Cooling system for electronic control units of a vehicle

Abstract

A cooling system for electronic control units of a vehicle is proposed, comprising a cooling housing and at least one control unit designed to control functions of the vehicle, wherein the cooling housing has an interior formed by wall elements, which is designed to accommodate the at least one control unit, and wherein a coolant is introduced into the interior, and wherein the at least one control unit has at least one printed circuit board, each of which is at least partially equipped with electronic components to be cooled, and wherein at least one connector pointing outwards is provided at at least one end region thereof, and wherein the at least one control unit is arranged in the cooling chamber such that the end regions of the printed circuit board with the connectors protrude outwards from the interior.

Description

[0001] The present invention relates to the field of cooling of control units of a vehicle.

[0002] As is well known, a vehicle contains several so-called electronic control units, also known as ECUs for short. These are used to process information that has been transmitted, for example, from sensors to the respective control unit as sensor data. Such electronic control units are formed as a combination of electronic components arranged on a circuit board that are electrically and / or signal-wise connected and can, for example, receive and process data from sensors and, based on the processing of the sensor data, control actuators. Electronic components include microcontrollers, SoCs (System on Chips), chiplets, coils, capacitors, etc. Electronic control units can perform a variety of tasks. They can be used, for example, to control entertainment functions or individual driving functions of the vehicle or even to control fully autonomous driving.

[0003] There is currently a trend towards combining multiple control units that perform different tasks into a central control unit. This is achieved by either combining the individual control units on a common circuit board or by using a so-called multi-board control unit, in which multiple control units (populated circuit boards) are arranged in parallel, i.e., they are no longer distributed at different positions in the vehicle. Such multi-board control units can also be used to execute functions that require high computing power, such as ADAS functions, i.e., functions for highly automated and even autonomous driving, or for entertainment functions. For control units with very high computing power, such as central control units, cooling is required to dissipate the generated heat flow and sufficiently cool the control unit's electronic components.

[0004] The most common method is traditional water cooling using pipes, although this is only of limited use in the field of control unit cooling. Therefore, so-called "cold plates" are used here, for example. These are essentially a single metal plate made of electrically non-conductive material that is positioned above the components to be cooled and mechanically (thermally conductively) contacted with them. The problem here is that tolerances between the metal plate and the components must be compensated for using a gap filler. However, since these gap fillers generally have poorer thermal conductivity than the metal plate, high thermal losses can occur, which impairs the cooling of the components.

[0005] Alternatively, single-chip cooling systems are already possible, in which a metal plate (also electrically non-conductive) serves as a heat sink for each component (chip) to be cooled. However, this is very complex to implement, as each component must be supplied with cooling water individually.

[0006] Another alternative are so-called microchannel evaporators, which feature a multitude of so-called µ-channels. These are also each applied to a separate chip, which in turn leads to the problem of individual cooling.

[0007] The invention is therefore based on the object of providing an improved cooling solution for control units in the automotive sector.

[0008] This problem is solved by the features of the independent claims. Advantageous embodiments are the subject of the dependent claims.

[0009] A cooling system for electronic control units of a vehicle is proposed, comprising a cooling housing and at least one control unit which is designed to control functions of the vehicle, wherein the cooling housing has an interior space formed by wall elements which is designed such that it can accommodate the at least one control unit, and wherein a cooling liquid is introduced into the interior space, and wherein the at least one control unit has at least one printed circuit board, each of which is at least partially equipped with electronic components to be cooled, and wherein at least one plug connector pointing outwards of the printed circuit board is provided on at least one end region thereof, and wherein the at least one control unit is arranged in the cooling space such that the end regions of the printed circuit board with the plug connectors protrude outside the interior space.

[0010] In one version, a circulation pump is arranged within the interior.

[0011] In one version, the circulation pump is connected to at least one control unit in terms of signaling and electrical connections.

[0012] In one embodiment, a connector housing is provided on the wall element from which the end regions protrude, which receives the end regions with the connectors and is designed to protect them from external influences and to serve as an interface for a mating connector.

[0013] In one embodiment, a passive cooling structure is arranged on at least one electronic component to be cooled.

[0014] In one embodiment, a heat exchanger is arranged in a thermally conductive manner on at least one wall element.

[0015] In one embodiment, the cooling fluid is an electrically non-conductive cooling fluid comprising oil. In one embodiment, the control unit is provided with an electrically insulating coating, and the cooling fluid is an electrically non-conductive or an electrically conductive cooling fluid.

[0016] In one embodiment, electronic components include microcontrollers, SoC, chiplets, inductors, capacitors, power semiconductors.

[0017] In one embodiment, at least two circuit boards are arranged in the interior, forming a central control unit.

[0018] In one embodiment, functions of the vehicle that are controlled by the at least one control unit are ADAS and / or entertainment functions.

[0019] Further features and advantages of the invention will become apparent from the following description of exemplary embodiments of the invention, with reference to the figures of the drawing, which illustrate details of the invention, and from the claims. The individual features can be implemented individually or in combination in a variant of the invention.

[0020] Preferred embodiments of the invention are explained in more detail below with reference to the accompanying drawings.

[0021] Fig. 1 shows a basic structure of a cooling system for electronic control units of a vehicle according to an embodiment of the present invention.

[0022] The following based on Fig. The cooling solution described in 1 provides an improved cooling solution for control units, especially central control units with high power and therefore required heat dissipation, in the automotive sector.

[0023] The cooling solution is designed as a cooling system in which one or more control units 2 are arranged in an interior space 11 of a cooling housing 10. For the sake of clarity, only one control unit 2 with multiple circuit boards 20 is shown below. However, only one circuit board 20 per control unit and more than one control unit 2 can be provided in the cooling housing 10.

[0024] The interior of the cooling housing 10 is formed by wall elements, which are generally provided as individual wall elements and can be connected to one another in a media-tight manner, which facilitates the introduction of components into the interior, e.g. the control unit 2 or a pump, etc. However, it can also be provided that the cooling housing 10 is at least partially manufactured in one piece and, for example, only the wall element through which the end regions of the circuit board(s) 20 protrude still needs to be attached (described below). The way in which the cooling housing 10 is provided and fully assembled depends on the specific construction and installation situation and is selected appropriately by a specialist. It is important that, after assembly, the cooling housing 10 seals the control unit 2 to the outside in a media-tight manner and that the connectors 22 protrude outside the cooling housing 10.

[0025] A control unit 2 consists of one or more printed circuit boards 20. These are equipped with several electronic components 21, for example microcontrollers, SoCs, chiplets, coils, capacitors, all of which must be cooled. At least one end region of at least one of the printed circuit boards 20 has at least one connector 22 pointing outwards of the printed circuit board 20 for electrical and / or signaling connection to the outside. At least one connector 22 can be provided per printed circuit board 20, or several printed circuit boards 20 can be connected to one another within the cooling housing 10, so that only one end region of a printed circuit board 20 needs to be led outwards of the cooling housing 10. This means that fewer connectors 22 are required that need to be led outwards of the cooling housing 10.

[0026] In order to guide a connector 22 to the outside of the cooling housing 10, an opening (preferably one opening per circuit board 20) is provided in a corresponding wall element, through which the circuit board 20 with the associated connector 22 protrudes outside the cooling housing 10 after assembly. This opening is sealed in a media-tight manner in an assembly step so that a cooling liquid 30 contained in the interior 11 of the cooling housing 10 cannot escape to the outside.

[0027] As mentioned, a cooling liquid 30 is filled into the interior 11 of the cooling housing 10. This is generally an electrically non-conductive liquid such as oil. However, if the control unit 2 (or parts thereof) is provided with an electrically insulating coating, the cooling liquid 30 can also be electrically conductive. The interior 11 can be filled before or after the control unit 2 is installed in the interior 11. A separate opening for filling the interior 11 can be provided, which is subsequently sealed in a media-tight manner. Alternatively, filling can take place via the side of the cooling housing 10, which serves to accommodate the control unit 2 and is therefore previously open.

[0028] Due to the expected thermal expansion of the coolant 30, it either does not completely fill the interior 11, or a separate tank connected to the interior 11 serves as a buffer (storage) into which the coolant can escape in the expanded state. Advantageously, it can leave this tank again in the deflated state. Since neither an inlet nor an outlet for the coolant 30 from the interior 11 is provided (it is media-tight), the system is thus closed.

[0029] Furthermore, a circulation pump 40 can be provided within the interior 11, as in Fig. 1. Advantageously, it is signal-connected to each control unit 2 in such a way that they can request that the circulation pump 40 be switched on and off, i.e., can control (and, if necessary, regulate) the circulation pump 40. Particularly advantageously, there is also an electrical connection via the control unit 2 for supplying the circulation pump 40 with electrical energy, so that no separate electrical line, which must be sealed separately, needs to be led into the interior 11. The circulation pump 40 is placed at a suitable location in the interior 11, i.e., on the one hand, at a location that is as flow-optimized as possible, and on the other hand, at a location where it can be connected to the control unit 2 as optimally as possible.

[0030] The printed circuit boards 20 of the control unit 2 can, for example, be attached to a holder (not shown) provided in the interior 11. This provides stability. If multiple printed circuit boards 20 are arranged in the interior 11, they are preferably arranged such that all connectors 22 face the same wall element, thus only requiring openings in one wall element for the end regions of the printed circuit board 20 to pass through. This also facilitates connection to mating connectors (not shown) with which the connectors 22 are contacted in order to receive electrical energy and to be able to conduct signals to and from the printed circuit board 20, depending on the application.

[0031] In one embodiment, the end regions of the circuit board 20 are surrounded by a connector housing 60 in which no cooling fluid 30 is present. The connector housing 60 protects the end regions and the electrical contacts from external influences. Only the electrical contacts (as pins or sockets) then protrude from the connector housing 60 to be connected to the corresponding mating contacts of a mating connector.

[0032] In the case where the components 21 to be cooled are provided only on one side of the circuit board 20, and multiple circuit boards 20 are provided, the circuit boards 20 can be arranged so that all components 21 to be cooled point in the same direction. In the case of two circuit boards 20, the components 21 to be cooled can also point away from each other, as shown in Fig.1. In a further embodiment, an additional (passive) cooling structure 50, e.g., in the form of pins or pin fins, can be arranged on one or more of the components 21 to be cooled in order to increase the surface area for heat dissipation.

[0033] A heat exchanger 70, well known in the art, is provided on at least one outer side of the cooling housing 10 and in contact with the respective wall element thereof (thermally conductive connection). This heat exchanger is connected to a cooling circuit of the vehicle and serves to dissipate the heat generated by the components 21 of the control unit 2 and released into the coolant 30 in the interior 11 of the cooling housing 10. Advantageously, the heat exchanger 70 is of course not provided on the wall element on which the connector housing 60 is provided, or on which the end regions with the connectors are provided, although this is not excluded.

[0034] The proposed cooling solution for vehicle control units, particularly those designed as central control units, such as a multi-board ADAS and / or infotainment ECU, reduces the complexity of the cooling system, as no piping or tolerance compensation between the chips is required. This also simplifies assembly. Furthermore, in the event of a water pump failure in the external cooling circuit, the proposed system still has sufficient capacity for short-term heat dissipation. This allows short-term operation even without a connected water circuit, e.g., for initial commissioning / maintenance / when the vehicle is stationary, etc. The temporarily continued cooling can also bring the vehicle into a safe state. The provided housing also provides EMC shielding. List of reference symbols 10 cooling housings 11 Interior 2 control unit 20 circuit board 21 electronic components 22 connectors 30 coolant 40 Circulation pump 50 Cooling structure 60 connector housings 70 heat exchangers

Claims

[1] Cooling system for electronic control units (2) of a vehicle, comprising a cooling housing (10) and at least one control unit (2) designed to control functions of the vehicle, wherein: - the cooling housing (10) has an interior space (11) formed by wall elements, which is formed in such a way that it can accommodate the at least one control device (2), and wherein a cooling liquid (30) is introduced into the interior space (11), and - the at least one control unit (2) has at least one printed circuit board (20), each of which is at least partially equipped with electronic components (21) to be cooled, and wherein at least one connector (22) pointing outwards from the printed circuit board (20) is provided on at least one end region thereof, and wherein - the at least one control device (2) is arranged in the cooling chamber (10) such that the end regions of the printed circuit board (20) with the plug connectors (22) protrude outside the interior space (11). [2] Cooling system according to claim 1, wherein a circulation pump (40) is arranged within the interior space (11). [3] Cooling system according to claim 2, wherein the circulation pump (40) is signal-technically and electrically connected to at least one control unit (2). [4] Cooling system according to one of the preceding claims, wherein a plug housing (60) is provided on the wall element from which the end regions protrude, which plug housing receives the end regions with the plug connectors (22) and is formed in such a way as to protect them from external influences and to serve as an interface for a mating plug connector. [5] Cooling system according to one of the preceding claims, wherein a passive cooling structure (50) is arranged on at least one electronic component (21) to be cooled. [6] Cooling system according to one of the preceding claims, wherein a heat exchanger (70) is arranged in a thermally conductive manner on at least one wall element. [7] Cooling system according to one of the preceding claims, wherein the cooling liquid (30) is an electrically non-conductive cooling liquid (30) comprising oil, or wherein the control unit (2) is provided with an electrically insulating coating and the cooling liquid (30) is an electrically non-conductive or an electrically conductive cooling liquid (30). [8] Cooling system according to one of the preceding claims, wherein electronic components (21) comprise: microcontrollers, SoC, chiplets, coils, capacitors, power semiconductors. [9] Cooling system according to one of the preceding claims, wherein at least two printed circuit boards (20) are arranged in the interior (11), which form a central control unit (2). [10] Cooling system according to one of the preceding claims, wherein functions of the vehicle which are controlled by the at least one control unit (2) are ADAS and / or entertainment functions.

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