Electromagnetic device with improved refrigeration

Abstract

An electromagnetic device with improved refrigeration, comprising: a magnetic core (10) having at least one electrically conductive coil (20) wound around the magnetic core about a central axis (X); and at least one cooling structure (30) comprising a thermally conductive element (31) in intimate contact with a heat sink (32) constituting an enclosure of the electromagnetic device, the thermally conductive element (31) in intimate contact with at least one dissipative surface of the magnetic core (10); wherein the thermally conductive element (31) is a flat wall tightly inserted in a slot (11) of the magnetic core (10), which slot divides the magnetic core into two separate magnetic core parts, the enclosure comprising two halves, each half comprising a heat sink (32), and wherein an air gap or an electrical insulator interrupts the non-magnetic thermally conductive element (31), in this way, electrical contact between the two halves of the enclosure is prevented.

Description

Technical Field

[0001] The present invention relates to an electromagnetic device with improved refrigeration.

[0002] The electromagnetic device includes a magnetic core having an electrically conductive coil wound therearound. Improved cooling is achieved by at least one cooling structure comprising a thermally conductive element made of a non-magnetic material in close contact with a heat sink, the thermally conductive element including flat walls that fit snugly into a gap in the magnetic core, the gap dividing the core into two separate core sections. Background Art

[0003] Different approaches have been tried to remove heat (generated by the generated Foucault currents) from the cores of magnetic power cells, particularly in the case of power transformers. Some of these include increasing wire size to reduce resistive losses; immersing the transformer in circulating cooling oil; air cooling the transformer windings; increasing the transformer's operating frequency to reduce winding losses; and increasing the thermal conductivity of the insulating potting compound surrounding the transformer windings. However, all of these have an impact on the mechanical size and weight of the transformer design, limiting its use in these applications. Without proper cooling, the efficiency and reliability of these transformers and inductors are significantly reduced.

[0004] Patent document DE19814896 discloses a power transformer for high currents having a closed cylindrical core made of a soft magnetic, high-permeability material, high saturation induction, and low magnetic losses. This is wound with a primary coil and a secondary coil. The core is enclosed in a housing which is subsequently filled with a suitable resin. At least one heat pipe (9) is provided in the center for cooling the unit. The heat pipe forms at least part of the winding of the transformer.

[0005] The contact surface between the conduit and the core is reduced, so circulation of cooling fluid through the tubes is required to increase cooling, which makes the solution complex and more expensive.

[0006] Patent document US6777835B1 discloses an electric power cooling technology, specifically a device for cooling high-power transformers and electric motors by using thermally conductive material inserted between the turn layers and core laminations of the high-power transformer to provide a low-resistance thermal path to the environment. These strips direct excess heat from the interior to protrusions outside the windings (and core), where forced ventilation or thermally conductive potting compound extracts the heat. The technology provides a significant reduction in weight and volume and a significant increase in power density while operating at a moderately elevated temperature above the ambient. In an embodiment, the transformer is made of materials such as laminated iron, ferrite, and other core materials, and the transformer is formed by insulated copper windings wrapped around the core. Heat is dissipated through the core to the substrate, while thermally conductive strips are placed in preselected locations between the windings and are preferably made of high-modulus graphite laminate to conduct heat along its unidirectional fibers.

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

[0008] Patent document US2015155088A1 discloses a heat dissipation structure for a transformer for dissipating heat generated by a transformer core. The heat dissipation structure includes a heat sink comprising a base plate mounted to the transformer housing and an extension plate extending upward from the base plate. The extension plate includes a center plate and a pair of side plates disposed on opposite sides of the center plate. The side plates are separate from the center plate.

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

[0010] Patent document GB2597670A1 relates to thermal management of an electromagnetic device such as a transformer, comprising a core assembly, a winding 204, a primary heat conducting plate and several secondary heat conducting plates.

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

[0012] The present invention solves the above-referenced and other problems. Summary of the Invention

[0013] The invention relates to an electromagnetic device with improved refrigeration as defined in claim 1.

[0014] The proposed electromagnetic device comprises, in a manner known in the art:

[0015] a magnetic core having at least one conductive coil wound around the core about a central axis, the magnetic core including at least one gap parallel to the central axis to divide the magnetic core into a plurality of independent magnetic core sections, and

[0016] At least one cooling structure comprises a heat sink thermally connected to at least one heat conducting element, each heat conducting element comprises a flat wall made of non-magnetic metal, the flat wall is tightly inserted into one of the gaps of the magnetic core and thermally connected to the magnetic core portion.

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

[0018] Intimate contact between the thermally conductive element and the at least one dissipating surface of the magnetic core allows heat to be transferred from the magnetic core to the thermally conductive element, heat being generated in the magnetic core when the electromagnetic device operates.

[0019] Furthermore, the close contact between the thermally conductive element and the heat sink allows said heat to be transferred from the thermally conductive element to the heat sink where it is dissipated.

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

[0021] The radiator will preferably comprise a dissipative structure in contact with a cooling fluid, such as ambient air, but could also be the cooling liquid of a cooling circuit.

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

[0023] Thermal connection should be understood as physical contact between elements that allows heat transfer by conduction between them, or contact through an interposed heat transfer medium (such as a thermally conductive composition) that allows heat transfer by conduction between the elements.

[0024] For example, between parts of the same single-piece object, between two welded parts, or between two overlapping surfaces with no gap between them, or between two overlapping surfaces with no gap but with a thermally conductive composition between them to fill any imperfections, a thermal connection will exist, thereby increasing the overall thermal conductivity. The thermally conductive composition is preferably a spreadable paste having a relevant thermal conductivity, for example, greater than 5 W / mK, greater than 10 W / mK, or preferably greater than 40 W / mK.

[0025] According to the present invention, the thermally conductive element comprises a flat wall that is tightly inserted into a gap in the magnetic core, the gap dividing the magnetic core into at least two independent magnetic core sections. Preferably, the gap divides the area of ​​the magnetic core surrounded by the conductive coil, such that the at least one thermally conductive element is inserted into the area of ​​the magnetic core surrounded by the conductive coil.

[0026] According to this embodiment, the magnetic core is to be divided into at least two independent core parts facing each other so as to define a gap between them, and it is proposed that the thermally conductive element comprises at least one portion shaped as a flat wall tightly inserted into said gap of the magnetic core, between said at least two independent core parts.

[0027] This structure significantly increases the contact surface between the dissipative magnetic core and the heat-conducting element, thereby increasing the cooling of the electromagnetic device.

[0028] Preferably, the core parts face each other via respective dissipating surfaces and will thus define a gap between said dissipating surfaces. The thermally conductive element will comprise two opposing main surfaces, corresponding to two opposing main surfaces of a flat wall shape, each main surface being in close contact with one of said dissipating surfaces.

[0029] The present invention also proposes the following in an unknown manner:

[0030] The cooling structure is divided into two halves that overlap along a central axis, each half including a heat sink and a portion of a heat-conducting element thermally connected to the corresponding heat sink; and an induced current through the cooling structure is prevented by air gaps or electrical insulators located between multiple portions of the heat-conducting element surrounded by the coil and / or between multiple portions of the cooling structure surrounding the coil.

[0031] According to the above, the cooling structure comprises at least two heat sinks, one heat sink being integrated on each half of the cooling structure, and the at least one heat conducting element being divided into at least two independent parts, each part being thermally connected to one of the heat sinks.

[0032] The two halves of the cooling structure overlap along the central axis so that portions of at least one heat conducting element of one half are separated from portions of the other half by a division transverse to the central axis.

[0033] Preferably, the at least one thermally conductive element is inserted into the region of the magnetic core surrounded by the conductive coil, and the cooling structure may also surround the magnetic device externally. In this case, if the cooling structure is made of a conductive material such as aluminum, an aluminum alloy, undesirable induced currents may be generated through the cooling structure.

[0034] In order to prevent such induced currents, a circular circuit having an area surrounded by the conductive coil should be prevented. In order to prevent these induced currents, the electrical connection between the multiple parts of the at least one thermally conductive element in the area of ​​the magnetic core surrounded by the conductive coil is interrupted by an air gap or an electrical insulator.

[0035] Additionally or alternatively, the circulating circuit can be interrupted to prevent induced current by interrupting the electrical connection between the two halves of the cooling structure through the area not surrounded by the conductive coil. In this case, even if the portion of at least one thermally conductive element surrounded by the conductive coil is in electrical connection, induced current will be prevented.

[0036] According to an embodiment of the invention, the flat walls comprised in said at least one heat conducting element are parallel to a central axis around which said at least one electrically conductive coil is wound.

[0037] The at least one thermally conductive element may include several parallel thermally conductive elements separated by at least two parallel gaps.

[0038] Alternatively, the at least one heat-conducting element may include: one or several parallel heat-conducting elements, which are separated from the magnetic core by at least two parallel gaps; and one or several heat-conducting elements perpendicular to the aforementioned heat-conducting elements, which are further separated from the magnetic core by at least one additional gap perpendicular to the at least two parallel gaps.

[0039] Each heat sink can be, for example, a shell containing the magnetic core or a part of the shell. For example, the outer wall of the shell can dissipate heat into the surrounding air and act as a heat sink.

[0040] The thermally conductive element may further include an external thermally conductive element made of a non-magnetic metal and thermally connected to the heat sink, adjacent to the exterior of the magnetic core, thermally connected to the magnetic core, and / or thermally connected to a flat wall tightly inserted into one of the gaps in the magnetic core. According to this embodiment, the external thermally conductive element will be thermally connected to the exterior of the magnetic core directly or via an interposed heat transfer medium to dissipate heat from the exterior of the magnetic core to the heat sink, and / or will be thermally connected to at least one flat wall tightly inserted into one of the gaps in the magnetic core to help the flat wall dissipate heat from the interior of the magnetic core to the heat sink.

[0041] The heat conducting element and the heat sink can be part of a single body element constituting the cooling structure. This simplifies its manufacture and improves the heat transfer between the heat conducting element and the heat sink.

[0042] Each half of the cooling structure can be made, for example, from cast non-magnetic metal, cast non-magnetic aluminum, or a cast non-magnetic aluminum alloy. Casting each half of the cooling structure allows for custom shapes suitable for increasing heat dissipation and / or reducing the manufacturing cost of the electromagnetic device, thereby making assembly easier and simpler. Preferably, each half of the cooling structure will have a shape that can be produced in a two-part mold.

[0043] Alternatively, each half of the cooling structure can be made of extruded non-magnetic metal, extruded non-magnetic aluminum, or extruded non-magnetic aluminum alloy extruded in a direction perpendicular to the central axis. In this case, the multiple portions of the thermally conductive element of each half of the cooling structure should be a flat wall or several flat walls parallel to each other to allow for manufacturing by extrusion, but the multiple portions of the thermally conductive element of the two halves of the cooling structure can be parallel or perpendicular to each other.

[0044] Manufacturing each half of the cooling structure by an extrusion process significantly increases the speed of manufacturing, reduces its cost, and allows for high dimensional accuracy in the resulting component. 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 with a portion of the cooling structure removed by milling.

[0045] Aluminum and many aluminum alloys are known to be non-magnetic materials and have high thermal conductivity.

[0046] According to the present invention, the heat sink is a housing or a portion of a housing for the electromagnetic device. In this embodiment, the electromagnetic device is housed in a housing, typically a rigid enclosure, to protect it, and the entire enclosure, or a portion thereof, constitutes the heat sink, with the thermally conductive element in close contact with the enclosure or a portion thereof. The walls of the enclosure dissipate the heat, and thus, they constitute part of the cooling structure.

[0047] According to an embodiment of the present invention, the thermally conductive composition surrounds the magnetic core and the at least one coil wound around the magnetic core. The thermally conductive composition is also in close contact with one side of the heat sink to transfer heat from the thermally conductive composition to the heat sink, preferably leaving the opposite side uncovered to dissipate heat. When the heat sink is an enclosure or part of an enclosure for the electromagnetic device, the thermally conductive composition is contained within the enclosure, preferably poured therein.

[0048] Preferably, 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 a natural mineral filler. Optionally, the thermally conductive composition further comprises a second filler comprising aluminum hydroxide.

[0049] According to additional embodiments, the magnetic core may further include a magnetic gap perpendicular to the gap to enhance the magnetic properties of the magnetic core, wherein the magnetic gap completely divides each independent magnetic core portion into two separate sections.

[0050] The magnetic core may comprise a central region, for example having a prismatic or cylindrical shape elongated in a direction parallel to the central axis, around which the at least one coil is wound. The central region of the magnetic core may be divided by gaps.

[0051] Optionally, the magnetic core further comprises a frame region surrounding the central opening, wherein the central region of the magnetic core is contained in the central opening, connected to the frame region at both ends and divides the central opening into two. The frame region of the magnetic core will also be divided by a gap.

[0052] The at least one coil may be wound around a bobbin interposed between the at least one coil and the magnetic core.

[0053] It should be understood that for geometric positions such as parallel, perpendicular, tangential, etc., deviations of up to ±5° from the theoretical position defined by this nomenclature are permitted.

[0054] It should also be understood that any range of values ​​given may not be the best value among the extremes and that adaptation of the present invention to these extremes may be required, such adaptation being within the reach of one skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The foregoing and other advantages and features will be more fully understood from the following detailed description of embodiments, which are illustrative and not restrictive, with reference to the accompanying drawings, in which:

[0056] Figure 1 shows a perspective view of an electromagnetic device according to a first embodiment of the present invention, excluding the cooling structure;

[0057] Figure 2 Shown Figure 1an exploded perspective view of an electromagnetic device as shown, further comprising a cooling structure formed by a lower portion of an enclosure having a planar wall connected thereto and an upper portion of an enclosure having another planar wall connected thereto, and further comprising a thermally conductive composition filling the enclosure;

[0058] Figure 3 shows a perspective view of an electromagnetic device according to a second alternative embodiment of the present invention, wherein the magnetic core is divided by a gap parallel to the central axis and a gap perpendicular to the central axis, the view excluding the cooling structure and the thermally conductive composition;

[0059] Figure 4 Shown Figure 3 An assembled view of the electromagnetic device shown, which also includes a cooling structure and a thermally conductive composition;

[0060] Figure 5 Shown Figure 4 An exploded perspective view of an electromagnetic device is shown showing a cooling structure divided into two halves, each half including a heat sink thermally connected to a portion of a thermally conductive element tightly inserted into a gap in a magnetic core, wherein the heat sinks are located on opposite sides of the electromagnetic device, and further including a thermally conductive composition contained between the two heat sinks;

[0061] Figure 6 Shown according to Figure 5 An exploded perspective view of an electromagnetic device in an alternative embodiment similar to the illustrated embodiment, wherein each half of the cooling structure includes a flat wall, the two flat walls being perpendicular to each other, and the magnetic core includes two slots that are perpendicular to each other;

[0062] Figure 7 Shown according to Figure 5 An exploded perspective view of an electromagnetic device according to an alternative embodiment similar to the illustrated embodiment, wherein each half of the cooling structure includes two planar walls parallel to each other and one planar wall perpendicular to the other planar walls, and the magnetic core includes two parallel slots and one additional slot perpendicular to the other two parallel slots;

[0063] Figure 8 Shown according to Figure 7 An exploded perspective view of an electromagnetic device of an alternative embodiment similar to the embodiment shown, wherein each half of the cooling structure comprises two planar walls perpendicular to each other, the magnetic core comprises two slots perpendicular to each other, and wherein the lower half of the cooling structure comprises two thickened portions of the heat-conducting element, the two thickened portions being in the form of columns parallel to the central axis and attached to the end of one of the planar walls, and wherein the lower half further comprises cooling channels passing through the heat sink and through the columns to produce active cooling of the cooling structure;

[0064] Figure 9 and Figure 10 Shown Figure 8 The vertical section of the heat conducting element shown is coplanar with the central axis. Figure 9 The exploded view and Figure 10 The overall diagram is shown in FIG.

[0065] Figure 11 Shown according to Figure 8 , wherein each half of the cooling structure comprises a flat wall, and wherein the lower half of the cooling structure comprises four thickened portions of a cylindrical heat-conducting element parallel to the central axis at four corner regions around the magnetic core, the columns being thermally connected to the ends of the flat walls by inserted external heat-conducting elements shaped perpendicular to the flat walls inserted into the slots of the magnetic core, and wherein the lower half further comprises cooling channels passing through the heat sink and through the columns, thereby generating active cooling of the cooling structure. DETAILED DESCRIPTION

[0066] The present invention relates to an electromagnetic device, comprising: a magnetic core 10 having 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 .

[0067] The core 10 is formed of several separate core parts 10 ′ facing each other (via respective dissipative surfaces parallel to the central axis X) and defining gaps 11 between them.

[0068] The core 10 may also be separated by gaps 12 perpendicular to the central axis to improve the magnetic properties of the device.

[0069] For example, in Figures 1 to 5 and Figure 11 In the illustrated embodiment, the magnetic core comprises a gap 11 parallel to the central axis X and a gap 12 perpendicular to the central axis, so as to divide the magnetic core 10 into four core parts 10'.

[0070] exist Figure 6 and Figure 8 In the embodiment shown, the core comprises two slits 11 perpendicular to each other and parallel to the central axis X, and a gap 12 perpendicular to the central axis, so as to divide the core 10 into eight core parts 10 ′.

[0071] Finally, in Figure 7 In the embodiment shown, the core comprises two parallel gaps 11 and one gap perpendicular to the other gaps, all of which are parallel to the central axis X; and a gap 12 perpendicular to the central axis, thereby dividing the core 10 into twelve core parts 10'.

[0072] In each case, the cooling structure 30 comprises two halves superposed along the central axis, each half comprising a heat sink 32 thermally connected to a portion of the heat conducting element 31. Preferably, each half of the cooling structure is a single-piece metal element obtained by a casting or extrusion operation or by welding together.

[0073] The portion of the heat conducting element 31 tightly inserted into the gap 11 is formed as a flat wall that is in close contact with the dissipation surface of each independent core portion 10 ′, ie, each major surface of the flat wall is in close contact with one of the dissipation surfaces.

[0074] The non-magnetic thermally conductive elements 31 of the two halves of the cooling structure are interrupted by an air gap or electrical insulator to prevent electrical contact between the two halves of the cooling structure through the portion inserted into the magnetic core 10 and surrounded by the conductive coil 20 .

[0075] according to Figure 2 In the embodiment shown, each half of the heat sink 32 is shaped as a box with an open top to form part of an enclosure for an electromagnetic device, wherein a flat wall stands perpendicular to the base of the enclosure at its center, said flat wall constituting part of a non-magnetic thermally conductive element 31 inserted into the core.

[0076] In this embodiment, the electromagnetic device comprises two symmetrical cooling structures, each defining half of the enclosure, so that when the electromagnetic device is assembled, the enclosure is formed by the combination of the two heat sinks 32 to completely surround the electromagnetic device.

[0077] According to this first embodiment, the capsule is filled with a thermally conductive composition 40 surrounding the core 10 and the coil 20 to enhance the heat transfer from the core 10 towards the heat sink 32 , also through the thermally conductive composition 40 .

[0078] In a second embodiment, each half of the cooling structure comprises a heat sink 32 defining only a base plate or a top plate, which may be part of the enclosure if additional walls are attached to it, or may be only the base plate or the top plate to support all the components of the electromagnetic device and facilitate anchoring them to a support, for example using screws provided in through holes in said base plate and top plate.

[0079] The plate may also comprise side walls parallel to the heat conducting elements on only two sides thereof, the side walls providing a more robust enclosure than a simple base plate and being able to be produced together with the flat walls by an extrusion process.

[0080] According to the second embodiment, the thermally conductive composition 40 is molded and hardened between the heat sinks of the cooling structure 30 .

[0081] Optionally, each half of the cooling structure comprises at least one flat wall and two side walls parallel to the at least one flat wall, the flat wall and side walls of one half being perpendicular to the flat wall and 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 surround the device between the four side walls and the two heat sinks, while each half can be manufactured by extrusion in a cheap and easy way.

[0082] According to a preferred embodiment, the magnetic core comprises a central region, which is elongated in the direction of the central axis X, contained within a central opening of the frame region and connected to said frame region by its ends. An electrically conductive coil 20 is wound around the central region, for example on a bobbin 50 inserted between the coil 20 and the central region of the magnetic core 10.

[0083] The central region may be cylindrical, or prismatic such as a cube.

[0084] In both embodiments, the gap 11 divides the central region and the frame region vertically into two halves, but in the first embodiment, the gap 11 divides the frame region transversely into two C-shaped parts, and in the second embodiment, the gap 11 divides the frame region longitudinally into two thinner frames, each half of the heat-conducting element having an E-shape so as to be inserted not only in the central region of the magnetic core but also between the thinner frames. In this case, each half of the heat-conducting element 31 will have an upper edge remote from the heat sink 32 to which it is connected, which upper edge has an E-shaped profile defining a central protrusion that is inserted into the central region of the magnetic core and two lateral protrusions that are inserted into the frame region of the magnetic core remote from the central region. This embodiment is Figure 4 and Figure 5 Visible in.

[0085] In both embodiments, the gap 12 divides the central area and the frame area into two halves horizontally.

[0086] The non-magnetic heat-conducting element 31 may comprise cooling channels connected to a cooling circuit, preferably comprising a coolant pump.

[0087] The cooling channel may be defined in the heat sink of at least one half of the cooling structure 30 and / or in a portion of the at least one heat conducting element 31. Figure 8 and Figure 11 In the illustrated embodiment, only the lower half of the cooling structure includes a cooling circuit, but both halves may include a similar or symmetrical configuration including cooling channels.

[0088] At least some of the cooling channels may be defined in the flat wall inserted into the slot 11 (when sufficiently thick), or may be defined in an external heat conducting element that is thermally connected to the flat wall that is closely inserted into the slot 11 .

[0089] For example, it is proposed to include cooling channels in a thickened portion of the outer heat-conducting element, which is thicker than the flat wall inserted into the slot 11 of the magnetic core 10 .

[0090] like Figure 8 and Figure 11 As shown in the embodiment of FIG. 1 , the thickened portion, which may be formed as a column, will be directly thermally connected to the edge of the flat wall inserted into the gap of the magnetic core 10, as shown in FIG. Figure 8 Alternatively, the thermal connection can be made by forming the inserted external heat-conducting element into a flat wall perpendicular to the flat wall inserted into the gap 11, as shown in FIG. Figure 11 shown.

[0091] The cooling channel may include a plurality of parallel holes 61 and at least one transverse hole 62 that intersects and interconnects those plurality of parallel holes 61. Figure 9 and Figure 10 shown.

[0092] 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 heat-conducting element 31 of at least one half of the cooling structure 30. Each blind hole will comprise an inner wall 63 that is tightly inserted into the blind hole and connected, for example by screwing, to a cover attached to the open end of each blind hole, the inner wall 63 dividing the blind hole longitudinally into two channels and defining a connection between these two channels at the bottom of the blind hole, thereby generating a cooling effect along the entire length of the blind hole.

[0093] Typically, the inner wall 63 is shorter than the blind hole into which it is inserted, or has a transverse opening at its distal end, thereby creating the two parallel channels in each blind hole, one channel connected to one section of the transverse hole and the other channel connected to the other section of the transverse hole, to push the cooling fluid to the bottom of each blind hole.

[0094] according to Figure 9 and Figure 10 In the embodiment shown, the blind holes extend through the heat sink 32 and have open ends on the side of the heat sink 32 opposite the side of the heat sink connected to the thermally conductive element 31. These parallel holes 61 are aligned and intersect with a transverse hole 62 in the area adjacent to their open ends. In this embodiment, the transverse hole is coplanar with and perpendicular to the parallel holes 61 and completely traverses the heat sink 32 to which it is attached.

Claims

1. An electromagnetic device with improved refrigeration, comprising: A magnetic core (10) having at least one conductive coil (20) wound around the core around a central axis (X), the magnetic core (10) comprising at least one gap (11) parallel to the central axis (X) for dividing the magnetic core (10) into a plurality of independent magnetic core parts (10'), and at least one cooling structure (30), each comprising a heat sink (32) thermally connected to at least one heat-conducting element (31), each heat-conducting element (31) comprising a flat wall made of non-magnetic metal, the flat wall being tightly inserted into one of the gaps (11) of the magnetic core (10) and being thermally connected to the magnetic core portion (10'); It is characterized by: The cooling structure (30) is divided into two halves overlapping along the central axis (X), each half comprising a heat sink (32) and a portion of the heat conducting element (31) thermally connected to the corresponding heat sink (32), and Induction currents through the cooling structure (30) are prevented by air gaps or electrical insulators between portions of the thermally conductive element (31) surrounded by the coil (20) and / or between portions of the cooling structure (30) surrounding the coil (20).

2. The electromagnetic device according to claim 1, wherein The at least one heat-conducting element (31) is a plurality of parallel and / or vertical heat-conducting elements (31).

3. The electromagnetic device according to claim 1 or 2, wherein: Each heat sink (32) is a casing containing the magnetic core (10) or a part of the casing.

4. The electromagnetic device according to claim 1, 2 or 3, wherein: The heat-conducting element (31) further comprises an external heat-conducting element made of non-magnetic metal and thermally connected to the heat sink (32), adjacent to the exterior of the magnetic core (10), thermally connected to the magnetic core (10) and / or thermally connected to the flat wall tightly inserted into one of the gaps of the magnetic core.

5. Electromagnetic device according to any one of the preceding claims, wherein Each half of the cooling structure (30) is a single-piece element made of cast metal, cast aluminum or cast aluminum alloy, or a single-piece element made of extruded metal, extruded aluminum or extruded aluminum alloy extruded in a direction perpendicular to the central axis (X).

6. The electromagnetic device according to any one of the preceding claims 1 to 4, wherein: 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 being perpendicular to the flat wall of the other half.

7. The electromagnetic device according to claim 6, wherein Each half of the cooling structure further comprises two side walls, which are parallel to the flat wall and adjacent to the outer side of the magnetic core (10).

8. Electromagnetic device according to any one of the preceding claims, wherein The magnetic core (10) and the at least one electrically conductive coil (20) are embedded in a thermally conductive composition (40) that is in thermal contact with each heat sink (32).

9. The electromagnetic device according to claim 8, wherein The thermally conductive 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; or A mixture of silicone resin and at least a first filler, or a mixture of silicone resin and a first filler comprising a natural mineral filler and a second filler comprising aluminum hydroxide.

10. Electromagnetic device according to any one of the preceding claims, wherein The magnetic core further comprises a magnetic gap (12) perpendicular to the central axis (X) for enhancing the magnetic properties of the magnetic core (10), wherein the magnetic gap (12) completely divides each independent magnetic core part (10') into two separate sections.

11. Electromagnetic device according to any one of the preceding claims, wherein At least one of the coils (20) is wound around a bobbin (50) interposed between the at least one coil (20) and the magnetic core (10).

12. Electromagnetic device according to any one of the preceding claims, wherein The cooling structure (30) also includes a cooling channel connected to a cooling circuit.

13. The electromagnetic device according to claim 12, wherein The cooling channel is defined in the heat sink of at least one half of the cooling structure (30) and / or in a portion of the at least one heat conducting element (31).

14. The electromagnetic device according to claim 12 or 13, wherein: The cooling channel includes a plurality of parallel holes (61) and at least one transverse hole (62), wherein the transverse hole intersects with the plurality of parallel holes (61) and interconnects the plurality of parallel holes.

15. The electromagnetic device according to claim 14, wherein At least some of the parallel holes (61) are blind holes, which are defined in a portion of the at least one heat-conducting element (31) of at least one half of the cooling structure (30) and include an inner wall (63) that is tightly inserted into the blind hole, the inner wall (63) longitudinally dividing the blind hole into two channels and defining a connection between the two channels at the bottom of the blind hole.

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