Cooling arrangement for cooling a power transistor for a fast charging station for electric vehicles

Abstract

The invention relates to a cooling arrangement for cooling a power transistor for a fast charging station (1) for electric vehicles, wherein the cooling arrangement (4) comprises a cooling package (5), wherein the cooling package (5) comprises a first power transistor (6), a first ceramic layer (7), a spring (8) and an electrically insulating spring carrier (9), wherein the cooling arrangement (4) comprises a radiator arrangement (10) and a heat conductor (11), wherein the heat conductor (11) is attached to the radiator arrangement (10), wherein the cooling package (5) is attached to the heat conductor (11), wherein, starting from the heat conductor (11), the first ceramic layer (7), the first power transistor (6), the spring carrier (9) and the spring (8) are arranged one above the other in this order, wherein the spring (8) pushes the first power transistor (6) in the direction of the heat conductor (11).

Description

[0001] The present invention relates to a cooling arrangement for cooling a power transistor for a fast charging station for electric vehicles according to claim 1, a method for assembling a cooling arrangement according to claim 13, a power module with a cooling arrangement according to claim 14 and a fast charging station for electric vehicles according to claim 15.

[0002] Fast charging stations, also known as high-performance chargers, are DC charging stations for electric vehicles, especially cars, but also trucks, ships, and the like. One challenge with fast charging stations is cooling the power electronics, especially the power transistors, in a confined space.

[0003] The invention addresses the problem of improving this cooling in a small space.

[0004] The above problem is solved by the features of claim 1.

[0005] The essential basic consideration is that a cooling arrangement is provided in which a power transistor is pressed by a spring towards a heat conductor, with measures for electrical insulation being taken between the spring and the power transistor as well as between the power transistor and the heat conductor.

[0006] Specifically, a cooling arrangement for cooling a power transistor for a fast charging station for electric vehicles is proposed, wherein the cooling arrangement comprises a cooling package, the cooling package comprising a first power transistor, a first ceramic layer, a spring and an electrically insulating spring carrier, the cooling arrangement comprising a radiator arrangement and a heat conductor, the heat conductor being attached to the radiator arrangement, the cooling package being attached to the heat conductor, the first ceramic layer, the first power transistor, the spring carrier and the spring being arranged one above the other in that order starting from the heat conductor, the spring pressing the first power transistor towards the heat conductor.

[0007] Claim 2 specifies preferred embodiments with a fastening element. In embodiments according to claim 3, two power transistors are jointly attached to the heat conductor, thereby reducing the number of parts and the assembly effort. Embodiments according to claims 4 to 9 relate to the fastening of the components of the cooling arrangement and the electrical shielding of the components of the cooling arrangement.

[0008] In a preferred embodiment according to claim 10, at least one power transistor is arranged next to a circuit board, thereby simplifying its thermal connection. The heat conductor can bridge the gap between a height of the circuit board and the radiator arrangement, thus enabling the mounting of the power transistor. Claim 11 relates to the radiator arrangement. Claim 12 specifies measures for simplifying the assembly of the cooling arrangement.

[0009] According to a further teaching according to claim 13, which has independent significance, a method for assembling a proposed cooling arrangement is claimed, wherein the first ceramic layer and preferably the second ceramic layer is placed on the heat conductor, wherein the first power transistor is placed on the first ceramic layer and preferably the second power transistor is placed on the second ceramic layer, wherein the spring carrier is placed on the heat conductor, preferably, wherein when placing the spring carrier on the heat conductor the spring carrier is centered relative to the heat conductor.

[0010] Reference may be made to all statements regarding the proposed cooling arrangement.

[0011] According to a further teaching according to claim 14, which also has independent significance, a power module with a proposed cooling arrangement is claimed, wherein the power module has at least one fan whose airflow passes through the radiator arrangement, in particular the cooling fins, preferably wherein the airflow passes through and / or around the cooling package.

[0012] Reference may be made to all statements regarding the proposed cooling arrangement and the proposed procedure.

[0013] According to a further teaching as per claim 15, which also has independent significance, a fast charging station for electric vehicles with at least one proposed power module is claimed.

[0014] Reference may be made to all statements concerning the proposed cooling arrangement, the proposed method and the proposed power module.

[0015] The invention will now be explained in more detail with reference to a drawing that merely illustrates exemplary embodiments. The drawing shows Fig. 1 a proposed fast charging station, Fig. 2 power modules in the fast charging station, Fig. 3 the cooling arrangement and a cross-section through the cooling arrangement, Fig. 4 a perspective view of the cooling arrangement, Fig. 5 A perspective view of the cooling arrangement with several power transistors, with various components hidden, Fig. 6 a power module with an open side panel and Fig. 7 a schematic section through a power module and the airflow of a fan of the power module.

[0016] Fig. Figure 1 shows an external view of a proposed fast charging station 1 for electric vehicles. This station has at least one connection point 2 for an electric vehicle, in this case a permanently attached charging cable. Preferably, the fast charging station 1 has at least, and in this case exactly, two connection points 2. A fast charging station 1 is used to charge an electric vehicle using direct current and a power output of usually at least 50 kW. The fast charging station 1 is typically connected to an alternating current network for this purpose.

[0017] As seen in the open view in Fig. As can be seen from Figure 2, the fast charging station 1 has at least one individually controllable power module 3. Here, the fast charging station 1 has seven power modules 3, each of which provides a portion of the total power of the fast charging station 1, for example, 30 kW each. The power modules 3 can be, and preferably flexibly, distributed among the connection points 2.

[0018] The term "individually manageable" is to be interpreted broadly here. For example, power module 3 weighs approximately 39 kg, so it is not easy to handle. However, it can be removed individually, and the components of power module 3 are not individually installed in fast charging station 1.

[0019] The embodiment shown in the figures, which is preferred in this respect, relates to a cooling arrangement 4 for cooling, in particular by air cooling, a power transistor for a fast charging station 1 for electric vehicles. Here, and preferably, this power transistor is arranged in the power module 3. There, the power transistor can be part of an AC / DC converter or a DC / DC converter.

[0020] The Fig. Figures 3 to 5 show different views of the cooling arrangement 4. The cooling arrangement 4 includes a cooling package 5. The cooling package 5 includes a first power transistor 6, a first ceramic layer 7, a spring 8, and an electrically insulating spring carrier 9.

[0021] The cooling arrangement 4 further comprises a radiator arrangement 10 and a heat conductor 11, which in cross-section are Fig. 3 are clearly recognizable. Fig. Figure 6 shows the power module 3 with its side panel 12 open, allowing a view of the radiator assembly 10. The first power transistor 6 is in Fig. 6 not recognizable.

[0022] The heat conductor 11, here and preferably a metal beam, is attached to the radiator assembly 10. The cooling package 5 is attached to the heat conductor 11. Starting from the heat conductor 11, the first ceramic layer 7, the first power transistor 6, the spring carrier 9, and the spring 8 are arranged one above the other in that order. Fig. The sequence is recognizable in section 3. The spring 8 pushes the first power transistor 6 towards the heat conductor 11. This improves the thermal connection of the first power transistor 6. The spring 8 is preferably made of spring steel and is therefore electrically insulated from the first power transistor 6 via the spring carrier 9. The insulation is designed to withstand the currents and voltages of the first power transistor 6. The ceramic also provides electrical insulation between the power transistor and the heat conductor 11.

[0023] Clearly recognizable in the Fig. 4 and Fig. Section 5 states that the cooling package 5 preferably has at least one fastening element 13, or here two fastening elements 13. The cooling package 5 is attached to the heat conductor 11 by means of the fastening element 13. Preferably, the fastening element 13 projects through the spring 8 and / or the spring carrier 9 and / or projects past the first power transistor 6 and / or the first ceramic layer 7. Here, the fastening element 13 is arranged laterally next to the first power transistor 6. Preferably, the fastening element 13 is elongated, particularly cylindrical. More preferably, the fastening element 13 is a screw or a bolt. Here, two screws are provided as fastening elements 13.

[0024] It is also shown, and preferably, that the cooling package 5 comprises a second power transistor 14, and that, starting from the heat conductor 11, a second ceramic layer 15, the second power transistor 14, the spring carrier 9, and the spring 8 are arranged one above the other in that order. The first power transistor 6 and the second power transistor 14 can be arranged side by side starting from the heat conductor 11. Both power transistors 6 and 14 are attached together to the heat conductor 11. Accordingly, and preferably, the spring 8 and / or the spring carrier 9 and / or the fastening element 13 are arranged between the power transistors 6 and 14.

[0025] Furthermore, and preferably, the fastening element 13 secures the spring 8 to the spring carrier 9 and the spring carrier 9 to the heat conductor 11. Preferably, the fastening element 13 engages an opening in the heat conductor 11 through an opening in the spring 8 and / or through an opening in the spring carrier 9. Here, and preferably, the fastening element 13 is screwed into a thread in the heat conductor 11. This results in a compact arrangement of the components of the cooling package 5 for mounting two power transistors 6, 14 and for electrically isolating the components from each other, where necessary.

[0026] Here, and preferably, the spring carrier 9 electrically shields the spring 8 and preferably the fastening element 13 from the first power transistor 6 and preferably the second power transistor 14, and / or the first ceramic layer 7 electrically shields the first power transistor 6 and preferably the second ceramic layer 15 the second power transistor 14 from the heat conductor 11.

[0027] Furthermore, and preferably, it is provided that the heat conductor 11 and / or the spring 8 and / or the fastening element 13 are connected to a neutral potential or protective conductor potential. The arrangement becomes particularly compact if, preferably, the spring 8 is electrically connected to the heat conductor 11 via the fastening element 13.

[0028] Furthermore, the spring 8 may exert a contact force of at least 100 N, preferably at least 130 N, and more preferably at least 200 N, on the first power transistor 6 and preferably the second power transistor 14 in the direction of the heat conductor 11. The fastening element 13 may be the cause of this contact force, and the spring 8 may transmit a force exerted by the fastening element 13 to the first power transistor 6 and preferably the second power transistor 14.

[0029] It should be noted here that the power transistors 6, 14, the spring 8, the spring holder 9, the heat conductor 11, and the fastening element 13 are, and preferably are, separate components. The heat conductor 11 and the radiator assembly 10 can be designed as a single unit, but are, and preferably are, also separate components. The spring 8 and / or the spring holder 9 and / or the heat conductor 11 and / or the fastening element 13 are, and preferably are, each designed as a single unit.

[0030] With regard to the perspective views of the Fig. 3 and Fig. In this case, and preferably, the spring carrier 9 provides a first receptacle 16 for the spring 8, which has side walls 12 projecting away from the first power transistor 6 on three sides and a base 17 between the spring 8 and the first power transistor 6. Preferably, the spring carrier 9 provides a second receptacle 18 for the spring 8, which has side walls 12 projecting away from the second power transistor 14 on three sides and a base 17 between the spring 8 and the second power transistor 14. Further preferably, the first receptacle 16 and the second receptacle 18 have, on a side facing the mounting element 13, a side wall 19 projecting towards the heat conductor and / or no side wall 12 projecting away from the respective power transistor. The resulting trough increases the effective distances between the spring 8 and the power transistors 6, 14, thus improving the electrical insulation.

[0031] For improved thermal connection and easy assembly, a thermal pad 20 can be arranged between the heat conductor 11 and the first ceramic layer 7 and preferably between the heat conductor 11 and the second ceramic layer 15 and / or between the first ceramic layer 7 and the first power transistor 6 and preferably between the second ceramic layer 15 and the second power transistor 14, in particular in each case.

[0032] In Fig. As can be clearly seen in Figure 3, at least one power transistor is arranged next to a circuit board 21. The power transistor, for example the first power transistor 6, is connected to this circuit board 21. "Next to" refers to the circuit board surfaces. Additionally or alternatively, the cooling arrangement 4 may have several, in particular at least three, cooling packages 5 attached to the heat conductor 11. Fig. Figure 5 shows four cooling packages, but most of the components are hidden in all but one. This makes the mounting details described below more visible. The power transistors 6 and 14 are shown in each case.

[0033] Preferably, the heat conductor 11 runs along an edge of the circuit board 21. The heat conductor 11 can be a beam and / or made of aluminum. Preferably, the power transistors 6, 14 of the cooling packages 5 are connected to the circuit board 21 and arranged next to it. The legs 22, which are electrically connected to the power transistors 6, 14, bridge a gap, preferably provided here, between the power transistors 6, 14 and the circuit board 21. The heat conductor 11 preferably bridges the gap between a plane of the circuit board 23 and a parallel plane of the radiator arrangement 24.

[0034] Furthermore, it is preferably provided here that the radiator arrangement 10 has cooling fins 25 which extend away from the heat conductor 11 from the power transistors 6, 14 ( Fig. 3 on average, Fig. 6). Fig. Figure 7 also shows that an airflow 26 from a fan 27 of the power module 3 flows here and preferably through the cooling fins 25 and through and / or over the cooling package 5. This two-sided cooling is particularly preferred.

[0035] In summary, the Fig. 3 to 5 and also with regard to the cooling packages not fully shown 5 in Fig. Figure 5 shows that the heat conductor 11 preferably has a guide arrangement, in particular at least one guide opening 28, for the spring carrier 9. Additionally or alternatively, and shown here, the spring carrier 9 has a guide arrangement for the heat conductor 11, in particular a guide pin 29 for engaging in the guide opening 28 and / or guide clips 30 for gripping the heat conductor 11. Furthermore, additionally or alternatively, and shown here, the spring carrier 9 has a guide arrangement, in particular at least one guide receptacle 31, for the first power transistor 6 and preferably the second power transistor 14. The respective power transistor 6, 14 can be received directly in the guide receptacle 31 or with other components interposed.Furthermore, the spring carrier 9 can have guide webs 32 for the spring 8, so that the openings of the spring 8 and the spring carrier 9 are aligned during assembly. The guide webs 32 preferably each have a groove. The spring 8 preferably has a corresponding groove. The grooves are located in... Fig. 4 is only vaguely recognizable and not marked with a reference numeral. The spring carrier 9 centers the spring 8 here, preferably by means of the grooves, so that the openings for the screws of the spring 8 and the spring carrier 9 are aligned. Here, and preferably, the spring carrier 9 correctly aligns the spring 8 in two dimensions, here parallel to the plane of the circuit board 23.

[0036] According to a further teaching, a method for assembling a proposed cooling arrangement 4 is proposed, wherein the first ceramic layer 7 and preferably the second ceramic layer 15 are placed on the heat conductor 11, wherein the first power transistor 6 is placed on the first ceramic layer 7 and preferably the second power transistor 14 is placed on the second ceramic layer 15, and wherein the spring carrier 9 is placed on the heat conductor 11. Preferably, the spring carrier 9 is centered relative to the heat conductor 11 when it is placed on it. This centering can be achieved by one or more of the aforementioned guide arrangements.

[0037] Reference may be made to all explanations regarding the proposed cooling arrangement 4.

[0038] According to a further teaching, a power module 3 with a proposed cooling arrangement 4 is proposed, wherein the power module 3 has at least one fan 27, the airflow 26 of which flows through the radiator arrangement 10, in particular the cooling fins 25, preferably, wherein the airflow 26 flows through and / or around the cooling package 5.

[0039] Reference may be made to all statements concerning the proposed cooling arrangement 4 and the proposed procedure.

[0040] According to another teaching, a fast charging station 1 for electric vehicles with at least one proposed power module 3 is proposed.

[0041] Reference may be made to all details concerning the proposed cooling arrangement 4, the proposed method and the proposed power module 3. Reference symbol list 1 fast charging station 2 connection point 3 Power module 4 Cooling arrangement 5 cooling packs 6 first power transistor 7 first ceramic layer 8 springs 9 spring carriers 10 Radiator arrangement 11 Heat conductors 12 side wall 13 Fastening element 14 second power transistor 15 second ceramic layer 16 first recording 17 Floor 18 second recording 19 Side wall projecting towards the heat conductor 20 thermal pads 21 circuit boards 22 Leg 23. Level of the circuit board 24 Level of radiator arrangement 25 cooling fins 26 Airflow 27 fans 28 Guide opening 29 Guide pen 30 guide clip 31 Guided tour 32 Guide bridge

Claims

[1] Cooling arrangement for cooling a power transistor for a rapid charging station (1) for electric vehicles, wherein the cooling arrangement (4) has a cooling package (5), wherein the cooling package (5) has a first power transistor (6), a first ceramic layer (7), a spring (8) and an electrically insulating spring support (9), wherein the cooling arrangement (4) has a radiator arrangement (10) and a heat conductor (11), wherein the heat conductor (11) is fastened to the radiator arrangement (10), wherein the cooling package (5) is fastened to the heat conductor (11), wherein, starting from the heat conductor (11), the first ceramic layer (7), the first power transistor (6), the spring support (9) and the spring (8) are arranged one above the other in this order, wherein the spring (8) presses the first power transistor (6) in the direction of the heat conductor (11). [2] Cooling arrangement according to claim 1, characterized bythat the cooling package (5) has at least one fastening element (13), that the cooling package (5) is fastened to the heat conductor (11) by means of the fastening element (13), that the fastening element (13) projects through the spring (8) and / or the spring carrier (9) and / or projects past the first power transistor (6) and / or the first ceramic layer (7), preferably that the fastening element (13) is elongated, in particular cylindrical, further preferably that the fastening element (13) is a screw or a bolt. [3] Cooling arrangement according to claim 1 or 2, characterized bythat the cooling package (5) has a second power transistor (14), that starting from the heat conductor (11) a second ceramic layer (15), the second power transistor (14), the spring support (9) and the spring (8) are arranged one above the other in this order, preferably that the first power transistor (6) and the second power transistor (14) are arranged next to one another starting from the heat conductor (11), further preferably that the spring (8) and / or the spring support (9) and / or the fastening element (13) are arranged between the power transistors (6, 14). [4] Cooling arrangement according to claim 2 or 3, characterized bythat the fastening element (13) fastens the spring (8) to the spring carrier (9) and the spring carrier (9) to the heat conductor (11), preferably engages through an opening in the spring (8) and / or through an opening in the spring carrier (9) into an opening in the heat conductor (11), in particular is screwed into a thread of the heat conductor (11). [5] Cooling arrangement according to one of the preceding claims, characterized by that the spring carrier (9) electrically shields the spring (8) and preferably the fastening element (13) from the first power transistor (6) and preferably the second power transistor (14), and / or that the first ceramic layer (7) electrically shields the first power transistor (6) and preferably the second ceramic layer (15) electrically shields the second power transistor (14) from the heat conductor (11). [6] Cooling arrangement according to one of the preceding claims, characterized bythat the heat conductor (11) and / or the spring (8) and / or the fastening element (13) is connected to a zero potential or protective conductor potential, preferably that the spring (8) is electrically connected to the heat conductor (11) via the fastening element (13). [7] Cooling arrangement according to one of the preceding claims, characterized by that the spring (8) exerts a contact pressure of at least 100 N, preferably at least 130 N, more preferably at least 200 N, on the first power transistor (6) and preferably the second power transistor (14) in the direction of the heat conductor (11), preferably that the fastening element (13) is the cause of the contact pressure and the spring (8) transmits a force exerted by the fastening element (13) to the first power transistor (6) and preferably the second power transistor (14). [8] Cooling arrangement according to one of the preceding claims, characterized byin that the spring carrier (9) provides a first receptacle (16) for the spring (8), which has side walls (12) projecting away from the first power transistor (6) on three sides and a base (17) between the spring (8) and the first power transistor (6), preferably in that the spring carrier (9) provides a second receptacle (18) for the spring (8), which has side walls (12) projecting away from the second power transistor (14) on three sides and a base (17) between the spring (8) and the second power transistor (14), further preferably in that the first receptacle (16) and the second receptacle (18) have, on a side facing the fastening element (13), a side wall (19) projecting towards the heat conductor and / or no side wall (12) projecting away from the respective power transistor. [9] Cooling arrangement according to one of the preceding claims, characterized bythat between the heat conductor (11) and the first ceramic layer (7) and preferably between the heat conductor (11) and the second ceramic layer (15) and / or between the first ceramic layer (7) and the first power transistor (6) and preferably between the second ceramic layer (15) and the second power transistor (14), in particular in each case, a heat conducting pad (20) is arranged. [10] Cooling arrangement according to one of the preceding claims, characterized bythat at least one power transistor is arranged next to a circuit board (21), and / or that the cooling arrangement (4) has a plurality of, in particular at least three, cooling packages (5) which are fastened to the heat conductor (11), preferably that the heat conductor (11) runs along an edge of the circuit board (21) and / or is a bar and / or is made of aluminum, further preferably that the power transistors (6, 14) of the cooling packages (5) are connected to the circuit board (21) and are arranged next to the circuit board (21). [11] Cooling arrangement according to one of the preceding claims, characterized by that the radiator arrangement (10) has cooling fins (25) which, starting from the heat conductor (11), protrude away from the power transistors (6, 14). [12] Cooling arrangement according to one of the preceding claims, characterized bythat the heat conductor (11) has a guide arrangement, in particular at least one guide opening (28), for the spring carrier (9), and / or that the spring carrier (9) has a guide arrangement for the heat conductor (11), in particular a guide pin (29) for engaging in the guide opening (28) and / or guide clamps (30) for encompassing the heat conductor (11), and / or that the spring carrier (9) has a guide arrangement, in particular at least one guide receptacle (31), for the first power transistor (6) and preferably the second power transistor (14). [13] Method for assembling a cooling arrangement (4) according to one of the preceding claims, wherein the first ceramic layer (7) and preferably the second ceramic layer (15) is placed on the heat conductor (11), wherein the first power transistor (6) is placed on the first ceramic layer (7) and preferably the second power transistor (14) is placed on the second ceramic layer (15), wherein the spring carrier (9) is placed on the heat conductor (11), preferably wherein when the spring carrier (9) is placed on the heat conductor (11), the spring carrier (9) is centered relative to the heat conductor (11). [14] Power module with a cooling arrangement (4) according to one of the preceding claims, wherein the power module (3) has at least one fan (27) whose air flow (26) flows through the radiator arrangement (10), in particular the cooling fins (25), preferably, wherein the air flow (26) flows through and / or around the cooling package (5). [15] Fast charging station for electric vehicles with at least one power module (3) according to claim 14.

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