Novel power device two-phase heat dissipation module structure

Abstract

The utility model relates to a novel power device two-phase heat dissipation module structure. The novel power device two-phase heat dissipation module structure comprises a cooling water upper cover plate, cooling water channel fins, a cooling water loop and refrigerant loop heat exchange plate, a refrigerant vapor state bin, a refrigerant flowing loop, a refrigerant liquid state bin and a refrigerant loop lower cooling plate which are connected in sequence. The cooling water upper cover plate is provided with a cooling liquid inlet and a cooling liquid outlet, the refrigerant vapor state bin is provided with a refrigerant injection port, and the refrigerant loop lower cooling plate is fixedly connected with a power device needing heat dissipation. Compared with the prior art, the utility model has the advantages of higher heat exchange efficiency, good temperature equalization and heat dissipation performance and suitability for high-power density equipment: a refrigerant is used as a medium, has higher specific heat capacity and heat transfer coefficient, is beneficial to phase change potential to absorb and transfer heat more quickly, and can reduce the temperature of a power device more effectively; refrigerant cooling is suitable for high-power-density equipment, and the two-phase cooling temperature uniformity is good; the power device is connected with the cold plate in a welding mode, thermal resistance is reduced, and heat exchange is better achieved.

Description

Technical Field

[0001] The utility model relates to a power device heat dissipation structure, in particular to a novel two-phase heat dissipation module structure of a power device. Background Art

[0002] Power devices mainly refer to electronic components designed to handle high voltage and high current to achieve power conversion and control, such as MOSFET, IGBT, power diode, etc. They are widely used in power management, motor drive, new energy vehicles, inverters and various industrial control equipment, and are the key to efficient energy utilization.

[0003] At present, the main cooling methods for power devices in the industry are air cooling and liquid cooling. The power device is directly installed on the radiator, and the heat of the power device is directly transferred to the radiator shell through the TIM, and then the heat is taken away by air cooling or liquid cooling forced convection.

[0004] Air cooling of power devices uses air convection to transfer heat to achieve the purpose of heat dissipation. It is characterized by high heat dissipation efficiency, low cost, high reliability, simple structure and easy maintenance. However, traditional air cooling has always been restricted by the level of radiator technology, molds, processing capabilities, small specific heat capacity of air, low thermal conductivity, etc. Even with forced convection air cooling, the heat dissipation capacity is very limited and cannot well cope with the heat dissipation needs of power device integrated modules with high heat flux density and fast instantaneous temperature rise. In addition, there are problems such as temperature unevenness and noise.

[0005] Liquid cooling of power devices has high heat dissipation efficiency, small size, and easier layout of the heat dissipation system. However, there is a problem of low temperature uniformity. The cooling performance is good near the inlet, while the cooling performance is greatly reduced near the outlet, and the temperature non-uniformity will be more prominent. For power devices, power will increase as the junction temperature of the power device chip decreases. Poor temperature uniformity will cause different junction temperatures between power device chips at different positions, making each power device chip have different power conversion efficiency, affecting the operation of the module, and in severe cases, even causing thermal runaway and damage during operation.

[0006] Patent CN202222548444.1 discloses a high-performance separated vapor-liquid two-phase heat exchange radiator, including a separated functional module area and a heat exchange area, the functional module area includes a high-power semiconductor device and an enhanced heat exchange substrate, the heat exchange area includes a vapor-liquid two-phase radiator and a fan assembly, the upper and lower ends of the vapor-liquid two-phase radiator are respectively connected with a steam chamber and a condensation chamber, the two are respectively connected with the enhanced heat exchange substrate to form a closed cavity, and a phase change working medium is injected into the closed cavity, the enhanced heat exchange substrate includes a cavity structure surrounded by a cover plate, a shell and a shell side wall, an inner concave cavity capillary structure is arranged on the inner surface of the cavity structure, and a reinforcement structure is also provided on the inner surface of the cavity structure, and a welding structure step of equal height is reinforced on the inner side of the shell side wall to form a welding surface, and the cover plate is welded on the welding surface to form a complete enhanced heat exchange substrate. However, the patent adopts the air cooling principle for heat dissipation, and its heat dissipation efficiency is lower than the heat dissipation method through the coolant circuit, and the structure is complex and occupies a large space. Utility Model Content

[0007] The purpose of the utility model is to provide a new type of two-phase heat dissipation module structure for power devices in order to overcome the defects of uneven heat dissipation and low heat dissipation efficiency in the above-mentioned prior art.

[0008] The purpose of the utility model can be achieved through the following technical solutions:

[0009] During the process of conception, the applicant believes that the phase change heat dissipation of power devices utilizes the principle of heat absorption during phase change of materials to convert the heat emitted by the heat source into latent heat of phase change. It has the following advantages: higher heat transfer efficiency: phase change materials have higher thermal conductivity and can transfer and disperse heat more effectively; wider temperature adaptability range: phase change materials have a wide phase change temperature range and can be used in a wider temperature range; better heat absorption performance: phase change materials can absorb a large amount of heat during the phase change process, thereby reducing the temperature of the equipment; better chemical stability: phase change materials have better chemical stability and can maintain the stability of their performance under various environmental conditions.

[0010] The utility model provides a novel two-phase heat dissipation module structure of a power device, including a cooling water channel cover plate, cooling water channel fins, cooling water circuit and refrigerant circuit heat exchange plate, refrigerant vapor state bin, refrigerant flow circuit, refrigerant liquid bin, and refrigerant circuit lower cold plate connected in sequence;

[0011] A coolant inlet and a coolant outlet are arranged on the cover plate of the cooling water circuit, a coolant injection port is arranged on the coolant vapor state bin, and the cold plate under the coolant circuit is fixedly connected to the power device that needs heat dissipation.

[0012] Furthermore, the coolant inlet and the coolant outlet are respectively connected to the cooling water channel cover plate by brazing.

[0013] Furthermore, the cooling water channel cover plate, the cooling water channel fins, the cooling water circuit and the refrigerant circuit heat exchange plate are all brazed and connected.

[0014] Furthermore, the cooling water channel fins are plate fin array fins or staggered plate fin array fins.

[0015] Furthermore, the refrigerant vapor tank, the refrigerant flow circuit, the refrigerant liquid tank, and the refrigerant injection port are integrated into a structure.

[0016] Furthermore, the refrigerant flow circuit includes a first tube group and a second tube group, the first tube group is used to deliver the vapor refrigerant from the refrigerant liquid tank into the refrigerant vapor tank, and the second tube group is used to deliver the liquid refrigerant from the refrigerant vapor tank into the refrigerant liquid tank.

[0017] Furthermore, the cold plate under the refrigerant circuit and the power devices that need to dissipate heat are fixed by high-temperature welding.

[0018] Furthermore, the refrigerant liquid tank and the lower cold plate of the refrigerant circuit are connected by brazing.

[0019] Furthermore, the cooling water circuit, the refrigerant circuit heat exchange plates and the refrigerant vapor bin are brazed and connected.

[0020] Furthermore, the cover plate on the cooling water circuit, the heat exchange plate of the cooling water circuit and the refrigerant circuit, and the lower cold plate of the refrigerant circuit are all made of aluminum plates.

[0021] The utility model has higher heat exchange efficiency, good uniform temperature heat dissipation, and is suitable for high power density equipment: the refrigerant as a medium has a higher specific heat capacity and heat transfer coefficient, which is beneficial to the phase change potential and can absorb and transfer heat faster. Compared with the coolant, the refrigerant can more effectively reduce the temperature of the power device; refrigerant cooling is suitable for high power density equipment, and the two-phase cooling has good temperature uniformity, which can effectively absorb and disperse a large amount of heat to ensure the stable operation of the equipment; the refrigerant heat dissipation is through the coolant circuit, which is more efficient than air cooling; the power device is connected to the cold plate by welding to reduce thermal resistance and better achieve heat exchange.

[0022] Working principle:

[0023] The reasons why power devices generate heat: When the power device is turned on, there will be resistance between the collector and the emitter, and the current will generate heat when passing through the resistance; during the switching process of the power device, switching losses will be generated due to current changes and voltage switching, and these losses will convert energy into heat; there is a certain resistance in the drift interval (N zone) inside the power device, and heat will be generated when current passes through.

[0024] When the power device that needs to dissipate heat generates heat, the welded cold plate under the refrigerant circuit can exchange heat with the liquid refrigerant in the refrigerant liquid tank. After absorbing heat, the liquid refrigerant evaporates and turns into a vapor state, and a large amount of steam is generated at the same time. The steam then passes through the refrigerant flow circuit and enters the refrigerant vapor tank. After that, the refrigerant in the refrigerant vapor tank exchanges heat with the cooling water circuit fins through the cooling water circuit and the refrigerant circuit heat exchange plate, realizing condensation and heat release, and then turns back into liquid state and flows back to the liquid tank through the exchange channel to continue circulation. The design of the coolant circuit with fins is mainly used to increase the contact surface with the coolant, while preventing the formation of fluid laminar flow and reducing thermal resistance.

[0025] Compared with the prior art, the utility model has the following advantages:

[0026] (1) Higher heat transfer efficiency, good uniform temperature heat dissipation, suitable for high power density equipment: As a medium, the refrigerant has a higher specific heat capacity and heat transfer coefficient, which is conducive to the phase change potential to absorb and transfer heat faster. Compared with the coolant, the refrigerant can more effectively reduce the temperature of the power device; refrigerant cooling is suitable for high power density equipment, and the two-phase cooling has good temperature uniformity, which can effectively absorb and disperse a large amount of heat to ensure the stable operation of the equipment; the refrigerant heats away the heat through the coolant circuit, which is more efficient than air cooling; the power device is connected to the cold plate by welding to reduce thermal resistance and better achieve heat exchange.

[0027] (2) The structure is compact and occupies little space: the vapor refrigerant is mainly heat-exchanged with the coolant through the cooling water circuit and the refrigerant circuit heat exchange plate. The vapor-liquid flow pipeline formed by the refrigerant vapor tank, the refrigerant flow circuit, and the refrigerant liquid tank is only considered for the vapor-liquid exchange of the refrigerant, and can be well installed on a compact work platform.

[0028] (3) It is maintainable, durable, stable, and low-cost. The current device can be made entirely of aluminum. Short pipelines can reduce the risk of external impact. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is an exploded view of the two-phase heat dissipation module structure of a new power device;

[0030] Figure 2 This is a front view of the two-phase heat dissipation module structure of a new power device;

[0031] Figure 3 It is a three-dimensional schematic diagram of the structure of a two-phase heat dissipation module of a new power device;

[0032] Figure 4 Schematic diagram of heat flux of phase change material;

[0033] Figure 5Schematic diagram of test results for the same power device using two-phase cooling and traditional liquid cooling.

[0034] Figure markings: 1-cooling liquid inlet, 2-cooling liquid outlet, 3-cooling water channel cover, 4-cooling water channel fins, 5-cooling water circuit and refrigerant circuit heat exchange plate, 6-refrigerant vapor bin, 7-refrigerant flow circuit, 8-refrigerant liquid injection port, 9-refrigerant liquid bin, 10-refrigerant circuit lower cold plate, 11-power devices that need heat dissipation. DETAILED DESCRIPTION

[0035] The following is a detailed description of the present invention in conjunction with the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms and other features not clearly described in this technical solution are all considered to be common technical features disclosed in the prior art.

[0036] Example 1

[0037] In the current solution, the power device 11 that needs heat dissipation is an IGBT half-bridge. Table 1 shows the performance indicators of the refrigerant. The power device 11 that needs heat dissipation is welded to the bottom surface of the cold plate 10 under the refrigerant circuit. Through the new heat dissipation structure, heat is exchanged with the low-boiling-point refrigerant. The liquid refrigerant in the refrigerant liquid tank 9 absorbs the heat of the power device and then boils and vaporizes. The high-temperature vapor refrigerant produced by vaporization has a small density and will gradually converge to the refrigerant vapor tank 6 through the upper channel and then pass through the cooling water circuit and the refrigerant circuit heat exchange plate 5 to exchange heat with the coolant and condense into a low-temperature liquid refrigerant. Under the action of gravity, it returns to the refrigerant liquid tank 9, thereby achieving a good heat dissipation effect, allowing the power device to be used in a more efficient scenario.

[0038] This device can be applied to industrial and automotive-grade module heat dissipation structures. For automotive inverters, this structure needs to be placed sideways to ensure that the refrigerant can still completely cover the cold plate when the vehicle goes up and down the slope to ensure good heat absorption.

[0039] Table 1

[0040]

[0041] Under the same conditions, the amount of heat absorbed by refrigerants and coolants depends on their physical properties, and heat flux can well reflect this characteristic. Refrigerants usually have a higher latent heat of vaporization, which allows them to absorb a large amount of heat during the phase change process, and have better thermal uniformity than coolants. Figure 4 As shown, the test shows that the heat flux of phase change material is the largest.

[0042] like Figure 5The figure shows the test results of the same power device using two-phase cooling and traditional liquid cooling, respectively. It shows that under peak conditions, with the same mass flow rate, the maximum temperature of the power device using the two-phase cooling structure is 11°C lower than the traditional liquid cooling temperature when comparing the refrigerant (Ref) with the coolant (EG 50 / 50).

[0043] This embodiment provides a novel two-phase heat dissipation module structure for power devices, such as Figure 1 , Figure 2 , Figure 3 As shown, it includes a cooling water channel cover plate 3, a cooling water channel fin 4, a cooling water circuit and a refrigerant circuit heat exchange plate 5, a refrigerant vapor state bin 6, a refrigerant flow circuit 7, a refrigerant liquid bin 9, and a refrigerant circuit lower cold plate 10 connected in sequence;

[0044] A coolant inlet 1 and a coolant outlet 2 are provided on the cooling water channel cover plate 3, a coolant injection port 8 is provided on the coolant vapor chamber 6, and a coolant circuit lower cold plate 10 is fixedly connected to a power device 11 that needs heat dissipation.

[0045] In a specific embodiment, the coolant inlet 1 and the coolant outlet 2 are respectively connected to the cooling water channel cover plate 3 by brazing.

[0046] In a specific embodiment, the cooling water channel cover plate 3, the cooling water channel fins 4, the cooling water circuit and the refrigerant circuit heat exchange plate 5 are all brazed and connected.

[0047] In a specific embodiment, the cooling water channel fins 4 are plate fin array fins.

[0048] In a specific embodiment, the refrigerant vapor tank 6, the refrigerant flow circuit 7, the refrigerant liquid tank 9, and the refrigerant injection port 8 are an integrated structure.

[0049] In a specific embodiment, the refrigerant flow circuit 7 includes a first tube group and a second tube group, the first tube group is used to deliver the vapor refrigerant from the refrigerant liquid tank 9 into the refrigerant vapor tank 6, and the second tube group is used to deliver the liquid refrigerant from the refrigerant vapor tank 6 into the refrigerant liquid tank 9.

[0050] In a specific implementation, the cold plate 10 under the refrigerant circuit and the power device 11 that needs to dissipate heat are fixed by high-temperature welding.

[0051] In a specific implementation, the refrigerant liquid tank 9 and the refrigerant circuit lower cold plate 10 are connected by brazing.

[0052] In a specific embodiment, the cooling water circuit and the refrigerant circuit heat exchange plate 5 and the refrigerant vapor tank 6 are connected by brazing.

[0053] In a specific embodiment, the cooling water circuit cover plate 3, the cooling water circuit and refrigerant circuit heat exchange plate 5, and the refrigerant circuit lower cold plate 10 are all aluminum plates.

[0054] Working principle:

[0055] The reasons why power devices generate heat: When the power device is turned on, there will be resistance between the collector and the emitter, and the current will generate heat when passing through the resistance; during the switching process of the power device, switching losses will be generated due to current changes and voltage switching, and these losses will convert energy into heat; there is a certain resistance in the drift interval (N zone) inside the power device, and heat will be generated when current passes through.

[0056] When the power device 11 that needs to dissipate heat generates heat, the welded cold plate 10 under the refrigerant circuit can exchange heat with the liquid refrigerant in the refrigerant liquid tank 9. The liquid refrigerant evaporates and becomes vapor after absorbing heat, and a large amount of steam is generated at the same time. The steam then passes through the refrigerant flow circuit 7 and enters the refrigerant vapor tank 6. After that, the refrigerant in the refrigerant vapor tank 6 exchanges heat with the cooling water circuit fins 4 through the cooling water circuit and the refrigerant circuit heat exchange plate 5, realizing condensation and heat release, and then turns into liquid again and flows back to the liquid tank 9 through the exchange channel to continue circulation. The design of the coolant circuit with fins is mainly used to increase the contact surface with the coolant, while preventing the formation of fluid laminar flow and reducing thermal resistance.

[0057] Components not described in detail in this embodiment are all existing components that can be purchased through public channels.

[0058] The above description of the embodiments is to facilitate the understanding and use of the utility model by those skilled in the art. It is obvious that those familiar with the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the utility model is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the utility model without departing from the scope of the utility model should be within the scope of protection of the utility model.

Claims

1. A novel two-phase heat dissipation module structure for power devices, characterized in that: It comprises a cooling water channel upper cover plate (3), cooling water channel fins (4), a cooling water circuit and a refrigerant circuit heat exchange plate (5), a refrigerant vapor state bin (6), a refrigerant flow circuit (7), a refrigerant liquid state bin (9), and a refrigerant circuit lower cold plate (10) which are connected in sequence; The cooling water circuit cover plate (3) is provided with a coolant inlet (1) and a coolant outlet (2), the refrigerant vapor chamber (6) is provided with a refrigerant injection port (8), and the refrigerant circuit lower cold plate (10) is fixedly connected to a power device (11) that needs to dissipate heat.

2. A novel two-phase heat dissipation module structure for power devices according to claim 1, characterized in that: The cooling liquid water inlet (1) and the cooling liquid water outlet (2) are respectively connected to the cooling water channel cover plate (3) by brazing.

3. According to claim 1, a novel two-phase heat dissipation module structure for power devices is characterized in that: The cooling water channel cover plate (3), the cooling water channel fins (4), the cooling water circuit and the refrigerant circuit heat exchange plate (5) are all brazed and connected.

4. The novel two-phase heat dissipation module structure of power device according to claim 1 is characterized in that: The cooling water channel fins (4) are plate fin array fins or staggered plate fin array fins.

5. The novel two-phase heat dissipation module structure of power device according to claim 1 is characterized in that: The refrigerant vapor tank (6), the refrigerant flow circuit (7), the refrigerant liquid tank (9), and the refrigerant liquid injection port (8) are an integrated structure.

6. A novel two-phase heat dissipation module structure for power devices according to claim 1, characterized in that: The refrigerant flow circuit (7) comprises a first tube group and a second tube group, wherein the first tube group is used to deliver the vapor refrigerant from the refrigerant liquid tank (9) into the refrigerant vapor tank (6), and the second tube group is used to deliver the liquid refrigerant from the refrigerant vapor tank (6) into the refrigerant liquid tank (9).

7. The novel two-phase heat dissipation module structure of power device according to claim 1 is characterized in that: The lower cold plate (10) of the refrigerant circuit and the power device (11) requiring heat dissipation are fixed by high-temperature welding.

8. The novel two-phase heat dissipation module structure of power device according to claim 1 is characterized in that: The refrigerant liquid tank (9) and the lower cold plate (10) of the refrigerant circuit are connected by brazing.

9. The novel two-phase heat dissipation module structure of power device according to claim 1 is characterized in that: The cooling water circuit and the refrigerant circuit heat exchange plate (5) are connected with the refrigerant vapor state bin (6) by brazing.

10. A novel two-phase heat dissipation module structure for power devices according to claim 1, characterized in that: The cooling water circuit upper cover plate (3), the cooling water circuit and refrigerant circuit heat exchange plate (5), and the refrigerant circuit lower cold plate (10) are all aluminum plates.

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