Busbar system

Abstract

In a busbar system (1), wherein the busbar system (1) comprises a first direct current busbar (3), a second direct current busbar (4) and an alternating current busbar (2), two of the three busbars (2, 3, 4) are arranged at least partially overlapping.

Description

Technical FieldThe invention relates to a bus bar system according to the preamble of claim 1.Prior ArtElectric vehicles frequently use batteries as energy stores which provide direct current. However, the electric motors that drive such electric vehicles are typically AC motors, for example, three-phase motors. For this reason, power electronic components are typically used in electric vehicles, with the aid of which the direct current provided by the batteries is converted into the alternating current required by the motors.This results in different challenges. On the one hand, this conversion of direct current into alternating current should proceed as energy-efficiently as possible, for example losses which can be caused, for example, by leakage inductances should be minimized. In addition, high power densities are desirable, for example in order to keep a space requirement for the power electronic elements in the vehicle low. Furthermore, such power electronic systems should be constructed as simply as possible in order to enable as simple as possible assembly and ideally to keep the system complexity as low as possible.When connecting different power electronic components in electric vehicles, what are known as bus bars are frequently used, which connect the power electronic components to one another in such a way that bridge circuits are realized, for example. However, the known busbar systems each have different disadvantages, for example with regard to their insufficiently high power density, their complicated construction or their energy efficiency. Instead of the term "busbar" originating from English, the purely german-language term "busbar" is used below. In other words, the terms "busbar" and "busbar" are used analogously and interchangeably in this patent application.GENERAL DESCRIPTION OF THE INVENTIONThe object of the invention is to eliminate or at least reduce the disadvantages of the prior art.The object is achieved by a busbar system, wherein the busbar system comprises a first direct current busbar, a second direct current busbar and an alternating current busbar, wherein two of the three busbars are arranged at least partially overlapping.A "busbar system" is to be understood here in particular as a system of electrical conductors which are typically at least sectionally plate-shaped or planar. Such a busbar system typically has different components, wherein the individual components themselves can be busbars or parts of busbars, for example. A "direct current busbar" is understood here to mean a busbar element which is suitable for conducting direct current. An "AC busbar" is understood here to mean a busbar element which is suitable for carrying AC current. By at least partially overlapping at least two of the three busbars, it can be achieved that a leakage inductance of the busbar system is reduced and a power density is increased, wherein in addition an assembly of the busbar system can be simplified because a stacking of busbar elements can enable a simpler connection to power electronic elements at least in some cases than if busbar elements are arranged next to one another.In advantageous embodiments, the first direct current busbar and the second direct current busbar and the alternating current busbar are arranged at least partially overlapping. Such an at least partial overlapping of all three busbars of the busbar system has the advantage that a particularly good reduction of a leakage inductance and a particularly high power density can thereby be achieved, at least in some embodiments. However, it is of course also possible that not all three busbars overlap at least partially, but that only two of the busbars overlap at least partially.In advantageous embodiments, the busbar system comprises a first insulation foil, wherein the first insulation foil preferably electrically isolates the first direct current busbar and / or the second direct current busbar and / or the alternating current busbar from one another. Such an insulating film is typically an electrically insulating plastic film which is ideally indeed electrically insulating, but on the other side is thermally conductive. Such an insulation film has the advantage that it can be arranged easily between two busbars and, for example, enables a compact construction of the busbar system. The first insulation film can be arranged, for example, between the first direct current busbar and the second direct current busbar. Furthermore, it is possible for the first insulation film to be arranged between the AC busbar and one of the two DC busbars. In this case, the first insulation film electrically isolates the busbars, between which it is arranged, from one another. Instead of an insulating film, however, it is also possible to use, for example, insulating lacquers or injection-molded parts.In advantageous embodiments, the busbar system comprises a second insulation film, wherein the second insulation film preferably electrically isolates the first direct current busbar and / or the second direct current busbar and / or the alternating current busbar from one another. Such an insulating film is typically an electrically insulating plastic film which is ideally indeed electrically insulating, but on the other side is thermally conductive. In advantageous embodiments, the busbar system thus comprises a first insulation film and a second insulation film, wherein two of the busbars are electrically insulated from one another by the first insulation film and wherein the second insulation film isolates an electrical insulation of the busbar already in contact with the first electrical setting film from the busbar, which has not previously been in contact with the first insulation film. In typical embodiments, the first insulation sheet is in contact with both the AC bus bar and the first DC bus bar and the second DC bus bar. In typical embodiments, the second insulation sheet is in contact with the AC bus bar and the first DC bus bar. In typical embodiments, the first insulation film and the second insulation film are arranged parallel to one another.In advantageous embodiments, the busbar system is constructed in sandwich construction. The term "sandwich construction" is understood here to mean that all busbars each comprise planar regions which are arranged at least partially or at least largely overlapping, wherein the first insulation film and / or the second insulation film is / are preferably arranged at least in places between the busbars.In typical embodiments, the busbar system comprises a plurality of receiving locations for semiconductor components, wherein the busbar system preferably comprises an even number of receiving locations for semiconductor components, in particular preferably at least two such receiving locations or at least four such receiving locations or at least six such receiving locations, wherein the receiving locations preferably all have an identical shape and / or wherein the receiving locations preferably have at least substantially a rectangular shape. The term "semiconductor components" is to be understood here as meaning, for example, electrical components which comprise at least one semiconductor element. The semiconductor components can be semiconductor packages, which each comprise a plurality of individual semiconductor components.In typical embodiments, the busbar system comprises a plurality of contact clips, wherein the contact clips are preferably suitable for contacting semiconductor components inserted into the receiving spaces from above when such semiconductor components are inserted into the receiving spaces, and / or wherein the AC busbar preferably comprises three or six or nine contact clips, or wherein the first DC busbar preferably comprises two or four or six contact clips and / or wherein the second DC busbar preferably does not comprise any contact clips. The term "contact clip" is typically understood to mean a typically metallic component which is suitable for establishing an electrical connection between a busbar on the one hand and a semiconductor component on the other hand.In advantageous embodiments, all of the contact clips of the first direct current busbar are arranged parallel to one another. In advantageous embodiments, the contact clips of the AC busbar are arranged parallel to the contact clips of the first DC busbar to one third and / or orthogonally to the contact clips of the first DC busbar to two thirds. The term "arranged parallel to one another" is to be understood here to mean that the contact clips each comprise longitudinal axes which run parallel to one another. Analogously, the term "orthogonal" is to be understood to mean that these longitudinal axes run orthogonally to one another. In advantageous embodiments, each contact clip comprises an electrically conductive metal sheet which comprises, for example, two flat regions and one bending region. In advantageous embodiments, the AC busbar is constructed in such a way that each semiconductor component inserted into a receiving location is contacted by exactly one or exactly two contact clips of the AC busbar when the semiconductor components are inserted into the receiving locations. In advantageous embodiments, the first DC busbar is constructed in such a way that exactly half of the receiving spaces are each assigned exactly two contact clips of the first DC busbar, wherein these two contact clips are typically arranged on opposite sides of the respective receiving spaces. The fact that the contact clips are suitable for contacting the semiconductor components from above also means that the contact clips typically do not contact the semiconductor components laterally. This saves space and the power loop of the busbar system is kept small, as a result of which the leakage inductance is likewise kept small.The object is furthermore achieved by a power electronics system comprising a busbar system according to at least one of the above-described exemplary embodiments, wherein the power electronics system preferably comprises at least one DBC, wherein the DBC preferably comprises an upper side, an underside and an insulation layer, wherein the underside preferably comprises a copper layer, wherein the upper side preferably comprises a conductive layer, wherein the upper side is preferably divided into a plurality of mutually insulated conductive areas, wherein a first region of the conductive areas is preferably conductively connected to the AC busbar and wherein a second region of the conductive areas is preferably conductively connected to the second DC busbar. The term "DBC" originates from English and stands for "Direct Bonded Copper", i.e. approximately "Directly Bonded Copper" for German persons skilled in the art, although the term "DBC" or also "DBC substrate" is typically used by German persons skilled in the art. In advantageous embodiments, the copper layer is a copper ceramic layer. In advantageous embodiments, the upper side comprises a first region which is conductively connected to the second direct current busbar. In advantageous embodiments, the upper side comprises a second region which is conductively connected to the AC busbar. In advantageous embodiments, the first region of the upper side is part of the second direct current busbar. In advantageous embodiments, the second region of the upper side is part of the AC busbar. In advantageous embodiments, the upper side is in contact with the first insulation film. In advantageous embodiments, the first insulation foil isolates the first region of the upper side from the first direct current busbar in regions. In advantageous embodiments, the first insulation foil electrically isolates the second region of the upper side from the first direct current busbar. In advantageous embodiments, the first direct current busbar is a negative direct current busbar. In advantageous embodiments, the second direct current busbar is a positive direct current busbar. In advantageous embodiments, the power electronics system is constructed in such a way that at least some, preferably all, of the contact clips are suitable for contacting at least one semiconductor component in each case from a side of the semiconductor component facing away from the DBC when such a semiconductor component is inserted into a receiving location. Instead of a DBC, in principle, it is also possible to use a different type of substrate for accommodating semiconductor components.In advantageous embodiments, the busbar system is mounted on the upper side of the DBC, wherein the first insulation foil preferably electrically isolates the upper side of the DBC from the first direct-current busbar and / or from the second direct-current busbar and / or from the alternating-current busbar.A "power electronics system" is to be understood here in particular quite generally as a technical system which is suitable for participating in a power electronic method and / or for accommodating at least one power electronic component.The object is furthermore achieved by a vehicle comprising a busbar system according to the invention and / or a power electronics system according to the invention.Brief Description of the DrawingsThe invention is briefly explained below with reference to drawings, in which: FIG. 1 : shows a schematic perspective view of a busbar system according to the invention in a first embodiment; FIG. 2 : a side view of the busbar system already shown in FIG. 1 ; FIG. 3 a : shows a schematic illustration of a cross-sectional profile through the busbar system shown in FIG. 1 ; FIG. 3 b : shows a schematic sectional view of the cross section illustrated in FIG. 3 athrough the busbar system shown in FIG. 1 ; FIG. 4 a : shows a schematic illustration of a section region from the cross section shown in FIG. 3 b; and FIG. 4b is an enlarged view of the detail shown in FIG. 4a.DESCRIPTION OF PREFERRED EMBODIMENTSFIG. 1 shows a schematic perspective view of a busbar system 1 according to the invention in a first embodiment. The busbar system 1 comprises an alternating current busbar 2 which, in the embodiment shown in FIG. 1, comprises a plurality of components. This is a reason why two lines of reference marks indicate different parts of the AC bus bar 2 in FIG. 1. The bus bar system 1 further includes a first DC bus bar 3. Also this first DC bus bar 3 includes a plurality of components in the embodiment shown in FIG. 1, which is a reason that the first DC bus bar 3 is provided with two reference marks. The busbar system 1 further comprises a second direct current busbar 4. in the embodiment shown in FIG. 1, the first direct current busbar 3 is a negative direct current busbar, that is to say a busbar which is suitable for being placed at a negative potential. In the exemplary embodiment shown in FIG. 1, the second direct-current busbar 4 is a positive busbar, which is therefore typically suitable for being placed at a positive potential. The busbar system 1 further comprises a first insulation film 5 and a second insulation film 6. The busbar system 1 forms together with the DBC 7 a power electronics system according to the invention. Alternatively, it is also possible to consider the DBC 7 as part of the bus bar system 1. Thus, if such an observation is made, the bus bar system 1 would include the DBC 7. The first insulation sheet 5 is disposed on a lower side of the bus bar system 1 and insulates the bus bar system 1 from the DBC 7. Specifically, the first insulation sheet 5 is disposed below the first DC bus bar 3. The second insulation sheet 6 is disposed between a part of the first DC bus bar 3 and a part of the AC bus bar 2. An area of the first insulation film 5 is more than twice as large as an area of the second insulation film 6. the AC busbar 2 comprises a total of six contact clips 8.1... 8.6. The first direct current busbar 3 comprises a total of four contact clips 9.1... 9.4. In addition, four semiconductor components 10.1... are shown in FIG. 1. 10.4. Each of these semiconductor devices 10.1... 10.4 is inserted into a receiving location of the busbar system 1. Semiconductor components 10.1... 10.4 are schematically shown as cuboidal elements. The receiving locations of the busbar system 1 are not themselves provided with reference symbols for the sake of better clarity. It is clear that each semiconductor component 10.1... 10.4 of a plurality of contact clips 8.1... 8.6, 9.1... 9.4, namely from above. In other words, the busbar system 1 is preferably constructed in such a way that the at least some of the contact clips 8.1... 8.6, 9.1... 9.4 Semiconductor Components 10.1... 10.4 are pressed into the respective receiving spaces.FIG. 2 shows a side view of the busbar system 1 already shown in FIG. 1. in particular, FIG. 2 once again shows the AC busbar 2, the first DC busbar 3 and the second DC busbar 4. It can also be seen that the alternating current busbar 2 and the first direct current busbar 3 comprise different components, which is also indicated in FIG. 2 by a plurality of reference marks. In FIG. 2, the first insulation film 5 and the second insulation film 6 can also be seen. Also shown in FIG. 2 is the DBC 7. In FIG. 2, the more precise structure of the DBC 7 can also be seen. The DBC 7 comprises in particular a bottom side 11 and a top side, wherein the top side comprises a first region 12 and a second region 13. A planar insulation layer 14 is arranged between the underside 11 and the upper side 12, 13. This insulation layer 14 is typically electrically insulating but thermally conductive. Furthermore, FIG. 2 shows the contact clip 8.3 of the AC busbar 2 and the contact clip 9.4 of the first DC busbar 3. In addition, it can be seen in FIG. 2 that the second direct current busbar 4 is fastened to the first region 12. It can also be seen in FIG. 2 that the AC busbar 2 is fastened to the second region 13. FIG. 2 also shows the contact clip 8.2 of the AC busbar 2. This contact clip 8.2 connects the second region 13 of the upper side of the DBC 7 to a part of the AC busbar 2. it can also be seen in FIG. 2 that the first insulation film 5 isolates the upper side of the DBC 7 from a lower side of the busbar system 1. It can also be seen that the second insulation film 6 is arranged between the AC busbar 2 and the first DC busbar 3 and electrically isolates the AC busbar 2 and the first DC busbar 3 from one another.FIG. 3 ashows a schematic representation of a cross-sectional course through the busbar system 1 shown in FIG. 1.FIG. 3 bshows a schematic view of the cross section indicated in FIG. 3 athrough the busbar system 1 shown in FIG. 1, and FIG. 3 b shows again the AC busbar 2 and the first DC busbar 3. Between the AC bus bar 2 and the first DC bus bar 3, the second insulation sheet 6 is disposed. This second insulation film 6 thus electrically isolates the AC busbar 2 from the first DC busbar 3. The insulation layer 14 is arranged between the underside 11 and the first region 12. The first region 12 is electrically connected to the second DC busbar 4, which is not visible in FIG. 3 b, however, on account of the cross-sectional view. The first insulation foil 5 is arranged between the first region 12 and the first direct current busbar 3. The first insulation foil 5 thus electrically isolates the first region 12 of the DBC from the first direct current busbar 3. Furthermore, the semiconductor components 10.3 and 10.4 are shown in FIG. 3b. The contact clips 8.3, 8.4 contact an upper side of the semiconductor component 10.3. The contact clips 8.5, 8.6 contact an upper side of the semiconductor component 10.4.FIG. 4 ashows a schematic representation of a section area from the cross section shown in FIG. 3 b. The cut-out region is represented in FIG. 4 a by a dashed quadrilateral.FIG. 4 bshows an enlarged illustration of the detail indicated in FIG. 4 a. FIG. 4 bthus again shows a part of the busbar system 1. Again, the AC bus bar 2 and the first DC bus bar 3 are shown. Between the AC bus bar 2 and the first DC bus bar 3, the second insulation sheet 6 is disposed. The contact clips 8.5, 8.6 of the AC busbar 2 can also be seen in FIG. 4 b. The section of the DBC already shown in FIG. 3 b, including the first region 12, the underside 11 and the insulation layer 14, is also shown. It can again be seen that the contact clips 8.5, 8.6 contact the semiconductor component 10.4 from above and thus press the semiconductor component 10.4 into its receiving location in the busbar system 1 (or in other words: fix it in its receiving location), wherein in each case one end of the contact clips 8.5, 8.6 is connected to the AC busbar 2 and wherein the respective other end of the contact clips 8.5, 8.6 contacts the semiconductor component 10.4 from above. FIG. 4 bfurther shows the first insulation film 5, which is arranged between the first region 12 of the upper side of the DBC on the one hand and the first direct current busbar 3.The invention is not limited to the described exemplary embodiments. The scope of protection is defined by the claims.Reference numerals denote reference numerals1 Bus bar system 2 AC bus bar 3 first DC bus bar 4 second DC bus bar 5 first insulation sheet 6 second insulation sheet 7 DBC 8.1... 8.6 Contact Clips of the Alternating Current Busbar 9.1... 9.4 Contact Clips of the First Direct Current Busbar 10.1... 10.4 Semiconductor devices 11 Bottom (of the DBC) 12 First region (the top side) 13 Second region (the top side) 14 Insulation layer

Claims

A busbar system (1), wherein the busbar system (1) comprises a first direct current busbar (3), a second direct current busbar (4) and an alternating current busbar (2), characterized in that two of the three busbars (2, 3, 4) are arranged at least partially overlapping.The busbar system (1) according to claim 1, characterized in that the first direct current busbar (3) and the second direct current busbar (4) and the alternating current busbar (2) are arranged at least partially overlapping.The busbar system (1) according to any one of the preceding claims, characterized in that the busbar system (1) comprises a first insulation foil (5), wherein the first insulation foil (5) preferably electrically isolates the first direct current busbar (3) and / or the second direct current busbar (4) and / or the alternating current busbar (2) from one another.The busbar system (1) according to claim 4, characterized in that the busbar system (1) comprises a second insulation foil (6), wherein the second insulation foil (6) preferably electrically isolates the first direct current busbar (3) and / or the second direct current busbar (4) and / or the alternating current busbar (2) from one another.Bus bar system (1) according to one of the preceding claims, characterized in that the bus bar system (1) is constructed in sandwich construction.Bus bar system (1) according to one of the preceding claims, characterized in that the bus bar system (1) has a plurality of receiving locations for semiconductor components (10.1... 10.4), wherein the busbar system (1) preferably comprises an even number of receiving locations for semiconductor components (10.1... 10.4), in particular preferably at least two such receiving spaces or at least four such receiving spaces or at least six such receiving spaces, wherein the receiving spaces preferably all have an identical shape and / or wherein the receiving spaces preferably have at least substantially a rectangular shape.Bus bar system (1) according to one of the preceding claims, characterized in that the bus bar system (1) comprises a plurality of contact clips, wherein the contact clips are preferably suitable for semiconductor components (10.1... inserted into the receiving spaces. 10.4) from above when such semiconductor components (10.1... 10.4) are inserted into the receiving spaces, and / or wherein the alternating current busbar (2) preferably has three or six or nine contact clips (8.1... 8.6) and / or wherein the first direct current busbar (3) preferably comprises two or four or six contact clips (9.1... 9.4) and / or wherein the second direct current busbar (4) preferably does not comprise any contact clips.Power electronics system comprising a busbar system (1) according to one of the preceding claims, characterized in that the power electronics system preferably comprises at least one DBC (7), wherein the DBC (7) preferably comprises an upper side, a lower side (11) and an insulation layer (14), wherein the lower side (11) preferably comprises a copper layer, wherein the upper side preferably comprises a conductive layer, wherein the upper side is preferably divided into a plurality of mutually insulated conductive areas (12, 13), wherein a first region (12) of the conductive areas (12, 13) is preferably conductively connected to the AC busbar (2) and wherein a second region (13 of the conductive areas (12, 13) is preferably conductively connected to the second DC busbar (4).Power electronics system according to Claim 8, characterized in that the busbar system (1) is mounted on the upper side of the DBC (7), wherein the first insulation foil (5) preferably electrically isolates the upper side of the DBC (7) from the first direct-current busbar (3) and / or from the second direct-current busbar (4) and / or from the alternating-current busbar (2).Vehicle comprising a busbar system (1) according to any one of claims 1 to 7 and / or a power electronics system according to any one of claims 8 to 9.

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