Compact power electronic system

Abstract

A compact power electronic system comprising a stacked arrangement of a capacitor device (1), a cooling device (2), a power switching device (3), and a control switching device (4), wherein the cooling device (2) has a first cooling contact surface (20) which is in thermal contact with the capacitor device (1) and a second cooling contact surface (22) opposite the first, which is in thermal contact with the power switching device (3), having a cuboid base shape, wherein the capacitor device (1) is arranged on a base (80) of a cuboid (8), wherein the capacitor device (1) forms a first partial housing (51) of the system or is arranged in a first partial housing (51) of the system, and wherein the capacitor device (1) comprises a plurality of capacitor elements (10) and an element connection device (12).wherein this is arranged between the first cooling contact surface (20) and the capacitor elements (10) and wherein the capacitor elements (10) are in thermal contact with the first cooling contact surface (20) by means of the element connection device (12).

Description

[0001] The invention describes a compact power electronic system with a stacked arrangement of a capacitor device, a cooling device, a power switching device and a control switching device.

[0002] DE 10 2019 134 650 A1 discloses a power electronic system comprising a housing, a cooling device, a power semiconductor module and a capacitor device, wherein a cooling section of a capacitor connection device is in thermally conductive contact with a cooling surface of the cooling device.

[0003] DE 10 2012 206 271 A1 discloses an arrangement comprising a cooling circuit, a plurality of connectable power semiconductor modules, and at least one capacitor arrangement, wherein a power semiconductor module has a power electronic switching device and a flow-through cooling device for cooling the switching device, which has a cooling volume, at least one cooling surface, and four connection points for a cooling fluid. The connection points are arranged in pairs on the main sides of the power semiconductor module. Furthermore, the power semiconductor modules are connected to one another with their main sides by directly or indirectly connecting corresponding connection points of successive power semiconductor modules.For this purpose, a capacitor assembly is arranged between at least two successive power semiconductor modules, which in turn is cooled directly or indirectly by means of the cooling circuit of the arrangement.

[0004] German patent application DE 10 2019 116 179 A1 discloses an inverter capacitor with an integrated internal cooling channel. An inverter system control module (ISC module) is provided. The ISC module includes a housing with an upper cavity, a lower cavity, a fluid inlet, a fluid outlet, and a partition extending in a plane between the fluid inlet and the fluid outlet. The inverter system further includes a power module secured in the upper cavity to define an upper fluid chamber together with the partition, and a capacitor assembly secured in the lower cavity to define a lower fluid chamber together with the partition.

[0005] DE 10 2012 215 787 A1 discloses a power electronic system comprising a multi-part housing, a plurality of power electronic circuit devices, a capacitor device and a liquid cooling device.The multi-part housing consists of three housing elements that are cuboid in their basic form, a central element, and an upper and a lower cover element arranged on opposite connection surfaces of the central element. The housing has an inlet connection and an outlet connection for a cooling liquid, and at least one upper cooling chamber is formed between the central element and the upper cover element, and at least two lower cooling chambers are formed between the central element and the lower cover element. Each cooling chamber has at least one cooling surface, and the cooling chambers are permeable to cooling liquid entering through the inlet connection and exiting at the outlet connection, thus forming the liquid cooling device.

[0006] DE 10 2022 203 036 A1 discloses a DC link capacitor for an electrical module, in particular for a power converter or inverter, comprising several capacitor elements. The DC link capacitor further comprises a one-piece housing with a cooling channel through which a heat transfer fluid can flow, and with a compartment separate from the cooling channel in which the capacitor elements are arranged and potted with a potting compound. The invention also relates to an electrical module, in particular for a power converter, with such a DC link capacitor, and to a vehicle with such an inverter.

[0007] In light of the aforementioned circumstances, the invention aims to optimize the arrangement and connection of the components.

[0008] This problem is solved according to the invention by a compact power electronic system with a stacked arrangement of at least four components, namely a capacitor assembly, a cooling assembly, a power switching assembly, and a control switching assembly, wherein the cooling assembly has a first cooling contact surface which is in thermal contact with the capacitor assembly and a second cooling contact surface opposite the first, which is in thermal contact with the power switching assembly, with a cuboid base shape, wherein the capacitor assembly is arranged on a base surface of a cuboid, wherein the capacitor assembly forms a first partial housing of the system or is arranged in a first partial housing of the system, and wherein the capacitor assembly has a plurality of capacitor elements and an element connection device on,wherein this is arranged between the first cooling contact surface and the capacitor elements and wherein the capacitor elements are in thermal contact with the first cooling contact surface by means of the element connection device.

[0009] It may also be preferred if each component is exclusively force-fitted to the component following it in a normal direction of the stacked arrangement.

[0010] It can be advantageous if the height ratio, viewed in the normal direction, between the height of the condenser assembly and the total height of the cooling assembly, the power switching assembly and the control switching assembly is between 2:1 and 1:1.

[0011] It can be advantageous if a section of a DC connection device is arranged laterally, preferably on a first longitudinal side of the cuboid, between the capacitor device and the power switching device.

[0012] It can also be advantageous if a DC voltage connection device is arranged on the first longitudinal side or on one of the first opposite second longitudinal sides of the cuboid.

[0013] It may also be preferred if an AC voltage connection device is arranged on the first or second longitudinal side of the cuboid.

[0014] Furthermore, it can be advantageous if a coolant connection device of the cooling device is arranged on the first or the second narrow side of the cuboid.

[0015] It can also be advantageous if the ratio of the length of a narrow side of the cuboid to the length of a long side of the cuboid is between 1:1.2 and 1:3, preferably between 1:1.3 and 1:2. It can also be advantageous if the ratio of the height of the cuboid to the length of its long side is between 1:1.2 and 1:3, preferably between 1:1.3 and 1:2. Here, individual protruding components, such as connecting elements, parts thereof, or plugs, are preferably not taken into account. The respective lengths are determined orthogonally to the normal direction.

[0016] It may be preferred if a resistance device, preferably designed as a discharge resistor of the capacitor device, is arranged laterally next to the power switching device and preferably in thermal contact with the second cooling contact surface.

[0017] It is also preferred if the power switching device is formed from a plurality of sub-switching devices.

[0018] It can be advantageous if the power switching device forms a multi-phase, preferably a three-phase bridge circuit, with a sub-switching device assigned to each phase.

[0019] It can also be advantageous if the power switching device forms a half-bridge circuit and the sub-switching devices are connected in parallel.

[0020] It may be preferred if a second sub-housing covers the cooling device, the power switching device, the control switching device and, if present, also the resistance device, and interacts with the first sub-housing.

[0021] The term power switching device should be understood as, by way of example, a power semiconductor module with or without a module housing or module sub-housing.

[0022] Of course, unless explicitly or per se excluded or contrary to the idea of ​​the invention, the features or groups of features mentioned in the singular, for example the power switching device or the control switching device, may be present multiple times in the system according to the invention.

[0023] It is understood that the various embodiments of the invention can be implemented individually or in any combination to achieve improvements. In particular, the features mentioned and explained above and below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention.

[0024] Further explanations of the invention, advantageous details and features, will become apparent from the following description of the invention contained in the Fig. 1 to 4 schematically illustrated embodiments of the invention, or of respective parts thereof. Fig. Figure 1 shows a schematic exploded view of a power electronic system according to the invention. Fig. Figures 2 to 4 show different three-dimensional views of a power electronic system according to the invention. Fig. Figure 4 shows a linear arrangement of a plurality of power electronic systems according to the invention.

[0025] Fig. Figure 1 shows a schematic exploded view of a power electronic system according to the invention. This compact system comprises, from bottom to top, a stacked arrangement in the normal direction N, consisting of a capacitor assembly 1, a cooling assembly 2, a power switching assembly 3, and a control switching assembly 4. The cooling assembly 2 has a first cooling contact surface 20 which is in thermal contact with the capacitor assembly 1. This thermal contact, without limiting generality, is directly connected to an element connection device 12, which forms a first part of a DC voltage connection device 6 between the capacitor assembly 1 and the power switching assembly 3.The individual capacitor elements 10 of the capacitor assembly 1 are then in indirect thermal contact with the first cooling contact surface 20 via the element connection assembly 12, again without restriction of generality.

[0026] The entire capacitor assembly 1 is arranged here in a first sub-housing 51 of the system.

[0027] A second cooling contact surface 22 of the cooling device 2, opposite the first, is in direct thermal contact with the power switching device 3. For this purpose, the power switching device 3, which here is designed as an unenclosed power semiconductor module, is arranged directly on the second cooling contact surface 22. Typically, a thermal paste can also be applied between the power switching device 3 and the second cooling contact surface 22.

[0028] The power switching device 3 is connected to the control switching device 4 by means of internal contact elements 30. This control switching device 4 is designed as a standard printed circuit board and serves to control the power switching device 3 and receives the associated control signal via a plug connection (not shown) to a higher-level control system, in particular a vehicle control system, if the power electronic system is part of a powertrain of an electric vehicle.

[0029] A second sub-housing 52, cooperating with the first sub-housing 51, covers the cooling device 2, the power switching device 3, and the control switching device 4. This second sub-housing 52 has coolant connections (not shown), as well as feedthroughs 510 for load connection elements 32 and plug connections for control signals (also not shown).

[0030] Fig. Figures 2 to 4 show different three-dimensional views of a power electronic system according to the invention with a first, but without the second, partial housing 51, 52, which together form a complete housing. Fig. 2 and Fig. Figure 4 shows a stacked arrangement of a capacitor assembly 1, a cooling assembly 2, a power switching assembly 3, and a control switching assembly 4, wherein the capacitor assembly 1 is enclosed by the first partial housing 51 and is not visible. This stacked arrangement corresponds to that shown in Figure 4. Fig. 1, schematically represented.

[0031] The configuration of the power switching device 3 shown here comprises a plurality, in this case three, sub-switching devices, each forming one phase of the three-phase load output of the power electronic system. The power switching device 3 thus forms a three-phase bridge circuit.

[0032] Also shown is a resistor 5 located laterally next to the power switching device 3 and in thermal contact with the second cooling contact surface 22. This resistor 5 is designed here as a discharge resistor for the capacitor device 1, which is required in the event of a fault.

[0033] Fig. Figure 3 schematically shows the cuboid basic form of the compact power electronic system as cuboid 8. Here, the capacitor arrangement is shown, cf. Fig. 1, arranged on a base 80 of the cuboid 8. This base 80 essentially also forms the base of the first partial housing 51. The ratio of the length of a narrow side 84,85 of the cuboid 8 to the length of a long side 82,83 of the cuboid 8 is 1:1.5 in this embodiment.

[0034] A section 60 of a DC voltage connection device 6 is arranged laterally on a first longitudinal side 82 of the cuboid 8, between the capacitor device 1 and the power switching device 3. A DC voltage connection device 62 for external supply of the system is arranged on the second longitudinal side 83 of the cuboid 8, opposite the first longitudinal side 82. An AC voltage connection device 62 for connection to an electric machine is also arranged on the second longitudinal side 83 of the cuboid 8.

[0035] Fig. Figure 5 shows a linear arrangement of a plurality of power electronic systems according to the invention, wherein the narrow sides 84, 85 of the respective cuboids 8, the basic form of the respective systems, face each other. The DC voltage connection devices 62 are shown in each case. Fig. 2 and Fig. 3, arranged on a second longitudinal side 83 of the cuboid 8. The AC voltage connection devices 62, cf. Fig. 4 are arranged on the same second longitudinal side 83 of the cuboid 8.

[0036] The respective coolant connection devices of the cooling unit 2, see below. Fig. 2, of the individual cuboids 8 are arranged on a narrow side 84,85 of the cuboid 8. The coolant connection devices of adjacent cuboids 8 can be connected to each other to form a chain of cooling devices 2.

[0037] Alternatively, it may be preferred if no electrical connection elements or coolant connection devices are arranged on the narrow sides 84, 85 of the respective cuboid 8, in order to be able to arrange the individual cuboids 8 as close together as possible.

Claims

[1] A compact power electronic system comprising a stacked arrangement of a capacitor device (1), a cooling device (2), a power switching device (3), and a control switching device (4), wherein the cooling device (2) has a first cooling contact surface (20) which is in thermal contact with the capacitor device (1) and a second cooling contact surface (22) opposite the first, which is in thermal contact with the power switching device (3), having a cuboid base shape, wherein the capacitor device (1) is arranged on a base (80) of a cuboid (8), wherein the capacitor device (1) forms a first partial housing (51) of the system or is arranged in a first partial housing (51) of the system, and wherein the capacitor device (1) comprises a plurality of capacitor elements (10) and an element connection device (12).wherein this is arranged between the first cooling contact surface (20) and the capacitor elements (10) and wherein the capacitor elements (10) are in thermal contact with the first cooling contact surface (20) by means of the element connection device (12). [2] Power electronic system according to one of the preceding claims, wherein each component, capacitor assembly (1), cooling assembly (2), power switching assembly (3) and control switching assembly (4), is exclusively force-fit connected to the component following in a normal direction (N) of the stacked arrangement. [3] Power electronic system according to one of the preceding claims, wherein the height ratio in the normal direction (N) between the height of the capacitor device (1) and the total height of the cooling device (2), the power switching device (3) and the control switching device (4) is between 2:1 and 1:

1. [4] Power electronic system according to one of the preceding claims, wherein a section of a DC connection device (6) is arranged laterally, preferably on a first longitudinal side (82, 83) of the cuboid (8) between the capacitor device (1) and the power switching device (3). [5] Power electronic system according to one of the preceding claims, wherein a DC voltage connection device (62) is arranged on the first longitudinal side (82) or on one of the first opposite second longitudinal side (83) of the cuboid (8). [6] Power electronic system according to one of the preceding claims, wherein an AC voltage connection device (32) is arranged on the first or the second longitudinal side (82, 83) of the cuboid (8). [7] Power electronic system according to one of the preceding claims, wherein a coolant connection device of the cooling device (2) is arranged on the first or the second narrow side (84, 85) of the cuboid (8). [8] Power electronic system according to one of the preceding claims, wherein the ratio of the length of a narrow side (84, 85) of the cuboid (8) to the length of the long side (82, 83) of the cuboid (8) is between 1:1.2 and 1:3, preferably between 1:1.3 and 1:

2. [9] Power electronic system according to claim one of the preceding claims, wherein the ratio of the height of the cuboid (8) to the length of the longitudinal side (82, 83) of the cuboid (8) is between 1:1.2 and 1:3, preferably between 1:1.3 and 1:

2. [10] Power electronic system according to one of the preceding claims, wherein a resistance device (5), preferably designed as a discharge resistor of the capacitor device (1), is arranged laterally next to the power switching device (3) and preferably in thermal contact with the second cooling contact surface (22). [11] Power electronic system according to one of the preceding claims, wherein the power switching device (3) is formed from a plurality of sub-switching devices. [12] Power electronic system according to claim 11, wherein the power switching device (3) forms a multi-phase, preferably a three-phase bridge circuit and a partial switching device is assigned to each phase. [13] Power electronic system according to claim 11, wherein the power switching device (3) forms a half-bridge circuit and the partial switching devices are connected in parallel. [14] Power electronic system according to one of the preceding claims, wherein a second partial housing (52) covers the cooling device (2), the power switching device (3), the control switching device (4) and, if present, also the resistance device (5) together and interacts with the first partial housing (51).

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