Power electronic sub-module with DC and AC voltage terminal components and its assembly

Abstract

The present invention discloses a power electronic sub-module having DC and AC voltage terminal components and its assembly, which includes a switching device having a substrate and printed conductors arranged thereon. The sub-module includes DC voltage printed conductors, and DC voltage terminal components are conductively connected to the DC conductors; AC voltage printed conductors, and AC voltage terminal components are conductively connected to the AC conductors. The sub-module further includes an insulating molding surrounding the switching device in a frame arrangement. The DC voltage terminal component engages a first support of the molding by a first contact section, and the AC voltage terminal component engages a second support of the molding by a second contact section. For this purpose, a first clamping device is configured to protrude through a first recess in the first support in an electrically insulating manner and form a conductive clamping connection between the DC voltage terminal component and the associated DC voltage connection member, and a second clamping device is configured to protrude through a second recess in the second support in an electrically insulating manner and form a conductive clamping connection between the AC voltage terminal component and the associated AC voltage connection member.

Description

Field of the Invention

[0001] The present invention describes a power electronic sub-module having a switching device. The substrate of the switching device includes first and second DC voltage printed conductors, and first and second DC voltage terminal elements are conductively connected to the first and second DC voltage printed conductors in the correct polarity. The substrate further includes an AC voltage printed conductor, and an AC voltage terminal element is conductively connected to the AC voltage printed conductor in the correct polarity. The switching device further includes a housing, which may also be configured as a sub-housing. The function of the DC voltage terminal element is preferably to provide a connection to a capacitor device, which is configured in the form of an intermediate circuit capacitor for a current converter module. Generally speaking, the function of the AC voltage terminal element is preferably to provide a connection to a motor or an electric machine. The present invention further describes an assembly having a sub-module or a plurality of sub-modules of this type, and having a support device for the sub-module, which support device may be specifically configured as a cooling device. Background Art

[0002] From the prior art, DE 102015114188A1 discloses a sub-module configured to have a substrate, a power semiconductor element, a connection device, a terminal device, and an insulating body. The substrate includes mutually electrically insulated printed conductors, wherein the power semiconductor element is arranged on one printed conductor and is conductively connected to the printed conductor. The connection device is configured as a composite foil structure and thus constitutes a first main surface facing the power semiconductor element and the substrate and a second main surface arranged opposite to the first main surface, wherein the sub-module is internally connected in the circuit by means of the connection device. The insulating body includes a first sub-body bonded to an edge of the substrate and further includes a first recess for a terminal element. The insulating body further includes a second sub-body configured as a pressure member and includes a second recess, in which a pressure element is arranged in a protruding manner. The first sub-body is connected to the second sub-body such that the second sub-body is arranged to move relative to the first sub-body in the direction of the substrate, such that the pressure element presses a section of the second main surface of the composite foil structure, which section is arranged to protrude within the surface of the power semiconductor element in the vertical direction of the power semiconductor element. Summary of the Invention

[0003] In view of the above prior art, an object of the present invention is to disclose a power electronic sub-module having a power conversion module, wherein the DC voltage terminal element and the AC voltage terminal element are arranged and configured in a particularly advantageous manner. Specifically, the arrangement has the advantage that it reduces the tensile load on the terminal element.

[0004] According to the invention, this object is achieved by a power electronic sub-module having the features of the invention and by the assembly according to the invention. Preferred forms of the embodiments are described in the respective description.

[0005] The power electronic sub-module according to the invention comprises a switching device having a substrate and printed conductors arranged on the substrate. The sub-module comprises: first and second DC voltage printed conductors, to which first and second DC voltage terminal elements are conductively connected in the correct polarity; and an AC voltage printed conductor, to which an AC voltage terminal element is conductively connected in the correct polarity. The sub-module further includes an insulating molding which surrounds the switching device in a frame-like arrangement. The first DC voltage terminal element engages with a first support of the insulating molding by means of a first contact section, and the AC voltage terminal element engages with a second support of the insulating molding by means of a second contact section. For this purpose, a first clamping device is configured to project through a first recess in the first support in an electrically insulating manner and to form a conductive clamping connection between the first DC voltage terminal element and the associated first DC voltage connection element, and a second clamping device is configured to project through a second recess in the second support in an electrically insulating manner and to form a conductive clamping connection between the AC voltage terminal element and the associated AC voltage connection element.

[0006] It is particularly advantageous if the first and second DC voltage terminal elements, together with an insulating device inserted therebetween, form a stacked arrangement at least in one section.

[0007] The corresponding clamping device can be configured to have a clamping element, preferably configured as a through-bolt and preferably having a spring device. The corresponding clamping device can also include an insulating sleeve through which the associated clamping element is routed. Preferably, the housing is made of a material from a group of materials including high-temperature plastics, in particular polyphenylene sulfide or polybutylene terephthalate.

[0008] Preferably, both the DC voltage terminal element and the AC voltage terminal element are made of metal foil or sheet metal, preferably having a thickness between 300 μm and 2040 μm, with a thickness between 500 μm and 1500 μm being particularly preferred.

[0009] Preferably, the first recess in the first support, the geometric midpoint of the switching device, and the second recess in the second support are arranged in a single row.

[0010] The component according to the invention comprises the above-mentioned power electronic sub-module and a support device, which is specifically configured as a cooling device. For this purpose, corresponding clamping devices, in particular corresponding bolts, are fixed in the support device, in particular by screwing, and at the same time, by means of a first clamping device, a conductive clamping connection is formed between the first DC voltage terminal element and the associated first DC voltage connection element, and likewise, by means of a second clamping device, a conductive clamping connection is formed between the AC voltage terminal element and the associated AC voltage connection element. The corresponding clamping devices simultaneously relieve the tensile load applied to the corresponding connection.

[0011] Particularly preferably, at the same time, by means of a first clamping device, a conductive clamping connection is formed between the second DC voltage terminal element and the associated second DC voltage connection element.

[0012] Further preferably, a pressure device is arranged above the switching device, which presses the switching device onto the support device, and a pressure loading device is arranged above the pressure device, which is attached by means of a clamping device such that the pressure is thus transmitted to the pressure device.

[0013] It may also be advantageous that a plurality of sub-modules having a common overall housing form a power module.

[0014] Naturally, unless explicitly excluded or excluded per se, features described in the singular, in particular the switching device, or features described in the context of the components of the sub-module may also exist in the plural in the sub-module according to the invention or in the said components.

[0015] It should be understood that in order to obtain improvements, various configurations of the invention can be implemented, either individually or in any desired combination. In particular, the above-mentioned features, as well as those identified or described hereinafter, whether they are described in the context of the sub-module or its components, can be employed not only in the indicated combinations, but also in other combinations or in isolation, without departing from the scope of the invention. Description of the Drawings

[0016] The advantageous features and characteristics of the invention are further elucidated from the following description of the exemplary embodiments of the invention or from the elements of the invention, and the exemplary embodiments of the invention are schematically presented in Figures 1 to 7 in.

[0017] Figures 1 to 4 Various elements of a first configuration of a component according to the invention, shown in a side sectional view, the component having a first configuration of a power electronic sub-module according to the invention.

[0018] Figure 5Illustrated is a second configuration of a component according to the invention, presented in a side sectional view, said component having a second configuration of a power electronics submodule according to the invention.

[0019] Figure 6 A three-dimensional representation of the power electronics submodule is shown.

[0020] Figure 7 A top view of the power electronics submodule is shown. Detailed Description

[0021] Figures 1 to 4 Illustrated are various elements of a first configuration of a component 1 according to the invention, presented in a side sectional view, said component 1 having a first configuration of a power electronics submodule 2 according to the invention. Figure 1 and Figure 2 and also Figure 3 and 4 The same sections are presented either in a partial exploded view or in the assembled state, respectively. In each case, the power electronics submodule 2 presents a switching device 4 arranged on a support device 3, which support device 3 is here configured as a cooling device, more particularly, and without loss of generality, as a fluid cooling device.

[0022] For the purpose of electrical insulation from and thermal coupling to the fluid cooling device 3, the switching device 4 comprises an insulating body 40, which is configured as a ceramic body 40. This ceramic body 40 comprises on the side thereof facing away from the fluid cooling device 3 a plurality of printed conductors 42, which are at different electrical potentials during operation of the switching device. One of these printed conductors 42, namely one of the plurality of DC voltage printed conductors, assumes a DC voltage potential. The submodule 2 in combination with the switching device 4 constitutes, for example, a power conversion circuit.

[0023] On at least one of the printed conductors which in combination with the insulating body 40 constitutes the substrate of the switching device 4, power semiconductor components 44 are arranged in a conventional manner and connected in the circuit. In this embodiment, this connection is configured as a conventional composite foil structure 48, which consists of alternately stacked conductive foils and electrically insulating foils.

[0024] For external connection, the power conversion module 2 (as presented in Figure 1 and 2 comprises two DC voltage terminal elements 50, 52, each of which is conductively connected to one of the DC voltage potential printed conductors 42 carrying a DC potential. In this case, this connection is conventionally and without loss of generality configured as a soldered connection.

[0025] The function of these DC voltage terminal components 50, 52 is to provide a connection to the associated DC voltage connection components 60, 62, which are preferably connected to the capacitor device.

[0026] In the region of the connection constructed by means of the first clamping device 7 between the DC voltage terminal components 50, 52 and the DC voltage connection components 60, 62, the first DC voltage terminal component 50 and the second DC voltage terminal component 52 form a stack, wherein, between the two DC voltage terminal components 50, 52, and only Figure 6 it is presented that an insulating device 54 is arranged. The first DC voltage terminal component 50 lies on the support surface 240 of the only partially presented housing 20 of the current conversion module 2. In this configuration, the housing 20 is only configured as a sub-housing and thus does not completely enclose the switching device 4, as is possible and also customary.

[0027] In this case, the housing 20 of the current conversion module 2 is constructed of a high-temperature-resistant plastic, in this case of polyphenylene sulfide, which additionally has a high flexural strength. The DC voltage terminal components 50, 52 are configured as thin metal sheets, more particularly, in this case, as copper sheets or copper sheets with surface coating treatment, which have a thickness of 700 μm. This insulating device 54 between the DC voltage terminal components 50, 52 is constructed of a plastic with high insulation tolerance, in this case, it is constructed of ethylene-tetrafluoroethylene copolymer or liquid crystal polymer, which has a thickness of 100 μm.

[0028] Figure 1 A cross-section of the first power electronic component 1 is shown in a cross-sectional view, wherein the cross-section extends through the plane in which the first clamping device 7 is also located. In addition to the above features, in this case, the first clamping device 7 and the DC voltage connection components 60, 62 are presented in an exploded view, while Figure 2 the first power electronic component 1 in the assembled state is shown.

[0029] In the connection region between the DC voltage terminal components 50, 52 and the DC voltage connection components 60, 62, as described, the first DC voltage terminal component 50 lies on the support surface 240 of the housing 20 and includes a recess 500.

[0030] The second DC voltage terminal component 52 is set back relative to the first DC voltage terminal component 50, with the result that the contact area of the second DC voltage terminal component with the second DC voltage connection component 62 (seen laterally and originating from the substrate) lacks the recess 500.

[0031] The respective contact areas of the DC voltage terminal elements 50, 52 are located on the respective sides transferred from the cooling device 3, while the respective contact areas of the DC voltage connection elements 60, 62 are each located on the respective sides facing the cooling device 3. Naturally, in the case of an alternative configuration, this entire arrangement can also be constructed as a mirror image.

[0032] The housing 20 includes a first recess 204 in the region of its first support surface 240, which is aligned with the recess 500 of the first DC voltage terminal element 50 in the z-direction. In this recess, and in the further recesses 500, 620 aligned therewith, including the recess of the AC voltage connection element 62, an insulating sleeve 74 is arranged, the function of which is the electrical insulation of the respective electrical potentials, including any necessary clearances and creepage distances. In this sleeve 74, a bolt 70 is arranged, and the bolt 70 in combination with a spring device 72 configured here as a disc spring constitutes a conductive clamping connection between the first DC voltage terminal element 50 and the first DC voltage connection element 60 and simultaneously between the second DC voltage terminal element 52 and the second DC voltage connection element 62. For this purpose, the bolt 70 is screwed into an internal threaded blind hole 32 in the cooling device 3, and the first clamping device 7 is fixed in the cooling device by means of this.

[0033] In this case, the above-mentioned components constitute the first clamping device 7 of the assembly. This configuration has several advantages. First, in terms of production technology, the arrangement of the DC voltage connection elements 60, 62 relative to the DC voltage terminal elements 50, 52 is particularly simple, because the stacked DC voltage connection elements 60, 62 only need to be arranged on the similarly stacked DC voltage terminal elements 50, 52, and an electrical connection with the correct polarity is constructed by means of a single threaded connection. The second significant advantage here lies in the attachment to the cooling device 3, which provides a significant reduction in the tensile load on the DC voltage connection elements 60, 62. In other words, with this configuration, any potential force acting on the substrates 40, 42 is prevented. In addition, the conductive connection thus constructed has a particularly low inductance.

[0034] For further external connection, the power conversion module 2 (as presented in Figure 3 and 4 ) includes an AC voltage terminal element 56, which is conductively connected to the AC voltage-carrying AC voltage potential printed conductor 46. In this case, this connection is conventionally and without loss of generality constructed as a soldering connection.

[0035] The function of the AC voltage terminal element 56 is to provide a connection to the associated AC voltage connection element 66, which is preferably connected to an electric motor. The AC voltage terminal element 56 is configured as a thin metal sheet, and more particularly, in this case, it is configured as a copper sheet or a copper sheet with a surface coating treatment, having a thickness of 700 μm.

[0036] Figure 3 A cross-section of the first power electronic assembly 1 is shown in a cross-sectional view, where the cross-section extends through the plane in which the second clamping device 8 is also located. In addition to the above features, in this case, the second clamping device 8 and the AC voltage connection element 66 are presented in an exploded view, while Figure 4 Figure 1 shows the first power electronic assembly 1 in the assembled state.

[0037] In the connection area between the AC voltage terminal element 56 and the AC voltage connection element 66, the AC voltage terminal element 56 is located on the support surface 260 of the housing 20 and includes a recess 560.

[0038] In this case, the contact area of the AC voltage terminal element 56 is on the side transferred from the cooling device 3 (see Figure 6 ), while the contact area of the AC voltage connection element 66 is on the side facing the cooling device 3. Naturally, in the case of an alternative configuration, this entire arrangement can also be configured as a mirror image.

[0039] The housing 20 includes a second recess 206 in the region of its second support surface 260, which is aligned with the recess 560 of the AC voltage terminal element aligned in the z direction. In all the aligned recesses 206, 560, 660 including the recess of the AC voltage connection element 66, an insulating sleeve 84 is arranged. In this sleeve 84, a bolt 80 is arranged, and the bolt 80 in combination with a spring device 82 configured as a disc spring here constitutes a conductive clamping connection between the AC voltage terminal element 56 and the AC voltage connection element 66. For this purpose, the bolt 80 is simply screwed into the internal threaded blind hole 34 in the cooling device 3, and the second clamping device 8 is fixed in the cooling device by means of this.

[0040] In this case, the above components constitute the second clamping device 8 of the assembly. This configuration basically serves the above advantages.

[0041] Figure 5 A second configuration of the assembly 1 according to the present invention is shown in a side cross-sectional view, and the assembly has a second configuration of the power electronic sub-module 2 according to the present invention. This configuration is in reference to Figures 1 to 4The described construction is basically the same, but additionally includes a substantially conventional pressure device 28, which includes a rigid pressure member 280 protruding in the direction of the switching device 4 and an elastic pressure element 282.

[0042] Indirectly, via the connecting device 48, the pressure element 282 applies pressure to the power semiconductor component 44. The main function of this pressure device 28 is the thermal connection between the switching device 4 and the cooling device 3.

[0043] In order to introduce the force required for this purpose, a pressure loading device 90 is constructed, which is designed to apply pressure to the side of the pressure device 28 that is transferred from the switching device 4, preferably centrally to the pressure device 28. For this purpose, the pressure loading device 90 is fixed or anchored by two clamping devices 7, 8, where the cooling device 3 serves as a counter-bearing. Here, the clamping devices are additionally constructed to perform Figures 1 to 4 the spring action of the disc springs 72, 82 presented in

[0044] The first and second clamping devices 7, 8 thus not only constitute the electrical connection between the terminal elements 50, 52, 54 and the connecting elements 60, 62, 64, but also constitute a significant thermal connection between the sub-module 2 and the cooling device 3.

[0045] Figure 6 A three-dimensional representation of the power electronic sub-module 2 is shown. Basically, this construction of the sub-module 2 is similar to the construction presented in Figure 5 but is presented in a structurally more precise manner compared to Figure 5 while Figure 5 outlines the design in a more schematic manner. The housing 20 of the power conversion module 2 is presented, which encloses the switching device 4 but does not cover the switching device 4. The switching device 4 is substantially covered by the pressure device 28, which presses the substrates 40, 42 against a non-presented cooling device 3, thus forming a thermal connection with the cooling device 3. In this case, to introduce pressure, an alternative pressure loading device 92 is provided. This includes a conventional central bolt that is screwed onto the cooling device and applies pressure to the pressure device via a disc spring.

[0046] The housing 20 includes a first coupling device 24 having a first support surface 240, and a first DC voltage terminal element 50 is arranged on the first support surface 240 in the terminal section. Here, as in Figure 5As shown in [reference], the contact surface of the first DC voltage terminal element 50 having the first DC voltage connection element is presented in cross - hatching. The first DC voltage terminal element 50 further includes a recess 500. The housing 20 includes a first recess 204 aligned with the recess 500. Both recesses are designed to accommodate a first clamping device in the form of an insulating sleeve, the first clamping device having a bolt passing through the insulating sleeve.

[0047] The insulating device 54 and the second DC voltage terminal element 52 are directly arranged on the first DC voltage terminal element 50 and together with this first DC voltage terminal element above the first support surface 240 form a stack. The second DC voltage terminal element 52 then has a contact surface with the second DC voltage connection element, which is presented in cross - hatching. The terminal section of the insulating device 54 recedes in the direction of the substrate relative to the terminal section of the first DC voltage terminal element 50. In addition, the terminal section of the second DC voltage terminal element 52 recedes in the same direction relative to the terminal section of the insulating device 54.

[0048] The housing 20 includes a second coupling device 26 having a second support surface 260, and the AC voltage terminal element 56 is arranged on the second support surface 260 in the terminal section. Here, as in Figure 5 As shown in [reference], the contact surface of the AC voltage terminal element 56 having the first AC voltage connection element is presented in cross - hatching. The AC voltage terminal element 56 further includes a recess 560. The housing 20 includes a recess 206 aligned with the recess 560, as in Figure 5 As shown in [reference]. Both recesses are designed to accommodate a second clamping device in the form of an insulating sleeve, the second clamping device having a bolt passing through the insulating sleeve.

[0049] Figure 7 Shows a top view of the power - electronic sub - module 2, presented without the housing and having substantially the same components as described in reference Figure 6 In this case, it is clearly shown that the first recess 204 of the first support element 24 and the recess 500 of the first DC voltage terminal element 50 aligned therewith, as well as the recess 520 of the second DC voltage terminal element 52, the geometric mid - point 400 of the switching device 4, the second recess 206 of the second support element 26 and the recess 560 of the AC voltage terminal element 56 aligned therewith are arranged on a virtual line. Additionally, it is advantageous that the pressure - loading device 90 according to Figure 5 exerts pressure on the pressure device in the normal direction, that is, perpendicular to the substrates 40, 40, and thus is aligned with the geometric mid - point 400.

Claims

1. A power electronic sub-module (2) having a switching device (4) with a substrate and comprising: first and second DC voltage printed conductors (42) to which first and second DC voltage terminal elements (50, 52) are conductively connected; and an AC voltage printed conductor (46) to which an AC voltage terminal element (56) is conductively connected in the correct polarity, and the power electronic sub-module (2) having an insulating molding (20) that encloses the switching device in a frame-like arrangement, wherein the first DC voltage terminal element (50) engages with a first support of the insulating molding (20) by means of a first contact section, wherein the AC voltage terminal element (56) engages with a second support (26) of the insulating molding (20) by means of a second contact section, wherein a first clamping device (7) is configured to project through a first recess in the first support in an electrically insulated manner and form a conductive clamping connection between the first DC voltage terminal element (50) and an associated first DC voltage connection element (60), and a second clamping device (8) is configured to project through a second recess (206) in the second support (26) in an electrically insulated manner and form a conductive clamping connection between the AC voltage terminal element (56) and an associated AC voltage connection element (66).

2. The sub-module according to claim 1, wherein the first and second DC voltage terminal elements (50, 52) form a stack with an intermediate insulating device (54).

3. The sub-module according to claim 2, wherein the insulating device (54) is constructed from a material in a group of plastic materials having a high insulation tolerance.

4. The sub-module according to one of the preceding claims, wherein the respective clamping devices (7, 8) are configured to have clamping elements.

5. The sub-module according to one of claims 1 - 3, wherein the respective clamping devices (7, 8) comprise insulating sleeves (74, 84) through which the clamping elements are guided.

6. The sub-module according to one of claims 1 - 3, wherein the housing (20) is constructed from a material in a group of materials including heat-resistant plastics.

7. The sub-module according to one of claims 1 - 3, wherein the DC voltage terminal elements (50, 52) and the AC voltage terminal element (56) are configured as metal foils or metal plates.

8. The sub-module according to one of claims 1 - 3, wherein the first recess in the first support, the geometric midpoint (400) of the switching device (4), and the second recess (206) in the second support (26) are arranged in a single row.

9. The sub-module according to claim 3, wherein the insulating device (54) is constructed from polyamide, ethylene-tetrafluoroethylene copolymer, or liquid crystal polymer.

10. The sub-module according to claim 3, wherein the insulating device (54) has a thickness of 50 μm to 500 μm.

11. The sub-module according to claim 3, wherein the insulating device (54) has a thickness of 5 μm to 150 μm.

12. The sub-module according to claim 4, wherein the clamping element is configured as through bolts (70, 80).

13. The sub-module according to claim 4, wherein the clamping element has spring means (72, 82).

14. The sub-module according to claim 6, wherein the housing (20) is made of polyphenylene sulfide or polybutylene terephthalate.

15. The sub-module according to claim 7, wherein the metal foil or metal plate has a thickness of 300 μm to 2040 μm.

16. The sub-module according to claim 7, wherein the metal foil or metal plate has a thickness of 500 μm to 1500 μm.

17. An assembly (1) having a sub-module (2) according to one of the preceding claims and having support means (3), wherein respective clamping means (7, 8) are fixed in the support means (3), and wherein, simultaneously, by means of the first clamping means (7), a conductive clamping connection is formed between the first DC voltage terminal element (50) and the associated first DC voltage connection element (60), and by means of the second clamping means (8), a conductive clamping connection is formed between the AC voltage terminal element (56) and the associated AC voltage connection element (66).

18. The assembly according to claim 17, wherein simultaneously, by means of the first clamping means (7), a conductive clamping connection is formed between the second DC voltage terminal element (52) and the associated second DC voltage connection element (62).

19. The assembly according to claim 17 or 18, wherein the support means (3) is configured as a cooling device.

20. The assembly according to one of claims 17 to 18, wherein a pressure means (28) is arranged above the switching means (4), the pressure means (28) pressing the switching means (4) against the support means (3), and wherein a pressure loading means (90) is arranged above the pressure means (28), the pressure loading means (90) being attached by means of the first and second clamping means (7, 8) such that pressure is thereby transmitted to the pressure means (28).

21. The assembly according to one of claims 17 to 18, wherein a plurality of sub-modules (2) having a common overall housing form a power module.

22. The assembly according to one of claims 17 to 18, wherein respective bolts are fixed in the support means (3).

23. The assembly according to claim 22, wherein, the respective bolts are fixed in the support means (3) by screwing.

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