Capacitor, system with multiple capacitors and motor vehicle

Abstract

A capacitor (100) comprising several electrically conductive capacitor layers wound around a winding center and a cooling channel (103), wherein the cooling channel (103) is arranged between the capacitor layers, wherein the cooling channel (103) is electrically conductive, wherein the capacitor (100) has a first terminal and a second terminal at a first end, wherein the first terminal and the second terminal are each configured for an electrical connection with at least one other electronic component, wherein the capacitor (100) has a second end which is arranged opposite the first end, and wherein the cooling channel electrically connects the second end to the second terminal, characterized in that the cooling channel (103) has a first opening and a second opening which are arranged opposite each other.wherein the cooling channel (103) can be connected via the first opening to a first cooling medium line and via the second opening to a second cooling medium line, so that a cooling medium can flow from the first cooling medium line through the cooling channel (103) into the second cooling medium line.

Description

[0001] The present invention relates to a capacitor according to the preamble of claim 1.

[0002] Film capacitors are known from the prior art, in which insulating plastic films are used as the dielectric. For this purpose, the plastics are drawn into extremely thin films using special processes, provided with the electrodes, and then wound as a coil or assembled from individual layers to form a capacitor.

[0003] As with many electronic components, capacitors generate heat during operation. This is especially true when the capacitors are used as power electronic components, for example in an inverter or a DC / DC converter. The demand for ever higher power outputs and increasingly compact designs means that heat must be dissipated particularly efficiently to also achieve a long capacitor lifespan.

[0004] From CH 368 236 A a capacitor is known in which cooling channels are arranged between the capacitor layers.

[0005] From JP 2008 - 311 253 A a capacitor with an electrically conductive cooling channel is known.

[0006] A capacitor according to the preamble of claim 1 is known from EP 3 477 669 A1.

[0007] AT 525 286 A4 reveals further state of the art.

[0008] In contrast, the present invention aims to enable a particularly compact design for a capacitor. Furthermore, it seeks to create a motor vehicle equipped with such a capacitor.

[0009] This problem is solved by a capacitor according to claim 1, a system according to claim 3, and a motor vehicle according to claim 5. Embodiments of the invention are specified in the dependent claims.

[0010] The capacitor according to claim 1 comprises several electrically conductive capacitor layers wound around a winding center. For the purposes of this description, the term "winding center" is to be understood as a geometric term and not as a component. The winding center defines an area around which the capacitor layers are wound. The capacitor layers may, for example, form a single continuous winding. The capacitor may, for example, be a film capacitor. The capacitor also comprises a cooling channel. For the purposes of this description, a cooling channel is understood to be a component designed to guide a fluid from a first opening to a second opening with no loss or with extremely low loss. The cooling channel is arranged between the capacitor layers. For example, the cooling channel may be located inside or outside the winding center.

[0011] The cooling channel is electrically conductive. For example, the cooling channel may have a wall made of metal. Preferably, the cooling channel has a conductivity of more than 10 Ω. 6 S / m. For example, the cooling channel can include copper and / or aluminum. It is also possible that the cooling channel is made of copper and / or aluminum.

[0012] The cooling channel can therefore fulfill two functions. A cooling medium can flow through it to dissipate heat from the condenser. Additionally, the cooling channel can be used for potential and / or current conduction.

[0013] This can also reduce the inductance of the capacitor, making the capacitor more suitable as a fast-switching power element, for example for operation with fast-switching power semiconductors.

[0014] According to one embodiment of the invention, the capacitor can have a first terminal and a second terminal at a first end. The first terminal and the second terminal can each be configured for an electrical connection with at least one other electronic component. The capacitor can have a second end that is arranged opposite the first end. The cooling channel can electrically connect the second end to the second terminal. Thus, the electrical potential present at the second end of the capacitor can be conducted via the electrically conductive cooling channel to the second terminal located at the first end. The advantage is that the capacitor only needs to be electrically contacted at its first end. For example, the first terminal can be electrically insulated from the second terminal by an insulating layer.It should be noted that, in this description, the first end of the capacitor refers specifically to an end region that includes both the first and second terminals and the insulating layer. The end region can therefore be three-dimensional and include an outward-facing end surface that forms the termination of the capacitor.

[0015] According to one embodiment of the invention, the cooling channel can be designed as a tube. In particular, the tube can be round. The tube can, for example, have a circular or elliptical cross-section. The cooling channel can be arranged in the winding center and form a core onto which the condenser layers are wound. This can particularly mean that, during the manufacture of the condenser, the condenser layers are wound directly onto the cooling channel. The cooling channel can thus also fulfill a third function, namely that of the core.

[0016] The cooling channel has a first opening and a second opening, positioned opposite each other. The cooling channel can be connected to a first cooling medium line via the first opening and to a second cooling medium line via the second opening, allowing a cooling medium to flow from the first cooling medium line through the cooling channel into the second cooling medium line. Thus, during operation of the condenser, the cooling medium flows from the first cooling medium line through the cooling channel into the second cooling medium line. For the purposes of this description, a cooling medium is understood to be, in particular, a fluid designed to absorb and dissipate heat generated by the condenser. The cooling medium can, for example, be heated within the condenser and transfer its heat outside the condenser to another medium, particularly via a heat exchanger. The cooling medium can, for example, be electrically insulating.

[0017] The system according to claim 3 comprises several capacitors according to an embodiment of the invention and a busbar. The capacitors are electrically connected to each other via the busbar. The capacitors arranged in this way can each also be individually referred to as a capacitor winding. The first cooling medium line is arranged on the busbar and runs parallel to the busbar. For example, the busbar can form a wall of the cooling medium line.

[0018] The electrical connection to the busbar is particularly advantageous for a system that is especially easy to install.

[0019] It is particularly possible that the system includes an additional busbar via which the capacitors are electrically connected to each other and to which the second cooling medium line is attached. This additional busbar could, for example, form a wall of the second cooling medium line.

[0020] According to one embodiment of the invention, the first cooling medium line can have several projections that increase the contact area of ​​the first cooling medium line in contact with the system's environment. The same can be provided accordingly for the second cooling medium line. These projections improve heat dissipation from the cooling medium to the environment. The projections can, for example, be rib-shaped. If the busbar forms a wall of the first cooling medium line, the busbar can, for example, have the projections.

[0021] It is possible for a system to comprise multiple capacitors, each with several electrically conductive capacitor layers wound around a central winding point. The system may include multiple cooling channels, each positioned between the capacitors. The capacitors may, for example, exhibit features described earlier in this description.

[0022] The arrangement of the cooling channels between the condensers is particularly advantageous for a space-saving arrangement and efficient heat dissipation.

[0023] The cooling channels can be arranged in spaces between the condensers, defined by adjacent condensers. These spaces can, for example, be defined solely by the adjacent condensers. In particular, it is possible for the condensers to be arranged so that they are adjacent to one another. For instance, one condenser can be adjacent to at least four or even six other condensers. The spaces can then be created by the shape of the condensers, such as a circular or elliptical cross-section, or by their flat winding configuration.

[0024] The cooling channels are electrically conductive.

[0025] The motor vehicle according to claim 5 comprises a system or a capacitor according to an embodiment of the invention. For example, the system or the capacitor can be part of an inverter or a DC / DC converter of the motor vehicle.

[0026] Further features and advantages of the present invention will become clear with reference to the following description of preferred embodiments and the accompanying figures. The same reference numerals are used for identical or similar features and for features with identical or similar functions. Fig. 1 a schematic sectional view of a capacitor according to an embodiment of the invention; Fig. 2 a schematic sectional view of a system according to an embodiment of the invention with capacitors arranged side by side; Fig. 3 a schematic sectional view of a system according to an embodiment of the invention with capacitors arranged one above the other and next to each other; Fig. 4 a schematic sectional view of two capacitors arranged one above the other; Fig. 5 a cross-sectional view through a system with multiple capacitors and cooling channels arranged in free spaces defined by the capacitors; Fig. 6 a cross-sectional view through a system with multiple capacitors and cooling channels arranged in free spaces defined by the capacitors; Fig. 7 a cross-sectional view through a system with multiple capacitors with cooling channels as winding cores; Fig. 8 a cross-sectional view through a system with multiple capacitors with cooling channels as winding cores; Fig. 9 a cross-sectional view through a system with multiple condensers and cooling channels arranged in free spaces between the condensers; and Fig. 10 a cross-sectional view through a system with multiple condensers and cooling channels arranged in free spaces between the condensers.

[0027] The capacitor 100 in Fig. 1 comprises several capacitor layers formed as a winding 101. The winding 101 is coated at two opposite ends with a Schoop layer 102. This can be, for example, a metal layer that has been vapor-deposited. It serves for the electrical contact of the winding 101. The winding is wound around two cooling channels 103. The cooling channels 103 are electrically conductive.

[0028] Furthermore, the capacitor 100 comprises a first conductor rail 104, on which a first cooling medium line is arranged. In the figures, only one wall of the first cooling medium line is shown, which is formed section by a first sheet 105 and a second conductor rail 107. The first conductor rail 104 serves for potential guidance. The capacitor 100 can be electrically connected via the first conductor rail 104 to, for example, several other, preferably identical, capacitors 100. The capacitor 100 also comprises a second cooling medium line, the wall of which is formed at least section by a second sheet 108. The first cooling medium line is arranged at a first end of the capacitor 100, which is opposite a second end of the capacitor 100, with the second cooling medium line being arranged at the second end.

[0029] The first cooling medium line and the second cooling medium line are connected to each other via the cooling channels 103, so that heat generated within the winding 101 can be reliably and efficiently dissipated into the first or second cooling medium line by a fluid flowing through the cooling channels 103.

[0030] Due to the electrical conductivity of the cooling channels 103, an electrical potential can be conducted from the second end of the capacitor 100 to the second conductor rail 107 at the first end of the capacitor 100 through the winding 101. The capacitor 100 can also be electrically connected to several other identical capacitors 100 via the second conductor rail 107. The second conductor rail 107 thus also serves for potential transfer. Due to the different potentials of the first conductor rail 104 and the second conductor rail 107, the two conductor rails 104 and 107 are electrically isolated from each other by means of an insulating layer 106.

[0031] During operation, the cooling medium can flow, for example, from the first cooling medium line through the cooling channels 103 to the second cooling medium line or in the opposite direction.

[0032] The cooling channels 103 thus fulfill three functions in one component. First, they serve as potential guides, since they are electrically conductive. Second, they serve as the winding core on which the winding 101 is wound. Third, they reliably and efficiently dissipate heat from the winding center of the capacitor 100.

[0033] The in Fig. The system shown in Figure 2 comprises several capacitors, each containing a winding 101 wound around a cooling channel 103. In contrast to the system shown in Figure 2, the capacitors are arranged in a different configuration. Fig. In the capacitor 100 shown, the second current conductor 107 is arranged at the second end of the capacitors 100.

[0034] Much more important in the system is in Fig. 2. However, the first and second cooling medium lines each have several projections 200 that increase the surface area of ​​the respective cooling medium line, so that the heat absorbed by the condenser can be dissipated more effectively to the environment. In the Fig. 2 and Fig. 3 A wall of the respective cooling medium line is formed by one of the conductor rails 104 and 107, so that the projections 200 are arranged on the conductor rails 104 and 107.

[0035] The in Fig. The system shown in Figure 3 comprises several capacitors 100 arranged one above the other and side by side. The capacitors arranged side by side are connected to each other via busbars 104 and 107. The busbars 104 and 107 are – similar to the system shown in Figure 3 – connected to the capacitors arranged side by side. Fig. The capacitor 100 shown in Figure 1 is arranged at the same end as the other capacitors 100. This is possible because the cooling channels 103 are electrically conductive.

[0036] It should also be noted that the lower capacitors have their two conductor rails 104 and 107 at their upper end, while the upper capacitors have their conductor rails 104 and 107 at their lower end. This results in all conductor rails 104 and 107 being located between the upper and lower capacitors, thus achieving a particularly compact design.

[0037] In Fig. Figure 4 shows two capacitors 100 arranged one above the other, which are made of capacitors 100. Fig. 3. The first end of the lower capacitor 100 faces the first end of the upper capacitor 100, so that - as in Fig. 3 - The busbars 104 and 107 of both the upper capacitor 100 and the lower capacitor 100 are arranged centrally between the upper capacitor 100 and the lower capacitor 100. This is possible due to the electrical conductivity of the cooling channels 103, which are used for potential transfer from the second end to the respective busbar 107 at the first end.

[0038] In Fig. Figure 5 shows several flat-wound capacitors 100. Their cross-section has a shape with two parallel straight sections, each connected at its end by a circular arc segment. This shape creates spaces between the capacitors 100 in which cooling channels 103 are arranged, allowing these spaces to dissipate heat. This is particularly advantageous because the spaces could not be filled or reduced by increasing the size of the windings 101 of the capacitors 100 by adding more layers around the winding center. This is not possible because adjacent capacitors 100 are already in close proximity. Thus, the available installation space is used very efficiently.

[0039] The capacitors 100 in Fig. Six had a circular cross-sectional area. Similar to the capacitors 100 made of Fig. There are 100 free spaces between the condensers that cannot be filled by increasing the size of the condensers. The cooling channels 103 are arranged in these free spaces. Thus, the installation space is used particularly efficiently in this system as well.

[0040] In the Fig. 7 and Fig. 8 are capacitors 100 with cross-sectional shapes as in the Fig. 5 and Fig. Figure 6 shows the windings being wound onto a cooling channel 103. In these cases, the cooling channel can fulfill three functions: electrical potential guidance, cooling, and winding core.

[0041] In Fig. Figure 9 shows several capacitors 100, between which cooling channels 103 are arranged. Each cooling channel 103 is connected to several capacitors 100 simultaneously, thus requiring very few components for assembly.

[0042] In Fig.Figure 10 shows several capacitors 100, between which cooling channels 103 are arranged. Here, too, a cooling channel 103 is connected to several capacitors 100 simultaneously. Due to the circular shape of the capacitors 100, the cooling channels each run in a zigzag pattern.

Claims

[1] Capacitor (100) comprising several electrically conductive capacitor layers wound around a winding center and a cooling channel (103), wherein the cooling channel (103) is arranged between the capacitor layers, wherein the cooling channel (103) is electrically conductive, wherein the capacitor (100) has a first terminal and a second terminal at a first end, wherein the first terminal and the second terminal are each configured for an electrical connection with at least one other electronic component, wherein the capacitor (100) has a second end arranged opposite the first end, and wherein the cooling channel electrically connects the second end to the second terminal, characterized by, that the cooling channel (103) has a first opening and a second opening which are arranged opposite each other, wherein the cooling channel (103) can be connected to a first cooling medium line via the first opening and to a second cooling medium line via the second opening, so that a cooling medium can flow from the first cooling medium line through the cooling channel (103) into the second cooling medium line. [2] Capacitor (100) according to claim 1, characterized by , that the cooling channel (103) is designed as a tube, wherein the cooling channel (103) is arranged in the winding center and forms a winding core on which the condenser layers are wound. [3] System comprising several capacitors (100) according to claim 1 or 2 and a conductor rail (104; 107), wherein the capacitors (100) are electrically connected to each other via the conductor rail (104; 107), and wherein the first cooling medium line is arranged on the conductor rail (104; 107) and runs parallel to the conductor rail (104; 107). [4] System according to claim 3, characterized by , that the first cooling medium line has several projections (200) which increase the contact area of ​​the first cooling medium line that is connected to an environment of the system. [5] Motor vehicle comprising a system according to claim 3 or 4 or a capacitor (100) according to claim 1 or 2.

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