CN117957625A - DC-supported film capacitor with spring connector for power converters, particularly inverters - Google Patents

Abstract

A DC support capacitor (17, 17 a..17 j) for a power converter (18, 18a, 18 b) is specified, having a busbar arrangement (6 a..6 d) consisting of two bent sheet metal parts (4 a..4 d, 5 a..5 d), which are inserted one into the other and are electrically insulated from each other and comprise a plurality of contact lugs (7 a..10 d) as a result of bending from a sheet metal plane (A, B). Furthermore, the DC support capacitor (17, 17 a..17 j) comprises a plurality of parallel-connected film capacitor elements (1 a..1 l), with capacitor contacts (3 a..3 j), which are embodied as flat lug-shaped spring contacts. In the mounted state, the capacitor contacts (3 a..3j) are resiliently supported on contact lugs (7 a..10d) of the bent sheet metal parts (4 a..4 d, 5 a..5 d). Furthermore, a power converter (18, 18a, 18 b) comprising such a DC support capacitor (17, 17 a..17 j) and an electric vehicle (24) comprising such a power converter (18, 18a, 18 b) are specified.

Description

DC-supported film capacitor with spring connector for power converters, particularly inverters

Technical Field

The present invention relates to a DC support capacitor for a power converter, a power converter comprising such a DC support capacitor, and an electric vehicle comprising such a power converter configured as an inverter.

Background

Power converters, particularly inverters, such as are used in electric drives in electric vehicles, include a Direct Current (DC) support capacitor for smoothing DC voltage from a DC voltage source, such as a rechargeable battery or fuel cell. DC support capacitors typically comprise a plurality of individual capacitors that are soldered or welded to each other in order to obtain the desired total capacitance. This can be achieved in particular by using separate conductors which electrically connect the individual capacitors to each other. The problem here is that the production of the DC support capacitor according to the known method is relatively complex and the known DC support capacitor has a relatively large volume with respect to its capacitance. In addition, it is not easy to produce a DC support capacitor with a variable capacitance. Further, it takes a relatively long time to manufacture the DC support capacitor having the welded film capacitor element because the bus bar device equipped with the film capacitor element must be introduced into the welding robot to perform the welding process.

Disclosure of Invention

It is therefore an object of the present invention to provide an improved DC support capacitor for a power converter, an improved power converter and an improved electric vehicle. In particular, the object of the present invention is to specify a solution which simplifies the production of DC support capacitors, makes it possible to simply produce DC support capacitors with variable capacitance, and makes it possible to produce DC support capacitors with a small volume relative to their capacitance.

The object of the invention is achieved by a DC support capacitor for a power converter, in particular an inverter, comprising:

a) A busbar arrangement having a first bent sheet metal part with a first sheet metal plane and a second bent sheet metal part electrically insulated therefrom with a second sheet metal plane aligned parallel to the first sheet metal plane,

Wherein the second bent sheet metal part is electrically insulated from the first bent sheet metal part by means of an insulating layer arranged between the sheet metal planes,

Wherein the first curved sheet metal part and the second curved sheet metal part each comprise a plurality of contact lugs which are arranged on the edges of the respective sheet metal and which occur as a result of bending from the sheet metal plane or as a result of separating the respective sheet metal along a U-shaped separation line and bending from the sheet metal plane, and

-Wherein at least some of the contact lugs of the first (lower) bent sheet metal part are guided through cutouts in the second (upper) bent sheet metal part, and

B) A plurality of film capacitor elements, each having a wound metallized plastic film and first and second capacitor contacts electrically connected thereto,

Wherein the capacitor contacts are embodied as flat lug-type spring contacts (which may consist in particular of aluminum and/or copper or may comprise these elements),

-Wherein the first capacitor contacts are each resiliently supported on a respective contact lug of the first bent metal sheet part, the second capacitor contacts are each resiliently supported on a respective contact lug of the second bent metal sheet part, and

-Wherein the individual film capacitor elements are electrically connected in parallel.

The object of the invention is also achieved by a power converter comprising a power converter housing and a DC support capacitor according to the above disclosed type, wherein the film capacitor element is arranged directly on the power converter housing.

In particular, the power converter may be configured as an inverter and have a power section with a plurality of controllable switches electrically connected to a DC support capacitor, wherein the DC support capacitor is provided for smoothing a DC voltage of the DC voltage source, and wherein the power section is provided for generating an AC voltage from the DC voltage smoothed by the DC support capacitor.

Finally, the object of the invention is also achieved by an electric vehicle having an inverter of the aforementioned type, a DC voltage source connected to the DC support capacitor and an electric drive connected to the power section, wherein the electric drive is mechanically coupled to the wheels of the electric vehicle.

Thanks to the proposed measures, the production of the DC support capacitor is simplified, so that a DC support capacitor with a variable capacitance can be produced simply, and so that a DC support capacitor with a small volume with respect to its capacitance can be produced. This is achieved primarily by a film capacitor element having capacitor contacts embodied as flat lug spring contacts. As a result, the film capacitor element is electrically contacted with the bus bar arrangement by simply inserting it. For example, the capacitor contacts may have a resilient straight cross-section, but it is also conceivable that these are embodied as arc-shaped cross-sections. In addition, the film capacitor element may have insulation that wraps around the metallized plastic film.

Since the soldering or brazing of the capacitor contacts to the contact lugs of the busbar arrangement can be omitted, the film capacitor elements can be arranged very close to each other, as a result of which a high capacitance of the DC support capacitor is obtained while at the same time a small volume is obtained. Furthermore, the bus bar arrangement can be equipped with film capacitor elements alone in a simple manner, so that a DC support capacitor with a variable capacitance can be produced in a simple manner.

Furthermore, a simple production of the busbar arrangement itself is also possible. The busbar arrangement comprises two bent sheet metal parts inserted one into the other. An insulating layer is disposed between the first bent sheet metal member and the second bent sheet metal member and is used to electrically insulate the second bent sheet metal member from the first bent sheet metal member. For example, the insulating layer may be formed of a plastic film laminated onto the first bent metal sheet part and/or the second bent metal sheet part. It is also possible to use laminated bent sheet metal parts having an open (non-insulating) surface only at the contact points with the capacitor contacts or the film capacitor element, which surface is under voltage during operation. This results in a composite or sandwich structure of bent sheet metal parts and insulating layers. In order to minimize leakage inductance, the insulating layer should be as thin as possible. The DC support capacitor also has electrical connections assigned to the bent sheet metal components. For example, for this purpose, the bent sheet metal part comprises optional connection lugs for the electrical connection of the DC support capacitor. For example, in a ready-to-operate arrangement, a first bent sheet metal part may be connected or assigned to a positive pole, while a second bent sheet metal part may be connected or assigned to a negative pole or ground of the electrical system.

Further, compared with the welded film capacitor element, since the bus bar device equipped with the film capacitor element no longer needs to be introduced into the welding robot, the manufacturing time is shortened.

Further advantageous configurations and developments of the invention can be derived from the dependent claims and the description when considered in connection with the figures.

Advantageously, the first bent sheet metal part and/or the second bent sheet metal part are configured as stamped bent sheet metal parts, and the cutout is formed by a stamped part and/or by bending the contact lugs from the sheet metal plane. As a result, the first bent metal sheet part and the second bent metal sheet part can be efficiently produced. This applies in particular to the case where the cut-out in the second (upper) bent sheet metal part is formed by bending the contact lug from the sheet metal plane, through which cut-out the contact lug of the first (lower) bent sheet metal part is guided, since the bending of the contact lug and the production of the above-mentioned cut-out can be carried out in one (single) production step. While stamping and bending constitute an advantageous production process for the first and second bent sheet metal parts, it is also conceivable to use other techniques for producing the first and second bent sheet metal parts. For example, the bent sheet metal part may also be laser cut or plasma cut.

Furthermore, it is advantageous that (all) contact lugs for contacting the film capacitor element:

-aligned parallel to each other, and/or

-Aligned at right angles to the plane of the metal plate.

As a result, firstly, the production process of the sheet metal component is simplified, and secondly, as a result, the film capacitor elements inserted into the bus bar device are also arranged parallel to each other, thereby also simplifying the insertion of the film capacitor elements into the bus bar device.

Advantageously, the capacitor contacts of the film capacitor elements in the film capacitor element are directly opposite to each other with respect to the normal of the contact lugs for contacting the film capacitor elements. In other words, both capacitor contacts of the film capacitor element are located on the normal of the contact lugs. As a result, the (mechanical) forces caused by the spring contacts of the film capacitor element inserted into the busbar arrangement are also located on the line of action, so that no torque acts on the film capacitor element inserted into the busbar arrangement. As a result, no special measures need to be implemented to prevent undesired rotation of the film capacitor element.

However, it is also advantageous if the capacitor contacts of the film capacitor elements in the film capacitor element are laterally offset from one another with respect to the normal of the contact lugs for contacting the film capacitor elements. As a result, the contact lugs of the first bent sheet metal part and the contact lugs of the second bent sheet metal part or the contact lugs of different electrical polarities are at a relatively large distance from each other and thus are electrically well insulated from each other.

Advantageously, the film capacitor element:

implemented without a housing and wrapped by insulation (alone),

Each enclosed in a separate housing, or

Having a common DC supporting capacitor housing, in particular in which the film capacitor element is encapsulated.

For example, the insulation for the film capacitor element may be composed of or include a resin, and may be embodied to be liquid-impermeable. The insulation may be made by encapsulation by injection molding, cladding or encapsulation. The encapsulation itself can be carried out without a housing in the mould or with the aid of a separate housing. In this case, the respective housings can be assigned to the respective film capacitor elements, as a result of which the film capacitor elements are each packaged in a separate housing, or a plurality of, in particular all, film capacitor elements of the DC support capacitor are packaged in a housing, as a result of which a plurality of (or all) film capacitor elements have a common DC support capacitor housing.

It is particularly advantageous if the insertion locations of the film capacitor elements in the busbar arrangement are arranged in rows and columns, wherein the contact lugs directly adjacent to one another in rows are alternately part of the first curved sheet metal part or the second curved sheet metal part, and wherein the contact lugs directly below one another in columns are likewise alternately part of the first curved sheet metal part or the second curved sheet metal part. During operation of the DC support capacitor, a first electrical polarity is assigned to the first bent sheet metal part and an opposite second electrical polarity is assigned to the second bent sheet metal part. Thus, the insertion positions arranged next to each other in a row have contact lugs each having alternating polarity, and the insertion positions located directly below each other in a column also have contact lugs also having alternating polarity. As a result, the magnetic fields of adjacent film capacitor elements due to current flowing through the contact lugs of the respective bent sheet metal components and through the capacitor contacts and Schoop layers of the individual film capacitor elements are each counter-aligned. The Schoop layers are usually winding-side metallization layers, made of wound metallized plastic film, for contacting the capacitor contacts. Even in the case of a relatively large single film capacitor element, the magnetic field compensation by the current flowing along the end face/Schoop layers enables a low-inductance overall structure.

The above-described configurations and developments of the invention can be combined in any desired manner.

Drawings

Exemplary embodiments of the invention are illustrated by way of example in the accompanying drawings. In the drawings:

fig. 1 is a schematic diagram showing a first example of a film capacitor element in an oblique view;

fig. 2 is a schematic diagram showing a second example of the film capacitor element in an oblique view;

FIG. 3 is a view, for example, illustrating the bent sheet metal component of the first bus bar assembly in an exploded view;

FIG. 4 is the bus bar assembly of FIG. 3 in an assembled state;

FIG. 5 is the bus bar assembly of FIG. 4 in a partially armed state;

FIG. 6 is the bus bar assembly of FIG. 3 with insulating plates between contact lugs of the bent sheet metal component;

FIG. 7 is the bus bar assembly of FIG. 6 with insulation around the bent sheet metal components;

FIG. 8 shows the bus bar arrangement of FIG. 7 with one filter capacitor element in an exploded view;

FIG. 9 shows the bus bar arrangement of FIG. 7 fully equipped with filter capacitor elements in an oblique view;

FIG. 10 shows the bus bar arrangement of FIG. 7 with an alternate filter capacitor element in an exploded view;

FIG. 11 shows the bus bar arrangement of FIG. 7 fully equipped with an alternative filter capacitor element in an oblique view;

FIG. 12 shows the bus bar arrangement of FIG. 7 fully equipped with an alternative filter capacitor element in a side view;

fig. 13 shows the busbar arrangement in fig. 7 fully equipped with an alternative filter capacitor element in a plan view;

FIG. 14 illustrates, for example, in an exploded view, a bent sheet metal component of the second bus bar assembly;

FIG. 15 shows the bus bar assembly of FIG. 14 in an assembled state;

FIG. 16 shows the bus bar assembly of FIG. 15 with insulating plates between the contact lugs of the bent sheet metal component;

FIG. 17 shows the bus bar arrangement of FIG. 16 with one filter capacitor element in an exploded view;

FIG. 18 shows the bus bar arrangement of FIG. 16 fully equipped with filter capacitor elements in an oblique view;

FIG. 19 shows the bus bar arrangement of FIG. 16 with an alternate filter capacitor element in an exploded view;

FIG. 20 shows the bus bar arrangement of FIG. 16 fully equipped with filter capacitor elements in an oblique view;

FIG. 21 is a view, for example, illustrating the bent sheet metal component of the third bus bar assembly in an exploded view;

FIG. 22 is the bus bar assembly of FIG. 21 in an assembled state;

FIG. 23 shows the bus bar assembly of FIG. 22 with insulating plates between the contact lugs of the bent sheet metal component;

FIG. 24 shows the bus bar arrangement of FIG. 23 with one filter capacitor element in an exploded view;

fig. 25 shows the busbar arrangement in fig. 23 fully equipped with filter capacitor elements in an oblique view;

FIG. 26 shows the bus bar arrangement of FIG. 23 with an alternate filter capacitor element in an exploded view;

FIG. 27 shows the bus bar arrangement of FIG. 23 fully equipped with an alternative filter capacitor element in an oblique view;

FIG. 28 is a view, for example, illustrating the bent sheet metal component of the fourth bus bar assembly in an exploded view;

FIG. 29 is the bus bar assembly of FIG. 28 in an assembled state;

FIG. 30 shows the bus bar assembly of FIG. 29 with insulating plates between the contact lugs of the bent sheet metal component;

FIG. 31 shows the bus bar assembly of FIG. 30 with one filter capacitor element in an exploded view;

fig. 32 shows the busbar arrangement in fig. 30 equipped with filter capacitor elements in an oblique view;

FIG. 33 shows the bus bar arrangement of FIG. 30 with an alternate filter capacitor element in an exploded view;

FIG. 34 shows the bus bar arrangement of FIG. 30 fully equipped with an alternative filter capacitor element in an oblique view;

Fig. 35 is a first example of the power converter viewed from obliquely above;

Fig. 36 is a second example of the power converter viewed obliquely from below; and

Fig. 37 is an exemplary and schematically illustrated electric vehicle.

Detailed Description

The same components in the different embodiments will be described by way of introduction with the same reference numerals or the same constituent component names, with different reference numerals where appropriate. The disclosure of one constituent part contained in the specification may be transferred to another constituent part having the same reference numeral or the same constituent part name accordingly. Furthermore, the positional indications selected in the description, such as "top", "bottom", "rear", "front", "side", etc., are relevant to the directly described and illustrated drawings, and should be transferred to the new position accordingly if the position changes.

Fig. 1 shows a first example of a film capacitor element 1a with a wound metallized plastic film 2 and two capacitor contacts electrically connected thereto for contacting a busbar or busbar arrangement, wherein the capacitor contacts are embodied as flat lug-type spring contacts and can consist in particular of aluminum and/or copper or can comprise these elements. Only one capacitor contact, namely capacitor contact 3a, is visible in fig. 1. Furthermore, the film capacitor element 1a comprises an insulation (not explicitly shown in fig. 1) surrounding the metallized plastic film 2.

In fig. 1, the capacitor contact 3a is bent in a sharp-edged manner and has a straight cross section. However, this is not necessarily the case. Fig. 2 shows another example of a film capacitor element 1b, which is very similar in construction to the film capacitor element 1a of fig. 1. However, in contrast, the cross section of the capacitor contact 3b is arcuate.

Fig. 3 shows the first bent sheet metal part 4a and the second bent sheet metal part 5a of the busbar arrangement 6a in an exploded view. The first bent sheet metal part 4a has a first sheet metal plane a and the second bent sheet metal part 5a has a second sheet metal plane B, which are aligned parallel to each other.

The first bent sheet metal part 4a comprises a plurality of contact lugs 7a and a plurality of contact lugs 8a, the contact lugs 7a being arranged at the edges and emerging from bending from the first sheet metal plane a, the contact lugs 8a emerging from the first bent sheet metal part 4a being separated along a U-shaped separation line and from bending from the first sheet metal plane a.

The second bent sheet metal part 5a likewise comprises a plurality of contact lugs 9a and a plurality of contact lugs 10a, the contact lugs 9a being arranged at the edges and emerging from bending from the second sheet metal plane B, the contact lugs 10a emerging from the second bent sheet metal part 5a being separated along a U-shaped separation line and bent from the second sheet metal plane B.

In particular, it is also conceivable for the first bent sheet metal part 4a to have only the contact lugs 8a and/or for the second bent sheet metal part 5a to have only the contact lugs 10a, that is to say no edge contact lugs 7a, 9a.

Some of the contact lugs 7a, 8a of the first (lower) bent sheet metal part 4a are guided through the cutouts 11a in the second (upper) bent sheet metal part 5a, as shown by the broken lines in fig. 3 and the results in fig. 4. Specifically, fig. 4 shows an oblique view of the finished busbar apparatus 6a arranged on the substrate 14.

An insulating layer (not shown in detail) is arranged between the first bent sheet metal part 4a and the second bent sheet metal part 5a, and serves to electrically insulate the second bent sheet metal part 5a from the first bent sheet metal part 4 a. For example, the insulating layer may be formed of a plastic film laminated onto the first bent metal sheet part 4a and/or the second bent metal sheet part 5a. It is also possible to use laminated bent sheet metal parts 4a, 5a having an open (non-insulating) surface only at the contact points with the capacitor contacts 3a or the film capacitor element 1 a. Thereby creating a composite or sandwich of bent sheet metal parts 4a, 5a and insulating layers. In order to minimize leakage inductance, the insulating layer should be as thin as possible.

Finally, the first bent sheet metal part 4a comprises optional connection lugs 12a and the second bent sheet metal part 5a comprises optional connection lugs 13a for electrical connection of the busbar arrangement 6 a. For example, in a ready-to-operate arrangement, the first bent sheet metal part 4a may be connected to or form a positive pole, while the second bent sheet metal part 5a may be connected to or form a negative pole or ground of the electrical system.

Fig. 5 shows a purely exemplary possibility of equipping the busbar arrangement 6 a. For example, the film capacitor element 1c or 1d may be inserted between the contact lugs 7 a..10a. For the film capacitor element 1d, the case of the insulating or film capacitor element 1d surrounding the metallized plastic film 2 is explicitly shown in this example. Insulation plates 15 may be provided between the contact lugs 7 a..10a to prevent accidental shorting between the contact lugs 7 a..10a at different voltage levels. It should be noted that fig. 5 is only intended to clarify the various possibilities of equipping the busbar arrangement 6a, but the busbar arrangement 6a is not normally equipped in this form. Instead, this is typically done in a homogenous manner.

In this respect, fig. 6 shows a busbar arrangement 6a in which all contact lugs 7 a..10 a are electrically insulated from each other by insulating plates 15.

Fig. 7 shows a busbar arrangement 6a in which a first bent sheet metal part 4a and a second bent sheet metal part 5a are encapsulated with insulation 16. The insulation 16 may also perform an electrical insulation function between the first bent sheet metal part 4a and the second bent sheet metal part 5 a.

Fig. 8 shows an exploded view of the busbar arrangement 6a of fig. 7 with one film capacitor element 1 c. Fig. 9 shows the bus bar device 6a fully equipped with the film capacitor element 1 c. In this case, the first capacitor contacts 3c are each resiliently supported on a respective contact lug 7a, 8a of the first bent sheet metal part 4a, and the second capacitor contacts are each resiliently supported on a respective contact lug 9a, 10a of the second bent sheet metal part 5 a. At the same time or as a result, the individual film capacitor elements 1c are electrically connected in parallel. This results in a DC support capacitor 17a for the power converter, in particular the inverter.

Fig. 10 and 11 correspond to fig. 8 and 9, but the film capacitor element 1c is replaced with a film capacitor element 1 d. This results in a DC support capacitor 17b for the power converter, in particular the inverter. Fig. 12 shows a side view of the DC support capacitor 17b in addition, and fig. 13 shows a plan view of the DC support capacitor 17b.

In summary, the DC support capacitors 17a, 17b for the power converter comprise:

a) A busbar arrangement 6a having a first bent sheet metal part 4a with a first sheet metal plane A and a second bent sheet metal part 5a electrically insulated therefrom with a second sheet metal plane B aligned parallel to the first sheet metal plane A,

Wherein the second bent sheet metal part 5a and the first bent sheet metal part 4a are electrically insulated from each other by means of an insulating layer arranged between the sheet metal planes A, B, and

Wherein the first bent sheet metal part 4a and the second bent sheet metal part 5a each comprise a plurality of contact lugs 7 a..10a, which are arranged on the edges of the respective sheet metal and which occur as a result of bending from the sheet metal plane A, B or as a result of separating the respective sheet metal along a U-shaped separation line and bending from the sheet metal plane A, B, and

Wherein at least some of the contact lugs 7a, 8a of the first (lower) bent sheet metal part 4a are guided through the cutouts 11a in the second (upper) bent sheet metal part 5a, and

B) A plurality of film capacitor elements 1 a..1d, each having a wound metallized plastic film 2 and first and second capacitor contacts 3 a..3d electrically connected thereto,

Wherein the capacitor contacts 3 a..3 d are embodied as flat lug-type spring contacts,

Wherein the first capacitor contacts 3 a..3 d are each resiliently supported on a respective contact lug 7a,8a of the first bent sheet metal part 4a and the second capacitor contacts are each resiliently supported on a respective contact lug 9a,10a of the second bent sheet metal part 5a, and

Wherein the individual film capacitor elements 1 a..1d are electrically connected in parallel.

Then, fig. 14 to 20 show further examples of the configuration of the DC support capacitors 17c, 17 d.

Similar to fig. 3, fig. 14 shows the first bent sheet metal part 4b and the second bent sheet metal part 5b of the busbar arrangement 6b in an exploded view. The characteristics of the busbar arrangement 6b are very similar to those of the busbar arrangement 6a in fig. 3, which is why only the relevant differences between the busbar arrangement 6b and the busbar arrangement 6a are discussed below.

First, the first bent sheet metal part 4b includes edge contact lugs 7b', which are not provided only for contacting one film capacitor element 1e, 1f, but are designed for contacting a plurality of film capacitor elements 1e, 1f. Next, the contact lugs 7b and 8b of the first bent sheet metal part 4b are guided through the cutouts 11b 'in the second bent sheet metal part 5b, the cutouts 11b' being shaped by bending the contact lugs 7b and 8b from the first sheet metal plane a. Furthermore, the busbar arrangement 6b is designed to receive only six film capacitor elements 1e, 1f, although it can of course also be made larger.

Similar to fig. 4, fig. 15 shows bent sheet metal parts 4b and 5b connected together to form a busbar arrangement 6 b; similar to fig. 6, fig. 16 shows a bus bar device 6b equipped with an insulating plate 15. Fig. 17 shows the insertion of the film capacitor element 1e like fig. 8, and fig. 18 shows the bus bar device 6b equipped with the film capacitor element 1e like fig. 9, with the result that the DC support capacitor 17c appears. Fig. 19 shows the insertion of the film capacitor element 1f like fig. 10, and fig. 20 shows the bus bar device 6b equipped with the film capacitor element 1f like fig. 11, with the result that the DC support capacitor 17d appears.

Then, fig. 21 to 27 show further examples of the configuration of the DC support capacitors 17e, 17 f.

Similar to fig. 14, fig. 21 shows the first bent sheet metal part 4c and the second bent sheet metal part 5c of the busbar arrangement 6c in an exploded view. The features of the busbar arrangement 6c are very similar to those of the busbar arrangement 6b in fig. 14. In particular, the insertion direction of the film capacitor elements 1g, 1h has now changed, as a result of which the second (upper) bent sheet metal part 5c can be made slightly smaller.

Similar to fig. 15, fig. 22 shows bent sheet metal parts 4c and 5c joined together to form a busbar arrangement 6 c; similar to fig. 16, fig. 23 shows a bus bar device 6c equipped with an insulating plate 15. Fig. 24 shows the insertion of the film capacitor element 1g similarly to fig. 17, and fig. 25 shows the bus bar device 6c equipped with the film capacitor element 1g similarly to fig. 18, with the result that the DC support capacitor 17e appears. Fig. 26 shows the insertion of the film capacitor element 1h similarly to fig. 19, and fig. 27 shows the bus bar device 6c equipped with the film capacitor element 1h similarly to fig. 20, with the result that the DC support capacitor 17f appears.

Then, fig. 28 to 34 show further examples of the configuration of the DC support capacitors 17g, 17 h.

Similar to fig. 14, fig. 28 shows the first bent sheet metal part 4d and the second bent sheet metal part 5d of the busbar arrangement 6d in an exploded view. The features of the busbar arrangement 6d are very similar to those of the busbar arrangement 6b in fig. 14. In particular, alternating insertion directions of the film capacitor elements 1i, 1j are provided in this case.

Similar to fig. 15, fig. 29 shows bent sheet metal parts 4d and 5d joined together to form a busbar arrangement 6 d; similar to fig. 16, fig. 30 shows a bus bar device 6d equipped with an insulating plate 15. Fig. 31 shows the insertion of the film capacitor element 1i like fig. 17, and fig. 32 shows the bus bar device 6d equipped with the film capacitor element 1i like fig. 18, with the result that the DC support capacitor 17g appears. Fig. 33 shows the insertion of the film capacitor element 1j similarly to fig. 19, and fig. 34 shows the bus bar device 6d equipped with the film capacitor element 1j similarly to fig. 20, with the result that the DC support capacitor 17h appears.

In the case of the DC support capacitor 17g shown in fig. 32 and the DC support capacitor 17h shown in fig. 34, the insertion positions of the film capacitor elements 1i,1j in the bus bar device 6d are arranged in a row, wherein the contact lugs 7 a..10 d immediately adjacent to each other in a row are alternately parts of the first bent metal plate member 4d or the second bent metal plate member 5d, and wherein the contact lugs 7 a..10 d located immediately below each other in a row are also alternately parts of the first bent metal plate member 4d or the second bent metal plate member 5d. During operation of the DC support capacitors 17g, 17h, a first electrical polarity is assigned to the first bent sheet metal part 4d, while an opposite second electrical polarity is assigned to the second bent sheet metal part 5d. Thus, the insertion positions arranged next to each other in rows have contact lugs 7 d..10d, each having alternating polarity, and the insertion positions arranged next to each other in columns also have contact lugs 7 d..10d, each also having alternating polarity. The magnetic fields of adjacent film capacitor elements 1i,1j and the layers of capacitor contacts 3i,3i' and Schoop of the respective film capacitor elements 1i,1j, which are generated by the current flowing through the contact lugs 7 d..10 d of the respective bent sheet metal parts 4d, 5d, are thus aligned in opposite directions. For contacting the capacitor contacts 3i,3i', the Schoop layers are usually the winding-end-side metallization layers, which are made of wound metallized plastic film. Even in the case of a relatively large single film capacitor element 1i,1j, the magnetic field compensation by the current flowing along the end face/Schoop layers enables a low-inductance overall structure.

The embodiments of the busbar arrangement 6 a..6 d and the DC support capacitor 17 a..17 h presented in the context of fig. 3 to 34 also have in common.

For example, the first bent sheet metal part 4 a..4d and/or the second bent sheet metal part 5 a..5 d may be configured as a stamped bent sheet metal part, and the slits 11 a..11 d' may be formed by stamping portions. As a result, the first bent metal sheet part 4 a..4d and the second bent metal sheet part 5 a..5 d can be efficiently produced. It is particularly advantageous that the cutouts are formed by bending contact lugs from the sheet metal plane A, B, as is the case with cutouts 11b ', 11c ' and 11d ' of busbar arrangements 6b, 6c and 6 d. In these cases, the bending of the contact lugs 7 b..10d and the production of the aforementioned cuts 11b ', 11c ' and 11d ' are effected in one (single) production step. While stamping and bending constitute an advantageous production process for the first bent sheet metal part 4 a..4 d and the second bent sheet metal part 5 a..5 d, it is also conceivable to use other techniques for producing the first bent sheet metal part 4 a..4 d and the second bent sheet metal part 5 a..5 d. For example, the first bent sheet metal part 4 a..4d and the second bent sheet metal part 5 a..5 d may also be laser or plasma cut.

Furthermore, the (all) contact lugs 7 a..10d for contacting the film capacitor element 1 a..1 j are aligned parallel to each other and at right angles to the sheet metal plane A, B in the case of the busbar arrangement 6 a..6 d. As a result, first, the metal plate members 4 a..4d, 5 a..5d are simplified, and second, as a result, the film capacitor elements 1 a..1j inserted into the bus bar device 6 a..6 d are also arranged parallel to each other, thereby also simplifying the insertion of the film capacitor elements 1 a..1 j into the bus bar device 6 a..6d. While these features are advantageous, it is also contemplated that the contact lugs 7 a..10 d of the busbar arrangement 6 a..6 d are not aligned parallel to each other and/or at right angles to the sheet metal plane A, B. In this case, the inserted film capacitor elements 1 a..1j are not all arranged parallel to each other, and as a result, in some cases, the space can be utilized better under the limited space condition.

In the case of the DC support capacitors 17a, 17b shown in fig. 9 and 11, the capacitor contacts 3c, 3d of the film capacitor elements 1c, 1d are laterally offset from each other with respect to the normal line of the contact lugs 7 a..10a for contacting the film capacitor elements 1c, 1 d. As a result, the contact lugs 7a, 8a of the first bent sheet metal part 4a and the contact lugs 9a, 10a of the second bent sheet metal part 5a or the contact lugs 7 a..10 a of different electrical polarities are at a relatively large distance from each other and thus are electrically well insulated from each other.

However, this is not the only conceivable possibility; in all other examples shown in fig. 14 to 34, the capacitor contacts 3 e..3 j of the film capacitor element 1 e..1 j are directly opposed to each other with respect to the normal line of the contact lugs 7 b..10d for contacting the film capacitor element 1 e..1 j. In other words, the two capacitor contacts 3 e..3j of the film capacitor element 1 e..1 j are located on the normal line of the contact lugs 7 b..10d. As a result, the force caused by the spring contact 3 e..3j of the film capacitor element 1 e..1 j inserted into the bus bar device 6 b..6 d is also located on the line of action, and therefore no torque acts on the film capacitor element 1 e..1 j inserted into the bus bar device 6 b..6 d. As a result, no special measures need to be implemented to prevent undesired rotation of the film capacitor element 1 e..1j.

In general, the film capacitor element 1 a..1j of the DC support capacitor 17 a..17 h may be implemented without a case, and may be wrapped with insulation (individually), as shown for the film capacitor elements 1 a..1 c, 1e, 1g, and 1 i. However, it is also conceivable that the film capacitor elements 1 a..1j of the DC support capacitors 17 a..17 h are each packaged in a separate case, as are the film capacitor elements 1d, 1f, 1h and 1 j. Finally, it is also conceivable that the film capacitor elements 1 a..1j of the DC support capacitors 17 a..17 h have a common DC support capacitor housing, in particular, they are encapsulated in this housing. The insulation of the film capacitor element 1 a..1j may in particular consist of or comprise a resin and may in particular be embodied liquid-impermeable.

Fig. 35 shows a first example of a power converter 18a, which power converter 18a is configured as an inverter and has a power section 19a, e.g. a power module connected to a DC support capacitor 17 i. The DC support capacitor 17i is configured to smooth the DC voltage of the DC voltage source, and the power section 19a is configured to generate an AC voltage from the smoothed DC voltage. Further, fig. 35 shows a Y capacitor 20, which forms or is part of an EMC filter, and is arranged between the DC support capacitor 17i and the input of the power section 19 a. The power section 19a has a plurality of controllable switches electrically connected to the DC support capacitor 17 i. The DC support capacitor 17i has electrical connections assigned to the bent sheet metal parts 4 a..4d, 5 a..5d. For example, the electrical connection of the DC link capacitor 17i may be implemented like the connection lugs 12 a..12 d, 13 a..13 d of the first bent sheet metal part 4 a..4 d and the second bent sheet metal part 5 a..5 d. Further, the power converter 18a includes a case 21 for the film capacitor element 1k and the Y capacitor 20. In particular, the film capacitor element 1k may be packaged together in the case 21. However, it goes without saying that they may also be individually wrapped by insulation and may in particular be individually encapsulated in a housing. Furthermore, it is conceivable that the film capacitor element 1k is both individually wrapped with insulation and jointly encapsulated in the case 21.

Fig. 36 shows another example of the power converter 18b also configured as an inverter. The plurality of controllable switches 22 of the power section 19b are clearly shown in fig. 36. For example, the controllable switch 22 may be implemented as a semiconductor switch, MOSFET, IGBT, or the like. Further, the power converter 18b includes a power converter case 23 to which the film capacitor element 1l of the dc support capacitor 17j is directly fixed. For example, the film capacitor element 1l can be directly fixed to the power converter housing 23 by means of an adhesive, in particular an adhesive having good thermal conductivity. In this way, the cooling of the DC support capacitor 17j can be significantly improved compared to other arrangements. This is especially the case if the power converter housing 23 is incorporated into a cooling circuit and the cooling medium flows, for example, through or around the housing. Furthermore, the heat transfer from the film capacitor element 1l to the power converter housing 23 is particularly good, since a separate housing for the film capacitor element 1l can be eliminated.

Note that the film capacitor element 1l directly fixed to the power converter case 23 at this time is not necessarily related to an inverter, but rather, this feature may be very commonly used for the power converters 18a, 18b.

Finally, fig. 37 shows a schematically illustrated electric vehicle 24 comprising an inverter 18 of the type disclosed above, a DC voltage source 25 (e.g. a battery or a fuel cell) connected thereto, and an electric motor 26 connected to the inverter 18, the electric motor 26 forming or being constituted by an electric drive of the electric vehicle 24. Specifically, a DC voltage source 25 is connected to the DC support capacitor 17 or the optional Y capacitor 20 of the inverter 18, and an electric motor 26 is connected to the power section 19 of the inverter 18. The electric motor 26 is mechanically coupled to wheels 28 of the electric vehicle 24 through axle shafts 27. The DC support capacitor 17 is configured to smooth a DC voltage obtained from a DC voltage source 25, and the power section 19 is configured to generate an AC voltage from the smoothed DC voltage and feed the AC voltage into the electric motor 26. In particular, the electric vehicle 24 may also have a cooling circuit into which the inverter 18 is incorporated. In particular, the liquid heat carrier can circulate in the cooling circuit.

In summary, it is emphasized that the scope of protection is determined by the patent claims. The specification and drawings, however, should be used to interpret the claims. The features contained in the drawings may be interchanged and combined as desired. In particular, it is also emphasized that the illustrated apparatus may in fact comprise more or less components than illustrated. In some cases, the illustrated devices or portions thereof may also be shown not to scale and/or in enlarged scale and/or in reduced scale.

Claims (10)

1. DC support capacitor (17, 17 a..17 j) for a power converter (18, 18a, 18 b), in particular an inverter, comprising:

a) A busbar arrangement (6 a..6 d) having a first bent sheet metal part (4 a..4 d) with a first sheet metal plane (A) and a second bent sheet metal part (5 a..5 d) electrically insulated therefrom with a second sheet metal plane (B) aligned parallel to the first sheet metal plane (A),

Wherein the second bent sheet metal part (5 a..5 d) and the first bent sheet metal part (4 a..4 d) are electrically insulated from each other by means of an insulating layer arranged between the sheet metal planes (A, B),

-Wherein the first bent sheet metal part (4 a..4 d) and the second bent sheet metal part (5 a..5 d) each comprise a plurality of contact lugs (7 a..10 d) arranged on the edges of the respective sheet metal and occurring as a result of bending from the sheet metal plane (A, B) or as a result of separating the respective sheet metal along a U-shaped separation line and bending from the sheet metal plane (A, B), and

-Wherein at least some of the contact lugs (7 a..8 d) of the first bent sheet metal part (4 a..4 d) are guided through the cutouts (11 a..11 d') in the second bent sheet metal part (5 a..5 d), and

B) A plurality of film capacitor elements (1 a..1 l), each having a wound metallized plastic film (2) and first and second capacitor contacts (3 a..3 j) electrically connected thereto,

Wherein the capacitor contacts (3 a..3j) are embodied as flat lug-type spring contacts,

-Wherein the first capacitor contacts (3 a..3 j) are each resiliently supported on a respective contact lug (7 a..8 d) of the first bent sheet metal part (4 a..4 d), the second capacitor contacts (3 e') are each resiliently supported on a respective contact lug (9 a..10 d) of the second bent sheet metal part (5 a..5 d), and

-Wherein the individual film capacitor elements (1 a..1 l) are electrically connected in parallel.

2. The DC support capacitor (17, 17 a..17 j) according to claim 1, characterized in that the first bent sheet metal part (4 a..4 d) and/or the second bent sheet metal part (5 a..5 d) is configured as a stamped bent sheet metal part, and that the cut-out (11 a..11 d') is shaped by a stamped part and/or by bending the contact lugs (7 a..10 d) from the sheet metal plane (A, B).

3. The DC support capacitor (17, 17 a..17 j) according to claim 1 or 2, characterized by a contact lug (7 a..10 d) for contacting the film capacitor element (1 a..1 l):

-aligned parallel to each other, and/or

-Aligned at right angles to the sheet metal plane (A, B).

4. A DC support capacitor (17, 17 a..17 j) according to any one of claims 1 to 3, characterized in that the capacitor contacts (3 a..3 j) of the film capacitor element (1 a..1 l) of the film capacitor elements (1 a..1 l) are directly opposite to each other with respect to the normal line of the contact lugs (7 a..10 d) for contacting the film capacitor element (1 a..1 l).

5. A DC support capacitor (17, 17 a..17 j) according to any one of claims 1 to 3, characterized in that the capacitor contacts of the film capacitor element (1 a..1 l) of the film capacitor elements (1 a..1 l) are laterally offset from each other with respect to the normal of the contact lugs (7 a..10 d) for contacting the film capacitor element (1 a..1 l).

6. The DC support capacitor (17, 17 a..17 j) according to any one of claims 1 to 5, characterized in that the film capacitor element (1 a..1 l):

Implemented without a housing and wrapped with insulation,

Each enclosed in a separate housing, or

-Having a common DC supporting capacitor housing (21), in particular a film capacitor element (1 a..1 l) enclosed therein.

7. The DC support capacitor (17, 17 a..17 j) according to any one of claims 1 to 6, characterized in that the insertion positions of the film capacitor elements (1 a..1 l) in the busbar arrangement (6 a..6 d) are arranged in rows and columns, wherein the contact lugs (7 a..10 d) directly adjacent to each other in rows are alternately part of the first curved sheet metal part (4 a..4 d) or the second curved sheet metal part (5 a..5 d), and wherein the contact lugs (7 a..10 d) directly below each other in columns are likewise alternately part of the first curved sheet metal part (4 a..4 d) or the second curved sheet metal part (5 a..5 d).

8. A power converter (18, 18a, 18 b) comprising a power converter housing (23) and a DC support capacitor (17, 17 a..17 j) according to any of claims 1 to 7, characterized in that the film capacitor element (1 a..1 i) is arranged directly on the power converter housing (23).

9. The power converter (18, 18a, 18 b) of claim 8, configured as an inverter, and having a power section (19, 19a, 19 b) with a plurality of controllable switches (22) electrically connected to the DC support capacitor (17, 17 a..17 j), wherein the DC support capacitor (17, 17 a..17 j) is provided for smoothing the DC voltage of the DC voltage source (25), and wherein the power section (19, 19a, 19 b) is provided for generating an AC voltage from the DC voltage smoothed by the DC support capacitor (17, 17 a..17 j).

10. An electric vehicle (24) characterized by an inverter according to claim 9, a DC voltage source (25) connected to the DC support capacitor (17, 17 a..17 j) and an electric drive (26) connected to the power section (19, 19a, 19 b), wherein the electric drive (26) is mechanically coupled to wheels (28) of the electric vehicle (24).