Drive assembly for a motor vehicle

Abstract

The invention relates to a drive assembly (1) for a motor vehicle (10). The drive assembly (1) comprises a first drive unit (2), which has first power electronics (2.1) and a first electric machine (2.2), a second drive unit (3), which has second power electronics (3.1) and a second electric machine (3.2), and a cooling circuit (4) for cooling the first drive unit (2) and the second drive unit (3) by means of a cooling liquid that can be conducted in the cooling circuit (4). The first power electronics (2.1) and the second power electronics (3.1) are provided upstream of the first electric machine (2.2) and the second electric machine (3.2) in the cooling circuit (4). The first drive unit (2) has a first housing (2.3) in which the first power electronics (2.1) and the first electric machine (2.2) are provided, and the second drive unit (3) has a second housing (3.3) in which the second power electronics (3.1) and the second electric machine (3.2) are provided.

Description

[0001] DRIVE ARRANGEMENT FOR A MOTOR VEHICLE

[0002] The present disclosure relates to a drive arrangement for a motor vehicle, and / or a motor vehicle comprising the drive arrangement.

[0003] In the cooling systems of electrically powered vehicles, such as battery electric vehicles (BEVs), the drive units are typically each considered a single unit. An inverter, an electric motor, and other components are intelligently cooled internally using a cooling fluid, but the entire unit is integrated into the vehicle's cooling system as a single unit. This integration can occur either in parallel or in series when multiple drive units are used in a vehicle. Other elements requiring liquid cooling are also integrated into the cooling system and positioned before, after, or next to the drive units.

[0004] Inverters require significantly lower flow temperatures than electric motors. Inverters add significantly less heat to the cooling system than electric motors.

[0005] When multiple drive units are connected in parallel, all drive units receive the same flow temperature, but the fluid volume to be circulated adds up, resulting in high flow rates in all areas of the cooling system where the flows are combined, such as valve blocks, heat exchangers, and air-to-water coolers. This results in very high pump performance and high outlet temperatures from the air-to-water coolers, for example.

[0006] When multiple drive units are connected in series, the second unit experiences a significantly higher flow temperature, as the waste heat from the first unit has already heated the coolant. This flow temperature is limited by the maximum flow temperature of the second unit's inverter. This places extreme demands on the air-water cooler, for example.DE 10 2022 132 659 A1 describes a cooling system for a vehicle driven by wheel hub electric motors, comprising a cooling water channel provided in a wheel hub electric motor mounted on a wheel of a vehicle so that cooling water for cooling the wheel hub electric motor can pass through the cooling water channel, a cooling water channel provided in an inverter for driving and controlling the wheel hub electric motor so that cooling water for cooling the inverter can pass through the cooling water channel, a radiator provided to dissipate heat of the cooling water that has cooled the wheel hub electric motor and the inverter, and a cooling water circulation line connected such that the cooling water can circulate between the cooling water channel of the wheel hub electric motor, the cooling water channel of the inverter, and the radiator.

[0007] US 2023 / 0226885 A1 describes a thermal control system for an electric vehicle, including a powertrain thermal architecture, a cabin heating arrangement, a battery thermal architecture, and a cabin cooling arrangement.

[0008] DE 10 2022 206 296 A1 describes a cooling system for a vehicle, comprising an engine cooling component for cooling an electric motor of the vehicle, a cooling element for cooling an inverter for supplying the electric motor with an alternating current, and a liquid cooling circuit for transporting a cooling liquid through the engine cooling component and the cooling element of the inverter.

[0009] Against the background of this prior art, the object of the present disclosure is to provide a device and / or a method which are each suitable for enriching the prior art.

[0010] The problem is solved by the features of the independent claims. The subordinate claims and the subclaims each contain optional developments of the disclosure. According to these, the problem is solved by a drive arrangement for a motor vehicle.

[0011] The drive arrangement comprises a first drive unit having a first power electronics unit and a first electric machine.

[0012] The drive arrangement comprises a second drive unit having a second power electronics unit and a second electric machine.

[0013] The drive arrangement comprises a cooling circuit for cooling the first drive unit and the second drive unit using a coolant that can be guided (e.g., circulated) in the cooling circuit. The first power electronics and the second power electronics are arranged upstream of the first electric machine and (upstream of) the second electric machine in the cooling circuit. In other words, in an operating state of the drive arrangement, the coolant first flows through the first power electronics and the second power electronics, and then through the second electric machine and the first electric machine.

[0014] The first drive unit has a first housing in which the first power electronics and the first electric machine (optionally completely) are arranged.

[0015] The second drive unit has a second housing in which the second power electronics and the second electric machine (optionally completely) are arranged.

[0016] It is conceivable that the cooling circuit can be designed not only to cool the first drive unit and the second drive unit, but also to heat the first drive unit and the second drive unit. Accordingly, the cooling circuit can also be designed as a temperature control circuit for temperature control of the first drive unit and the second drive unit using a temperature control fluid that can be guided (e.g., circulated) in the temperature control circuit. “Arranged in the cooling circuit” is to be understood that at least one section of the cooling circuit is formed in and / or on the first power electronics unit, the second power electronics unit, the first electrical machine, and the second electrical machine (and optionally one or more further components). For example, these components can each have one or more channels through which the cooling fluid is passed as it circulates in the cooling circuit.This allows direct or indirect heat exchange between the components and the coolant, thus cooling the components.

[0017] To cool the first power electronics and the first electrical machine, the cooling circuit can flow into and out of the first housing (e.g., through openings and / or via connections in the first housing). Similarly, the cooling circuit for cooling the second power electronics and the second electrical machine can flow into and out of the second housing (e.g., through openings and / or via connections in the second housing).

[0018] “Upstream” and “downstream” refer to an arrangement of the components arranged in the cooling circuit relative to a flow direction or conveying direction of the coolant in an operating state of the drive arrangement. If a first component is arranged upstream of a second component, the coolant flows first through the first component and then through the second component in the operating state of the drive arrangement. In the drive arrangement described above, the coolant flows first through the first power electronics and the second power electronics, and then through the second electrical machine and the first electrical machine. The same applies: If a first component is arranged downstream of a second component, the coolant flows first through the second component and then through the first component in the operating state of the drive arrangement.

[0019] The drive arrangement described above offers a number of advantages. Among other things, it provides a drive arrangement with a cooling topology that allows the power electronics of the multiple drive units to be cooled sequentially before the electrical machines of the multiple drive units, thus providing sufficient flow temperatures for the components to be cooled.

[0020] Compared to a parallel integration of the drive units into the cooling system, the drive arrangement described above roughly halves or at least significantly reduces the amount or volume of coolant required, which, among other things, requires lower pump capacities. Furthermore, no additional components are required for the parallel integration of the drive units and the corresponding branching and merging of the cooling circuit. Compared to a sequential integration of the two drive units in the cooling system, all components can be adequately cooled, ensuring, in particular, sufficiently low flow temperatures for the two power electronics units.

[0021] Possible further developments of the drive arrangement described above are explained in detail below.

[0022] The first power electronics, the second power electronics, the second electric machine and the first electric machine can be arranged in series (or serially) in the cooling circuit.

[0023] The cooling circuit can, for example, consist of a single, closed cooling circuit. The cooling circuit can be designed without branches (or without branches).

[0024] The first power electronics and the first electric machine can be arranged adjacent to each other (optionally directly next to each other). The second power electronics and the second electric machine can be arranged adjacent to each other (optionally directly next to each other).

[0025] The first power electronics unit may comprise a first inverter (e.g., for providing an alternating current for the first electrical machine). The second power electronics unit may comprise a second inverter (e.g., for providing an alternating current for the second electrical machine).

[0026] The drive arrangement can comprise at least one conveying device (for conveying the cooling fluid). The at least one conveying device can be arranged to convey the cooling fluid in the cooling circuit in such a way that, in an operating state of the at least one conveying device and / or the drive arrangement, the conveyed cooling fluid first flows through the first power electronics and the second power electronics, and then through the second electrical machine and the first electrical machine. The at least one conveying device can be or comprise at least one pump.

[0027] The first power electronics may have at least one first power electronics heat exchanger, which may be arranged in the cooling circuit (optionally for cooling the first power electronics or for heat exchange between the cooling liquid and the first power electronics).

[0028] The second power electronics may have at least one second power electronics heat exchanger, which may be arranged in the cooling circuit (optionally for cooling the second power electronics or for heat exchange between the cooling liquid and the second power electronics).

[0029] The first electric machine may have a first machine heat exchanger, which may be arranged in the cooling circuit (optionally for cooling the first electric machine or for heat exchange between the cooling fluid and the first electric machine). The first machine heat exchanger may be or have, for example, an oil-water heat exchanger and / or a stator housing cooling system.

[0030] The second electric machine may have a second machine heat exchanger, which may be arranged in the cooling circuit (optionally for cooling the second electric machine or for heat exchange between the cooling fluid and the second electric machine). The second machine heat exchanger may be or have, for example, an oil-water heat exchanger and / or a stator housing cooling system.

[0031] The drive assembly may include an air-cooled vehicle radiator. The vehicle radiator may be arranged in the cooling circuit downstream of the first power electronics, the second power electronics, the first electric machine, and the second electric machine. The vehicle radiator may be arranged (or is arranged) at the front of the motor vehicle and / or be cooled by ambient air, e.g., a wind during driving operation of the motor vehicle. Accordingly, the vehicle radiator may also be referred to as an ambient cooler.

[0032] The drive assembly may comprise at least one vehicle component. The at least one vehicle component may be arranged and configured for cooling in the cooling circuit downstream of the vehicle radiator and upstream of the first power electronics and the second power electronics such that, in an operating state of the drive assembly, the cooling fluid has a temperature below a maximum flow temperature (optionally directly) before flowing through the first power electronics and / or the second power electronics.

[0033] The above description can be summarized in other words and in a possible more concrete embodiment of the disclosure as described below, whereby the following description is not to be interpreted as limiting the disclosure.

[0034] The drive units can each be separated between a power electronics system (e.g. an inverter) and an electric machine and then reconnected to one another. In concrete terms, the coolant can first flow through the inverter of the first drive unit, then the inverter of the second drive unit, and then the electric machine or the heat exchanger of the electric machine of one of the two drive units. Finally, the coolant can flow through the remaining electric machine or the heat exchanger of the remaining electric machine. Other components of the entire motor vehicle that require cooling can be integrated into the cooling system, i.e. the cooling circuit, at a suitable point. This allows the flow temperature of all inverters to remain at a low level.At the same time, the amount of coolant to be circulated for the drive unit cooling, for example, can be roughly halved.

[0035] In an electrically powered motor vehicle, a first drive unit can be used in the front area and a second drive unit in the rear area.

[0036] The first drive unit in the front area can be separated between the inverter and the electric motor or the electric motor's cooler, e.g., an (oil-water) heat exchanger. Similarly, the second drive unit in the rear area can be separated between the inverter and the electric motor or the electric motor's cooler, e.g., an (oil-water) heat exchanger.

[0037] The coolant can first flow through the inverter at the front of the vehicle and then to the rear of the vehicle, where it then cools the inverter at the rear. The coolant can then cool the electric motor (or heat exchanger) at the rear, flow to the front of the vehicle, and cool the electric motor (or heat exchanger) at the front. The coolant can then flow to the vehicle's radiator (or ambient cooler).

[0038] Furthermore, a motor vehicle comprising the drive arrangement described above is provided.

[0039] The motor vehicle may be a passenger car, in particular an automobile, or a commercial vehicle, such as a truck.

[0040] The first drive unit can be arranged in a front region of the motor vehicle. The second drive unit can be arranged in a rear region of the motor vehicle. The drive arrangement can be designed such that, in an operating state of the drive arrangement, the cooling fluid flows through the first power electronics in the front region, (optionally after flowing through the first power electronics) is guided from the front region to the rear region by means of the cooling circuit and flows through the second power electronics, (optionally after flowing through the second power electronics) flows through the second electric machine, and (optionally after flowing through the second electric machine) is guided from the rear region back to the front region by means of the cooling circuit and flows through the first electric machine.The drive arrangement can be designed such that the cooling liquid flows through the vehicle radiator after flowing through the first electric machine.

[0041] The motor vehicle can be an electrically powered motor vehicle (also known as an electric vehicle), e.g. a battery-electric vehicle, a hybrid vehicle or a fuel cell vehicle.

[0042] What has been described above with reference to the drive arrangement also applies analogously to the motor vehicle and vice versa.

[0043] An optional embodiment is described below with reference to Figures 1 and 2.

[0044] Fig. 1 shows schematically a drive arrangement according to the disclosure for a motor vehicle, and

[0045] Fig. 2 shows schematically the motor vehicle with the drive arrangement.

[0046] The drive arrangement 1, which is shown only schematically in Figure 1, comprises a first drive unit 2, a second drive unit 3 and a cooling circuit 4 for cooling the first drive unit 2 and the second drive unit 3 by means of a coolant that can be guided, e.g., circulated, in the cooling circuit 4. The first drive unit 2 has a first power electronics unit 2.1, a first electrical machine 2.2 and a first housing 2.3 in which the first power electronics unit 2.1 and the first electrical machine 2.2 are arranged. The first power electronics unit 2.1 can have a first inverter for providing an alternating current for the first electrical machine 2.2, wherein the first inverter is arranged, e.g., for cooling in and / or on the cooling circuit 4. The first power electronics unit 2.1 can, for example, have at least one first power electronics heat exchanger that is arranged in the cooling circuit 4.The first electric machine 2.2 can, for example, have a first machine heat exchanger arranged in the cooling circuit 4.

[0047] The second drive unit 3 has a second power electronics unit 3.1, a second electric machine 3.2 and a second housing 3.3 in which the second power electronics unit 3.1 and the second electric machine 3.2 are arranged. The second power electronics unit 3.1 can have a second inverter for providing an alternating current for the second electric machine 3.2, wherein the second inverter is arranged, for example, for cooling in and / or on the cooling circuit 4. The second power electronics unit 3.1 can, for example, have at least one second power electronics heat exchanger which is arranged in the cooling circuit 4. The second electric machine 3.2 can, for example, have a second machine heat exchanger which is arranged in the cooling circuit 4.

[0048] The first power electronics 2.1 and the second power electronics 3.1 are arranged upstream of the first electric machine 2.2 and the second electric machine 3.2 in the cooling circuit 4, wherein the first power electronics 2.1, the second power electronics 3.1, the second electric machine 3.2 and the first electric machine 2.2 can be arranged in series (or serially) in the cooling circuit 4.

[0049] The drive arrangement 1 comprises at least one conveying device 5, e.g., a pump. The at least one conveying device 5 can be arranged in the cooling circuit 4 to convey the cooling fluid such that, in an operating state of the at least one conveying device 5 and / or the drive arrangement 1 (i.e., when the cooling fluid is conveyed or circulated), the conveyed cooling fluid first flows through the first power electronics unit 2.1 and the second power electronics unit 3.1 and then through the second electric machine 2.2 and the first electric machine 3.2.

[0050] In the embodiment shown, the drive assembly 1 comprises at least one air-cooled vehicle cooler 6, which is arranged in the cooling circuit 4 downstream of the first power electronics unit 2.1, the second power electronics unit 3.1, the first electric machine 2.2, and the second electric machine 3.2. The vehicle cooler 6 serves to cool the coolant. The vehicle cooler can be arranged at a front of the motor vehicle 10 and can thus be cooled by the outside air, in particular by the wind when the motor vehicle 10 is in motion.

[0051] The drive assembly 1 can further comprise one or more vehicle components 7, which can be arranged in the cooling circuit 4. At least one vehicle component 7 can be arranged and configured for cooling in the cooling circuit 4 downstream of the vehicle radiator 6 and upstream of the first power electronics 2.1 and the second power electronics 3.1 such that the coolant, in an operating state of the drive assembly 1, has a temperature below a maximum flow temperature directly before flowing through the first power electronics 2.1 and / or the second power electronics 3.1.

[0052] Furthermore, it is conceivable that one or more (not shown) vehicle components for cooling and / or one or more (not shown) components, e.g., valves, can be arranged at other suitable locations in the cooling circuit 7. These can, for example, also be positions between two of the first power electronics 2.1, the second power electronics 3.1, the first electric machine 2.2, and the second electric machine 3.2.

[0053] The arrows shown in Figure 1 indicate a flow direction or conveying direction of the cooling fluid in the operating state of the drive assembly 1, i.e., when the cooling fluid is conveyed, for example, by the conveying device 5 and circulates in the cooling circuit 4. Figure 2 shows the motor vehicle 10 comprising the drive assembly 1, wherein the motor vehicle 10 may be an electrically driven motor vehicle (or an electric vehicle).

[0054] The first drive unit 2 can be arranged in a front region 10.1 of the motor vehicle 10, e.g., for driving at least one front wheel or one front axle of the motor vehicle 10. The second drive unit 3 can be arranged in a rear region 10.2 of the motor vehicle 10, e.g., for driving at least one rear wheel or one rear axle of the motor vehicle 10. Accordingly, the motor vehicle can be, for example, an all-wheel drive vehicle.

[0055] It is conceivable that the drive arrangement 1 in the configuration shown can be designed such that the cooling liquid in the operating state of the drive arrangement 1 flows through the first power electronics 2.1 in the front area 10.1, is guided by means of the cooling circuit 4 from the front area 10.1 into the rear area 10.2 and flows through the second power electronics 3.1, then flows through the second electric machine 3.2, and finally is guided by means of the cooling circuit 4 from the rear area 10.2 back into the front area 10.1 and flows through the first electric machine 2.2.

[0056] List of reference symbols

[0057] 1 drive arrangement

[0058] 2 first drive unit 2.1 first power electronics

[0059] 2.2 first electric machine

[0060] 2.3 first housing

[0061] 3 second drive unit

[0062] 3.1 second power electronics 3.2 second electric machine

[0063] 3.3 second housing

[0064] 4 Cooling circuit

[0065] 5 Conveyor system

[0066] 6 Vehicle radiator 7 Vehicle component(s)

[0067] 10 motor vehicle

[0068] 10.1 Front area of ​​the motor vehicle

[0069] 10.2 Rear area of ​​the motor vehicle

Claims

Patent claims 1. Drive arrangement (1) for a motor vehicle (10), the drive arrangement (1) comprising: - a first drive unit (2) having a first power electronics unit (2.1) and a first electric machine (2.2); - a second drive unit (3) having a second power electronics unit (3.1) and a second electric machine (3.2); and - a cooling circuit (4) for cooling the first drive unit (2) and the second drive unit (3) by means of a cooling liquid that can be guided in the cooling circuit (4), wherein the first power electronics (2.1) and the second power electronics (3.1) are arranged upstream of the first electrical machine (2.2) and the second electrical machine (3.2) in the cooling circuit (4), characterized in that - the first drive unit (2) has a first housing (2.3) in which the first power electronics (2.1) and the first electric machine (2.2) are arranged, and - the second drive unit (3) has a second housing (3.3) in which the second power electronics (3.1) and the second electrical machine (3.2) are arranged.

2. Drive arrangement (1) according to claim 1, characterized in that the first power electronics (2.1), the second power electronics (3.1), the second electrical machine (3.2) and the first electrical machine (2.2) are arranged in series in the cooling circuit (4).

3. Drive arrangement (1) according to claim 1 or 2, characterized in that - the first power electronics (2.1) comprises a first inverter for providing an alternating current for the first electrical machine (2.2), and / or - the second power electronics (3.1) comprises a second inverter for providing an alternating current for the second electrical machine (3.2).

4. Drive arrangement (1) according to one of claims 1 to 3, characterized in that the drive arrangement (1) comprises: - at least one conveying device (5) arranged to convey the cooling liquid in the cooling circuit (4) in such a way that the conveyed cooling liquid, in an operating state of the at least one conveying device (5) and / or the drive arrangement (1), first flows through the first power electronics (2.1) and the second power electronics (3.1) and then through the first electrical machine (2.2) and the second electrical machine (3.2).

5. Drive arrangement (1) according to one of claims 1 to 4, characterized in that the first power electronics (2.1) has at least one first power electronics heat exchanger which is arranged in the cooling circuit (4), and / or - the second power electronics (3.1) comprises at least one second power electronics heat exchanger arranged in the cooling circuit (4); and / or - the first electrical machine (2.2) has a first machine heat exchanger which is arranged in the cooling circuit (4), and / or - the second electrical machine (3.2) has a second machine heat exchanger which is arranged in the cooling circuit (4).

6. Drive arrangement (1) according to one of claims 1 to 5, characterized in that the drive arrangement (1) comprises: - an air-cooled vehicle cooler (6) which is arranged in the cooling circuit (4) downstream of the first power electronics (2.1), the second power electronics (3.1), the first electrical machine (2.2) and the second electrical machine (3.2).

7. Drive arrangement (1) according to claim 6, characterized in that the drive arrangement (1) comprises: - at least one vehicle component (7) which is arranged and designed for cooling in the cooling circuit (4) downstream of the vehicle radiator (6) and upstream of the first power electronics (2.1) and the second power electronics (3.1) in such a way that the cooling liquid, in an operating state of the drive arrangement (1), has a temperature below a maximum flow temperature directly before flowing through the first power electronics (2.1) and / or the second power electronics (3.1).

8. Motor vehicle (10), characterized in that the motor vehicle (10) comprises the drive arrangement (1) according to one of the preceding claims.

9. Motor vehicle (10) according to claim 8, characterized in that - the first drive unit (2) is arranged in a front area (10.1) of the motor vehicle (10), and - the second drive unit (3) is arranged in a rear region (10.2) of the motor vehicle (10).

10. Motor vehicle (10) according to claim 9, characterized in that the drive arrangement (1) is designed such that the cooling liquid in an operating state of the drive arrangement (1): - the first power electronics (2.1 ) in the front area (10.1 ) flows through, - is guided by means of the cooling circuit (4) from the front area (10.1) to the rear area (10.2) and flows through the second power electronics (3.1), - flows through the second electrical machine (3.2), and - is led from the rear area (10.2) back to the front area (10.1) by means of the cooling circuit (4) and flows through the first electric machine (2.2).

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