High-voltage power box for an electrically driven vehicle

Abstract

The invention relates to a high-voltage power box (1) for an electrically driven vehicle, having a housing (2) with components (11, 13, 15), which are arranged therein, of a DC-to-DC converter and components (11, 13, 15) of an onboard charger, wherein power components (11) of both the DC-to-DC converter and the onboard charger are arranged on a first substrate (10), and control components (13) of both the DC-to-DC converter and the onboard charger are arranged on a second substrate (12).

Description

[0001] High-voltage box for an electrically powered vehicle

[0002] Description

[0003] The present invention relates to a high-voltage box for an electrically powered vehicle, comprising a housing with components of a DC-DC converter and components of an on-board charger arranged therein.

[0004] High-voltage boxes are installed in electrically powered vehicles. These boxes primarily contain a DC-DC converter for providing low voltage for the 12 V electrical system, as well as an on-board charger that charges the vehicle's high-voltage battery with mains voltage. These components are housed in a housing typically made of die-cast aluminum.

[0005] Since power components can exhibit high power losses during operation, effective cooling is required. A liquid cooler is often provided for this purpose. This can be located centrally within the housing, allowing both its top and bottom surfaces to be used for mounting power components. The liquid cooler is made of die-cast aluminum and exhibits very good thermal conductivity. A coolant, such as water, flows through it during operation. Typically, the DC-DC converter components are located on the bottom of the liquid cooler, and the on-board charger components on the top.

[0006] There is a need to further save space and weight of devices and assemblies in the vehicle, including the high-voltage box.

[0007] It is therefore an object of the present invention to provide a high-voltage box for an electrically powered vehicle that is particularly compact and lightweight. This object is achieved by the subject matter of the independent patent claim. Advantageous embodiments and further developments are the subject matter of the dependent claims.

[0008] According to one aspect of the invention, a high-voltage box for an electrically powered vehicle is provided, comprising a housing with components of a DC-DC converter and components of an on-board charger arranged therein. Power components of both the DC-DC converter and the on-board charger are arranged on a first substrate arranged within the housing. Control components of both the DC-DC converter and the on-board charger are arranged on a second substrate within the housing.

[0009] Accordingly, components in the high-voltage box are not grouped separately according to their functional assemblies (on-board charger or DC-DC converter), but rather the components are grouped according to other criteria, in particular by component type and power loss during operation. Thus, the power components of the DC-DC converter and the on-board charger are arranged on a common power substrate (common power board), while the control components of the DC-DC converter and the on-board charger are arranged on a common control substrate (common control board). In particular, all power components of the DC-DC converter and the on-board charger can be arranged together on the first substrate, and all control components of the DC-DC converter and the on-board charger are arranged together on the second substrate.

[0010] This has the advantage of reducing the number of required substrates. Furthermore, the number of power and signal connections and the length of electrical connections between the control substrate and the power substrate are reduced. Another advantage is lower production costs, since only two or three substrates need to be assembled and connected. According to one embodiment, the components on the first substrate are connected using SMD (surface-mounted device) technology. The components on the second substrate can, in particular, also be connected using SMD technology.

[0011] According to one embodiment, a liquid cooler is arranged in the housing, wherein the first substrate is arranged immediately adjacent to a main surface of the liquid cooler and the second substrate is arranged at a distance from the main surface of the liquid cooler.

[0012] This embodiment has the advantage that the power substrate, whose components have increased cooling requirements, can be arranged directly on the liquid cooler and thus cooled particularly effectively. The control components arranged on the second substrate have lower cooling requirements and therefore do not need to be arranged directly on the liquid cooler.

[0013] Such an arrangement has the additional advantage that electromechanical components of both the DC-DC converter and the on-board charger arranged on a third substrate can be arranged on the still free main surface of the liquid cooler and can thus also be optimally cooled.

[0014] According to one embodiment, electromechanical components of both the DC-DC converter and the on-board charger, in particular transformers, chokes, and DC link capacitors, are arranged on a third substrate. The electromechanical components are therefore not arranged according to the functional assembly to which they are assigned, but rather according to their component type and thus also their cooling requirements.

[0015] According to one embodiment, the components are connected to the third substrate using THT (through-hole technology). THT technology is common and proven for electromechanical components. Alternatively, an overmolded lead frame can be used as the substrate, and the components can be connected to the substrate using laser welding.

[0016] The arrangement of power components, control components and electromechanical components on separate substrates has the further advantage that only one main connection technology is used for each substrate, which considerably simplifies the manufacturing process.

[0017] According to one embodiment, a liquid cooler is arranged in the housing, which has a base plate with a first main surface and a second main surface, and a cooling channel plate made of a deep-drawn sheet metal and having a first main surface and a second main surface, arranged adjacent to the second main surface of the base plate, wherein the deep-drawn sheet metal and / or the base plate are shaped such that cooling channels are formed in the deep-drawn sheet metal between the first main surface of the cooling channel unit and the second main surface of the base plate. In particular, the cooling channels can be formed in a deep-drawing process in the deep-drawn sheet metal and / or the base plate. The second substrate is in thermal contact with the second main surface of the cooling channel plate and is in particular arranged directly on the second main surface.

[0018] This design offers the advantage of providing particularly effective yet space-saving cooling of the power components. Constructing the liquid cooler from deep-drawn sheet metal instead of a die-cast cooler offers the advantage of saving both weight and installation space due to the thinner material.

[0019] According to one embodiment, the second substrate is supported on the liquid cooler via bushings and / or bolts. In this embodiment, several substrates with components arranged thereon are stacked within the housing of the high-voltage box, wherein the second substrate is not arranged on the liquid cooler, but is supported on the liquid cooler via bushings and / or bolts. The second substrate thus leaves space on the main surface of the liquid cooler for the arrangement of components with higher cooling requirements.

[0020] In particular, it is advantageous if sockets or bolts are positioned so that they extend through the liquid cooler and secure all circuit boards in one position. This allows the number of required sockets or bolts to be kept to a minimum.

[0021] According to one embodiment, the base plate has a thickness D of 1.5 mm < D < 4 mm, and the cooling channel unit has a material thickness d of 0.5 mm < d < 2 mm. In particular, the thickness D can be approximately 3 mm and the thickness d 1.5 mm.

[0022] Such dimensions are easy to produce using common deep drawing processes and provide good heat transfer, and the relatively small thicknesses D, d allow weight savings to be achieved.

[0023] According to one embodiment, turbulators made of aluminum sheet are arranged in the cooling channels. These turbulators ensure a turbulent flow of the coolant through the cooling channels and thus particularly good heat dissipation. The turbulators can be arranged in particular in areas of the cooling channels where a particularly high heat input occurs due to the power components arranged therein.

[0024] The turbulators can, in particular, be structures made of strips of aluminum sheet metal that have been deep-drawn into a suitable shape, for example, a wave shape. They can be connected to the cooling channel unit and / or the base plate by a brazing process. Embodiments of the invention are described below by way of example with reference to schematic drawings.

[0025] Figure 1 shows an exploded view of a high-voltage box according to an embodiment of the invention;

[0026] Figure 2 shows a view of a liquid cooler of the high-voltage box according to Figure 1 from a first side;

[0027] Figure 3 shows a view of the liquid cooler according to Figure 2 from a second side and

[0028] Figure 4 shows a section through the high-voltage box according to Figure 1 .

[0029] The high-voltage box 1 according to Figure 1 has a housing 2 with an upper housing part 3 and a lower housing part 4. Components of a DC-DC converter and an on-board charger are arranged in the housing 2. The components are arranged on several substrates. Components 11, designed as power components, of both the DC-DC converter and the on-board charger are arranged on a first substrate 10. The first substrate 10 is arranged directly adjacent to a liquid cooler 25, since the components 11 have an increased cooling requirement due to their high power loss. The first substrate 10 can, in particular, be in direct thermal contact with the liquid cooler 25.

[0030] Control components of both the DC-DC converter and the on-board charger are arranged on a second substrate 12. These components do not require increased cooling, so the second substrate 12 can be arranged at a distance from the liquid cooler 25. The first substrate 10 and the second substrate 12 form a stack, with the first substrate 10 facing the liquid cooler 25. The second substrate 12 is supported on the liquid cooler 25 and / or the housing 2 by means of bolts 20 or bushings. The control components arranged on the second substrate 12 are shown in the illustration in Figure 1.

[0031] The high-voltage box 1 according to Figure 1 also has a third substrate 14, which is arranged on the other side of the liquid cooler 25. Electromechanical components of both the DC-DC converter and the on-board charger, such as transformers, chokes, or capacitors, are arranged on the third substrate 14. These components are relatively heavy and are contacted using THT technology.

[0032] The components on the first substrate 10 and on the second substrate 12 are contacted using SMD technology.

[0033] Figure 2 shows a top view of the high-voltage box 1, but with the upper housing section 3 removed. This illustration shows a first main surface 23 of the liquid cooler 25, which is formed as the upper side of a base plate 26 made of metal (sheet metal or die-cast). The electromechanical components 15 of the DC-DC converter and the on-board charger are arranged on this first main surface 23. They are contacted via a THT substrate 14.

[0034] Figure 3 shows a view of the high-voltage box 1 from below, but with the lower housing section 4 removed. This shows a second main surface 24 of the liquid cooler 25, which in this specific example is formed partly by the exposed base plate 26 and partly by a cooling channel plate 27. The cooling channel plate 27 can, in particular, be formed as a deep-drawn sheet and connected to the base plate 26 by brazing. Cooling channels (not shown in Figure 3) are formed between the cooling channel plate 27 and the base plate 26. The first substrate 10, on which the components 11 of the DC-DC converter and the on-board charger, designed as power components, are arranged, is designed as an SMD substrate and is in direct contact with the cooling channel plate 27, at least in some areas with particularly high heat loss.

[0035] The second substrate 12, which is also designed as an SMD substrate, has control components of both the DC-DC converter and the on-board charger and, in the embodiment shown in Figure 3, is less extensive than the first substrate 10.

[0036] Figure 4 shows a sectional view of the high-voltage box 1. In the sectional view, it can be seen that the first substrate 10 with the (power) components 11 designed as power semiconductor components, the second substrate 12 with (control) components 13 designed as control components, and the third substrate 14 with the electromechanical components 15 are stacked one above the other, wherein the first substrate 10 and the second substrate 12 are arranged below the liquid cooler 25 and the third substrate 14 above the liquid cooler 25. The second substrate 12 and the third substrate 14 are supported on the liquid cooler 25 by means of bolts 20 or bushings.

[0037] The liquid cooler 25 has the base plate 26 with its first main surface 23 and its second main surface 24 opposite the first main surface 23. Adjacent to the second main surface 24 of the base plate 26 is a cooling channel plate 27 made of deep-drawn sheet metal with a first main surface 29 facing the base plate 26 and a second main surface 30. The deep-drawn sheet metal of the cooling channel plate 27 is shaped such that cooling channels 28 are formed between the first main surface 29 of the cooling channel plate 27 and the second main surface 24 of the base plate 26.

[0038] Turbulators (not shown) are provided in the cooling channels 28 to introduce turbulence into the coolant and improve heat transfer. In the areas of the cooling channels 28, the first substrate 10 is in direct thermal contact with the cooling channel plate 27. The cooling channel plate 27 is connected to the base plate 26 by a brazing process. Brazing can be performed, in particular, in a brazing furnace. In this process, the turbulators 19 can also be brazed to the cooling channel unit 7 and / or the base plate 26.

Claims

Patent claims 1. A high-voltage box (1) for an electrically powered vehicle, comprising a housing (2) with components (11, 13, 15) of a DC-DC converter and components (11, 13, 15) of an on-board charger arranged therein; wherein power components (11) of both the DC-DC converter and the on-board charger are arranged on a first substrate (10), and control components (13) of both the DC-DC converter and the on-board charger are arranged on a second substrate (12).

2. High-voltage box (1) according to claim 1, wherein the components (11) on the first substrate (10) are connected by means of SMD technology.

3. High-voltage box (1) according to claim 1 or 2, wherein the components (13) on the second substrate (12) are connected by means of SMD technology.

4. High-voltage box (1) according to one of claims 1 to 3, wherein a liquid cooler (25) is arranged in the housing (2), wherein the first substrate (10) is arranged directly adjacent to a main surface (24) of the liquid cooler (25) and the second substrate (12) is arranged at a distance from the main surface (24) of the liquid cooler (25).

5. High-voltage box (1) according to one of claims 1 to 4, wherein electromechanical components (15) of both the DC-DC converter and the on-board charger are arranged on a third substrate (14).

6. High-voltage box (1) according to claim 5, wherein the electromechanical components (15) are connected to the third substrate (14) by means of THT technology or by means of laser welding.

7. High-voltage box (1) according to claim 5 or 6, wherein a liquid cooler (25) is arranged in the housing (2), wherein the third substrate (14) is arranged directly adjacent to a main surface (23) of the liquid cooler (25).

8. High-voltage box (1) according to one of claims 1 to 7, wherein a liquid cooler (25) is arranged in the housing (2), comprising - a base plate (26) having a first main surface (23) and a second main surface (24) opposite the first main surface (23), and - a cooling channel plate (27) arranged adjacent to the second main surface (24) of the base plate (26) and made of a deep-drawn sheet having a first main surface (29) and a second main surface (30), wherein the deep-drawn sheet and / or the base plate (26) are shaped such that cooling channels (28) are formed between the first main surface (29) of the cooling channel plate (27) and the second main surface (24) of the base plate (26), and wherein the first substrate (10) is in thermal contact with the second main surface of the cooling channel plate (27).

9. High-voltage box (1) according to claim 3, wherein the second substrate (12) is supported on the liquid cooler via bushings and / or bolts (20).

10. High-voltage box according to claim 9, wherein bushings and / or bolts (20) are positioned such that they extend through the liquid cooler (25) and fix substrates (10, 12, 14) below and above the liquid cooler (25) together in one position. 11 . Electrically powered vehicle with a high-voltage box (1) according to one of claims 1 to 10.

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