Electric drive system for a motor vehicle, in particular for a car

Abstract

The invention relates to an electric drive system (10) for a motor vehicle, comprising at least one electric machine (12) by means of which the motor vehicle can be driven, an inverter (14) associated with the electric machine (12) by means of which the electric machine (12) can be supplied with electrical energy, a hydraulic device (16), and at least one pump (18a, b) for pumping a hydraulic fluid with which the hydraulic device (16) can be supplied, wherein the pump (18a, b) is arranged between the hydraulic device (16) and the inverter (14).

Description

[0001] The invention relates to an electric drive system for a motor vehicle, in particular for a motor vehicle, according to the preamble of patent claim 1.

[0002] US 2021 / 0129660 A1 discloses a drive module for a vehicle, comprising an electric motor and an inverter. DE 10 2018 109 614 A1 shows, for an electric vehicle, an arrangement of a hydraulic pump and a hydraulic device in conjunction with a voltage converter. The generic DE 10 2022 133 885 A1 shows an electric drive system for a motor vehicle, comprising an electric motor, an inverter, a hydraulic device, and a hydraulic pump.

[0003] The object of the present invention is to provide an electric drive system for a motor vehicle so that a particularly compact design of the electric drive system can be realized.

[0004] This object is achieved by an electric drive system having the features of patent claim 1. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0005] The invention relates to an electric drive system, also referred to as an electric drive device, for a motor vehicle, also simply referred to as a vehicle, which is preferably designed as a motor vehicle, in particular as a passenger car. This means that the motor vehicle, in its fully manufactured state, has the electric drive system and can be driven by means of the electric drive system, in particular purely electrically. The electric drive system has at least or exactly one electric machine, by means of which the motor vehicle can be driven, in particular purely electrically. For this purpose, the electric machine can be operated in motor mode and thus as an electric motor, by means of which the motor vehicle can be driven, in particular purely electrically. The electric machine is therefore also referred to as a drive motor or electric drive motor.The electric drive system also has an inverter, also referred to as a power inverter or rotary inverter, via which the electric machine can be supplied with electrical energy. By supplying the electric machine with electrical energy, the electric machine can be operated in motor mode. The inverter is a power electronics unit or a component of a power electronics unit, such that the electric machine can be supplied with electrical energy via the power electronics and can thus be operated in motor mode. The electrical energy can be provided, for example, by an electrical energy store of the motor vehicle, wherein the electrical energy is to be stored or is stored in the electrical energy store, in particular electrochemically. The electrical energy store can be a component of the electric drive system.Preferably, the electrical machine is a high-voltage component whose electrical voltage, in particular the electrical operating or rated voltage, is preferably greater than 50 volts, in particular greater than 60 volts, and very preferably amounts to several hundred volts. Furthermore, it is conceivable that the electrical energy storage device is a high-voltage component whose electrical voltage, in particular the electrical operating or rated voltage, is preferably greater than 50 volts, in particular greater than 60 volts, and very preferably amounts to several hundred volts.

[0006] The electric drive system also comprises a hydraulic device and at least one pump for conveying a hydraulic fluid. The hydraulic device can be supplied with the hydraulic fluid conveyed by the pump. Alternatively or additionally, the hydraulic fluid conveyed by the pump can be discharged by the hydraulic device. Thus, for example, the hydraulic device can be supplied with the hydraulic fluid, also referred to as the hydraulic medium, via the pump. Alternatively or additionally, the hydraulic fluid can be discharged from the hydraulic device via the pump. In particular, the pump is an electrically operated pump, i.e., an electric pump.Preferably, the pump is a component external to the hydraulic device, and is therefore arranged outside the hydraulic device, and preferably the hydraulic device is a component external to the pump, and is therefore arranged outside the pump. Very particularly, it is provided that the hydraulic device is arranged downstream of the pump in the flow direction of the hydraulic fluid conveyed by the pump. Furthermore, it is conceivable that the hydraulic device is arranged upstream of the pump in the flow direction of the hydraulic fluid conveyed by the pump. For example, the hydraulic device comprises at least one consumer which can be supplied with the hydraulic fluid conveyed by the pump. In particular, the consumer can, for example, be actuated and / or operated by means of the hydraulic fluid conveyed by the pump, i.e. be hydraulically actuated and / or hydraulically operated.Furthermore, it is conceivable that the hydraulic fluid delivered by the pump can be drained away from the consumer, i.e. guided away. Hydraulic fluid is preferably a component of the electric drive system. The hydraulic fluid can be oil, for example. The aforementioned pump is also referred to as the first pump. The electric drive system can have at least or exactly two pumps for pumping the hydraulic fluid, namely the first pump and a second pump provided in addition to the first pump. The previous and following explanations regarding the first pump can also be applied directly to the second pump and vice versa. When reference is made above and below to the pump, this also refers to the first pump, unless stated otherwise.

[0007] In order to be able to realize a particularly compact design of the electric drive system, so that the electric drive system has a particularly small installation space requirement, it is provided in a manner known per se that the pump is arranged between the hydraulic device and the inverter, in particular along a particularly straight viewing direction, thus running along a straight line, so that in particular the hydraulic device, also simply referred to as hydraulics, is at least partially overlapped by the pump and thus covered in a first direction running parallel to the viewing direction or coinciding with the viewing direction, which runs or points from the hydraulic device towards the inverter, and so that in particular the inverter is arranged in a second direction coinciding with the viewing direction or parallel to the viewing direction,which is opposite to the first direction and runs or points from the inverter towards the hydraulic device, is at least partially overlapped by the pump. In other words, the pump, the hydraulic device and the inverter are arranged according to a sandwich arrangement, the core layer of which, also simply referred to as the core, is formed by the pump, so to speak, wherein the hydraulic device and the inverter form cover layers of the sandwich arrangement, so to speak, wherein the core layer is arranged between the cover layers, in particular along the viewing direction. In particular, the invention thereby enables a spring-loaded and / or blind contacting of the pump, which is designed, for example, as an oil pump. In other words, the invention allows the pump to be mounted in a method for producing the electric drive system in such a way that the pump is connected, in particular fluidically, to the hydraulic device and, in particular electrically,can be connected to the inverter without the person assembling the pump being able to see, i.e., visually perceive, the respective connection points where the pump is connected to the hydraulic system on the one hand and to the inverter on the other. This allows the electric drive system to be manufactured particularly quickly and cost-effectively. Furthermore, a particularly space-efficient integration of the pump into the electric drive system is possible.

[0008] In particular, it is conceivable for the pump to be supplied with electrical energy via the inverter for electrically operating the pump. The invention allows for particularly short cable lengths between the pump, in particular an electric motor of the pump, and the inverter or the power electronics, thus enabling particularly efficient operation. The inverter or the power electronics can, for example, be leak-tested, i.e., delivered in a state in which the power electronics have already been leak-tested, since the aforementioned blind contacting of the power electronics to the pump is possible with the invention.

[0009] In order to minimize the installation space requirements of the electric drive system, the hydraulic device according to the invention comprises a hydraulic plate with valves by means of which the flow of the hydraulic fluid, which is delivered in particular by the pump, can be influenced. The pump is arranged between the inverter and the hydraulic plate, particularly along the viewing direction.

[0010] In an advantageous embodiment of the invention, the electric drive system has a housing which has a first housing part and a housing cover as a second housing part which is formed separately from the first housing part and is connected to the first housing part, in particular in a non-destructively detachable manner.

[0011] To achieve a particularly compact design, it has proven particularly advantageous if the inverter and / or the pump are arranged within the housing cover and preferably outside the first housing part. For example, the electric drive system has a receiving area, also referred to as a receiving space, which is, for example, partially delimited, in particular directly delimited, by the housing cover, in particular by a first surface of the housing cover, and partially by the first housing part, in particular by a second surface of the first housing part. Preferably, the inverter and / or pump are arranged in the receiving area and thus within the housing cover.In particular, the feature that the pump is arranged inside the housing cover is to be understood as meaning that the pump is arranged, in particular along the viewing direction, between the inverter and a flange plane of the housing cover, which is supported in the flange plane, in particular directly, on the first housing part.

[0012] For example, the first housing part is a transmission housing of a transmission of the electric drive system, wherein the motor vehicle can be driven, in particular purely electrically, via the transmission by means of the electric machine.

[0013] A further embodiment is characterized in that the pump has a cylindrical shape on its outer circumference, thus being designed in the form of a cylinder. The cylinder is very preferably a right circular cylinder. Expressed again in other words, the pump preferably has the shape of a cylinder on its outer circumference, which is preferably a right circular cylinder. The cylinder, i.e., the cylindrical shape, has a cylinder axis with respect to which the cylinder is rotationally symmetrical. In particular, the cylinder axis coincides with a longitudinal direction of the cylinder.

[0014] Preferably, at a first end of the cylindrical shape, and thus of the cylinder, at least one or exactly one fluid outlet is arranged, via which the hydraulic fluid delivered by the pump can be discharged from the pump and, for example, supplied to a hydraulic device. At a second end of the cylindrical shape, and thus of the cylinder, at least one or exactly one electrical contact for the pump is arranged, wherein the second end is opposite the first end, in particular along the cylinder axis. For example, at the first end, a first axial end face of the cylindrical shape and thus of the pump is arranged, such that the fluid outlet is arranged on the first axial end face. For example, at the second end of the cylindrical shape, a second axial end face of the cylindrical shape and thus of the pump is arranged, such that, for example, the electrical contact for the pump is arranged on the second axial end face.The second axial end face points away from the first axial end face along the cylinder axis, and the first axial end face points away from the second axial end face along the cylinder axis. The electrical contact of the pump is also referred to as the first electrical contact. When electrical contact is mentioned above and below, this means, unless otherwise stated, the first electrical contact of the pump. In particular, the pump can be supplied with electrical energy for, in particular electrical, operation of the pump via the electrical contact. For example, the electrical contact of the pump is or comprises at least or precisely one electrical contact element, via which, for example, the pump can be supplied with electrical energy for, in particular electrical, operation of the pump.Thus, it is particularly conceivable that the pump is electrically contacted with the inverter via the electrical contact of the pump, i.e. is electrically connected to the inverter, so that the electrical contact of the pump can be supplied with electrical energy via the inverter, whereby the pump can be supplied with electrical energy for, in particular, electrical, operation of the pump via the inverter and the electrical contact of the pump.

[0015] In particular, the pump is fluidly connected to the hydraulic system via the fluid outlet, so that the hydraulic fluid flowing through the fluid outlet and thus out of the pump can be fed to the hydraulic system via the fluid outlet, i.e., introduced into the hydraulic system. This allows for a particularly small installation space requirement for the electric drive system.

[0016] In order to keep the installation space requirement of the electric drive system particularly low and to be able to manufacture the electric drive system particularly simply and thus cost-effectively, in particular in such a way that the pump can be blindly contacted with the hydraulic device and with the inverter, it is provided in a further embodiment of the invention that the fluid outlet, in particular along the viewing direction, points towards the hydraulic plate, thus facing the hydraulic plate, wherein preferably the electrical contact of the pump, in particular along the viewing direction, points towards the inverter, ie facing the inverter.

[0017] Another embodiment is characterized in that the inverter has a circuit board.

[0018] In order to keep the installation space requirements of the electric drive system particularly small, a further embodiment of the invention provides for a first plane, which runs within the circuit board of the inverter, to run parallel to a second plane, which runs within the hydraulic plate. To achieve particularly small installation space requirements, it has proven particularly advantageous if the pump is arranged between the inverter and the hydraulic plate in a direction perpendicular to the planes, which is, for example, the aforementioned viewing direction.

[0019] Finally, to achieve particularly low installation space requirements, it has proven particularly advantageous if the circuit board has at least one electrical contact, also referred to as a second electrical contact, on a side of the circuit board facing the pump, particularly along the viewing direction. For example, the second electrical contact is or comprises at least or exactly one second electrical contact element.For example, it can be provided that the second electrical contact of the circuit board is electrically connected, in particular directly, to the first electrical contact of the pump, so that, for example, the inverter can provide the electrical energy for, in particular electrically, operating the pump via the second electrical contact, wherein the electrical energy provided or provideable by the inverter via the second electrical contact for, in particular electrically, operating the pump can be transferred from the second electrical contact, in particular directly, to the first electrical contact, as a result of which the pump can be supplied with the electrical energy provided or provideable by the inverter via the second electrical contact. The pump can thereby be operated, in particular electrically.

[0020] Further advantages, features, and details of the invention will become apparent from the following description of a preferred embodiment and from the drawings. The features and combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures, can be used not only in the respective specified combinations, but also in other combinations or on their own, without departing from the scope of the invention.

[0021] The drawing shows: Fig. 1 shows a partial schematic and sectional side view of an electric drive system for a motor vehicle; and Fig. 2 a partial schematic and sectional top view of the electric drive system.

[0022] In the figures, identical or functionally identical elements are provided with the same reference symbols.

[0023] Fig. 1 shows a partial schematic and sectional side view of an electric drive system 10 for a motor vehicle, also referred to simply as a vehicle, which is preferably designed as a motor vehicle, in particular as a passenger car, and is drivable, in particular purely electrically, by means of the electric drive system 10. The electric drive system 10 has at least one Fig. 1 has an electrical machine 12, shown particularly schematically, which can be operated in motor mode and thus as an electric motor. In motor mode, the electrical machine 12 can drive the motor vehicle. The electrical drive system 10 also has an inverter 14, which is a power electronics unit or is a component of a power electronics unit. The inverter 14, also referred to as an inverter, can supply the electrical machine 12 with electrical energy, whereby the electrical machine 12 can be operated in motor mode. The electrical drive system 10 also has a hydraulic device 16, also referred to simply as hydraulics, and two pumps 18a and 18b, by means of which a hydraulic fluid, also referred to as hydraulic medium, can be pumped. The respective pump 18a, b is designed as an electrically operated pump, thus as an electric pump.The hydraulic device 16 can, for example, be supplied with the hydraulic fluid delivered by the respective pump 18a, b. The hydraulic fluid is preferably an oil, so that, for example, the respective pump 18a, b is designed as a respective oil pump.

[0024] In order to be able to realize a particularly compact design of the electric drive system 10, the pumps 18a and 18b are arranged in particular along a Fig. 1 by a double arrow 20 between the hydraulic device 16 and the inverter 14, thus the power electronics.

[0025] The viewing direction is straight, i.e. along an imaginary straight line.

[0026] In the Fig. 1 and Fig. In the embodiment shown in Figure 2, the electric drive system 10 has a housing 22, which has a first housing part 24 and a second housing part 26. The second housing part 26 is a housing cover of the housing 22. The housing parts 24 and 26 are formed separately from one another and are connected to one another, in particular in a non-destructive manner. For example, the housing part 24 is a transmission housing of a Fig. 1 shows a section of the transmission 28 of the drive system 10. For example, the electric machine 12 can drive the motor vehicle via the transmission 28. It can be seen that a receiving area 30, also referred to as a receiving space, is partially delimited by the housing cover, in particular partially by a first surface 32 of the housing cover, and partially by the housing part 24, in particular partially by a second surface 34 of the housing part 24, in particular in each case directly, wherein the pumps 18a and 18b are arranged in the receiving area 30. The hydraulic device 16 is also at least partially arranged in the receiving area 30. The housing cover is arranged outside the housing part 24, and the housing part 24 is arranged outside the housing cover.

[0027] In the Fig. 1 and Fig. In the embodiment shown in Figure 2, the pumps 18a and 18b are arranged in the receiving area 30 and thus within the housing cover and, in particular, completely outside the first housing part 24. Furthermore, it is conceivable that, alternatively or additionally, the inverter 14 is arranged within the housing cover.

[0028] The hydraulic device 16 has a hydraulic plate 36 with Fig. 1, valves 38 are shown particularly schematically, by means of which the flow of hydraulic fluid can be influenced. The pumps 18a and 18b are arranged, particularly along the viewing direction (double arrow 20), between the inverter 14 and the hydraulic plate 36.

[0029] From a summary of Fig. 1 and Fig. 2 it can be seen that the respective pump 18a, b has a cylindrical shape on its outer circumference and is thus designed in the shape of a cylinder, which is a right circular cylinder. At least one respective fluid outlet A of the respective pump 18a, b is arranged at a respective first end E1 of the respective cylindrical shape of the respective pump 18a, b, wherein the respective pump 18a, b is fluidly connected to the hydraulic device 16, in particular fluidly connected to the hydraulic plate 36, via its respective fluid outlet A. Via the respective fluid outlet A, the hydraulic fluid delivered by the respective pump 18a, b can be discharged from the respective pump 18a, b and fed to the hydraulic device 16, i.e. introduced into the hydraulic device 16, or vice versa. The respective cylindrical shape of the respective pump 18a, b has a respective second end E2 opposite the respective first end E1.Respective first electrical contacts 40 of the respective pump 18a, b are arranged at the respective second end E2 of the respective pump 18a, b, which is opposite the respective first end E1 of the respective pump 18a, b. The respective pump 18a, b is electrically connected to the inverter 14 via its respective first electrical contacts 40, such that the respective pump 18a, b can be supplied with electrical energy, in particular for electrically operating the respective pump 18a, b, via the inverter 14 and the respective first electrical contacts 40 of the respective pump 18a, b. Fig. 1 it can be seen that the respective fluid outlet A of the respective pump 18a, b points in particular along the viewing direction to the hydraulic plate 36, wherein the respective first electrical contacts 40 of the respective pump 18a, b point in particular along the viewing direction to the inverter 14.

[0030] Out of Fig. 1 that the inverter 14 has a circuit board 42, which is also referred to as a printed circuit board or is designed as a printed circuit board. In particular, electrical or electronic components of the inverter 14 (not shown in the figures) are arranged on the circuit board 42, in particular such that the electrical or electronic components of the inverter 14 are carried by the circuit board 42 of the inverter 14. In this case, it is provided that a Fig. 1 schematically shown, first plane B1, which runs within the board 42, parallel to a plane in Fig.1, wherein both the plane B1 and the plane B2 are perpendicular to the viewing direction (double arrow 20). The pumps 18a and 18b are arranged along the viewing direction perpendicular to the planes B1 and B2 between the inverter 14, in particular the circuit board 42, and the hydraulic device 16, in particular the hydraulic plate 36. The circuit board 42 has second electrical contacts 44 and 46 on a side S facing the respective pump 18a, b, in particular along the viewing direction. The second electrical contacts 44 correspond to the first electrical contacts 40 of the pump 18a, such that the second electrical contacts 44 are electrically connected to the first electrical contacts 40 of the pump 18a.are thus contacted. The second electrical contacts 46 correspond to the first electrical contacts 40 of the pump 18b, in this case such that the second electrical contacts 46 are electrically connected to the first electrical contacts 40 of the pump 18b, and are thus contacted. The inverter 14, in particular the circuit board 42, can provide the electrical energy for, in particular electrically, operating the respective pump 18a, b via the respective second electrical contacts 44, 46, wherein the electrical energy provided or can be provided by the inverter 14, in particular by the circuit board 42, and intended for, in particular electrically, operating the respective pump 18a, b can be transferred from the electrical contacts 44 to the electrical contacts 40 of the pump 18a and from the electrical contacts 46 to the electrical contacts 40 of the pump 18b.whereby the pump 18a can be supplied via the electrical contacts 40 of the pump 18a and the pump 18b via the electrical contacts 40 of the pump 18b with the electrical energy provided by the inverter 14, in particular by the circuit board 42, and intended for the, in particular electrical, operation of the respective pump 18a, b, in order to operate the respective pump 18a, b, in particular electrically.

[0031] It can be seen that the installation space requirement of the drive system 10 can be kept particularly small, particularly along the viewing direction. Furthermore, for example, in a method for manufacturing the electric drive system 10, a blind connection or contact, also referred to as blind contacting, of the respective pump 18a, b can be realized both with the inverter 14 and with the hydraulic device 16.This means that, for example, a person assembling the respective pump 18a, b in the aforementioned method can connect the respective pump 18a, b both fluidically to the hydraulic device 16 and electrically to the inverter 14 in such a way that the respective fluid outlet A of the respective pump 18a, b is fluidically connected to the hydraulic device 16 and the respective first electrical contacts 40 of the respective pump 18a, b is or are electrically connected to the respective corresponding second electrical contacts 44, 46, without the person having to or being able to visually perceive the respective fluid outlet A of the respective pump 18a, b or the electrical contacts of the respective pump 18a, b or the electrical contacts 44, 46 of the inverter 14 during assembly of the respective pump 18a, b. As a result, the electric drive system 10 can be manufactured in a particularly time- and cost-effective manner.

Claims

[1] Electric drive system (10) for a motor vehicle, with at least one electric machine (12) by means of which the motor vehicle can be driven, with an inverter (14) assigned to the electric machine (12) via which the electric machine (12) can be supplied with electrical energy, with a hydraulic device (16), and with at least one pump (18a, b) for conveying a hydraulic fluid, wherein the pump (18a, b) is arranged between the hydraulic device (16) and the inverter (14), characterized by , that the hydraulic device (16) has a hydraulic plate (36) with valves (38) by means of which a flow of the hydraulic fluid can be influenced, wherein the pump (18a, b) is arranged between the inverter (14) and the hydraulic plate (36). [2] Electric drive system (10) according to claim 1, characterized bya housing (22) which has a first housing part (24) and a housing cover formed separately from the first housing part (24) and connected to the first housing part (24) as a second housing part (26). [3] Electric drive system (10) according to claim 2, characterized by that the inverter (14) and / or the pump (18a, b) is arranged within the housing cover. [4] Electric drive system (10) according to one of the preceding claims, characterized by that the pump (18a, b) has a cylindrical shape on the outer circumference, on which: - a fluid outlet (A) is arranged at the first end (E1), via which the hydraulic fluid delivered by the pump (18A, B) can be discharged from the pump (18a, b); and - at least one electrical contact (40) of the pump (18a, b) is arranged at the second end (E2) opposite the first end (E1). [5] Electric drive system (10) according to claim 4, characterized by , that: - the fluid outlet (A) points to the hydraulic plate (36); and - the electrical contact (40) points to the inverter (14). [6] Electric drive system (10) according to one of the preceding claims, characterized by that the inverter (14) has a circuit board (42). [7] Electric drive system (10) according to claim 6, characterized by that a first plane (B1) which runs within the circuit board (42) of the inverter (14) runs parallel to a second plane (B2) which runs within the hydraulic plate (36). [8] Electric drive system (10) according to claim 7, characterized by that the pump (18a, b) is arranged between the inverter (14) and the hydraulic plate (36) along a direction (20) perpendicular to the planes (B1, B2). [9] Electric drive system (10) according to one of claims 6 to 8, characterized bythat the circuit board (42) has at least one electrical contact (44, 46) on a side (S) of the circuit board (42) facing the pump (18a, b).

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