Electrical power supply unit for an electric machine of an electrically operated drive train of a motor vehicle

Abstract

Electrical power supply unit (1) for an electric machine (2) of an electrically operated drive train (3) of a motor vehicle (4), comprising an inverter assembly (5) with a first busbar pair (6) and an EMC filter assembly (7) with a second busbar pair (8), wherein the busbar pairs (6, 8) have a connection area (9) in which a busbar (20, 21) of the first busbar pair (6) is electrically connected to a busbar (22, 23) of the second busbar pair (8) via an electrical contacting means (10), where The electrical contacting means (10) each comprise an insulating sleeve (11), each of which is formed from a cylindrical ring-shaped current-conducting element (13) received in an electrically insulating cylindrical shell (12) and which are each arranged between one of the busbars (20, 21) of the first busbar pair (6) and one of the busbars (22, 23) of the second busbar pair (8) such that one of the current-conducting elements (13) is electrically conductively in contact with one of the busbars (20, 21) of the first busbar pair (6) and with one of the busbars (22, 23) of the second busbar pair (8) and the current-conducting element (13) is penetrated by a fastening means (14) by means of which one of the busbars (20, 21) of the first busbar pair (6) and one of the busbars (22, 23) of the second busbar pair (8) are brought towards each other in the longitudinal extension (15) of the insulating sleeve (11). They are characterized by the fact that they are tense. the fastening means (14) each extend with play through one of the cylindrical ring-shaped current-conducting elements (13).

Description

[0001] The present invention relates to an electrical power supply device for an electric machine of an electrically operated drive train of a motor vehicle, comprising an inverter assembly with a first busbar pair and an EMC filter assembly with a second busbar pair, wherein the busbar pairs have a connection area in which a busbar of the first busbar pair is electrically connected to a busbar of the second busbar pair via an electrical contacting means.

[0002] Electric motors are increasingly being used for propulsion in motor vehicles to create alternatives to combustion engines that require fossil fuels. Considerable efforts have already been made to improve the everyday usability of electric drives and to offer users the familiar driving comfort.

[0003] Such axial and radial flux electric machines are typically powered by a power electronics module, also known as an inverter. There is a continuing need to design the inverter and the electric machine to be as compact as possible and to optimize their manufacturing and assembly processes.

[0004] When several electronic devices are arranged in close proximity to each other, as is the case, for example, in an electric axle drive train of a motor vehicle, it is necessary to protect the respective electronic devices from the electromagnetic radiation of the other electronic devices, since the electromagnetic radiation can interfere with the respective electronic functions of the components, which is regularly undesirable.

[0005] Therefore, so-called EMC filters are typically installed upstream of the inverter. These filters smooth the electrical current from an external source, such as a vehicle battery, and then forward it to the inverter module. For reasons of space and manufacturability, the EMC filter and inverter are usually two separate assemblies. For electromagnetic compatibility (EMC) reasons, these two assemblies are often also separated and shielded from each other, positioned within or on the electric motor or drivetrain. Consequently, the busbars at the output of the EMC filter must be connected to those at the input of the inverter.

[0006] Various high-voltage interfaces have become known from the publications DE 10 2022 206 634 A1, DE 10 2022 105 371 B3 and DE 10 2021 117 336 B3.

[0007] The object of the invention is therefore to provide an electrical power supply device for an electric machine of an electrically operated drive train of a motor vehicle, which enables safe and EMC-optimized electrical contacting between the EMF filter assembly and the inverter assembly.

[0008] This problem is solved by an electrical power supply device for an electric machine of an electrically operated drive train of a motor vehicle with the features of claim 1 or claim 2.

[0009] A significant advantage of the electrical power supply device according to the invention lies in the introduction of insulating sleeves, which are formed from an electrically insulating cylindrical ring and a current-conducting element embedded therein, for connecting the busbar pairs of the inverter and EMC filter assemblies. This offers the advantage of high electromagnetic compatibility through effective insulation, while simultaneously maintaining a stable electrical connection between the assemblies. The clamping of the busbars with the fastening elements along the longitudinal extent of the insulating sleeves achieves high mechanical strength of the connection, thereby ensuring a durable and reliable contact even under vibrations and other mechanical stresses typical of automotive operation.Furthermore, the insulation sleeves enable simplified assembly and a reduction in susceptibility to interference through reduced electromagnetic interference.

[0010] Depending on the geometric configuration of the positional relationship between the EMC filter assembly and the inverter assembly, the electrical energy transmission paths between these assemblies are ensured by appropriately guided busbars. The insulation sleeve is designed to counteract and efficiently compensate for any spatial divergence between the busbar connection points. This eliminates the need for direct contact between the busbars, thus simplifying their geometric and structural design.

[0011] For the purposes of this patent application, an inverter assembly in the context of electric drive systems of motor vehicles serves to convert direct current into alternating current in order to power an electric machine. The inverter assembly is thus a part of the electric drive train that enables control of the motor power and speed through precise control of the phase currents.

[0012] The inverter assembly preferably consists of power electronics modules containing high-power semiconductors such as IGBTs (Insulated-Gate Bipolar Transistors) or MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors). The inverter assembly may also include control circuits that drive the semiconductor elements. These circuits then generate the necessary control signals to produce alternating current at the desired frequency and phase. Furthermore, the inverter assembly may be equipped with a range of protection circuits that monitor for overloads, short circuits, and other fault conditions, thus protecting the assembly and connected components from damage.

[0013] Advantageously, the inverter assembly also includes an interface to the vehicle management system, which regulates the power output based on driver input and other vehicle parameters. This integration enables dynamic adaptation to driving conditions such as acceleration, load changes, and speed control.

[0014] In this design, the inverter assembly can be housed in an inverter enclosure to ensure electrical safety and minimize electromagnetic interference. The enclosure also protects the electronic components from environmental influences such as moisture, dust, and temperature fluctuations.

[0015] The inverter housing is preferably made of a metallic material, particularly preferably aluminum, gray cast iron, or cast steel, and is formed by a primary forming process such as casting or die casting. The inverter housing is particularly preferably cup-shaped. In this context, it is especially preferred that the housing cover can be inserted into the cup-shaped inverter housing. Alternatively, it would also be conceivable that the housing cover rests on the cup-shaped inverter housing and covers its opening. The inverter housing can also be part of the motor housing of the electric machine, or vice versa. This means that the inverter housing is formed wholly or partially as a single piece, particularly monolithically, with the motor housing of the electric machine.The power electronics housed in the inverter casing can be used, in particular, for an electric machine of an electrically operated drivetrain of a motor vehicle. The power electronics are preferably a combination of various components that control or regulate a current to the electric machine of the axle drivetrain, preferably including the necessary peripheral components such as cooling elements or power supplies. In particular, the power electronics contain one or more power electronic components configured to control or regulate a current. The power electronics particularly preferably have more than two, and more preferably three, separate phases or current paths, each with at least one dedicated power electronic component.The power electronics are preferably designed to control or regulate a power output per phase with a peak power, preferably continuous power, of at least 10 W, preferably at least 100 W, and particularly preferably at least 1000 W.

[0016] For the purposes of this patent application, an EMC filter assembly is a component within the electrical power supply unit designed to filter and minimize electromagnetic interference and to ensure electromagnetic compatibility (EMC) between different electronic systems and components in the vehicle.

[0017] The EMC filter assembly preferably and advantageously consists of an arrangement of filter elements such as inductors, capacitors, and resistors that work together to attenuate interference on the power supply and signal lines. These components are configured to attenuate unwanted high-frequency signal components, thereby ensuring the integrity of the vehicle's electrical and electronic systems. The filter design can, for example, be based on the use of LC circuits (inductance-capacitor circuits), which are advantageously designed to comply with industry-specific EMC standards and requirements. The EMC filter assembly can further include specialized components that provide protection against transient overvoltage events, such as varistors or surge arresters.Ferrite cores or shielded housings can also be used to further reduce electromagnetic emissions.

[0018] Advantageously, the EMC filter assembly is integrated into the overall design of the electrical machine in such a way that it is easily accessible and maintainable. This simplifies necessary replacement work on the filter elements should they need to be replaced due to their limited lifespan or damage. The EMC filter assembly is preferably housed in a robust enclosure designed to provide effective shielding against stray electromagnetic fields. This enclosure can also ensure physical separation from other assemblies to minimize mutual interference.

[0019] Within electric vehicles, the voltages applied to the EMC filter assembly can range from 200 volts to 1,000 volts, depending on the specific vehicle design and power level, particularly in high-voltage drive systems. The current that can flow through the EMC filter assembly depends on the capacity of the electric drive and the energy storage system. These currents range from a few tens of amperes for auxiliary drives and smaller vehicles to several hundred amperes for high-performance vehicles and vehicles with large battery capacities, especially during peak load situations such as fast charging or acceleration. For example, in a typical electric vehicle with a nominal battery voltage of approximately 400 volts, currents ranging from 100 amperes to several hundred amperes could flow in a high-current scenario, such as during fast charging or maximum acceleration.For a vehicle with a high-voltage battery, such as 800 volts, the currents may be somewhat lower under similar operating conditions, since a lower current is required for the same power output at a higher voltage. An important aspect here is that the EMC filter assembly must be designed to safely handle these current and voltage values ​​without compromising the electromagnetic compatibility of the system.

[0020] For the purposes of this patent application, an insulating sleeve is a component specifically designed to electrically connect two electrical conductors while simultaneously providing electrical insulation from their surroundings. The insulating sleeve serves for the electrical insulation and mechanical fixing of busbars or other electrical contacts within the electrical system of a motor vehicle. The insulating sleeve preferably consists of a cylindrical annular conductor element designed to be suitable for use in high-voltage applications with regard to its electrical conductivity. The conductor element primarily serves to enable an electrical connection between two busbars and simultaneously provide defined mechanical support for the enclosed conductor element.The current-conducting element is preferably made of a metal material with high electrical conductivity, such as copper or aluminum, to ensure minimal resistance increase in the connection and to enable effective current transfer between the busbars. This current-conducting element is enclosed in a cylindrical shell made of an electrically insulating material, thus providing electrical insulation of the insulating sleeve from the environment.

[0021] The insulating sleeve is further supplemented by fastening means, which may be designed using screws, bolts, or other suitable mechanical connecting elements. These fastening means preferably penetrate the current-conducting element in such a way that the busbars are clamped together and secured in their relative position.

[0022] Advantageously, the inner surface of the cylindrical shell is designed to provide a secure fit for the associated current-conducting element. The cylindrical shell can incorporate design features such as recesses or raised areas that correspond to the current-conducting element to create a positive-locking connection. This simplifies assembly and ensures reliable positioning throughout the connection's service life. Furthermore, the outer surface of the cylindrical shell can feature additional components for connection to other parts of the current-conducting device, such as threads for bolted connections, grooves for snap-fit ​​or sliding connections, or flanges for bolted or welded connections. These features contribute to simplified and secure assembly of the cylindrical shell and enable robust integration into the surrounding mechanical structural components.

[0023] For the purposes of this patent application, the electrically insulating cylindrical shell is a component that is used inside the insulating sleeve for the purpose of electrical insulation. It is designed in such a way that it prevents or at least restricts the electrical conductivity of the insulating sleeve at its outer surface and thus prevents an electric current flow between these components.

[0024] The cylindrical shell is preferably made of an electrically insulating material, such as a high-performance plastic or a ceramic material, which, due to its properties, is able to withstand the opposing electrical voltages and ensure reliable insulation over long periods of time, even under difficult operating conditions such as high temperatures, humidity or mechanical stresses.

[0025] The electrical conductor can also be designed with interlocking features for connection to the cylindrical shell, such as radial projections, notches, or grooves that interact with corresponding structures on the cylindrical shell, thus enabling secure and slip-resistant mounting. Furthermore, the electrical conductor can also perform additional functions, such as thermal insulation or flame-retardant properties, to further enhance the safety of the electrical device and ensure compliance with relevant safety regulations and standards.

[0026] In the context of this invention, a fastening element is an element that serves to securely and permanently fix the components of the power supply device, in particular the busbars and insulation sleeves, in their relative position to one another. The fastening element contributes to ensuring a mechanically stable and electrically conductive connection between the components concerned and to protecting them from external influences or internal stresses.

[0027] The fastener is preferably made of a material exhibiting high strength and resistance to mechanical stress, corrosion, and temperature fluctuations, such as stainless steel or another durable metal. Structurally, it may be a screw, bolt, rivet, or other mechanical connecting element specifically designed for use in electrical power supply systems of vehicles.

[0028] The fastener may have a head that, when tightened, contacts the busbar, thus establishing a secure electrical contact. The fastener may also have a mating element, such as a nut or washer, which is placed on the opposite side of the fastener and serves to compress the components together and ensure a secure fit.

[0029] For the purposes of this patent application, a busbar is an electrical conductor component used to transmit electrical current between different components of an electrical power supply unit, such as the inverter assembly and the EMC filter assembly within the electric powertrain of a motor vehicle. The busbar is designed to safely and reliably conduct the currents necessary for the operation of the motor.

[0030] The busbar is preferably made of a conductive metal with high electrical conductivity, such as copper or aluminum, which enables current transmission with minimal resistive losses. The geometric shape of the busbar is designed to meet the specific requirements of electrical current flow, heat dissipation, and mechanical stress that occur during the operation of the electric drive. The busbars particularly preferably have a substantially rectangular cross-section. Advantageously, the surface of the busbar is treated or coated to ensure corrosion resistance and maintain electrical conductivity over a long period. Common finishing processes can include tinning or the application of silver or nickel layers, which possess both protective and conductivity-enhancing properties.

[0031] The design of the busbar also takes into account the requirements for simple and safe installation by precisely defining the contact areas for connection with other components, such as the insulation sleeves. This can be achieved through special shaping or by adding mounting holes and slots to ensure a secure and durable mechanical connection.

[0032] For the purposes of this patent application, a partition is a structural component within a power supply unit that serves to physically separate the EMC filter assembly and the inverter assembly in order to minimize mutual electromagnetic interference. Suitable materials for the partition include, for example, metals or special EMC-shielding composite materials. Advantageously, the partition has openings or feedthroughs for the insulation sleeves, enabling the necessary spatial connection between the assemblies without compromising the EMC protection function. These feedthroughs are designed to ensure precise alignment and sealing of the elements passing through them, particularly the insulation sleeves, to guarantee the continuity of the shielding effect.

[0033] According to an advantageous embodiment of the invention, the busbar pairs can be arranged to run essentially parallel to each other in the connection area. This leads to optimized space utilization within the drive train's installation space and promotes simplified, error-minimized assembly. In this context, it is further preferred that the busbar pairs are essentially identical in the connection area, which simplifies manufacturing processes and reduces production costs. A standardized component design also simplifies warehousing and logistics and contributes to reducing assembly errors, as assembly workers do not have to pay attention to different component variants. The interchangeability of these parts further reduces maintenance costs and improves spare parts availability.

[0034] It is also advantageous that all busbars in the connection area are essentially identical in shape, which allows for high compatibility and interchangeability of the connection components.

[0035] According to a further preferred development of the invention, it can also be provided that the fastening means run essentially parallel to each other with respect to their longitudinal extent, which helps to ensure a uniform force distribution during the assembly and clamping of the contact points.

[0036] Furthermore, according to another advantageous embodiment of the invention, the insulating sleeves can be designed to be essentially identical. The homogeneous design of the insulating sleeves represents a further advantage for manufacturing and standardization. A uniform component design not only ensures lower production costs through economies of scale, but also simplifies logistics and warehousing. Moreover, the use of identical components accelerates assembly and reduces potential sources of error.

[0037] It can be provided that the cylindrical shell and the current-conducting element are positively connected to one another. According to a further advantageous embodiment of the invention, it is also advantageous if the cylindrical shell has at least one radially inwardly projecting positive locking element on its inner surface that engages with a corresponding radially inwardly projecting positive locking element on the outer surface of the current-conducting element, or if the cylindrical shell has at least one radially outwardly projecting positive locking element on its inner surface that engages with a corresponding radially outwardly projecting positive locking element on the outer surface of the current-conducting element. The configuration of the cylindrical shells with positive locking elements that engage with corresponding positive locking elements of the current-conducting element enables a precise and robust mechanical connection of the two components.Such a connection helps to minimize manufacturing tolerances and ensures durable, resistant insulation against mechanical stress. Furthermore, the adaptation of the positive locking devices contributes to faster assembly and a reduction in assembly errors.

[0038] It is also conceivable that the cylindrical shell and the electrical conductor are connected to each other by means of a force-fit connection. Press fits are particularly preferred in this context.

[0039] Furthermore, it would be possible to connect the cylindrical shell and the conductive element using a form-fit connection. Adhesive bonds or welded joints could be used for this purpose. Additionally, the conductive element could be overmolded with plastic, for example, using an injection molding process.

[0040] According to a further particularly preferred embodiment of the invention, the insulating sleeves may extend through a housing component of the inverter assembly and / or a housing component of the EMC filter assembly, thus enabling stable mechanical anchoring and precise positioning of the insulating sleeves. This design can also contribute to improved sealing and protection against environmental influences, and enhances EMC performance through a clear spatial separation of electromagnetic field sources.

[0041] The housing component of the EMC filter assembly and the housing component of the inverter assembly are formed in one piece, particularly monolithically, with a partition wall between the EMC filter assembly and the inverter assembly, and the insulating sleeves extending through this partition wall. This partition wall can be part of either the housing component of the EMC filter assembly or the housing component of the inverter assembly. The partition wall is present, in particular, if the housing components are at least partially monolithic and the partition wall then forms the structural interface between the housing components.

[0042] According to the invention, the fastening means extend with play through each of the cylindrical ring-shaped current-conducting elements, thereby offering the advantage of accommodating tolerances due to thermal expansion or other physical influences, thus reducing the mechanical stress on the current-conducting element. Furthermore, positional and positioning tolerances can also be compensated for in this way.

[0043] In another preferred embodiment of the invention, it can also be provided that the outer diameter of the cylindrical shell corresponds to between 0.8 and 1.2 times the width of the busbars in the connection area, thereby achieving a balanced compromise between mechanical stability, electrical conductivity and insulation characteristics.

[0044] Furthermore, it is advantageous if the wall thickness of the cylindrical shell and the wall thickness of the cylindrical annular current-conducting element have a ratio of 1:3-1:10, which also contributes to a balanced compromise between mechanical stability, electrical conductivity and insulation characteristics.

[0045] It is further preferred that the current-conducting element be made of copper. The use of copper for the manufacture of the current-conducting element offers technical advantages with regard to electrical conductivity and thermal properties, as copper exhibits outstanding electrical conductivity and good thermal conductivity. This leads to improved energy transfer and can contribute to cooling the conductors, particularly in high-power applications such as in the automotive sector.

[0046] According to a further preferred embodiment of the invention, it can be advantageous if the cylindrical shell is formed from an electrically insulating plastic, which offers the technical advantage of good electrical insulation and cost-effective manufacturability.

[0047] It can also be advantageous to further develop the invention such that the fastening means are each designed as a screw with a screw head resting on one of the busbars, which can provide an easy-to-use and robust connection method. The use of screws allows the contacts to be precisely adjusted and easily loosened if necessary, which has a positive effect on assembly and maintenance effort.

[0048] In this context, it can also be advantageous for a nut to engage with the screw at the end opposite the screw head, and for the nut to rest against one of the busbars. This prevents the connection from loosening under vibration, which is particularly important in vehicle operation. Furthermore, it can be advantageous for the nuts to be fixed within a housing component of the inverter assembly, ensuring a stable and reliable connection. The fixed position of the nuts also increases assembly precision and reduces the risk of losing components during assembly or maintenance.

[0049] The insulating sleeves are each housed in a plastic carrier, which is fixed to a housing component of the inverter assembly, a housing component of the EMC filter assembly, or the partition. Integrating the plastic carrier into the housing components allows for a spatially defined arrangement and creates better conditions for EMC protection measures through the physical separation of electromagnetic fields.

[0050] For the purposes of this patent application, a plastic carrier is a component made of a polymeric material that serves to structure, position, and secure other components within an electrical supply system. Its primary function is, in particular, to accommodate and support components such as insulation sleeves and to ensure their precise position within the overall system. The plastic carrier is preferably made of an insulating plastic material. Advantageously, the plastic carrier is designed to precisely accommodate and fix the insulation sleeves, thus ensuring a secure and permanent hold. The shape of the plastic carrier can be designed according to the geometric requirements of the insulation sleeves.The plastic carrier can also be provided with mounting points that allow for easy installation on the inverter assembly, the EMC filter assembly, the partition, or other areas of the electrical power supply unit. These mounting points can be designed as snap-fit, detent, or screw connections to facilitate tool-free assembly or to provide a secure bolted connection. Preferably, the plastic carrier incorporates design features that promote easy and error-free assembly, such as guide grooves, positioning lugs, or color coding. The selection of these design features aims to reduce assembly time, minimize assembly errors, and facilitate maintenance or component replacement.

[0051] In this context, it can also be advantageous if the plastic carriers of the insulation sleeves are formed in one piece, particularly monolithically. This offers the benefit of reduced assembly effort due to the absence of secondary connection or assembly steps. A one-piece design can also reduce manufacturing costs and improve the structural integrity of the plastic carriers. It is further preferred that the plastic carriers are made of an electrically non-conductive plastic, which helps to ensure continued electrical insulation and provides additional protection against unintended current paths. This eliminates a potential risk of electromagnetic interference, which is important for EMC-critical applications.Therefore, it is highly preferred if the outer surface of the cylindrical shells is at least partially, preferably completely, covered by the plastic carrier, which contributes to the mechanical protection of the cylindrical shells and improves the electrical insulation.

[0052] It would also be conceivable that one or more of the plastic carriers are formed in one piece, especially monolithically, with the cylindrical shell.

[0053] Finally, the invention can also advantageously be implemented such that the plastic carriers are fixed to a housing component of the inverter assembly, a housing component of the EMC filter assembly, or the partition by means of a positive-locking connection. This connection provides a durable and vibration-resistant solution that simultaneously enables quick and error-free assembly, for example, through easily identifiable and snap-in connecting elements. In this context, it is further preferred that the positive-locking connection has snap hooks, thus enabling tool-free assembly that can be carried out quickly, safely, and without special knowledge or skills. This reduces assembly costs and shortens assembly times. Furthermore, snap hooks offer additional security against loosening of the connection when used in environments subject to vibrations and movements, such as those common in vehicles.

[0054] The invention will now be explained in more detail with reference to figures, without limiting the general concept of the invention.

[0055] It shows: Fig. 1 an electric machine with a current supply device in a perspective view, Fig. 2 a detailed view of the connection area between the EMC filter assembly and the inverter assembly of the power supply unit in a perspective sectional view, Fig. 3 an insulation sleeve in a perspective exterior view and a perspective longitudinal section view, Fig. 4 A detailed view of the connection area between the EMC filter assembly and the inverter assembly of the power supply unit with insulating sleeves mounted in a plastic carrier in a perspective sectional view, Fig. 5 a plastic support in a perspective view, Fig. 6. A plastic support inserted in a partition wall in a form-fitting manner, shown in a perspective sectional view. Fig. 7 a motor vehicle with an electrical power supply device for an electric machine of an electrically operated drive train in a schematic representation.

[0056] The Fig. Figure 1 shows an electrical power supply device 1 for an electric machine 2 of an electrically operated drive train 3 of a motor vehicle 4, as exemplified in the Fig. 7 is outlined. In the Fig. 7 The electric machine 2 and a gear arrangement 31 form a structural unit, which is also referred to as an e-axle.

[0057] It is clearly visible that the inverter assembly 5 and the EMC filter assembly 7 are arranged in two separate chambers of the motor housing of an electric machine 2, which are open in the illustrated embodiment, allowing a view into their interior. The inverter assembly 5 is located in the upper housing component 18 in the figure, while the EMC filter assembly 7 is spatially separated from it and housed in the side housing component 19. The electrical circuit boards of the assemblies 5 and 7 are approximately perpendicular to each other. In the illustrated embodiment, the housing components 18 and 19 are monolithic with the motor housing of the electric machine 2 and separated from each other by a common partition 24, as can be seen from the overall view of the Fig. 1 with the Fig. 2 opens up.

[0058] In the illustrated embodiment, the EMC filter assembly 7 is an assembly that can also be used in other electrical machines besides the one shown in the Fig. The electric machine shown in Figure 1 is used. Accordingly, the geometry of the busbars 22, 23 of the busbar pair 8 of this EMC filter assembly 7 can only be adapted to different installation space situations to a very limited extent. The inverter assembly 5 also originates from an assembly that is used in electric machines other than the one shown in Figure 1. Fig. The one shown in Figure 1 is used. Consequently, geometric changes to the busbars 20, 21 of the busbar pair 6 of the inverter assembly 5 are not freely implementable here either.

[0059] The power supply unit 1 now comprises – as can be clearly seen from the Fig. 2 can be seen - the inverter assembly 5 with the first busbar pair 6 and the EMC filter assembly 7 with the second busbar pair 8, wherein the busbar pairs 6,8 have a connection area 9 in which a busbar 20,21 of the first busbar pair 6 is electrically connected to a busbar 22,23 of the second busbar pair 8 via an electrical contacting means 10.

[0060] The electrical contacting means 10 each comprise an insulating sleeve 11, each formed from a cylindrical ring-shaped current-conducting element 13 received in an electrically insulating cylindrical shell 12, and each arranged between one of the busbars 20, 21 of the first busbar pair 6 and one of the busbars 22, 23 of the second busbar pair 8 such that one of the current-conducting elements 13 is electrically conductively in contact with one of the busbars 20, 21 of the first busbar pair 6 and with one of the busbars 22, 23 of the second busbar pair 8. The current-conducting element 13 is penetrated by a fastening means 14, by means of which one of the busbars 20, 21 of the first busbar pair 6 and one of the busbars 22, 23 of the second busbar pair 8 are clamped together along the longitudinal extension 15 of the insulating sleeve 11.

[0061] The insulating sleeve 11 allows the spatial offset of the contact surfaces between the busbar pairs 6,8 of the EMC filter assembly 7 and the inverter assembly 5 to be overcome.

[0062] The busbar pairs 6, 8 run essentially parallel to each other in the connection area 9 and are essentially identical in design. The fastening means 14 also run essentially parallel to each other with respect to their longitudinal extent, with each fastening means 14 passing through one of the cylindrical ring-shaped current-conducting elements 13 with some play in its opening 29.

[0063] One can recognize from the Fig. 2. It is also good that the insulating sleeves 11 are essentially identical in design. The current-conducting element 13 is pressed into the cylindrical shell 12, the cylindrical shell 12 having at least one radially inwardly projecting positive locking element on its inner surface, which engages in a corresponding radially inwardly projecting positive locking element on the outer surface of the current-conducting element 13, which is well represented by the Fig. 3. Alternatively, it would also be possible for the cylindrical shell 12 to have at least one radially outwardly projecting positive locking element on its inner surface, which engages in a corresponding radially outwardly projecting positive locking element on the outer surface of the current-conducting element 13. However, this is not shown in the figures. In the illustrated embodiment, the cylindrical shell 12 is made of an electrically insulating plastic and the current-conducting element 13 is made of copper. The opening 29 is dimensioned such that the screw 16 has some play in it, thus ensuring tolerance compensation between the busbars.

[0064] As briefly mentioned at the beginning, the housing component 19 of the EMC filter assembly 7 and the housing component 18 of the inverter assembly 5 are formed together in one piece, in particular monolithically, wherein a partition 24 is formed between the EMC filter assembly 7 and the inverter assembly 5 and the insulation sleeves 11 extend through the partition 24.

[0065] The fastening elements 14 are each designed as a screw 16 with a screw head 17 resting on one of the busbars 20, 21, 22, 23. At the end of the screw 16 opposite the screw head 17, a nut 30 engages with the screw 16 and rests against one of the busbars 20, 21, thus enabling the screw connection to be secured. The nuts 30 are fixed in a housing component 18 of the inverter assembly 5.

[0066] In the Fig. Figure 4 shows a further embodiment of the invention, in which the insulating sleeves 11 are each received in a plastic carrier 25, which is fixed to the partition 24. When an insulating sleeve 11 is inserted, the outer surface of the cylindrical shell 12 is completely covered by the plastic carrier 25. In this embodiment, the plastic carriers 25 of the insulating sleeves 11 are monolithically formed from a single plastic, which is particularly evident from the detailed illustration of the Fig. 5 can be seen. The plastic carriers 25 are made of an electrically non-conductive plastic. Each of the plastic carriers 25 has a receiving cylinder 26 in which an insulating sleeve 11 can be inserted. The receiving cylinders 26 are spaced apart from each other by the retaining plate 28, the plane of extension of the retaining plate 28 being essentially perpendicular to the longitudinal extension of the receiving cylinders 26. Two snap hooks 27 extend from the retaining plate in the longitudinal direction of the receiving cylinders 26. As can be seen in the Fig. 6 detects, the snap hooks 27 engage behind the partition 24 and thus secure the retaining plate 28 against unwanted loosening.

[0067] The invention is not limited to the embodiments illustrated in the figures. The foregoing description is therefore not to be considered limiting, but rather explanatory. The following claims are to be understood as meaning that a named feature is present in at least one embodiment of the invention. This does not preclude the presence of further features. Insofar as the claims and the foregoing description define 'first' and 'second' features, this designation serves to distinguish between two similar features without establishing any hierarchy. Reference symbol list 1 Power supply unit 2 electric machine 3 Powertrain 4 Motor vehicle 5 Inverter assembly 6 pairs of busbars 7 EMC filter assembly 8 pairs of busbars 9 Connection area 10 contact materials 11 Insulation sleeve 12 cylindrical shell 13 Conductive element 14 Fasteners 15 Longitudinal extent 16 screws 17 screw head 18 Housing component 19 Housing component 20 busbar 21 busbar 22 busbar 23 busbar 24 partition wall 25 plastic carriers 26 receiving cylinders 27 snap hooks 28 Mounting plate 29 Opening 30 mother 31 Gear arrangement

Claims

[1] Electrical power supply unit (1) for an electric machine (2) of an electrically operated drive train (3) of a motor vehicle (4), comprising an inverter assembly (5) with a first busbar pair (6) and an EMC filter assembly (7) with a second busbar pair (8), wherein the busbar pairs (6, 8) have a connection area (9) in which a busbar (20, 21) of the first busbar pair (6) is electrically connected to a busbar (22, 23) of the second busbar pair (8) via an electrical contacting means (10), where The electrical contacting means (10) each comprise an insulating sleeve (11), each of which is formed from a cylindrical ring-shaped current-conducting element (13) received in an electrically insulating cylindrical shell (12) and which are each arranged between one of the busbars (20, 21) of the first busbar pair (6) and one of the busbars (22, 23) of the second busbar pair (8) such that one of the current-conducting elements (13) is electrically conductively in contact with one of the busbars (20, 21) of the first busbar pair (6) and with one of the busbars (22, 23) of the second busbar pair (8) and the current-conducting element (13) is penetrated by a fastening means (14) by means of which one of the busbars (20, 21) of the first busbar pair (6) and one of the busbars (22, 23) of the second busbar pair (8) are brought towards each other in the longitudinal extension (15) of the insulating sleeve (11). are tense characterized by , that the fastening means (14) each extend with play through one of the cylindrical ring-shaped current-conducting elements (13). [2] Electrical power supply device (1) for an electric machine (2) of an electrically operated drive train (3) of a motor vehicle (4), comprising an inverter assembly (5) with a first busbar pair (6) and an EMC filter assembly (7) with a second busbar pair (8), wherein the busbar pairs (6, 8) have a connection area (9) in which a busbar (20, 21) of the first busbar pair (6) is electrically connected to a busbar (22, 23) of the second busbar pair (8) via an electrical contacting means (10), where The electrical contacting means (10) each comprise an insulating sleeve (11), each of which is formed from a cylindrical ring-shaped current-conducting element (13) received in an electrically insulating cylindrical shell (12) and which are each arranged between one of the busbars (20, 21) of the first busbar pair (6) and one of the busbars (22, 23) of the second busbar pair (8) such that one of the current-conducting elements (13) is electrically conductively in contact with one of the busbars (20, 21) of the first busbar pair (6) and with one of the busbars (22, 23) of the second busbar pair (8) and the current-conducting element (13) is penetrated by a fastening means (14) by means of which one of the busbars (20, 21) of the first busbar pair (6) and one of the busbars (22, 23) of the second busbar pair (8) are brought towards each other in the longitudinal extension (15) of the insulating sleeve (11). are tense characterized by , that the insulation sleeves (11) are each received in a plastic carrier (25), which is fixed to a housing component (18) of the inverter assembly (5) or a housing component (19) of the EMC filter assembly (7) or the partition (24). [3] Power supply device (1) according to claim 1 or 2, characterized by that the busbar pairs (6,8) run essentially parallel to each other in the connection area (9). [4] Power supply device (1) according to any one of the preceding claims, characterized by , that the fastening means (14) run substantially parallel to each other with respect to their longitudinal extent. [5] Power supply device (1) according to any one of the preceding claims, characterized by that the insulating sleeves (11) are essentially identical in design. [6] Power supply device (1) according to any one of the preceding claims, characterized bythat the insulating sleeves (11) penetrate a housing component (18) of the inverter assembly (5) and / or a housing component (19) of the EMC filter assembly (7). [7] Power supply device (1) according to any one of the preceding claims, characterized by , that the outer diameter of the cylindrical shell (12) corresponds to between 0.8-1.2 times the width of the busbars (20,21,22,23) in the connection area (9). [8] Power supply device (1) according to any one of the preceding claims, characterized by , that the fastening means (14) are each designed as a screw (16) with a screw head (17) resting on one of the busbars (20,21,22,23). [9] Power supply device (1) according to claim 2, characterized by , that the plastic carriers (25) are fixed to a housing component (18) of the inverter assembly (5) or a housing component (19) of the EMC filter assembly (7) or the partition (24) by means of a positive locking connection.

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