Cooling arrangement for a controller of a motor vehicle, and motor vehicle

Abstract

The invention relates to a cooling arrangement (1) for a controller (2) of a motor vehicle, comprising a cooling body (5) and comprising a latent heat store (10), wherein the cooling body (5) has at least one coolant channel (7) for a coolant which can be conveyed through the at least one coolant channel (7) for the purpose of dissipating heat, wherein the latent heat store (10) has at least one chamber (14, 15) containing a phase-change material (12). Provision is made for the cooling body (5) to be directly thermally coupled to the controller (2).

Description

[0001] Description

[0002] Cooling arrangement for a control unit of a motor vehicle, motor vehicle

[0003] The present invention relates to a cooling arrangement for a control unit of a motor vehicle, comprising a heat sink and a latent heat accumulator, wherein the heat sink has at least one coolant channel for a particularly liquid and / or gaseous coolant, which can be conveyed through the at least one coolant channel to dissipate heat, wherein the latent heat accumulator has at least one chamber with a phase change material.

[0004] The motor vehicle according to the invention with the features of claim 13 is characterized by the above-mentioned cooling arrangement.

[0005] Cooling arrangements of the type mentioned above are known from the prior art. For example, the published patent application DE 102016202 750 A1 discloses a cooling device for cooling a control unit for a motor vehicle. The cooling device comprises a heat sink through which a coolant can flow, as well as a latent heat accumulator that is or can be thermally coupled to the control unit on the one hand and the heat sink on the other. It is proposed that the latent heat accumulator be arranged between the heat sink and the control unit.

[0006] Further cooling arrangements are known, for example, from published patent applications DE 102017218 896 A1, US 8,937,384 B2, and DE 101 14 998 A1. In particular, the use of phase-change material in a latent heat storage device is already apparent from the above-mentioned publications.

[0007] Due to the thermal behavior of control units and their individual components, such as electronic chips, processing units, or the like, different thermal time constants arise within the control unit, which often requires energy-intensive cooling. The use of phase-change material in such a cooling arrangement ensures that the thermal time constants of the components to be cooled are thermally adapted. This allows for advantageous heat dissipation from the control unit even when no coolant is being pumped through the coolant channel of the heat sink. This can reduce the frequency of coolant demand and increase the energy efficiency of the cooling arrangement.The present invention is based on the object of creating an improved cooling arrangement which enables particularly efficient cooling of the control unit and, in particular, reliably protects the control unit from overheating in the event of a failure of a coolant system by means of which the coolant can be conveyed through the heat sink and / or in the event of short-term high power demands on the control unit.

[0008] The object underlying the invention is achieved by a cooling arrangement having the features of claim 1. This has the advantage that the phase change material is stressed less frequently during normal operation and thus enables very fast response times of the cooling system to stresses on the control unit, even when required. At the same time, the inventive design of the cooling arrangement ensures that in the event of an unexpected failure of the coolant system or the occurrence of unexpectedly high loads on the control unit, the control unit is still reliably protected from overheating. According to the invention, this is achieved in that the heat sink is directly thermally coupled to the control unit, i.e., it rests directly on the control unit or parts thereof, in particular on a circuit board of the control unit. By directly coupling the heat sink to the control unit, direct heat dissipation from the control unit by means of the coolant can be achieved when required.This means there's no latent heat storage between the heat sink and the control unit, which could delay heat transfer. Nevertheless, the phase-change material is present and indirectly thermally coupled to the control unit, so that if necessary—for example, if a coolant supply system fails—heat can be transferred from the control unit through the heat sink into the phase-change material to protect the control unit.

[0009] Preferably, the heat sink is thermally coupled to the latent heat storage device on a first side and is thermally coupled or can be thermally coupled to the control unit on a second side facing away from the first side. Thus, the heat sink is located completely between the latent heat storage device and the control unit, meaning that heat from the control unit can only reach the latent heat storage device through the heat sink. This ensures a simple and cost-effective design.

[0010] According to a preferred development of the invention, the latent heat accumulator has a contact wall that lies flat against a contact wall of the heat sink, so that the phase-change material lies on the side of the heat sink facing away from the control unit. The flat contact of the latent heat accumulator in the heat sink results in advantageous heat transfer from the heat sink to the latent heat accumulator. Optionally, a thermally conductive material, such as a thermal paste or the like, is arranged between the contact walls to further optimize heat transfer or reduce or minimize the heat transfer resistance from the heat sink to the latent heat accumulator.

[0011] According to a further embodiment of the invention, at least one chamber of the latent heat storage device, which is filled with phase-change material, is preferably arranged in the heat sink. As a result, the latent heat storage device is at least partially integrated into the heat sink of the cooling arrangement. This ensures a particularly advantageous heat transfer from the heat sink to the phase-change material. Preferably, several chambers of the latent heat storage device, each filled with phase-change material, are arranged in the heat sink.

[0012] According to a preferred development of the invention, several coolant channel sections of the one or more coolant channels run parallel and spaced apart from one another through the heat sink. The heat sink is thus penetrated by the coolant channels or by at least one coolant channel with several coolant channel sections running parallel to one another, ensuring that a large amount of heat can be dissipated in a short time. Preferably, the coolant channels or coolant channel sections run parallel to one another, ensuring uniform heat dissipation through the heat sink. In particular, the coolant channels run parallel to one another and parallel to the contact wall of the heat sink or to the control unit.

[0013] Preferably, a chamber of the latent heat storage device containing phase-change material is arranged between at least two adjacent coolant channel sections. This places the phase-change material between the coolant channel sections, ensuring advantageous heat dissipation into the phase-change material even when no coolant is being conveyed through the respective coolant channel section.

[0014] Furthermore, it is preferably provided that a chamber of the latent heat storage device containing phase change material is arranged between each two adjacent coolant channel sections. This also assigns a chamber containing phase change material to each coolant channel section, ensuring uniform heat dissipation from the control unit through the heat sink at all times.

[0015] Particularly preferably, the chamber or the respective chamber of the latent heat storage device extends in a channel-like manner parallel to a coolant channel section, thereby ensuring advantageous heat transfer from the phase-change material, for example, into the coolant conveyed through the respective coolant channel section, in order to be able to advantageously and quickly regenerate the phase-change material to its initial state after exposure. Furthermore, the channel-shaped design increases or maximizes the space for the phase-change material, so that a sufficient amount of phase-change material can be stored in the heat sink.

[0016] Preferably, one end face of the heat sink is designed to bear directly against the control unit, in particular against the circuit board. Particularly preferably, the end face extends at least substantially parallel to the contact wall of the heat sink associated with the latent heat storage device.

[0017] Furthermore, it is preferably provided that at least one chamber of the latent heat storage device is located in the heat sink between the end face of the heat sink and at least one coolant channel section. As a result, phase material is located between at least one coolant channel section and the control unit during intended use of the cooling arrangement, thereby ensuring advantageous and rapid heat dissipation of a phase-change material at this location. Alternatively, the chamber is preferably located between the coolant channel or coolant channel section and the contact wall of the heat sink.

[0018] Particularly preferably, one chamber extends parallel to the contact wall or the end face of the heat sink between the coolant channel and the contact wall or end face of the heat sink, thereby ensuring uniform heat dissipation of a phase change material.

[0019] Furthermore, it is preferably provided that the contact wall of the heat sink is designed to directly abut a circuit board of the control unit. For this purpose, the contact wall is designed, for example, to partially or completely accommodate the circuit board to enable advantageous heat dissipation.

[0020] Furthermore, it is preferably provided that the coolant channel is connected to at least one coolant conveying device of a cooling circuit, by means of which coolant can then be actively conveyed through the respective coolant channel as needed. By controlling the coolant conveying device, the control unit itself can be cooled, and the phase-change material of the latent heat storage device can be returned to its initial state or regenerated.

[0021] The motor vehicle according to the invention with the features of claim 13 is characterized by the inventive design of the cooling arrangement. This results in the advantages already mentioned above. Further advantages and preferred features and combinations of features emerge in particular from the above description and from the claims. The invention will be explained in more detail below with reference to the drawings.

[0022] Figure 1 shows a first embodiment of an advantageous cooling arrangement,

[0023] Figure 2 shows a second embodiment of the cooling arrangement,

[0024] Figure 3 shows a third embodiment of the cooling arrangement,

[0025] Figure 4 shows a fourth embodiment of the cooling arrangement,

[0026] Figure 5 shows a fifth embodiment of the cooling arrangement and

[0027] Figure 6 shows a sixth embodiment of the cooling arrangement, each in a simplified sectional view.

[0028] Figure 1 shows a simplified sectional view of an advantageous cooling arrangement 1 for a motor vehicle (not shown in detail here), which has a control unit 2. The control unit 2, which in particular forms a component of the cooling arrangement 1, has in particular a carrier substrate in the form of a printed circuit board 3, on which a plurality of electrical / electronic components 4 are arranged, which are designed, for example, as switching modules, such as semiconductor switching elements, electrical storage elements, computing units, microchips, control units and / or sensor units. The control unit 2 is assigned a heat sink 5, which is made of a material with high thermal conductivity. The heat sink 5 has an end face 6, which lies flat against the control unit 2, in particular against the printed circuit board 3.Optionally, a thermal paste or the like is arranged between the contact wall 6 and the circuit board 3 in order to ensure advantageous heat transfer from the circuit board to the heat sink 5.

[0029] The heat sink 5 is provided with one or more coolant channels 7 that extend through the heat sink 5. A plurality of coolant channel sections 8 of the one or more coolant channels run parallel to one another through the heat sink 5, as shown in Figure 1, wherein the coolant channel sections 8 are formed in the heat sink 5 so as to be distributed uniformly in relation to the distance between adjacent coolant channel sections 8. The at least one coolant channel 7 is fluidly connectable or connected to a coolant delivery system, such that a coolant can be conveyed through the coolant channel 7 or the coolant channels 7 by the coolant delivery system.

[0030] In particular, the coolant delivery system comprises a device for cooling the coolant or for regenerating the coolant, so that the coolant supplied to the cooling arrangement 1 is capable of dissipating the heat that was conducted from the control unit 2 into the heat sink 5 from the heat sink 5. In particular, the coolant is a liquid and / or gaseous coolant.

[0031] The heat sink 5 further has, on its side facing away from the control unit 2, a contact wall 9, to which a latent heat accumulator 10 is assigned. The latent heat accumulator 10 has a housing 11 in which a phase-change material 12 is arranged. The housing 11 has a contact wall 13 facing the heat sink 5, wherein the contact walls 9 and 13 are designed to bear flatly against one another in order to ensure advantageous heat transfer with low heat transfer resistance between the heat sink 5 and the latent heat accumulator 10. Optionally, a thermally conductive paste or the like is arranged between the latent heat accumulator 10 and the heat sink 5, by means of which the heat transfer is optimized.

[0032] The phase change material is in particular a wax material, in particular based on paraffin, and has, for example, a preferred melting range of approximately 69°, so that when the melting range is exceeded, it undergoes a phase change due to the heat loss of the components of the control unit 2 to be protected and thereby absorbs and stores heat.

[0033] According to the exemplary embodiment of Figure 1, the heat sink 5 is located between the latent heat accumulator 10 and the control unit 2. The heat sink 5 and the coolant channel 7 ensure active thermal management of the control unit, through which, for example, more or less coolant is pumped through the coolant line 7 depending on the current temperature of the control unit 2. If the coolant delivery system fails, the heat is no longer dissipated by the coolant. The phase change material 12 has a defined melting point or range, as already mentioned above. The heat that is not dissipated by the coolant thus increasingly enters the latent heat accumulator and leads to the material reaching its melting point due to the increasing heat and, upon reaching its melting point, advantageously absorbing the heat.The heat generated by the control unit 2 and no longer dissipated by the coolant system is thus absorbed and (temporarily) stored by the latent heat storage device. This ensures that the components 4 of the control unit 2 do not overheat, and in particular, do not overheat beyond a predetermined period of time, thereby delaying derating, i.e., a decline in the performance of the control unit 2. Thus, the phase-change material 12 can also advantageously absorb temperature peaks of the control unit 2 during normal operation of the coolant supply system.

[0034] First and foremost, however, the advantageous cooling arrangement 1 ensures that, in the event of a failure of the coolant system, the control unit 2 can continue to operate for a predetermined period of time without its performance having to be restricted to protect the components. This makes the cooling arrangement 1 particularly suitable for control units used in the field of autonomous driving. The advantageous cooling arrangement 1 can ensure that, after the coolant supply system has been selected, the motor vehicle can still be brought into a safe state, for example, into a parked position on the hard shoulder of a motorway or the like, by the autonomous driving operation of the control unit 2, before there is a risk of overheating of the control unit 2 and its performance having to be reduced.The advantageous cooling arrangement thus delays a failure or a reduction in the operability of the control unit 2, thereby increasing the driving safety of the motor vehicle. Since the heat sink 5 is located between the latent heat accumulator 10 and the control unit 2, it is normally ensured that the latent heat accumulator is little affected or impaired by the heat, and rather, the heat can be dissipated directly by the coolant. This also ensures that the coolant delivery system can be quickly adjusted depending on the operating temperature of the control unit 2 in order to dissipate more or less heat. This ensures particularly efficient operation of the cooling arrangement and the control unit as a whole.

[0035] Figure 2 shows a further embodiment of the cooling arrangement 1. In Figure 2 and the following figures, elements already known from Figure 1 are provided with the same reference numerals, so reference is made to the above description in this regard. In the following, only the differences will be discussed.

[0036] In contrast to the first exemplary embodiment, in the exemplary embodiment of Figure 2, the latent heat accumulator 10 is designed to be integrated directly into the heat sink 5. For this purpose, the heat sink 5 has a plurality of chambers 14 with phase change material 12 located therein, which chambers are located between two adjacent coolant channel sections 8. In particular, the respective chamber 14 extends parallel to the respective coolant channel section 8 through the heat sink 5. Optionally, the chambers 14 are partially fluidically connected to one another, so that the chambers 14 also form one or more channels in the heat sink 5. By integrating the chambers 14 or the latent heat accumulator 10 into the heat sink 5, a particularly compact embodiment of the cooling arrangement 1 is created, and a rapid response of the latent heat accumulator 10 is achieved in the event that the coolant system fails.In this case, the heat transfer path from the control unit 2 to the latent heat storage device 10 is particularly short, so that faster heat dissipation is ensured in the event of a fault in the coolant supply system.

[0037] According to the embodiment of Figure 3, the latent heat accumulator 10 is also integrated into the heat sink 5, wherein, in addition to the chambers 14 between the adjacent coolant channel sections 8, a further chamber 15 with phase change material 12 is present, which extends parallel to the contact wall 6 on the side facing away from the circuit board 3 or the contact wall 6 of the heat sink 5. This forms a chamber 15 which almost corresponds to the latent heat accumulator 10 from the first embodiment 1, with the difference that the chamber 15 is directly integrated into the heat sink 5 and the chambers 14 are additionally present between adjacent coolant channel sections 8.Due to the additional chamber 15 with phase change material 12, the storage capacity of the latent heat storage device 10 is advantageously increased compared to the embodiment of Figure 2, whereby the time delay before the performance of the control unit 2 must be restricted in order to ensure component protection is increased.

[0038] The embodiment shown in Figure 4 differs from the embodiment of Figure 3 in that the chamber 15 is located between the coolant channel sections 8 and the contact wall 6 of the heat sink 5 in the heat sink 5. This ensures a particularly rapid response of the latent heat accumulator 10.

[0039] According to the embodiment of Figure 5, in contrast to the embodiment of Figure 4, only the chamber 15 of the latent heat accumulator 10 is provided, but the chambers 14 between the adjacent coolant channel sections 8 are omitted. This allows the latent heat accumulator 10 to be structurally simpler and thus more cost-effectively integrated into the heat sink 5.

[0040] Figure 6 shows a further embodiment of the cooling arrangement 1, which differs from the embodiment of Figure 5 in that the chamber 15 is not located on the side of the heat sink 5 facing towards the control unit 2, but rather on the side facing away from the control unit 2. In this respect, this arrangement corresponds almost identically to the arrangement of Figure 1, but with the difference that the latent heat accumulator 10 is not designed as a separate component, but is integrated directly into the heat sink 5. This results in improved thermal conductivity due to reduced thermal resistance. In particular, the chamber 15 has a width and length that at least substantially corresponds to the width and length of the printed circuit board 3, with the height of the chamber 15, and thus the filling volume of the chamber 15 with phase change material 12, depending in particular on the desired performance of the latent heat accumulator.

Claims

Patent claims 1. Cooling arrangement (1) for a control unit (2) of a motor vehicle, with a heat sink (5) and with a latent heat accumulator (10), wherein the heat sink 5() has at least one coolant channel (7) for a coolant which can be conveyed through the at least one coolant channel (7) to dissipate heat, wherein the latent heat accumulator (10) has at least one chamber (14, 15) with a phase change material (12), characterized in that the heat sink (5) is directly thermally coupled to the control unit (2).

2. Cooling arrangement according to claim 1, characterized in that the cooling body (5) is thermally coupled to the latent heat accumulator (10) on a first side and can be or is thermally coupled to the control unit (2) on a second side facing away from the first side.

3. Cooling arrangement according to one of the preceding claims, characterized in that the latent heat storage device has a contact wall (13) which lies flat against a contact wall (9) of the heat sink (5), so that the phase change material (12) lies on the side of the heat sink (5) facing away from the control device (2).

4. Cooling arrangement according to one of the preceding claims, characterized in that at least one chamber (14, 15) of the latent heat storage device, which is filled with phase change material, is arranged in the cooling body (5).

5. Cooling arrangement according to one of the preceding claims, characterized in that several coolant channel sections (8) of the one or more coolant channels (7) run parallel and spaced from one another through the cooling body (5).

6. Cooling arrangement according to one of the preceding claims, characterized in that a chamber (14) of the latent heat accumulator (10) with phase change material (12) is arranged between at least two adjacent coolant channel sections (8).

7. Cooling arrangement according to one of the preceding claims, characterized in that a chamber (14) of the latent heat accumulator (10) with phase change material (12) is arranged between each two adjacent coolant channel sections (8).

8. Cooling arrangement according to one of the preceding claims, characterized in that the respective chamber (14) of the latent heat accumulator (10) extends parallel to a coolant channel section (8).

9. Cooling arrangement according to one of the preceding claims, characterized in that an end face (6) of the heat sink (5) is designed to bear directly against the control unit (2), in particular against the printed circuit board (3).

10. Cooling arrangement according to one of the preceding claims, characterized in that at least one chamber (15) of the latent heat accumulator (10) in the heat sink (5) is located between the end face (6) or the contact wall (9) of the heat sink (5) and at least one coolant channel section (8).

11. Cooling arrangement according to claim 9, characterized in that the at least one chamber (15) extends parallel to the end face (6) or contact wall (9) of the heat sink (5) between the coolant channel (7) and the end face (6) or contact wall (9) of the heat sink (5).

12. Cooling arrangement according to one of the preceding claims, characterized in that the coolant channel (7) is or can be connected to at least one coolant conveying device of a cooling circuit.

13. Motor vehicle with at least one control unit (2), which is designed in particular to carry out at least one automatic or autonomous driving function, and with a cooling arrangement (1) assigned to the control unit (2), characterized by the design of the cooling arrangement (1) according to one of claims 1 to 12.

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