Coil Assembly
The coil assembly design with thermal conduction structures on the circuit support improves heat dissipation, addressing heat management challenges in high-voltage and high-current applications, thereby increasing power density and reducing structural space.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- ROBERT BOSCH GMBH
- Filing Date
- 2024-04-02
- Publication Date
- 2026-05-12
AI Technical Summary
Existing coil assemblies face challenges in effectively dissipating heat, leading to limitations in power density and structural space requirements, particularly in high-voltage and high-current applications.
A coil assembly design featuring a circuit support with thermal conduction structures that facilitate cooling paths for individual windings, including thermal conduction structures on both sides of the magnetic core and the circuit support, allowing for improved heat dissipation and reduced structural space.
Enhances heat dissipation capacity, enabling higher power density and reduced structural space requirements while maintaining efficient electrical connectivity.
Smart Images
Figure 2026514563000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a coil assembly including a circuit support and at least one electric coil, wherein the winding of the electric coil is wound around a magnetic core surrounding at least one inner opening by at least two turns and penetrates at least one inner opening.
Background Art
[0002] From German Patent Application Publication No. 102016\ 210746, an inductive element is known which has a toroidal core made of a soft magnetic material that annularly surrounds an inner opening, and at least two conductive conductor path pieces each having two conductor path end regions that penetrate the inner opening and do not completely surround the toroidal core. These conductor path end regions are parallel to each other and are guided away from the toroidal core perpendicular to the toroidal core, forming at least one winding and being electrically connected to each other. These conductor path end regions are axially arranged outside the inner opening and outside the virtual extension of the inner opening. This inductive element is arranged on an electrically insulating support plate having a plurality of holes, and this support plate has a conductive structure at least around the holes. The conductor path end sections of the conductor path pieces are guided through the holes and are electrically connected to each other via the conductive structure so as to form at least one winding.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] Disclosure of the Invention A coil assembly having the features of independent claim 1 has the advantage that cooling of at least one electrical coil is performed via a circuit support. Here, a cooling path for each individual winding of at least one electrical coil can be made through the circuit support to at least one cooling element located on the surface of the circuit support opposite to the coil. This at least one cooling element may be located on the surface of the circuit support opposite to the coil, preferably inside the area covered by at least one electrical coil. Additionally or alternatively, the at least one cooling element may be located on the surface of the circuit support opposite to the coil, outside the area covered by at least one electrical coil. In embodiments of the present invention, further additional cooling of at least one coil is possible on the side of at least one coil opposite to the circuit support, where further cooling elements can be mounted on the winding of at least one coil.
[0005] The electrical contact connections of the individual windings of at least one coil on the circuit support can, in an advantageous manner, enable improved heat dissipation through individual cooling paths, thereby enabling a greater dissipation capacity of at least one coil. This can enable higher power density or packing density, and consequently, a reduced structural space requirement. Furthermore, the design of at least one coil, or the expandability of the heat conduction structure of the circuit support, and consequently the expandability of the cooling paths for each of the individual windings, can be achieved with comparable space requirements. [Means for solving the problem]
[0006] Embodiments of the present invention provide a coil assembly comprising a circuit support, at least one electric coil having a winding which is wound by at least two windings around a magnetic core surrounding at least one inner opening and which penetrates at least one inner opening, and at least one cooling assembly. The at least two windings each have one conductive conductor path piece having two end pieces, which are each inserted into and in contact with an electrical through-contact connection provided within the circuit support. Herein, the cooling assembly has at least two first thermal conduction structures in the region of the magnetic core on the surface of the circuit support facing the coil, and the at least two first thermal conduction structures are thermally coupled to at least two corresponding second thermal conduction structures on the surface of the circuit support opposite to the coil via at least one thermal through-contact connection. At least two first heat conduction structures are spaced apart from each other and each connected to at least one contact connection of a plurality of electrical through-contact connections, and at least two second heat conduction structures are spaced apart from each other and thermally coupled to at least one cooling element located on the surface of the circuit support opposite to the coil, thereby forming one cooling path between the end pieces of the at least two windings that are in contact with the corresponding electrical through-contact connections and the at least one cooling element.
[0007] In this specification, a magnetic core can be understood to mean a circular, elliptical, or rectangular toroidal core having or not having a central web, preferably manufactured from a soft magnetic material.
[0008] Embodiments of the coil assembly according to the present invention can be used, for example, as choke coils for interference suppression in electrical and electronic circuits in high-voltage or high-current applications. Such interference suppression choke coils can be suitably used to suppress interference currents that occur in the same direction in both the forward and return paths. Such current-compensated choke coils can also be called common-mode choke coils and have multiple identical windings through which the operating current flows in opposite directions. Thus, in an ideal perfectly symmetric winding with the same number of turns and the same wiring, the magnetic fields of the individual windings within the magnetic core of the choke coil cancel each other out, and therefore the choke coil has low inductance with respect to the operating current, but the inductance of the choke coil becomes significantly higher with respect to interference currents that occur in the same direction.
[0009] In this specification, an electrical through-contact connection can be understood as a continuous opening in a circuit support having a conductive wall or sleeve. Individual end pieces of a winding can be inserted into such an electrical through-contact connection and soldered to the wall or sleeve of the through-contact connection and the thermal conduction structure of the circuit support during the subsequent soldering process. The cross-sections of the conductive wall or sleeve and the end pieces of the individual windings can preferably be selected such that an annular gap is formed between the inserted end piece and the conductive wall or sleeve of the electrical through-contact connection, this annular gap facilitating the insertion of the end piece and allowing solder to penetrate during soldering. Furthermore, the thermal conduction structure has a predetermined minimum width in the area of the electrical through-contact connection. The thermal conduction structures on the surface of the circuit support facing the coil and the surface opposite the coil may be made of a material with good thermal conductivity and conductivity, such as copper, for example.
[0010] The means and variations described in the dependent claims enable advantageous improvements to the coil assembly described in independent claim 1.
[0011] Particularly advantageous, the circuit support may be formed as a multilayer printed circuit board having at least one conductive and thermally conductive inner layer connected to at least one thermal through-contact connection and at least one electrical through-contact connection. Here, the number and thickness of the individual thermally conductive and conductive inner layers and corresponding insulating layers, preferably made from copper, can be selected and preset, taking into account legal requirements, so as to activate and optimize the cooling paths of the individual windings of at least one coil.
[0012] In an advantageous configuration of the coil assembly, the conductive conductor path pieces of at least two windings may each be formed in a U-shape. In this case, one of the two end pieces of the at least two windings may be formed as a straight conductive conductor path piece, and the other end piece may be formed as an S-shaped conductive conductor path piece, where the portions of the two end pieces of the at least two windings inserted into the electrical through-contact connection extend axially parallel to each other outside at least one inner opening and outside the virtual extension of at least one inner opening. This makes it possible to achieve a particularly compact structural form of the coil assembly.
[0013] In a further advantageous configuration of the coil assembly, at least one of the at least two first thermal conduction structures can electrically interconnect two electrical through-contact connections, each into which one end piece of two adjacent windings of at least one coil winding is inserted, on the surface of the circuit support facing the coil, such that two adjacent windings of at least one electric coil winding are electrically connected in series. This allows, for example, the first end piece to form the input-side contact of the corresponding winding. The second end piece can form the output-side contact of the corresponding winding. This means that the second end piece, which forms the output-side contact of the first winding and is inserted into and electrically connected within the first through-contact connection, is thermally and electrically connected to the second through-contact connection via the corresponding first thermal conduction path structure, where the first end piece forming the input-side contact of the second winding is inserted and electrically connected. Here, the second end piece of the first winding portion and the first end piece of the second winding portion may be soldered together at the corresponding through-contact connection portion.
[0014] Alternatively, at least one of the at least two first thermal conductive structures may have an electrical through-contact connection formed as an elongated hole on the surface of the circuit support facing the coil, where two end pieces of two adjacent windings of at least one coil winding are inserted so as to be electrically connected to each other, such that the two adjacent windings of at least one coil are electrically connected in series. This means that a second end piece forming the output contact of the first winding and a first end piece forming the input contact of the second winding may be inserted into the same through-contact connection and electrically connected. Here, the second end piece of the first winding and the first end piece of the second winding may be soldered to the same through-contact connection. Such an electrical through-contact connection formed as an elongated hole allows the two end pieces of two adjacent windings to be easily electrically and thermally connected to each other. Furthermore, the relatively small distance between the two end pieces reduces the overall diameter of the coil assembly. This enhances the electrical connectivity through direct solder contact at the material-bonded connection between the two end pieces and the wall portion of the through-contact connection formed as an elongated hole.
[0015] In a further advantageous configuration of the coil assembly, at least one of the at least two first heat conduction structures may have connections for electrical components. Therefore, for example, a smoothing capacitor, an ohm resistor, or a contact terminal can be easily placed between the two windings of at least one coil.
[0016] In a further advantageous configuration of the coil assembly, the first end piece of the first winding portion of the winding may form a first contact or input-side contact of at least one coil, and the second end piece of the last winding portion of the winding may form a second contact or output-side contact of at least one coil, each being inserted into and connected in an electrically through-contact connection portion formed as a perforated hole.
[0017] In a further advantageous configuration of the coil assembly, at least two first heat conduction structures may be formed on the exposed surfaces of the circuit support facing the coil, in the direction of at least one inner opening below the magnetic core and / or in the direction away from the magnetic core outside the magnetic core. In particular, when formed in the direction of the magnetic core, the unused surface below the magnetic core can be used to save structural space for the first heat conduction structures. However, depending on the size of the circuit support, the first heat conduction structures may be formed on the outside around the magnetic core.
[0018] In a further advantageous configuration of the coil assembly, the shape and dimensions of at least two first heat conduction structures on the surface of the circuit support facing the coil, the shape and dimensions of at least two second heat conduction structures on the surface of the circuit support opposite to the coil, the shape and dimensions of at least one inner layer of the circuit support, and the number of thermal through-contact connections may be adaptable to thermal load conditions. This makes it easier to favorably form individual cooling paths for heat dissipation of individual windings of at least one coil to be optimally suited to the thermal conditions of the coil assembly.
[0019] In a further advantageous configuration of the coil assembly, on the surface of the circuit support opposite to the coil, at least one electrically insulating and thermally conductive layer may be provided between at least one cooling element and at least two second thermal conductive structures. Here, the area of the electrically insulating and thermally conductive layer may be larger than the area of the at least two second thermal conductive structures, which may be larger than the area of at least one cooling element. To compensate for non-uniformity and improve thermal transition, a good thermal conductive layer can be provided between the electrically insulating layer, the thermal conductive layer and at least one cooling element.
[0020] In a further advantageous configuration of the coil assembly, in order to avoid creepage between at least one electrical through-contact connection and at least one cooling element located on the surface of the circuit support opposite to the coil, the edge of at least one cooling element may have a first minimum distance from at least one electrical through-contact connection, the edge of at least one thermal through-contact connection may have a second minimum distance from at least one electrical through-contact connection that is smaller than the first minimum distance, the edges of at least two second heat-conducting structures may have a third minimum distance from at least one electrical through-contact connection that is smaller than the second minimum distance, and the edges of an electrically insulating and thermally conductive layer may have a fourth minimum distance from at least one electrical through-contact connection that is smaller than the third minimum distance. Here, these minimum distances are selected and predetermined with legal standards in mind.
[0021] In a further advantageous configuration of the coil assembly, the cooling assembly may include at least one additional cooling element, which may be mounted on the winding of at least one coil on the side of the coil that is opposite to the circuit support. Here, the at least one additional cooling element may be thermally coupled to the winding of at least one coil via at least one electrically insulating and thermally conductive structural component. This at least one additional cooling element may, in an advantageous form, also allow for heat dissipation "upward" of at least one coil of the coil assembly, in addition to heat dissipation "downward" of the individual windings of at least one electric coil of the coil assembly by the circuit support.
[0022] Embodiments of the present invention are shown in the drawings, and these embodiments will be described in more detail in the following specification. In these drawings, components or elements that perform the same or similar functions are denoted by the same reference numerals. [Brief explanation of the drawing]
[0023] [Figure 1]It is a schematic perspective view showing a first embodiment of a coil assembly according to the present invention. [Figure 2] It is a schematic plan view showing the coil assembly according to the present invention shown in FIG. 1 without a magnetic core. [Figure 3] It is a schematic perspective view showing two adjacent winding portions of the coil assembly according to the present invention shown in FIGS. 1 and 2. [Figure 4] It is a schematic plan view showing a part of a circuit support of the coil assembly according to the present invention shown in FIGS. 1 and 2. [Figure 5] It is a schematic cross-sectional view showing a part of a circuit support of the coil assembly according to the present invention shown in FIGS. 1 and 2. [Figure 6] It is a schematic plan view showing the circuit support of the coil assembly according to the present invention shown in FIGS. 1 and 2 without an electric coil. [Figure 7] It is a schematic view showing the circuit support of the coil assembly according to the present invention shown in FIGS. 1 and 2 from below without a cooling element, without an electrically insulating and thermally conductive layer. [Figure 8] It is a schematic view showing the circuit support of the coil assembly according to the present invention shown in FIGS. 1 and 2 from below. [Figure 9] It is a schematic partial perspective cross-sectional view showing a second embodiment of the coil assembly according to the present invention without a magnetic core.
Mode for Carrying Out the Invention
[0024] Embodiment of the Invention As is evident from Figures 1 to 9, illustrated embodiments of coil assemblies 1, 1A, and 1B according to the present invention each include one circuit support 2, at least one electric coil 5, the winding 7 of the electric coil 5 being wound around a magnetic core 6 surrounding at least one inner opening 6.1 by at least two winding sections 8 and penetrating at least one inner opening 6.1, and at least one cooling assembly 10, 10A, and 10B. Each of the at least two winding sections 8 has one conductive conductor path piece 8.1 having two end pieces 8.2 and 8.3, the two end pieces 8.2 and 8.3 are respectively inserted into and contact-connected electrical through-contact connection sections 4 provided within the circuit support 2. Here, these cooling assemblies 10, 10A, 10B have at least two first heat conduction structures 3, 11 in the region of the magnetic core 6 on the surface of the circuit support 2 facing the coil, and these at least two first heat conduction structures 3, 11 are thermally coupled to at least two corresponding second heat conduction structures 13, 14 on the surface of the circuit support 2 opposite to the coil via at least one thermal through-contact connection 12. At least two first heat conduction structures 3,11 are spaced apart from each other and each connected to at least one of a plurality of electrical through-contact connections 4, and at least two second heat conduction structures 13,14 are spaced apart from each other and thermally coupled to at least one cooling element 18 located on the surface of the circuit support 2 opposite to the coil, thereby forming one cooling path between the end pieces 8.2,8.3 of at least two windings 8, which are in contact with the corresponding electrical through-contact connections 4, and at least one cooling element 18.
[0025] As is further evident from Figure 1, the coil assembly 1 is configured as a common-mode choke for high-voltage or high-current applications. For this purpose, the magnetic core 6 is configured as a circular toroidal core 6A having an inner opening 6.1 in the illustrated embodiment and is positioned parallel to the surface of the circuit support 2. Two electric coils 5 windings 7 are wound around this toroidal core 6A in the illustrated embodiment. Here, the first coil 5A includes a first winding 7A having five winding sections 8A, 8B, 8C, 8D, and 8E. The second coil 5B is symmetrical to the first coil 5A and similarly includes a second winding 7B having five winding sections 8A, 8B, 8C, 8D, and 8E. Basically, only one coil or more than two coils may be arranged.
[0026] In alternative embodiments of coil assembly 1 not shown, the magnetic core 6 is configured as an elliptical or rectangular toroidal core 6A having an inner opening 6.1. In further alternative embodiments not shown, the toroidal core 6A has a central web, thereby the corresponding magnetic core 6 has two inner openings, regardless of its shape.
[0027] As is particularly clear from Figure 5, in the illustrated embodiment, the circuit support 2 is formed as a multilayer printed circuit board 2A having, for example, four conductive and thermally conductive inner layers 2.1 connected to at least one thermal through-contact connection 12 and at least one electrical through-contact connection 4.
[0028] As is further evident from Figures 1 to 3 and Figure 9, the conductive conductor path pieces 8.1 of the five simply exemplary wound sections 8A, 8B, 8C, 8D, and 8E of each coil 5A and 5B are each formed in a U-shape. Here, one first end piece 8.2 is formed as an S-shaped conductive conductor path piece, forming the input side contact of each wound section 8A, 8B, 8C, 8D, and 8E. A second end piece 8.3 is formed as a straight conductive conductor path piece, forming the output side contact of each wound section 8A, 8B, 8C, and 8D. The two end pieces 8.2 and 8.3 of each wound section 8A, 8B, 8C, 8D, and 8E inserted into the electrical through-contact connection 4 extend axially parallel to each other outside at least one inner opening 6.1 and outside the virtual extension of at least one inner opening 6.1. As is particularly evident from Figures 1, 2 and 6 to 8, the through-contact connection portion 4 is located on a common circle around the magnetic core 6 in the illustrated embodiment.
[0029] As is particularly clear from Figures 1, 2, and 6, in the illustrated embodiment, for each coil 5A, 5B, six first heat conduction structures 3, 11 are arranged on the surface of the circuit support 2 facing the coil, merely as an example. Here, each of the four first heat conduction structures 11 has a cake-like shape and an electrical through-contact connection portion 4 formed as an elongated hole 4B. Two end pieces 8.2, 8.3 of two adjacent winding portions 8A, 8B, 8C, 8D, 8E of the winding 7 of each coil 5 are inserted into this through-contact connection portion 4 so that the two adjacent winding portions 8A, 8B, 8C, 8D, 8E of the winding 7 of each coil 5 are electrically connected in series, and are electrically connected to each other. The cake-like first heat conduction structures 11 are arranged below the magnetic core 6 in the direction of at least one inner opening 6.1 on the exposed surface of the surface of the circuit support 2 facing the coil. Two of the first heat conduction structures 3 each have a web shape and a through-contact connection portion 4 formed as a hole 4A. The web-shaped first heat conduction structures 3 are formed on the outside of the magnetic core 6 in a direction away from the magnetic core 6.
[0030] Figure 4 shows an alternative configuration of the cake-shaped first heat conduction structure 11. Here, the cake-shaped first heat conduction structure 11 is formed on the exposed surface of the circuit support 2 facing the coil, in the direction of at least one inner opening 6.1, below and outside the magnetic core 6, as indicated by the dashed line.
[0031] As is further evident from Figures 1 and 2, the first end piece 8.2 of the first winding portion 8A of the first winding 7A of the first coil 5A is inserted into a through-contact connection portion 4 formed as a hole 4A of the web-shaped first heat conduction structure 3A located in the upper left of the figure, where it forms the first contact of the first coil 5A corresponding to the input side contact of the first coil 5A. The second end piece 8.3 of the first winding portion 8A of the first coil 5A, together with the first end piece 8.2 of the second winding portion 8B of the first coil 5A, is inserted into an electrical through-contact connection portion 4 formed as an elongated hole 4B of the cake-shaped heat conduction structure 11. The second end piece 8.3 of the second winding portion 8B of the first coil 5A, together with the first end piece 8.2 of the third winding portion 8C of the first coil 5A, is inserted into the electrical through-contact connection portion 4 formed as an elongated hole 4B in the cake-shaped heat conduction structure 11. The second end piece 8.3 of the third winding portion 8C of the first coil 5A, together with the first end piece 8.2 of the fourth winding portion 8D of the first coil 5A, is inserted into the electrical through-contact connection portion 4 formed as an elongated hole 4B in the cake-shaped heat conduction structure 11. The second end piece 8.3 of the fourth winding portion 8D of the first coil 5A, together with the first end pieces 8.2 of the fifth and last winding portions 8E of the first coil 5A, is inserted into the electrical through-contact connection portion 4 formed as an elongated hole 4B in the cake-shaped heat conduction structure 11. The second end pieces 8.3 of the fifth and final winding portion 8E of the first coil 5A are inserted into and made contact with the electrical through-contact connection portion 4, which is formed as a perforated hole 4A of the web-shaped heat conduction structure portion 3B located in the upper right of the figure, forming the second contact of the first coil 5A, which corresponds to the output side contact of the first coil 5A. The same procedure is followed in configurations with many or few winding portions.
[0032] As is further evident from Figures 1 and 2, the first end piece 8.2 of the first winding portion 8A of the second winding 7B of the second coil 5B is inserted into a through-contact connection portion 4 formed as a hole 4A of the web-shaped first heat conduction structure 3A located in the lower right of the figure, where it forms the first contact of the second coil 5B corresponding to the input side contact of the second coil 5B. The second end piece 8.3 of the first winding portion 8A of the second coil 5B, together with the first end piece 8.2 of the second winding portion 8B of the second coil 5B, is inserted into an electrical through-contact connection portion 4 formed as an elongated hole 4B of the cake-shaped heat conduction structure 11. The second end piece 8.3 of the second winding portion 8B of the second coil 5B, together with the first end piece 8.2 of the third winding portion 8C of the second coil 5B, is inserted into the electrical through-contact connection portion 4 formed as an elongated hole 4B in the cake-shaped heat conduction structure 11. The second end piece 8.3 of the third winding portion 8C of the second coil 5B, together with the first end piece 8.2 of the fourth winding portion 8D of the second coil 5B, is inserted into the electrical through-contact connection portion 4 formed as an elongated hole 4B in the cake-shaped heat conduction structure 11. The second end piece 8.3 of the fourth winding portion 8D of the second coil 5A, together with the first end pieces 8.2 of the fifth and last winding portions 8E of the second coil 5B, is inserted into the electrical through-contact connection portion 4 formed as an elongated hole 4B in the cake-shaped heat conduction structure 11. The second end pieces 8.3 of the fifth and final windings 8E of the second coil 5B are inserted into and connected to an electrical through-contact connection portion 4 formed as a perforated hole 4A of the web-shaped heat conduction structure 3B located in the lower left of the figure, forming a second contact of the second coil 5B corresponding to the output contact of the second coil 5B. An electrical load, such as an inverter for a three-phase motor, can be connected between the upper web-shaped heat conduction structure 3B located on the right in the figure and connected to the output contact of the first coil 5A, and the lower web-shaped heat conduction structure 3A located on the right in the figure and connected to the input contact of the second coil 5B. A DC voltage supply can be connected to each of the two web-shaped heat conduction structures 3 located on the left in the figure.As a result, a positive DC voltage supply can be applied to the upper web-shaped heat conduction structure 3A, which is located on the left side in the figure and connected to the input contact of the first coil 5A. A negative DC voltage supply can be connected to the lower web-shaped heat conduction structure 3B, which is located on the left side in the figure and connected to the output contact of the second coil 5B. The same can be done with configurations that have many or few windings.
[0033] In the illustrated embodiment, the electrical through-contact connection portion 4 has a conductive wall portion 4.1 or sleeve, and individual end pieces 8.2, 8.3 into which the wound portions 8A, 8B, 8C, 8D, 8E of the two coils 5A, 5B are inserted are connected to these wall portions 4.1 or sleeve by material-bonded connection portions 9, preferably by soldered connection portions.
[0034] In an alternative embodiment of coil assembly 1 not shown, each of the two coils 5A and 5B has four cake-shaped first heat conduction structures 11, each having two electrical through-contact connections 4 formed as holes 4A on the surface of the circuit support 2 facing the coils, into which one end piece 8.2, 8.3 of two adjacent windings 8A, 8B, 8C, 8D, 8E of the windings 7 of each coil 5A and 5B is inserted. Here, the cake-shaped first heat conduction structures 11 connect the two adjacent windings 8A, 8B, 8C, 8D, 8E of each coil 5A and 5B so that they are electrically connected in series.
[0035] As is further evident from Figure 6, each of the two cake-shaped first heat conduction structures 11 of the two coils 5A and 5B has one connection path 11.1 for the electrical component C. In the illustrated embodiment, the two electrical component C each corresponds to one smoothing capacitor.
[0036] As is further evident from Figure 7, in the illustrated embodiment of coil assembly 1A, six second heat conduction structures 13, 14 are arranged (exemplarily, respectively) for each coil 5A, 5B on the surface of the circuit support 2 opposite to the coil. Here, the four second heat conduction structures 14 for each coil 5A, 5B each have a cake-like shape and are thermally connected to the cake-like first heat conduction structures 11 on the surface of the circuit support 2 facing the coil via a plurality of thermal through-contact connections 12. The cake-like second heat conduction structures 12 are located below the magnetic core 6 on the exposed surface of the circuit support 2 opposite to the coil, in the direction of at least one inner opening 6.1. Two of the second heat conduction structures 13 of each coil 5A and 5B each have a web shape and are thermally connected to the web-shaped first heat conduction structure 3 on the surface of the circuit support 2 facing the coil via a plurality of thermal penetrating contact connections 12. The web-shaped second heat conduction structures 13 are formed on the outside of the magnetic core 6 in a direction away from the magnetic core 6.
[0037] As is further evident from Figures 5 and 8, on the surface of the circuit support 2 opposite to the coil, at least one electrically insulating and thermally conductive layer 15 is provided between at least one cooling element 18 and at least two second heat conduction structures 13, 14. Here, the area of the electrically insulating and thermally conductive layer 15 is larger than the area of at least one cooling element 18 and larger than the area of at least two second heat conduction structures 13, 14. Particularly as is further evident from Figure 8, the first cooling element 18 located below the magnetic core 6 is formed as a circular cooling dome 18A in the illustrated embodiment. Further cooling elements 18 located outside the magnetic core 6 are each formed as rectangular parallelepiped-shaped cooling blocks 18B in the illustrated embodiment.
[0038] As is further evident from Figure 5, the edge of the cooling element 18 formed as a cooling dome 18A has a first minimum distance MA1 from the illustrated electrical through-contact connection 4. The edge of the thermal through-contact connection 12, which is located next to the electrical through-contact connection 4, has a second minimum distance MA2 from the electrical through-contact connection 4 that is smaller than the first minimum distance MA1. The edge of the second heat-conducting structure 14 has a third minimum distance MA3 from the electrical through-contact connection 4 that is smaller than the second minimum distance MA2. The edge of the electrically insulating and thermally conductive layer 15 has a fourth minimum distance MA4 from at least one electrical through-contact connection 4 that is smaller than the third minimum distance MA3. Here, these minimum distances MA1, MA2, MA3, MA4 are selected and preset in consideration of legal standards to avoid creepage zones even in high-voltage or high-current applications.
[0039] To compensate for non-uniformity and improve thermal transition, in the illustrated embodiment, a thermally conductive layer 16 is provided between the electrically insulating and thermally conductive layer 15 and at least one cooling element 18.
[0040] The shape and dimensions of the first heat conduction structures 3,11 on the surface of the circuit support 2 facing the coil, the shape and dimensions of the second heat conduction structures 13,14 on the surface of the circuit support 2 opposite to the coil, the shape and dimensions of the inner layer 2.1 of the circuit support 2, and the number of thermal through-contact connection parts 12 are adapted to the thermal load conditions.
[0041] As is further evident from Figure 9, the illustrated second embodiment of coil assembly 1B substantially corresponds to the first embodiment of coil assembly 1A shown in Figures 1 to 8, and therefore the repetition of the description of the same components is omitted. Unlike the first embodiment of coil assembly 1A, the second embodiment of cooling assembly 10B of the illustrated second embodiment of coil assembly 1B has at least one additional cooling element 19, which is mounted on the winding 7 of at least one coil 5 on the side of the coil 5 opposite to the circuit support 2. To improve heat transfer, the illustrated additional cooling element 19 is thermally coupled to the winding 7 of at least one coil 5 via at least one electrically insulating and thermally conductive structural part 20.
Claims
1. A coil assembly (1), Circuit support (2) and At least one electric coil (5), the winding (7) of the electric coil (5) is wound around a magnetic core (6) surrounding at least one inner opening (6.1) by at least two winding portions (8), and the at least one electric coil (5) penetrates the at least one inner opening (6.1), At least one cooling assembly (10) and Equipped with, Each of the at least two winding portions (8) has one conductive conductor path piece (8.1) having two end pieces (8.2, 8.3), and the two end pieces (8.2, 8.3) are inserted into and connected to an electrical through-contact connection portion (4) provided within the circuit support (2). The cooling assembly (10) has at least two first heat conduction structures (3, 11) in the region of the magnetic core (6) on the surface of the circuit support (2) facing the coil, and the at least two first heat conduction structures (3, 11) are thermally coupled to at least two corresponding second heat conduction structures (13, 14) via at least one thermal through-contact connection (12) on the surface of the circuit support (2) opposite to the coil. The coil assembly (1) is characterized in that at least two first heat conduction structures (3, 11) are spaced apart from each other and each is connected to at least one of a plurality of electrical through-contact connections (4), and at least two second heat conduction structures (13, 14) are spaced apart from each other and are thermally coupled to at least one cooling element (18) located on the surface of the circuit support (2) opposite to the coil, thereby forming a cooling path between the end pieces (8.2, 8.3) of the at least two windings (8) which are in contact with the corresponding electrical through-contact connections (4) and the at least one cooling element (18).
2. The coil assembly (1) according to claim 1, wherein the circuit support (2) is formed as a multilayer printed circuit board (2A) having at least one conductive and thermally conductive inner layer (2.1) connected to the at least one thermal through-contact connection portion (12) and the at least one electrical through-contact connection portion (4).
3. The coil assembly (1) according to claim 1 or 2, wherein the conductive conductor path pieces (8.1) of the at least two winding portions (8) are each formed in a U shape, one end piece (8.2) of the two end pieces (8.2, 8.3) of the at least two winding portions (8) is formed as a straight conductive conductor path piece, the other end piece (8.3) of the two end pieces (8.2, 8.3) is formed as an S-shaped conductive conductor path piece, and the portions of the two end pieces (8.2, 8.3) of the at least two winding portions (8) inserted into the electrical through-contact connection portion (4) extend axially parallel to each other outside the at least one inner opening (6.1) and outside the virtual extension portion of the at least one inner opening (6.1).
4. The coil assembly (1) according to any one of claims 1 to 3, wherein at least one of the at least two first heat conduction structures (11) electrically connects two electrical through-contact connections (4) on the surface of the circuit support (2) facing the coil, into which one end piece (8.2, 8.3) of each of two adjacent winding portions (8) of the winding (7) of the at least one coil (5) is inserted, such that the two adjacent winding portions (8) of the winding (7) of the at least one coil (5) are electrically connected in series.
5. The coil assembly (1) according to any one of claims 1 to 3, wherein at least one of the at least two first heat conduction structures (11) has an electrical through-contact connection portion (4) formed as an elongated hole (4B) on the surface of the circuit support (2) facing the coil, and two end pieces (8.2, 8.3) of two adjacent winding portions (8) of the winding (7) of the at least one coil (5) are inserted into the electrical through-contact connection portion (4) such that the two adjacent winding portions (8) of the winding (7) of the at least one coil (5) are electrically connected in series and electrically connected to each other.
6. The coil assembly (1) according to claim 4 or 5, wherein at least one of the at least two first heat conduction structures (11) has a connection path (11.1) for an electrical component (C).
7. The coil assembly (1) according to any one of claims 1 to 6, wherein the end pieces (8.2, 8.3) of the first winding portion (8A) of the winding (7) form a first contact of the at least one coil (5), and the end pieces (8.2, 8.3) of the last winding portion (8E) of the winding (7) form a second contact of the at least one coil (5), and each is inserted into an electrically through-contact connection portion (4) formed as a perforated hole portion (4A) and connected in contact.
8. The coil assembly (1) according to any one of claims 1 to 7, wherein the at least two first heat conduction structures (3, 11) are formed on the exposed surface of the circuit support (2) facing the coil in the direction of the at least one inner opening (6.1) below the magnetic core (6) and / or in the direction away from the magnetic core (6) outside the magnetic core (6).
9. The coil assembly (1) according to any one of claims 1 to 8, wherein the magnetic core (6) is formed as a circular, elliptical, or rectangular toroidal core (6A) having or not having a central web.
10. The coil assembly (1) according to any one of claims 2 to 9, wherein the shape and dimensions of at least two first heat conduction structures (3, 11) on the surface of the circuit support (2) facing the coil, the shape and dimensions of at least two second heat conduction structures (13, 14) on the surface of the circuit support (2) opposite to the coil, the shape and dimensions of at least one inner layer (2.1) of the circuit support (2), and the number of thermal through-contact connections (12) are adaptable to thermal load conditions.
11. The coil assembly (1) according to any one of claims 1 to 10, wherein at least one electrically insulating and thermally conductive layer (15) is provided between the at least one cooling element (18) and the at least two second heat-conducting structural parts (13, 14) on the surface of the circuit support (2) opposite to the coil.
12. The coil assembly (1) according to claim 11, wherein the area of the electrically insulating and thermally conductive layer (15) is greater than the area of the at least two second heat-conducting structural parts (13, 14), which is greater than the area of the at least one cooling element (18).
13. The edge of the at least one cooling element (18) has a first minimum distance (MA1) from the at least one electrical through-contact connection portion (4), The edge of the at least one thermal through-contact connection portion (12) has a second minimum distance (MA2) smaller than the first minimum distance (MA1) with respect to the at least one electrical through-contact connection portion (4). The edges of the at least two second heat conduction structures (14) have a third minimum distance (MA3) that is smaller than the second minimum distance (MA2) with respect to the at least one electrical through-contact connection (4). The coil assembly (1) according to claim 11 or 12, wherein the edge of the electrically insulating and thermally conductive layer (15) has a fourth minimum spacing (MA4) smaller than the third minimum spacing (MA3) with respect to the at least one electrically through-contact connection portion (4).
14. The coil assembly (1) according to any one of claims 1 to 13, wherein the cooling assembly (10) includes at least one further cooling element (19), the at least one further cooling element (19) resting on the winding (7) of the at least one coil (5) on the side of the at least one coil (5) opposite to the circuit support (2).
15. The coil assembly (1) according to claim 14, wherein the at least one further cooling element (19) is thermally coupled to the winding (7) of the at least one coil (5) via at least one electrically insulating and thermally conductive structural part (20).