Cooling plate, battery separation unit and drive system

Abstract

The invention relates to a cooling plate (10) for cooling at least one component (12), in particular a plurality of components (12), at least one power electronics (14) and for cooling at least one relay (16) of a battery disconnect unit (18) for disconnecting a battery unit (20) from at least one consumer (22) of a drive system (24), comprising a first plate (26), wherein the at least one component (12) can be attached to the first plate (26), a second plate (28), wherein at least one first flow space (30) for a coolant is provided between the first plate (26) and the second plate (28) in order to directly supply coolant to the at least one component (12) of the power electronics (14), and wherein the second plate (28) has at least one mounting rib (32) for mounting at least one relay (16) in order to dissipate heat from the at least one relay (16) via the mounting rib (32) and the second plate (28).

Description

[0001] The invention relates to a cooling plate having the features of independent patent claim 1, a battery separation unit having the features of independent patent claim 7 and a drive system having the features of independent patent claim 10.

[0002] According to the current state of the art, a battery disconnect unit (BDU) is used to switch an electric vehicle's battery on and off depending on the operating state. The three BDU configurations mentioned above are typically used: 1. Fuse and relay 2. Pyro fuse and relay 3. Fuse, pyro fuse and relay

[0003] When using a combination of relays and a circuit using SiC-based semiconductors (AMB components) for a BDU, active cooling of these components is necessary. This can be achieved, for example, with a cooling plate through which a coolant flows. State-of-the-art cooling plates made from aluminum sheets using a brazing process can be used. Depending on the requirements regarding the currents to be switched and thus the heat losses, these cooling plates can be equipped with an additional water fin (internal insert) to increase cooling performance.

[0004] DE 10 2020 206 338 and DE 10 2020 206 339 describe how the cooling of a relay can be achieved via a thermal connection of the busbars in the immediate vicinity of the relay and / or the thermal connection of the relay itself to the battery housing (heat sink).

[0005] DE 11 2015 003 530 describes a heat exchanger composed of a pair of plates.

[0006] When cooling AMB components together with one or more relay modules using a single cold plate, depending on the available space, the problem arises that the two areas to be cooled can negatively influence each other thermally. This means that when cooling the AMB components, the heat flow negatively affects the relay cooling area, and vice versa. This leads to a temperature increase on both the AMB components and the components of the relay module, which has a negative impact on the service life of the components, for example.

[0007] The invention proposes a cooling plate with the features of independent patent claim 1, a battery separation unit with the features of independent patent claim 7, and a drive system with the features of independent patent claim 10. Further features and details of the invention emerge from the subclaims, the description, and the drawings. Features and details described in connection with the cooling plate according to the invention naturally also apply in connection with the battery separation unit according to the invention and / or in connection with the drive system according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.

[0008] A first aspect of the invention is a cooling plate for cooling at least one component, in particular a plurality of components, at least one power electronics unit and for cooling at least one battery separation unit for separating a battery unit from at least one consumer of a drive system, comprising a first plate, wherein the at least one component can be attached to the first plate, a second plate, wherein at least one first flow space for a coolant is provided between the first plate and the second plate in order to flow directly beneath the at least one component of the power electronics, and wherein the second plate has at least one fastening web for fastening at least one relay in order to dissipate heat from the at least one relay via the fastening web and the second plate.

[0009] This cooling plate enables the power electronics to be geometrically and hydraulically thermally decoupled by the component section and the relay cooling area by the relay section. This minimizes the negative effects of interaction between the two areas.

[0010] When coolant flows through the cooling plate, the coolant flows directly beneath the power electronics or at least one component of the power electronics. This is advantageous because a high heat flow must be dissipated over a very small area, whereas the mounting bars absorb the heat from the at least one relay and conduct it to the second plate, where the heat can then be absorbed by the coolant and thus dissipated.

[0011] By providing essentially constant cooling of the power electronics while simultaneously dissipating heat from the relay through the inventive geometry of the cooling plate, the overall temperature of the battery separation unit can be reduced, thereby increasing the service life of the components and thus the safety of the battery separation unit.

[0012] At the same time, the cooling plate enables a reduction in costs, as the reduction in temperature allows cheaper components to be used for the battery separation unit.

[0013] It is particularly advantageous for heat transfer and heat conduction if the first and second plates are made of an aluminum alloy. The first and second plates can be joined together in a fluid-tight manner using a brazing process.

[0014] The battery unit is separated from the load via the power electronics (e.g., SiC MOSFET AMB) and / or the relay. The relay is not part of the battery separation unit. Likewise, the power electronics are part of the battery separation unit. The relay is necessary to meet the requirement for galvanic isolation. The relay separates the positive battery terminal from the load. The power electronics separates the negative battery terminal from the load.

[0015] Within the scope of the invention, it may be advantageous for the at least one flow space to have a coolant distribution area with a coolant inlet and a coolant collection area with a coolant outlet and a first flow area, wherein the first flow area is arranged between the coolant distribution area and the coolant collection area.

[0016] The shape of the coolant distribution area, which is usually V-shaped and widens toward the flow area, ensures that the coolant entering through the coolant inlet is distributed across the entire cross-sectional area, allowing the coolant to flow beneath the base area of ​​the power electronics and dissipate its heat. The reduction in cross-section in the coolant collection area increases the coolant flow velocity, allowing the heated coolant to quickly escape from the flow chamber.

[0017] This ensures in a simple way that the heat generated by the power electronics can be dissipated quickly and effectively.

[0018] Within the scope of the invention, it is conceivable that a flow guide plate is provided with a deflection opening, wherein the flow guide plate is arranged between the first plate and the second plate in the flow space in order to separate a second flow region from the first flow region through the deflection opening, so that the flow of the coolant changes direction, wherein the coolant distribution region is provided between the first plate and the flow guide plate and wherein the coolant collection region is provided between the flow guide plate and the second plate.

[0019] The flow guide plate allows for optimal decoupling of the cooling of the power electronics and the heat dissipation of the relay. The coolant flow in the first flow area initially cools the power electronics. After the flow direction is redirected to the second flow area, the relay can be cooled by the flow over the second plate and the heat conduction via the mounting bars.

[0020] The flow guide plate can also be made of an aluminum alloy and is firmly connected to the first plate and the second plate via a brazing process.

[0021] Within the scope of the invention, it can be provided that the coolant distribution area and the coolant collection area are arranged opposite one another or offset from one another along a longitudinal axis of the cooling plate.

[0022] Opposite means that the coolant inlet of the coolant distribution area and the coolant outlet of the coolant collection area are arranged so that the coolant exits the cooling plate directly after flowing under the power electronics. It is particularly advantageous if either the first plate or the second plate has both the coolant inlet and the coolant outlet.

[0023] With a staggered arrangement of the coolant distribution area and the coolant collection area, the first plate or the second plate is longer in length than the other, with the flow guide plate then serving as a fluid-tight cover for the longer plate. This is particularly advantageous when the coolant inlet and outlet are to be arranged close to one another in order to utilize a limited installation space or to use existing connections. It is particularly advantageous if the flow guide plate has the coolant inlet or outlet so that the connection ports are arranged parallel to one another and in the same direction.

[0024] It is further conceivable that a flow grid is arranged in the flow space between the coolant distribution region and the coolant collection region, in particular in the first flow region between the coolant distribution region and the deflection opening.

[0025] The flow grid can increase turbulence in the flow chamber, thereby increasing heat transfer to the coolant. The flow grid also serves to support the internal pressure created by the coolant.

[0026] The flow grid can be integrally connected to the first plate and / or the second plate or, if present, to the first plate and / or the flow guide plate.

[0027] It is also conceivable that the second plate has a flow structure for influencing the flow of the coolant, that the flow structure has a roughened surface and / or a plurality of elevations.

[0028] Both the roughened surface and the raised portions serve to increase the surface area to optimize heat transfer from the second plate to the cooling fluid. This improves heat dissipation from the second plate and the mounting brackets, allowing optimal heat dissipation of at least one relay.

[0029] Since the first plate and the second plate can be manufactured in a single stamping and / or forming process, there are no limits to the shapes of the raised portions of the second plate. For example, the raised portions can be cross-shaped, dome-shaped, and / or rib-shaped.

[0030] A second aspect of the invention is a battery separation unit for separating a battery unit from at least one consumer, with a cooling plate according to the first aspect of the invention, with at least one ceramic substrate, with at least one component of at least one power electronics system, wherein the at least one ceramic substrate is arranged on an outer side of the first plate, wherein the at least one flow space is arranged below the at least one component of the power electronics, and with at least one relay, wherein the relay is arranged via at least one busbar on the at least one fastening web of the second plate.

[0031] For the thermal and mechanical connection of at least one power electronics component, a cold-sprayed copper layer can be applied to the first plate of the cooling plate. The underside of the at least one component, which comprises a copper alloy, is then bonded to the copper layer on the cooling plate in a further soldering process. This achieves a very good thermal transition from the at least one power electronics component to the cooling plate and thus to the coolant.

[0032] The at least one relay can be arranged directly on the at least one mounting bracket, with the electrical connection being implemented via a busbar arranged between the at least one relay and the mounting bracket. It is also conceivable for the at least one relay to be arranged on a busbar, and for the busbar to position the at least one relay on the mounting bracket.

[0033] To dissipate heat from the at least one relay, a heat-conducting medium can be provided between the busbar and the at least one mounting bar for thermal contact with the second plate. This increases the heat transfer between the busbar and the mounting bar. The heat dissipation from the mounting bar into the cooling fluid is primarily influenced by the material thickness of the second plate.

[0034] Within the scope of the invention, it is optionally possible for each power electronics unit to be assigned a relay.

[0035] Several areas can be provided on the cooling plate, each for a power electronics unit and its relay in the at least one component. It is advantageous if each power electronics unit is assigned its own relay, thus ensuring the proper functioning of the battery separation unit.

[0036] It is conceivable that at least one mounting bracket, preferably two mounting brackets, are provided on the second plate for each relay. These can be arranged on one side or on opposite sides of the second plate.

[0037] Furthermore, it can be provided within the scope of the invention that a relay is arranged on two fastening webs via a busbar, in particular two busbars.

[0038] This allows the relay's weight to be distributed more effectively, reducing the locally generated bending moment. At the same time, the heat generated in the relay can be conducted to the second plate via two mounting elements, allowing it to be dissipated more quickly.

[0039] A third aspect of the invention is a drive system having a battery unit, a consumer, and a battery separation unit according to the second aspect of the invention, wherein the battery unit and the battery separation unit are electronically connected to one another via a battery interface of the battery separation unit, and wherein the consumer and the battery separation unit are connected to one another via a consumer interface of the battery separation unit.

[0040] Advantages described in detail for the cooling plate according to the first aspect of the invention apply equally to the battery separation unit according to the second aspect of the invention and the drive system according to the third aspect of the invention.

[0041] The drive system includes the battery separation unit described above and its advantages.

[0042] Further advantages, features, and details of the invention will become apparent from the following description, which describes several embodiments of the invention in detail with reference to the drawings. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination. The invention is illustrated in the following figures: Fig. 1 isometric representation of a cooling plate according to the invention, Fig. 2 a sectional view of a cooling plate according to the invention, Fig. 3 a schematic representation of a battery separation unit according to the invention, Fig. 4 a schematic representation of a drive system according to the invention.

[0043] In the Fig. 1 and Fig. 2 shows a cooling plate 10 for cooling at least one component 12, in particular a plurality of components 12, at least one power electronics unit 14 and for cooling at least one relay 16 of a battery separation unit 18 for separating a battery unit 20 from at least one consumer 22 of a drive system 24. Fig. 2 a sectional view of the cooling plate 10 of the Fig. 1 shown.

[0044] The cooling plate 10 of the Fig. 1 and Fig. 2 has a first plate 26 and a second plate 28. At least one component 12 for the subsequent battery separation unit 18 can be attached to the first plate 26. As shown in the Fig. As can be seen in Figure 2, at least one first flow chamber 30 for a coolant is provided between the first plate 26 and the second plate 28, in order to flow directly beneath the at least one component 12 of the power electronics 14. In addition, the second plate 28 has at least one mounting web 32 for mounting at least one relay 16, in order to dissipate heat from the at least one relay 16 via the mounting web 32 and the second plate 28.

[0045] In order to be able to optimally design the flow in the flow space 30, the at least one flow space 30 has a coolant distribution region 34 with a coolant inlet 36 and a coolant collection region 38 with a coolant outlet 40 and a first flow region 42, wherein the first flow region 42 is arranged between the coolant distribution region 34 and the coolant collection region 38.

[0046] Additionally, a flow guide plate 44 with a deflection opening 46 is provided. This flow guide plate 44 is arranged between the first plate 26 and the second plate 28 in the flow chamber 30 and is integrally connected to both the first plate 26 and the second plate 28 at a connecting edge, for example, via a soldered connection.

[0047] The deflection opening 46 serves to separate a second flow region 48 from the first flow region 42, so that the flow of the coolant changes direction. By deflecting the flow in the flow chamber 30, the flow path is positively extended. The flow first flows through the first flow region 42, cooling the power electronics 14. The flow is then deflected to flow through the second flow region 48, absorbing the heat from the second plate 28, thereby cooling the relays 16. The flow guide plate 44 thus thermally decouples the cooling of the power electronics 14 from the cooling of the relay 16.

[0048] In this embodiment, the coolant distribution region 34 is provided between the first plate 26 and the flow guide plate 44 and the coolant collection region 38 is provided between the flow guide plate 44 and the second plate 28.

[0049] The coolant distribution region 34 and the coolant collection region 38 are arranged offset from one another along a longitudinal axis L of the cooling plate 10. The coolant inlet 36 and the coolant outlet 40 are thus arranged essentially next to one another, so that the lines to be connected can also be arranged next to one another, thus reducing the installation space. For this purpose, the second plate 28 is longer in its longitudinal extent than the first plate 26, and the second flow region 48 and the coolant collection region 38 are sealed in a fluid-tight manner by the flow guide plate 44. The coolant inlet 36 is provided on the first plate 26, with the coolant outlet 40 being provided on the flow guide plate 44 to ensure that the installation direction of the coolant inlet 36 and the coolant outlet 40 is the same.

[0050] In order to increase the surface area for the flow and to generate turbulence of the flow for improved heat transfer, a flow grid 50 is arranged in the flow space 30 between the coolant distribution area 34 and the coolant collection area 38, in particular in the first flow area 42 between the coolant distribution area 34 and the deflection opening 46.

[0051] For optimal cooling of the at least one relay 16 via the at least one mounting web 32 and the second plate 28, the second plate 28 has a flow structure 52 for influencing the flow of the coolant, wherein the flow structure 52 has a plurality of elevations. As shown in Fig. As can be seen in Figure 2, the elevations are dome-shaped. It would be conceivable to use a roughened surface additionally or alternatively to increase the surface area exposed to the airflow.

[0052] In Fig. 3 shows a battery separator unit 18 for separating a battery unit 20 from at least one consumer 22. The battery separator unit 18 has a cooling plate 10 according to one of the Fig. 1 or Fig. 2, at least one ceramic substrate 54, and at least one component 12 of at least one power electronics unit 14 and a relay 16. The at least one ceramic substrate 54 is arranged on an outer side 56 of the first plate 26. The at least one flow chamber 30, in particular the first flow region 42, is arranged below the at least one component 12 of the power electronics unit 14. The relay 16 is arranged via at least one busbar 58 on the at least one fastening web 32 of the second plate 28. As in Fig. As shown in Figure 3, the relay 16 is arranged via two busbars 58, each on a mounting bracket 32. The relay 16 is thus arranged between two mounting brackets 32 and is supported and cooled via a busbar 58 on each mounting bracket 32.

[0053] In the illustrated embodiment, only one relay 16 is shown. However, it is conceivable that multiple power electronics 14 are provided, with each power electronics 14 being assigned a relay 16. These can then be arranged opposite one another on the cooling plate 10, in which case additional mounting webs 32 are provided on the second plate 28.

[0054] In Fig. 4 is a drive system 24 with a battery unit 20, a consumer 22 and a battery separation unit 18 according to the Fig.3. The battery unit 20 and the battery separation unit 18 are electronically connected to each other via a battery interface 60 of the battery separation unit 18. The load 22 and the battery separation unit 18 are connected to each other via a load interface 62 of the battery separation unit 18. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2020 206 338

[0004] DE 10 2020 206 339

[0004] DE 11 2015 003 530

[0005]

Claims

[1] Cooling plate (10) for cooling at least one component (12), in particular a plurality of components (12), at least one power electronics unit (14) and for cooling at least one relay (16) of a battery separation unit (18) for separating a battery unit (20) from at least one consumer (22) of a drive system (24), comprising a first plate (26), wherein the at least one component (12) can be attached to the first plate (26), a second plate (28), wherein at least one first flow space (30) for a coolant is provided between the first plate (26) and the second plate (28) in order to flow directly beneath the at least one component (12) of the power electronics (14), and wherein the second plate (28) has at least one fastening web (32) for fastening at least one relay (16) in order to dissipate heat from the at least one relay (16) via the fastening web (32) and the second plate (28). [2] Cooling plate (10) according to claim 1, characterized by in that the at least one flow space (30) has a coolant distribution region (34) with a coolant inlet (36) and a coolant collection region (38) with a coolant outlet (40) and a first flow region (42), wherein the first flow region (42) is arranged between the coolant distribution region (34) and the coolant collection region (38). [3] Cooling plate (10) according to claim 1 or 2, characterized bythat a flow guide plate (44) with a deflection opening (46) is provided, wherein the flow guide plate (44) is arranged between the first plate (26) and the second plate (28) in the flow space (30) in order to separate a second flow region (48) from the first flow region (42) through the deflection opening (46), so that the flow of the coolant changes direction, wherein the coolant distribution region (34) is provided between the first plate (26) and the flow guide plate (44) and wherein the coolant collection region (38) is provided between the flow guide plate (44) and the second plate (28). [4] Cooling plate (10) according to claim 3, characterized by that the coolant distribution region (34) and the coolant collection region (38) are arranged opposite one another or offset from one another along a longitudinal axis (L) of the cooling plate (10). [5] Cooling plate (10) according to one of the preceding claims, characterized bythat a flow grid (50) is arranged in the flow space (30) between the coolant distribution region (34) and the coolant collection region (38), in particular in the first flow region (42) between the coolant distribution region (34) and the deflection opening (46). [6] Cooling plate (10) according to one of the preceding claims, characterized by that the second plate (28) has a flow structure (52) for influencing the flow of the coolant, that the flow structure (52) has a roughened surface and / or a plurality of elevations. [7] Battery separation unit (18) for separating a battery unit (20) from at least one consumer (22), with a cooling plate (10) according to one of the preceding claims, with at least one ceramic substrate (54), with at least one component (12) of at least one power electronics unit (14), wherein the at least one ceramic substrate (54) is arranged on an outer side (56) of the first plate (26), wherein the at least one flow space (30) is arranged below the at least one component (12) of the power electronics unit (14), and with at least one relay (16), wherein the relay (16) is arranged via at least one busbar (58) on the at least one fastening web (32) of the second plate (28). [8] Battery separator unit (18) according to claim 7, characterized by that each power electronics unit (14) is assigned a relay (16). [9] Battery separator unit (18) according to one of claims 7 or 8, characterized bythat a relay (16) is arranged on two fastening webs (32) via a busbar (58), in particular two busbars (58). [10] Drive system (24) with a battery unit (20), a consumer (22) and a battery separation unit (18) according to one of claims 7 to 9, wherein the battery unit (20) and the battery separation unit (18) are electronically connected to one another via a battery interface (60) of the battery separation unit (18) and wherein the consumer (22) and the battery separation unit (18) are connected to one another via a consumer interface (62) of the battery separation unit (18).

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