Electromagnetic device with improved cooling

Abstract

Enhanced cooling electromagnetic device comprising a magnetic core (10) with at least one electroconductive winding (20) and at least one slot (11) dividing the magnetic core (10) into several independent magnetic core portions (10'), and at least one cooling structure (30) comprising a heat sink (32) in thermal connection with at least one thermally conductive element (31) comprising a flat wall made of a non-magnetic metal tightly inserted into one of the slots (11) of the magnetic core (10); wherein the cooling structure (30) further comprises cooling channels connected to a cooling circuit, the cooling channels being defined in the heat sink and / or in the portion of at least one thermally conductive element (31) of the cooling structure (30);and the cooling channels comprising several parallel holes (61) and at least one transverse hole (62) intercepting these several parallel holes (61) and connecting them together.;

Description

Title of the invention: Electromagnetic device with improved cooling. Technical field

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

[0002] The electromagnetic device comprises a magnetic core around which an electroconductive winding is wound. Improved cooling is achieved by means of at least one cooling structure comprising a thermally conductive element, made of a non-magnetic material, in intimate contact with a heat sink, the thermally conductive element having a flat wall inserted by a tight fit into a slot in the magnetic core which divides the magnetic core into two independent portions of the magnetic core. BACKGROUND OF THE INVENTION

[0003] In order to dissipate the heat (produced by the generated eddy currents) from the core of the magnetic power unit, particularly in the case of power transformers, several approaches have been considered. Examples include increasing the wire gauge to reduce resistive losses; immersing the transformer in circulating cooling oil; air-cooling the transformer windings; increasing the transformer operating frequency to reduce the windings; and increasing the thermal conductivity of the insulating compound surrounding the transformer windings. However, these solutions negatively impact the size and weight of the transformer designs, limiting their use. Without proper cooling, the efficiency and reliability of these transformers and inductors are significantly reduced.

[0004] Document DE19814896 discloses a high-current power transformer having a closed cylindrical core made of a soft magnetic material with high permeability, high saturation induction, and low magnetic losses. This core is surrounded by a primary winding and a secondary winding. The core is contained within a casing which is then filled with a suitable resin. At least one heat tube (9) for cooling the transformer group is located in the middle. The heat tube forms at least part of the transformer winding.

[0005] Since the contact area between the conduit and the magnetic core is reduced, it is therefore necessary to circulate a refrigerant fluid in the tube in order to increase cooling, making this solution more complex and increasing its cost.

[0006] US patent 6777835B1 discloses an electrically powered cooling technique, and in particular a cooling device for a high-power electrical transformer and electric motors by means of a thermally conductive material sandwiched between the winding layers of a high-power transformer and laminated iron core materials, so as to provide a thermal path with low environmental resistance. The lamellae conduct excess heat from the interior to protrusions outside the windings (and the core), the heat then being extracted either by forced air or by the thermally conductive encapsulating compound. This technique offers a considerable reduction in weight and size, as well as a substantial increase in power density, while being conducted at a temperature only slightly above ambient temperature.In one embodiment, a transformer is made of a material such as rolled iron, ferrite, and other core materials, and the transformer consists of insulated copper windings wound around the core. Heat is dissipated through the core to a base plate, while thermally conductive lamellae are arranged in predetermined positions between the windings and are preferably made of high-modulus lamellar graphite material, so as to carry heat along the orientation of its fiber, which is unidirectional.

[0007] US patent 2004257187 A1 discloses an electromagnetic device comprising a first tubular magnetic core segment; a second tubular magnetic core segment spaced 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 in the first tubular magnetic core segment and a second portion of the primary conductive winding is disposed in the second tubular magnetic core segment. The magnetic device further comprises a heat extraction means with conductive elements, such as cooling fins, in communication with at least a portion of the outer surface of the first tubular magnetic core segment and at least a portion of the outer surface of the second tubular magnetic core segment.

[0008] US2015155088A1 discloses a heat dissipation structure for a transformer designed to dissipate heat generated from a transformer core, comprising a heat dissipation plate having a lower plate assembled in a transformer housing and an extension plate extending upward from the lower plate. The extension plate has a central plate and a pair of side plates, each arranged on one opposite side of the central plate. The pair of side plates are separated from the central plate.

[0009] Document CN113257545A relates to a high-power, high-efficiency, high-frequency transformer comprising an aluminum plate heat sink having a first aluminum plate, a second aluminum plate and a third aluminum plate arranged one behind the other.

[0010] Document GB2597670A1 relates to the thermal management of an electromagnetic device such as a transformer, comprising a core assembly, windings 204, a primary thermally conductive plate and several secondary thermally conductive 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 present invention solves the aforementioned problems and others. DESCRIPTION OF THE INVENTION

[0013] The present invention relates to an improved cooling electromagnetic device, as defined in claim 1.

[0014] The proposed electromagnetic device comprises, in a manner known per se from the prior art: a magnetic core around which is wound, around a central axis, at least one electroconductive winding, the magnetic core having at least one slot, parallel to the central axis and dividing the magnetic core into several independent portions of magnetic core, and at least one cooling structure, each comprising a heat sink in thermal bond with at least one thermally conductive element, each thermally conductive element comprising a flat wall, made of a non-magnetic metal, inserted by tight fit into one of the slots of the magnetic core in thermal bond with the portions of the magnetic core.

[0015] The thermally conductive element is an element made of a non-magnetic material, which does not interfere with the magnetic fields generated at the electromagnetic device during its operation, and which has a high conductivity, for example, greater than 120 W / mK, greater than 160 W / mK, or preferably greater than 210 W / mK. Typically, the thermally conductive element will be made of a non-magnetic metal such as aluminum or an aluminum alloy.

[0016] The intimate contact between the thermally conductive element and at least one dissipation surface of the magnetic core allows heat transfer from the magnetic core, where it is generated when the electromagnetic device is in operation, up to the thermally conductive element.

[0017] Furthermore, the intimate 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, from which the heat is dissipated.

[0018] The heat sink will also be made of a material with 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.

[0019] Preferably, the heat sink will have a dissipation arrangement in contact with a refrigerant fluid, for example, the surrounding air, but it can also be a refrigerant liquid from a cooling circuit.

[0020] The dissipation arrangement may include, for example, a surface provided with notches, ribs, rods or any other surface enlargement arrangement intended to increase the surface area of ​​the heat sink exposed to the refrigerant.

[0021] Thermal bonding means a physical contact of the elements which allows heat transfer between them by conduction, or a contact through an interposed heat transfer means, such as a heat-conducting composition, allowing heat transfer between them by conduction through said heat transfer means.

[0022] There will be a thermal bond, for example, between parts of the same object in a single piece, between two welded components, or between two superimposed surfaces without gaps between them, or between two superimposed surfaces without gaps between them but having an interposed heat-conducting composition so as to fill any irregularity, thus increasing the overall thermal conductivity. The heat-conducting composition is preferably a paste suitable for coating and having a high thermal conductivity, for example, greater than 5 W / mK, greater than 10 W / mK, or preferably greater than 40 W / mK.

[0023] According to the present invention, the thermally conductive element comprises a flat wall inserted by a tight fit into a slot in the magnetic core, said slot dividing the magnetic core into at least two independent magnetic core portions. Preferably, said slot divides the region of the magnetic core surrounded by the electroconductive winding, such that at least one thermally conductive element is inserted into said region of the magnetic core surrounded by the electroconductive winding.

[0024] In accordance with the foregoing, the magnetic core shall be divided into at least two independent magnetic core portions oriented with respect to each other, defining a slot between them, and it is proposed that the conducting element thermal comprises at least one portion configured as a flat wall inserted by tight fit into said slot of the magnetic core, between the at least two independent portions of magnetic core.

[0025] This construction remarkably increases the contact surfaces between the dissipative magnetic core and the thermally conductive element, thereby increasing the cooling of the electromagnetic device.

[0026] Preferably, the portions of the magnetic core are oriented relative to each other by means of corresponding dissipation surfaces, and consequently, the slot will be formed between said dissipation surfaces. The thermally conductive element will comprise two opposing principal surfaces, corresponding to the two opposing principal surfaces of the flat-wall conformation, each of them being in intimate contact with one of said dissipation surfaces.

[0027] The present invention also proposes, in a manner not known, the following: the cooling structure also comprises cooling channels connected to a cooling circuit, the cooling channels being provided on the heat sink and / or on the portion of at least one thermally conductive element of the cooling structure; and The cooling channels include several parallel holes and at least one transverse hole intersecting said several parallel holes so as to connect them together.

[0028] The cooling channels can be connected to a cooling circuit, preferably comprising a refrigerant liquid pump.

[0029] At least some of the parallel holes may be blind holes formed on at least one thermally conductive element of the cooling structure. These blind holes may have an internal wall inserted into them by an interference fit, the internal wall longitudinally dividing the blind hole into two channels and defining a connection between these two channels in a lower portion of the blind hole.

[0030] Some at least of the cooling channels may be provided on the flat wall inserted in the slot, when the latter is sufficiently thick, or may be provided on portions of the thermally conductive elements external to the slot, which constitute external thermally conductive elements, being in thermal connection with the flat wall inserted by tight fit in the slot.

[0031] It is proposed, for example, to provide cooling channels on bulging portions of the external thermally conductive elements, thicker than the flat wall inserted in the slot of the magnetic core.

[0032] Said bulging portions, which can be configured in the form of a pillar, will be thermally connected to the edges of the flat walls inserted into the slot of the magnetic core either directly, or via the interposed external thermally conductive element, also configured as flat walls perpendicular to the flat wall inserted in the slot.

[0033] Optionally, the cooling structure can be divided into two superimposed halves along the central axis, each half comprising a heat sink and a portion of the thermally conductive elements thermally connected to the corresponding heat sink. In this embodiment, the passage of induced currents through the cooling structure will be prevented by means of an air gap, or an electrical insulator, located between the portions of the thermally conductive elements surrounded by the electroconductive winding and / or between the portions of the cooling structure surrounding the electroconductive winding.

[0034] In accordance with the above, the cooling structure comprises at least two heat sinks, each being integrated into each half of the cooling structure, and at least one thermally conductive element is divided into at least two independent portions, each portion being thermally connected to one of the heat sinks.

[0035] The two half-parts of the cooling structure are superimposed in the direction of the central axis, so that the portions of at least one thermally conductive element of one half-part are separated from the portions of the other half-part by a separation transverse to the direction of the central axis.

[0036] Preferably, at least one thermally conductive element is inserted in the region of the magnetic core surrounded by the electroconductive winding, and the cooling structure may also externally surround the magnetic device. In this case, undesirable induction currents may be generated through the cooling structure if it is made of an electrically conductive material, such as aluminum or an aluminum alloy.

[0037] To prevent these induction currents, a circular electrical circuit with a region surrounded by the electroconductive winding should be avoided. To prevent these induction currents, an interruption of the electrical connection between portions of the magnetic core is provided, at least one thermally conductive element, by means of an air gap or a piece of electrical insulation, in the region of the magnetic core surrounded by the electroconductive winding.

[0038] In addition or as an alternative, the interruption of the circular circuit, to prevent induction currents, can be achieved by interrupting the electrical connection between the two halves of the cooling structure at the level of the region of the cooling structure not surrounded by the electroconductive winding. In this case, induction currents will be prohibited even if the portions of at least one The thermally conductive element surrounded by the electroconductive winding is electrically connected.

[0039] According to one embodiment of the invention, the flat wall provided on at least one thermally conductive element is parallel to the central axis around which at least one electroconductive winding is wound.

[0040] The at least one thermally conductive element may comprise several parallel thermally conductive elements, dividing the magnetic core at the level of at least two parallel slots.

[0041] Alternatively, the at least one thermally conductive element may comprise one or more parallel thermally conductive elements, dividing the magnetic core at the level of at least two parallel slots, and one or more thermally conductive elements perpendicular to the aforementioned thermally conductive elements, further dividing the magnetic core at the level of at least one additional slot perpendicular to the aforementioned at least two parallel slots.

[0042] Each heat sink can be, for example, a housing containing the magnetic core, or a portion thereof. The external walls of the housing can, for example, dissipate heat into the surrounding air, which acts as a heat sink.

[0043] The thermally conductive elements may further comprise external thermally conductive elements, made of a non-magnetic metal and thermally connected to the heat sink, in a position adjacent to the outside of the magnetic core, thermally connected to the magnetic core and / or thermally connected to the flat wall inserted by a tight fit into one of the slots of the magnetic core. According to this embodiment, the external thermally conductive element will be thermally connected to the outside of the magnetic core, either directly or via an interposed heat transfer means, which dissipates heat from the outside of the magnetic core to the heat sink, and / or will be thermally connected to at least one flat wall inserted by a tight fit into a slot of the magnetic core, so as to assist the flat wall in dissipating heat from the inside of the magnetic core to the heat sink.

[0044] The thermal conductive element and the heat sink can be part of a single, monolithic element constituting the cooling structure. This simplifies its construction and improves heat transfer between the thermal conductive element and the heat sink.

[0045] Each half-part of the cooling structure can, for example, be made of non-magnetic cast metal, non-magnetic cast aluminum, or non-magnetic cast aluminum alloy. Casting each half-part of the cooling structure allows for the creation of customized configurations. capable of increasing heat dissipation and / or reducing the manufacturing costs of the electromagnetic device, while also making its assembly easier and simpler. Preferably, each half of the cooling structure will have a shape suitable for manufacturing in a two-part mold.

[0046] Alternatively, each half of the cooling structure can be made of a non-magnetic extruded metal, a non-magnetic extruded aluminum, or a non-magnetic extruded aluminum alloy that is extruded perpendicular to the central axis. In this case, the portions of the thermally conductive element of each half of the cooling structure will be a flat wall or several parallel flat walls, so as to allow their fabrication by extrusion, but the portions of the thermally conductive element of the two half-parts of the cooling structure can be parallel or perpendicular to each other.

[0047] Manufacturing each half of the cooling structure by an extrusion process significantly increases the production rate, while reducing its cost, and allows for high dimensional accuracy of the parts obtained. 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, including certain portions thereof removed by milling.

[0048] It is well known that aluminium and many aluminium alloys are non-magnetic materials and possess high thermal conductivity.

[0049] According to the present invention, the heat sink is a housing, or a portion of a housing, for the electromagnetic device. As described above, the electromagnetic device will be housed in a housing, typically a rigid housing designed to protect it, and the heat sink will consist of the entire housing or a portion thereof, the thermally conductive element being in close contact with said housing or a portion thereof. Since the walls of the housing ensure heat dissipation, said walls are therefore part of the cooling structure.

[0050] According to one embodiment of the invention, a thermally conductive composition surrounds the magnetic core and at least one electroconductive winding wound around the magnetic core. The thermally conductive composition will also be in intimate contact with one side of the heat sink, so as to transfer heat from the thermally conductive composition to the heat sink, the opposite side of which will preferably remain uncovered to dissipate the heat. When the heat sink is a housing or a portion of a housing of the electromagnetic device, the thermally conductive composition will be contained within said housing, preferably cast into it.

[0051] Preferably, the thermally conductive composition comprises a mixture of a silicone resin and at least one first filler, or of a silicone resin and a first filler including a natural mineral filler. Optionally, the thermally conductive composition further comprises a second filler including aluminum hydroxide.

[0052] According to an additional embodiment, the magnetic core may further comprise a magnetic gap, perpendicular to the slot, intended to increase the magnetic performance of the magnetic core, said gap entirely dividing each of the independent portions of the magnetic core into two independent sections.

[0053] The magnetic core may comprise, for example, a central region of prismatic or cylindrical shape elongated in a direction parallel to the central axis, with at least one electroconductive winding wound around said central region. Said central region of the magnetic core shall be divided by the slot.

[0054] Optionally, the magnetic core further comprises an armature region surrounding a central opening, the central region of the magnetic core being arranged within said central opening, connected to the armature region at both ends and dividing the central opening in two. Said armature region of the magnetic core will also be divided by the slot.

[0055] At least one electroconductive winding can be wound around a coil interposed between the at least one electroconductive winding and the magnetic core.

[0056] It will be understood that references to geometric position, such as parallel, perpendicular, tangent, etc., allow deviations of up to plus or minus 5° from the theoretical position defined by these terms.

[0057] It will also be understood that over any given range of values, it is possible that the limit values ​​may not be optimal, and adaptations of the invention may be required in order for these limit values ​​to be applicable, such adaptations being within the reach of a person skilled in the art. BRIEF DESCRIPTION OF THE FIGURES

[0058] The above and other advantages and features will be better understood from the following detailed description of an embodiment with reference to the accompanying drawings, which are to be taken by way of illustration and not limitation, in which:

[0059] Figure 1 shows an exploded perspective view of the electromagnetic device according to an embodiment in which the cooling structure comprises a heat sink and a thermally conductive element having two flat walls perpendicular to each other and inserted into two perpendicular slots in the magnetic core, as well as two bulges in the form of parallel pillars. to the central axis, attached to the ends of one of the flat walls, the cooling structure includes cooling channels passing through the heat sink and through said pillars, so as to generate active cooling of the cooling structure.

[0060] Fig. 2 shows a perspective view of the electromagnetic device shown in Fig. 1, in which the magnetic core is divided by a slit, parallel to the central axis, and a gap perpendicular to said central axis, the cooling structure and the conductive composition not being visible in this figure.

[0061] [Fig.3] shows an exploded perspective view of the electromagnetic device according to an alternative embodiment similar to that shown in [Fig.1], in which the cooling structure comprises two half-parts, the lower half-part being equal to that described in [Fig.1], and the upper half-part having an additional heat sink and two flat walls perpendicular to each other, the upper half-part being devoid of cooling channels.

[0062] Figures 4 and 5 show a vertical cross-section of the thermally conductive element shown in [Fig.3] coplanar with the central axis, representing the exploded view in [Fig.4] and the assembled view in [Fig.5].

[0063] Fig. 6 shows an exploded perspective view of the electromagnetic device according to an alternative embodiment similar to that shown in Fig.3], wherein each half of the cooling structure has a flat wall, and wherein the lower half of the cooling structure has, at the four corner regions surrounding the magnetic core, four bulges of the thermally conductive element in the form of pillars parallel to the central axis, said pillars being thermally connected to the ends of said flat wall by an interposed external thermally conductive element configured as a flat wall perpendicular to the flat wall inserted in the slot of the magnetic core, and wherein this lower half further has cooling channels passing through the heat sink and through said pillars, so as to generate active cooling of the cooling structure.

[0064] Detailed description of the invention and particular embodiments

[0065] The present invention relates to an electromagnetic device comprising a magnetic core (10), having an electroconductive winding (20) wound around a central axis (X) surrounding the magnetic core (10) or a part thereof, and a cooling structure (30) in intimate contact with the magnetic core (10).

[0066] The magnetic core (10) is composed of several independent magnetic core portions (10'), oriented relative to each other by means of surfaces of corresponding dissipation parallel to the central axis (X), so as to provide between them a slit (11).

[0067] The magnetic core (10) can also be divided by a gap (12) perpendicular to the central axis, in order to improve the magnetic performance of the device.

[0068] For example, in the embodiment shown in [Fig.3], the magnetic core has two slots (11) parallel to the central axis (X) and perpendicular to each other, and a gap (12) perpendicular to the central axis, dividing the magnetic core (10) into eight portions of magnetic core (10').

[0069] The non-magnetic, thermally conductive element (31) may include cooling channels connected to a cooling circuit, which preferably includes a coolant pump. Optionally, the cooling channels may also be provided at the heat sink.

[0070] Some at least of the cooling channels may be provided on the flat wall inserted in the slot (11), when the latter is sufficiently thick, or may be provided on external thermally conductive elements in thermal connection with the flat wall inserted by tight fit in the slot (11).

[0071] It is proposed, for example, to provide cooling channels on bulging portions of the external thermally conductive elements, thicker than the flat wall inserted in the slot (11) of the magnetic core (10).

[0072] Said bulging portions, which can be configured in the form of a pillar, will be thermally connected to the edges of the flat walls inserted in the slot of the magnetic core (10) either directly or via the interposed external thermally conductive element, also configured in the form of flat walls perpendicular to the flat wall inserted in the slot (11).

[0073] The cooling channels may include several parallel holes (61) and at least one transverse hole (62) intersecting said several parallel holes (61) so as to connect them together.

[0074] Preferably, at least some of the parallel holes (61) are blind holes, typically parallel to the central axis (X), formed on the portion of at least one thermally conductive element (31) of at least one of the half-parts of the cooling structure (30). Each blind hole shall have an internal wall (63) inserted by press fit into it and connected to a cover attached to the open end of each blind hole, for example by threading, so that the internal wall (63) longitudinally divides the blind hole into two channels and defines a connection between these two channels in a lower part of the blind hole, thus generating a cooling effect over the entire length of the blind hole.

[0075] Typically, the inner wall (63) is shorter than the blind bore into which it is inserted, or it has at its distal end a transverse opening, so as to create on each blind bore said two parallel channels, one being connected to one segment of the transverse bore and the other being connected to the other segment of the transverse bore, so as to push the refrigerant fluid towards the lower part of each blind bore.

[0076] According to one embodiment, blind holes pass through the heat sink (32), having an open end on one 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 intersected, at a region adjacent to their open ends, by a transverse hole (62) which, in this embodiment, is coplanar and perpendicular to the parallel holes (61), said transverse hole passing completely through the heat sink (32) connected to it.

[0077] The cooling structure (30) may comprise two superimposed half-parts in the direction of the central axis, each half-part having a heat sink (32) thermally connected to a portion of the thermally conductive element (31). Preferably, each half-part of the cooling structure is a one-piece metallic element produced by casting or extrusion or assembled by welding.

[0078] One or both halves of the cooling structure may include cooling channels. For example, even though in the embodiments shown in Figures 3 and 6 the cooling circuit is present only on the lower half of the cooling structure, the two halves may have similar or symmetrical configurations including cooling channels.

[0079] The portion of the thermally conductive element (31) inserted by tight fit into the slot (11) is configured as a flat wall, being in intimate contact with the dissipation surfaces of each of the independent magnetic core portions (10'), that is to say, with each main surface of the flat wall which is in intimate contact with one of the dissipation surfaces.

[0080] The non-magnetic thermally conductive element (31) of the two half-parts of the cooling structure is interrupted by an air gap, or by an electrical insulator, so as to avoid electrical contact between the two half-parts of the cooling structure through the portion inserted in the magnetic core (10) and surrounded by the electroconductive winding (20).

[0081] According to the embodiment shown in [Fig. 2], each half of the heat sink (32) is configured as a partially open housing upper, forming a portion of a housing intended for the electromagnetic device, in the center of which stands the flat wall, perpendicular to the base of said housing, said flat wall constituting a portion of the thermally conductive non-magnetic element (31) inserted in the core.

[0082] In this embodiment, the electromagnetic device comprises two symmetrical cooling structures, each defining a half-part of the housing, so that, when the electromagnetic device is assembled, the combination of the two heat sinks (32) forms a housing that completely encloses the electromagnetic device.

[0083] According to this first embodiment, said housing is filled with a thermally conductive composition (40) in which the magnetic core (10) and the electroconductive winding (20) are embedded, so as to further increase the thermal transmission of heat through also said thermally conductive composition (40) from the magnetic core (10) to the heat sink (32).

[0084] In the second embodiment, each half of the cooling structure includes a heat sink (32) defining only a base plate or a top plate, which may be part of a housing after assembly of additional walls, or it may be a simple base plate or top plate intended to support all the components of the electromagnetic device and to facilitate the fixing of the latter on a support, for example, by means of screws inserted into through holes provided on said base plate and top plate.

[0085] Said plate may also include, only on two sides thereof, side walls parallel to the thermally conductive element, the side walls providing a more secure housing than the base plate alone and being able to be made of material with the flat wall by an extrusion process.

[0086] According to the second embodiment, the thermally conductive composition (40) is poured and then allowed to harden between the heat sinks of the cooling structure (30).

[0087] Optionally, each half-part of the cooling structure comprises at least one flat wall and two side walls parallel to said at least one flat wall, the flat wall and side walls of one half-part being perpendicular to the flat wall and side walls of the other half-part, so that the device is entirely enclosed by the two side walls of one half-part and the two other side walls of the other half-part by being framed by four side walls and two heat sinks, while each half-part is produced economically and easily by extrusion.

[0088] According to a preferred embodiment, the magnetic core has a central region, elongated in the direction of the central axis (X), housed in a central opening of an armature region and connected at its ends to said armature region. The electroconductive winding (20) is wound around the central region, for example, on a coil 50 interposed between the electroconductive winding (20) and the central region of the magnetic core (10).

[0089] The central region may have a cylindrical or prismatic shape such as a cube-like shape.

[0090] Although in both embodiments the slot (11) vertically divides the central region and the armature region in two, in the first embodiment the slot (11) transversely divides the armature region into two C-shaped portions, and in the second embodiment the slot (11) longitudinally divides the armature region into two thinner armatures, each half-portion of the thermally conductive element having an E-shape for insertion not only into the central region of the magnetic core, but also between the thinner armatures. In this case, each half-portion of the thermally conductive element (31) will have an upper edge, away from the heat sink (32) connected to it, having an E-shaped profile defining a central protrusion inserted into the central region of the magnetic core, and two lateral protrusions inserted into the armature region of the magnetic core at a distance from the central region.This embodiment can be seen in Figures 4 and 5.

[0091] In both embodiments, the gap (12) horizontally divides the central region and the reinforcement region into two.

Claims

Demands

1. Improved cooling electromagnetic device comprising: a magnetic core (10) around which is wound, around a central axis (X), at least one electroconductive winding (20), the magnetic core (10) having at least one slot (11), parallel to the central axis (X) and dividing the magnetic core (10) into several independent magnetic core portions (10'), and at least one cooling structure (30) each comprising a heat sink (32) in thermal connection with at least one thermally conductive element (31), each thermally conductive element (31) comprising a flat wall, made of a non-magnetic metal, inserted by press fit into one of the slots (11) of the magnetic core (10) in thermal connection with the magnetic core portions (10');characterized in that the cooling structure (30) also comprises cooling channels connected to a cooling circuit, the cooling channels being provided on the heat sink and / or on a portion of at least one thermally conductive element (31) of the cooling structure (30); and the cooling channels comprising several parallel holes (61) and at least one transverse hole (62) intersecting said several parallel holes (61) so as to connect them together.

2. Electromagnetic device according to claim 1, wherein at least some of the parallel holes (61) are blind holes formed on at least one thermally conductive element (31) of the cooling structure (30) and have an inner wall (63) inserted by tight fit into them, the inner wall (63) longitudinally dividing the blind hole into two channels and defining a connection between these two channels in a lower part of the blind hole.

3. Electromagnetic device according to claim 1 or 2, wherein at least one thermally conductive element (31) is several parallel and / or perpendicular thermally conductive elements (31).

4. Electromagnetic device according to claim 2 or 3, wherein at least some of the cooling channels are provided on the flat wall inserted by tight fit into the slot (11), or are provided on portions of the thermally conductive elements external to the slot (11), which constitute external thermally conductive elements, being in thermal connection with the flat wall inserted by tight fit into the slot (11).

5. Electromagnetic device according to any one of the preceding claims, wherein each heat sink (32) is a housing accommodating at least part of the magnetic core (10), or a portion of said housing.

6. Electromagnetic device according to any one of the preceding claims, wherein the thermally conductive elements (31) further comprise at least one external thermally conductive element adjacent to, and thermally connected with, the exterior of the magnetic core (10), the external thermally conductive element being made of a non-magnetic metal and being thermally connected with the heat sink (32), and / or with the flat wall inserted by a tight fit into one of the slots of the magnetic core.

7. Electromagnetic device according to any one of the preceding claims, wherein the heat sink (32) and the thermally connected thermally conductive element (31) thereto constitute a one-piece element made of cast metal, cast aluminum or cast aluminum alloy, or a one-piece element made of extruded metal, extruded aluminum or extruded aluminum alloy which is extruded in a direction perpendicular to the central axis (X).

8. An electromagnetic device according to any one of the preceding claims, wherein the cooling structure (30) is divided into two superimposed half-parts in the direction of the central axis (X), each half-part comprising a heat sink (32) and a portion of the thermally conductive elements (31) thermally connected to the corresponding heat sink (32), and the passage of induction currents through the cooling structure (30) is prevented by means of an air gap, or electrical insulator, located between the portions of the thermally conductive elements (31) surrounded by the winding. electroconductive (20) and / or between portions of the cooling structure (30) surrounding the electroconductive winding (20).

9. Electromagnetic device according to claim 8, wherein each half-part of the cooling structure (30) is a one-piece element made of extruded metal, extruded aluminum or extruded aluminum alloy which is extruded in a direction perpendicular to the central axis (X), the flat wall of one half-part being perpendicular to the flat wall of the other half-part.

10. Electromagnetic device according to claim 9, wherein each half-part of the cooling structure further comprises two side walls, parallel to the flat wall, adjacent to an outer side of the magnetic core (10).

11. Electromagnetic device according to any one of the preceding claims, wherein the magnetic core (10) and at least one electroconductive winding (20) are embedded in a thermally conductive composition (40), the thermally conductive composition (40) being in thermal contact with each heat sink (32).

12. Electromagnetic device according to claim 11, wherein the thermally conductive composition comprises: a mixture of a silicone resin and at least one first filler or of a silicone resin and a first filler including a natural mineral filler; or a mixture of a silicone resin and at least one first filler or of a silicone resin and a first filler including a natural mineral filler and a second filler including aluminum hydroxide.

13. 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), intended to increase the magnetic performance of the magnetic core (10), said gap (12) entirely dividing each of the independent portions of the magnetic core (10') into two independent sections.

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

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