Electromagnetic device with improved refrigeration

Abstract

An electromagnetic device with improved refrigeration comprises a magnetic core (10). The utility model relates to a magnetic core (10) having at least one electrically conductive coil (20) and at least one slot (11) dividing the magnetic core into several separate magnetic core parts (10 '), and at least one cooling structure (30) comprising a heat sink (32) thermally connected to at least one thermally conductive element (31) comprising a flat wall made of a non-magnetic metal, the flat wall is tightly inserted into a gap of the magnetic core; the cooling structure further comprises a cooling channel connected to a cooling circuit, the cooling channel being defined in the heat sink and / or in a portion of at least one thermally conductive element of the cooling structure; and the cooling channel comprises a number of parallel bores (61) and at least one transverse bore (62) intersecting the number of parallel bores and interconnecting the number of parallel bores.

Description

TECHNICAL FIELD

[0001] The utility model relates to an electromagnetic device with improved refrigeration.

[0002] The electromagnetic device comprises a magnetic core with an electrically conductive coil wound around it. Improved refrigeration is obtained by at least one cooling structure comprising a heat conducting element in close contact with a heat sink, said heat conducting element being made of a non-magnetic material, said heat conducting element comprising a flat wall tightly inserted into a gap of the magnetic core, the gap dividing the magnetic core into two independent magnetic core parts. BACKGROUND

[0003] In order to try to remove the heat in the magnetic core of a magnetic unit, particularly in the case of power transformers, due to the generation of eddy currents, different methods have been tried. Some of these methods are: increasing the size of the wire to reduce the resistive losses; immersing the transformer in a circulating cooling oil; air cooling of the transformer windings; increasing the operating frequency of the transformer to reduce the winding; and increasing the thermal conductivity of the insulating potting compound surrounding the transformer windings. However, all these methods affect the mechanical size and weight of the transformer design, limiting the use of these applications. The efficiency and reliability of these transformers and inductors are greatly reduced without proper cooling.

[0004] DE19814896 discloses a power transformer for high currents with a closed cylindrical soft magnetic core made of a highly permeable material with a high saturation induction and low magnetic losses. A primary coil and a secondary coil are wound thereon. The magnetic core is located within a housing, which is then filled with a suitable resin. At least one heat pipe for cooling the unit is provided in the center. The heat pipe forms part of the transformer winding.

[0005] The contact surface between the tube and the magnetic core is reduced, so the cooling fluid needs to circulate through the duct to increase the cooling, which is more complex and makes the solution more expensive.

[0006] US6777835B1 discloses an electrical power cooling technology, particularly a device for cooling high power electrical transformers and electric motors, which provides a low resistant thermal path to the ambient environment by using a thermally conductive material interleaved between the turns layers of the high power transformer and between the core laminations. Strips direct the internal excess heat to protrusions outside the winding (and core), where forced air or thermally conductive potting compounds extract the heat. This technology significantly reduces weight and volume and enables a large increase in power density when operating at modestly elevated temperatures above the ambient environment. In one embodiment, the transformer is made of materials such as laminated iron, ferrites and other core materials, and the transformer is formed of insulated copper windings wound on the core. Heat is dissipated through the core to the base plate, and thermally conductive strips are placed in preselected locations between the windings, and the thermally conductive strips are preferably high modulus graphite laminates to conduct heat along the unidirectional fiber orientation thereof.

[0007] US2004257187A1 discloses an electromagnetic device comprising: a first tubular core section; a second tubular core section spaced apart from and aligned substantially parallel to the first tubular core section; and a primary conductive winding, wherein a first portion of the primary conductive winding is disposed within the first tubular core section and a second portion of the primary conductive winding is disposed within the second tubular core section. The magnetic device further comprises a heat extraction device having a conductive element, such as a cooling fin, in communication with at least a portion of an outer surface of the first tubular core section and at least a portion of an outer surface of the second tubular core section.

[0008] US2015155088A1 discloses a heat dissipation structure of a transformer for dissipating heat from a transformer core, the heat dissipation structure comprising a heat dissipation plate including a bottom plate mounted on a transformer housing, and an extension plate extending upwardly from the bottom plate. The extension plate includes a center plate and a pair of side plates located at opposite sides of the center plate. The pair of side plates are separated from the center plate.

[0009] CN113257545A relates to a high-power, high-efficiency, and high-heat-dissipation high-frequency transformer, which comprises an aluminum plate radiator containing a first aluminum plate, a second aluminum plate, and a third aluminum plate arranged in sequence.

[0010] GB2597670A1 relates to thermal management of electromagnetic devices such as transformers, comprising a core assembly, a winding, a primary heat plate, and a number of secondary heat plates.

[0011] All the above documents include a cooling structure on one side of the electromagnetic device, resulting in uneven cooling of the magnetic core.

[0012] The utility model solves above and other problems. Utility model content

[0013] The utility model relates to an electromagnetic device with improved refrigeration, as described below.

[0014] In a manner known from the current state of the art, the proposed electromagnetic device comprises:

[0015] a magnetic core having at least one electrically conductive coil wound around a central axis, the magnetic core comprising at least one gap parallel to the central axis, dividing the magnetic core into several independent magnetic core portions, and

[0016] at least one cooling structure, each cooling structure comprising a heat sink in thermal connection with at least one heat conducting element, each heat conducting element comprising a flat wall made of a non-magnetic metal, said flat wall being tightly inserted into one of the gaps of the magnetic core, in thermal connection with a magnetic core portion.

[0017] The heat conducting element is an element made of a non-magnetic material, which does not interfere with the magnetic field generated during operation of the electromagnetic device, and which has a high thermal conductivity, for example greater than 120 W / mK, greater than 160 W / mK, or preferably greater than 210 W / mK. Typically, the heat conducting element will be made of a non-magnetic metal such as aluminum or an aluminum alloy.

[0018] The tight contact between the heat conducting element and at least one heat dissipation surface of the magnetic core allows the transfer of the heat generated in the magnetic core during operation of the electromagnetic device to the heat conducting element.

[0019] In addition, the tight contact between the heat conducting element and the heat sink allows the transfer of said heat from the heat conducting element to the heat sink, where it is dissipated.

[0020] The heat sink will also be made of a material having a high thermal conductivity (for example greater than 120 W / mK, greater than 160 W / mK, or preferably greater than 210 W / mK). Typically, the heat sink will be made of a non-magnetic metal such as aluminum or an aluminum alloy.

[0021] The heat sink preferably comprises a heat dissipation configuration in contact with a cooling fluid (for example the surrounding air, but also a cooling liquid of a cooling circuit).

[0022] The heat dissipation configuration can comprise, for example, a surface provided with grooves, ribs, bars, or any other surface widening configuration intended to increase the exposed surface of the heat sink with respect to the cooling fluid.

[0023] Thermal connection should be understood as meaning: physical contact between the elements, allowing heat transfer between them via conduction; or contact through an intervening heat transfer medium (such as a heat transfer composition), allowing heat transfer between the elements via conduction through said heat transfer medium.

[0024] For example, a thermal connection exists between different parts of the same integral object, between two soldered parts, or between two overlapping surfaces without a gap, or between two overlapping surfaces without a gap but including a heat transfer composition therebetween to fill any imperfections and increase the overall thermal conductivity. The heat transfer composition is preferably a spreadable paste having a relevant thermal conductivity (e.g., greater than 5 W / mK, greater than 10 W / mK, or preferably greater than 40 W / mK).

[0025] According to the invention, the heat conducting element comprises a flat wall which is tightly inserted in a gap of the magnetic core, said gap dividing the magnetic core in at least two independent magnetic core portions. Preferably, said gap divides a region of the magnetic core which is surrounded by the electrically conducting coil, so that at least one heat conducting element is inserted in this region of the magnetic core surrounded by the electrically conducting coil.

[0026] According to this, the magnetic core will be divided in at least two independent magnetic core portions facing each other, a gap being defined between them, and it is proposed that the heat conducting element comprises at least one portion shaped as a flat wall which is tightly inserted in said gap between the at least two independent magnetic core portions of the magnetic core.

[0027] This configuration greatly increases the contact surface area between the heat dissipating magnetic core and the heat conducting element, improving the cooling of the electromagnetic device.

[0028] Preferably, the magnetic core portions face each other through respective heat dissipating surfaces, so that a gap will be defined between said heat dissipating surfaces. The heat conducting element will comprise two opposite main surfaces which are shaped in correspondence of the shape of the two opposite main surfaces of the flat wall, each surface being in tight contact with one of said heat dissipating surfaces.

[0029] The invention also proposes the following solutions in a non-exhaustive manner:

[0030] The cooling structure further comprises a cooling channel connected to the cooling circuit, the cooling channel being defined in a portion of the heat dissipating element of the heat dissipating structure and / or of the cooling structure; and

[0031] The cooling channel comprises a plurality of parallel holes and at least one cross hole which intersects those plurality of parallel holes so as to interconnect them.

[0032] The cooling channel can be connected to the cooling circuit, preferably comprising a cooling fluid pump.

[0033] At least some of the parallel holes can be blind holes defined in the at least one heat conducting element of the cooling structure. Said blind holes can comprise an inner wall tightly embedded therein, the inner wall longitudinally dividing the blind hole in two passages and defining a connection between the two passages at the bottom of the blind hole.

[0034] At least some of the cooling channels can be defined in the flat wall (when it is thick enough) inserted into the slot, or in portions of the heat conducting element outside the slot, which constitute an external heat conducting element, in thermal connection with the flat wall inserted tightly into the slot.

[0035] For example, it is proposed to contain the cooling channels in a thickened portion of the flat wall of the external heat conducting element inserted into the slot of the magnetic core, which is thicker than the flat wall of the external heat conducting element inserted into the slot of the magnetic core.

[0036] The shape of the thickened portion can be cylindrical, in thermal connection directly or through an intervening external heat conducting element shaped as a flat wall perpendicular to the flat wall inserted into the slot of the magnetic core, with the edges of the flat wall inserted into the slot of the magnetic core.

[0037] Optionally, the cooling structure can be divided into two halves, overlapping along the central axis direction, each half comprising one heat sink and portions of the heat conducting element in thermal connection with the respective heat sink. In this embodiment, the induction current is prevented from passing through the cooling structure by means of an electrically insulating body or air gap between the portions of the heat conducting element surrounded by the coil or between the portions of the cooling structure surrounding the coil.

[0038] According to the above, the cooling structure comprises at least two heat sinks, each heat sink being integrated on one half of the cooling structure, and at least one heat conducting element divided into at least two independent portions, each portion being in thermal connection with one heat sink.

[0039] The two halves of the cooling structure overlap along the central axis direction, so that the portions of the at least one heat conducting element of one half are separated from the portions of the other half by partitions transverse to the central axis direction.

[0040] Preferably, the at least one heat conducting element is inserted into the area of the magnetic core surrounded by the electrically conductive coil, and the cooling structure can also externally surround the electromagnetic device. In this case, if the cooling structure is made of an electrically conductive material, such as aluminum or an aluminum alloy, an undesirable induction current through the cooling structure can occur.

[0041] To prevent such an induction current, it should be avoided to have a circular electric circuit with the area surrounded by the electrically conductive coil. To prevent the induction current, the electrical connection between the portions of the at least one heat conducting element should be interrupted by an electrically insulating body or air gap in the area of the magnetic core surrounded by the electrically conductive coil.

[0042] In addition, or alternatively, the interruption of the electrical connection between the two halves of the cooling structure through the area of the cooling structure not surrounded by the electrically conductive coil can enable the interruption of the circular circuit, preventing the induction current. In this case, even if there is an electrical connection between the portions of the at least one heat conducting element surrounded by the electrically conductive coil, the induction current can be prevented.

[0043] According to one embodiment of the application, the flat walls comprised in the at least one heat conducting element are parallel to the central axis around which the at least one electrically conducting coil is wound.

[0044] The at least one heat conducting element can comprise several parallel heat conducting elements, the magnetic core being separated by at least two parallel slits.

[0045] Alternatively, the at least one heat conducting element can comprise one or more parallel heat conducting elements, the magnetic core being separated by at least two parallel slits, and one or more heat conducting elements perpendicular to the aforementioned heat conducting elements, the magnetic core being separated by at least one additional slit perpendicular to the aforementioned at least two parallel slits.

[0046] Each heat sink can for example be a housing containing the magnetic core, or a part of such a housing. The outer walls of the housing can for example be used as heat sinks, dissipating heat into the surrounding air.

[0047] The heat conducting elements can also comprise an external heat conducting element made of a non-magnetic metal and thermally connected to the heat sinks, close to the outside of the magnetic core, thermally connected to the magnetic core and / or to at least one flat wall tightly inserted in one slit of the magnetic core. According to this embodiment, the external heat conducting element is thermally connected to the outside of the magnetic core, directly or through an intervening heat transfer medium, dissipates heat from the outside of the magnetic core to the heat sinks, and / or is thermally connected to at least one flat wall tightly inserted in one slit of the magnetic core, helping the flat wall to dissipate heat from the inside of the magnetic core to the heat sinks.

[0048] The heat conducting elements and the heat sinks can be parts of an integral element constituting the cooling structure. This simplifies its manufacturing and improves the heat transfer between the heat conducting elements and the heat sinks.

[0049] Each half of the cooling structure can for example be made of a casted non-magnetic metal, a casted non-magnetic aluminum or a casted non-magnetic aluminum alloy. Manufacturing each half of the cooling structure by casting allows creating a custom shape adapted to increase heat dissipation and / or to reduce the manufacturing cost of the electromagnetic device, making its assembly easier and simpler. Preferably, each half of the cooling structure will have a shape that can be produced in a two-part mold.

[0050] Alternatively, each half of the cooling structure can be made of an extruded non-magnetic metal, an extruded non-magnetic aluminum or an extruded non-magnetic aluminum alloy, the extrusion direction being perpendicular to the central axis. In this case, the heat conducting element part of each half of the cooling structure should be one flat wall or several flat walls parallel to each other to allow manufacturing by extrusion, but the heat conducting element parts of the two halves of the cooling structure can be parallel or perpendicular to each other.

[0051] Manufacturing each half of the cooling structure by an extrusion process greatly increases the manufacturing speed, reduces the cost and allows to obtain a part with a high dimensional accuracy. In this case, the cooling structure will have a constant cross section along its entire length, or a constant cross section along its entire length after removal by milling along certain portions.

[0052] Aluminum and many of its alloys are known for being non-magnetic materials and having a high thermal conductivity.

[0053] According to the present invention, the heat sink is the housing of the electromagnetic device, or a part of the housing. According to this point, the electromagnetic device will be housed in a housing for protection, typically a rigid housing, the whole housing or a part thereof will constitute the heat sink, the heat conducting element being in close contact with said housing or a part thereof. The walls of the housing will dissipate heat, thus said walls are part of the cooling structure.

[0054] According to an embodiment of the present invention, the heat conducting composition surrounds the magnetic core and at least one coil wound around the magnetic core. The heat conducting composition will also be in close contact with one side of the heat sink to transfer heat from the heat conducting composition to the heat sink, preferably leaving the opposite side uncovered for heat dissipation. When the heat sink is the housing of the electromagnetic device or a part of the housing, the heat conducting composition will be housed in said housing, preferably poured therein.

[0055] Preferably, the heat conducting composition comprises a mixture of a silicone resin and at least a first filler, or a mixture of a silicone resin and a first filler comprising a natural mineral filler. Optionally, the heat conducting composition further comprises a second filler comprising aluminum hydroxide.

[0056] According to another embodiment, the magnetic core can further comprise a magnetic gap perpendicular to the slit to enhance the magnetic properties of the magnetic core, said magnetic gap completely dividing each individual magnetic core portion into two separate sections.

[0057] For example, the magnetic core can comprise a central region in the shape of a prism or a cylinder elongated in a direction parallel to the central axis, around which at least one coil is wound. Said central region of the magnetic core will be divided by the slit.

[0058] Optionally, the magnetic core further comprises a frame region surrounding a central opening in which the central region of the magnetic core is housed, connected at both ends to the frame region and bisecting the central opening. Said frame region of the magnetic core will also be divided by the slit.

[0059] The at least one coil can be wound around a bobbin interposed between the at least one coil and the magnetic core.

[0060] It will be appreciated that references to geometric positions such as parallel, perpendicular, tangent, etc. allow for a deviation of up to ±5° from the theoretically defined position of the term.

[0061] It will also be appreciated that any given range of values can not be optimal at the extreme values and that adjustments to the application can be required to make the extreme values workable, within the capabilities of those skilled in the art. BRIEF DESCRIPTION OF DRAWINGS

[0062] The above advantages and other features will be more fully understood from the following detailed description of an embodiment, taken with the drawings, which are by way of illustration only and not limitation, wherein:

[0063] Figure 1 A perspective exploded view of an electromagnetic device according to an embodiment is shown, in which the cooling structure comprises a heat sink, a heat conducting element comprising two mutually perpendicular flat walls inserted into two perpendicular slots of the magnetic core, and two thickened portions in the shape of a cylinder parallel to the central axis, attached to the ends of one of the flat walls, the cooling structure comprising a cooling channel through the heat sink and through said cylinder, generating active cooling of the cooling structure.

[0064] Figure 2 A perspective view of the electromagnetic device is shown, in which the magnetic core is separated by one slot parallel to the central axis and one gap perpendicular to the central axis, the view not including the cooling structure and the conducting composition. Figure 1

[0065] Figure 3 A perspective exploded view of an electromagnetic device according to an alternative embodiment is shown, similar to that shown in Figure 1 in which the cooling structure comprises two halves, the lower half being the same as described in Figure 1 and the upper half comprising an additional heat sink and two mutually perpendicular flat walls, the upper half having no cooling channel.

[0066] Figure 4 and Figure 5 A vertical cross-section of the heat conducting element is shown, coplanar with the central axis, as shown in Figure 3 Figure 4 A perspective view is shown, in which the heat conducting element is shown in exploded view, as shown in Figure 5

[0067] Figure 6 A perspective view is shown, similar to that shown in Figure 3 ​​​The exploded perspective view of the electromagnetic device according to an alternative embodiment is shown, wherein each half of the cooling structure includes a flat wall, and the lower half of the cooling structure includes four thickened portions of heat-conducting elements in four corner regions surrounding the magnetic core. The thickened portions are cylindrical in shape parallel to the central axis, and the cylinders are thermally connected to the ends of the flat walls by intervening external heat-conducting elements shaped as flat walls perpendicular to the flat walls inserted into the gaps in the magnetic core. The lower half also includes active cooling of the cooling structure through a heat sink and cooling channels through the cylinders. Detailed Implementation

[0068] This utility model relates to an electromagnetic device, including a magnetic core 10, a conductive coil 20 wound around the magnetic core 10 or a portion thereof around a central axis X, and a cooling structure 30 in close contact with the magnetic core 10.

[0069] The magnetic core 10 is composed of several independent magnetic core parts 10', which face each other through corresponding heat dissipation surfaces parallel to the central axis X, with a gap 11 defined between them.

[0070] The magnetic core 10 can also be separated by a magnetic gap 12 perpendicular to the central axis to improve the magnetic properties of the device.

[0071] For example, in Figure 3 In the embodiment shown, the magnetic core includes two slits 11 that are parallel to and perpendicular to each other with the central axis X, and a magnetic slit 12 that is perpendicular to the central axis, dividing the magnetic core 10 into eight magnetic core portions 10'.

[0072] The non-magnetic thermally conductive element 31 may include a cooling channel connected to a cooling circuit, preferably including a coolant pump. Optionally, the cooling channel may also be defined in a radiator.

[0073] At least some cooling channels may be defined in a flat wall (when it is thick enough) inserted into the slot 11, or may be defined in an external heat-conducting element that is thermally connected to the flat wall tightly inserted into the slot 11.

[0074] For example, it is suggested that a cooling channel be included in the thickened portion of the external heat-conducting element, which is thicker than the flat wall thickness inserted into the slot 11 of the magnetic core 10.

[0075] The thickened portion can be formed into a cylinder, and an external heat-conducting element, either directly or through intervention, is thermally connected to the edge of a flat wall inserted into the slot of the magnetic core 10. The external heat-conducting element is also formed into a flat wall perpendicular to the flat wall inserted into the slot 11.

[0076] The cooling channel may include a plurality of parallel holes 61 and at least one transverse hole 62, the transverse hole intersecting with and interconnecting the plurality of parallel holes 61.

[0077] Preferably, at least some of the parallel holes 61 are blind holes, generally parallel to the central axis X, defined in a portion of at least one thermally conductive element 31 of at least one half of the cooling structure 30. Each blind hole will comprise an inner wall 63 tightly inserted therein and connected with a cap, for example attached by threading to the open end of each blind hole, the inner wall 63 dividing the blind hole longitudinally into two passages and defining a connection between the two passages at the bottom of the blind hole, thus creating a cooling effect along the entire longitudinal direction of the blind hole.

[0078] Generally, the inner wall 63 is shorter than the blind hole in which it is inserted, or has a transverse opening at the distal end, creating said two parallel passages in each blind hole, one connected to one section of the transverse hole and the other to the other section of the transverse hole, forcing the cooling fluid towards the bottom of each blind hole.

[0079] According to one embodiment, the blind holes pass through the heat sink 32, having an open end on one side of the heat sink 32, opposite to the side of the heat sink connected to the thermally conductive element 32. Those parallel holes 61 are aligned on the area close to their open end and intersect with one transverse hole 62, which in this embodiment is coplanar and perpendicular to the parallel holes 61, said transverse hole passing completely through the attached heat sink 32.

[0080] The cooling structure 30 can comprise two halves overlapping in the direction of the central axis, each half comprising a heat sink 32 thermally connected to a portion of the thermally conductive element 31. Preferably, each half of the cooling structure is a single piece metal element obtained by a casting or extrusion operation or welded together.

[0081] One or both halves of the cooling structure can comprise cooling channels. For example, in the embodiment shown in Figure 3 and Figure 6 only the lower half of the cooling structure comprises a cooling circuit, but both halves can comprise a similar or symmetrical configuration with cooling channels.

[0082] The portion of the thermally conductive element 31 tightly inserted into the gap 11 is shaped as a flat wall in tight contact with the radiating surface of each individual core portion 10', i.e. each major surface of the flat wall is in tight contact with a radiating surface.

[0083] The non-magnetic thermally conductive element 31 of both halves of the cooling structure is interrupted by an air gap or by an electrical insulator, preventing electrical contact between both halves of the cooling structure through the portion inserted into the core 10 and surrounded by the electrically conductive coil 20.

[0084] According to Figure 2In the illustrated embodiment, each half of the heat sink 32 is shaped as an open-top box, forming part of the housing of the electromagnetic device, with a flat wall standing in its center, perpendicular to the bottom of the housing, said flat wall constituting part of the non-magnetic heat-conducting element 31 inserted into the magnetic core.

[0085] In the present embodiment, the electromagnetic device comprises two symmetrical cooling structures, each defining one half of the housing, so that when the electromagnetic device is assembled, the housing of the electromagnetic device is completely enclosed by the combination of the two heat sinks 32.

[0086] According to this first embodiment, the housing is filled with a heat-conducting composition 40, which surrounds the magnetic core 10 and the coil 20, through which the heat transfer from the magnetic core 10 to the heat sink 32 is also enhanced.

[0087] In a second embodiment, each half of the cooling structure comprises a heat sink 32, which defines only a bottom plate or a top plate, which can be part of the housing if additional walls are attached; or can be only a bottom plate or a top plate, for supporting all the components of the electromagnetic device, and facilitating its anchoring to a support by, for example, using screws through the through-holes provided on said bottom and top plates.

[0088] The plate can also contain only side walls parallel to the heat-conducting element on its two sides, said side walls providing a safer housing than a simple bottom plate, and can be produced together with the flat wall by an extrusion process.

[0089] According to the second embodiment, the heat-conducting composition 40 is molded and hardened between the heat sinks of the cooling structure 30.

[0090] Optionally, each half of the cooling structure comprises at least one flat wall and two side walls parallel to said at least one flat wall, wherein the flat wall and the side walls of one half are perpendicular to the flat wall and the side walls of the other half, so that the two side walls of one half and the other two side walls of the other half can completely enclose the device between four side walls and two heat sinks, while each half is manufactured by extrusion in an inexpensive and simple manner.

[0091] According to a preferred embodiment, the magnetic core comprises a central region, elongated along the direction of the central axis X, housed within the central opening of the frame region, and connected to said frame region by its ends. The electrically conductive coil 20 is wound around the central region, for example on a bobbin 50 interposed between the coil 20 and the central region of the magnetic core 10.

[0092] The central region can be cylindrical, or prismatic in shape, such as cubic.

[0093] In both embodiments, the slot 11 divides vertically the central region and the frame region into halves, but in the first embodiment the slot 11 divides horizontally the frame region into two C-shaped portions, while in the second embodiment the slot 11 divides longitudinally the frame region into two thinner frames, each half of the heat conducting element having an E-shape, not only inserted into the central region of the magnetic core, but also between the thinner frames. In this case, each half of the heat conducting element 31 has an upper edge, distal from the heat sink 32 to which it is connected, having an E-shaped profile, defining one central protrusion inserted into the central region of the magnetic core, and two side protrusions inserted into the frame region of the magnetic core distal from the central region. This embodiment can be seen in Figure 4 and Figure 5 .

[0094] In both embodiments, the magnetic gap 12 divides horizontally the central region and the frame region into two halves.

Claims

1. An electromagnetic device with improved cooling, comprising: A magnetic core (10) having at least one conductive coil (20) wound around a central axis (X), the magnetic core (10) including at least one slit (11) parallel to the central axis (X), dividing the magnetic core (10) into several independent core portions (10'), and At least one cooling structure (30), each cooling structure including a heat sink (32) thermally connected to at least one thermally conductive element (31), each thermally conductive element (31) including a flat wall made of non-magnetic metal, the flat wall being tightly inserted into a slot (11) of the magnetic core (10) and thermally connected to the magnetic core portion (10'); Its features are, The cooling structure (30) further includes a cooling channel connected to a cooling circuit, the cooling channel being defined in the radiator and / or in a portion of at least one thermally conductive element (31) of the cooling structure (30); and The cooling channel includes a plurality of parallel holes (61) and at least one transverse hole (62), wherein the at least one transverse hole intersects with the plurality of parallel holes (61) and interconnects the plurality of parallel holes.

2. The electromagnetic device according to claim 1, characterized in that, At least some of the parallel holes (61) are blind holes defined in at least one heat-conducting element (31) of the cooling structure (30) and include an inner wall (63) tightly inserted therein, the inner wall (63) dividing the blind hole longitudinally into two channels and defining the connection between the two channels at the bottom of the blind hole.

3. The electromagnetic device according to claim 1, characterized in that, The at least one thermally conductive element (31) includes a plurality of parallel and / or vertical thermally conductive elements (31).

4. The electromagnetic device according to claim 2, characterized in that, The at least one thermally conductive element (31) includes a plurality of parallel and / or vertical thermally conductive elements (31).

5. The electromagnetic device according to any one of claims 1 to 4, characterized in that, At least some of the cooling channels are defined in a flat wall tightly inserted into the slit (11), or in portions of a heat-conducting element defined outside the slit (11), forming an external heat-conducting element thermally connected to the flat wall tightly inserted into the slit (11).

6. The electromagnetic device according to any one of claims 1 to 4, characterized in that, Each heat sink (32) is a housing that at least partially houses the magnetic core (10), or a portion thereof.

7. The electromagnetic device according to any one of claims 1 to 4, characterized in that, The thermally conductive element (31) further includes at least one external thermally conductive element that is adjacent to and thermally connected to the exterior of the magnetic core (10), the external thermally conductive element being made of a non-magnetic metal and thermally connected to the heat sink (32) and / or thermally connected to the flat wall that is tightly inserted into one of the gaps of the magnetic core.

8. The electromagnetic device according to any one of claims 1 to 4, characterized in that, The radiator (32) and the thermally connected heat-conducting element (31) are single components made of cast metal, cast aluminum or cast aluminum alloy, or single components made of extruded metal, extruded aluminum or extruded aluminum alloy extruded in a direction perpendicular to the central axis (X).

9. The electromagnetic device according to any one of claims 1 to 4, characterized in that, The cooling structure (30) is divided into two overlapping halves along the central axis (X) direction. Each half includes a heat sink (32) and a portion of the heat-conducting element (31) thermally connected to the corresponding heat sink (32). Induced current is prevented from passing through the cooling structure (30) by electrical insulators or air gaps located between multiple portions of the heat-conducting element (31) surrounded by the coil (20) and / or between multiple portions of the cooling structure (30) surrounding the coil (20).

10. The electromagnetic device according to claim 9, characterized in that, Each half of the cooling structure (30) is a single-piece element made of extruded metal, extruded aluminum or extruded aluminum alloy extruded in a direction perpendicular to the central axis (X), with the flat wall of one half perpendicular to the flat wall of the other half.

11. The electromagnetic device according to claim 10, characterized in that, Each half of the cooling structure also includes two sidewalls adjacent to the outer side of the magnetic core (10) and parallel to the flat wall.

12. The electromagnetic device according to any one of claims 1 to 4, characterized in that, The magnetic core (10) and the at least one conductive coil (20) are embedded in a thermally conductive composition (40), which is in thermal contact with each heat sink (32).

13. The electromagnetic device according to claim 12, characterized in that, The thermally conductive composition comprises: A mixture of silicone resin and at least a first filler, or a mixture of silicone resin and a first filler comprising natural mineral fillers; or A mixture of silicone resin and at least a first filler, or a mixture of silicone resin and a first filler containing natural mineral filler, and a second filler containing aluminum hydroxide.

14. The electromagnetic device according to any one of claims 1 to 4, characterized in that, The magnetic core also includes a magnetic gap (12) perpendicular to the central axis (X) for enhancing the magnetic properties of the magnetic core (10), the magnetic gap (12) completely dividing each individual magnetic core part (10') into two separate segments.

15. The electromagnetic device according to any one of claims 1 to 4, characterized in that, The at least one coil (20) is wound on a spool (50) between the at least one coil (20) and the magnetic core (10).

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