FORM 2
THE PATENT ACT 1970 (39 of 1970)
&
The Patents Rules, 2 0 03 COMPLETE SPECIFICATION (See Section 10, and rule 13)
1. TITLE OF INVENTION
MODULARLY CONSTRUCTED POWER CONVERTER ARRANGEMENT
2. APPLICANT(S)
a) Name : SEMIKRON ELEKTRONIK GMBH & CO. KG
b) Nationality : GERMAN Company
c) Address : SIGMUNDSTRASSE 200,
90431 NUERNBERG, GERMANY
3. PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed : -

The invention describes a power converter arrangement such as can be used on machine tools, for example, for the rotational-speed-regulated drive of electric motors used therein. Generally, a large number of different types of power converters can be constructed with the modularly constructed power converter arrangement according to the invention. They include, in particular, rectifiers, inverters and frequency converters. Moreover, the number of phases of the respective power converters is not absolute. Particularly preferably, these power converter arrangements are used for powers of the orders of magnitude of 10 kW and 100 kW.
Power converter arrangements generally known for this power class include, on the one hand, completely prefabricated power converter arrangements or, on the other hand, individual solutions specifically tailored to the task.
The invention is based on the object of presenting a power converter arrangement which is constructed modularly and can therefore easily be adapted to the required function and/or power, without a large number of different basic elements being required.
This object is achieved according to the invention by means of a power converter arrangement comprising the features of Claim 1. Preferred embodiments are described in the dependent claims.
The starting point for the invention is formed by a power converter module comprising a housing open at both end sides, and also two end-side elements, between which at least one of said power converter modules is arranged. In this case, the at least one power converter module has, as part of the cooling device ot the power converter arrangement, a heat sink, through which flow can take place from the first to the second end-side element of the power converter module.

At least one power semiconductor module is arranged in a circuit- and power-conforming fashion on said heat sink. In this case, the arrangement can consist, for example, of a plurality of power semiconductor modules of identical type which form half-bridges and which, connected accordingly, form a three-phase inverter.
The at least one power semiconductor module is connected to a control device, which is likewise arranged in the interior of the housing, and also to a capacitor device. Said capacitor device preferably consists of two capacitor banks, which are arranged in a mirror-inverted fashion with respect to one another in each case on a dedicated printed circuit board. Said capacitor device is connected to the power semiconductor modules in a circuit-conforming fashion. It is furthermore preferred to arrange, from an end-side consideration, one capacitor bank alongside the heat sink, and the further capacitor bank alongside the at least one power semiconductor module, thus resulting in a very compact construction overall. In this case, it is likewise possible and expedient from a circuitry standpoint to arrange the control device directly above the at least one power semiconductor module.
The housing open at the end sides can be connected, at its respective end side, to an end-side element, or a further power converter module. For this purpose, the housing is preferably embodied as a U-shaped base housing with a matched cover. For connection to an end-side element, or to a further housing, the U-shaped base housing has connection means of identical type at the end sides at the side walls.
This gives rise to the modularly constructed power converter arrangement comprising a first end-side element and one or a plurality of preferably different power converter modules. Said power converter modules differ in terms of their internal circuitry, whereby rectifiers, or inverters, for example, are formed, and alternatively, or simultaneously, also in terms of the length of the respective housing. The length of the housing preferably scales on account of the required

cooling capacity or on account of the required capacitance of the capacitor device. In this case, it is preferred if a limited selection of housings having different lengths is provided.
Furthermore, two end-side elements are provided, each having dedicated parts of the cooling device of the power converter arrangement. For this purpose, a first end-side element has at least one fan for the cooling device embodied as an air cooling device. The second end-side element has, in alignment with said at least one fan, a plurality of cutouts acting as air passages. Consequently, cooling air can flow through the power converter arrangement from end side to end side by means of fans, and cool the power semiconductor modules by means of the heat sinks.
FigParticularly preferred developments of the invention are mentioned in the respective description of the exemplary embodiments. The inventive solution is additionally explained in further detail on the basis of the exemplary embodiments and figures l to 4.
ure 1 shows a first configuration of the power converter arrangement according to the invention in a three-dimensional exploded view.
Figure 2 shows a second configuration of the power converter arrangement according to the invention in a three-dimensional view.
Figure 3 shows a power converter arrangement according to the invention in a plan view of an end-side element.
Figure 4 shows a power converter arrangement according to the invention in a lateral plan view.

Figure 1 shows a first configuration of the power converter arrangement (1) according to the invention in a three-dimensional exploded view. The illustration shows a first end-side element (10) having cutouts (16) for the general cooling of the power converter arrangement, specifically of the control circuit. Furthermore, this end-side element has two fans (12) and an electrical connection device (14). In this case, without restricting the generality, this connection device has three screw connection devices for the external connection of, for example, a three-phase AC motor.
The fans (12) serve for feeding cooling air to the interior of the power converter arrangement (1). The latter is furthermore embodied here with a power converter module (30) following said first end-side element (10) and with a second end-side element (20) wherein the latter has a plurality of cutouts (22) aligned with the position of the fans in the first end-side element (10).
The power converter module (30) illustrated has a heat sink (32) as part of the cooling device of the power converter arrangement (1), which is formed moreover by the fans (12) of the first end-side element and the air passages (22) of the second end-side element. In this case, the cooling ribs (320) of the heat sink (32) are arranged in such a way that the cooling air can flow through from the first end-side element (10) to the second end-side element (20). For this purpose, the heat sink (32) is arranged in the housing (300) of the power converter module (30) in alignment with the fans (12) and the air passages (22).
The housing (300) of the power converter module (30) is open at the end sides and moreover consists of a U-shaped base housing (302) having a base area (310), and of a matched cover (304). In this case, the base housing (302) has fixing elements for fixing the components (32, 34, 38) of the power converter circuit, and connection elements (308) for respective end-side connection to an end-side element (10, 20), or

to a further base housing (300) of a further power converter module (30). Said connection elements (308) are embodied as lugs having cutouts which engage in areas or lugs of the end-side element (10, 20), or further base housing (300) to be connected and are fixed there by means of screw or rivet connections.
The end-side elements (10, 20) thus form with the housing (300) of the power converter module (30) the overall housing of the power converter arrangement (1), which are preferably also arranged on two angular rails at their lower outer edges. By means of said angular rails (2), the power converter arrangement (1) can be connected to a larger unit, for example to a switchgear cabinet, in a simple manner.
In the base housing (300) of the power converter module (30), the heat sink (32) is arranged on the base area (310) in such a way that, from the viewing direction of the end-side elements (10, 20), laterally a region also remains free for a capacitor device (38). The at least one power semiconductor module (34) is assigned to said capacitor unit (38) and arranged on the heat sink (32). The type and interconnection of this one or plurality of power semiconductor modules (34) determine the functionality of the respective power converter module (30). For the known and preferred three-phase operation, it is advantageous to arrange three power semiconductor modules (34) of identical type and to connect them to one another and to the capacitor device (38) in a circuit-conforming fashion by means of a connection device (340). On said connection device (340), in this case preferably directly the control device (36) for driving the power semiconductor modules (34) is arranged and connected in a circuit-conforming fashion and with short line paths.
Said capacitor device (38) itself consists of two capacitor banks (380 a/b). The first capacitor bank (380 a) is arranged alongside the heat sink (32) in the base housing (300). The individual capacitors (382 a) are connected to one another by means of a printed circuit board (384 a). Furthermore, said printed circuit board (384 a) is

connected integrally or in a multipartite fashion to the connection device (340) or directly to the power semiconductor modules (34) in a low-inductance manner. The second capacitor bank (380 b) is advantageously arranged in a mirror-inverted manner with respect to the first capacitor bank, in which case the respective printed circuit boards (384 a/b) then face one another.
Above the power semiconductor modules (34) and their control device (36) for driving the power semiconductor components of the power semiconductor modules, it is furthermore possible to arrange a customer-specific additional circuit board (360), which imparts additional functionality to the power converter module.
Figure 2 shows a second configuration of the power converter arrangement (1) according to the invention in a three-dimensional view. For this purpose, two power converter modules (30 a/b) having different lengths are jointly connected to a first and a second end-side element (10,20). The connection means (308) described above are used for this purpose.
The different lengths of the two power converter modules (30 a/b) result here from the different power and hence the different cooling requirement of the respectively incorporated power semiconductor modules that are connected to form different circuits. By virtue of these different lengths of the respective power converter modules (30 a/b), the latter are particularly advantageously adapted to the required power, as a result of which only that structural volume which is actually necessary from a circuitry standpoint is required. It is likewise advantageous for the modular construction to provide a plurality, but a limited number, of housings of different lengths, in particular since a doubled power can be obtained in a simple manner by combination of two identical power converter modules (30 a/b).

In this case, however, it can also be advantageous to distribute its functional units, such as a three-phase bridge circuit, for example, between two power converter modules (30). This can be effected by virtue of the fact that two identical power converter modules (30) each comprise two power semiconductor modules, three being used for said three-phase bridge circuit and the fourth being used for a further functionality. Consequently, the advantages of the modular construction can be increased even further.
Figure 3 shows a power converter arrangement (1) according to the invention in a plan view of an end-side element (10) such as has already been illustrated in Figures 1 and 2. Figure 3a illustrates cutouts (16) embodied as cooling air inlets, fans (12) and connection devices (14), while Figure 3b illustrates a virtual view into the interior, which schematically shows the position of the heat sink (32), of the two capacitor banks (380 a/b) of the capacitor device (38), and the three power semiconductor modules (34).
Figure 4 shows a power converter arrangement (1) according to the invention such as is also illustrated in Figure 2, in a lateral plan view. A virtual view into the interior of the two power converter modules (30 a/b) is likewise indicated here. The illustration schematically shows here, from a lateral view, the position of the two heat sinks (32) with the power semiconductor modules (34) and the position of the two capacitor banks (380 a/b) of the capacitor device (38).
Adjacent power converter modules (30 a/b) are advantageously connected to one another by means of cable connections (not illustrated) arranged in a closely adjacent fashion. The connection to the connection devices (14) of the end-side elements (10, 20) is formed in just the same way.

What is advantageous about the power converter arrangement (1) according to the invention is that, by virtue of the modular construction thereof with a small number of housings (300) for power converter modules (30), with different lengths, with at the same time flexible and nevertheless compact internal configuration, it is possible to form in each case a power converter arrangement with optimum power in conjunction with desired functionality.

WE CLAIM:
1. Modularly constructed power converter arrangement (1) comprising a first
(10) and a second (20) end-side element and at least one power converter
module (30) arranged therebetween,
wherein the first end-side element (10) has at least one fan (12) of an air cooling device, the second end-side element (20) has in alignment with said fan (12) a plurality of cutouts (22) acting as air passages, and at least one end-side element (10, 20) has an electrical connection device (14),wherein the at least one power converter module (30) has, as part of the cooling device, a heat sink (32), through which flow can take place from the first to the second end-side element and on which is arranged in a circuit- and power-conforming fashion at least one power semiconductor module (34) connected to a control device (36) and to a capacitor device (38) and wherein the at least one power converter module (30) has a housing (300), which is open at the end sides and which can be connected in each case at the end sides to an end-side element (10, 20) or a further power converter module (30).
2. Power converter arrangement according to Claim 1,
wherein the capacitor device (38) consists of two capacitor banks (380 a/b) arranged in a mirror-inverted fashion with respect to one another.
3. Power converter arrangement according to claim 2,
wherein the capacitors (382 a/b) of a capacitor bank (380 a/b) are in each case arranged on an assigned printed circuit board (384 a/b) and connected in a circuit-conforming manner by means of the latter.

4. Power converter arrangement according to Claim 2,
wherein one capacitor bank (380a), is arranged, from an end-side consideration, laterally alongside the heat sink (32) and the further capacitor bank (380 b) is arranged alongside the power semiconductor module (34).
5. Power converter arrangement according to Claim 1,
wherein a functional unit is distributed between two power converter modules (30 a/b).
6. Power converter arrangement according to Claim 1,
wherein the housing (300) of each power converter module (30) consists of a U-shaped base housing (302) and a matched cover (304).
7. Power converter arrangement according to Claim 1,
wherein the housing (300) has a length that is dependent on the necessary cooling capacity of the power semiconductor modules (34) or the capacitance of the capacitor device (38), and said length is thus different in a plurality of power converter modules (30).
8. Power converter arrangement according to Claim 6,
wherein the U-shaped base housing (300) has at the end sides at the side walls (306) connection means (308) of identical type for respective connection to an end-side element (10,20) or a further U-shaped base housing (300).
9. Power converter arrangement according to Claim 6,
wherein the heat sink (32) of a power converter module (30) is arranged on the base area (310) of the base housing (300) and the cooling ribs (320) extend from end side to end side.

10. Power converter arrangement according to Claim 1,
wherein the control device (36) is arranged directly above the power semiconductor modules (34).