Cooled electronics block with temperature sensor

Abstract

Cooled electronic block with temperature sensor, comprising an electronic module (1) containing a printed circuit board (12) equipped with electronic components (11) and a heat sink (3) with a planar contact area (31), wherein the printed circuit board (12) and the heat sink (3) are arranged relative to each other in such a way that they enclose together a cavity (32) filled with a filler material (33), which extends at least over the planar contact area (31) and in which the electronic components (11) are embedded, and a temperature sensor (2), wherein the temperature sensor (2) is also arranged in the filler material (33).

Description

[0001] The invention relates to a cooled electronics block with a temperature sensor.

[0002] Operating the electric drive components of hybrid or electric vehicles requires high electrical power. Accordingly, power electronic components are needed to control these drive components, and these are typically housed in an electronic control unit. It is known that these components, by their very nature, generate significant power losses, which must be dissipated as heat. To maintain the functionality of these components and prevent thermal overload, it is essential to provide a suitable cooling system within the electronic control unit to dissipate the heat quickly and efficiently.

[0003] Due to a good heat transfer coefficient, liquid cooling is particularly suitable for the effective removal of large amounts of heat, in which the cooling liquid circulates in a cooling circuit and the cooling liquid is brought into direct or indirect thermal contact with the power electronic components.

[0004] To better protect components against thermal overload under high stress, or to gain more precise control over cooling effectiveness, it is advisable to measure and monitor the coolant temperature using temperature sensors. A temperature sensor installed in the cooling circuit, which is in direct contact with the coolant to measure its temperature, requires an opening in one of the circuit's walls. This opening must then be sealed. The seal should remain stable over the long term, even under harsh conditions such as frequent temperature fluctuations or vibrations. Therefore, every opening in the cooling circuit also represents a potential source of leaks.In the event of leaks, the use of a liquid and therefore usually also electrically conductive cooling medium can always become problematic when the cooling fluid comes into contact with current-carrying components.

[0005] US 2016 / 0192472A1 discloses a cooled electronics block with a temperature sensor, comprising an electronics module containing a printed circuit board populated with electronic components and a heat sink with a planar contact area, wherein the printed circuit board and the heat sink are arranged relative to each other in such a way that they enclose a cavity filled with a filler material which extends at least over the planar contact area, and a temperature sensor, wherein the temperature sensor is also arranged in the filler material.

[0006] DE 10 2007 052 ​​630 B4 shows a power semiconductor module with an electrically and thermally conductive base plate, an electrically insulating and thermally conductive substrate arranged on the base plate, a metallization applied at least on the side of the substrate facing away from the base plate, at least one semiconductor device attached to the substrate and / or the metallization and electrically connected to the metallization, a housing which, together with the base plate, at least partially encloses the substrate and the at least one semiconductor device, and a temperature sensor at least partially enclosed by the housing and base plate, which is embedded in a block of an electrically insulating and thermally conductive material.

[0007] DE 10 2005 011 259 A1 relates to a heat sensor for absorbing heat from a component and for dissipating heat by means of a cooling fluid.

[0008] US 2015 / 0070836A1 discloses a system for cooling an integrated circuit in a computing device.

[0009] The object of the invention is therefore to find a way to provide a cooled electronic block with a temperature sensor where long-term stable sealing of the sensor is not required.

[0010] This task is solved by a cooled electronics block with a temperature sensor, comprising an electronics module consisting of a printed circuit board (PCB) populated with electronic components and a heat sink with a flat contact area. The PCB and the heat sink are arranged relative to each other such that they enclose a cavity filled with a filler material, which extends at least over the flat contact area and in which the electronic components are embedded. The electronics module also includes a temperature sensor, which is likewise arranged within the filler material.

[0011] In a first embodiment of the cooled gearbox block, it comprises a housing with a housing part that forms the cooling element. This housing part has a recess on its outer surface, and a cover plate is provided to conceal the recess, thus forming a cooling channel. An inlet and an outlet are connected to the cooling channel.

[0012] The filling material is advantageously thermally conductive.

[0013] It is thermally optimizing if the temperature sensor is attached to the circuit board.

[0014] It is also advantageous to position the temperature sensor as close as possible to the inlet.

[0015] It is advantageous if the temperature sensor has a signal-connected storage and processing unit that is designed to determine the temperature of a coolant guided in the heat sink based on a temperature detected by the temperature sensor.

[0016] A display unit that is connected to the storage and processing unit via a signal connection is particularly advantageous.

[0017] Even more advantageous is a control unit connected to the storage and computing unit, which regulates the flow of coolant through the cooling channel depending on a temperature detected by the temperature sensor.

[0018] The invention will now be explained in more detail using exemplary embodiments. The accompanying figure shows: Fig. 1. A basic structure of a cooled electronics block with a temperature sensor.

[0019] As in Fig.As shown in Figure 1, a cooled electronic block with a temperature sensor 2 comprises an electronic module 1 containing at least one printed circuit board 12 and electronic components 11 mounted on one or more printed circuit boards 12. The electronic block further comprises a heat sink 3. The heat sink 3 has a planar contact area 31 with a cavity 32, the cavity 32 extending at least over the planar contact area 31. The cavity 32 is filled with a filler material 33. The printed circuit board 12 and the heat sink 3 are arranged relative to each other such that they enclose the cavity 32 filled with the filler material 33. The electronic components 11 arranged on the printed circuit board 12 and the temperature sensor 2 are embedded within the cavity 32 in the filler material 33.

[0020] In the embodiment shown here, the heat sink 3 is a housing part 4 of a housing (not shown in the figures) in which at least the electronic module 1 is accommodated. The housing part 4 has a recess 41 on one outer surface 42. The recess 41 is covered by a cover plate 5, thereby forming a cooling channel 6 between the housing part 4 and the cover plate 5. An inlet 61 and an outlet 62 are arranged in the cover plate 6 to provide access to the cooling channel 6, via which the cooling channel 6 is connected to a cooling circuit (not shown in the figures).

[0021] Opposite the cooling channel 6, the planar contact area 31 is arranged on an inner surface 43 of the housing part 4. The electronic components 11 of the electronic module 1 are thermally coupled to the housing part 4 in the planar contact area 31.

[0022] The electronic module 1 is a printed circuit board that is at least partially populated with the temperature sensor 2 and the electronic components 11. The electronic components 11 include, for example, MOSFETs, IGBTs, or power capacitors, which, as components of power electronics, must dissipate high levels of power loss in the form of heat due to their function.

[0023] For thermal coupling of the electronic components 11, the thermal contact area 31 has at least one cavity 32 filled with the compound 33. The electronic components 11 are immersed in the cavity 32, so that the circuit board 12 covers the cavity 32. The cavity 32 is dimensioned such that the compound 33 forms the thinnest possible layer between the housing part 4 and the electronic components 11, thereby achieving optimal heat transfer to the housing part 4. The compound 33 is thermally conductive and therefore ensures a distribution of the heat across the entire surface area beyond the dimensions of the electronic components 11.

[0024] The temperature sensor 2 is also located in the cavity 32 and encapsulated in the filler material 33. The temperature sensor 2 is positioned as close as possible to the inlet 61. Due to its placement on the circuit board 12, the temperature sensor 2 is isolated from the cooling channel 5, so no separate seal is required.

[0025] Temperature sensor 2 determines the temperature of a cooling medium circulating in cooling channel 6. For this purpose, temperature sensor 2 is connected to a storage and processing unit (not shown). The storage and processing unit contains a simulation that calculates the actual temperature of the cooling medium from its indirectly measured temperature.

[0026] The temperature sensor 2 is used to determine the temperature of at least one electronic component 11. The storage and processing unit is used for this determination. Due to thermal conductivity within the filling mass 33, it is also possible to directly determine the temperature of at least one electronic component 11.

[0027] The flow of coolant through cooling channel 6 is regulated based on the calculated or determined temperatures. For this purpose, the storage and processing unit is connected to a control unit (not shown).

[0028] A display unit (not shown) is provided for outputting the temperature values; this unit is connected to the storage and processing unit via a signal connection. Reference sign 1 electronic module 11 electronic components 12 circuit boards 2 temperature sensors 3 heat sinks 31 Contact area 32 Cavity 33 Filling mass 4 Housing part 41 In-depth study 42 Outer surface of the housing part 43 Inside of the housing part 5. Closure plate 6 Cooling channel 61 Inflow 62 Procedure

Claims

[1] Cooled electronics block with temperature sensor, comprising an electronics module (1) containing a printed circuit board (12) equipped with electronic components (11) and a heat sink (3) with a flat contact area (31), wherein the printed circuit board (12) and the heat sink (3) are arranged relative to one another in such a way that they enclose a cavity (32) filled with a filling compound (33), which cavity extends at least over the flat contact area (31) and in which the electronic components (11) are embedded, and a temperature sensor (2), wherein the temperature sensor (2) is also arranged in the filling compound (33). [2] Cooled electronic block with temperature sensor according to claim 1, characterized bythat a housing is provided with a housing part (4) that forms the heat sink (3), wherein the housing part (4) has a recess (43) on an outer side (41) and a closure plate (5) covering the recess (43) is provided, whereby the recess (43), covered by the closure plate (5), forms a cooling channel (6) and an inlet (61) and an outlet (62) are provided, which are connected to the cooling channel (6). [3] Cooled electronic block with temperature sensor according to claim 1 or 2, characterized by that the filling material (33) is thermally conductive. [4] Cooled electronic block with temperature sensor according to one of the preceding claims, characterized by that the temperature sensor (2) is attached to the circuit board (12). [5] Cooled electronic block with temperature sensor according to one of the preceding claims, characterized bythat a storage and computing unit is provided which is signal-technically connected to the temperature sensor (2) and which is designed to determine a temperature of a coolant guided in the cooling body (3) on the basis of a temperature detected by the temperature sensor (2). [6] Cooled electronic block with temperature sensor according to claim 5, characterized by that the storage and computing unit is designed to determine a temperature of at least one of the electronic components (11) based on a temperature detected by the temperature sensor (2). [7] Cooled electronic block with temperature sensor according to claim 5 or 6, characterized by that a display unit is provided which is signal-connected to the storage and processing unit. [8] Cooled electronic block with temperature sensor according to claim 5, 6 or 7, characterized bythat a control unit is provided which is connected to the storage and computing unit and which regulates the flow of the coolant through the cooling channel (6) as a function of a temperature detected by the temperature sensor (2).

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