Electrical equipment comprising a busbar cooled by two faces of a heatsink

Abstract

The present invention relates to electrical equipment, wherein: - A heat sink comprising an internal volume defined by at least two opposing faces; and -Bus bar(4); Includes, The above bus bar (4) comes into contact with the two opposing surfaces of the heat sink in a manner that is cooled by the heat sink.

Description

Technology Field

[0001] The present invention relates particularly to the field of electrical equipment for electric or hybrid vehicles, and more precisely to the cooling of electrical systems, such as inverters connected to motors in electric motorization systems. Background Technology

[0002] It is known that electrical equipment equipped with bus bars is used. In particular, these bus bars are intended to transfer electrical energy from the interfaces of the electrical equipment, specifically from external interfaces, to the internal components of the electrical equipment. For example, a bus bar connects the terminals of the electrical equipment to the capacitors of the electrical equipment. A bus bar typically comprises a lead frame, made particularly of metal, which is supported by a body made of electrical insulating material, particularly plastic. Electronic components may be housed in the bus bar to filter the signal flowing through the lead frame. While current passes through the bus bar, heat released from the electrical conductors and / or filtering components can damage other components of the electrical equipment, particularly capacitors, which already generate heat due to the Joule effect caused by their own operation.

[0003] It is known that to cool the bus bar, the bus bar is passed through a cooling box equipped with a system for circulating coolant. However, this may not be sufficient, especially when the electrical equipment operates at high voltage, i.e., voltages of 60V or higher, or even 80V, 100V, 400V, or 800V. In particular, the electrical equipment may operate between 50kW and 300kW.

[0004] Therefore, a cooling solution capable of improving heat dissipation of the lead frame is required. means of solving the problem

[0005] For this purpose, electrical equipment comprising the following is proposed, and such electronic equipment is:

[0006] - A heat sink comprising an internal volume defined by at least two opposing faces;

[0007] -Bus bar;

[0008] Includes,

[0009] The above bus bar comes against the two opposing surfaces of the heat sink in a manner that is cooled by the heat sink.

[0010] Accordingly, the bus bar is cooled by two opposing surfaces of the heat sink. In the prior art, only one surface of the heat sink is used to cool the bus bar. Therefore, thanks to the integration of the bus bar and the heat sink, the cooling of the bus bar is increased compared to the prior art. In particular, the bus bar comes into direct contact with the two opposing surfaces of the heat sink or comes into contact with the opposing surfaces of the heat sink through one or more intermediate layers.

[0011] According to one embodiment, the bus bar extends along two opposing surfaces in a manner that surrounds the heat sink.

[0012] According to one embodiment, the heat sink includes a first side to which the two opposing surfaces are connected, and the bus bar extends from the first side along the heat sink and returns to the first side.

[0013] Alternatively, the input and output terminals of the bus bar are located on the first side of the heat sink.

[0014] Alternatively, the heat sink includes a second side to which the two opposing sides are connected, and the second side faces the first side. The bus bar extends along the heat sink from the first side to the second side, and then from the second side to the first side.

[0015] According to one embodiment, the bus bar comprises two parts assembled together, and in a manner that surrounds the heat sink, the first part contacts the first surface of the heat sink and the second part contacts the second surface of the heat sink.

[0016] According to the alternative, the first and second parts of the bus bar are assembled together at the second edge of the heat sink.

[0017] According to one embodiment, the bus bar is made as a single part surrounding the heat sink.

[0018] According to one embodiment, the bus bar includes a coating surrounding the lead frame, and

[0019] The coating comprises an opening coming across from a portion of the heat sink, and the opening comprises an electrically insulating heat sink material in a manner that improves the cooling of the lead frame.

[0020] According to one embodiment, the bus bar supports at least one electrical component. Alternatively, the electrical component is an EMC filtering component.

[0021] Alternatively, electrical components are sandwiched between the bus bar and the heat sink.

[0022] According to one embodiment, at least one of the surfaces of the heat sink is configured to cool another component on at least one surface that is not covered by the bus bar.

[0023] According to the alternative, the first side of the heat sink accommodates electronic power modules, and the second side of the heat sink accommodates capacitive modules on a surface not covered by bus bars.

[0024] According to an alternative, the heat sink includes at least one cooling channel configured to receive a cooling fluid, and

[0025] The above cooling channel is at least partially located in an area not covered by the bus bar, and there is no cooling channel in the part of the heat sink surrounded by the bus bar. Brief explanation of the drawing

[0026] The invention will be better understood, and other details, features, and advantages of the invention will become clear when reading the following description, given as a non-limiting example with reference to the accompanying drawings. FIG. 1 shows a perspective view of an example of electrical equipment according to the present invention. FIG. 2 shows a perspective view of the electrical equipment of FIG. 1, wherein the bus bar is equipped with components. Figure 3 shows a cross-sectional view of the electrical equipment of Figure 2. Figure 4 shows an exploded view of the electrical equipment of Figure 2. Figure 5 shows a detailed view of an alternative to the electrical equipment of Figure 2. Specific details for implementing the invention

[0027] The electrical equipment (100) as illustrated in FIG. 1 includes a heat sink (2), which comprises an internal volume defined by at least two opposing surfaces (20a, 20b). In the illustrated example, a portion of the heat sink (2), referred to as the main portion (2a), may include a cooling channel (21) configured to receive a cooling fluid. The other portion of the heat sink, referred to as the auxiliary portion (2b), does not have a cooling channel. The auxiliary portion (2b) is cooled particularly by heat conduction from the auxiliary portion (2b) to the main portion (2a), where heat is discharged by the cooling fluid flowing through the cooling channel (21). That is, the auxiliary portion (2b) forms a protrusion of material from the main portion (2a). By not providing a cooling channel in the auxiliary portion (2b), its size and the final size of the electrical equipment (100) are limited. The heat sink (2) may have a substantially rectangular shape. However, the auxiliary part (2b) will increase its size but may accommodate cooling channels to improve heat dissipation in the auxiliary part (2b). However, the auxiliary part (2b) without cooling channels is sufficient for cooling the bus bar, particularly as described below. The auxiliary part (2b) may be made of a different material than the main part (2a). In particular, the auxiliary part (2b) may be made of a material with a higher thermal conductivity than the main part (2a). For example, the main part (2a) is made of aluminum, and the auxiliary part (2b) is made of copper. However, the cost may be substantially higher.

[0028] Two opposing surfaces (20a, 20b) may have substantially the same contour. They may overlap substantially parallel to each other. The contours of the two opposing surfaces (20a, 20b) are connected by a wall (3) specifically along the contours. Alternatively, the contours of the two opposing surfaces may be connected directly between them, specifically without a wall (3). For the positioning of components or the passage of connections, etc., the opposing surfaces (20a, 20b) may include notches, openings, or other differences relative to the other opposing surfaces (20a, 20b).

[0029] The electrical equipment includes a bus bar (4). The bus bar (4) may include two lead frames (41a, 41b), specifically a negative lead frame (41a) and a positive lead frame (41b). The lead frames (41a, 41b) are made of metal, for example, copper. They form a solid part, which is held together by a coating (42) made of an electrical insulating material, for example, by overmolding. In FIG. 1, part of the coating (42) is not shown so that the lead frames (41a, 41b) can be seen. The lead frames (41a, 41b) specifically connect the terminals of the electrical equipment (100) to the capacitors of the electrical equipment (100).

[0030] The bus bar (4) comes into contact with two opposing surfaces (20a, 20b) of the heat sink (2) in such a way that it is cooled by the heat sink (2). Thus, the bus bar (4) has the advantage of being cooled from two surfaces of the heat sink (2). Integrating the bus bar (4) into the electrical equipment (100) is an improvement over the prior art. The cooling of the bus bar (4) is improved while still controlling the size of the electrical equipment (100). The bus bar (4) extends along the two opposing surfaces (20a, 20b) of the heat sink (2) in a way that surrounds the heat sink (2). Thus, the bus bar (4) can be cooled along its entire length. Therefore, the surface area of ​​the bus bar (4) being cooled is increased compared to the prior art. Then, the cooling of the bus bar (4) is higher, and the risk of heat damage is significantly reduced. In addition, by surrounding the heat sink (2), the bus bar (4) is integrated with the heat sink (2).

[0031] In particular, the bus bar (4) starts from the first side (3a) of the heat sink (2); extends along the auxiliary part (2b), particularly along the portion of the first side (20a) included in the auxiliary part (2b). Then, the bus bar (4) joins the second side (20b) by the second side (3b) of the heat sink (2), and continues again along the auxiliary part (2b), particularly along the portion of the second side (20b) included in the auxiliary part (2b), to return to the first side (3a). Thus, the bus bar (4) forms a loop around the heat sink (2), particularly around the auxiliary part (2b). Upon returning to the first side (3a), an electrical connection to the bus bar (4), for example, a connection to a terminal of the electrical equipment (100) or a connection to a capacitor of the electrical equipment (100), can be provided on the same side (3a) of the heat sink. In particular, from an industrial perspective, during the manufacture of the electrical equipment (100), this arrangement makes it easier to connect the bus bar (4). Thus, two connections can be made from the same side of the heat sink (2) without flipping the electrical equipment (100); this allows manufacturing steps and time to be saved. Thus, unnecessary manipulation of the electrical equipment (100) during assembly is prevented, and / or thus quality inspection is facilitated. In particular, the second side (3b) faces the first side (3a). However, this second side (3b) may be the side of the heat sink (2) adjacent to the first side (3a).

[0032] The bus bar (4) specifically comprises two parts (4a, 4b) assembled together in a manner that surrounds the heat sink (2). The first part (4a) contacts the first side (20a) of the heat sink (2); and the second part (4b) contacts the second side (20b) of the heat sink (2). Thus, the assembly of the bus bar (4) around the heat sink (2) can be performed in several stages. In particular, the first part (4a) and the second part (4b) of the bus bar (4) are assembled together at the second side (3b) of the heat sink (2). In particular, the lead frame (41a, 41b) includes a first part that contacts the first side (20a) and a second part that contacts the second side (20b), respectively. For example, as illustrated in FIG. 4, the ends (5a, 5b) of the first part of the lead frame (41a, 41b) are in contact with the respective ends (5c, 5d) of the second part of the lead frame (41a, 41b). These ends (5a, 5b, 5c, 5d) are connected by welding, brazing, screwing, or other fastening means. The arrangement described above enables the assembly of the heat sink (2) and the bus bar (4) along a single axis.

[0033] Alternatively, the bus bar (4) may be a single part surrounding the heat sink (2). The lead frames (41a, 41b) are each a single part and extend continuously, in particular, from the first side (20a) to the second side (20b). Conversely, this alternative makes it possible to save parts and / or pre-assembly steps, such as connecting the first part (4a) and the second part (4b) of the bus bar (4). Additionally, any assembly in the wrong direction is prevented.

[0034] For example, as illustrated in FIG. 5, the coating (42) of the bus bar (4) may include one or more openings (40) facing the heat sink (2). The openings (40) particularly expose the surface of the lead frames (41a, 41b). These openings (40) are filled with an electrical insulating material but conduct heat in a manner that improves the cooling of the lead frames (41a, 41b). The material may be thermally conductive grease or, for example, a "gap pad" ® Alternatively, it may be a flexible material such as any other material having the dual characteristics of electrical insulation and thermal conductivity.

[0035] For example, as illustrated in FIGS. 2, 3 and 4, the bus bar (4) can support components (12, 16), particularly a filtering component (12) and a magnetic core (16) required for filtering. These components (12, 16) can be assembled onto an electronic board (14) that is mounted on the bus bar (4), particularly on the coating (42) of the bus bar (4). The electronic board (14) accommodates electrical components, especially small ones, that are difficult to assemble directly onto the bus bar (4). Filtering makes it possible to reduce the EMC electromagnetic field connected to the current flowing through the bus bar (4) in order to protect the components of the electrical equipment (100). Other components may be placed on other electronic boards and connected to the bus bar (4) by cables, bundles, or rigid connectors.

[0036] Alternatively, the parts (12, 16) can be mounted directly onto the bus bar (4) without an intermediary of the electronic board (14). In this case, the parts (12, 16) can be welded, brazed, or fixed onto the bus bar (4) by other fixing methods.

[0037] In particular, the bus bar (4) contacts the heat sink (2) at the auxiliary portion (2b) of the heat sink (2). The bus bar (4) covers only one area on the heat sink (2). Preferably, the bus bar (4) covers only one area of ​​the auxiliary portion (2b). The remaining portion of the heat sink (2), particularly the first surface (20a) and the second surface (20b) located in the main portion (2a), may accommodate other components to cool them. For example, in FIG. 1, the opening (22) in the first surface (20a) of the heat sink (2) is closed by a plate carrying an electronic power module. By closing the opening (22) in the first surface (20a), the plate contributes to forming a cooling channel located particularly in the main portion (2a) of the heat sink (2). For example, as shown in FIG. 4, a portion (201b) of the second surface (20b) located in the main part (2b) can accommodate a capacitor to be cooled by the main part (2a). Since power modules and capacitors generally emit a lot of heat due to the Joule effect, it is advantageous to place them in the main part (2a) of the heat sink.

[0038] In an alternative not illustrated, the component (12, 16) can be sandwiched between the bus bar (4) and the heat sink (2), which improves the cooling of the component (12, 16). In this particular case, the structure of the face (20a, 20b) of the heat sink (2) can be configured to fit the size of the component (12, 16). The surface of the heat sink (2) that the component (12, 16) contacts can accommodate different heights and shapes of the component (12, 16) to ensure its cooling. For example, starting from the heat sink (2), there is first a flexible material layer (42) that is electrically insulating but thermally conductive, then the component (12, 16), followed by the electronic board (14) and the bus bar (4). This sandwich-type arrangement also allows the component (12, 16) to be securely fixed. Degradation due to vibration is reduced. The lifespan of the electrical equipment (100) is increased.

Claims

Claim 1 Electrical equipment (100) comprising: - a heat sink (2) having an internal volume defined by at least two opposing surfaces (20a, 20b); and - a bus bar (4); wherein the bus bar (4) abuts the two opposing surfaces (20a, 20b) of the heat sink (2) in a manner that is cooled by the heat sink (2), the heat sink (2) includes a first side (3a) to which the two opposing surfaces (20a, 20b) are connected, and the bus bar (4) extends from the first side (3a) along the heat sink (2) and returns to the first side (3a). Claim 2 In claim 1, the bus bar (4) is an electrical device (100) that extends along two opposing surfaces (20a, 20b) in a manner that surrounds the heat sink (2). Claim 3 delete Claim 4 In claim 1 or 2, the input terminal and output terminal of the bus bar (4) are electrical equipment (100) located on the first side (3a) of the heat sink (2). Claim 5 In claim 1 or 2, the heat sink (2) comprises a second side (3b) to which the two opposing sides (20a, 20b) are connected, the second side (3b) is opposite to the first side (3a), and wherein the bus bar (4) extends along the heat sink (2) from the first side (3a) to the second side (3b) and then from the second side (3b) to the first side (3a), electrical equipment (100). Claim 6 Electrical equipment (100) comprising: - a heat sink (2) having an internal volume defined by at least two opposing surfaces (20a, 20b); and - a bus bar (4); wherein the bus bar (4) abuts the two opposing surfaces (20a, 20b) of the heat sink (2) in a manner that is cooled by the heat sink (2), and the bus bar (4) comprises two parts (4a, 4b) assembled together, wherein the first part (4a) abuts the first surface (20a) of the heat sink (2) and the second part (4b) abuts the second surface (20b) of the heat sink (2) in a manner that surrounds the heat sink (2). Claim 7 In claim 6, the first part (4a) and the second part (4b) of the bus bar (4) are electrical equipment (100) assembled together on the second side (3b) of the heat sink (2). Claim 8 Electrical equipment (100) comprising: - a heat sink (2) having an internal volume defined by at least two opposing surfaces (20a, 20b); and - a bus bar (4), wherein the bus bar (4) is in contact with the two opposing surfaces (20a, 20b) of the heat sink (2) in a manner that is cooled by the heat sink (2), and the bus bar (4) is manufactured as a single part surrounding the heat sink (2). Claim 9 Electrical equipment (100) comprising: - a heat sink (2) having an internal volume defined by at least two opposing surfaces (20a, 20b); and - a bus bar (4); wherein the bus bar (4) abuts the two opposing surfaces (20a, 20b) of the heat sink (2) in such a manner that the bus bar (4) is cooled by the heat sink (2), and the bus bar (4) comprises a coating (42) surrounding a lead frame (41a, 41b), and the coating (42) comprises an opening (40) extending across a portion of the heat sink (2), and the opening (40) comprises an electrically insulating heat sink material in such a manner that the cooling of the lead frame (41a, 41b) is improved. Claim 10 Electrical equipment (100) comprising: - a heat sink (2) having an internal volume defined by at least two opposing surfaces (20a, 20b); and - a bus bar (4); wherein the bus bar (4) abuts the two opposing surfaces (20a, 20b) of the heat sink (2) in such a manner that the bus bar (4) is cooled by the heat sink (2), and at least one of the opposing surfaces (20a, 20b) of the heat sink (2) is configured to cool another component on at least one surface that is not covered by the bus bar (4). Claim 11 In claim 10, the heat sink (2) comprises at least one cooling channel (21) configured to receive a cooling fluid, and the cooling channel (21) is at least partially located in an area not covered by the bus bar (4), and the part of the heat sink (2) surrounded by the bus bar (4) has no cooling channel.

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