Busbar-arrangement and electronic power module having such a busbar-arrangement

Abstract

The present invention relates to a busbar-arrangement (305) for an electronic power module (202), having three half-bridges (205), each having a first semiconductor package (215) and a second semiconductor package (220) electrically connected thereto, wherein the busbar arrangement (305) comprises: three first busbars (600, 605, 610) arranged spaced apart alongside each other, substantially in a first plane, a second busbar (615) arranged substantially in a second plane parallel to the first plane, a first insulating film (900) arranged between the first busbars (600, 605, 610) and the second busbar (615), three second insulating films (905), of which a second insulating film (910) covers an associated first busbar (600, 605, 610) in each case on a side facing away from the first insulating film (900), and a third insulating film (910), which covers the second busbar (615) in regions on a side facing away from the first insulating film (900). The invention also relates to an electronic power module (202) for a motor controller (200), to an electric drive axle (100) and to a motor vehicle (105).

Description

[0001] Busbar arrangement and electronic power module with such

[0002] Busbar arrangement

[0003] The present invention relates to a busbar arrangement for an electronic power module and to an electronic power module for a motor vehicle having such a busbar arrangement. The power module has at least three half-bridges, each consisting of a first semiconductor package and a second semiconductor package electrically connected thereto. A tap for connection to a load is located between the semiconductor packages. The power module is provided in an engine control system of the motor vehicle and for controlling an electric machine. The invention further relates to an electric drive axle comprising such a power module and to a motor vehicle.

[0004] For example, DE 10 2009 044 659 A1 discloses a power semiconductor module comprising a lead frame, a power semiconductor element, and a cylindrical conductor. A portion of the lead frame, the power semiconductor element, and the cylindrical conductor are each sealed with a compression-molding resin, with terminal portions of the lead frame protruding from peripheral side portions of the power semiconductor module, and an opening of the cylindrical conductor being exposed on an upper surface of the power semiconductor module.

[0005] One object of the invention is to provide a compact busbar arrangement for an electronic power module that enables low stray inductance. The invention achieves this object by means of the subject matter of the independent claims. Subclaims specify preferred embodiments.

[0006] A busbar arrangement according to the invention for an electronic power module, which has three half-bridges, each with a first semiconductor package and a second semiconductor package electrically connected thereto, comprises: three first busbars, which are arranged next to one another at a distance from one another essentially in a first plane, a second busbar, which is arranged essentially in a second plane arranged parallel to the first plane, a first insulation film, which is arranged between the first busbars and the second busbar, three second insulation films, of which a second insulation film each covers an associated first busbar in regions on a side facing away from the first insulation film, and a third insulation film, which covers the second busbar in regions on a side facing away from the first insulation film.

[0007] The semiconductor packages are to be understood as discrete individual packages of an electronic power module. Two semiconductor packages each form the half-bridge for the power module of a motor controller. Several half-bridges can be provided for separate control to operate an electric motor of an electric drive axle. The semiconductor package is used to switch current, particularly for consumers in the several tens of kW range, especially for electrical machines, e.g., for a motor vehicle.

[0008] A semiconductor package preferably has at least two load terminals with different potentials. Two or more first load terminals with a first potential can be provided. Likewise, two or more second load terminals with a different second potential can be provided. A ceramic substrate is preferably arranged between the load terminals with different potentials, on which a plurality of power semiconductors and a control terminal are electrically arranged.

[0009] The semiconductor package can therefore comprise a ceramic substrate having a ceramic layer between a lower copper layer and an upper copper layer, two first load terminals, each with a leadframe, wherein one of the first load terminals is assigned to at least one first power semiconductor and the other first load terminal is assigned to at least one second power semiconductor, and wherein the respective power semiconductor is arranged between the upper copper layer of the ceramic substrate and the leadframe of the associated first load terminal and is electrically connected thereto, a second load terminal that is electrically connected to the upper copper layer, and a control terminal that is electrically connected to signal pins for controlling the semiconductor package and to the power semiconductors via connecting elements. The first load terminals and the second load terminal have different potentials.

[0010] By providing multiple load terminals with the same potential, current symmetry within the semiconductor package can be improved. By assigning at least one power semiconductor or chip to each first load terminal, the number of power semiconductors on a given area of ​​the ceramic substrate can be increased. In other words, the packing density of the semiconductor package is maximized. By appropriately arranging the first load terminals, the second load terminal, and the power semiconductors, i.e., by selecting a suitable topology for the semiconductor package, current symmetry can also be achieved. The semiconductor package is current-symmetrical if the current flow within the semiconductor package is evenly distributed. This means that the current in different paths or branches of a circuit is always the same.Current symmetry ensures that the circuit functions properly and no undesirable effects occur.

[0011] The lower copper layer of the ceramic substrate is designed to be connected to a heat sink of the power module. In other words, the lower copper layer is designed for cooling. The lower copper layer is understood as the back or underside of the package, which is, for example, firmly bonded to a heat sink.

[0012] The first load terminal(s) of the respective semiconductor package form(s) the AC terminal or the "source" side of the semiconductor package. By providing preferably two first load terminals, the power supply can be split and routed specifically into the semiconductor package. This allows the semiconductor package to be made more compact and, due to the identical number of corresponding power semiconductors per first load terminal, current symmetry can be achieved. This makes it possible to increase the power density while maintaining a compact design. The second load terminal(s) form(s) the DC plus terminal or the "drain" side of the semiconductor package. Optionally, the semiconductor package also comprises third load terminals that have the same potential as the second load terminal.

[0013] The control terminal is connected to signal transmission means, for example, in the form of signal pins. The signal pins are provided for gate control of the semiconductor package. The power semiconductors of the respective semiconductor package are controlled, at least indirectly, via the signal pins. The signal pins are connected to the power semiconductors for signal transmission. The control terminal can be electrically connected to the power semiconductors via bond wires.

[0014] The respective semiconductor package can be encapsulated using injection molding to insulate the components of the semiconductor package. In other words, the semiconductor package is encapsulated using a so-called molding process. The molding process is a method in which a plastic housing consisting of insulating material is formed around one or more power semiconductors. The encapsulation protects the power semiconductors from external influences such as moisture and dust. The molding process involves injecting liquid plastic as insulating material into a mold in which the components of the semiconductor package are placed. After the plastic has hardened, the mold or tool is removed, protecting the semiconductor package. The semiconductor package is encapsulated, for example, using transfer or compression molding.

[0015] In transfer molding, a defined amount of a molding material, typically a thermoset or thermoplastic, is poured into a mold cavity through a sprue. During transfer molding, the mold walls are typically heated to a temperature above the melting temperature of the molding material to ensure good flow properties within the cavity. A wide variety of thermoplastics and thermosets are suitable for transfer molding.

[0016] The busbar arrangement has a multi-layer construction. The busbars of the busbar arrangement are each made of an electrically conductive material, in particular metal. The busbars can be formed by punching and forming. The respective first busbar is provided for the AC connection (alternating current connection). The second busbar is provided for the DC negative connection (direct current connection negative side). The first busbars on the one hand and the second busbar on the other hand have different potentials, with the insulating film arranged between them having an insulating effect. The externally arranged insulating films serve to shield and protect the busbars from external influences and / or neighboring components. The respective insulating film facing the heat sink can electrically shield against the semiconductor packages orinsulate, whereby the insulation foil arranged on the opposite side of the busbar arrangement and facing a circuit board can shield or insulate against the circuit board.

[0017] The layer structure of the busbar arrangement can be configured in different ways. In a first embodiment of the busbar arrangement, with respect to a space between the semiconductor packages or the half-bridges on the one hand and a printed circuit board on the other hand, the first level in which the first busbars are arranged can be arranged above the second level in which the second busbar is arranged, i.e., on a side of the second busbar facing away from the half-bridges.

[0018] The printed circuit board (PCB) is preferably a printed circuit board (PCB). A PCB (printed circuit board) is an electrical circuit consisting of an insulating material on which conductive connections or tracks are applied. A printed circuit board (PCB) is used to mechanically attach and electrically connect electronic components. Components such as sensors, resistors, capacitors, transistors, and / or integrated circuits can be mounted on a printed circuit board to create an electronic circuit. Conductive tracks on the board enable electrical flow between the components and establish connections to other printed circuit boards or components.

[0019] Alternatively, the order of the levels may be reversed when assembled.

[0020] Accordingly, the second level with the second busbar can be arranged above the first level with the first busbars, i.e., on a side of the first busbars facing away from the half-bridges. The second busbar (DC negative) can be used as an EMC shield between the first busbars (AC, i.e., switched potential) and the circuit board. An EMC shield, also known as an electromagnetic compatibility shield, is a device or structure designed to shield or at least reduce electromagnetic fields. The purpose of an EMC shield is to protect sensitive electronic devices or systems, such as circuit boards or semiconductor packages, from unwanted, external electromagnetic interference.

[0021] The insulation films are preferably made of plastic and can have an adhesive layer in order to attach the respective insulation film to at least one of the mentioned busbars or to connect it integrally to it. The respective insulation film preferably has a maximum thickness of 400 μm. The thinner the insulation film, the smaller the distance between the busbars of the different levels and the lower the stray inductance. The insulation films ensure a minimal distance between the busbars in the power module. The busbars can be arranged directly on top of one another and only spatially separated by a thin insulation layer or insulation film. This creates a low-inductance busbar design for the busbar arrangement that is space-saving and safe.The busbar arrangement enables a minimal power loop and maximum overlap, which has a positive effect on stray inductance. This type of busbar arrangement can be used regardless of the power module layout, for an AM B (Active Metal Brazing) substrate, a DBC (Direct Copper Bonding) substrate, or an embedded PCB assembly. Depending on the design, the insulation foils can be placed against one another, forming a shell-like structure to protect and shield the busbars.

[0022] Preferably, a first busbar of the busbar arrangement has at least four load connection points. Preferably, all first busbars each have at least four load connection points. All load connection points of the respective first busbar are connected to one another, in particular formed as a single piece. The load connection points are provided for different connections. At least one of the load connection points can be assigned to a "source" side. At least one further load connection point can be assigned to a "drain" side. At least one further load connection point can form a center tap for connecting or energizing the electric machine of the electric drive axle.

[0023] In this sense, a first load connection point of the respective first busbar is preferably provided for external connection of the busbar arrangement, a second load connection point of the respective first busbar is provided for electrical connection to a first semiconductor package of a half-bridge, in particular to a second load connection of the first semiconductor package, and two third load connection points of the respective first busbar are preferably provided for electrical connection to a second semiconductor package of the same half-bridge, in particular to a first load connection of the second semiconductor package.

[0024] In one embodiment, the two third load connection points of the respective first busbar are arranged on opposite sides of the respective first busbar. The third load connection points are preferably mirror-inverted. This allows current symmetry within the respective semiconductor package, provided the semiconductor package is also substantially mirror-symmetrical. In this context, reference is made to the above explanations regarding the design of the respective semiconductor package. The arrangement of the load connection points of the respective first busbar is adapted to the arrangement of the load connections of the associated semiconductor package and the external connection.

[0025] In a further development of the invention, two fourth load connection points of the respective first busbar are configured for electrical connection to a first semiconductor package of the same half-bridge. The fourth load connection points are designed as additional first connection tabs, which are configured to be connected to load connections of a respective first semiconductor package of the associated half-bridge, provided that the associated first semiconductor package, for example to implement or improve current symmetry within the semiconductor package, has two further, in particular third, load connections, which are assigned to the "drain" side analogously to the second load connection of the semiconductor package. Accordingly, a fourth load connection point is assigned to a further, third load connection of the semiconductor package.The fourth load connection points are additional connections, each for an AC connection on the first semiconductor package assigned to the respective first power rail, thus achieving better current distribution within the first semiconductor package of the respective half-bridge. This reduces stray inductance.

[0026] The second busbar preferably has a plurality of load connection points. All load connection points of the second busbar are connected to one another, in particular formed as a single piece. In one embodiment, four first load connection points of the second busbar are configured for externally connecting the busbar arrangement, in particular to an intermediate circuit capacitor; two second load connection points of the second busbar are configured for electrically connecting to a first semiconductor package of a first half-bridge; two third load connection points of the second busbar are configured for electrically connecting to a first semiconductor package of a second half-bridge; and two fourth load connection points of the second busbar are configured for electrically connecting to a first semiconductor package of a third half-bridge. The number of first load connection points can be adapted depending on the design of the power module.

[0027] In one embodiment, the second busbar has three parallel tabs, wherein the second, third, and fourth load connection points of the second busbar are each assigned to a tab and formed on opposite sides of the respective tab in order to electrically connect the second busbar to a respective load terminal of a first semiconductor package of the respective half-bridge. The second, third, or fourth load connection points are each arranged parallel to one another and configured to be connected to three adjacent and spaced-apart first semiconductor packages, a second, third, or fourth load connection point to an associated first load terminal of the associated first semiconductor package. This likewise improves the current symmetry within the respective semiconductor package and reduces stray inductance.The arrangement of the load connection points of the second busbar is adapted to the arrangement of the load connections of the associated semiconductor package and the external connection.

[0028] In a further development of the invention, the busbar arrangement further comprises three third busbars which are arranged next to one another at a distance from one another in a third plane. The respective third busbar is provided for the DC plus connection (direct current connection plus side). The third busbars are provided when the associated second semiconductor package has two further, in particular third, load connections, for example to implement or improve current symmetry within the semiconductor package, which are assigned to the "drain" side in a similar way to the second load connection of the semiconductor package. A third busbar can rest on a second semiconductor package of the respective half-bridge and connects the load connections of the respective second semiconductor package assigned to the "drain" side to one another, provided that more than one such load connection is provided.

[0029] Accordingly, each third busbar has at least two load connection points, which are assigned to a further, third load connection of the semiconductor package. This achieves better current distribution within the second semiconductor package of the respective half-bridge. Furthermore, a reduction in stray inductance is achieved. The respective third busbar is therefore designed to connect several load connections of the associated second semiconductor package with the same potential to one another before an external connection, in particular the DC plus connection, is made. The respective third busbar has at least two, and for current symmetry reasons preferably three, load connection points. The respective third busbar is an additional DC plus busbar with a DC plus connection for better current distribution in the associated second semiconductor package.If the respective second semiconductor package has only one load connection on the "drain" side, a third busbar can be omitted. The third busbar is preferably arranged spatially between the respective second semiconductor package and the layer structure consisting of the first busbars and the second busbar. Depending on the arrangement of the first busbars and the second busbar relative to one another, the third busbars can thus, in a first example, be arranged spatially between the respective second semiconductor package and the first level with the first busbars, wherein a second insulation film is arranged between the respective third busbar and the associated first busbar.

[0030] In a second example, the third busbars can be spatially arranged between the respective second semiconductor package and the second level with the second busbar, wherein the third insulation film is arranged between the respective third busbar and the second busbar.

[0031] In a further development of the invention, at least one temperature sensor is arranged on at least one of the insulation films. Thus, at least one temperature sensor can be integrated into the busbar arrangement. Preferably, several temperature sensors are provided to determine the temperature of the busbar arrangement and / or other components of the power module. The temperature sensor(s) are provided, in particular, for monitoring the semiconductor packages. Contacting the respective temperature sensor to the circuit board can be achieved via additional pins or a flexible film.

[0032] In a further development of the invention, a current sensor is arranged on at least one of the three first busbars. The respective current sensor is provided for measuring an alternating current (AC current) on the first busbar on which the current sensor is arranged. Contacting of the at least one current sensor to the circuit board can be achieved via additional pins or flexible foil. Preferably, an associated current sensor is arranged on each first busbar in order to tap the alternating current applied to each first busbar. The respective current sensor is preferably arranged on a side of the respective first busbar opposite the semiconductor packages, in particular on a top side of the busbar arrangement or a side of the busbar arrangement facing the circuit board.

[0033] In a further aspect of the invention, an electronic power module according to the invention for a motor controller comprises a heat sink, three half-bridges, each with two semiconductor packages, i.e., a total of six semiconductor packages, and a busbar arrangement described herein, which electrically connects the half-bridges to one another. The respective semiconductor package can be connected to the heat sink, for example, using so-called nanowire technology, by sintering, soldering, or pressing using an organic insulator. The semiconductor package can be connected directly to the heat sink via a lower copper layer. Alternatively, an insulation layer can be arranged between the semiconductor package, in particular its lower copper layer, and the heat sink.

[0034] The power module preferably comprises a first connection element for the external connection of a second semiconductor package of the half-bridges. The first connection element can be a stamped sheet metal part that connects the second semiconductor packages of the half-bridges to one another and to an external connection point, in particular a DC link capacitor. The first connection element connects the load connection assigned to the "drain" side of the respective second semiconductor package to one another and the load connection(s) assigned to the "drain" side of the further second semiconductor packages of other half-bridges to one another and functions as a connecting or coupling element for connection to an external connection point. If the busbar arrangement comprises third busbars, the first connection element is connected to the third busbars.The respective third busbar is therefore arranged between the load terminal(s) assigned to the "drain" side of the respective second semiconductor package and the first connection element. The first connection element is preferably understood as a DC plus connection.

[0035] The power module preferably also includes a second connection element for externally connecting the four first load connection points of the second busbar. The second connection element can be a stamped sheet metal part that connects the second busbar to an external connection point. The second connection element brings together the first load connection points of the second busbar and is connected externally. The second connection element is preferably to be understood as a DC negative connection. The second connection element can, for example, be connected to an intermediate circuit capacitor.

[0036] The power module can be designed such that, for example, twelve semiconductor packages are arranged on the heat sink, with two semiconductor packages each combined to form a half-bridge and each connected in series. The resulting three or six half-bridges are preferably electrically connected in parallel. For three half-bridges with a total of six semiconductor packages, one semiconductor package is provided per switching position. For six half-bridges with a total of twelve semiconductor packages, two semiconductor packages are provided per switching position. Regardless of the number of semiconductor packages, all semiconductor packages can be arranged and cooled together on the heat sink, for example in the form of a cooling plate or the like.

[0037] In a further aspect of the invention, an electric drive axle according to the invention, also called an E-axle, comprises an electric machine and an electronic power module proposed herein. The electric machine is a three-phase electric machine. The power module is provided in a motor controller that controls the electric machine. Thus, the motor controller is designed in particular to control a three-phase electric machine. In addition to the electric machine, the electric drive axle can comprise an optional transmission to provide a torque and a speed for driving a drive wheel of the motor vehicle. In addition to the electric machine, a motor controller can also be included. The electric machine is supplied with electrical energy from an energy storage device.

[0038] In a further aspect of the invention, a motor vehicle according to the invention comprises an electric drive axle according to the invention or an electronic power module according to the invention. The motor vehicle can, in particular, comprise a motorcycle, a passenger car, a truck, or a bus. The motor vehicle comprises at least two axles. Preferably, two axles are provided, with at least one of the axles being an electric drive axle and being drivable by at least one electric machine.

[0039] The above definitions and statements regarding technical effects, advantages, and advantageous embodiments of the semiconductor package according to the invention also apply mutatis mutandis to the power module according to the invention according to the second aspect of the invention, to the electric drive axle according to the invention according to the third aspect of the invention, and to the motor vehicle according to the invention according to the fourth aspect of the invention, and vice versa. It is understood that the features mentioned above and those to be explained below can be used not only in the respective combinations specified, but also in other combinations or on their own, without departing from the scope of the present invention.

[0040] To the extent that elements are designated by numbering, for example, "first component," "second component," and "third component," this numbering is intended purely for differentiation in the designation and does not represent any interdependence of the elements or a mandatory sequence of the elements. This means, in particular, that a device does not have to have a "first component" in order to have a "second component." The device may also comprise a "first component" and a "third component," but without necessarily having a "second component."

[0041] The invention will now be described in more detail with reference to the accompanying figures, in which:

[0042] Figure 1 is a highly schematic view of a motor vehicle with an electric drive axle;

[0043] Figure 2 shows an exemplary motor control of the drive axle, comprising an electronic power module according to the invention with half-bridges according to a first embodiment; Figure 3 shows a schematic perspective view of the power module according to the invention according to Figure 2 in the assembled state with a busbar arrangement according to the invention;

[0044] Figure 4 is a schematic perspective view of a semiconductor package of the power module according to the invention shown in Figure 3;

[0045] Figure 5 is a schematic exploded view of the power module according to the invention shown in Figure 3;

[0046] Figure 6 is a schematic perspective view of the busbar arrangement according to the invention shown in Figures 3 and 5;

[0047] Figure 7 is a schematic perspective view of first busbars of the busbar arrangement according to the invention according to Figures 3 to 6;

[0048] Figure 8 is a schematic perspective view of a second busbar of the busbar arrangement according to the invention according to Figures 3 to 7;

[0049] Figure 9 is a schematic perspective view of insulation films of the busbar arrangement according to the invention according to Figures 3 to 8;

[0050] Figure 10 is a detailed sectional view of the busbar arrangement according to Figures 3 to 9 to illustrate the layer structure;

[0051] Figure 11 is a schematic perspective view of the power module according to the invention according to a second embodiment;

[0052] Figure 12 is a detailed perspective view of the power module according to the invention shown in Figure 11;

[0053] Figure 13 is a schematic perspective view of the power module according to the invention according to a third embodiment without showing part of the busbar arrangement;

[0054] Figure 14 is a schematic perspective view of the power module according to the invention according to a third embodiment; and

[0055] Figure 15 shows a schematic perspective view of the power module according to the invention according to a fourth embodiment; wherein identical or similar components are provided with the same reference numerals. Figure 1 shows an electric drive axle 100 in a motor vehicle 105. The motor vehicle 105 can additionally include an internal combustion engine 110, which is connected to a drive wheel 120 of the motor vehicle 105 via a transmission 115. In this case, the motor vehicle 105 would be a hybrid vehicle.

[0056] The electric drive axle 110 comprises an electric machine 125, which can also act on the drive wheel 120, preferably by means of the transmission 115. Furthermore, a power converter 130 can be provided, which can be fed with electrical energy from an electrical energy storage device 135. The electrical energy storage device 135 is preferably electrochemically constructed, but a fuel cell or another power source can also be used, for example. The power converter 130 is preferably configured to provide phase-shifted alternating currents to the electric machine 125. The machine 125 is implemented, for example, as a permanent-magnet synchronous machine, but other embodiments are also possible. The voltages and frequencies of the alternating currents provided can be determined such that the electric machine 125 converts a predetermined torque or rotates at a predetermined speed.A field-oriented control system can be implemented to control the direction of rotation and speed. The nominal voltage of the electrical energy storage device 135 is typically several hundred to over 1000 V. The current through the electrical machine 125 can be several hundred A.

[0057] Figure 2 shows a motor controller 200 with a power module 202, comprising three half-bridges 205, which can be controlled, for example, by means of a common control device 210. The motor controller 200 is configured to control the rotational behavior of the electric machine 125 and typically operates digitally using a microcomputer.

[0058] Each half-bridge 205 comprises two semiconductor packages 215, 220, divided into an upper semiconductor package 215 and a lower semiconductor package 220, wherein the semiconductor packages 215, 220 are connected in series between DC voltage potentials of the energy storage device 135 as shown. A DC link capacitor 225 is preferably provided between the potentials. A center tap 230 between the semiconductor packages 215, 220 is connected to an associated phase of the electric machine 125. The upper semiconductor package 215 lies between a high potential of the energy storage device 135 and the center tap 230, and the lower semiconductor package 220 lies between the center tap 230 and a low potential of the energy storage device 135.

[0059] The semiconductor packages 215, 220 can be controlled independently of one another, each like an electrical switch, to close or open. The control device 210 is configured to alternately close and open the semiconductor packages 215, 220, so that at no time are both semiconductor packages 215, 220 of a half-bridge 205 closed. A voltage that occurs at the center tap 230 of the respective half-bridge 205 depends on a ratio of the duty cycles of the upper semiconductor package 215 and the lower semiconductor package 220. During normal operation of the electric machine 125, predetermined currents can thus be controlled through the semiconductor packages 215, 220.

[0060] Figure 3, in conjunction with Figure 5, discloses an electronic power module 202 for the engine control 200, comprising a heat sink 300 on which three half-bridges 205, each with two semiconductor packages 215, 220, are arranged in a 2x3 arrangement, i.e. three first semiconductor packages 215 in the lower row here and three second semiconductor packages 220 electrically connected thereto. The electrical connection of the semiconductor packages 215, 220 of the respective half-bridge 205 and the connection to external connection points is effected via a busbar arrangement 305 according to the invention, which is described in more detail below using several exemplary embodiments. Such a power module 202 is also shown in Figures 11, 14 and 15. The power module 202 can alternatively also be provided with twelve semiconductor packages 215, 220 orSix half-bridges 205 can be arranged jointly on the heat sink 300, with two semiconductor packages 215, 220 each being assigned as discrete individual packages to a switching position of the power module 202. The semiconductor packages 215, 220 of the power module 202 are identically designed regardless of their number, so that this applies equally to the semiconductor package 215, 220 shown here and analogously to the other five semiconductor packages 215, 220 of the power module 202, regardless of whether it is the first semiconductor package 215 or the second semiconductor package 220 of the respective half-bridge 205.

[0061] According to Figure 5, on the surface of the heat sink 300 there is a compensation layer 500 for receiving the respective semiconductor package 215, 220. The compensation layer 500 further improves the contact between the respective semiconductor package 215, 220 and the heat sink 300. The compensation layer 500 can be, for example, a sintered or soldered layer, an organic insulator or nanowire.

[0062] Figure 4 shows an exemplary semiconductor package 215, 220 in the manufactured state as a separately handleable unit. The semiconductor package 215, 220 is assigned as a discrete individual package to a switching position of the power module 202. Figure 4 shows five load terminals 405-425 and four signal pins 430-445, some of which can be provided for gate control and some for signal-transmitting connections to other components, for example, a temperature sensor for monitoring the temperature of the respective semiconductor package 215, 220. With regard to the signal pins 430-445, reference is made, for example, to Figure 3, where the busbar arrangement 305 has a plurality of openings 320, each of which is provided for the passage of two of the signal pins 430-445 to a printed circuit board (not shown).

[0063] The semiconductor package 215, 220 is encapsulated by injection molding, wherein an insulating material 400 forms a housing of the semiconductor package 215, 220, so to speak, in order to protect the components of the semiconductor package 215, 220, where necessary, from interaction with one another and from external influences, in particular dirt and moisture.

[0064] In the present case, the semiconductor package 215, 220 has two first load terminals 405, 410 with the same first potential, a second load terminal 415 with a second potential different from the first potential, and two third load terminals 420, 425, likewise with the second potential. Here, one of the third load terminals 420, together with one of the first load terminals 405, is assigned to one of the longer sides of the semiconductor package 215, 220, which is rectangular in plan view, wherein the other third load terminal 425, together with the other first load terminal 410, is assigned to the opposite side of the semiconductor package 215, 220. The second load terminal 415 is assigned to the shorter side of the semiconductor package 215, 220 that is further away from the third load terminals 420, 425 in order to realize current symmetry within the semiconductor package 215, 220.The two third load terminals 420, 425 have the same potential as the second load terminal 415.

[0065] A ceramic substrate (not shown here) is arranged between the load terminals 405-425 of different potentials. Several power semiconductors (not shown here) and a control terminal (also not shown here) are electrically mounted on the substrate. The power semiconductors are controlled via the control terminal and are supplied with electrical energy via the load terminals 405-425. The signals for the control terminal are transmitted via the signal pins 430-445.

[0066] The load terminals 405-425 each have a surface that lies in a plane with a surface of the insulation material 400, thereby forming the flat upper surface of the semiconductor package 215, 220 shown in Figure 4. Via the load terminals 405-425, the semiconductor packages 215, 220 of a half-bridge 205 are connected to each other, to the busbar arrangement 305, and externally.

[0067] Figure 6 in conjunction with Figures 7 to 10 shows the busbar arrangement 305 according to the invention in detail. The busbar arrangement 305 comprises three first busbars 600, 605, 610, which are arranged spaced apart from one another essentially in a first plane. The first plane is illustrated in Figure 7. The first busbars 600, 605, 610 carry an alternating current (HV AO). The busbar arrangement 305 further comprises a second busbar 615, which is arranged essentially in a second plane arranged parallel to the first plane. The second plane is illustrated in Figure 8. The second busbar 615 forms the direct current negative side (HV DO minus).

[0068] The expression “essentially in one plane” means that the largest part of the respective busbar 600, 605, 610, 615 is flat, whereby only individual legs, arms or segments can be provided which are reshaped for better connection of the respective busbar 600, 605, 610, 615.

[0069] Figure 9, in conjunction with Figure 10, also shows several insulating foils 900, 905, 910, which together, as a type of layer system, form a protective sheath for the busbar arrangement 305. The insulating foils 900, 905, 910 can be glued to the respective busbar or busbar and, if necessary, post-treated. In the detailed sectional view according to Figure 10, a first insulating film 900 is arranged between the first busbars 600, 605, 610 and the second busbar 615, i.e., between the first and second planes. Three second insulating films 905 are provided, each of which is assigned a second insulating film 905 to a first busbar 600, 605, 610 and covers it in an insulating manner in sections, as well as a third insulating film 910, which partially covers the second busbar 615 on a side facing away from the first insulating film 900. The insulating films 900, 905, 910 have a thickness of approximately 300 to 400 μm in the present case.

[0070] As can be seen in particular from Figure 7, each first busbar 600, 605, 610 has four load connection points 700, 705, 710, 715. A first load connection point 700 of the respective first busbar 600, 605, 610 forms the aforementioned center tap 230 for externally connecting the busbar arrangement 305 to the electric machine 125. A second load connection point 705 of the respective first busbar 600, 605, 610 is provided for electrically connecting the first busbar 600, 605, 610 to the second load connection 415 of the associated first semiconductor package 215 of a half-bridge 205. Two third load connection points 710, 715 of the respective first busbar 600, 605, 610 are arranged on opposite sides of the respective first busbar 600, 605, 610 and are provided for electrically connecting the first busbar 600, 605, 610 to the associated second semiconductor package 220 of the same half-bridge 205.The second and third load connection points 705, 710, 715 are plastically deformed for connection to the first load connections 405, 410 of the second semiconductor package 220 and are therefore not located in the first plane with the rest of the respective first busbar 600, 605, 610.

[0071] Figure 8 clearly shows that the second busbar 615 has a plurality of load connection points 800, 805, 810, 815, 820, 825, 830. In the present case, four first load connection points 800 of the second busbar 615 are provided for the external connection of the busbar arrangement 305, here for the connection to the intermediate circuit capacitor 225. Two second load connection points 805, 810 of the second busbar 615 are provided for the electrical connection to a first semiconductor package 215 of the left, first half-bridge 205 according to Figure 5. Two third load connection points 815, 820 of the second busbar 615 are provided for the electrical connection to a first semiconductor package 215 of the middle, second half-bridge 205 according to Figure 5. Two fourth load connection points 825, 830 of the second busbar 615 are provided for electrical connection to a first semiconductor package 215 of a right, third half-bridge 205 according to Figure 5.The load connection points 800, 805, 810, 815, 820, 825, 830 are designed here as sheet metal sections which are provided for contacting with external connection means or with load connections 405, 410 of the respective first semiconductor package 215.

[0072] The second busbar 615 has three parallel tabs 835, 840, 845, wherein the second load connection points 805, 810 are formed on the first tab 835, the third load connection points 815, 820 are formed on the second tab 840, and the fourth load connection points 825, 830 are formed on the third tab 845. The load connection points 805-830 of the respective tabs 835-845 are formed on opposite sides of the respective tabs 835-845 in order to electrically connect the second busbar 615 to a respective first load terminal 405, 410 of the associated first semiconductor package 215 of the respective half-bridge 205. The second, third and fourth load connection points 805 - 830 are plastically deformed for connection to the first load connections 405, 410 of an associated first semiconductor package 220 and are therefore not located with the rest of the second busbar 615 in the second plane.According to Figures 11 and 12, which show a second embodiment of the power module 202, each first busbar 600, 605, 610 has two fourth load connection points 1100, 1105 for electrically connecting the respective first busbar 600, 605, 610 to the third load connections 420, 425 of the associated first semiconductor package 215. Thus, the respective first busbar 600, 605, 610 is electrically connected both via the second load connection point 705 to the second load connection 415 of the associated first semiconductor package 215 and via the fourth load connection points 1100, 1105 to the third load connections 420, 425 of the same first semiconductor package 215. For further details, reference is made to the explanations regarding the first embodiment.

[0073] In a third embodiment of the power module 202 according to Figure 13, the busbar arrangement 305 comprises three third busbars 1300, 1305, 1310, which are arranged next to one another at a distance from one another in a third plane. For a better understanding of this embodiment, the further planes of the busbar arrangement 305 are not shown in Figure 13. The third busbars 1300, 1305, 1310 each form a direct current plus side (HV DC Plus). Each third busbar 1300, 1305, 1310 is configured such that, in the assembled state, it contacts both the second load terminal 415 and the third load terminals 420, 425 of the associated second semiconductor package 220 of the respective half-bridge 205. The third level with the third busbars 1300, 1305, 1310 is spatially arranged between the second semiconductor packages 220 and the remaining busbar arrangement 305, i.e. the first and second levels.Depending on the arrangement sequence of the first and second levels, the third busbars 1300, 1305, 1310 are arranged vertically between the top side of the second semiconductor packages 220 and either the first level with the first busbars 600, 605, 610 or between the top side of the second semiconductor packages 220 and the second level with the second busbar 615. The third busbars 1300, 1305, 1310 therefore come into contact, on a side facing away from the second semiconductor packages 220, either with the respective second insulation film 905 covering the associated first busbar 600, 605, 610 or with the third insulation film 910 covering the second busbar 615. For the rest, reference is made to the explanations regarding the first embodiment.

[0074] A fourth embodiment of the power module 202 is shown in Figure 14, which shows the power module 202 in the assembled state. It is merely intended to illustrate here that at least one temperature sensor 1400 is arranged on the upper insulation film, be it the second or third insulation film 905, 910, depending on the arrangement of the first and second levels. In the present case, based on the layer structure, two temperature sensors 1400 are provided on the second insulation film 905, which here forms the uppermost layer of the busbar arrangement 305. The temperature sensors 1400 measure the temperature of the power module 202, in particular of the busbar arrangement 305. The temperature sensors 1400 can be arranged or attached to the respective insulation film 905, 910 by means already known. For further details, reference is made to the explanations regarding the third embodiment.

[0075] A fifth embodiment of the power module 202 is shown in Figure 15, which shows the power module 202 in the assembled state. It is merely intended to illustrate here that a current sensor 1500 is arranged on each of the first busbars 600, 605, 610 to sense the alternating current of the respective first busbar 600, 605, 610. For further details, please refer to the explanations regarding the third embodiment.

[0076] According to Figures 3, 5 and 11, the power module 202 further comprises a first connection element 310 for the external connection of the second semiconductor packages 220 of the half-bridges 205, here via the respective second load connection 415. If, as provided in the embodiments according to Figures 13 to 15, third busbars 1300, 1305, 1310 are arranged in a third plane, a third busbar 1300, 1305, 1310 is arranged in an electrically conductive manner between the associated second load connection 415 and the first connection element 310. The first connection element 310 forms a DC plus connection of the power module 202. According to Figures 3, 5, and 11, the power module 202 also includes a second connection element 315 for externally connecting the four first load connection points 800 of the second busbar 615. The second connection element 315 forms a DC minus connection of the power module 202.For the sake of simplicity, the connection elements 310, 315 are not shown in Figures 14 and 15.

[0077] Reference symbol electric drive axle

[0078] motor vehicle

[0079] combustion engine

[0080] Gearbox

[0081] Drive wheel electric machine

[0082] power converter

[0083] Energy storage

[0084] Engine control

[0085] Power module

[0086] Half bridge

[0087] Control device

[0088] Upper semiconductor package of the semiconductor bridge

[0089] Lower semiconductor package of the semiconductor bridge

[0090] DC link capacitor

[0091] Center tap

[0092] heat sink

[0093] Busbar arrangement

[0094] First connecting element

[0095] Second connection element

[0096] breakthrough

[0097] Insulation material of the semiconductor package

[0098] First load connection

[0099] First load connection

[0100] Second load connection

[0101] Third load connection

[0102] Third load connection

[0103] Signal pin 25 Signal pin 30 Signal pin 35 Signal pin 00 Leveling layer 00 First busbar 05 First busbar 10 First busbar 15 Second busbar 00 First load connection point of the first busbar 05 Second load connection point of the first busbar 10 Third load connection point of the first busbar 15 Third load connection point of the first busbar 00 First load connection point of the second busbar 05 Second load connection point of the second busbar 10 Second load connection point of the second busbar 15 Third load connection point of the second busbar

[0104] 820 Third load connection point of the second busbar

[0105] 825 Fourth load connection point of the second busbar

[0106] 830 Fourth load connection point of the second busbar

[0107] 835 First tab of the second busbar

[0108] 840 Second tab of the second busbar

[0109] 845 Third tab of the second busbar

[0110] 900 First insulation film

[0111] 905 Second insulation film

[0112] 910 Third insulation film

[0113] 1100 Fourth load connection point of the first busbar

[0114] 1105 Fourth load connection point of the first busbar 1300 Third busbar

[0115] 1305 Third busbar

[0116] 1310 Third busbar

[0117] 1400 temperature sensor

[0118] 1500 current sensor

Claims

Patent claims 1. Busbar arrangement (305) for an electronic power module (202), which has three half-bridges (205), each with a first semiconductor package (215) and a second semiconductor package (220) electrically connected thereto, wherein the busbar arrangement (305) comprises: three first busbars (600, 605, 610), which are arranged spaced apart from one another essentially in a first plane, a second busbar (615), which is arranged essentially in a second plane arranged parallel to the first plane, a first insulation film (900), which is arranged between the first busbars (600, 605, 610) and the second busbar (615), three second insulation films (905), of which a respective second insulation film (910) covers an associated first busbar (600, 605, 610), in each case on a side facing away from the first insulation film (900). partially covered, as well as a third insulation foil (910),which partially covers the second busbar (615) on a side facing away from the first insulation film (900).

2. Busbar arrangement (305) according to claim 1, wherein a first busbar (600, 605, 610) has at least four load connection points (700, 705, 710, 715).

3. Busbar arrangement (305) according to claim 2, wherein a first load connection point (700) of the respective first busbar (600, 605, 610) is configured for external connection of the busbar arrangement (305), a second load connection point (705) of the respective first busbar (600, 605, 610) is configured for electrical connection to a first semiconductor package (215) of a half-bridge (205), and two third load connection points (710, 715) of the respective first busbar (600, 605, 610) are configured for electrical connection to a second semiconductor package (220) of the same half-bridge (205).

4. Busbar arrangement (305) according to claim 3, wherein the two third load connection points (710, 715) of the respective first busbar (600, 605, 610) are connected to opposite sides of the respective first busbar (600, 605, 610).

5. Busbar arrangement (305) according to one of claims 2 to 4, wherein two fourth load connection points (1100, 1105) of the respective first busbar (600, 605, 610) are arranged for electrical connection to a first semiconductor package (215) of the same half-bridge (205).

6. Busbar arrangement (305) according to one of the preceding claims, wherein the second busbar (615) has a plurality of load connection points (800, 805, 810, 815, 820, 825, 830).

7. Busbar arrangement (305) according to claim 5, wherein four first load connection points (800) of the second busbar (615) are configured for external connection of the busbar arrangement (305), two second load connection points (805, 810) of the second busbar (615) are configured for electrical connection to a first semiconductor package (215) of a first half-bridge (205), two third load connection points (815, 820) of the second busbar (615) are configured for electrical connection to a first semiconductor package (215) of a second half-bridge (205), and two fourth load connection points (825, 830) of the second busbar (615) are configured for electrical connection to a first semiconductor package (215) of a third half-bridge (205).

8. Busbar arrangement (305) according to claim 7, wherein the second busbar (615) has three parallel tabs (835, 840, 845), wherein the second, third and fourth load connection points (805 - 830) of the second busbar (615) are each assigned to a tab (805 - 830) and are formed on opposite sides of the respective tab (805 - 830) in order to electrically connect the second busbar (615) to a respective load connection (405, 410) of a first semiconductor package (215) of the respective half-bridge (205).

9. Busbar arrangement (305) according to one of the preceding claims, further comprising three third busbars (1300, 1305, 1310) arranged side by side in a third plane.

10. Busbar arrangement (305) according to one of the preceding claims, wherein at least one temperature sensor (1400) is arranged on at least one of the insulation films (900, 905, 910).

11. Busbar arrangement (305) according to one of the preceding claims, wherein a current sensor (1500) is arranged on at least one of the three first busbars (600, 605, 610).

12. Electronic power module (202) for a motor control (200), comprising a heat sink (300), three half-bridges (205) each having two semiconductor packages (215, 220) and a busbar arrangement (305) according to one of the preceding claims, which electrically connects the half-bridges (205) to one another.

13. Power module (202) according to claim 12 in conjunction with claim 7, further comprising a first connection element (310) for externally connecting a second semiconductor package (220) of the half-bridges (205).

14. The power module (202) according to claim 12 or claim 13 in conjunction with claim 7, further comprising a second connection element (315) for externally connecting the first load connection points (800) of the second busbar (615).

15. Electric drive axle (100), comprising an electric machine (125) and an electronic power module (202) according to one of claims 12 to 14.

16. Motor vehicle (105) comprising an electric drive axle (100) according to claim 15.

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