Power module comprising an AMB substrate

Abstract

The invention relates to a power module (10) comprising an AMB substrate (14). A cooler (42) is provided through which a cooling medium (38) flows in a flow direction (40). A number of pin-like heat sinks (52) are formed on an insert (48), said heat sinks protruding with or without coating into the flowing cooling medium (38). The invention further relates to the use of the power module (10) in power electronics or in an inverter of an electric drive of a passenger vehicle or utility vehicle.

Description

[0001] R.415302

[0002] - 1 -

[0003] Description

[0004] title

[0005] Power module with an AMB substrate

[0006] Technical field

[0007] The invention relates to a power module comprising an AMB substrate and a cooler through which a cooling medium flows in one direction. Furthermore, the invention relates to the use of the power module in power electronics or an inverter of an electric drive for a passenger vehicle or a commercial vehicle.

[0008] State of the art

[0009] DE 102014 219998 B4 discloses a power module, in particular for providing a phase current for an electric motor. The power module comprises a circuit carrier with a surface, at least one first contact surface on the surface, and at least one first power transistor, each having a ground contact surface. Each first power transistor is directly arranged on one of the first contact surfaces and electrically connected to the first contact surface via its ground contact surface. The power module also comprises a second contact surface on the surface and at least one second power transistor, each having a ground contact surface. The at least one second power transistor is directly arranged on the second contact surface and electrically connected to the second contact surface via its respective ground contact surfaces.Furthermore, the power module includes third contact surfaces on the surface, wherein at least one second power transistor has one further contact surface on each of its sides facing away from the surface of the circuit carrier, and each second power transistor has a third contact surface via a further contact surface R.415302.

[0010] - 2 -

[0011] The surfaces are electrically connected. The first contact surface and at least one third contact surface are arranged alternately one after the other in a longitudinal direction of the power module, and the second contact surface is arranged next to the first contact surface and the at least one third contact surface, wherein the second contact surface has at least two contact areas, one of which is located next to each first power transistor. The at least one first power transistor has a further contact surface on its side facing away from the surface of the circuit carrier, and each first power transistor is electrically connected via its further contact surface to the contact area of ​​the at least two contact areas of the second contact surface located next to it.In this arrangement, at least two contact areas of the second contact surface and at least one second power transistor are arranged alternately one after the other in the longitudinal direction.

[0012] DE 102022 206 265.5 relates to a power module with a first circuit carrier having an electrically insulating layer on which at least one first conductor structure, at least one second conductor structure, and at least one third conductor structure are formed, wherein at least one first semiconductor switch is electrically connected between the at least one first conductor structure and the at least one third conductor structure. At least one second semiconductor switch is electrically connected between the at least one third conductor structure and the at least one second conductor structure, wherein at least one second circuit carrier is arranged spatially parallel above the first circuit carrier.This has at least one internal contact area and at least one external contact area, wherein the layout of the first circuit carrier is mirror-symmetrical to a central longitudinal axis, and wherein the second circuit carrier is designed as a rectangular and, in particular, flexible printed circuit board, which is arranged symmetrically to the central longitudinal axis and is connected to the first circuit carrier via soldered connections, welded connections, adhesive connections, or sintered connections.

[0013] Disclosure of the invention

[0014] According to the invention, a power module is proposed which has an AMB substrate and further a cooler which is supplied by a cooling medium in a R.415302

[0015] - 3 -

[0016] The flow direction is through which the material flows. A number of pin-shaped cooling elements are formed on an insert embedded in the mold material; these elements, coated or uncoated, protrude into the flowing cooling medium.

[0017] Advantageously, the solution proposed according to the invention can achieve a reduction in the thermal resistance between the components of a power electronics system and the cooling medium, since the number of layers is significantly reduced.

[0018] In the power module proposed according to the invention, the pin-shaped heat sinks are, for example, additively manufactured on the insert using a 3D printing process. Alternatively, the pin-shaped heat sinks can also be manufactured by wire bonding, attached pins, or brazing.

[0019] In an advantageous further development of the power module proposed according to the invention, the pin-shaped heat sinks are provided with an electroplated nickel plating or an electroless nickel coating. The aforementioned electroplated nickel plating or electroless nickel coating may be necessary due to the electrochemical series.

[0020] Furthermore, in the power module proposed according to the invention, a mold material, sealed via sealing elements, is inserted into a mounting opening of the cooler.

[0021] The power module proposed according to the invention is further characterized in that the mold material above the insert has a number of incisions which increase the surface area of ​​the mold material and which are trapezoidal, triangular, rectangular or semicircular in shape.

[0022] This allows for an advantageous improvement in the dissipation of waste heat generated during the operation of the power module.

[0023] Furthermore, in the power module proposed according to the invention, the cooling medium flows directly around the pin-shaped cooling elements outside the mold material. R.415302

[0024] - 4 -

[0025] In an advantageous embodiment of the power module proposed according to the invention, the pin-shaped cooling elements, whether coated or uncoated, project into a cooling channel that is located within the mold material. This solution offers significant manufacturing advantages, as it eliminates the need for additional components and piping.

[0026] In an advantageous further development, the cooling channel is formed by a fixed component that delimits the cooling channel and seals it via at least one seal, and is received on the mold material by means of connecting elements in a force-fit, form-fit or material-fit manner.

[0027] In a further embodiment of the power module according to the invention, the mold material, together with the underlying sheet metal part that defines the cooling channel, is received on dome-shaped projections in the housing by means of clamping plates or hold-downs. By arranging the mold material, on the underside of which the insert with the pin-shaped cooling channel extending from it is received, the mold material and the insert are decoupled within the housing of the power module.

[0028] In a further advantageous embodiment of the power module proposed according to the invention, the insert is embedded in the mold material, and the sheet metal part bounding the cooling channel is bonded to a copper sheet using a fixing adhesive and a sealant. The arrangement of the copper sheet advantageously ensures improved heat dissipation.

[0029] Furthermore, in this embodiment of the power module proposed according to the invention, the copper sheet is bonded to one side of the AMB substrate, in particular preferably to its underside.

[0030] Furthermore, in this embodiment of the power module proposed according to the invention, the fixing adhesive and / or the sealing adhesive are arranged in wave-like, complementary deformations of the sheet metal part and the copper sheet. Improved heat dissipation can be achieved through the wave-like, complementary deformations in both the sheet metal part and the copper sheet. R.415302

[0031] - 5 -

[0032] In a further advantageous embodiment of the power module proposed according to the invention, the cooling channel through which the cooling medium flows is joined, in particular welded, to a perforated sheet extending below the A MB substrate in a materially bonded manner.

[0033] Furthermore, in this design variant, it can also be provided that a layer of spacer material runs between the AMB substrate and the perforated sheet.

[0034] In a further embodiment of the power module proposed according to the invention, a plastic tray defining the cooling channel is joined to a plastic part via at least one hot-joint connection below the AMB substrate of the insert embedded in the mold material.

[0035] Furthermore, the invention relates to the use of the power module in a power electronics / inverter of an electric drive of a passenger vehicle or a commercial vehicle.

[0036] Advantages of the invention

[0037] The solution proposed according to the invention allows the number of layers within a power electronics component to be reduced, thus significantly lowering the thermal resistance between the heat-generating components of the power electronics and the cooling medium. This is achieved by applying pin-shaped heat sinks, printed directly onto the heat-generating substrate, for example, the AMB substrate, using an additive manufacturing process such as 3D printing, preferably selective laser melting (SLM). The heat sinks proposed according to the invention, preferably additively formed on an insert embedded in the material of a mold body, can be very effectively integrated into the cooling circuit of a cooling medium within cooling channels.The greater the length of the pin-shaped cooling elements that are wetted by the flowing cooling medium, the more effective the heat dissipation or heat transfer to the cooling medium can be achieved. This is especially true when using R.415302.

[0038] - 6 -

[0039] In addition to additively constructed pin-shaped heat sinks and direct heat dissipation into the cooling medium flowing around them, other design concepts are also possible, for example in the form of cooling channels made of plastic material or plastic trays that can be integrated into the housing of the power module.

[0040] Brief description of the drawings

[0041] Embodiments of the invention are explained in more detail with reference to the drawings and the following description.

[0042] They show:

[0043] Figure 1 shows a power module with a multi-layered structure, in which the thermal resistance is relatively high due to the many layers.

[0044] Figure 2 shows a first embodiment of the power module proposed according to the invention with pin-shaped heat sinks,

[0045] Figure 3 shows a further embodiment of the solution proposed according to the invention,

[0046] Figure 4 shows an embodiment of the power module proposed according to the invention, in which the mold body has trapezoidal incisions to increase the surface area,

[0047] Figures 5.1 and 5.2 show embodiment variants of spring-loaded connecting elements that are joined by material bonding to a sheet metal part that borders the cooling channel.

[0048] Figure 6 shows a variant embodiment of fixing the mold material, insert, and cooling channel attached to the mold material on arc-shaped protrusions within the housing.

[0049] Figures 7.1 and 7.2 show a variant embodiment of a cooling channel that is integrated directly into the mold material, R.415302

[0050] - 7 -

[0051] Figure 8 shows an embodiment of the power module in which the pin-shaped heat sinks protrude into a cooling channel which is bounded by a sheet metal part which is attached to a copper sheet using fixing and sealing adhesive.

[0052] Figure 9 shows a variant embodiment of a cooling channel, which is formed as a hard-brazed cooling channel made of aluminium material with a perforated sheet and

[0053] Figure 10 shows a variant embodiment of the cooling channel, in which it is bounded by components made of plastic material.

[0054] Figure 1 shows a power module 10, which comprises a mold body made of a molding material 12 applied to an AMB substrate 14. This substrate is mounted on the top side of a base plate 20 by means of a soldering material 16 and a coating 18. Turbulence grids 24, also connected via soldering material 16, are located below the base plate 20 and are likewise connected to a base plate 28 via soldering material 16 on their underside. A stiffening plate 32 extends below the base plate 28 and is also connected to it via soldering material 16.

[0055] Overall, the structure according to Figure 1 has a high number of layers, which significantly increase the thermal resistance between a cooling medium and the power electronics, in particular the AMB substrate 14 of the power module 10.

[0056] Embodiments of the invention

[0057] In the following description of embodiments of the invention, identical or similar elements are designated by the same reference numerals, and repeated descriptions of these elements are omitted in individual cases. The figures represent the subject matter of the invention only schematically.

[0058] Figure 2 shows a first embodiment of the power module 10 proposed according to the invention. In this R.415302

[0059] - 8 -

[0060] In one embodiment of the power module 10, an insert 48 is embedded in the mold material 12. A number of pin-shaped heat sinks 52 are formed on this insert, particularly by an additive manufacturing process such as 3D printing. Figure 2 further shows that the additively manufactured pin-shaped heat sinks 52 on the insert 48 are either coated with deposited electroplated nickel 54 or with a chemical nickel coating 50. The pin-shaped heat sinks 52 project into a cooling medium 38 (not shown in detail here), which dissipates waste heat. The mold body made of mold material 12, shown in Figure 2, is inserted into the cooler 42 via the sealing elements 46 and sealed above the mounting opening 44.

[0061] The representation according to Figure 2 further shows that the pin-shaped cooling elements 52, which are manufactured using an additive manufacturing process, such as 3D printing, extend essentially from the underside of the insert 48 into the cooling medium 38.

[0062] Figure 3 shows another embodiment of the pin-shaped cooling elements 52, manufactured using an additive manufacturing process such as 3D printing, which in this embodiment are uncoated. In the embodiment shown in Figure 3, the pin-shaped cooling elements 52 also extend essentially from the underside of the insert 48 into the cooling medium 38. Here, too, the mold body made of mold material 12 is received in the mounting opening 44 of the cooler 42 by means of the sealing element 46. Furthermore, Figure 3 shows a seal 58, the corner radii R of which are indicated by reference numeral 56.

[0063] In the embodiment schematically depicted in Figure 4, a mold body made of mold material 12 is shown, which is mounted on a base 60. The mold body made of mold material 12 is subjected to a flow of cooling medium 38 laterally in the direction of flow 50 and passes over the pin-shaped cooling elements 52 projecting from the underside of the mold body made of mold material 12, which are uncoated in this embodiment. Here, too, the pin-shaped cooling elements 52 are formed on the underside of an insert 58, which is embedded in the mold material 12 of the mold body. The pin-shaped cooling elements 52 projecting from the underside of the mold body made of mold material 12 extend into the laterally flowing cooling medium 38.

[0064] - 9 -

[0065] into and consequently dissipate waste heat. In the embodiment shown in Figure 4, trapezoidal incisions 64 are located on the side of the mold body made of mold material 12 opposite the insert 48. These incisions significantly increase the surface area of ​​the mold body made of mold material 12, thus enabling better thermal heat dissipation. In addition to improved heat dissipation through increased surface area, the incisions 64 in the mold material 12, which can be trapezoidal, triangular, rectangular, or semicircular, also improve the contact with the AMB substrate 14. These incisions 64 in the mold material 12 provide space for electrical connections.

[0066] In the illustration according to Figure 4, an adhesive joint 62 is arranged and, opposite it, a schematically depicted clamping joint 63. The mold body made of molding material 12 is held by means of an adhesive joint 62. Alternatively, it is possible to fix it by means of a clamping joint 63.

[0067] Figures 5.1 and 5.2 show various embodiments of fixing the cooling channel 66 below the mold material 12 of the power module 10. Figure 5.1 illustrates that a sheet metal part 78, which delimits the cooling channel 66, can be joined to the mold material, for example, by means of a soldered spring clip, such as a connecting element 77. A seal 78, extending into the plane of the drawing, stretches between the sheet metal part 78 and the underside of the mold material 12 to seal the cavity 68 of the cooling channel 66 against escaping cooling medium 38.

[0068] Figure 5.2 shows that in this embodiment, the connecting element 77 can also be soldered, for example, to the sheet metal part 78 and is hooked onto a shoulder in the mold material 12 of the power module 10. In this case as well, a preload is applied between the sheet metal part 78 and the mold material 12, so that the seal 58 seals the cavity 68 of the cooling channel 66 against escaping cooling medium 38. Figure 5.2 also shows that the insert substrate 14, designed as an insert 48, including the ceramic material 22, is received on the underside of the mold material, preferably partially embedded in it.

[0069] - 10 -

[0070] Figure 6 shows a further embodiment of the power module proposed according to the invention. In this embodiment, a housing 104 of the power module 10 is provided with a number of dome-shaped projections 102. These dome-shaped projections 102, which are preferably formed on the bottom of the housing 104 of the power module 10, serve to receive the mold material 12 in which the insert 78 is embedded. In the embodiment according to Figure 6, the sheet metal part 78, which delimits the cooling channel 66, and a lateral region of the base material 12 are received on a dome-shaped projection 102. The arrangement consisting of the lateral region of the mold material 12 and the sheet metal part 78 can be fastened by a hold-down clamp or a clamping plate 79 on the top of the dome-shaped projection 102 shown schematically here.Thus, the mold material 12 with the insert 48 embedded therein, as well as the cooling channel 66, can be decoupled from the housing 104 of the power module 10. Figure 6 further shows that, in this embodiment, the aforementioned pin-shaped cooling elements 52 project into the cavity 68 of the cooling channel 66 from the underside of the insert 58, and waste heat generated during operation is dissipated via the cooling medium 38, which flows through the cooling channel 66.

[0071] Figures 7.1 and 7.2 show that the cooling channel 66 can also be formed directly in the mold material 12. For this purpose, a cavity 68 is formed in the mold material 12, which can, for example, have a width of 70. The aforementioned pin-shaped cooling elements 52 extend into the cavity 68 in the mold material 12 from the underside of the insert 58. This insert is—shown here only schematically—embedded in the mold material.

[0072] Figure 7.2 shows that a number of housing bodies 76, which can be made of mold material 12, abut each other at butt joints 72 with their opposing end faces 74. The housing bodies 76, in which the cavity 68 shown in Figure 7.1, which serves as a cooling channel 66, is formed, are permeated by the cooling medium 38.

[0073] Figure 8 shows a further embodiment of the power module 10 proposed according to the invention, in which R.415302

[0074] - 11 -

[0075] The insert 48 is also embedded in the mold material 12. The insert 48, formed by the AMB substrate 14 and the pin-shaped cooling elements 72 extending vertically downwards from it, dissipates waste heat into the cooling medium 38 flowing through the cavity 68 of the cooling channel 66.

[0076] As shown in Figure 8, in this embodiment the cooling channel 66 is bounded by the sheet metal part 78. This part, as shown in Figure 8, is provided with corrugated, complementary deformations in which a fixing adhesive 82 and / or a sealing adhesive 84 can be arranged. The fixing adhesive 82 or the sealing adhesive 84 prevents the escape of cooling medium 38 from the cavity 68 of the cooling channel 66. In particular, in this embodiment, the sheet metal part 78 is bonded to the underside of a copper sheet 80, specifically welded to it. The copper sheet 80, in turn, is bonded to the underside of the AMB substrate 14.

[0077] In this embodiment, the sealing and fixing functions are each located laterally away from the cooling channel 66. The sealing and fixing functions are performed by the aforementioned fixing adhesive 82 and / or the aforementioned sealing adhesive 84. Heat is dissipated from the AMB substrate 14 via the pin-shaped cooling elements 52, which extend essentially vertically from its underside into the cooling medium 38.

[0078] Figure 9 shows a further embodiment of the power module 10 proposed according to the invention, in which the insert 48, containing the AMB substrate 14 and the pin-shaped heat sinks 52 extending vertically from it, is embedded. The insert 48 is essentially received on the underside of the mold material 12. As can be seen from Figure 9, in this embodiment the cooling channel 66 is formed, for example, by a brazed aluminum channel 98. The individual, adjacent, and spaced-apart pin-shaped heat sinks 52 protrude through both a spacer material 88 and a perforated sheet 90, which are arranged between the underside of the AMB substrate 14 of the insert 48 on the one hand and the top side of the brazed aluminum sheet 98 on the other.

[0079] - 12 -

[0080] Finally, Figure 10 shows a further embodiment of the power module proposed according to the invention, in which the cooling channel 66 is formed from a plastic tray 96, which is joined to a substantially planar plastic part 100 by one or more hot-joint connections 94. Analogous to the previously described embodiments of the power module proposed according to the invention, the insert 48 is at least partially embedded in the mold material 12. From the underside of the insert 48, the pin-shaped cooling elements 52 extend substantially vertically into the cavity 68 of the cooling channel 66, which in this embodiment is bounded by the plastic tray 96. In this embodiment, sealing is achieved via elastomer seals 92, which can be designed as two-component seals.

[0081] The invention is not limited to the embodiments described here and the aspects highlighted therein. Rather, within the scope specified by the claims, a multitude of modifications are possible that fall within the bounds of what is considered skilled in the art.

Claims

R.415302 - 13 - Claims 1. Power module (10) with an A MB substrate (14) with a cooler (42) through which a cooling medium (38) flows in a flow direction (40), characterized in that a number of pin-shaped cooling elements (52) are formed on an insert (48), which are coated or uncoated and project into the cooling medium (38) flowing through a cooling channel (66).

2. Power module (10) according to claim 1 , characterized in that the pin-shaped heat sinks (52) are additively formed on the insert part (38) by means of a 3D printing process or by bonded wires or by pins attached and joined by material connection, in particular by hard soldering.

3. Power module (10) according to claims 1 and 2, characterized in that the pin-shaped heat sinks (52) are provided with an electroplated nickel plating (54) or with a chemical nickel coating (50).

4. Power module (10) according to claims 1 to 3, characterized in that a mold material (12), sealed via sealing elements (46), is inserted into a mounting opening (44) of the cooler (42).

5. Power module (10) according to claim 4, characterized in that the mold material (12) above the insert part (48) has a number of incisions (64) increasing the surface area of ​​the mold material (12), which are trapezoidal, triangular, rectangular or semicircular in shape.

6. Power module (10) according to claims 1 to 5, characterized in that the cooling medium (38) flows directly around the pin-shaped cooling elements (52) within the cooling channel (66). R.415302 - 14 - 7. Power module (10) according to claims 5 to 6, characterized in that the pin-shaped heat sinks (52) are coated or uncoated and project into a cooling channel (66) which is formed in the mold material (12).

8. Power module (10) according to claim 7, characterized in that the cooling channel (66) is formed by a fixed component (78) which limits the cooling channel (66), which is sealed by at least one seal (58) and is received on the mold material (12) by means of force-fit, form-fit or material-fit connecting elements (77).

9. Power module (10) according to claims 1 to 6, characterized in that the mold material (12) together with the component (78) encompassing it and limiting the cooling channel (66), is received on dome-shaped protrusions (102) in the housing (104) by means of clamping plates or hold-downs (79).

10. Power module (10) according to claims 1 to 6, characterized in that the insert part (48) is embedded in the mold material (12) and the sheet metal part (78) limiting the cooling channel (66) is joined to a copper sheet (80) by means of fixing adhesive (82) and / or sealing adhesive (84).

11. Power module (10) according to claim 10, characterized in that the Cu sheet (80) is joined to one side of the AMB substrate (14) in a materially bonded manner, in particular welded to it.

12. Power module (10) according to claims 10 to 11, characterized in that the fixing adhesive (82) and / or the sealing adhesive (84) is arranged in wave-shaped, mutually complementary deformations in the sheet metal part (78) on the one hand and in the Cu sheet (80) on the other hand.

13. Power module (10) according to claims 1 to 6, characterized in that the cooling channel (66), through which the cooling medium (38) flows, is joined, in particular welded, to a perforated sheet (50) extending below the AM B substrate (14) in a materially bonded manner. R.415302 - 15 - 14. Power module (10) according to claim 13, characterized in that a layer of spacer material (88) runs between the A MB substrate (14) and the perforated sheet (90).

15. Power module (10) according to claims 1 to 6, characterized in that below the AMB substrate (14) of the insert part (48) embedded in the mold material (12) a plastic tray (96) defining the cooling channel (66) is joined to a plastic part (100) via at least one hot-joint connection (94).

16. Use of the power electronics (10) according to any one of claims 1 to 15 in a power electronics or inverter of an electric drive of a passenger vehicle or a commercial vehicle.

Images