Inverter arrangement

Abstract

Inverter arrangement comprising a housing (1) with a cooling circuit side (K) and a mounting space side (B) separated from it by a partition, and at least one component arranged in the area of ​​the mounting space side (B), which is at least one power semiconductor (3), wherein - the at least one power semiconductor (3) is directly attached to the partition of the housing (1), and - the partition of the housing (1) on the cooling circuit side (K) has a cooling structure (10) in the area of ​​the power semiconductor (3), wherein a printed circuit board (4) is arranged in the mounting space side (B) and is electrically and / or signal-wise connected to the power semiconductor (3), wherein capacitor foils of an intermediate circuit capacitor and busbars connected thereto are arranged in the mounting space side (B) and are directly mechanically connected to the partition of the housing (1) and electrically connected to the printed circuit board (4).

Description

The present invention relates to the field of electromobility, in particular to electronic modules for an electric drive. An inverter arrangement is provided. The use of electronic modules, such as power electronic modules, in motor vehicles has increased significantly in recent decades. This is due, on the one hand, to the need to improve fuel efficiency and vehicle performance, and on the other hand, to advances in semiconductor technology. The main component of such an electronic module is a DC / AC inverter, which serves to supply electrical machines such as electric motors or generators with multiphase alternating current (AC). In this process, direct current generated by a DC energy source (battery) is converted into multiphase alternating current. To this end, inverters comprise a variety of electronic components that implement bridge circuits (such as half-bridges), for example, semiconductor power switches, also known as power semiconductors. Currently, power semiconductor packages containing power semiconductors are sintered directly onto a copper plate, which is then connected to the inverter housing using screws and gaskets. A pin-fin structure is typically provided on the underside of the copper plate to transfer heat to the cooling water. This arrangement has several disadvantages, including the fact that mounting and sealing to the cooling circuit require installation space. This, in turn, can lead to various defects that may cause leaks and / or failures. DE 10 2014 015 827 A1 proposes an improved connection to the cooling circuit. DE 10 2008 001 028 A1, DE 10 2016 200 724 A1, and DE 10 2010 043 978 A1 also present solutions for improving cooling. The invention is based on the objective of providing an improved inverter arrangement. This task is solved by the features of independent claims. Advantageous embodiments are the subject of dependent claims. An inverter arrangement is proposed, comprising a housing with a cooling circuit side and a component side separated from it by a partition, as well as at least one component arranged in the component side, which is at least one power semiconductor, wherein the at least one power semiconductor is directly attached to the partition of the housing, and the partition of the housing on the cooling circuit side has a cooling structure in the area of ​​the power semiconductor. It is provided that a printed circuit board is arranged in the component side and electrically and / or signal-wise connected to the power semiconductor, wherein capacitor foils of an intermediate circuit capacitor and the associated busbars are arranged in the component side and are directly mechanically connected to the partition of the housing and electrically connected to the printed circuit board. In one embodiment, the cooling structure is additionally provided in areas where further components requiring cooling are located. In one embodiment, additional components to be cooled include a DC link capacitor and / or a printed circuit board and / or an EMC filter. In one embodiment, meandering channels are provided on the cooling circuit side, in which coolant is guided and the cooling structure is arranged. In one embodiment, the meandering channels are designed in such a way that the cooling fluid is supplied separately to each component to be cooled. In one embodiment, the power semiconductor is provided to be an IGBT package which has a mounting surface on one side with which it is attached to the partition wall of the housing. Furthermore, an electronic module is provided, comprising an inverter with the inverter arrangement for controlling the electric drive of a motor vehicle equipped with an electric drive. Furthermore, an electric drive of a vehicle is provided, comprising the electronic module for controlling the electric drive. Finally, a motor vehicle with the electric drive is provided. Further features and advantages of the invention will become apparent from the following description of exemplary embodiments of the invention, with reference to the figures in the drawing, which shows details of the invention, and from the claims. The individual features can be implemented individually or in any combination in a variant of the invention. Preferred embodiments of the invention are explained in more detail below with reference to the accompanying drawing. Fig. 1 shows a basic structure of an inverter arrangement according to the prior art. Fig. 2 shows a basic structure of an inverter arrangement according to an embodiment of the present invention. In the following figure descriptions, identical elements or functions are marked with the same reference symbols. As shown in Fig. 1, current inverters are designed such that the power semiconductor packages, i.e., the power semiconductors 3 arranged in a component package, e.g., IGBTs, are sintered onto a base plate 2 with one of their broad sides. The base plate 2 is typically made of copper. The copper plate is connected to the inverter housing 1 on the installation space side B by means of screws 21 and gaskets 2. On the underside of the copper plate, a cooling structure 20, usually formed as a pin-fin structure, is typically provided for transferring heat to the coolant 5 in the cooling circuit side K. The cooling structure 20 interrupts the partition wall of the housing 1 between the installation space side B and the cooling circuit side K. In the figures, only the partition wall is labeled with reference numeral "1" because the rest of the housing is not shown. The arrangement shown in Fig. 1 has several disadvantages, including the fact that mounting and sealing to the cooling circuit requires installation space. This, in turn, can lead to various defects that may result in leaks and / or failures. Therefore, the inverter arrangement described below with reference to the embodiment in Fig. 2 is proposed. It comprises a housing 1 with a cooling circuit side K and a component space side B separated from it by a partition (as part of the housing 1). The component space side B is the "dry" side in which the electrical components, e.g., one or more power semiconductors 3, are arranged. Coolant 5 is present in the area of ​​the cooling circuit side K to cool the components located in the component space side B, in particular the power semiconductors 3. To improve upon the disadvantages of the current inverter arrangement described above, it is proposed that the power semiconductors 3 be directly attached to (and thus mechanically connected to) the partition of the housing 1, thereby eliminating the base plate 2. This is advantageously achieved by connecting them to the partition of the housing 1 using their existing mounting surface, e.g., by sintering. Furthermore, the housing 1 (the partition) of the proposed inverter arrangement features a cooling structure 10 on the cooling circuit side K. This can be located solely in the area of ​​the power semiconductor 3, but also in the area of ​​other components requiring cooling, such as the DC link capacitor (assembly 6), a printed circuit board 4, or an EMC filter. This results in improved cooling performance for components located on the installation space side B. The proposed arrangement eliminates the previously required interface between power semiconductor 3, base plate 2, housing 1 and coolant 5. Consequently, a potential cause of failure is eliminated. In one embodiment, the cooling structure 10 of the inverter housing 1 is designed as a fin, preferably as a pin-fin structure. The fins projecting into the cooling circuit can be made very tall to compensate for the lower conductivity of aluminum (from which the housing 1 is normally made) compared to copper. Furthermore, the larger quantity of coolant 5 can even improve the cooling performance. In one embodiment, the coolant is guided by means of meandering channels such that areas of the partition wall of the housing 1, on which components requiring heat dissipation are located, are cooled separately. Such components include not only the power semiconductor 3, which must always be cooled, but also the DC link capacitor and / or a (populated) circuit board 4 and / or an EMC filter. The cooling structure 10 with its fins is then located within the meandering channels. This means that large parts of housing 1 (the partition) can be used for cooling purposes, whereby a meandering coolant flow allows for the separate cooling of individual components, resulting in more uniform cooling of the individual components. This also provides a more flexible cooling option for housing 1. Cooling can be further improved by attaching (mechanically connecting) parts of the intermediate circuit capacitor directly to the partition of the housing 1 (i.e., without an intermediate element other than, for example, an adhesive). Here, the capacitor foils and metal connections (busbars) are first bonded directly to the housing 1 (the partition), thus forming an assembly 6. Alternatively, a thermoset overmolding can be used. This overmolding can serve as an electrical insulating frame between the individual power semiconductors 3. Furthermore, the overmolding could contain the mounting elements for the circuit board 4, which must be electrically and signal-wise connected to the power semiconductors 3 (connection 34). The circuit board 4 is also electrically connected to the assembly 6 of capacitor foils and busbars via a contact 61. In one version, the cooling circuit side K of the housing 1 carries the connection nozzles for the coolant 5. In one embodiment, the at least one power semiconductor 3 is an IGBT package which has a mounting surface on one side of it with which it is attached to the partition wall of the housing 1, preferably by means of a sintering process according to the prior art. The proposed solution of the novel inverter arrangement provides a compact, vibration-resistant design. This allows for savings in both material and installation space, as well as increased production speed due to the reduced number of components required, and the elimination of interfaces. Furthermore, sealing measures between the copper plate and housing 1 are no longer necessary, since the copper plate (base plate 2) is no longer required. Additionally, the inverter arrangement is more adaptable, as the power semiconductors 3 can be flexibly placed in the housing 1 without having to adapt the design of the housing 1 and copper plate. The inverter assembly is part of an electronic module that, within the scope of this invention, serves to operate the electric drive of a motor vehicle, in particular an electric vehicle and / or a hybrid vehicle, and / or electrified axles. The electronic module comprises a DC / AC inverter. It may also include an AC / DC rectifier, a DC / DC converter, a transformer, and / or another electrical converter, or a part thereof. In particular, the electronic module serves to power an electric machine, for example, an electric motor and / or a generator. A DC / AC inverter preferably serves to generate a multiphase alternating current from a direct current generated by means of a DC voltage from an energy source, such as a battery. Reference symbol list 1 Housing 10 Cooling structure Housing 2 Base plate 20 Cooling structure Base plate 21 Screws 22 Gaskets 3 Power semiconductor, IGBT 34 Connection between 3 and 4 4 Circuit board 5 Coolant 6 Composite of capacitor films and busbars (DC circuit capacitor) 61 Contact between 4 and 6 K Cooling circuit side B Installation space side

Claims

Inverter arrangement comprising a housing (1) with a cooling circuit side (K) and a mounting space side (B) separated from it by a partition, and at least one component arranged in the area of ​​the mounting space side (B), which is at least one power semiconductor (3), wherein - the at least one power semiconductor (3) is directly attached to the partition of the housing (1), and - the partition of the housing (1) on the cooling circuit side (K) has a cooling structure (10) in the area of ​​the power semiconductor (3), wherein a printed circuit board (4) is arranged in the mounting space side (B) and is electrically and / or signal-wise connected to the power semiconductor (3), wherein capacitor foils of an intermediate circuit capacitor and busbars connected thereto are arranged in the mounting space side (B) and are directly mechanically connected to the partition of the housing (1) and electrically connected to the printed circuit board (4). Inverter arrangement according to claim 1, wherein the cooling structure (10) is additionally provided in areas where further components to be cooled are arranged. Inverter arrangement according to claim 2, wherein further components to be cooled are a DC link capacitor and / or a printed circuit board and / or an EMC filter. Inverter arrangement according to one of the preceding claims, wherein meandering channels are provided on the cooling circuit side (K) in which coolant is guided and the cooling structure (10) is arranged. Inverter arrangement according to claim 4, wherein the meandering channels are formed such that the cooling fluid is supplied separately to each component to be cooled. Inverter arrangement according to one of the preceding claims, wherein the power semiconductor (3) is an IGBT package having on one side a mounting surface with which it is attached to the partition of the housing (1). Electronic module comprising an inverter with an inverter arrangement according to one of the preceding claims for controlling the electric drive of a motor vehicle equipped with an electric drive. Electric drive of a vehicle, comprising an electronic module according to claim 7 for controlling the electric drive. Motor vehicle comprising an electric drive according to claim 8.

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