Power electronics

Abstract

The utility model relates to a kind of power electronic devices.The power electronic device includes embedded power module, power capacitor, cooling chamber and connecting structure.Connecting structure includes electrically conductive column part, first end portion connecting part and second end portion connecting part, electrically conductive column part extends through the shell wall of power capacitor, cooling chamber and power module, first end portion connecting part is electrically connected to the copper exposed part of power module, and second end portion connecting part is electrically connected to the copper bar of power capacitor, and electrically conductive column part is provided with insulating layer at its outer periphery.The power electronic device of the utility model realizes the direct electrical connection of power capacitor and embedded power module by the electrically conductive column part through cooling chamber, reduces the space occupied, and the electrically conductive column part is cooled by the cooling medium flowing in cooling chamber.

Description

Technical Field

[0001] This utility model relates to the field of power conversion system technology for new energy vehicles, and in particular to a power electronic device. Background Technology

[0002] The power conversion systems of new energy vehicles, such as frequency converters, inverters, and converters, use semiconductor power modules to achieve functions such as changing the current frequency, converting DC to AC, and converting AC to DC.

[0003] Existing technologies, taking inverters as an example, such as Figures 1 to 4 The inverter shown typically includes multiple semiconductor power modules 1', capacitors 2', and a cooling chamber 3'. During power conversion, both capacitors 2' and semiconductor power modules 1' generate a significant amount of heat, which is typically dissipated through the flow of a cooling medium within the cooling chamber 3'. Therefore, the multiple semiconductor power modules 1' and capacitors 2' can be positioned on opposite sides of the cooling chamber 3'. A copper busbar 4' is located on the side of capacitors 2' facing away from the cooling chamber, extending from the side. A busbar (transition copper busbar) 5' is located on the side of the multiple semiconductor power modules 1' facing away from the cooling chamber 3', and copper pillars 6' (such as...) extend from the semiconductor power modules 1'. Figure 5 (As shown) is connected to busbar 5'. Busbar 5' extends from the side and is laser-welded to the copper busbar 4' of capacitor 2' on the side of cooling chamber 3'. This connection method for capacitor 2' and multiple power modules 1' is complex and occupies a large space. Cooling busbar 4' and copper busbar 5' is also a problem that urgently needs to be solved. Utility Model Content

[0004] The purpose of this utility model is to solve at least one of the above-mentioned problems and / or other problems existing in the prior art.

[0005] To achieve the above objectives, according to one aspect of the present invention, a power electronic device is provided, comprising an embedded power module, a power capacitor, and a cooling chamber sandwiched between the power module and the power capacitor. The power electronic device includes a connection structure for electrically and mechanically connecting the embedded power module and the power capacitor. The connection structure includes a conductive post portion and a first end connection portion and a second end connection portion disposed at the ends of the conductive post portion. The conductive post portion extends through the shell wall of the power capacitor, the cooling chamber, and the power module. The first end connection portion is electrically connected to an exposed copper portion formed on the side of the power module facing away from the cooling chamber, and the second end connection portion is electrically connected to a copper busbar of the power capacitor, thereby forming a conductive connection between the power capacitor and the power module. An insulating layer is disposed on the outer periphery of the conductive post portion.

[0006] According to one embodiment of the present invention, the cooling chamber is at least partially defined by a cooling substrate abutting against the power module, the conductive post portion extends through the cooling chamber and has an exposed section of the cooling medium flow path exposed within the cooling chamber, the conductive post portion is provided with a first groove for receiving a first sealing ring in the region through the cooling substrate, and a second groove for receiving a second sealing ring in the region through the shell wall of the power capacitor.

[0007] According to one embodiment of the present invention, the insulating layer is formed on the outer periphery of the conductive post portion in a plastic-coated manner.

[0008] According to one embodiment of the present invention, the conductive post portion is mechanically connected to the second end connection portion via a threaded connection and electrically connected to the copper busbar of the power capacitor.

[0009] According to one embodiment of the present invention, the conductive post portion has a threaded blind hole along the axial direction at its end near the copper busbar of the power capacitor.

[0010] According to one embodiment of the present invention, the second end connection portion includes a double-ended stud portion that is partially screwed into the threaded blind hole. The second end connection portion also includes a nut with an internal threaded hole welded to the copper busbar of the power capacitor on the side opposite to the cooling chamber. The end section of the double-ended stud portion extending from the conductive post portion extends through the copper busbar of the power capacitor and is screwed into the internal threaded hole of the nut, such that the copper busbar of the power capacitor is sandwiched between the nut and the conductive post portion.

[0011] According to one embodiment of the present invention, the first end connection portion is configured as an end flange integrally extending from the conductive post portion, and the end flange abuts against and connects with the exposed copper portion of the power module.

[0012] According to one embodiment of the present invention, the end flange is formed as a hexagonal prism head.

[0013] According to one embodiment of the present invention, the power capacitor includes a DC-link capacitor.

[0014] According to one embodiment of the present invention, the power electronic device includes an inverter or a frequency converter.

[0015] The power electronic device of this invention allows the conductive post portion of the connecting structure to extend through the embedded power module, cooling chamber, and the shell wall of the power capacitor. It forms a conductive connection between the power capacitor and the embedded power module by electrically connecting the first end portion to the exposed copper portion of the embedded power module and the second end portion to the copper busbar of the power capacitor. This eliminates the need for busbars and copper posts in existing technologies, achieving a direct electrical connection between the power capacitor and the embedded power module through the conductive post portion passing through the cooling chamber, thus reducing space requirements. Furthermore, the heat generated by the embedded power module and the power capacitor can be conducted to the conductive post portion through the exposed copper portion and the copper busbar, respectively, and then carried away by the cooling medium flowing within the cooling chamber, along with the heat generated on the conductive post portion, thereby cooling the entire device. Attached Figure Description

[0016] The features and advantages of this utility model will become clear from the following detailed description provided with reference to the accompanying drawings. It should be understood that the following drawings are merely schematic and not necessarily drawn to scale, and therefore should not be considered as limitations on this utility model, wherein:

[0017] Figure 1 An exploded view of a power electronic device according to the prior art is shown.

[0018] Figure 2 Show Figure 1 A three-dimensional diagram of the power electronic device shown.

[0019] Figure 3 Show Figure 2 The diagram shown is a three-dimensional view of the power electronic device without the busbars.

[0020] Figure 4 Show Figure 2 A partially enlarged view of the power electronic device shown.

[0021] Figure 5 Show Figure 2 Another enlarged view of the power electronic device shown.

[0022] Figure 6 A perspective view of a power electronic device according to an embodiment of the present invention is shown.

[0023] Figure 7 An exploded view of a power electronic device according to an embodiment of the present invention is shown.

[0024] Figure 8 A top view of a power electronic device according to an embodiment of the present invention is shown.

[0025] Figure 9This diagram illustrates an embedded power module electrically connected to a power capacitor via a connection structure in a power electronic device according to an embodiment of the present invention.

[0026] Figure 10 A schematic diagram showing a portion of the connection structure of a power electronic device according to an embodiment of the present invention. Detailed Implementation

[0027] Embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, numerous specific details are set forth to enable those skilled in the art to more fully understand and implement the present invention. However, it will be apparent to those skilled in the art that implementations of the present invention may not include some of these specific details. Furthermore, it should be understood that the present invention is not limited to the specific embodiments described. Rather, the present invention can be conceived to be implemented with any combination of the features and elements described below, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments, and advantages are for illustrative purposes only and should not be construed as elements or limitations of the claims unless expressly set forth in the claims.

[0028] The terms "first" and "second" are used below to describe the elements of this application. These terms are used only to distinguish the individual elements and not to limit the nature, order, or number of these elements. The terms "comprising" and "having" are used to indicate an open-ended inclusion and mean that there may be additional elements / components besides those listed.

[0029] Figure 6-10 A power electronic device according to an embodiment of the present invention is shown. For example... Figures 6 to 10 As shown, the power electronic device according to this embodiment may include an embedded power module 1, a power capacitor 2, and a cooling chamber 3 sandwiched between the embedded power module 1 and the power capacitor 2. The embedded power module 1 may include a module substrate 12 and power devices embedded in the module substrate. The power capacitor 2 may include a capacitor bank consisting of multiple capacitor cells, a copper busbar 21 electrically connecting the capacitor cells, and a housing 22 defining a cavity accommodating the capacitor bank and the copper busbar 21. In the illustrated embodiment, the cooling chamber 3 is defined by the upper shell wall of the cooling substrate 11, which is adjacent to the power module, and the housing of the power capacitor. For example, the cooling substrate 11 defines the top wall of the cooling chamber 3, and the upper shell wall of the housing 22 of the power capacitor 2 defines the bottom wall of the cooling chamber 3.

[0030] It is understood that the embedded power module 1 in this article refers to a multilayer substrate in the form of a PCB board in which semiconductor chips or power devices of a power module are embedded. A circuit layer with copper-clad and buried copper portions is formed on one side or opposite sides of the multilayer substrate. Unlike traditional packaged power modules, the embedded power module 1 has higher integration and power density, not only reducing the space occupied by the package but also allowing for heat dissipation through the formed copper-clad and buried copper portions, thereby improving electrical performance and heat dissipation efficiency.

[0031] The power electronic device according to this utility model may further include a connection structure 4, which can electrically connect the power module 1 and the power capacitor 2, and can mechanically connect the power module 1 and the power capacitor 2 to opposite sides of the cooling chamber 3.

[0032] The module substrate 12 has an exposed copper portion 13 formed on its side opposite to the cooling substrate 11. The connection structure 4 may include a conductive pillar portion 41, a first end connection portion 42, and a second end connection portion 43. The conductive pillar portion 41 is generally columnar and has two ends, passing through the shell walls of the embedded power module 1, the cooling chamber 3, and the power capacitor. The first end connection portion 42 is disposed at the first end of the conductive pillar portion 41, and the second end connection portion 43 is disposed at the second end of the conductive pillar portion. The first end connection portion 42 and the second end connection portion 43 are electrically connected to the exposed copper portion 13 of the embedded power module 1 and the copper busbar 21 of the power capacitor 2, respectively, thereby forming an electrical connection between the power capacitor 2 and the embedded power module 1. An insulating layer 44 is covered around the outer periphery of the conductive pillar portion 41 to isolate the conductive pillar portion 41 from the cooling medium flowing through the cooling chamber 3, achieving high-voltage insulation (isolating high-voltage components from low-voltage components) and preventing leakage.

[0033] refer to Figures 6 to 10 As shown, the conductive post portion 41 of the connecting structure 4 may include an exposed section 45. The exposed section 45 is exposed to the cooling medium flow path within the cooling chamber 3. The section 46 of the conductive post portion 41 that penetrates the cooling substrate 11 is provided with a first groove 48 extending circumferentially therein. A first sealing ring 6 is received within the first groove 48 and elastically abuts against the wall of the through hole 111 of the cooling substrate 11 to prevent the cooling medium from leaking from the gap between the conductive post portion 41 and the cooling substrate 11. Similarly, the section 47 of the conductive post portion 41 that penetrates the shell wall 22 of the power capacitor 2 is provided with a second groove 49 extending circumferentially therein. A second sealing ring 7 is received within the second groove 49 and elastically abuts against the wall of the cylindrical orifice 221 of the shell wall 22 of the power capacitor 2 to prevent the cooling medium from leaking from the gap between the conductive post portion 41 and the shell wall 22.

[0034] In this embodiment, the first end connection portion 42 is integrally formed on the upper end (first end) of the conductive post portion 41 to form an end flange integrally extending from the conductive post portion 41. The first end connection portion 42 is abutted and connected to the exposed copper portion 13 of the embedded power module 1.

[0035] The conductive post portion 41 forms an electrical connection and a detachable mechanical connection with the second end connection portion via a threaded connection. Figure 9 In the specific embodiment shown, the conductive post portion 41 has a threaded blind hole 411 extending axially at its lower end (second end) opposite to the first end connection portion 42, and the second end connection portion 43 may include a double-ended stud portion 431. The first end section of the double-ended stud portion 431 is screwed into the threaded blind hole 411, and the second end section extends out from the conductive post portion 41 and passes through a perforation on the copper busbar 21 of the power capacitor 2.

[0036] The second end connection portion 43 may also include a nut 432 with an internally threaded hole welded to the side of the copper busbar 21 of the power capacitor 2 facing away from the cooling chamber 3. The second end section of the double-ended stud portion 431 passes through a hole in the copper busbar 21 and is screwed into the internally threaded hole of the nut 432, thereby clamping the copper busbar 21 of the power capacitor 2 between the nut 432 and the conductive post portion 41. By configuring the second end connection portion 43 to include the double-ended stud portion 431 installed in the conductive post portion 41 and the nut 432 fixed to the copper busbar 21 by welding, it is convenient and simple to assemble, and avoids the trouble caused by the limited space under the copper busbar 21.

[0037] Although Figures 6 to 10 In the illustrated embodiment, the conductive post portion 41 is threadedly connected to the nut 432 via a double-ended stud portion 431. However, it is understood that the threaded connection between the conductive post portion 41 and the second end connection portion 42 is not limited to the illustrated embodiment. For example, the double-ended stud portion 431 and the nut 432 can be replaced with a screw portion having an end flange and extending from a hole on the copper busbar of the power capacitor integral with the end flange. Alternatively, the second end connection portion 43 can be designed with nuts welded to both sides of the copper busbar 21 of the power capacitor, and the end of the conductive post portion 41 near the copper busbar of the power capacitor can be designed with an external threaded section that can pass through the hole on the copper busbar 21 of the power capacitor and mate with the internal threaded hole of the nut welded to both sides of the copper busbar. This forms a tight mechanical connection and an electrical connection achieved by the mechanical connection between the conductive post portion and the second end connection portion.

[0038] The insulating layer 44 is formed on the outer periphery of the conductive post portion 41 in a plastic-coated manner, effectively preventing electrical contact between the conductive post portion 41 (especially the exposed section 45) and the cooling medium flowing in the cooling chamber 3. This allows for the formation of an effective current path (e.g., between the copper busbar 21 of the power capacitor 2, the conductive post portion 41, the first end connection portion 42, and the exposed copper portion 13 of the power module 1) Figure 9 (As indicated by the middle arrow).

[0039] In this embodiment, for ease of processing, the conductive post portion 41 and the end flange (i.e., the first end connection portion 42) are integrally made of copper, and the double-ended stud portion 431 is made of steel. The end flange is formed into a hexagonal head, which facilitates tightening with a hexagonal tool.

[0040] When assembling the power electronic device according to this utility model embodiment, the following steps can be followed:

[0041] The connection structure 4 is provided as follows: a blank of conductive post portion 41 with end flange, first groove 48 and second groove 49 formed by cold heading; a threaded blind hole 411 extending axially along the conductive post portion is formed at the end (second end) of the conductive post portion 41 away from the end flange by machining; an insulating layer 44 is applied to the outer periphery of the conductive post portion 41 by plastic coating; the first end section of the double-ended stud portion 431 is screwed into the threaded blind hole 411 of the conductive post portion 41; and the first sealing ring 6 and the second sealing ring 7 are respectively installed into the first groove 48 and the second groove 49 of the conductive post portion 41.

[0042] Weld the nut 432 to the side of the copper busbar 21 of the power capacitor 2 away from the cooling chamber 3, and align the internal thread hole of the nut with the through hole on the copper busbar.

[0043] The shell wall 22 of the power capacitor 2, the cooling substrate 11 and the module substrate 12 in which the power device is embedded are stacked and assembled in sequence, and the cylindrical opening 221 of the shell wall 22, the through hole 111 of the cooling substrate 11, the through hole of the module substrate 12 and the through hole of the copper busbar 21 are aligned.

[0044] The conductive post portion 41 with the sealing ring is extended through the aligned hole, and the second end section of the double-ended stud portion 431 extending from the conductive post portion passes through the through hole on the copper busbar 21 and is screwed into the nut 432, so that the end face of the conductive post portion 41 abuts against the copper busbar 21, and the first end connection portion 42 in the form of an end flange abuts against the exposed copper portion 13 of the embedded power module 1.

[0045] Therefore, according to this embodiment of the invention, mechanical and electrical connections can be completed simply by using a screw-type conductive post 41 to pass through the stacked module substrate, cooling substrate, and power capacitor housing wall and screw it into the nut 432, making the operation simple and reliable. Furthermore, this results in a more compact lateral structure for the entire power electronic device. The heat dissipation capacity of the entire device is further improved compared to the conductive post being directly flushed by the cooling medium.

[0046] In the above embodiments, the power capacitor 2 can be a DC-link capacitor. The power electronic device can be configured as an inverter or a frequency converter. For example, when multiple power modules are configured as high-side switches or low-side switches respectively, the power electronic device can be used as an inverter by connecting the DC-link capacitor between the high-side switch and the low-side switch.

[0047] Compared to existing power electronic devices, the power electronic device according to the present invention can extend through the shell wall 22, cooling chamber 3, and embedded power module 1 of the connecting structure via the conductive post portion 41. It is electrically connected to the exposed copper portion 13 of the embedded power module 1 via the first end connecting portion 42, and electrically connected to the copper busbar 21 of the power capacitor 2 via the second end connecting portion 43, thus forming an electrical connection between the power capacitor 2 and the embedded power module 1. This eliminates the need for busbars (transfer copper busbars) and copper posts in the prior art, achieving a direct electrical connection between the power capacitor 2 and the embedded power module through the conductive post portion 41 passing through the cooling chamber 3, reducing space requirements. Furthermore, the heat generated by the embedded power module 1 and the power capacitor 2 can be additionally conducted to the conductive post portion 41 through the exposed copper portion 13 and the copper busbar 21, and carried away by the cooling medium flowing within the cooling chamber 3, thereby achieving a better cooling effect.

[0048] Various modifications and variations can be made to the embodiments disclosed above without departing from the scope or spirit of this invention. Other embodiments of this invention will be apparent to those skilled in the art based on the practice of this invention disclosed in this specification. This specification and the examples disclosed herein should be considered illustrative only, and the true scope of this invention is defined by the appended claims and their equivalents.

Claims

1. A power electronic device, characterized in that, include: Embedded power module; Power capacitors; as well as The cooling chamber sandwiched between the power module and the power capacitor, The power electronic device includes a connection structure for electrically and mechanically connecting an embedded power module and a power capacitor. The connection structure includes a conductive post portion and a first end connection portion and a second end connection portion disposed at the ends of the conductive post portion. The conductive post portion extends through the casing wall of the power capacitor, the cooling chamber, and the power module. The first end connection portion is electrically connected to an exposed copper portion formed on the side of the power module facing away from the cooling chamber. The second end connection portion is electrically connected to the copper busbar of the power capacitor, thereby forming a conductive connection between the power capacitor and the power module. The conductive post portion has an insulating layer on its outer periphery.

2. The power electronic device according to claim 1, characterized in that, The cooling chamber is at least partially defined by a cooling substrate abutting the power module. The conductive post extends through the cooling chamber and has an exposed section that exposes the cooling medium flow path within the cooling chamber. The conductive post has a first groove for receiving a first sealing ring in the region through the cooling substrate and a second groove for receiving a second sealing ring in the region through the casing wall of the power capacitor.

3. The power electronic device according to claim 2, characterized in that, The insulating layer is formed on the outer periphery of the conductive post portion in a plastic-coated manner.

4. The power electronic device according to claim 3, characterized in that, The conductive post portion is mechanically connected to the second end connection portion via a threaded connection and electrically connected to the copper busbar of the power capacitor.

5. The power electronic device according to claim 4, characterized in that, The conductive post portion has a threaded blind hole along its axial direction at the end near the copper busbar of the power capacitor.

6. The power electronic device according to claim 5, characterized in that, The second end connection portion includes a double-ended stud portion that is partially screwed into the threaded blind hole. The second end connection portion also includes a nut with an internally threaded hole welded to the copper busbar of the power capacitor on the side opposite to the cooling chamber. The end section of the double-ended stud portion extending from the conductive post portion extends through the copper busbar of the power capacitor and is screwed into the internally threaded hole of the nut, such that the copper busbar of the power capacitor is sandwiched between the nut and the conductive post portion.

7. The power electronic device according to claim 6, characterized in that, The first end connection portion is configured as an end flange integrally extending from the conductive post portion, and the end flange abuts against the exposed copper portion of the power module.

8. The power electronic device according to claim 7, characterized in that, The end flange is formed into a hexagonal prism head.

9. The power electronic device according to any one of claims 1 to 8, characterized in that, The power capacitors include DC-link capacitors.

10. The power electronic device according to any one of claims 1 to 8, characterized in that, The power electronic device includes an inverter or a frequency converter.

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