WO2019222784A1

WO2019222784A1 - Power module with defined recharging path and production method

Info

Publication number: WO2019222784A1
Application number: PCT/AT2019/060175
Authority: WO
Inventors: Martin NAGELMÜLLER
Original assignee: Miba Energy Holding Gmbh
Priority date: 2018-05-25
Filing date: 2019-05-24
Publication date: 2019-11-28

Abstract

The invention relates to a method for producing a power module (1), and to a power module (1), particularly for a medium-voltage or high-voltage converter (2), comprising at least one power semiconductor module (2), at least one energy storage module (5), at least one cooling device (7), and at least two busbars (10), wherein the cooling device (7) is electroconductively embodied and is connected to a protective housing (19) shielding at least the power semiconductor module (3) from the environment, said protective housing (19) comprising at least one inlet (20) for inserting and attaching a connection element (15), and an electroconductive connection element (15) is arranged in a pre-definable connection position (16) between at least the cooling device (7) and one of the busbars (10) in order to form a defined recharging path (17).

Description

Power module with defined transfer path and method of manufacture

The invention relates to a method and a power assembly for a medium or high voltage converter, in particular a modular Multilevelumrichter, wherein at least between the cooling device and a busbar a connecting element for Ausbil tion of a defined Umladepfads is arranged.

The conversion of alternating current into direct current or vice versa is carried out by using power electronic converters. Inverters (or Modular Multilevel Converter-MMC) are often used. Such modular multilevel inverters generally consist of a large number of power modules connected in series, which can also be referred to as submodules. Each power module can be switched independently of the other power modules. The arrangement of the power modules often takes place in a rack or rack, whereby small volume of construction as well as minimizing the costs and ensuring the insulation requirements of the man laugh must be observed. In this case, the Lachmann a variety of possible arrangements of energy storage modules, power semiconductor modules, so verbun dene control devices and in particular for cooling these elements provided cooling devices are known.

The busbars used for contacting the power modules are often designed as copper or aluminum conductors with a plate-shaped or rod-shaped geometry to be able to conduct the high currents loss. Due to the rapidly changing electrical potential of current-carrying busbars, it can lead to reloading of electrical charge between the busbars and other, especially flat trained, compo nents of the power assembly, which is referred to as parasitic capacitances. These parasitic capacitances may be e.g. to a housing and / or a cooling device, or between other components are formed and cause electromagnetic interference emissions, whereby the electromagnetic compatibility (EMC) is impaired taken.

The energized power assemblies usually have a variety of electronic components, which before commissioning on their Lunktionstüchtigkeit and Intactness of the insulation must be tested. This can be done by separately testing the individual components, such as the individual power semiconductors, before assembling the power assembly. However, this entails the risk that damage to individual components occurs during assembly or that electrically conductive small parts in the power module unintentionally remain, which can lead to an undefined Stromentladepfad or unwanted partial discharge during operation. In the worst case, this can lead to a short circuit. Testing or testing of the entire power subassembly in the final state at the end of the mechanical completion is usually only possible with very high manual effort. This represents a significant disadvantage for the cost-effective production and quality assurance.

The object of the present invention was to overcomes the disadvantages of the prior art and to provide an apparatus and a method by means of which a simple, safe and cost-effective design of a defined current discharge path can be carried out. A further object is to entzu unavoidable parasitic discharge currents or leakage currents of unwanted locations of the power assembly and thus reduce EMC problems, as well as defects and / or current-induced Materialdegradatio NEN. Moreover, the invention has for its object a simple procedural ren to avoid the above problems and to test a power assembly, such as the increase in safety and quality, and further the reduction of manufacturing or testing costs to provide.

This object is achieved by a device, hereinafter power module, and a United drive according to the claims.

The power module according to the invention for a medium or high voltage converter, in particular a modular multilevel converter, comprises at least one power semiconductor module, at least one energy storage module, at least one cooling device and at least two busbars. The cooling device is electrically conductive and connected to a, at least the power semiconductor module from the environment from shielding, protective housing, which ren at least one insertion opening for Einfüh and attaching a connecting element. At a predetermined connection position is an electrically conductive connection element, to form a defined Umladepfads, arranged between at least the cooling device and one of the busbars. Such Umladepfad can also be understood as a defined current return path or discharge path ver.

For contacting the power module, in particular the power semiconductor or the power semiconductor module, busbars are provided. Current connections of the busbars can be used to contact and conduct the current into the power module and / or to adjacent series-connected power modules and protrude from the protective housing.

A power semiconductor group each comprises at least one power semiconductor, such as an IGBT or comparable electronic components. An energy storage module summarizes each at least one, preferably designed as a capacitor energy storage.

At least one power semiconductor module can be coupled to two electrically isolated busbars for at least one energy storage module. The Busbars provided for Beaufschla supply with different electrical potential are electrically separated from each other, preferably via at least one insulating layer, arranged separately. The busbars can be designed as part of a connection terminal for the electrical connection of the at least one energy storage module with at least one power module. The busbars may be electrically isolated from the cooling device via insulators. The exact design of the electrical components, such as e.g. The busbars, insulators, energy storage module and / or power semiconductor module can be optimized by the Lachmann accordingly the requirements of the power module.

According to the invention, the cooling device is brought to a similar or substantially the same electrical potential as the contacted bus bar by the electrical connection element, whereby the influence of parasitic capacitances can be reduced to a defined extent. Due to the design of the electrically conductive cooling device, a very good thermal conductivity and thus heat dissipation of the at least one, preferably arranged ther mixed contacting, power semiconductor module is achieved. By the formation of a defined Umladepfads between at least the, preferably metallic, cooling Device and a busbar thus unavoidable parasitic Endladeströme be kept away from un desired locations. As a result, an improved EMC emissions can be achieved. Likewise, the formation of defects and / or material aldegradation on sensitive components of the power module can be reduced or even avoided by the influence of parasitic capacities in this way.

Under certain circumstances, the power module designed according to the invention or the corresponding method can also be used for applications in the low-voltage range, or optimized by the skilled person with minor measures for such applications.

Analogous to the above-mentioned embodiment of the power module according to the invention, in the method according to the invention, at least one such power module is provided as a method step. Further method steps include,

Securing or arranging a protective housing, which terminates at least the power semiconductor module in relation to the environment, to the cooling device, which has at least one insertion opening for inserting and fastening a connecting element,

- Forming a defined Umladepfads by attaching the connecting element to a predetermined connection position between at least the cooling device and one of the busbars through the insertion opening.

By virtue of the power module designed according to the invention, in particular the protective housing connected to the cooling device, effective protection against external influences, such as dust, liquids, etc., of at least one power semiconductor group can be achieved. Conversely, the protective housing can also be used to the outside, such as in egg ner explosive destruction of a power semiconductor for shielding against umherflie ing parts and to this end formed substantially complete. The protective housing in this case comprises at least one insertion opening through which the connec tion element can be safely inserted and secured. Of great advantage here is that the connecting element is introduced as the last electrically effective element in the Leistungsbau group. Thus, contamination or damage to the power unit can be efficiently avoided. This is of particular advantage, as that any electrical tests of the insulation and / o on partial discharge stretch of individual components or even the entire Leistungsbau group can be performed before attaching the connecting element. Such tests are known to the person skilled in the art, inter alia, from the standards EN 50178, EN 60060-1 or IEC 62501 given by way of example.

Furthermore, it may be expedient if the connecting element is detachable, preferably designed as a screw, plug or latching element.

This possible embodiment allows a simple and secure installation, allows the temporary removal of the connecting element during maintenance work, or even for Prüfzwe bridges. To complete such work, the connecting element can be placed again as the last electrically effective element. In addition, a screwed, mated or latched connection element can ensure a good connection of the cooling device to the potential of the busbar. Furthermore, the connecting element is well protected against corrosion.

Furthermore, it may be provided that the connecting element has a cross section which is formed larger by more than 10%, preferably more than 20%, than a minimum cross section required for the formation of the defined transfer path and a discharge of parasitic discharge currents.

Depending on the type and size of the power assembly, parasitic Entla different currents may occur, which for the formation of the Umladepfads considered by those skilled in the design of the electrically conductive minimum cross section of the connecting element who should. However, it may be of considerable advantage, the electrically conductive cross-section of the connecting element by 10% and more, relative to the mentioned minimum cross-section increase, since in this way, in addition to the formation of a defined order charging paths, a thermally effective connection to the cooling device are formed can. Thus, in a simple manner, an additional heat dissipation be made at least from kontak ended busbar to the cooling device. In addition, at the busbar to lying support element of the connecting element, such as a screw head, a good Promote heat dissipation in the connecting element, whereby the heat dissipation can be improved.

In addition, it can be provided that at least two power semiconductor modules are arranged on at least two sides of the busbars which are normally aligned with one plane of the busbars, preferably opposite one another.

The busbars are designed as "planar", ie substantially two-dimensionally extended, electrical conductors and thus provide a reference plane in two spatial directions, wherein sides of the busbars are thus directed in the third spatial direction. The arrangement of several, ie at least two Leistungshalbleitem, on two sides of the busbars or around the busbars around can be used to homogenize the power and / or Stromvertei development is substantially in the third spatial direction. Such Anord voltage can reduce the length of the current paths and thus the undefined formation of parasitic leakage currents and thus improve the EMC. Likewise, the formation of parasitic inductances due to symmetry effects can be reduced in this way who the.

Furthermore, it can be provided that the connecting element is electrically connected to at least one of the busbars with the cooling device and that the at least one other busbar is urgently and electrically insulated therefrom.

This measure allows the skilled person a large number of possible Verbindungspositi onen, which an optimal arrangement of the respective electrical components, such as the power semiconductor modules, energy storage modules, auxiliary modules, etc., he allows, without hindering the potential connection of the cooling device to a busbar. The electrical insulation to the non-contacted bus bar can be ensured by an air gap or suitable insulating materials, such as a plastic sleeve. This can additionally increase the mechanical stability.

Also advantageous is an expression, according to which it can be provided that the connec tion element is arranged in the middle of the plane of the busbars. In this way, a particularly efficient arrangement of the at least one, preferably several, power semiconductor group (s) can take place around the busbars. This measure promotes to the symmetry of the arranged electrical components and allows the formation of approximately equal length of current paths, whereby the influence of parasitic capacitances verrin siege and the EMC can be improved. Analogously, this applies to parasitic inductances.

According to a development, it is possible that at least one of the busbars has a laterally projecting terminal lug for contacting the connecting element.

Such a projection of a busbar is inexpensive and easy to implement and also allows a particularly simple installation without additional insulation elements to provide the non-contacted busbar.

Furthermore, it may be expedient if a, preferably channel or tubular, Einführele element, at least partially formed by the insertion of the protective housing in the direction of the nearest bus bar extending.

Such an insertion element can significantly ease the insertion of the connecting element. Since this process is to be performed when the protective housing is closed, this measure also serves the loss of security of the connecting element and can shorten the neces sary assembly time and make complicated insertion or assembly tools obsolete.

In addition, it can be provided that the insertion opening by means of a Verschlussele element, preferably a plug or a screw, is closed. This Verschlussvor gear should be done during or after the attachment of the connecting element.

In this way, the protective housing can be efficiently sealed from the environment before entry or exit of liquids, dust and / or foreign bodies. Such a closure element can be understood in the context of the present invention as, the last electrically non-effective element in the manufacturing and / or maintenance process of the power assembly ver. Safety during operation, as well as during maintenance work, can hereby be significantly increased. Furthermore, it can be provided that the protective housing is electrically conductive and electrically connected to the cooling device.

The electrically conductive protective housing can thus be easily brought to the electrical potential of the cooling device and the busbar. In such an electrically conductive protective housing, the influence of parasitic capacitances and unwanted discharge currents can be very well controlled or even avoided by the electrical connection of the protective housing to the electrically conductive cooling device. Such a protective housing can also be foiled, coated and / or lacquered and yet brought by the electrical contact to the cooling device to the substantially same electrical potential, whereby unavoidable parasitic discharge currents can be directed or directed Ge.

According to a particular embodiment, it is possible that protective housing with the Kühlvor direction and one of the busbars is electrically connected.

This direct connection of the protective housing with one of the busbars and the electrically conductive cooling device can be made relatively simple by the electrical connection element. In this case, the predeterminable connection position is formed at three points along the connection element. In this way, the defined Umladepfad between at least the cooling device and one of the busbars can be selected very short. Moreover, it is easy to imagine that this measure is particularly advantageous at the end of the production and / or testing of the power assembly.

Furthermore, it can be provided that, with or after the attachment of the connecting element, the insertion opening is closed by means of a closure element, preferably a stopper or a screw.

By attaching a "closure" for the protective housing, the penetration of dirt, liquids, etc. into the interior can be efficiently prevented and thus the reliability can be increased. In addition, by closing the protective housing, the explosion protection can be increased. The insertion opening can accommodate the closure element have a suitable shape, such as a thread or the like. A separate Ver circuit element thus represents in the process according to the invention the last electrically non-effective same component in the manufacture and / or maintenance of the power assembly, whereby damage to the electrical components, for example during assembly can be very well avoided. Depending on the requirements, the closure element may also be formed, for example, as a partially insulating screw, whereby the electrical connection between tween at least the cooling device and one of the busbars can be ensured, however, the shaft and / or head of the screw is formed insulating against the protective housing. In this case, the electrical connection element and the closure element is integrally formed.

In addition, it can be provided that the insertion opening is closed by the attachment of the connecting element and the connecting position between at least the cooling device and one of the busbars and the protective housing is formed.

With this measure, a stable connection position at three points can be formed by bringing on the connecting element, whereby an additional Umladepfad is formed by the busbar to the protective housing. The closing and simultaneous electrical connection of the cooling device, a bus bar and the protective housing can increase the homogeneity with regard to the charge-reversal currents, which in turn results in improved EMC. In addition, this measure can be performed as a final process step and a relatively quick, loss-secure attachment of the connecting element ge guaranteed.

Also advantageous is an expression, according to which it can be provided that before Be fastening the protective housing, a first electrical test of the power assembly by applying a first test voltage to at least one predetermined insulation distance is performed by.

As an isolation distance can be understood in the context of the present invention, an electrical path ver, which should lie after completion of the power assembly to a common intended electrical potential. Analogously, therefore, such Isolati onsstrecke one or more electrical components or assemblies or components include. Such a first electrical test of insulation distances can be used to control egg ner base insulation, which can be detected in a very simple manner any short circuits and / or loose parts. The advantage of this measure is that such a test can be carried out relatively easily and in particular automatically before the power module is completed and the electrical connection element is introduced. Preferably, such testing is performed in the range of a few volts, such as 5 to 10 volts.

Further, it may be useful if, after the first test and / or after fastening tion of the protective housing, a second electrical test of the power assembly by applying conditions of a relative to the first test voltage increased, second test voltage is performed on at least one predetermined insulation stretch.

Such a second test can be used to test the electrical connections and Isolati onsstrecken on resilience and is usefully carried out only after the first test to avoid damage to the power module. This serves to control the functional insulation and is therefore preferably carried out in the range of 100 V to about 400 V. Advantageously, this test is performed before attaching the electrical connection element.

In addition, it can be provided that at least between one of the busbars and the cooling device and / or the protective housing, a check on the func onstüchtigkeit and / or the presence of the electrical connection element is pre-accepted.

This measure can be made as a kind of final test to check the Funktionstüch activity of the electrical connection element. In this way, the quality of the power module can be relatively easily ensured and the safety in subsequent operation Be guaranteed. Preferably, this control check is performed automatically.

According to an advantageous development can be provided that the Kühlvorrich device is designed as a load-bearing, coolant durchströmbare cooling plate. In this embodiment, the cooling device is designed as a load-bearing Konstruktionsele element in the form of a cooling plate, with a great advantage is that a support function of the power assembly can be exercised on the frame and the cooling plate simultaneously forms a receiving platform for all arranged on the cooling device or cooling plate assemblies , The cooling plate thus serves as a kind of construction platform for receiving the energy, power semiconductor modules and any other components. Such components may be arranged, for example, in the form of an auxiliary assembly on the cooling plate and about a control device, power supplies, resistors and the like include sen. Depending on the structure and type of medium or high voltage converter, it may be advantageous to arrange at least one power semiconductor module on one side, such as the top, the cooling plate and the at least one energy storage assembly on the opposite side ge, such as the bottom, the To arrange cooling plate. Analogously, "standing" cooling plates are conceivable. Furthermore, this training can contribute to the local heat dissipation of the electrical components, in particular the power semiconductor group, to ensure very efficient and at the same time chen ermögli a space-saving arrangement several rer power modules in the frame of the medium or high voltage converter. The receiving spaces and / or support surfaces on which the cooling plate is supported, are electrically isolated from each other to avoid short circuits between individual power assemblies.

In particular, it may be advantageous if the energy storage module is arranged on one of at least one power semiconductor module and the at least two busbars gegenüberlie ing side of the cooling plate, wherein the cooling plate has a through hole for connecting the energy storage assembly with the at least one Leistungshalbleiterbau group.

In this way, the cooling plate can form an explosion protection effect between the electrical components disposed on the respective sides. For putting in, by the, preferably in at least one direction, centrally arranged through opening a relatively simple electrical connection of the power semiconductor module to the energy storage module, preferably via a connection terminal which includes the busbars, allows. As a result, on the one hand very short electrical links between the current-carrying components and in consequence a reduction and / or Ho mogenisierung of parasitic capacitances and / or inductances allows. Thus, this measure can contribute significantly to improving EMC.

For a better understanding of the invention, this will be explained in more detail with reference to the following figures.

In each case, in a highly simplified, schematic representation:

Figure 1 is a schematic representation of a power assembly with electrical compo th and connecting element.

Fig. 2 is a schematic oblique view of a possible arrangement of electrical compo th on the cooling device with different possible Verbindungspositio NEN of the connecting element;

Fig. 3 shows various possible embodiments of the power assembly with connec tion positions the busbars penetrating (a), (d) and / or arranged centrally (b), or on a connecting lug (c);

Fig. 4 is a schematic oblique view of a possible embodiment of a power assembly with arranged on both sides of the cooling device energy and Lei processing semiconductor modules.

Introductoryly it should be noted that in the differently described embodiments, the same parts provided with the same reference numerals or the same component names who the, with the disclosures contained in the entire description mutatis mutandis to equivalent parts with the same reference numerals or the same component names who can. Also, the position information selected in the description, such as above, un th, laterally, etc. related to the immediately described and illustrated figure and these position information in a change in position mutatis mutandis to transfer to the new location. In Fig. 1 is a schematic representation of a power assembly 1 according to the invention for not specifically shown a medium or high voltage converter 2 is shown. The power module 1 comprises at least one power semiconductor module 3 and at least one energy storage module 5 and at least one cooling device 7. The power semiconductor module 3 can be connected to the energy storage module 5, for example via busbars 10 and / or a connection terminal 14. Such arrangements are known in the art in detail and are shown only schematically here. The power supply and / or contacting with external power terminals is schematically indicated by means of egg ner busbar 13. The generally planar formed busbars 10 are separated by an insulating layer 12. The high-frequency changing electrical cal potential of the bus bars 13 may lead to the unwanted storage of electrical charge between the bus bars 13 and other mainly flat components of the power assembly 1. This is among other things as parasitic capacitance 18 be distinguished and is with the corresponding symbols and dashed lines between rule possible electrical components of the power assembly 1, at which such parasitic capacitances 18 may occur indicated.

The schematic representation in Fig. 1 allows to understand the operating principle of the inventively constructed power assembly 1, in which a cooling device 7 is electrically conductive and on which the at least one Leistungshalbleiterbau group 3 is preferably arranged directly heat transfer. The power semiconductor group 3 comprises at least one power semiconductor 4, such as an IGBT or similar suitable electronic components. To protect against the environment is a Schutzge housing 19 connected to the cooling device 7. To improve the electromagnetic compatibility according to the invention a defined Umladepfad 17 or current path between tween at least the cooling device 7 and one of the busbars 10 by means of a connecting element 15 is formed. The Umladepfad 17 shown in dashed lines is formed at a suitable connection position 16 by means of a connecting element 15. According to the attachment of the connecting element 15 as the last, electrically effective element of the power assembly 1. This is done by an insertion 20 in the protective housing 19 it allows. In this way, a defined current or Umladepfad 17 for unavoidable, parasitic discharge currents are created and the influence of parasitic capacitances 18 can be largely reduced or even avoided at undesirable points, whereby the EMC as well as defects and / or material degradation of individual components can be reduced.

The principle of the formation of a defined Umladepfads 17 by attaching the connec tion elements 15 to a predetermined connection position 16 of Fig. 1 is transferable to Figs. 2 to 4 and will be explained below on some possible embodiments on.

The connecting element 15 shown by way of example as a screw in FIG. 1, as in FIG. 2 in conjunction with FIG. 3, can be arranged to electrically connect at least one of the busbars 10 to the cooling device 7, wherein at least one of the busbars 10 is contacted. In FIG. 2, two semiconductor power semiconductor modules 3 are arranged, for example, on opposite sides of the busbars 10. Such an arrangement allows short electrical conduction paths and thus improves the electromagnetic compatibility by reducing parasitic inductances. In Fig. 2 it is further apparent that the connection position 16 between the cooling device 7 and cooling plate 8 to at least one of the bus bars at different positions is possible. For example, the connection Posi tion 16 on a laterally on one of the busbars 10 protruding terminal lug 11 for con tact of the connecting element 15 to the cooling plate 8 may be formed.

With reference to the preceding discussion of Fig. 1 and 2, further exemplary embodiments of inventive Feistungsbau groups 1 in Figs. 3a to 3d are shown. The busbars 10 may be shielded and / or supported from one another by an insulating layer 12, or to the cooling device through insulators 9.

Fig. 3a illustrates a schematic cross-sectional view, in which the vertically un direct busbar 10 is connected by the connecting element 15 to the conductive cooling device or cooling plate 8 From the illustration in Fig. 3a can be further seen that to the insertion opening 20 of the Protective housing 19 in the direction of the cooling device Einführele element 22 is formed. This preferably tubular or channel-shaped A guiding element 22 allows the loss-safe insertion and fastening of the Verbindungsele element 15th In Fig. 3b, a preferred possible embodiment of a connection position 16 is interpreted to, wherein the connection position in the middle 23 in a plane of the busbars 10 is arranged. In this case, the uppermost busbar 10 in the vertical direction is connected to the cooling device 7 or cooling plate 8 via the connecting element 15.

Another possible arrangement of the connecting element 15 can be seen from the Schnittdar position in Fig. 3c, wherein the connecting position 16 between a bus bar 10 and the cooling device 7 by means of a side of the bus bar excellent connection lug 11 is executed.

In Fig. 3d, a further and possibly independent embodiment of he inventive power module 1 is shown. In the exemplary illustration of FIG. 3d, the protective housing is designed to be electrically conductive and is electrically connected to the cooling device 7 and one of the busbars. The predetermined connection position 16 in this case comprises three points along the connecting element 15 at which electrical contacts are ausgebil det. In the illustrated situation, the insertion opening 20 of the protective housing 19 is closed at the same time with the attachment of the connecting element 15. Not dargesteht is a situation in which the electrical connection element 15 is formed as a partially insulating screw, wherein in the region of the shaft and / or head of the screw insulation ge compared to the protective housing is formed. In both cases, however, the Verbindungsele element 15 and provided for closing the insertion opening 20 closure element 21 is integrally formed.

The connecting elements 15 may have an electrically conductive cross section, wel holes simultaneously contributes to a targeted heat dissipation to the cooling device. In particular, it may be advantageous if the effective cross-section is formed by at least 10% larger than the required minimum cross-section for the electrical connection and formation of the defi ned Umladepfads 17. Moreover, in screw-like connecting elements 15, as can be seen, for example, in FIGS. 3a-3c, a widened screw head can be used for an improved support or contacting of the busbar 10, whereby increased heat absorption or heat dissipation can be promoted. FIG. 4 shows a schematic oblique view of a power module 1. In the selected representation, it can be seen that the at least one power semiconductor module 3 and the at least one energy storage module 5 are arranged on opposite sides of the cooling plate 8. A connection of the energy storage module 5 with the power semiconductor module 3 and / or an auxiliary module 24 is possible through the formation of a cooling plate 8 penetrating through opening 25. In the area of this through-opening 25 can preferably be a connection terminal 14 for connecting the electrical components rule. Such a situation is especially advantageous in connection with an arrangement of the components of the power module 1 which is symmetrical in the transverse direction and / or the longitudinal direction, as is indicated schematically in FIG. 2, for example. Through one or more passage openings 25, the electrical connection paths can be selected relatively short.

Furthermore, it can be seen from FIG. 4 that a separate closure element 21 can be provided for closing the insertion opening 20 of the protective housing 19. A derarti ges closure element 21 is provided as an electrically non-effective element and serves the completion of the protective housing 19 relative to the environment.

For the expert is easily apparent from the illustrations of FIGS. 1 to 4 that inven tion according to any electrical tests on various, predetermined insulation distances can be performed a fold before and / or after the attachment of Schutzgehäu ses 19 is done.

About this can be seen in Fig. 4 that a symmetrical arrangement of the electrical components allows the formation of approximately equal length of current paths. This favors the reduction of the influence of parasitic capacitances and / or inductances and improves the EMC. This is of particular advantage in the case of flat busbars 10 and / or busbars 13, which would tend to form a parasitic capacitance 18 with respect to a protective housing 19 and / or the electrically conductive cooling plate 8.

The exemplary embodiments show possible embodiments, wherein it should be noted at this point that the invention is not limited to the specifically illustrated embodiment variants. Ben is limited, but rather also various combinations of the individual Ausfüh insurance variants with each other are possible and this possibility of variation due to the doctrine of technical action by objective invention in the skill of working in this technical field expert.

The scope of protection is determined by the claims. However, the description and drawings are to be considered to interpret the claims. Individual features or feature combinations from the illustrated and described different Ausführungsbeispie len can represent for themselves inventive solutions. The independent inventive solutions underlying task can the description taken from who the.

All information on ranges of values in the present description should be understood to include any and all sub-ranges thereof, e.g. is the statement 1 to 10 to be understood that all sub-areas, starting from the lower limit 1 and the upper limit 10 are included, ie. all sub-areas begin with a lower limit of 1 or greater and end at an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1, or 5.5 to 10.

For the sake of order, it should finally be pointed out that, for a better understanding of the structure, elements have been partially rendered out of scale and / or enlarged and / or reduced Darge.

Reference symbol Power module

Medium or high voltage

judge

Power semiconductor device

Power semiconductor

Energy storage module

energy storage

cooler

cooling plate

insulator

busbar

terminal lug

Isolation layer

conductor rail

connection terminal

connecting element

connection position

Umladepfad

parasitic capacity

housing

insertion

closure element

insertion

Middle of the Busbarebene

auxiliary assembly

Through opening

Claims

Patent claims

Power module (1) for a medium or high voltage converter (2), in particular a modular multilevel converter, comprising:

at least one power semiconductor module (3),

at least one energy storage module (5),

at least one cooling device (7),

at least two busbars (10),

characterized in that

the cooling device (7) is electrically conductive, and with a, at least the power semiconductor assembly (3) against the environment shielding, protective housing (19) is connected, which has at least one insertion opening (20) for insertion and fastening conditions of a connecting element (15) .

and at a predetermined connection position (16) an electrically conductive Verbindungsele element (15), for forming a defined Umladepfads (17), between at least the cooling device (7) and one of the busbars (10) is arranged.

2. Power assembly (1) according to claim 1, characterized in that the Ver binding selement (15) releasably, preferably as a screw, plug or locking element, is formed.

3. power assembly (1) according to claim 1 or 2, characterized in that the connecting element (15) has a cross section which is formed by more than 10%, before given to more than 20% greater than a charge for the formation of the defined order (17) and a derivation of parasitic discharge currents at least required Min least cross section is required.

4. Power module (1) according to one of the preceding claims characterized in that at least two power semiconductor modules (3) are arranged on at least two times on a plane of the busbars (10) aligned sides of the busbars (10), preferably opposite one another.

5. Power module (1) according to one of the preceding claims characterized in that the connecting element (15) at least one of the busbars (10) with the Cooling device (7) electrically connecting and the at least one other busbar (10) penetrating and electrically insulating it is arranged.

6. power assembly (1) according to claim 5, characterized in that the Ver binding selement (15) in the middle (23) of the plane of the busbars (10) is arranged.

7. power assembly (1) according to one of claims 1 to 4 characterized in that at least one of the busbars (10) has a laterally projecting terminal lug (11) for contacting the connecting element (15).

8. power module (1) according to one of the preceding claims characterized in that a, preferably as a channel or tubular, insertion element (22), at least partially from the insertion opening (20) of the protective housing (19) in the direction of the nearest busbar (10) is formed extending.

9. power assembly (1) according to one of the preceding claims characterized in that the insertion opening (20) by means of a closure element (21), preferably a plug or a screw, is closed.

10. Power assembly (1) according to one of the preceding claims characterized in that the protective housing (19) is electrically conductive and electrically connected to the cooling device (7).

11. Power assembly (1) according to claim 10, characterized in that the connecting element (15) is arranged such that protective housing (19) with the Kühlvorrich device (7) and one of the busbars (10) is electrically connected.

12. Power assembly (1) according to one of the preceding claims characterized in that the cooling device (7) is designed as a load-bearing, coolant-flowable cooling plate (8).

13. power module (1) according to claim 12, characterized in that the energy storage module (5) on one of the at least one power semiconductor module (3) and the at least two busbars (10) opposite side of the cooling plate (8) is arranged, wherein the cooling plate (8) has a through hole (25) for connecting the Energiespei cherbaugruppe (5) with the at least one power semiconductor assembly (3).

14. A method for producing a power assembly (1), in particular for a medium or high voltage converter (2), comprising the method steps:

- Provision of a power module (1) according to one of claims 1 to 13, comprising at least

- Attaching a, at least the power semiconductor assembly (3) from the environment final, protective housing (19) on the cooling device (7) having at least one insertion opening (20) for inserting and fixing a connecting element (15),

- Forming a defined Umladepfads (17) by attaching the connecting element (15) at a predetermined connection position (16) between at least the cooling device (7) and one of the busbars (10) through the insertion opening (20).

15. The method according to claim 14, characterized in that with or after the attachment of the connecting element (15), the insertion opening (20) by means of a Verschlus selements (21), preferably a plug or a screw, is closed.

16. The method according to claim 15, characterized in that by the Anbrin movement of the connecting element (15), the insertion opening (20) is closed and the United connection position (16) between at least the cooling device (7) and one of the busbars (10) and the protective housing (19) is formed.

17. The method according to any one of claims 14 to 16, characterized in that prior to attachment of the protective housing (19) a first electrical test of Leistungsbau group (1) by applying a first test voltage on at least one predetermined Isolati onsstrecke is performed.

18. The method according to claim 17, characterized in that after the first test and / or after the attachment of the protective housing (19) a second electrical test of the power assembly (1) by applying a, relative to the first test voltage increased, second test voltage at least one specifiable insulation distance is performed.

19. The method according to any one of claims 14 to 18, characterized in that between one of the busbars (10) and the cooling device (7) and / or the protective housing (19) a control check with regard to the functionality and / or the presence of the connecting element (15) is made