Battery disconnection unit and drive system

Abstract

The invention relates to a battery disconnecting unit (10) for disconnecting a battery device (12) from at least one load (14) of a drive system (16), comprising: a cooling device (18) having a cooling channel (20) for passing a dielectric fluid from a cooling channel inlet (22) to a cooling channel outlet (24) of the cooling channel (20), wherein the cooling channel (20) has a base plate (26); at least one component (28), in particular a plurality of components (28), of the power electronic component (30), wherein the at least one component (28) of the power electronic component (30) in the cooling channel (20) is arranged on at least one ceramic substrate (32) on a substrate (26) of the cooling device (18) in order to be overflowed by a dielectric fluid.

Description

Technical Field

[0001] The invention relates to a battery disconnect unit having the features of independent claim 1 and to a drive system having the features of independent claim 14 . Background Art

[0002] According to the prior art, a battery disconnect unit (Battery Disconnect Unit-BDU) is used to connect and disconnect the battery of an electric vehicle according to the operating state. Here, three BDU configuration schemes are usually used:

[0003] 1. Fuse devices and relays

[0004] 2. Thermoelectric fuses and relays

[0005] 3. Fuse devices, thermoelectric fuses and relays.

[0006] When a combination of relays and circuits implemented by SiC-based semiconductors is used on AMB components for BDUs, active cooling of these components is required because these semiconductors reach higher heat fluxes and at the same time higher temperatures due to their compact design. The AMB stands for Active Metal Brazing, and the component is a ceramic substrate that is directly materially connected to a substrate, such as a cooling plate, by a welded connection. For example, cooling is achieved using a cooling plate through which a coolant flows. Here, according to the prior art, cooling plates made of aluminum sheets in a brazing process can be used. Depending on the requirements related to the current to be switched and the power loss in the form of heat, these cooling plates can be equipped with additional water sheets (internal inserts) to improve the cooling performance. In this case, the AMB component is welded to the cooling plate to achieve optimal heat transfer from the AMB component to the cooling plate via the water sheets entering the cooling fluid.

[0007] Here, high demands are placed not only on the selection of the internal inserts, but also on the volume flow of the cooling fluid and its maximum permissible temperature. The goal is to cool the semiconductors effectively and to ensure that the temperature distribution of the individual chips relative to one another is as uniform as possible.

[0008] These requirements lead to the use of cooling plates with relatively high pressure losses in such cooling concepts. This, combined with the required high volume flows, leads to additional cooling systems with high pumping power. This not only consumes a lot of energy but also leads to high costs and weight for the vehicle due to its size.

[0009] Chips are usually cast to prevent leakage currents and short circuits in conductor paths that run close to each other and in parallel. Additional components, such as a limiting frame and a casting compound, are required, which results in additional costs. Summary of the invention

[0010] The aforementioned problem is solved by a battery disconnect unit having the features of independent claim 1 and a drive system having the features of independent claim 14. Further features and details of the invention are derived from the dependent claims, the description and the drawings. Features and details described here with respect to the battery disconnect unit according to the invention naturally also apply to the drive system according to the invention and vice versa, so that the disclosure with respect to the various aspects of the invention always refers to each other or can refer to each other.

[0011] A first aspect of the present invention is a battery disconnect unit, which is used to disconnect a battery device from at least one load of a drive system, and the battery disconnect unit has: a cooling device, the cooling device having a cooling channel, the cooling channel being used to allow a dielectric fluid to flow from a cooling channel inlet to a cooling channel outlet of the cooling channel, wherein the cooling channel has a substrate; and at least one component of a power electronic device, in particular a plurality of components, wherein at least one component of the power electronic device in the cooling channel is arranged on at least one ceramic substrate on the substrate of the cooling device in order to allow the dielectric fluid to flow through.

[0012] At least one component of a power electronic device, such as a SiC chip, is arranged on at least one ceramic substrate. In this case, multiple components can also be arranged on the ceramic substrate. It is also conceivable to provide multiple ceramic substrates, each of which has at least one component or multiple components.

[0013] In this case, the cooling device can be connected to a closed cooling circuit, so that the dielectric fluid can be introduced through a cooling channel inlet of the cooling circuit and can be discharged through a cooling channel outlet.

[0014] Flooding the components or at least one component of the power electronics is particularly advantageous, since the at least one component of the power electronics generates a high heat flux for a very small space, which has to be discharged.

[0015] The heat partially enters the base plate through the ceramic substrate and is then exported outwards. However, most of the heat is exported along with the dielectric by flowing into the components of the power electronic device. Due to directly flowing into at least one component of the power electronic device, no additional thermal resistance will be generated as in the prior art. On the contrary, a smaller temperature difference is generated between the heat source and the dielectric fluid. The generated heat is uniformly and efficiently exported by overflow, so that the components of the power electronic device or at least one component can be quickly and easily cooled.

[0016] Here, the cooling channel inlet through which the dielectric fluid enters is arranged spaced apart from the region of at least one component of the power electronic device relative to the flow direction so as to form sufficient flow development for overflow. Here, the cooling channel outlet is arranged spaced apart from the region of at least one component of the power electronic device in the flow direction.

[0017] It can be advantageous within the scope of the invention if the cooling device has a cooling plate which is arranged opposite the base plate.

[0018] Here, the cooling plate is arranged opposite to the base plate, in particular geometrically opposite to each other, wherein they are arranged spaced apart from each other. In order to form the flow channel, at least two opposite side walls are provided, which are arranged between the cooling plate and the base plate.

[0019] When the flow flows through the base plate and the cooling plate of the cooling device of the battery disconnect unit, on the one hand, the heat of at least one component of the power electronic device is dissipated and cooled at the same time, so that the dielectric always has a constant temperature, so that the necessary temperature gradient exists for dissipating the heat flux density of at least one component of the power electronic device.

[0020] It is conceivable within the scope of the invention that a flow structure is provided in the cooling channel of the cooling device for deflecting the flow of the dielectric fluid, wherein the flow structure is designed to deflect the flow of the dielectric fluid directly to at least one component of the power electronics.

[0021] On the one hand, flow deflection and guided can be made by flow structure, so that most of the flow is directly deflected towards at least one component or a plurality of components of power electronic devices. At the same time, the turbulence of flow can be increased by flow structure. The increase of turbulence or the regular separation of boundary layer makes it keep turbulence, thereby realizes efficient heat extraction. In addition, by flow structure, not only can flow be produced and guided to components, but also can introduce extra turbulence to improve the lateral exchange of heat or dielectric fluid in the flow. In this case, different geometric shapes can be used for flow structure.

[0022] It can be provided within the scope of the invention that the flow structure can be connected to the cooling plate and / or to at least two side walls of a cooling channel of the cooling device and / or that the flow structure can be integrated into the cooling plate or that the flow structure is integral with the cooling plate.

[0023] The flow structure can be a separate new component for insertion, which can be easily connected to the cooling plate or at least two side walls of the battery disconnect unit. It is conceivable that the flow structure can be welded, glued, screwed or clamped in this case.

[0024] It is also conceivable that they are formed integrally, ie the flow structure of the cooling device and the cooling plate and / or at least two side walls of the cooling channel are designed such that the flow structure can be easily installed therein, for example by placing or inserting it.

[0025] The connection to the cooling plate and / or the side wall and the integration therein can be easily realized and at the same time can be designed flexibly. In these embodiments, it is conceivable to replace the flow structure. Thus, in this case, the arrangement of the components on the ceramic substrate can be changed, since the flow structure can also be adjusted or replaced accordingly.

[0026] At the same time, it is conceivable that the cooling plate and the flow structure are formed in one piece, wherein the cooling plate is then provided with an outer structure of the flow structure for deflecting the flow.

[0027] A cooling plate which is produced in one piece, ie with the flow structure, can be easily produced and handled.

[0028] Furthermore, it is conceivable that the flow structure is designed to be wavy or zigzag-shaped.

[0029] These shapes have proven to be particularly advantageous for deflecting the flow and generating lateral flows.

[0030] Furthermore, it is conceivable that the flow structures are webs, wherein the webs are arranged in the cooling channels in order to separate the cooling channels and to deflect the flow of the dielectric fluid.

[0031] For this reason, between substrate and cooling plate, be additionally arranged with the third side wall, wherein the third side wall is arranged orthogonally with at least two side walls (not shown). Spacer and the third side wall are arranged and form deflection area spaced apart from each other, so that the dielectric as dielectric fluid enters cooling channel entrance as deflow between substrate and the partition board and flows to power electronic device in parallel arrangement mode, so that this power electronic device is cooled uniformly with identical fluid temperature.Then, the flowing dielectric deflects 180 ° in deflection area, and flows to cooling channel outlet as the reflux between partition board and cooling plate.Here, deflow and reflux are parallel to each other and flow countercurrently to each other.

[0032] It is also conceivable that at least one ceramic substrate has a recess, so that at least one secondary cooling channel is provided below at least one component of the power electronics arranged thereon.

[0033] The secondary cooling channels are formed so that the components of the power electronics or at least one component is flushed from below. It is also conceivable that there are a plurality of recesses below at least one component, so that a plurality of secondary cooling channels are formed.

[0034] A very high heat flux is particularly advantageous, since the heat can be dissipated quickly and easily both from the top side of the at least one component and from the bottom side of the at least one component.

[0035] Furthermore, it can be provided within the scope of the invention that the cooling plate has at least two, preferably a plurality of cooling fins on an inner surface facing the cooling channel and / or on an outer surface facing away from the cooling channel.

[0036] By means of cooling fins on the inner surface facing the cooling channel or on the outer surface facing away from the cooling channel, an additional surface area increase can be produced, by which heat can be dissipated. At the same time, it is conceivable that the cooling plate additionally cools the outer surface with at least two cooling fins in order to cool the dielectric so that as much heat as possible can be dissipated from the components of the power electronics.

[0037] In connection with the invention, it is conceivable that the cooling plate can be connected to a cooling unit of the load or of the battery arrangement or can be provided with air cooling and / or liquid cooling.

[0038] As already explained above, the cooling device is a closed cooling circuit. Here, the cooling circuit can be connected to the cooling unit of the load or the battery device, so that no additional cooling circuit is required here. This is particularly efficient and cost-effective.

[0039] However, it is also conceivable to provide a liquid cooler which is an additional cooling unit in which the cooling device is integrated.

[0040] It is conceivable within the scope of the invention that the cooling device can be connected to an external cooling unit.

[0041] The cooling unit can be a heat exchanger. A closed circuit for the dielectric fluid is provided in order to cool the dielectric fluid in the cooling unit.

[0042] Furthermore, it is conceivable for the base plate and / or the cooling plate to consist of a heat-conducting material, in particular aluminum.

[0043] The use of a thermally conductive material, in particular aluminum, is particularly advantageous, since the heat can already be partially dissipated via the base or the substrate.

[0044] Within the scope of the invention, a copper layer, in particular a cold-sprayed copper layer, can optionally be arranged between the base plate and the ceramic substrate.

[0045] The use of a copper layer to connect the ceramic substrate to the base plate is particularly advantageous, since not only a thermal connection but also a mechanical connection can be achieved quickly and efficiently. In this case, the ceramic substrate together with at least one component is connected to the copper layer on the base plate in a material-locking manner by means of a soldering process. This allows very good heat transfer from the ceramic substrate to the base plate.

[0046] It can be advantageous within the scope of the invention if the dielectric fluid has a viscosity of 0.5 mPas to 1000 mPas, preferably 0.5 mPas to 100 mPas.

[0047] Dielectric fluid is a non-conductive fluid. Dielectric fluid can also have the viscosity of the increase in the scope between 1mPas to 1000mPas. In this case, viscosity can change temporarily due to the dielectric fluid heating. Simultaneously, it should be ensured that there is a certain viscosity, so that uniform flow can be produced. At this, dielectric fluid preferably has a viscosity of 0.5-100mPas, because they can ensure uniform flow and well absorb heat flux.

[0048] It is conceivable within the scope of the present invention that the dielectric fluid has a heat capacity of 0.8 to 4 kJ / kgK, preferably 1.0 to 2.5 kJ / kgK.

[0049] Dielectric fluids with increased heat capacity are able to absorb and dissipate more heat. Thus, dielectric fluids with a heat capacity of 1.0 to 2.5 kJ / kgK ensure that the generated heat is dissipated quickly and efficiently.

[0050] Within the scope of the invention, a battery interface for electrical connection to a battery device and a load interface for electrical connection to a load may be provided.

[0051] The battery interface and the load interface are particularly conducive to a simple connection with a battery unit or a load of a drive system. Here, these load interfaces or battery interfaces can be arranged to control and regulate the battery disconnect unit or the battery unit and the load by the battery disconnect unit. However, it is also conceivable that specific data such as the temperature or flow of the dielectric fluid is transmitted to the load interface or the battery interface of the data communication of the control unit.

[0052] A second aspect of the present invention is a drive system according to the present invention, which has a battery device, a load and a battery disconnect unit according to the first aspect of the present invention, wherein the battery device and the battery disconnect unit are electronically connected to each other via a battery interface, and wherein the load and the battery disconnect unit are electronically connected to each other via a load interface.

[0053] The drive system includes the battery disconnect unit described above and its advantages.

[0054] The advantages described in detail for the battery disconnect unit according to the first aspect of the invention also apply to the drive system according to the second aspect of the invention, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Further advantages, features and details of the invention are apparent from the following description, in which a number of exemplary embodiments of the invention are described in detail with reference to the accompanying drawings. The features mentioned in the claims and the description can form the subject matter of the invention individually or in any combination. The invention is illustrated in the following figures:

[0056] Figure 1 A schematic diagram showing a first embodiment of a battery disconnect unit according to the present invention is shown;

[0057] Figure 2 A schematic diagram showing a second embodiment of a battery disconnect unit according to the present invention;

[0058] Figure 3 A schematic diagram showing a third embodiment of a battery disconnect unit according to the present invention;

[0059] Figure 4 A schematic diagram of a drive system according to the present invention is shown. DETAILED DESCRIPTION

[0060] Figure 1 , Figure 2 and Figure 3 1 and 2 show a battery disconnect unit 10 for disconnecting a battery device 12 from at least one load 14 of a drive system 16. The battery disconnect unit has a cooling device 18 and at least one component 28 of a power electronic device 30, wherein the cooling device has a cooling channel 20 for allowing a dielectric fluid to flow from a cooling channel inlet 22 of the cooling channel 20 to a cooling channel outlet 24.

[0061] In this case, the cooling channel 20 has a base plate 26 and a cooling plate 34 which is arranged opposite the base plate 26 .

[0062] In this case, at least one component 28 of the power electronics 30 in the cooling channel 20 is arranged on at least one ceramic substrate 32 on the base plate 26 of the cooling device 18 in order to allow a dielectric fluid to flow through it.

[0063] according to Figure 1 In the first embodiment, a flow structure 36 is provided in the cooling channel 20 of the cooling device 18, and the flow structure is used to deflect the flow of the dielectric fluid, such as Figure 1The flow structure 36 is zigzag-shaped and is designed and arranged above at least one component of the power electronics so as to deflect the flow of the dielectric fluid so as to flow directly onto at least one component 28 of the power electronics 30 .

[0064] In this case, the flow structure 36 is connected to at least two side walls 38 of the cooling channel 20 of the cooling device 18 .

[0065] It is also conceivable that the flow structure can be connected to the cooling plate 34. The flow structure 36 can be integrated into the cooling plate 34 or can be produced in one piece with the cooling plate 34.

[0066] Figure 1 The cooling plate is connected to a liquid cooling device and flows on the outer surface 48 facing away from the cooling channel 20. A connection with an air cooling device is also conceivable here. In order to increase the surface area for cooling or for dissipating heat from the cooling channel 20, at least two cooling fins 50 are arranged on the outer surface 48. It is also conceivable to arrange the cooling fins 50 on the inner side.

[0067] The cooling fins can be arranged continuously along the flow direction or, as shown in the figure, interruptedly along the outer surface. Here, a plurality of fins can also be arranged parallel to each other.

[0068] In accordance with Figure 2 In the battery disconnect unit of the embodiment of the present invention, at least one ceramic substrate 32 has a recess 40 , so that at least one secondary cooling channel 42 is provided below at least one component 28 of the power electronic device 30 arranged thereon.

[0069] In the present case, such a recess 40 is provided below each component 28 of the power electronics 30 .

[0070] exist Figure 3 In FIG. 3 , the flow structure 36 is a partition 60 , wherein the partition 60 is arranged in the cooling channel 20 in order to divide the cooling channel 20 and deflect the flow of the dielectric fluid.

[0071] For this reason, between substrate 26 and cooling plate 34, a third side wall 38 is additionally arranged, wherein the third side wall 38 is arranged to be orthogonal to at least two side walls (not shown). Divider 60 and the third side wall 38 are arranged spaced apart from each other and form a deflection region 62, so that the dielectric as a dielectric fluid enters at cooling channel inlet 22 as a deflow 64 between substrate 26 and separator 60 and flows through the power electronic device 30 arranged in parallel, so as to cool it uniformly with the same fluid temperature. Then, the flowing dielectric deflects 180 ° in deflection region 62 and flows to cooling channel outlet 24 as a return flow 66 between separator 60 and cooling plate 34. Here, the deflow 64 and the return flow 66 flow in parallel and countercurrent to each other.

[0072] exist Figure 1 as well as Figure 2 and Figure 3 In the embodiment of, base plate 26 and cooling plate 34 are all made of heat conducting material, here made of aluminum. Here, in order to mount ceramic substrate 32 on the base plate, a copper layer 44, especially a cold sprayed copper layer 44, is provided, which is used to weld the ceramic substrate on the base plate.

[0073] The dielectric fluid used here has a viscosity of 0.5 mPas 20° C. to 1000 mPas 20° C. and a heat capacity of 0.8 to 4 kJ / kgK.

[0074] Furthermore, in both exemplary embodiments, a battery interface 56 for electrical connection to the battery device 12 and a load interface 58 for electrical connection to the load 14 are provided.

[0075] Figure 4 The drive system 16 is shown in FIG. Figure 1 or Figure 2 The battery device 12, the load 14 and the battery disconnect unit 10. Here, the battery device 12 and the battery disconnect unit 10 are electrically connected to each other via a battery interface 56, and the load 14 and the battery disconnect unit 10 are electrically connected to each other via a load interface 58.

Claims

1. A battery disconnect unit (10) for disconnecting a battery device (12) from at least one load (14) of a drive system (16), the battery disconnect unit comprising: A cooling device (18), the cooling device having a cooling channel (20), the cooling channel being used to allow a dielectric fluid to flow from a cooling channel inlet (22) of the cooling channel (20) to a cooling channel outlet (24), wherein the cooling channel (20) has a base plate (26); at least one component (28), in particular a plurality of components (28), of a power electronic device (30), At least one component (28) of the power electronic device (30) in the cooling channel (20) is arranged on at least one ceramic substrate (32) on the base plate (26) of the cooling device (18) for the dielectric fluid to flow through.

2. The battery disconnect unit (10) according to claim 1, It is characterized in that The cooling device (18) has a cooling plate (34) arranged opposite to the base plate (26).

3. The battery disconnect unit (10) according to claim 1 or 2, It is characterized in that A flow structure (36) is provided in a cooling channel (20) of the cooling device (18), the flow structure being used to deflect the flow of a dielectric fluid, wherein the flow structure (36) is designed to deflect the flow of the dielectric fluid so that the flow directly flows toward at least one component (28) of the power electronic device (30).

4. The battery disconnect unit (10) according to claim 3, It is characterized in that The flow structure (36) can be connected to the cooling plate (34) and / or at least two side walls (38) of a cooling channel (20) of the cooling device (18), and / or The flow structure (36) can be integrated into the cooling plate (34), or The flow structure (36) and the cooling plate (34) are integrated.

5. The battery disconnect unit (10) according to claim 3 or 4, It is characterized in that The flow structure (36) is configured in a wave shape or a zigzag shape.

6. A battery disconnect unit (10) according to any one of the preceding claims, It is characterized in that The at least one ceramic substrate (32) has a recess (40) such that at least one secondary cooling channel (42) is provided below at least one component (28) of the power electronic device (30) arranged thereon.

7. A battery disconnect unit (10) according to any one of the preceding claims, It is characterized in that The cooling plate (34) has at least two, preferably a plurality of cooling fins (50) on an inner surface (46) facing the cooling channel (20) and / or an outer surface (48) facing away from the cooling channel (20).

8. A battery disconnect unit (10) according to any one of the preceding claims, It is characterized in that The cooling plate (34) can be connected to a cooling unit (52) of the load (14) or of a battery or can be provided with an air or liquid cooling device (54).

9. A battery disconnect unit (10) according to any one of the preceding claims, It is characterized in that The base plate (26) and / or the cooling plate (34) are made of a heat-conducting material, in particular aluminum.

10. The battery disconnect unit (10) according to any one of the preceding claims, It is characterized in that A copper layer (44), in particular a cold-sprayed copper layer (44), is arranged between the base plate (26) and the ceramic substrate (32).

11. The battery disconnect unit (10) according to any one of the preceding claims, It is characterized in that The dielectric fluid has a viscosity of 0.5 mPas (20° C.) to 1000 mPas (20° C.), preferably 0.5 mPas (20° C.) to 100 mPas (20° C.).

12. The battery disconnect unit (10) according to any one of the preceding claims, It is characterized in that The dielectric fluid has a heat capacity of 0.8 to 4 kJ / kgK, preferably 1.0 to 2.5 kJ / kgK.

13. The battery disconnect unit (10) according to any one of the preceding claims, It is characterized in that A battery interface (56) for electrically connecting to the battery device (12) and a load interface (58) for electrically connecting to the load (14) are provided.

14. A drive system (16) comprising a battery device (12), a load (14) and a battery disconnect unit (10) according to any of the preceding claims, wherein the battery device (12) and the battery disconnect unit (10) are electronically connected to each other via a battery interface (56), and wherein the load (14) and the battery disconnect unit (10) are electronically connected to each other via a load interface (58).

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