Electronic component, specifically three-phase transformer for isolated voltage converter

Abstract

Electronic component (15), comprising: - a housing (50) having a body (51) and a cover (52), the cover being adapted to come into contact with an electronic card (53), - a magnetic circuit (22), - two electrical conductors (31, 32) each having a portion disposed around the same part (27) of the magnetic circuit, each of said portions forming between a first and a second end a winding, these two windings being inductively coupled to each other via the magnetic circuit, - a support (30) for the two electrical windings, disposed between said electrical conductors (31, 32) and said part (27) of the magnetic circuit, the support extending along an axis, and - a cooling circuit (61) externally bathing at least the area of ​​the body (55) axially furthest from the cover (52),characterized by the fact that it comprises at least one extension (70) connected to the cover (52) and extending axially along all or part of the magnetic circuit (22) in the direction of said area (55) of the body. Abbreviated figure: Fig. 3,

Description

Title of the invention: Electronic component, in particular three-phase transformer for isolated voltage converter

[0001] The present invention relates to an electronic component comprising a magnetic circuit, and at least two electrical conductors each having a portion arranged around the same part of the magnetic circuit, each of said portions forming between a first and a second end a winding, these two windings being in inductively coupled with each other via the magnetic circuit.

[0002] Such an electronic component defines for example a three-phase transformer for an isolated voltage converter, such a voltage converter being for example integrated into a component for the electrical supply of a vehicle electrical energy storage unit, also called a “charger” of this electrical energy storage unit. The electrical energy storage unit is for example a battery, which may have a nominal voltage greater than 60V, for example greater than or equal to 300V, 400V, 800V, or even 1000V. The voltage converter receives for example an alternating voltage from an electrical network and supplies the battery with a direct voltage. This converter can convey a power greater than 5kW, for example greater than 7kW, for example greater than 1kW, in particular 22kW or more.

[0003] An electronic component forming for example such a transformer comprises in a known manner:

[0004] - a housing, having a body,

[0005] - a magnetic circuit,

[0006] - two electrical conductors each having a portion arranged around the same part of the magnetic circuit, each of said portions forming between a first and a second end a winding, these two windings being in inductively coupled with each other via the magnetic circuit, and

[0007] - a support for the two electrical windings, arranged between said conductors electrical and said portion of the magnetic circuit,

[0008] the magnetic circuit and the support being received in the body and this body being closed by an electronic card to which the electrical conductors are connected.

[0009] Such an assembly is complex and requires the electronic card to be placed above the body, which generates constraints for placing the electronic component in its environment. Furthermore, the presence of the electronic card above the body makes the presence of a cooling channel carrying liquid more complex. to cool the part of the electronic component adjacent to this electronic card. This results in significant heating of this part of the component, the cooling of which

[0010] by a cooling channel carrying liquid arranged at the other end of the component proves to be insufficient, hence a risk of degradation of this component.

[0011] There is a need to remedy all or part of the aforementioned drawbacks. The invention aims to meet this need and achieves this, according to one of its aspects, using an electronic component, comprising:

[0012] - a housing having a body and a cover, the cover being able to come opposite of an electronic card,

[0013] - a magnetic circuit,

[0014] - two electrical conductors each having a portion arranged around the same part of the magnetic circuit, each of said portions forming between a first and a second end a winding, these two windings being in inductively coupled with each other via the magnetic circuit,

[0015] - a support for the two electrical windings, arranged between said conductors electrical and said part of the magnetic circuit, the support extending along an axis, and

[0016] - a cooling circuit externally bathing at least the area of ​​the body of the housing axially furthest from the cover,

[0017] characterized in that it comprises at least one extension connected to the cover and extending axially along all or part of the magnetic circuit in the direction of said area of ​​the body.

[0018] According to the invention, the extension acts as a radiator to dissipate the heat existing at the part of the electronic component, namely the magnetic circuit and the electrical conductors, adjacent to the cover, towards the cooling circuit arranged at the other end of the component. It is thus possible to maintain the arrangement of the electronic card above the component, while cooling the part of this component closest to this electronic card.

[0019] As will be seen later, the cover and the extension can be made from a single piece, for example from metal such as aluminum.

[0020] The extension may extend axially along the entire magnetic circuit.

[0021] For the purposes of the present application, "axially" and "longitudinally" mean "parallel to the longitudinal axis of the support".

[0022] Alternatively, the extension does not extend the entire length of the magnetic circuit, but extends a sufficient length to dissipate heat to the cooling circuit.

[0023] The extension can be extended by a return allowing the cover to be attached to the magnetic circuit. The extension and the return form, for example, an elbow. Thus, the extension not only acts as a radiator, but also helps to hold the cover on the magnetic circuit.

[0024] The extension and the return, as well as the cover where appropriate, can be made from a single piece, for example from a metal such as aluminum.

[0025] The return can define an angle between 70° and 90° with the extension, when the cover is hooked onto the magnetic circuit.

[0026] In all of the above, the extension may have one or more cutouts configured to provide flexibility to said extension. This or these cutouts are for example provided in the longitudinal edges of the extension. These may be cutout(s) extending axially and / or cutout(s) extending transversely relative to the axis.

[0027] In all of the above, the extension may comprise a proximal portion adjacent to the cover and a distal portion, these distal and proximal portions being offset from each other and connected by a connecting portion extending transversely to the axis of the support. The aforementioned cutouts may be arranged at the junction zone between the connecting portion and the proximal portion. The connecting portion makes it possible, for example, to bring the extension closer to the magnetic circuit.

[0028] The proximal portion may have a transverse dimension greater than that of the distal portion.

[0029] In all of the above, the return may be received in a space provided in the magnetic circuit.

[0030] In all of the above, the support may also incorporate a system for holding it on the body of the housing. This system for holding it on the body of the housing comprises, for example, a pin, in particular a pin having a cross-section perpendicular to the longitudinal axis of the support, extending axially away from the rest of the support. This pin may be forced into an opening provided in the body of the housing. In such a case, the return may be arranged in the axial space existing between the magnetic circuit and the bottom wall of the housing, a space in which the pin extends from the support towards this bottom wall of the housing.

[0031] In all of the above, the extension may be arranged inside the body of the housing. The extension is for example in contact or in the immediate vicinity of the wall of the body of the housing. Such an arrangement of the extension may promote the dissipation of heat towards the cooling circuit partially bathing the body of the housing.

[0032] At least the bottom wall of the housing body, which here defines the area of ​​the body axially furthest from the cover, and at least a fraction of the wall of the housing body extending along the magnetic circuit are, for example, bathed by the cooling circuit. The latter is, for example, traversed by a liquid such as glycolated water.

[0033] The component is for example contained in a box of the cooling circuit, this box having an inlet and an outlet for the cooling fluid. In the case where this fluid is a liquid such as glycolated water, this box is commonly called a “water box”.

[0034] In all of the above, the electronic component may define a transformer for an isolated voltage converter.

[0035] The transformer is for example a three-phase transformer for an isolated voltage converter, comprising three supports for electrical conductors, each support being arranged around a part of the magnetic circuit and carrying two windings in inductive coupling with each other via the magnetic circuit, the supports defining in particular a geometric pattern being a triangle, in particular an equilateral triangle.

[0036] Each support thus carries two windings in inductive coupling with each other, together defining a phase of the three-phase transformer.

[0037] The arrangement of the three electrical conductor supports according to an equilateral triangle can ensure a balance between the electrical parameters such as the inductances of the electrical windings and reduce the magnetic volume.

[0038] The magnetic circuit can be made up of two parts, each part defining a base carrying pins, two by two superimposed when these two parts are assembled, and the superposition of two pads defines the part of the magnetic circuit on which a support of two electrical conductors is mounted.

[0039] The voltage converter comprises for example the aforementioned electronic card, and the electrical conductors can be electrically connected to electrical tracks of this card, where appropriate through the cover and / or through the electronic card.

[0040] Several extensions are for example possible, for example two or three extensions and not just one. In this case, the extensions, possibly extended by returns, can be distributed uniformly when moving around the triangle defined by the transformer.

[0041] The invention also relates, according to another of its aspects, to a component for the electrical power supply of a vehicle electrical energy storage unit, comprising the transformer defined above. The electrical energy storage unit is for example a battery which may have one of the above nominal voltages.

[0042] The invention may be better understood by reading the following description of non-limiting examples of its implementation:

[0043] - [Fig.l] schematically represents part of the electrical circuit of a component for the power supply of a vehicle electrical energy storage unit,

[0044] - [Fig.2] represents a three-phase transformer not covered by the claims but useful for understanding the invention, and

[0045] - [Fig.3] represents similarly to [Fig.2] an example of a three-phase transformer in which the invention is implemented.

[0046] [Fig.l] shows a part of the electrical circuit 1 of a component for the electrical power supply of a vehicle electrical energy storage unit. This component is also called a “charger”. The electrical energy storage unit, not shown in this [Fig.l], is for example a battery, which may have a nominal voltage greater than 60V, for example greater than or equal to 300V, 400V, 800V, or even 1000V.

[0047] The circuit 1 receives as input an alternating voltage from a network (not shown) which is three-phase here. A rectifier for converting this alternating voltage into a direct voltage, and also performing, if necessary, a power factor correction function, is arranged upstream of a direct bus 11. Downstream of this direct bus, from the electrical network, is arranged an isolated voltage converter 12, here being a DC / DC. This converter 12 comprises, in a known manner, an inverter 14, a three-phase transformer 15, and a rectifier 16 supplying the vehicle with a direct voltage isolated from the electrical network. As can be seen in [Fig.l], the three-phase transformer 15 is connected to each of the rectifier 16 and the inverter 14 by an inductor block 17 and a capacitor block 18, so as to define a CLLLC structure.Other structures are of course possible, such as an LLC, CLLC, LC or even CL structure.

[0048] As can be seen in [Fig.l], each phase has a primary winding 20 and a secondary winding 21 in inductive coupling with each other, and the primary windings 20 are connected in star and the secondary windings 21 are also connected in star.

[0049] As understood from [Fig. 3], the three-phase transformer 15 comprises in the example considered a magnetic circuit 22, comprising a first part 23 and a second part 24. Each part 23, 24 comprises: a base 26 of substantially triangular outline, and three pads 27 each extending in the direction of the base 26 of the other part of the magnetic circuit 22. Each base 26 here has an outline defining an equilateral triangle.

[0050] The transformer 15 further comprises three supports 30 for electrical conductors 31, 32, each support 30 being here mounted on two facing pads 27 belonging respectively to one and the other of the parts 23, 24 of the magnetic circuit. Two electrical conductors 31, 32 associated with the same support 30 respectively have a portion defining a primary winding 20 and a portion defining a secondary winding 21. These electrical conductors 31, 32 are for example Litz wire.

[0051] As can be seen in [Fig.3], the three supports 30 of electrical conductors 31, 32 are positioned so as to define an equilateral triangle.

[0052] The transformer 15 also comprises a housing 50 not visible in [Fig.3] but which may be similar to that shown in [Fig.2], this housing comprising a body 51 closed by a cover 52 above which is arranged an electronic card 53. This electronic card 53 is located above the transformer 15, and it carries electrically conductive tracks allowing connection via the terminals 59 of the transformer 15 to the rest of the electrical circuit 1 shown in [Fig.l].

[0053] As can be seen in [Fig. 3], the electrical connections of the electrical conductors 31, 32 to the electronic card 53 are made for example through cutouts made in the cover 52 and through openings made in the card 53.

[0054] The body 51 is for example made of metal, for example aluminum. The supports 30 and the magnetic circuit 22 are arranged inside the housing 50. The body 51 is filled with a resin capable of being polymerized to harden and immobilize the components arranged inside the body ("potting" in English).

[0055] As can be guessed from [Fig. 3], the housing 50 also has a triangular outline, being more precisely here an equilateral triangle. The housing is in the example considered exclusively formed by the body 51 and the cover 52, but the invention is not limited to a housing 50 consisting of two parts.

[0056] As can be seen in [Fig.3], each pad 27 defines its own air gap 28, for example via an area of ​​the pad 27 filled with non-magnetic material such as a fiberglass-reinforced epoxy resin composite (FR4) or ceramic. This area occupied by this non-magnetic material defines, for example, an entire section of the pad. Several sections are, for example, assembled with this area of ​​the pad 27 to constitute this pad 27.

[0057] As can be seen in [Fig.3], an additional air gap 29 is present between the opposite ends of two pads 27 belonging respectively to different parts 23, 24 of the magnetic circuit 22. Thus, in the example of magnetic circuit 22 considered, each magnetic field allowing the inductive coupling between a primary winding 20 and a secondary winding 21 crosses exactly three air gaps.

[0058] Still in [Fig. 3], it can be seen that the magnetic circuit 22 of the example considered comprises a central leg 40 carried by one of the parts 23, 24 of the magnetic circuit 22. This central leg 40 is here made in a single piece with the part 23 of the magnetic circuit 22 which carries it.

[0059] The magnetic circuit 22 and, where appropriate, the supports 30 for electrical conductors are, for example, produced in accordance with the teaching of the application. filed in France on December 7, 2022 under number 22 12970.

[0060] It can be seen in [Fig. 2] that the transformer 15 is received inside a box 60 of a cooling circuit 61. This cooling circuit 61 is for example traversed by liquid such as glycolated water. The box 60, also called a “water box”, has an inlet 62 and an outlet 63 for the cooling fluid.

[0061] The cooling liquid bathes, similarly to what is shown in [Fig.2], externally all or part of the body, at least the zone 55 of the body axially furthest from the cover, which can constitute a bottom wall of this body 51.

[0062] In the example of [Fig.2], and also in the example of [Fig.3] although not shown in this [Fig.3], the liquid bathes the bottom wall 55 and the wall 56 of the body 51 of the housing 50 extending along the magnetic circuit 22.

[0063] As can be seen in [Fig. 3], and according to the invention, the transformer 15 comprises an extension 70 connected to the cover 52. This extension 70 extends axially along all or part of the magnetic circuit 22 in the direction of the bottom wall 55 of the body 51. This extension 70 acts as a radiator to dissipate the heat existing at the level of the magnetic circuit 22 and the electrical conductors 31, 32 opposite the cover 52 towards the cooling circuit 61.

[0064] In the example shown, the cover 52 and the extension 70 are made from a single piece, here made of aluminum. Although not visible in [Fig. 3], several extensions 70 may be provided, for example three extensions 70 distributed uniformly around the cover 52.

[0065] It can also be seen in [Fig. 3] that the extension 70 can extend axially along the entire length of the magnetic circuit 22. As shown in [Fig. 3], the extension 70 can be extended by a return 71 allowing the cover 52 to be attached to the magnetic circuit 22. The extension 70 and the return 71 here form an elbow, the angle formed between these two elements being, for example, between 70° and 90°.

[0066] Still in the embodiment described, but in a non-limiting manner, the extension 70 and the return 71 are made from a single piece, here made of aluminum. As can be seen in [Fig. 3], the extension 70 has several cutouts configured to give flexibility to said extension. Thanks to this flexibility, the extension 70 can occupy different successive positions when the return 71 is attached to the magnetic circuit 22, as visible in [Fig. 3]. Two cutouts 75 are for example formed in the longitudinal edges of the extension 70, namely a cutout 75 on each edge extending towards the other edge, and the bottom of these cutouts accommodates for example a cutout 76 extending axially towards the cover 52.

[0067] It can also be seen in [Fig.3] that the extension 70 is not necessarily plane. It can thus include:

[0068] -a proximal portion 77 adjacent to the cover 52, and

[0069] - a distal portion 78 adjacent to the return 71.

[0070] It can be seen in [Fig. 3] that these distal 78 and proximal 77 parts are offset from each other and connected by a connecting part 79 extending transversely to the axis of the support 30 of electrical conductors. The proximal part 77 is further from the magnetic circuit 22 than the distal part 78, in order to allow the bend existing between the cover 52 and the extension 70. Still in [Fig. 3], it can be seen that the cutouts 75 and 76 can be arranged at the junction zone between the connecting part 79 and the proximal part 77.

[0071] It can also be seen in [Fig. 3] that the proximal part 77 may have a transverse dimension greater than that of the distal part 78.

[0072] Although not shown, the extension 70 and the return 71 are here arranged inside the body 51 of the housing 50. The extension 70 is advantageously in contact or in the immediate vicinity of the wall 56 of the body of the housing, to evacuate the heat towards the liquid present in the box 61.

[0073] The return 71 is for example received in an empty axial space arranged between the bottom wall 55 of the body 51 and the lower face of the magnetic circuit 22. Pins ensuring that the magnetic circuit is held on the body 51 extending for example from the supports 30 towards the bottom wall 55 in this axial space.

[0074] Alternatively, a cutout may be provided in the lower base 26 of the magnetic circuit 22 to receive the return 71.

[0075] In all of the above, the cover 52 can be held on the body 51 via the magnetic circuit 22, namely by the combination:

[0076] - of a hooking of the cover 52 on the magnetic circuit 22 via the extension 70 and return 71, and

[0077] - maintaining the magnetic circuit 22 on the body 51 via the aforementioned pins, or any other attachment of the magnetic circuit to the body 51.

[0078] Alternatively, another attachment of the cover 52 to the body 51 is possible, for example direct attachment by screws.

[0079] The invention is not limited to what has just been described.

Claims

Claims

1. Electronic component (15), comprising: - a housing (50) having a body (51) and a cover (52), the cover being able to come opposite an electronic card (53), - a magnetic circuit (22), - two electrical conductors (31, 32) each having a portion arranged around the same part (27) of the magnetic circuit, each of said portions forming between a first and a second end a winding, these two windings being in inductive coupling with each other via the magnetic circuit, - a support (30) of the two electrical windings, arranged between said electrical conductors (31, 32) and said part (27) of the magnetic circuit, the support extending along an axis, and - a cooling circuit (61) externally bathing at least the zone of the body (55) axially furthest from the cover (52),characterized in that it comprises at least one extension (70) connected to the cover (52) and extending axially along all or part of the magnetic circuit (22) in the direction of said zone (55) of the body.,

2. Component according to claim 1, the extension (70) extending axially along the entire length of the magnetic circuit (22).

3. Component according to claim 2, the extension (70) being extended by a return (71) allowing the cover (52) to be attached to the magnetic circuit (22).

4. Component according to any one of the preceding claims, the cover (52), the extension (70) and the return (71) being made in one piece.

5. Component according to claim 3 or 4, the return (71) defining an angle between 70° and 90° with the extension (70), when the cover (52) is hooked onto the magnetic circuit (22).

6. A component according to any preceding claim, the extension (70) having one or more cutouts (75, 76) configured to provide flexibility to said extension (70).

7. Component according to any one of the preceding claims, the extension (70) comprising a proximal portion (77) adjacent to the cover (52) and a distal portion (78), these distal (78) and proximal (77) portions being offset from each other and connected by a connecting portion (79) extending transversely to the axis of the support.

8. A component according to any preceding claim, the extension (70) being disposed within the body (51) of the housing (50).

9. A component according to any preceding claim, defining a transformer (15) for an isolated voltage converter.

10. Component according to the preceding claim, defining a three-phase transformer for an isolated voltage converter, comprising three supports (30) of electrical conductors, each support being arranged around a part of the magnetic circuit and carrying two windings in inductive coupling with each other via the magnetic circuit, the supports defining in particular a geometric pattern being a triangle, in particular an equilateral triangle.

11. Component (12) for the electrical power supply of a vehicle electrical energy storage unit, comprising the transformer according to one of claims 9 or 10.

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