Power module, electrical device and method for manufacturing a power module

Abstract

The invention relates in particular to a power module (1) having an AC connection side (2) and a DC connection side (3) opposite the AC connection side (2), the power module (1) further comprising:-a printed circuit board (4),-at least one AC connection (AC) arranged on the AC connection side (2), and-at least three DC connections (DCP, DCM, DCN), the direct current connections comprise one or more intermediate direct current connections (DCM) and two external direct current connections (DCP, DCN), the external direct current connections comprise a positive direct current connection (DCP) and a negative direct current connection (DCN), one of the intermediate direct current connections (DCM) and one of the external direct current connections (DCP, DCN) being arranged on the direct current connection side (3) and outside the printed circuit board (4) in plan view. In order to provide, in particular, an improved power module (1), the respective remaining DC connections (DCP, DCM, DCN) are arranged between the AC connection side (2) and the DC connection side (3) and in the region of the printed circuit board (4) in plan view, in particular in the region of a transistor module (20) of the power module (1).

Description

Technical Field

[0001] The present invention relates to a power module, which has an AC connection side and a DC connection side opposite to the AC connection side, wherein the power module also includes a printed circuit board, at least one AC connection arranged on the AC connection side, and at least three DC connections, the DC connections including one or more intermediate DC connections and two external DC connections, the external DC connections including a positive DC connection and a negative DC connection, wherein one of the intermediate DC connections and one of the external DC connections are each arranged on the DC connection side and arranged outside the printed circuit board in a plan view.

[0002] The invention also relates to a corresponding electrical device, each having at least one such power module.

[0003] Finally, the invention relates to a method for producing such a power module. Background Art

[0004] Such a device or such a method is used in a variety of applications in power electronics. For example, semiconductor components are used in power electronics in order to operate better in a housing with external connection technology, such as an IGBT module, wherein the IGBT is an insulated gate bipolar transistor. In the case of lower power, the joint is led out of the housing as a soldering pad, which is often called a package. In the case of higher power, a threaded joint with a larger bearing surface is used in order to connect other connections, such as internal busbars, thereto. Like all other components in power electronics, high requirements are also placed on the IGBT module. For example, the present invention can be applied to the threaded connection technology of higher power IGBT modules, in particular for the IGBT module "EconoDual3" from Infineon Technologies AG, Munich, "SEMiX" from SEMIKRON Elektronik GmbH & Co. KG, Nuremberg or "SD3" from Siemens AG, Munich.

[0005] The above-described IGBT modules are used in particular for applications in 2-level technology, for example in order to realize a single half-bridge consisting of a plurality of individual IGBT semiconductors.

[0006] A power semiconductor module with four power connections is known from US Pat. No. 8,847,328 B1. The IGBT has a collector connected to a first power connection and an emitter coupled to a third power connection. An antiparallel diode is coupled in parallel to the IGBT. A DC voltage connection is connected between the second and fourth power connections. The DC link may comprise two diodes and two IGBTs, wherein the IGBTs are connected to a common collector in one configuration. The first and second power connections are arranged on a first line along one side of the module and the third and fourth power connections are arranged on a second line along an opposite side of the module. Two identical instances of the module can be interconnected to form a three-level NPC phase branch with low leakage inductance, wherein the phase branch has two parallel DC connections. Summary of the invention

[0007] The object of the present invention is to provide an improved power module and a corresponding electrical device which in particular allow a low-inductance connection technique.

[0008] This object is achieved with a power module of the type mentioned at the outset in that the respective remaining DC connections are arranged between the AC connection side and the DC connection side and in plan view in the region of the printed circuit board, in particular in the region of the transistor modules of the power module.

[0009] The object is achieved, among other things, by an electrical device of the type mentioned in the introduction in that the electrical device has at least one power module proposed in this way.

[0010] Furthermore, the object is achieved by a method for producing the proposed power module by means of the following method steps:

[0011] -Providing an initial power module having:

[0012] o at least one AC connection arranged on the AC connection side,

[0013] o two DC connections arranged on the DC connection side,

[0014] - providing a printed circuit board between the AC connection side and the DC connection side, so that one of the intermediate DC connections and one of the external DC connections are each arranged on the DC connection side and outside the printed circuit board in plan view, and

[0015] At least one further DC connection is provided between the AC connection side and the DC connection side and in plan view in the region of the printed circuit board, in particular in the region of a transistor module of the power module.

[0016] The proposed power module has a printed circuit board, which is preferably electrically connected to each DC connection and to each AC connection. In particular, the proposed power module can be supplied with an AC voltage on one side, namely the AC connection side, and a DC voltage on the opposite side, namely the DC connection side. For example, the printed circuit board can convert an AC voltage supplied to the power module via an AC connection or multiple AC connections into a corresponding DC voltage, which the power module can provide via the DC connection. Conversely, the printed circuit board can, for example, convert a DC voltage that can be supplied to the power module via a DC connection into a corresponding AC voltage, which the power module can provide via an AC connection or an AC connection. For the voltage conversion mentioned, the power module can, for example, have at least one semiconductor component or power semiconductor, that is, in particular, such a component, which is based on silicon, gallium nitride or silicon carbide and is designed in a power electronic device for controlling and switching high currents and voltages, that is, in particular currents greater than 1 ampere and voltages greater than about 24 volts. Examples of such components are power diodes, thyristors, triacs and transistors, such as power MOSFETs, IGBTs, etc. In addition, the power module can have a resistor, such as a measuring resistor. Preferably, the power module has a transistor, preferably at least two transistors, wherein at least one of the transistors can be arranged between two DC connections. In this case, the transistor or transistors can be part of a transistor module of the power module.

[0017] At least one AC connection is arranged on the AC connection side of the power module, wherein there are usually two such AC connections, which are usually supplied with the same AC voltage. Two DC connections, namely one external DC connection in the external DC connection and one intermediate DC connection or one intermediate DC connection in the intermediate DC connection, are arranged on the DC connection side of the power module. The remaining DC connection or the remaining multiple DC connections are arranged between the AC connection side and the DC connection side, wherein the remaining DC connection or the remaining multiple DC connections are also arranged in the area of ​​the printed circuit board in the plan view. Therefore, in the plan view, the printed circuit board is at least partially covered by the remaining DC connection or the remaining DC connection. For example, when a corresponding AC connection or two DC connections arranged on the DC connection side can be basically arranged in the plane of the printed circuit board and are arranged in the extension of the printed circuit board facing the AC connection side or the DC connection side, the corresponding remaining DC connections are arranged above the printed circuit board.

[0018] The power module may have, for example, one or more transistor modules, in particular IGBT modules, wherein the corresponding transistor module includes a transistor and may have other elements, such as electrical connections, a transistor module housing or a transistor module cooling body, if necessary. When a remaining DC connection or a plurality of remaining DC connections are arranged on the front side of a printed circuit board, the corresponding transistor module can be arranged on the printed circuit board, for example, on the back side of the printed circuit board. Preferably, the corresponding remaining DC connection is arranged in the area of ​​the corresponding transistor module in a plan view. Therefore, in a plan view, the corresponding remaining DC connection can be arranged first, then the printed circuit board and then the corresponding transistor module. Preferably, the corresponding transistor module is electrically connected to the printed circuit board and to the corresponding remaining DC connection. A particularly low-inductance structure can be achieved by this design of the power module.

[0019] For example, the proposed power module can be designed to be in the shape of a cube, wherein the AC connection side and the DC connection side are opposite to each other (for example, as the upper and lower sides of a cuboid). The remaining DC connection or the remaining multiple DC connections can then be arranged, for example, on one side of the cuboid. In some examples, the power module can be roughly in the form of a domino game, which is relatively thin and long and has a relatively large base surface. In this example, the AC connection side and the DC connection side can be arranged, for example, on the two smallest sides. The remaining DC connection or the remaining multiple DC connections can then be arranged, for example, on two medium-sized sides. For example, a power module shaped in this way is placed on its base surface (i.e., one of its two largest sides) on a cooling body.

[0020] In addition, the proposed power module can, for example, have exactly three DC connections, namely a positive DC connection, an intermediate DC connection and a negative DC connection. In this example, the positive DC connection and the intermediate DC connection are arranged on the DC connection side, and the negative DC connection is arranged between the AC connection side and the DC connection side and is arranged in the area of ​​the printed circuit board or the corresponding transistor module in a plan view. Optionally, the negative DC connection and the intermediate DC connection are arranged on the DC connection side, and the positive DC connection is arranged between the AC connection side and the DC connection side and is arranged in the area of ​​the printed circuit board or the corresponding transistor module in a plan view, so that the negative DC connection and the positive DC connection are exchanged. If the proposed power module has exactly three DC connections, a 3-level application is achieved, which has three different DC potentials.

[0021] Furthermore, the proposed power module may also have four or more DC connections, namely a positive DC connection, two or more intermediate DC connections and a negative DC connection. In this example, the positive DC connection and one of the intermediate DC connections are arranged on the DC connection side. The negative DC connection and the remaining intermediate DC connection or the remaining intermediate DC connections are arranged between the AC connection side and the DC connection side and in the area of ​​the printed circuit board or the corresponding transistor module in a plan view. If the proposed power module has exactly four or more DC connections, applications with 4 or more levels or DC potentials can be realized.

[0022] In the proposed power module, it is particularly advantageous that a low-inductance structure can be achieved. This is achieved in particular by arranging the two external DC connections relatively close to one another. For example, when the power module is used in a 3-level converter as an intermediate circuit connection DCP-DCM-DCN, the DC connections DGB, DCM, DCN are arranged close to one another, which, for example, helps to significantly improve the switching characteristics of the power switches present in the converter or power module and thus significantly reduce the power loss of the power semiconductors.

[0023] Furthermore, the power module can have a housing which at least partially surrounds the printed circuit board and any further components of the power module.

[0024] The DC connection and the AC connection can each be designed, for example, as a screw connection.

[0025] In an advantageous embodiment of the invention, the respective intermediate DC connection is arranged between the positive DC connection and the negative DC connection.

[0026] Particularly good results with regard to the low-inductance structure can be achieved by arranging the corresponding central DC connection between two outer DC connections, for example in a clockwise or counterclockwise plan view of the power module, first the negative DC connection, then the central DC connection or the central DC connection and finally the positive DC connection.

[0027] If more than one intermediate DC connection is present, the intermediate DC connections are preferably arranged such that, depending on their respective set potential, they increase from the negative DC connection to the positive DC connection or decrease from the positive DC connection to the negative DC connection.

[0028] For example, the DC connections are arranged substantially equidistant from one another. In a power module having three DC connections, the middle DC connection is therefore substantially at the same distance from the negative DC connection. This means that the middle DC connection is arranged substantially in the middle between the positive DC connection and the negative DC connection. Deviations from equidistant distances of, for example, ±20% or ±10% are still acceptable.

[0029] Particularly advantageous is a design of the power module in which two external DC connections are arranged relatively close to one another, wherein an intermediate DC connection or multiple intermediate DC connections are arranged in between. This makes it possible to further improve the switching characteristics of power switches that may be present in the converter or power module and thus further reduce the power loss of the power semiconductors.

[0030] In a further advantageous embodiment of the invention, the printed circuit board has at least one connection pin extending from the printed circuit board between the AC connection side and the DC connection side, wherein the respective remaining DC connections of the DC connections are electrically connected to the respective connection pin.

[0031] For example, the corresponding connecting pins extend vertically from the plane of the flat printed circuit board and are arranged between the AC connector side and the DC connector side. Therefore, the corresponding remaining DC connectors in the DC connector are electrically connected to the corresponding connecting pins, and the corresponding remaining DC connectors in the DC connector can be arranged in the area of ​​the printed circuit board or the corresponding transistor module in a plan view. In some examples, two or more connecting pins can also be provided for each corresponding remaining DC connector, thereby achieving a larger current. In addition, two or more DC connectors in the remaining DC connectors can be provided, and the DC connectors are connected to the printed circuit board through one or more corresponding connecting pins. The above-mentioned applications with 4 or more levels or DC potentials can be realized by this design of the power module.

[0032] For example, the corresponding connecting pins can be connecting pins of a transistor or of the above-mentioned transistor module, which is arranged on the printed circuit board or on the rear side of the printed circuit board.

[0033] In a further advantageous embodiment of the invention, the power module also comprises a corresponding conductor surface, wherein the corresponding conductor surface is arranged between the corresponding connection pin and the corresponding remaining DC connection of the DC connection, and wherein the corresponding connection pin and the corresponding remaining DC connection of the DC connection are electrically connected to the corresponding conductor surface.

[0034] The respective conductor surface can be designed, for example, as a plate of an electrically conductive material, such as copper or aluminum, or can also be designed as a DGB (direct copper bond) and can be electrically connected to the respective connection pin and to the respective remaining DC connection of the DC connection. The electrical connection of the respective connection pin to the respective remaining DC connection of the DC connection is facilitated by the respective conductor surface and is also mechanically more robust. In the case of two or more remaining DC connections, at least one conductor surface is provided for each remaining DC connection.

[0035] For example, the corresponding conductor surface can be fastened, in addition to being fixed by corresponding connecting pins, to the printed circuit board and / or to a housing of the power module that may be present.

[0036] In a further advantageous embodiment of the invention, the respective conductor surface is arranged parallel to the printed circuit board, wherein, alternatively or additionally, the printed circuit board completely covers the respective conductor surface in plan view.

[0037] The arrangement of the corresponding conductor surfaces parallel to the printed circuit board results in a compact and stable structure which also supports low-inductance connection technology. The compact structure also supports that the printed circuit board completely covers the corresponding conductor surfaces, wherein preferably the corresponding connection pins are covered by the corresponding conductor surfaces in a plan view of the printed circuit board.

[0038] In a further advantageous embodiment of the invention, the power module further comprises at least two capacitors, wherein one of the capacitors is electrically connected to one of the external DC connections and to one of the intermediate DC connections, and wherein another of the capacitors is electrically connected to another of the external DC connections and to one of the intermediate DC connections, and wherein the electrical connection between the respective capacitor and the respective DC connection is at most twice as long as the distance between the two external DC connections, in particular at most exactly the same length or at most half as long.

[0039] In the proposed design of a power module with three DC connections, i.e., adapted for 3-level applications, at least two capacitors are provided, wherein one capacitor is electrically connected to the positive DC connection and the middle DC connection and the other capacitor is electrically connected to the middle DC connection and the negative DC connection. Correspondingly, in the proposed design of a power module with four or more DC connections, i.e., adapted for applications or DC potentials with 4 or more levels, at least three or correspondingly more capacitors are provided, wherein one capacitor is electrically connected to the positive DC connection and the middle DC connection of the second highest potential, wherein the next capacitor is electrically connected to the middle DC connection of the second highest potential and the third highest potential, and so on, until the last capacitor is electrically connected to the middle DC connection of the second lowest potential and the negative DC connection. In principle, two or more capacitors can also be arranged in series or in parallel between the DC connection pairs.

[0040] Here, a particularly low-inductance structure can be achieved in that the electrical connection between the respective capacitor and the respective DC connection is designed to be as short as possible, advantageously at most twice as long, in particular at most as long or at most half as long, as the distance between the two external DC connections. In some examples, the connection can also be at most twice as long, in particular at most as long or at most half as long, as the distance between the DC connections of the respective pair of DC connections.

[0041] In a further advantageous embodiment of the invention, the power module also comprises a capacitor plate on which corresponding capacitors are arranged, wherein the capacitor plate is preferably arranged parallel to the printed circuit board and wherein the corresponding capacitors are arranged on the capacitor plate in particular within a rectangle which is defined in plan view by the DC connection and is oriented parallel to the printed circuit board.

[0042] For example, the capacitor plate can be designed as another printed circuit board. A capacitor is arranged on the capacitor plate, wherein the capacitor is electrically connected to the DC connection as described above. The simple and equally solid structure of the power module can be realized in particular by the following manner, that is, the capacitor plate is arranged parallel to the printed circuit board and the capacitor plate is located on the upper side of the printed circuit board, for example. In addition, the compact and particularly low-inductance structure of the power module can be realized in the following manner, that is, the capacitor plate is arranged in the region of the DC connection or the corresponding transistor module, so that the corresponding capacitor is also arranged near the DC connection or arranged in the region of the DC connection. Usually, the DC connection is arranged here so that the DC connection defines a rectangle in the plan view of the printed circuit board or can be surrounded by a rectangle, wherein, preferably, the smallest possible such rectangle is observed. Preferably, the corresponding capacitor on the capacitor plate is arranged in the rectangle, thereby being able to realize a short electrical connection path between the corresponding DC connection and the corresponding capacitor and therefore the overall low-inductance structure of the power module.

[0043] In some examples, the electrical connection between the respective capacitor and the respective DC connection is at most twice as long as the distance between the two external DC connections, in particular at most exactly as long or at most half as long.

[0044] In particular, at least half of the capacitors of the power module, preferably three quarters or all of the capacitors of the power module are arranged in the rectangle or are electrically connected to the corresponding DC connection via an electrical connection.

[0045] The capacitor plate can be fastened, for example, to a printed circuit board and / or to a possibly present housing of the power module.

[0046] In a further advantageous embodiment of the invention, the power module further comprises a corresponding busbar which is electrically connected to the corresponding DC connection and optionally to the corresponding capacitor, wherein the busbars are arranged at least predominantly parallel to one another and wherein the corresponding busbar of the corresponding intermediate DC connection is arranged between the busbars of the two outer DC connections.

[0047] Each DC connection can therefore be provided with a busbar, wherein the busbars are guided parallel to one another at least over half their length. Preferably, the busbars are guided parallel to one another to a large extent, for example at least over three quarters or 90% of their length. In particular, the busbars can be arranged equidistantly from one another, that is, in a power module with three busbars, the busbar with intermediate potential is arranged in the middle between the busbar with negative potential and the busbar with positive potential, wherein deviations from ±5% to ±10% can also be acceptable, and wherein the equidistant arrangement of the busbars can be arranged, for example, on the above-mentioned length, i.e. on at least 50%, 75% or 90% of the length of the busbar. If there are more than one intermediate DC connection, two adjacent busbars thus preferably have the same mutual distance, wherein the equidistance also has this deviation or can exist on this length. In this case, the parallel or equidistant guidance of the busbars contributes to the low-inductance structure of the power module.

[0048] Furthermore, a low-inductance structure of the power module is supported by arranging the busbar of a central DC connection or the busbars of a plurality of central DC connections between the busbars of two external DC connections. If more than one central DC connection is present, the busbars of the central DC connections are preferably arranged increasing from the negative DC connection to the positive DC connection or decreasing from the positive DC connection to the negative DC connection, depending on their respective set potential.

[0049] Furthermore, the respective busbar can have a rectangular cross section, wherein the long sides or short sides of the rectangle are preferably oriented substantially perpendicularly to the plane of the printed circuit board. This enables a compact design of the power module.

[0050] In a further advantageous embodiment of the invention, the power module further comprises at least one buffer capacitor, wherein the respective buffer capacitor is arranged on a printed circuit board, wherein the respective buffer capacitor is electrically connected to the respective DC connection, and wherein the electrical connection between the respective buffer capacitor and the respective DC connection is at most twice as long as the distance between two external DC connections, in particular at most exactly the same length or at most half as long.

[0051] The corresponding buffer capacitors also contribute to the low-inductance structure of the power module, for which purpose the corresponding buffer capacitors are arranged in close proximity to the corresponding DC connection and are electrically connected to the DC connection. Furthermore, the corresponding buffer capacitors are electrically connected to a suitable potential.

[0052] In another advantageous design of the present invention, the power module can operate with an electrical power of at least tens of kW, preferably 40kW to 500kW, an AC voltage of at least hundreds of V, preferably 280V to 800V, a DC voltage of at least hundreds of V, preferably 800V to 1500V, and / or a current of tens of A, preferably 70A to 1000A.

[0053] In another advantageous embodiment of the present invention, the power module has a width of 80 cm 2 Up to 100cm 2 A base area, wherein the base area is in particular rectangular with a side length of approximately 150 mm at the long sides of the base area and a side length of approximately 62.5 mm at the short sides of the base area.

[0054] In another advantageous embodiment of the present invention, the electrical device has a substrate and at least two of the proposed power modules, wherein the power modules are arranged side by side on the substrate so that the DC connection sides of the power modules point in the same direction, and also has corresponding device busbars, which are electrically connected to the corresponding DC connections (DCP, DCM, DCN) of the corresponding power modules and optionally to the corresponding capacitors, and wherein the device busbars are arranged at least partially parallel to each other.

[0055] For example, the corresponding device busbars can be designed integrally with the respective corresponding busbars of the individual power modules. The DC connections of the power modules with the same potential can thus be connected to the corresponding device busbars, wherein the respective corresponding busbars of the individual power modules can be part of the corresponding device busbars. By arranging the power modules so that the respective DC connection sides of the power modules face the same direction, relatively short respective device busbars can be achieved, which contributes to a low-inductance structure of the electrical device. This arrangement is achieved, for example, by arranging the power modules side by side in a row.

[0056] As has already been described above for the corresponding power modules with respect to the corresponding busbars, the corresponding device busbars can also be guided parallel or equidistantly to one another over at least half their length, wherein the above-mentioned deviations can still be acceptable with respect to the device busbars. The parallel or equidistant guidance of the device busbars here again contributes to the low-inductance structure of the electrical device. Preferably, the device busbars are also arranged so that their potential rises from the negative DC connection to the positive DC connection or drops from the positive DC connection to the negative DC connection.

[0057] The electrical device preferably has at least three such power modules, wherein a three-phase alternating current can be supplied to the electrical device and the respective power module receives one of the three phases of the alternating current.

[0058] It is particularly advantageous in the proposed method that, for example, a conventional power module which is available at a favorable cost and is designed in particular for Class 2 applications can be used as a starting power module. Such a conventional power module can, for example, have only at least one AC connection on the AC connection side and two DC connections on the DC connection side. Such a conventional power module is known, for example, from the above-mentioned US Pat. No. 8,847,328 B1, which has four power connections, namely two AC connections and two DC connections arranged opposite these AC connections. Such a conventional power module can also be used as a starting power module for the proposed method without its own printed circuit board. In particular, the starting power module can have a housing and, for example, existing (threaded) connections of a conventional power module.

[0059] This initial power module is then equipped with a printed circuit board suitable for the proposed power module, wherein the printed circuit board is arranged in such a way that one of the intermediate DC connections and one of the external DC connections are each arranged on the DC connection side and outside the printed circuit board in plan view. In addition, the initial power module is equipped with at least one further DC connection, which is each arranged between the AC connection side and the DC connection side and is arranged in plan view in the region of the printed circuit board or the corresponding transistor module.

[0060] Preferably, a corresponding electrical connection of the corresponding AC connection and the corresponding DC connection to the printed circuit board is also established.

[0061] As already mentioned above, the initial power module can in particular have a housing and existing (threaded) connections, for example of a conventional power module, wherein a printed circuit board and an additional DC connection or an additional DC connection are then provided and mounted within the scope of the proposed method, and wherein, for example, the arrangement of transistors or IGBTs is additionally changed or re-provided.

[0062] It is particularly advantageous in the proposed power module or electrical device and in particular in the proposed method that, for example, a low-inductive structure can be realized based on conventional power modules or IGBT modules with screw connections without extensive adaptation of the module housing of conventional power modules. In particular, a special arrangement of the connection technology for 3-level applications is proposed, which allows a low-inductive structure in an existing conventional module housing. For example, an existing 2-level IGBT module housing with solder-in pins or press-in pins arranged only in a different manner can be used as the basis for a 3-level application or a 3-level power module.

[0063] For example, the power screw terminal is led out unchanged, but connected differently inside. Therefore, pins 10 and 11 can also be led out as AC terminals, wherein pin 4 can be used as a positive DC terminal, pin 3 can be used as an intermediate DC terminal and the negative DC terminal can be led out through a lateral welded pin or pressed pin. Through these lateral pins connected to the printed circuit board, the current can be tapped through the (e.g. soldered or pressed) screw terminals installed on the printed circuit board. In addition, the positive DC terminal and the negative DC terminal can be selectively exchanged. For the structure of the power module with the lowest possible inductance, the intermediate DC terminal is preferably arranged in the middle. Therefore, a complete low-inductance 3-level power module is produced by connecting the initial power module, the printed circuit board and the external screw terminal, which can be used with minimal cost investment. Different busbar variants can be used, with the high side arranged vertically or flatly stacked. For applications with more than three DC potentials, corresponding power modules or corresponding manufacturing methods are proposed.

[0064] This proposed, special compact combination has decisive advantages over conventional connection technologies in power modules, especially IGBT modules: for example, the application is optimally suitable for 3-level applications, but also for applications with 4 or more levels or DC potential. Here, low-inductance connection technology is implemented in particular at the power module. In addition, the proposed power module or method reuses the existing IGBT module housing or the original power module. A compact connection technology is proposed here, which does not exceed the IGBT module housing or requires more structural space than the IGBT module housing or the original power module. The proposed method is particularly suitable for small numbers of pieces, because there is no need to invest in a new 3-level housing. This also applies to universal housings with optionally plug-in solder-in pins or press-in pins. In addition, other structural elements, such as buffers, can be arranged close to the IGBT connection or the DC connection. Here, compared with optional solutions, the proposed power module is very compact and, for example, only occupies 93.8 cm 2 This relatively small footprint can be crucial for use in compact frequency converters. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The present invention is described and explained in more detail below with the aid of the embodiments shown in the accompanying drawings.

[0066] Figures 1 to 8 The first to eighth embodiments of the proposed power module are shown,

[0067] Fig. 9 An embodiment of the proposed electrical device is shown, and

[0068] Fig.10 A flow chart showing an embodiment of the proposed method for manufacturing an embodiment of a power module is shown. DETAILED DESCRIPTION

[0069] Figure 1 A first embodiment of the proposed power module 1 is shown, wherein a schematic diagram is presented.

[0070] The power module 1 has an AC connection side 2 and a DC connection side 3 opposite to the AC connection side 2, and a printed circuit board 4. In addition, the power module has two AC connections AC arranged on the AC connection side 2 and three DC connections DCP, DCM, DCN. The middle DC connection DCM and the positive DC connection DCP of the three DC connection sides are arranged on the DC connection side 3 and arranged outside the printed circuit board 4 in a plan view. The third DC connection of the three DC connections DCP, DCM, DCN is a negative DC connection DCN, which is arranged between the AC connection side 2 and the DC connection side 3 and arranged in the area of ​​the printed circuit board 4 in a plan view. Here, the positive DC connection DCP and the negative DC connection DCN form two external DC connections DCP, DCN.

[0071] The two AC connections AC and the two DC connections arranged on the DC connection side, namely the central DC connection DCM and the positive DC connection DCP, are arranged essentially in the plane of the printed circuit board 4 and in the extension of the printed circuit board 4 towards the AC connection side 2 or the DC connection side 3. In contrast, the negative DC connection DCN is arranged on the printed circuit board 4 and between the AC connection side 2 and the DC connection side 3.

[0072] Furthermore, the power module has a housing 16 which at least partially surrounds the printed circuit board 4 .

[0073] Preferably, as in Figure 1 As shown in , the intermediate DC connection DCM is arranged between the positive DC connection DCP and the negative DC connection DCN. For example, the DC connections DCP, DCM, DCN are each arranged substantially equidistant from one another.

[0074] exist Figure 1 The power module 1 shown in FIG. 1 has here exactly three DC connections DCP, DCM, DCN, so that a 3-class application is thereby possible.

[0075] Figure 2 A second embodiment of the proposed power module 1 is shown, in which a schematic diagram is again presented. Figure 1 Like reference numerals in the drawings represent like objects. Since the second embodiment has some similarities with the first embodiment, some differences will be explained below.

[0076] The power module further comprises a transistor module 20 which is arranged behind the printed circuit board 4 in a plan view of the printed circuit board 4. Thus, in a plan view of the power module 1, the DC connection DCN is arranged first, then the printed circuit board 4 and then the transistor module 20. The DC connection DCN is arranged between the AC connection side 2 and the DC connection side 3 and in a plan view in the region of the transistor module 20 of the power module 1.

[0077] Such a corresponding transistor module 20 can, for example, also be provided in the other exemplary embodiments of the proposed power module 1, wherein the corresponding remaining DC connection is then arranged between the AC connection side 2 and the DC connection side 3 and in the region of the (corresponding) transistor module 20 of the power module 1 in a plan view.

[0078] Figure 3 A third embodiment of the proposed power module 1 is shown, wherein again a plan view is presented. As the third embodiment has some similarities with the first embodiment, some differences will be explained below.

[0079] Figure 3 The power module 1 shown in has four DC connections DCP, DCMP, DCMN, DCN, namely the positive DC connection DCP, but now has two intermediate DC connections DCMP and DCMN and a negative DC connection DCN. Preferably, the four DC connections DCP, DCMP, DCMN, DCN are designed for respective potentials that are substantially equidistant from one another, so that the potential differences between the DC connection pairs DCP-DCMP, DCMP-DCMN and DCMN-DCN are substantially the same. As shown in Figure 3 As shown in FIG. 1 , in the power module 1 , a positive DC connection and an intermediate DC connection DCMP are arranged on the DC connection side 3. The negative DC connection DCN and the intermediate DC connection DCMN are arranged between the AC connection side 2 and the DC connection side 3 and in the area of ​​the printed circuit board 4 in a plan view. A 4-level application can be realized using four DC connections DCP, DCMP, DCMN, DCN.

[0080] Preferably, as in Figure 3 As shown in , two intermediate DC connections DCMP and DCMN are arranged between the positive DC connection DCP and the negative DC connection DCN. Here, the four DC connections DCP, DCMP, DCMN, DCN are arranged descending from the positive DC connection DCP to the negative DC connection DCM according to their respective set potentials. For example, the DC connections DCP, DCMP, DCMN, DCN are arranged substantially equidistant from one another.

[0081] Figure 4A fourth embodiment of the proposed power module 1 is shown, wherein again a plan view is presented. As the fourth embodiment has some similarities with the first embodiment, some differences will be explained below.

[0082] The printed circuit board 4 has a plurality of connection pins 5 extending from the printed circuit board 4 between the AC connection side 2 and the DC connection side 3. The connection pins can be, for example, connection pins of a transistor or transistor module 20 (not shown in detail), which can be arranged on the printed circuit board 4 or on the rear side of the printed circuit board 4. In this case, the negative DC connection DCN is electrically connected to the connection pin 5 via a connection 17 and a conductor surface 6. The conductor surface 6 can be designed, for example, as a DCB and can be arranged in particular parallel to the printed circuit board 4. Preferably, the printed circuit board 4 is arranged in a plan view, that is to say, for example, Figure 4 As shown in FIG. 1 , the conductor surface 6 is completely covered.

[0083] Figure 5 A fifth embodiment of the proposed power module 1 is shown, wherein a perspective and schematic view of the power module 1 is presented. As the fifth embodiment has some similarities with the fourth embodiment, some differences will be explained below.

[0084] The power module 1 further comprises three busbars 9N, 9M and 9P, which are electrically connected to corresponding DC connectors DCP, DCM and DCN. Figure 5 As shown in FIG. 4 , the three busbars 9N, 9M, and 9P are arranged substantially parallel to each other and equidistantly. Here, the busbar 9M of the intermediate potential is arranged between the busbars 9P and 9N of the positive potential and the negative potential. In addition, the three busbars 9N, 9M, and 9P each have a rectangular cross-section, wherein the long side of the corresponding rectangle is perpendicular to the plane of the printed circuit board 4.

[0085] Figure 6 A sixth embodiment of the proposed power module 1 is shown, wherein again a perspective and schematic view of the power module 1 is presented. As the sixth embodiment has some similarities with the fifth embodiment, some differences will be explained below.

[0086] The power module 1 further comprises a plurality of buffer capacitors 10, which are arranged on the printed circuit board 4 and are electrically connected to the corresponding DC connections DCP, DCM, DCN in a matching manner. Preferably, the electrical connection between the corresponding buffer capacitor 10 and the corresponding DC connection DCP, DCM, DCN is at most twice as long as the distance between the two external DC connections DCP, DCN, in particular at most exactly the same length or at most half the length.

[0087] Figure 7A seventh embodiment of the proposed power module 1 is shown, wherein a perspective and schematic view of the power module 1 is presented. Since the seventh embodiment also has some similarities with the fifth embodiment, some differences will be explained below.

[0088] The three busbars 9N, 9M and 9P again have a rectangular cross section, wherein now, however, the short sides of the respective rectangle are perpendicular to the plane of the printed circuit board 4. The flat busbars 9N, 9M and 9P are therefore arranged parallel to the plane of the printed circuit board 4.

[0089] Figure 8 An eighth embodiment of the proposed power module 1 is shown, wherein again a schematic diagram is presented. Since the eighth embodiment also has some similarities with the first embodiment, some differences are explained below.

[0090] The power module 1 has two capacitors 7, of which one capacitor 7 is electrically connected to the positive DC connection DCP and the intermediate DC connection DCM via an electrical connection 8, and of which the other capacitor 7 is electrically connected to the intermediate DC connection DCM and the negative DC connection DCN via another electrical connection 8. In this case, the respective electrical connection 8 between the respective capacitor 7 and the respective DC connection DCP, DCM, DCN is at most twice as long as the distance between the two outer DC connections DCP, DCN, in particular at most exactly the same length or at most half as long.

[0091] The power module 1 further comprises a capacitor plate 11 on which the capacitor 7 is arranged. The capacitor plate 11 is preferably arranged parallel to the printed circuit board 4, wherein the capacitor 7 is arranged on the capacitor plate 11, in particular in a rectangle which is bounded in plan view by the DC terminals DCN, DCM, DCP and which is oriented parallel to the printed circuit board 4.

[0092] Fig. 9 An embodiment of a proposed electrical device 12 is shown, in which a schematic diagram is presented.

[0093] The electrical device 12 has a substrate 13 on which three power modules 1 are arranged, wherein the three power modules 1 can be designed in particular according to one of the above-described exemplary embodiments. The three power modules 1 are arranged side by side and are oriented so that their respective DC connection sides 3 point in the same direction. Fig. 9 The electrical device 12 further has three device buses 14P, 14M and 14N, which are electrically connected to the corresponding DC connectors DCP, DCM and DCN of the corresponding power module 1. For example, the corresponding power module 1 may have three buses 9P, 9M and 9N, as described in embodiments 4 and 5, wherein the buses 9P, 9M and 9N of the corresponding power module 1 may be designed integrally with the three device buses 14P, 14M and 14N, as described in embodiments 4 and 5. Fig. 9 as shown in .

[0094] In addition, as in Fig. 9 As indicated in , the three device buses 14P, 14M and 14N are arranged substantially parallel to each other and equidistant from each other. Here, the device bus 14M of the intermediate potential is arranged between the device buses 14P and 14N of the positive potential and the negative potential. Here, the three device buses 14P, 14M and 14N can each have a rectangular cross section, wherein the long side or the short side of the corresponding rectangle is perpendicular to the plane of the printed circuit board 4.

[0095] Fig.10 A flow chart of an exemplary embodiment of a proposed method 100 for producing an exemplary embodiment of a power module 1 is shown.

[0096] In a first step 102, an initial power module 15 is provided, which has two AC connections AC arranged on the AC connection side 2 and two DC connections DCP, DCN arranged on the DC connection side 3. The initial power module 15 also has a housing 16, which holds the AC connections AC and the DC connections DCP, DCN. As already mentioned above, such an initial power module 15 can be, for example, a conventional power module known, for example, from the already mentioned US Pat. No. 8,847,328 B1.

[0097] In a second step 104, a suitable printed circuit board 4 is provided and arranged between the AC connection side 2 and the DC connection side 3. In this case, the intermediate DC connection DCM and the positive DC connection DCP are arranged on the DC connection side 3 and in plan view outside the printed circuit board 4. In particular, the negative DC connection DCN of the original power module 15 is reused here as the intermediate DC connection DCM of the proposed power module 1.

[0098] In a third step 106 , a negative DC connection DCN is provided between the AC connection side 2 and the DC connection side 3 and in plan view in the region of the printed circuit board 4 .

[0099] Preferably, for example, a corresponding electrical connection of the AC connection AC and the corresponding DC connections DCP, DCM, DCN to the printed circuit board 4 is also established in a further step.

Claims

1. A power module (1) comprising an AC connection side (2) and a DC connection side (3) opposite to the AC connection side (2), wherein: The power module (1) further comprises: - a printed circuit board (4), - at least one AC connection (AC) arranged on the AC connection side (2), and - at least three DC connections (DCP, DCM, DCN), the DC connections comprising one or more intermediate DC connections (DCM) and two external DC connections (DCP, DCN), the external DC connections comprising a positive DC connection (DCP) and a negative DC connection (DCN), wherein one of the intermediate DC connections (DCM) and one of the external DC connections (DCP, DCN) are each arranged on the DC connection side (3) and outside the printed circuit board (4) in plan view, and It is characterized in that The corresponding remaining DC connections (DCP, DCM, DCN) of the DC connection are arranged between the AC connection side (2) and the DC connection side (3) and in plan view in the region of the printed circuit board (4), in particular in the region of a transistor module (20) of the power module (1).

2. The power module (1) according to claim 1, in, The respective intermediate DC connection (DCM) is arranged between the positive DC connection (DCP) and the negative DC connection (DCN).

3. The power module (1) according to any one of the preceding claims, in, The printed circuit board (4) has at least one connecting pin (5) extending from the printed circuit board (4) between the AC connector side (2) and the DC connector side (3), and Wherein, the corresponding remaining DC connectors in the DC connectors (DCP, DCM, DCN) are electrically connected to the corresponding connecting pins (5).

4. The power module (1) according to claim 3, The power module also has a corresponding conductor surface (6), wherein: The corresponding conductor surface (6) is arranged between the corresponding connection pin (5) and the corresponding remaining DC connection of the DC connection (DCP, DCM, DCN), and the corresponding connection pin (5) and the corresponding remaining DC connection of the DC connection (DCP, DCM, DCN) are electrically connected to the corresponding conductor surface (6).

5. The power module according to claim 4, in, The respective conductor surface (6) is arranged parallel to the printed circuit board (4), and / or The printed circuit board (4) completely covers the corresponding conductor surface (6) in a plan view.

6. The power module (1) according to any one of the preceding claims, The power module also has at least two capacitors (7), wherein: One of the capacitors (7) is electrically connected to one of the external DC connections (DCP, DCN) and one of the intermediate DC connections (DCM), and another of the capacitors (7) is electrically connected to another of the external DC connections (DCP, DCN) and one of the intermediate DC connections (DCM), and Therein, the electrical connection (8) between the respective capacitor (7) and the respective DC connection (DCP, DCM, DCN) is at most twice as long as the distance between the two external DC connections (DCP, DCN), in particular at most exactly the same length or at most half as long.

7. The power module (1) according to any one of the preceding claims, The power module also has a corresponding busbar (9), which is electrically connected to the corresponding DC connection (DCP, DCM, DCN) and optionally to the corresponding capacitor (7). in, The busbars (9) are arranged at least predominantly parallel to one another, and In this case, the respective busbar (9) of the respective central DC connection (DCM) is arranged between the busbars (9) of the two external DC connections (DCP, DCN).

8. The power module (1) according to any one of the preceding claims, The power module also has at least one buffer capacitor (10). in, The corresponding buffer capacitor (10) is arranged on the printed circuit board (4), wherein the corresponding buffer capacitor (10) is electrically connected to the corresponding DC connector (DCP, DCM, DCN), and The electrical connection between the respective buffer capacitor (10) and the respective DC connection (DCP, DCM, DCN) is at most twice as long as the distance between the two external DC connections (DCP, DCN), in particular at most exactly the same length or at most half as long.

9. The power module (1) according to any one of the preceding claims, in, The power module (1) can be operated with an electrical power of at least several tens of kW, preferably 40 kW to 500 kW, an AC voltage of at least several hundred V, preferably 280 V to 800 V, a DC voltage of at least several hundred V, preferably 800 V to 1500 V and / or a current of several tens of A, preferably 70 A to 1000 A.

10. The power module (1) according to any one of the preceding claims, in, The power module (1) has a width of 80 cm 2 Up to 100cm 2 The base surface, In this case, the base surface is in particular rectangular and has a side length of approximately 150 mm on a long side (18) of the base surface and a side length of approximately 62.5 mm on a short side (19) of the base surface.

11. An electrical device (12), in particular a converter, comprising at least one, preferably at least three, power modules (1) according to any of the preceding claims.

12. The electric device (12) according to claim 11, The electric device comprises a substrate (13) and at least two power modules (1) according to any one of claims 1 to 10, in, The power modules (1) are arranged side by side on the substrate (13) so that the DC connection sides (3) of the power modules (1) point in the same direction. The electrical device also has a corresponding device busbar (14), which is electrically connected to the corresponding DC connection (DCP, DCM, DCN) of the corresponding power module (1) and optionally to the corresponding capacitor (7), and The device busbars (14) are arranged at least partially parallel to one another.

13. A method for producing a power module (1) according to any one of claims 1 to 10, comprising the following method steps: - providing an initial power module (15), the initial power module having: o at least one AC connection (AC) arranged on the AC connection side (2), o two DC connections (DCP, DCM, DCN) arranged on the DC connection side (3), - the printed circuit board (4) is provided between the AC connection side (2) and the DC connection side (3), so that one of the intermediate DC connections (DCM) and one of the external DC connections (DCP, DCN) are each arranged on the DC connection side (3) and outside the printed circuit board (4) in plan view, and - at least one further DC connection (DCP, DCM, DCN) is provided between the AC connection side (2) and the DC connection side (3) and in plan view in the region of the printed circuit board (4), in particular in the region of a transistor module (20) of the power module (1).

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