Heat dissipation structure

Abstract

The utility model belongs to the technical field of semiconductor heat dissipation, and provides a heat dissipation structure for heat dissipation of a power module, which comprises a pin fin and a heat dissipation part, the pin fin comprises a substrate and a bulge arranged on the substrate, and the substrate is arranged on the heat dissipation surface of the power module; the heat dissipation part is provided with a liquid flow channel used for conveying cooling liquid and is connected to the side, away from the power module, of the substrate in a sealed mode so that the heat dissipation part and the substrate can be spliced to form a heat dissipation cavity used for containing the protrusions, and the heat dissipation cavity is communicated with the liquid flow channel. Therefore, the cooling liquid can be prevented from being in contact with the power module, and compared with the prior art that the power module and the pin fins are sealed in a plastic package mode, the assembly difficulty of the heat dissipation structure can be reduced to a great extent, so that the assembly efficiency of the heat dissipation structure can be improved. In the heat dissipation process, heat generated by the power module can be transmitted to the pin fins, and then water cooling can be directly carried out under the action of the cooling liquid, so that the heat dissipation effect of the power module can be ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor heat dissipation, in particular to a heat dissipation structure. Background Art

[0002] A power module is a packaged unit that integrates one or more power semiconductor devices. It is a key component in power electronic systems and is mainly used for high-efficiency, high-power density power conversion and control. With the rapid development of the semiconductor industry, the requirements for miniaturization, simplification and high frequency of power modules are constantly increasing, resulting in an increase in the heat generated during operation. Therefore, the heat dissipation function of the power module also needs to be continuously improved.

[0003] At present, power modules are mostly cooled by indirect water cooling or direct water cooling. When indirect water cooling is used, a cold plate is often set on the heat dissipation surface of the power module. A water channel for flowing coolant is set inside the cold plate. The coolant can absorb heat during the flow process. Then the coolant that absorbs heat flows to the heat dissipation structure, and under the action of the heat dissipation structure, it can complete heat exchange with the air. Finally, the coolant will flow back to the cold plate again after cooling to form a cycle.

[0004] In addition, due to the presence of tiny bumps on the surface of the power module, there is a gap between the power module and the cold plate, and the gap will be filled with air, which will affect the heat transfer. Therefore, the flatness of the cold plate needs to be ensured during the installation of the cold plate. Because the substrate of the cold plate has a ceramic structure and has high pressure requirements, it is difficult to install the cold plate by welding, that is, it is not convenient to compensate for the above gap by adding solder. Therefore, in the prior art, interface materials are often added between the cold plate and the power module to compensate for the gap. However, on the one hand, due to the different gap sizes, the thickness of the interface materials at various locations varies. The larger the thickness, the worse the heat dissipation efficiency, so it is easy to affect the heat dissipation of the power module. On the other hand, the additional interface material will not only further reduce the assembly efficiency of the power module, but also the interface material will easily dry up and age over time, thereby affecting the service life of the power module.

[0005] When direct water cooling is used, pin fins are often directly set on the power module and placed in the coolant so that heat exchange can be completed directly with the coolant. Compared with the indirect water cooling method, the direct water cooling method can avoid the installation of the cold plate, which can not only simplify the assembly steps of the power module, but also improve the heat dissipation effect. However, in order to avoid contact between the coolant and the power module, the power module and the pin fins are often required to be plastic-sealed, but the current plastic sealing process is relatively complicated, which increases the difficulty of assembling the entire power module. Therefore, compared with the indirect water cooling method, the direct water cooling method used in the prior art does not significantly improve the assembly efficiency of the entire power module.

[0006] Therefore, the above problems need to be solved urgently. Utility Model Content

[0007] The utility model aims to provide a heat dissipation structure to improve the assembly efficiency of a power module and ensure the heat dissipation effect thereof.

[0008] To achieve this purpose, the utility model adopts the following technical solutions:

[0009] A heat dissipation structure, used for dissipating heat from a power module, comprising:

[0010] The pin fin comprises a substrate and a protrusion arranged on the substrate, wherein the substrate is arranged on the heat dissipation surface of the power module;

[0011] The heat dissipation component has a liquid flow channel for conveying cooling liquid and is sealedly connected to the side of the substrate away from the power module to form a heat dissipation cavity for accommodating the protrusion with the substrate, and the heat dissipation cavity is connected to the liquid flow channel.

[0012] The substrate is welded to the heat dissipation surface.

[0013] The heat dissipation component further includes a first shell, a second shell and a locking member. The first shell and the second shell are respectively sealed and connected to the substrate at both sides of the power module. The locking member is used to lock the first shell and the second shell.

[0014] A gap for passing the power terminal and the control terminal of the power module is provided between the first shell and the second shell.

[0015] The locking member is a screw, and the screw is screwed to the first shell and the second shell at the same time.

[0016] The liquid flow channel includes a first flow section and a second flow section, the first flow section is arranged in the first shell, the second flow section is arranged in the second shell, and the first flow section is communicated with the second flow section.

[0017] The liquid flow channel also includes:

[0018] a water inlet pipe, connected to the first flow section, and the water inlet pipe passes through the first shell and is connected to the second flow section;

[0019] A water outlet pipe is communicated with the second flow section, and the water outlet pipe runs through the second shell and is communicated with the first flow section.

[0020] The first shell and the second shell are both provided with a groove facing the heat dissipation surface;

[0021] The heat dissipation structure also includes a sealing ring which is extruded and arranged between the substrate and the groove.

[0022] The groove has a step surface for placing a sealing ring, and the sealing ring can be sleeved on the outer periphery of the substrate.

[0023] The power modules are provided in plurality, and the pin fins and the grooves are provided in plurality, and are all provided in one-to-one correspondence with the power modules.

[0024] Beneficial effects of the utility model:

[0025] In the utility model, the heat dissipation component and the substrate are assembled into a heat dissipation cavity, so that the coolant can be prevented from contacting the power module. Compared with the prior art of sealing the power module and the pin fins by plastic packaging, the assembly difficulty of the heat dissipation structure can be greatly reduced, thereby increasing the assembly efficiency of the heat dissipation structure. During the heat dissipation process, the heat generated by the power module can be transferred to the pin fins, and then directly water-cooled under the action of the coolant, thereby ensuring the heat dissipation effect of the power module. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the heat dissipation structure in an embodiment of the utility model;

[0027] Figure 2 for Figure 1 Explosion diagram of

[0028] Figure 3 It is an exploded diagram of the power module, pin fins and sealing ring in the embodiment of the utility model.

[0029] In the figure:

[0030] 1. Power module;

[0031] 2. Pin fin; 21. Base plate; 22. Protrusion;

[0032] 3. heat dissipation component; 31. groove; 32. first shell; 33. second shell; 34. liquid flow channel; 341. water inlet pipe; 342. water outlet pipe; 35. ear;

[0033] 4. Sealing ring. DETAILED DESCRIPTION

[0034] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0035] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0037] In the description of this embodiment, the terms "upper", "lower", "right", etc., are based on the directions or positions shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0038] At present, the power module is mostly cooled by indirect water cooling and direct water cooling. However, indirect water cooling not only easily leads to low assembly efficiency of the power module, but also the heat dissipation efficiency is mostly not as good as that of direct water cooling. However, when the power module is cooled by direct water cooling, it is necessary to avoid contact between the coolant and the power module. Therefore, the sealing of the power module is mostly ensured by plastic sealing in the prior art. However, the process of plastic sealing is relatively complicated, resulting in low assembly efficiency of the power module. For this reason, a heat dissipation structure for dissipating heat from the power module is proposed in this embodiment, which uses direct water cooling to cool the power module and uses mechanical sealing to avoid contact between the coolant and the main unit.

[0039] Specifically, see Figure 1 and Figure 2 The heat dissipation structure includes a pin fin 2 and a heat dissipation component 3. The pin fin 2 includes a substrate 21 and a protrusion 22 arranged on the substrate 21. The substrate 21 is arranged on the heat dissipation surface of the power module 1; the heat dissipation component 3 has a liquid flow channel 34 for conveying coolant, and is sealed and connected to the side of the substrate 21 away from the power module 1, so as to be assembled with the substrate 21 to form a heat dissipation cavity for accommodating the protrusion 22, and the heat dissipation cavity is connected to the liquid flow channel 34.

[0040] It is understandable that by assembling the heat dissipation component 3 and the substrate 21 to form a heat dissipation cavity, the coolant can be prevented from contacting the power module 1. Compared with the prior art of sealing the power module 1 and the pin fins 2 by plastic packaging, the assembly difficulty of the power module 1 can be greatly reduced, thereby increasing the assembly efficiency of the power module 1. During the heat dissipation process, the heat generated by the power module 1 can be transferred to the pin fins 2, and then directly water-cooled under the action of the coolant, thereby ensuring the heat dissipation effect of the power module 1.

[0041] Since the pin fins 2 have a certain flexibility, in the present embodiment, the substrate 21 is preferably welded to the heat dissipation surface by welding. Moreover, during the welding process, solder can be added between the substrate 21 and the heat dissipation surface to fill the tiny bumps on the surface of the substrate 21. Compared with the method of using interface materials to compensate for the tiny bumps in the prior art, it can not only further improve the assembly efficiency of the power module 1, but also avoid the problems of the interface material drying up and aging over time.

[0042] In addition, under the action of welding pressure, the pin fins 2 having a certain flexibility can make the substrate 21 fit better with the heat dissipation surface, thereby further ensuring the heat dissipation effect of the heat dissipation surface.

[0043] Please combine Figure 2 and Figure 3For reference, in order to improve the heat dissipation efficiency of the heat dissipation structure, it is necessary to perform double-sided heat dissipation on the power module 1. Pin fins 2 are set on both sides of the power module 1, and heat is dissipated by direct water cooling. Specifically, the heat dissipation component 3 also includes a first shell 32, a second shell 33 and a locking piece. The first shell 32 and the second shell 33 are respectively sealed and connected to the substrate 21 on both sides of the power module 1, and the locking piece is used to lock the first shell 32 and the second shell 33. In actual applications, when assembling the heat dissipation structure, pin wings 2 are first provided on both the front and back sides of the power module 1, and then the first shell 32 is placed on the front side of the power module 1, and the first shell 32 and the substrate 21 on the front side can be sealed to form a heat dissipation cavity for front heat dissipation, and the second shell 33 is placed on the back side of the power module 1, and the second shell 33 and the substrate 21 on the back side are assembled to form a heat dissipation cavity for back heat dissipation, and finally the first shell 32 and the second shell 33 are locked by a locking piece, so that the power module 1 can be clamped between the first shell 32 and the second shell 33, and the coolant can be prevented from leaking out of the heat dissipation cavity, thereby increasing the safety performance of the heat dissipation structure. In addition, compared with preventing the coolant from contacting the power module 1 by plastic sealing, the coolant is prevented from contacting the power module 1 by mechanical sealing in this embodiment, and the whole process is relatively convenient and quick, thereby improving the assembly efficiency of the power module 1.

[0044] Furthermore, a gap is provided between the first housing 32 and the second housing 33 for inserting the power terminals and the control terminals of the power module 1. It is understandable that after the first housing 32 and the second housing 33 are installed, there is a gap for inserting the power terminals and the control terminals of the power module 1, so that when assembling the power module 1, there is no need to consider the problem of inserting the power terminals and the control terminals, so the assembly efficiency of the power module 1 can be further improved.

[0045] See also Figure 2 In order to ensure that the coolant in the heat dissipation cavity on both sides can be continuously transported, the liquid flow channel 34 includes a first flow section and a second flow section, the first flow section is arranged in the first shell 32, the second flow section is arranged in the second shell 33, and the first flow section is connected to the second flow section. It can be understood that the coolant in the first flow section and the coolant in the second flow section belong to the same cooling source, and can flow through the first flow section and the second flow section in sequence, and then flow back to the cooling source. Such a setting can reduce the occupied area of ​​the heat dissipation structure, thereby meeting the production requirements of miniaturization and simplification of the heat dissipation structure.

[0046] In addition, the liquid flow channel 34 also includes an inlet pipe 341 and an outlet pipe 342. The inlet pipe 341 is connected to the first flow section, and the inlet pipe 341 passes through the first shell 32 and is connected to the second flow section; the outlet pipe 342 is connected to the second flow section, and the outlet pipe 342 passes through the second shell 33 and is connected to the first flow section. It can be understood that the coolant flows out from the cooling source and is divided into two streams after entering the inlet pipe 341. One stream enters the first flow section through the inlet pipe 341, and then passes through multiple heat dissipation chambers to complete heat exchange. After the heat exchange is completed, it flows out from the outlet pipe 342 and finally enters the next cycle after cooling. The other stream enters the second flow section through the inlet pipe 341, and then passes through multiple heat dissipation chambers to complete heat exchange. After the heat exchange is completed, it flows out from the outlet pipe 342 and finally enters the next cycle after cooling. Such a setting can avoid the influence between the front heat dissipation and the back heat dissipation of the power module 1, thereby improving the heat dissipation efficiency. In addition, the provision of the water inlet pipe 341 and the water outlet pipe 342 can ensure that a gap is reserved between the first shell 32 and the second shell 33 during assembly, thereby facilitating the insertion of power terminals and control terminals of the power module 1 .

[0047] Furthermore, a certain gap is provided between the bottom of the groove 31 and the liquid flow channel 34 to form a branch flow channel, and the groove 31 is provided with water outlets on both side walls along the flow direction of the coolant to ensure the supply and flow of the coolant in the groove 31. It can be understood that when the coolant is about to enter the heat dissipation cavity, the coolant is divided into two streams, one of which enters the branch flow channel and does not participate in the heat exchange, and the other enters the groove 31 and participates in the heat exchange. After the heat exchange is completed, the two streams will be reunited into one stream, so that the coolant participating in the heat exchange can be cooled, thereby reducing or even completely avoiding the impact on the heat exchange in the heat dissipation cavity on the downstream side, thereby improving the heat dissipation effect of the power module 1.

[0048] In this embodiment, the locking member is a screw, and the screw is screwed to the first shell 32 and the second shell 33 at the same time. Specifically, a plurality of ears 35 are provided on the first shell 32 and the second shell 33, and the ears 35 on the first shell 32 are arranged opposite to the ears 35 on the second shell 33. The screw can be screwed to the two ears 35 at the same time to complete the locking of the first shell 32 and the second shell 33.

[0049] Please combine Figure 2 and Figure 3For reference, in order to prevent the coolant in the heat dissipation cavity from leaking out after the power module 1 is assembled, in this embodiment, the first shell 32 and the second shell 33 are both provided with a groove 31 facing the heat dissipation surface; the heat dissipation structure also includes a sealing ring 4, which is extruded and arranged between the substrate 21 and the groove 31. It can be understood that under the action of the locking member, the first shell 32 and the second shell 33 can apply a clamping force to the power module 1. At this time, the power module 1 can apply a reaction force to the first shell 32 and the second shell 33. Under the action of the clamping force and the reaction force, the sealing ring 4 can be squeezed and fixed, thereby improving the sealing performance of the heat dissipation cavity. In addition, during the extrusion process, the sealing ring 4 can be deformed, thereby compensating for the flatness of the power module 1, thereby reducing the flatness and flatness requirements of the power module 1 during the production process, thereby reducing the manufacturing cost of the power module 1.

[0050] Specifically, the groove 31 has a stepped surface for placing the sealing ring 4, and the sealing ring 4 can be sleeved on the outer periphery of the substrate 21. It can be understood that after the sealing ring 4 is arranged on the stepped surface, the inner wall of the groove 31 and the substrate 21 can clamp the sealing ring 4, thereby preventing the sealing ring 4 from shifting, and further ensuring the sealing of the heat dissipation cavity.

[0051] See also Figure 2 When there are multiple power modules 1, there are multiple pin fins 2 and grooves 31, and they are arranged one by one with the power modules 1. It can be understood that the pin fins 2 and grooves 31 constitute a heat dissipation structure, and the heat dissipation structure of each power module 1 is independently arranged. Compared with the prior art of welding the cold plate to multiple power modules 1 at the same time, such an arrangement can reduce the difficulty of installing the substrate 21, thereby improving the welding yield. And the number of heat dissipation structures can be changed according to actual working conditions, thereby improving the applicability of the heat dissipation structure.

[0052] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A heat dissipation structure for dissipating heat from a power module (1), characterized in that: include: The pin fin (2) comprises a substrate (21) and a protrusion (22) arranged on the substrate (21), wherein the substrate (21) is arranged on the heat dissipation surface of the power module (1); The heat dissipation component (3) has a liquid flow channel (34) for conveying cooling liquid, and is sealedly connected to a side of the substrate (21) facing away from the power module (1) so as to be assembled with the substrate (21) to form a heat dissipation cavity for accommodating the protrusion (22), and the heat dissipation cavity is in communication with the liquid flow channel (34).

2. The heat dissipation structure according to claim 1, characterized in that: The substrate (21) is welded to the heat dissipation surface.

3. The heat dissipation structure according to claim 1, characterized in that: The heat dissipation component (3) further comprises a first shell (32), a second shell (33) and a locking member, wherein the first shell (32) and the second shell (33) are respectively sealed and connected to the substrate (21) located at both sides of the power module (1), and the locking member is used to lock the first shell (32) and the second shell (33).

4. The heat dissipation structure according to claim 3, characterized in that: A gap is provided between the first shell (32) and the second shell (33) for passing the power terminal and the control terminal of the power module (1).

5. The heat dissipation structure according to claim 3, characterized in that: The locking member is a screw, and the screw is screwed to the first shell (32) and the second shell (33) at the same time.

6. The heat dissipation structure according to claim 3, characterized in that: The liquid flow channel (34) comprises a first flow section and a second flow section, the first flow section is arranged in the first shell (32), the second flow section is arranged in the second shell (33), and the first flow section is communicated with the second flow section.

7. The heat dissipation structure according to claim 6, characterized in that: The liquid flow channel (34) further comprises: a water inlet pipe (341) connected to the first flow section, and the water inlet pipe (341) passes through the first shell (32) and is connected to the second flow section; A water outlet pipe (342) is communicated with the second flow section, and the water outlet pipe (342) passes through the second shell (33) and is communicated with the first flow section.

8. The heat dissipation structure according to claim 3, characterized in that: The first shell (32) and the second shell (33) are both provided with a groove (31) facing the heat dissipation surface; The heat dissipation structure also includes a sealing ring (4) which is extruded and arranged between the substrate (21) and the groove (31).

9. The heat dissipation structure according to claim 8, characterized in that: The groove (31) has a stepped surface for placing a sealing ring (4), and the sealing ring (4) can be sleeved on the outer periphery of the base plate (21).

10. The heat dissipation structure according to claim 8, characterized in that: The power module (1) is provided in plurality, and the pin fins (2) and the grooves (31) are both provided in plurality, and are all provided in a one-to-one correspondence with the power module (1).

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