.

[0060] As an optional implementation, a positioning pin is provided between adjacent flat coils 12, the positioning pin penetrating the insulation layer and interfering with the positioning hole of the central post.

[0061] In this embodiment, the aforementioned positioning pins ensure precise alignment between coils and prevent displacement. An interference fit may provide better mechanical stability. This embodiment does not specifically limit the material, type, size, or arrangement of the positioning pins, as long as the basic positioning function is met. In some optional embodiments, the positioning pins on the different flat coils 12 can be evenly distributed along the circumference of the central column or asymmetrically distributed to prevent common-mode interference. The aforementioned interference fit offers higher rigidity than traditional bolt fixing. A chamfered structure can also be added to the positioning hole on the central column, or thermally conductive silicone grease can be filled at the interference fit. Since the positioning pins penetrate the insulating layer, surface treatments such as anodizing can be applied to the positioning pins to maintain insulation.

[0062] The locating pins between adjacent flat coils 12 penetrate the insulation layer and are interference-fitted with the locating holes of the central column, thereby forcibly constraining the radial and tangential displacement of adjacent coils. This ensures that the distance between coil layers is fixed as required. The interference fit further limits the displacement that the flat coils 12 may generate when the transformer is working, and enables "blind insertion" assembly without the need for other alignment equipment. The locating pins improve the stability and reliability of the transformer while also enhancing the ease of assembly.

[0063] Of course, a wedge-shaped interlocking structure, a magnetic positioning system, or a thermal expansion self-locking structure can also be used to replace the positioning pin to achieve the positioning function of the flat coil 12. This embodiment of the invention does not specifically limit this. Furthermore, whether or not a positioning pin is added does not affect the realization of the basic function of the transformer in this embodiment of the invention.

[0064] In this embodiment of the invention, the transformer includes a magnetic core assembly 11 and a planar winding. The planar winding includes multiple planar coils 12, and at least one side of at least one of the multiple planar coils 12 is welded with at least one metal tube 13 extending along the circumferential direction of the coil. A cooling medium is disposed inside the at least one metal tube 13. The multiple planar coils 12 are stacked along the length of the central post of the magnetic core assembly 11, and the central post passes through the central hole of the multiple planar coils 12. This embodiment of the invention, by welding a metal tube 13 to at least one side of the planar coil 12, directly integrates the cooling medium channel into the heating area of ​​the winding, improving the heat dissipation efficiency of the transformer compared to traditional external heat sink solutions.

[0065] In addition, this utility model embodiment also provides a power conversion device including a transformer of any implementation provided in this utility model embodiment.

[0066] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the utility model involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

[0067] Apart from the technical features described in the specification, the other technical features are known to those skilled in the art. To highlight the innovative features of this utility model, the other technical features will not be described in detail here.

Claims

1. A transformer, characterized by The power conversion device comprises: a magnetic core assembly and a flat-plate winding; the flat-plate winding comprises a plurality of flat-plate coils, at least one side of at least one flat-plate coil of the plurality of flat-plate coils is welded with at least one metal pipe extending in a circumferential direction of the coil, and the at least one metal pipe is internally provided with a cooling medium; the plurality of flat-plate coils are arranged in a stacking manner along a length direction of a center column of the magnetic core assembly, and the center column penetrates through a center hole of the plurality of flat-plate coils.

2. The transformer of claim 1, wherein, the magnetic core assembly comprises a first part and a second part in a symmetrical structure, each of the first part and the second part comprises n magnetic cores, the n magnetic cores are fixedly connected side by side to form a closed magnetic circuit, and n is a positive integer greater than or equal to 1.

3. The transformer of claim 2, wherein, an insulating layer is arranged between adjacent flat-plate coils, the insulating layer comprises at least one insulating film, and the insulating film is arranged between each flat-plate coil in a cladding winding manner.

4. The transformer of any one of claims 1 to 3, wherein, a cooling system connected with the at least one metal pipe is further included, the cooling system comprises a circulating pump, a heat exchanger and a liquid storage tank, an outlet of the circulating pump is communicated with an input end of the at least one metal pipe through at least one connecting piece, an inlet of the heat exchanger is communicated with an output end of the at least one metal pipe through at least one connecting piece, and the liquid storage tank is connected in series between an outlet of the heat exchanger and an inlet of the circulating pump.

5. The transformer of claim 4, wherein, the at least one connecting piece is a parallel valve, the parallel valve comprises a shunt and confluence valve body, a connecting pipe, an embedded pipe and a threaded locking structure; the shunt and confluence valve body comprises a shunt cavity and a confluence cavity, the shunt cavity is communicated with the input end of the at least one metal pipe through at least one shunt channel, and the confluence cavity is communicated with the output end of the at least one metal pipe through at least one confluence channel; the connecting pipe is arranged at a connection between the shunt channel and the input end of the at least one metal pipe, and at a connection between the confluence channel and the output end of the at least one metal pipe; the embedded pipe is inserted into the input end and the output end of the at least one metal pipe in an interference fit, the threaded locking structure is sleeved on an outer wall of the embedded pipe, and an internal thread of the threaded locking structure is screwed with an external thread of the connecting pipe.

6. The transformer of any one of claims 1 to 3, wherein, a packaging assembly is further included, the packaging assembly comprises upper and lower metal cover plates, the upper and lower metal cover plates are fixedly connected through at least one connecting piece, and the magnetic core assembly is compressed.

7. The transformer of claim 6, wherein the upper and lower metal cover plates are provided with heat dissipation holes on surfaces thereof.

8. The transformer of any one of claims 1 to 3, wherein, the plurality of flat-plate coils adopt a copper foil structure.

9. The transformer of claim 3, wherein, a positioning pin is arranged between adjacent flat-plate coils, the positioning pin penetrates through the insulating layer and is in interference fit with a positioning hole of the center column.

10. A power conversion device, characterized by, the power conversion device comprises the transformer according to any one of claims 1 to 9.

Images