System for connecting electrical connections

Abstract

System (1) for connecting electrical connections, comprising - a device (2) for supplying voltage to a power module (5) with at least one electrical connection (3), the power module (5) having a top side (5a) and a bottom side (5b), - a heat sink (6) and - at least one electrical connection (4) of a component to be supplied with an electrical voltage, where - the at least one electrical connection (3) of the device (2) is formed on a first side surface (2a) of the device (2) and the at least one electrical connection (4) of the component to be supplied with electrical voltage is formed in a region of a side surface (2b, 2c, 2d) of the device (2) that deviates from the first side surface (2a), - the connections (3, 4) are each connected to one another via an electrically conductive connecting element (9, 10) and - the underside (5b) of the power module (5) is arranged adjacent to an upper side (6a) of the heat sink (6), wherein in the region of the support of the underside (5b) of the power module (5) and the upper side (6a) of the heat sink (6), at least one recess (12) is formed, which is formed in a surface of the upper side (6a) of the heat sink (6) as a groove open on one side and extends from the first side surface (2a) to a side surface (2b, 2c, 2d) of the device (2) different from the first side surface (2a) through the device (2), wherein the open side of the recess (12) formed as a groove is closed off by the underside (5b) of the power module (5) and at least one electrically conductive connecting element (9) is arranged within the at least one recess (12).

Description

[0001] The invention relates to a system for connecting electrical connections. The system comprises a voltage supply device comprising a power module with at least one electrical connection, a heat sink, and at least one electrical connection of a component to be supplied with an electrical voltage. The electrical connections are each connected to one another via an electrically conductive connecting element.

[0002] When installing electrical components, especially for high-current applications with currents greater than 10 A, busbars are often used to electrically connect individual assemblies.

[0003] For example, it is known from the prior art to use inverters with prefabricated power modules for converting direct voltage into alternating voltage or for converting direct current into alternating current. The inverter and the power module are designed as a single, integrated unit for supplying power, with the power module being arranged on a housing of the inverter.

[0004] The power supply device, in particular the power module, has control terminals for controlling the device, as well as high-current terminals for connecting to a voltage source for the DC voltage supply, and terminals designed as outputs for tapping the AC voltage. The use of busbars offers a simple, inexpensive, and therefore preferred option for electrically connecting the high-current terminals to an electrical circuit and / or to connectors of a neighboring electrical system.

[0005] The high-current terminals of the voltage supply device, in particular the terminals designed as outputs for tapping the AC voltage, for example, the terminals for connecting the device to terminals of an electric motor, are conventionally arranged next to one another at a distance from one another and on a common side of the device. If the electrical terminals of the component to be supplied with voltage, for example, the terminals of the electric motor, are randomly distributed around the device, the terminals of the device can only be connected to the terminals of the component to be supplied with AC voltage via busbars with considerable effort.

[0006] Furthermore, it is known from the prior art to attach the power module with a bottom side to a top side of the inverter housing or a heat sink. Both the inverter housing and the heat sink serve as a heat sink for dissipating heat emitted by the power module.

[0007] The high-current terminals are traditionally located on the top side of the power module of the power supply device. Since a printed circuit board (PCB) is also located in the area of the top side of the power module, i.e., above the high-current terminals, the device's high-current terminals are very difficult to access, which further increases the complexity of connecting the terminals of the component to be supplied with power via busbars.

[0008] EP 0 830 811 B1 describes a heat sink with an integrated busbar for electrically connecting a plurality of power modules of a printed circuit board arrangement. The printed circuit board arrangement has two circuit boards aligned parallel to one another, each with a front surface and a rear surface. The power modules are arranged on the surfaces of the circuit boards. The printed circuit board arrangement is also designed with a plug-in strip provided between the circuit boards, which is arranged on the rear surface of a first circuit board and is connected to power modules fixed to the first circuit board as well as to a second circuit board. The heat sink, which is intended to absorb heat from the power modules and is arranged between the circuit boards and adjacent to the plug-in strip, has a front surface and a rear surface.On the front surface of the heat sink, a cover is formed with openings for receiving electrical connections, which extend between the header and the power modules so that the header is electrically connected to the power modules.

[0009] DE 11 2010 002 702 T5 discloses a heat sink for a drive device with a heat transfer surface arranged at a distance from a surface of a motor housing in an axial direction. A power module has a potting part and is placed on the heat transfer surface of the heat sink. Motor cables extend from the motor housing and are electrically connected to the power module and winding wires.

[0010] DE 102 32 566 B4 discloses a semiconductor component comprising a housing formed from a metal base for heat radiation, an encapsulating housing formed in one piece with terminals, into which external connecting conductors of a main circuit are cast, a power circuit and a control circuit which are cast in the housing by means of a gel-like, injected filler.

[0011] From the Fig. 1a and Fig. 1b shows a system 1' for connecting electrical connections 3 of a device 2 for supplying voltage and electrical connections 4 of a consumer (not shown), such as an electric motor, from the prior art. Fig. 1a shows the system 1' in a top view, while the system 1' in Fig. 1b is shown in a side view.

[0012] A power module 5 is arranged with a bottom side 5b attached to a heat sink 6, for example, to a top side 6a of a housing of an inverter or a heat sink. The connections 3 of the device 2, in particular the high-current connections of the power module 5, are designed as components for connecting the power module 5 to the load on a top side 5a of the power module 5 of the device 2. The top side 5a and the bottom side 5b are arranged as opposite, mutually facing sides of the power module 5.

[0013] The top side 5a of the power module 5 and thus of the device 2 is covered with a printed circuit board 7, which extends substantially over the entire top side 5a of the power module 5. The Fig. 1a, not shown, is arranged at a distance from the top side 5a of the power module 5 of the device 2 via signal pins 8, which also serve as holding elements.

[0014] The terminals 4 of the component to be supplied with voltage, i.e., the consumer, are each formed in the region of different side surfaces 2a, 2b of the device 2, while the terminals 3 of the device 2 for tapping the alternating voltage are arranged on a common side surface 2a of the device 2. Accordingly, not all of the terminals 3, 4 of a pair of terminals 3, 4 to be connected to one another are arranged opposite one another and adjacent to one another at short distances. Rather, at least the terminals 3, 4 of one or more pairs of terminals 3, 4 are not arranged opposite one another and are arranged at greater distances from one another.

[0015] The electrical connections 3 of the device 2 for supplying voltage and the electrical connections 4 of the consumer (not shown) are electrically connected to one another, in particular in pairs, via electrical connecting elements 9', 10 designed as busbars. Due to the arrangement of the connections 3 on a common side surface 2a of the device 2 and the arrangement of the connections 4 of the component to be supplied with voltage on different side surfaces 2a, 2b of the device 2, the busbars 9' of the device 2, in particular the heat sink 6, can be arranged directly. The busbars 9' thus connect connections 3, which are arranged on the first side surface 2a of the device 2, with connections 4 of the consumer, which are arranged in the region of the second side surface 2b of the device 2. Depending on the arrangement of the connections 3, 4 relative to one another, at least one busbar 9' runs, in the embodiment according to the Fig. 1a and Fig. 1b, two busbars 9' run along a third side surface 2c and a fourth side surface 2d, respectively, and spaced from the side surface 2c, 2d around the device 2 at least partially.

[0016] The terminals 3 of the device 2 are arranged protruding from the circuit board 7 or projecting beyond the circuit board 7. The busbar 9' is soldered adjacent to the terminal 3 to a conductor track 11 formed on the circuit board 7, which extends to the terminal 3. The conductor track 11 thus establishes an electrical connection between the busbar 9' and the terminal 3. Alternatively, the circuit board 7, which is arranged at a distance from the top side 5a of the power module 5, can also be arranged at a distance from the terminals 3 of the device 2, at least partially covering the terminals 3.

[0017] The design of the busbars 9' as an electrical connection of the terminals 3, 4, which extend at least partially around the device 2, requires very complex shapes and great lengths of the busbars 9' and thus a large installation space for the device 2. The busbars 9' cause high costs in production and assembly and also have a very strong influence on the electromagnetic compatibility behavior of the device 2.

[0018] Electromagnetic compatibility refers to the ability of a system to not interfere with the functions of other systems through electrical or electromagnetic effects, or to not be interfered with by other systems in their own function. Electromagnetic compatibility specifically means the absence of influences on other systems that could lead to malfunctions of electrical or electronic equipment, for example, through electrical, magnetic, or electromagnetic fields and processes.

[0019] The object of the present invention is to improve the device for connecting electrical connections such that the electrical connections of the voltage supply device and the electrical connections of the component to be supplied with voltage are connected to one another over the shortest possible distances. The busbars to be used as electrical connecting elements should be designed with simple shapes and minimal lengths. The device should have a small installation space. The costs of manufacturing and assembling the busbars and the device should be minimized. The electromagnetic compatibility of the device should be optimal.

[0020] The problem is solved by the subject matter having the features of the independent patent claims. Further developments are specified in the dependent patent claims.

[0021] This object is achieved by a system according to the invention for connecting electrical connections. The system comprises a voltage supply device comprising a power module with at least one electrical connection, a heat sink, and at least one electrical connection of a component to be supplied with an electrical voltage. The power module is configured with a top side and a bottom side, with the bottom side of the power module being arranged adjacent to a top side of the heat sink. The power module and the heat sink are advantageously thermally contacted with one another, with the power module and the heat sink being thermally conductively connected to one another.

[0022] The electrical connections of the voltage supply device and the component to be supplied with an electrical voltage are each connected to one another via an electrically conductive connecting element.

[0023] According to the concept of the invention, at least one recess is formed in the region where the underside of the power module and the top side of the heat sink rest, extending through the device from a first side surface to a side surface of the device that is different from the first side surface. According to the invention, at least one electrically conductive connecting element is arranged within the at least one recess.

[0024] The electrically conductive connecting element preferably protrudes from at least one end face of the recess for connection to at least one of the electrical connections.

[0025] According to an advantageous embodiment of the invention, the at least one electrically conductive connecting element is designed as a busbar. The number of busbars depends on the number of terminals of the power module to be electrically connected and the component to be supplied with electrical voltage.

[0026] According to the invention, the at least one recess for receiving the at least one electrically conductive connecting element is formed in a surface of the upper side of the heat sink as a groove open on one side. The open side of the groove is closed by the underside of the power module. The groove advantageously has a rectangular, in particular a square, cross-section.

[0027] According to an embodiment not according to the invention, the at least one recess for receiving the at least one electrically conductive connecting element is formed below a surface of the upper side of the heat sink as a circumferentially closed channel within the heat sink. The channel has the shape of a through-hole.

[0028] The at least one recess for receiving the at least one electrically conductive connecting element is preferably designed to extend linearly in a longitudinal direction. The cross-section of the recess is advantageously constant over its entire length.

[0029] According to a further development of the invention, the side surfaces of the device are arranged parallel to one another. The at least one recess for receiving the at least one electrically conductive connecting element is preferably oriented perpendicular to the side surfaces.

[0030] The recess is preferably designed such that the length of the at least one electrically conductive connecting element is as minimal as possible. Thus, the longitudinal extent of the recess for receiving the connecting element for connecting the electrical terminals is also minimal and can deviate from a perpendicular orientation to the side surfaces. When more than one electrically conductive connecting element and several associated recesses are formed, the recesses can be arranged in any orientation relative to one another, provided that each has a minimal longitudinal extent.

[0031] The heat sink is advantageously designed as a housing of the device, in particular as a housing of an inverter, or as a heat sink.

[0032] A further preferred embodiment of the invention consists in that the at least one electrically conductive connecting element is electrically insulated and arranged in thermal contact with the heat sink, wherein the connecting element and the heat sink are connected to one another in a thermally conductive manner.

[0033] According to the invention, the at least one electrical connection of the device, in particular of the power module for tapping an alternating voltage, is formed on the first side surface of the device, preferably on the top side of the power module.

[0034] According to the concept, the at least one electrical connection of the component to be supplied with electrical voltage is formed in a region of a side surface of the device that deviates from the first side surface, in particular in a region of the second side surface of the device.

[0035] The arrangement in the region of the side surface is to be understood as meaning that the respective electrical connection is formed on the side surface or preferably at a distance from the side surface, wherein the distance to the respective side surface is small and smaller than to one of the other side surfaces.

[0036] According to a further development of the invention, the device has a printed circuit board which is arranged above the upper side of the power module, at least partially covering the upper side.

[0037] The circuit board is preferably arranged fixed to the device via at least one signal pin, which also represents a holding element, at a distance from the top side of the power module and in particular also at a distance from the at least one electrical connection of the device.

[0038] The advantageous embodiment of the invention, especially with regard to the space-saving and simple construction, enables the use of the device in conjunction with an electrically driven compressor of a refrigerant circuit, in particular an air conditioning system for conditioning the air of a passenger compartment of a motor vehicle.

[0039] The system according to the invention for connecting electrical connections has, in summary, various advantages compared to systems known from the prior art: - structurally simple busbars with low geometric complexity and minimal lengths connect the terminals of a consumer with the terminals of the power module, whereby the busbars are significantly shorter than in conventional systems, - the busbars can also have a smaller flow cross-section, which consequently also leads to material savings, - Reducing the radiated electromagnetic interference and minimally influencing the electromagnetic compatibility behavior of the device and - minimal manufacturing and assembly costs, minimal weight and minimal installation space.

[0040] Further details, features, and advantages of embodiments of the invention will become apparent from the following description of exemplary embodiments with reference to the accompanying drawings. These show a system for connecting electrical terminals of a power supply device and electrical terminals of a consumer. Fig. 1a: from the state of the art in a plan view and Fig. 1b: in a side view and Fig. 2a: according to an embodiment of the invention in a plan view and Fig. 2b: in a side view.

[0041] The Fig. 2a and Fig. 2b each show a system 1 for connecting the electrical terminals 3 of the power supply device 2 and the electrical terminals 4 of a consumer (not shown), such as the electric motor. Fig. 2a is the system 1 in a top view and in Fig. Figure 2b shows system 1 in a side view.

[0042] The power module 5, in turn, is arranged on the underside 5b with the heat sink 6, such as the top side 6a of an inverter housing or a heat sink, thermally and mechanically coupled. Thermal coupling refers to a heat-conducting connection between the elements.

[0043] The terminals 3 of the device 2 for tapping the AC voltage, i.e., the high-current terminals of the power module 5, are designed to connect the power module 5 to the load to be supplied with voltage on the top side 5a and on a common side surface 2a of the power module 5. The top side 5a and the bottom side 5b are arranged as sides facing distal to and away from each other.

[0044] The top side 5a of the power module 5 or the device 2, which is formed with the connections 3, is arranged below the printed circuit board 7 such that the printed circuit board 7 essentially covers the entire top side 5a of the power module 5. The printed circuit board 7 is fixed to the device 2 via the signal pins 8, spaced from the top side 5a of the power module 5. The signal pins 8 serve as connection pins of the power module 5, for example, for transmitting control signals.

[0045] Since the terminals 4 of the consumer to be supplied with voltage are formed in regions of different side surfaces 2a, 2b of the device 2, at least the terminals 3, 4 of one or more pairs of terminals 3, 4 are formed at greater distances and cannot be reached in a straight line relative to one another.

[0046] The electrical connections of the electrical connections 3, 4 via the busbars designed as electrical connecting elements 9, 10 have the shortest possible connection path or the shortest possible length, despite the arrangement of the connections 3 on a common side surface 2a of the device 2 and the arrangement of the connections 4 of the component to be supplied with voltage on different side surfaces 2a, 2b of the device 2. In comparison to the prior art, the busbars 9 are not arranged directly around the device 2, in particular the heat sink 6. The busbars 9 connecting the connections 3 arranged on the first side surface 2a of the device 2 with the connections 4 of the consumer arranged in the region of the second side surface 2b of the device 2 are designed to traverse or penetrate the device 2 via the shortest possible path.

[0047] The terminal 3 of the device 2, which protrudes from the circuit board 7 or projects beyond the circuit board 7, is, like the busbar 9 arranged adjacent to the terminal 3, soldered to a conductor track 11 formed on the circuit board 7 and thus electrically connected. The conductor track 11 extends from the terminal 3 of the device 2 to the busbar 9. According to an alternative embodiment, the circuit board 7, which is arranged at a distance from the top side 5a of the power module 5, is also arranged at a distance from the terminals 3 of the device 2, at least partially covering the terminals 3.

[0048] The heat sink 6 for the power module 5 has recesses 12 in the form of grooves or channels in the region of the support surface of the power module 5, which is designed as a connecting surface or as a contact surface between the power module 5 and the heat sink 6. The recesses 12 for arranging busbars 9 as electrical connection elements are advantageously arranged in the surface of the top side 6a of the heat sink 6, which is designed, for example, as the housing of the inverter or as a heat sink.

[0049] The recesses 12, which are preferably linear in a longitudinal direction, extend from the first side surface 2a to the oppositely arranged second side surface 2b of the device 2. The channel-shaped recesses 12 are parallel to one another and perpendicular to the side surfaces 2a, 2b, which are also aligned parallel to one another. The recesses 12 have a rectangular, in particular square, cross-section, which is incorporated as a groove into the surface of the heat sink 6. The cross-sections of the recesses 12 are constant over the entire length. However, it is also possible for the cross-sections to vary in shape and size.

[0050] According to an alternative embodiment not shown, the recesses are designed as channels closed over the circumference of the cross section, which extend as through holes through the heat sink 6.

[0051] The busbars 9 electrically connecting the terminals 3, 4 are arranged at least partially within the recesses 12 and each extend from a terminal 3 of the device 2 arranged on the first side surface 2a to the recesses 12, through the recesses 12 to the second side surface 2b of the device 2 and to the terminal 4 of the consumer. Alternatively, depending on the arrangement of the terminals 4 of the consumer, the recesses can also be designed such that the busbars extend from a terminal 3 of the device 2 arranged on the first side surface 2a to the recesses 12, through the recesses 12 to the third side surface 2c or to the fourth side surface 2d of the device 2.

[0052] The busbars 9 protrude from the end faces of the recesses 12 for connection to the terminals 3, 4. The busbars 9 are coated with an electrically insulating material, particularly in the area of the recesses 12.

[0053] According to an alternative embodiment not shown, several busbars 9 are arranged within a recess.

[0054] The busbars 9 can be thermally connected to the heat sink 6 via an electrically insulating thermal paste to dissipate the heat generated in the busbars 9 and cool the busbars 9. This allows either the electrical conductor cross-section of the busbars 9 to be reduced, further minimizing material usage, while maintaining the same electrical power to be transmitted, or a less conductive material could be used while maintaining the same geometry of the busbars 9. For example, using aluminum instead of copper could further reduce costs and weight.

[0055] The system 1 for electrically connecting the electrical terminals 3, 4 is used, for example, to supply electric refrigerant compressors of air conditioning systems in motor vehicles, in which the compressor is driven by an electric motor. The electric motor of the compressor arranged in a refrigerant circuit is supplied with electrical voltage from the DC voltage network of the motor vehicle in conjunction with the voltage supply device 2 with the inverter as a converter and the power module 5.

[0056] System 1 is used, for example, for devices 2 with high-current inverters and voltages up to 60 V and currents greater than 100 A, whereby system 1 can also be used for devices 2 with high-current inverters and voltages greater than 60 V and currents lower than 100 A. List of reference symbols 1.1' system 2 Power supply device 2a first side surface device 2 2b second side surface device 2 2c third side surface device 2 2d fourth side surface device 2 3 electrical connection device 2 4 electrical connection consumer 5 Power module 5a Top side of power module 5 5b Bottom of power module 5 6 heat sink 6a Top side heat sink 7 Circuit board 8 Signal pin 9, 9' electrical connecting element, busbar 10 electrical connecting element, busbar 11 Conductor track 12 Recess

Claims

[1] System (1) for connecting electrical connections, comprising - a device (2) for supplying voltage to a power module (5) with at least one electrical connection (3), the power module (5) having a top side (5a) and a bottom side (5b), - a heat sink (6) and - at least one electrical connection (4) of a component to be supplied with an electrical voltage, where - the at least one electrical connection (3) of the device (2) is formed on a first side surface (2a) of the device (2) and the at least one electrical connection (4) of the component to be supplied with electrical voltage is formed in a region of a side surface (2b, 2c, 2d) of the device (2) that deviates from the first side surface (2a), - the connections (3, 4) are each connected to one another via an electrically conductive connecting element (9, 10) and - the underside (5b) of the power module (5) is arranged adjacent to an upper side (6a) of the heat sink (6), wherein in the region of the support of the underside (5b) of the power module (5) and the upper side (6a) of the heat sink (6), at least one recess (12) is formed, which is formed in a surface of the upper side (6a) of the heat sink (6) as a groove open on one side and extends from the first side surface (2a) to a side surface (2b, 2c, 2d) of the device (2) different from the first side surface (2a) through the device (2), wherein the open side of the recess (12) formed as a groove is closed off by the underside (5b) of the power module (5) and at least one electrically conductive connecting element (9) is arranged within the at least one recess (12). [2] System (1) according to claim 1, characterized bythat the at least one electrically conductive connecting element (9, 10) is designed as a busbar. [3] System (1) according to claim 1 or 2, characterized by that the side surfaces (2a, 2b) of the device (2) are arranged parallel to one another, and that the at least one recess (12) is formed perpendicular to the side surfaces (2a, 2b). [4] System (1) according to one of claims 1 to 3, characterized by that the heat sink (6) is designed as a housing of the device (2) or as a heat sink. [5] System (1) according to one of claims 1 to 4, characterized by that the at least one electrically conductive connecting element (9) is electrically insulated and arranged in thermal contact with the heat sink (6). [6] System (1) according to one of claims 1 to 5, characterized bythat the at least one electrical connection (4) of the component to be supplied with electrical voltage is formed in a region of the second side surface (2b) of the device (2). [7] System (1) according to one of claims 1 to 6, characterized by that the device (2) has a printed circuit board (7) which is arranged above the upper side (5a) of the power module (5), at least partially covering the upper side (5a). [8] System (1) according to claim 7, characterized by that the printed circuit board (7) is fixed to the device (2) via at least one signal pin (8) at a distance from the upper side (5a) of the power module (5).

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