Power electronic submodules and method for arranging them on a cooling device

Abstract

The invention proposes a power electronic sub-module for mounting on a cooling device having a first surface section and a second surface section arranged next to one another, the sub-module having a base plate, a housing and a connection element, the connection element being in electrically conductive connection with a conductor track of the base plate with a contact section and having a connection section, the connection section being arranged parallel to the base plate, wherein the base plate is intended to be arranged on the first surface section with a first main face, wherein the housing has a housing section having a first main face for arrangement on the second surface section and a second main face opposite the first main face thereof, and wherein, in the state of the sub-module not being mounted, the first main face of the connection section is at a first distance from the second main face of the housing section in the housing area of a fixing device for mounting the housing section on the second surface section of the cooling device. The invention also proposes a method for mounting such a sub-module on a cooling device.

Description

TECHNICAL FIELD

[0001] A power electronics sub-module for mounting on a cooling device is described, the cooling device having a first surface section and a second surface section arranged next to each other, the power electronics sub-module comprising a base plate, a housing and a connection element, the connection element being in electrically conductive connection with a conductor track of the base plate by means of a contact section and having a connection section, wherein the base plate is intended to be arranged on the first surface section by means of a first main face. A method for arranging such a sub-module on a cooling device is also described. BACKGROUND

[0002] As prior art, DE 10 2017 115 883 A1 discloses a sub-module and a device comprising the same, wherein the sub-module has a switching device comprising a base plate and conductor tracks arranged thereon. The sub-module has a first DC voltage conductor track and a second DC voltage conductor track and a first DC voltage connection element and a second DC voltage connection element in electrically conductive connection therewith, and an AC voltage conductor track and an AC voltage connection element in electrically conductive connection therewith. The sub-module also has a profiled body of insulating material which surrounds the switching device in a frame-like arrangement. Here, the first DC voltage connection element is placed on a first support body of the profiled body of insulating material by means of a first contact section, and the AC voltage connection element is placed on a second support body of the profiled body of insulating material by means of a second contact section. A first clamping device is configured to extend through a first clearance in the first support body in an electrically insulating manner and to form an electrically conductive clamping connection between the first DC voltage connection element and the associated first DC voltage connection element, and a second clamping device is configured to extend through a second clearance in the second support body in an electrically insulating manner and to form an electrically conductive clamping connection between the AC voltage connection element and the associated AC voltage connection element. SUMMARY

[0003] In view of the prior art, it is an object of the present invention to propose a power electronics sub-module of the aforementioned general type, in which the thermal connection of the base plate to the cooling device is improved in the region of the connection of the contact section of the connection element to the conductor track of the base plate.

[0004] According to the application, this object is achieved by a power electronics sub-module for mounting on a cooling device, the cooling device having a first surface section and a second surface section arranged next to one another, the power electronics sub-module comprising a base plate, a housing and a connection element, the connection element being in electrically conductive connection with a conductor track of the base plate by means of a contact section and having a connection section, the connection section being arranged parallel to the base plate, wherein the base plate is provided for this purpose to be arranged on the first surface section by means of a first main face thereof, wherein the housing has a housing section, the housing section having a first main face for arrangement on the second surface section and a second main face opposite the first main face thereof, wherein in the state of the sub-module not being mounted, the first main face of the connection section is at a first distance from the second main face of the connection section in a housing area of a fixing device for mounting the housing section on the second surface section of the cooling device.

[0005] After the power electronics sub-module is mounted, in particular on the cooling device, in the housing area of the fixing device, the first main face of the connection section rests on or at a distance from the second main face of the housing section, the distance being smaller than the first distance. In this way, a pressure is exerted onto the contact section, as a result of which the thermal connection of the base plate to the cooling device is improved in the region of the connection of the contact section with the conductor track of the base plate. In this way, this region and the connection element itself are better cooled.

[0006] Here, the term "parallel to the base plate" is not to be understood precisely in the mathematical sense, but here also explicitly includes an angle of 10°, or at least an angle of 5°, between the connection section and the base plate.

[0007] For this purpose, it is advantageous if the connection element is configured as a flat metal body having at least one angled portion, and this angled portion or preferably a plurality of angled portions is configured in such a way that an angle is formed between the connection section and the base plate.

[0008] Additionally or alternatively, it is preferred if the housing section has a deformation element in the region of the second main face thereof, the deformation element interacting with the connection section and defining the first distance.

[0009] Here, the connection section has a pressure element, which is provided for this purpose to deform the deformation element when the sub-module is mounted.

[0010] For this purpose, the pressure element can protrude from the first main face of the connection section. Advantageously, this deformation element is configured in a cylindrical or frustoconical shape. It is also advantageous here if the base of the deformation element is arranged in a recess starting from the second main face of the housing section.

[0011] In principle, the fixing device can be configured as a screw, a rivet or a clamping-type fixing device.

[0012] According to the application, the above object is also achieved by a method for arranging a sub-module as described above on a cooling device, which has the following steps:

[0013] a) providing a sub-module and a cooling device, the cooling device having a first surface section and a second surface section which lie in one plane and do not overlap;

[0014] b) placing the sub-module on the cooling device, wherein the first main face of the base plate is placed on the first surface section and the first main face of the housing section of the housing of the sub-module is placed on the second surface section, wherein the first main face of the connecting section has a second spacing to the second surface section of the cooling device;

[0015] c) installing the fixing device;

[0016] d) forming a clamping connection between the connecting section and the cooling device, wherein the first main face of the connecting section has a third spacing to the second surface section after the clamping connection has been formed, the third spacing being smaller than the second spacing.

[0017] In the art, a layer of a thermally conductive substance, in particular a thermally conductive paste, is arranged between the first main face of the base plate and the first surface section.

[0018] As part of the method step d), preferably, the contact section is pressed onto the base plate and the base plate is pressed onto the first surface section of the cooling device.

[0019] It can be preferred that a section of the second main face of the housing section forms a support on which a sub-section of the connecting section is supported during the method step d), so that the pressure is exerted onto the base plate by means of the contact section.

[0020] It is particularly advantageous if the deformation element of the housing section is deformed by the pressure element of the connecting section. Here, it is advantageous if the deformation element protrudes from the second main face of the housing section and has a base which is arranged in a recess of the second main face of the housing section, wherein the base is partially or completely deformed into the recess during the method step d).

[0021] It goes without saying that features which are referred to in the singular in the sub-module according to the application, in particular the connecting element, can exist in a plurality, if this is not explicitly excluded or contradicted by the idea of the application. The individual method steps can also occur several times in the method according to the application or its flow.

[0022] It is to be understood that the various improvements of the present application, whether disclosed as part of a sub-module or method description or not, can be implemented individually or in any desired combination to achieve the improvements. In particular, the features mentioned and explained above and hereinafter can be used not only in the specified combinations, but also in other combinations or alone, without departing from the scope of the present application. Improvements. BRIEF DESCRIPTION OF DRAWINGS

[0023] Further embodiments, advantageous details and features of the present application result from the following description of an exemplary embodiment of the present application or its corresponding parts shown schematically in the drawings. Figures 1 to 9

[0024] Figure 1 Partially shown is a first improved embodiment of a power electronic sub-module according to the present application in an unmounted state and an exploded view of a cooling device.

[0025] Figure 2 Details in Figure 1 are shown.

[0026] Figure 3 Partially shown is a first improved embodiment of a power electronic sub-module according to the present application mounted on a cooling device.

[0027] Figure 4 Details in Figure 3 are shown.

[0028] Figure 5 Partially shown is a second improved embodiment of a power electronic sub-module according to the present application mounted on a cooling device.

[0029] Figure 6 Details in Figure 5 are shown.

[0030] Figure 7 Partially shown is a third improved embodiment of a power electronic sub-module according to the present application mounted on a cooling device.

[0031] Figure 8 A three-dimensional view of a part of the sub-module is shown.

[0032] Figure 9 A three-dimensional view of the sub-module according to the present application mounted on a cooling device is shown. DETAILED DESCRIPTION

[0033] Figure 1 Partially shown is a first improved embodiment of a power electronic sub-module 2 according to the present application in an unmounted state and an exploded view of a cooling device 3 designed as a liquid cooling device here. Figure 2 ​Details of the schematic are shown. On a first surface section 300 of the cooling device 3, a substrate 4 of a sub-module 2 is arranged. The substrate 4 is configured as usual with a body of insulating material 40 and conductor tracks 42 arranged thereon. On one of the conductor tracks 42, a power semiconductor component 44 is arranged and connected in a wiring specification with internal connection means 46. The connection means 46 are configured as a composite foil, which is common in the prior art.

[0034] On a second surface section 302 of the cooling device 3, which is arranged adjacent to the first surface section, a housing section 200 of the housing 20 is arranged (not shown here), see for example Figure 8 Such a housing 20 can itself encompass the entire sub-module 200, but can also be designed only as a partial housing and can also be a multipart design.

[0035] The housing section 200 has a first main face 210 arranged on the second surface section 302 and a second main face 220, which is opposite to the first main face and oriented parallel thereto. Furthermore, the housing section 200 has a gap 202, which leads from the second main face to the first main face, for the accommodation of the fixing means 7, or a part thereof.

[0036] The connection element 50, here more specifically the first DC load connection element, is designed as a flat metallic body with a contact section 510 and a connection section 500, the contact section 510 being in electrically conductive connection with the conductor track 42 of the substrate 4. The connection section 500 has a gap 504, which is aligned with the gap 202 of the housing section 200. In the gap 504, a part of the fixing means 7 is arranged in the mounted state. Here, a second DC load connection element 52 is also arranged parallel to the first DC load connection element. The two DC load connection elements 50, 52 jointly form an electrical connection to the capacitor 6, see Figure 9 , the connection elements 60, 62 of which are also shown here. The DC load connection elements 50, 52 are connected to the capacitor connection elements 60, 62 in a circuit-compatible manner by means of the fixing means 7.

[0037] Here, the fixing means 7 are configured as a screw 70, which engages into a threaded gap 76 of the cooling device 3. If necessary, a body of insulating material 74 for arrangement in the gap is also provided here for reasons of electrical insulation. A spring element 72, here a leaf spring, is also provided for the permanent and constant introduction of pressure.

[0038] According to the application, in the state in which the sub-module 2 is not mounted, the first main face 502 of the connection section 500, which faces the cooling device 3 and the housing section 200, has a first spacing 800 from the second main face 220 of the housing section 200 in the receiving area 204 of the fixing device 7. The receiving area 204 of the fixing device 7 is determined by the gap 202 of the housing section 200 and the environment immediately adjacent thereto.

[0039] In order to arrange the sub-module 2 on the cooling device 3, there is a second spacing 810 between the first main faces 502 of the connection sections 500 of the connection elements 50 in the receiving area 204 associated with the fixing device 7.

[0040] In order to reliably form the first spacing 800 and the second spacing 810, the housing section 200 has a deformation element 222 in the area thereof which, here, begins with the second main face 220, which deformation element cooperates with the connection section 500. The deformation element 222 has a substantially cylindrical shape, wherein the base of the deformation element 222 is arranged in the recess 226 of the second main face 220 of the housing section 200. This forms an angle between the plane of the base plate 4, more particularly the plane of the first main face 400 thereof, and the plane of the first main face 502 of the connection section 500 of the connection element 50, which angle is exaggerated here for the sake of clarity.

[0041] Figure 3 A first improved embodiment of the power electronics sub-module 2 according to the application is shown, which is mounted on the cooling device 3. Figure 4 Details are shown therein. Thus, the result of the method of arranging the sub-module 2 on the cooling device 3 is shown here.

[0042] By screwing the screw 70 of the fixing device 7 into the thread of the gap 76 of the cooling device 3, a portion of the connection section 500 deforms the deformation element 222 such that the deformation element 222 is deformed almost entirely into the recess of the housing section. This results in a significant reduction in the spacing between the first main face 502 of the connection section 500 and the second main face of the housing section 20 in the receiving area 204 of the fixing device 7 relative to the first spacing.

[0043] Advantageously, the connection element 500 is placed with its first main face 502 on the second main face 220 of the housing section 200, whereby, if technically feasible, the spacing between the two becomes zero.

[0044] The second spacing 810 of the unmounted device is likewise reduced, whereby a third spacing 812 is obtained, which is smaller than the second spacing.

[0045] Figure 5 A second improved embodiment of the sub-module 2 according to the application is shown, which is mounted on the cooling device 3.Figure 6 The details are shown. In this refinement, the fixing device 7 is in principle similar to the refinement according to Figure 1 and Figure 3 but the bearing of the screw here is a nut 78, which is not part of the cooling device.

[0046] A further difference to the arrangement according to Figure 1 and Figure 3 is the deformation element 224, which is configured here as a web, which is arranged in a recess of the housing section 200 and parallel to its second main face 220. The connection section 500 here has a clear pressure element 524, which is provided for this purpose such that the deformation element 224 is deformed as shown here when the sub-module 2 is installed.

[0047] In addition, a further part of the housing 20 is shown here. All other components correspond to the components according to Figures 1 to 4 .

[0048] Figure 7 A third refinement of the power electronics sub-module 2 according to the application, which is installed on the cooling device 3, is shown partially. The drawing shows the cooling device 3 and the base plate 4 as described above. But the connection element 500 here has a contact section 510, one bottom section of which is parallel to the base plate 4, in particular its first main face 400. Here, the entire connection element 5 has two angled sections, due to which the connection section 500 has an inclined profile in the direction of the cooling device 3. This inclined profile is here not assisted by any deformation element. The end of the connection section 500 is also in a recess of the housing section 200, which begins from the second main face 220 of the housing section.

[0049] In the course of the installation, the screw 70 is screwed into the thread of the gap 76 of the cooling device 3, as described above. Due to the forces that arise in the receiving area 204 of the fixing device 7, the connection section 500 is pressed in the direction of the second main face 220 of the housing section 200 and in the direction of the cooling device 3. At the same time, a pressure occurs on the connection section 510 of the connection element 50 and presses it onto the base plate 4 and onto the cooling device 3. Thus, a good heat transfer connection element 5 is provided here, which cools the entire connection element 5 during operation.

[0050] Figure 8 A part of the sub-module 2 is shown in a three-dimensional view, in which the above-mentioned details are also described in detail here. The housing 20 here has a plurality of partial housings, which are not directly connected to one another.

[0051] Figure 9A three-dimensional view of three sub-modules 2 according to the application mounted on a cooling device 3 is shown in a three-dimensional view. The capacitor 6 is also shown here. In the method according to the application, the connecting elements 60, 62 of the capacitor 6 are additionally connected to the connecting elements 50, 52 of the sub-modules 2 in a circuit-compatible manner.

Claims

1. A power electronics sub-module for mounting on a cooling device (3), the cooling device having a first surface section (300) and a second surface section (302) arranged next to each other, the power electronics sub-module comprising a base plate (4), a housing (20) and a connection element (50, 52), the connection element (50, 52) being in electrically conductive connection with a conductor track (42) of the base plate (4) by a contact section (510) and having a connection section, the connection section being arranged parallel to the base plate (4), wherein, The substrate (4) is provided for this purpose to be arranged on the first surface section (300) by the first main face (400), wherein the housing (20) has a housing section (200) with a first main face (210) for arrangement on the second surface section (302) and a second main face (220) opposite the first main face thereof, and wherein, in the state in which the sub-module (2) is not installed, the first main face (502) of the connection section (500) is at a first spacing (800) from the second main face (220) of the housing section (200) in a receiving region (204) of the fixing device (7) for installing the housing section (200) on the second surface section (302) of the cooling device (3), wherein the housing section (200) has a deformation element in the region of the second main face (220) thereof, which interacts with the connection section (500) and defines the first spacing (800).

2. The power electronic sub-module of claim 1, wherein, The connection element (50, 52) is configured as a flat metal body having at least one angled portion.

3. The power electronic sub-module of claim 1, wherein, The connection section (500) has a pressure element (524) for deforming the deformation element during installation of the sub-module.

4. The power electronics sub-module of claim 3, wherein, The pressure element (524) protrudes from the first main face (502) of the connection section (500).

5. The power electronics sub-module of claim 4, wherein, The deformation element is configured in a cylindrical or truncated conical shape.

6. The power electronics sub-module of claim 5, wherein, The base of the deformation element is arranged in a recess (226) starting from the second main face (220) of the housing section (200).

7. The power electronic sub-module of claim 1 or 2, wherein, The fixing device (7) is configured as a screw, a rivet or a clamping fixing device.

8. Method for arranging a power electronics sub-module according to any one of claims 1 to 7 on a cooling device (3), the method comprising the following steps: a) providing a sub-module (2) and a cooling device (3), the cooling device (3) having a first surface section (300) and a second surface section (302) which lie in one plane and do not overlap; b) placing the sub-module (2) on the cooling device (3), wherein the first main face (400) of the substrate (4) is placed on the first surface section (300) and wherein the first main face (210) of the housing section (200) of the housing (20) of the sub-module (2) is placed on the second surface section (302), wherein the first main face (502) of the connection section (500) has a second spacing (810) from the second surface section (302) of the cooling device (3); c) installing the fixing device (7); d) forming a clamping connection between the connection section (500) and the cooling device (3), wherein, after the clamping connection is formed, the first main face (502) of the connection section (500) has a third spacing (812) from the second surface section (302), which is smaller than the second spacing.

9. The method of claim 8, wherein, As part of the method step d), the contact section (510) is pressed onto the substrate (4) and the substrate is pressed onto the first surface section (300) of the cooling device (3).

10. The method according to claim 8 or 9, characterized in that, One section of the second main face (220) of the housing section (200) forms a support on which the relevant sub-section of the connection section (500) is supported during the method step d) and thus exerts a pressure onto the substrate (4) by means of the contact section (510).

11. The method according to claim 8 or 9, characterized in that, The deformation element of the housing section (200) is deformed by the pressure element (524) of the connection section (500).

12. The method of claim 11, wherein, The deformation element protrudes the second main face of the housing section and has a base which is arranged in a recess (226) of the second main face (220) of the housing section (200), wherein the base is partially or completely deformed into the recess (226) during the method step d).

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