Two-phase radiator and power conversion device

Abstract

The invention provides a two-phase radiator and a power conversion device, and relates to the field of photovoltaic technology. The power conversion device comprises a power shell, a heating device and a two-phase radiator. The power shell is provided with a mounting cavity for accommodating the heating device and an opening communicated with the mounting cavity. The two-phase radiator comprises an evaporator and a condenser which are communicated. The evaporator covers the opening and comprises a base plate and a cover plate, the base plate is located between the cover plate and the heating device and connected with the heating device, and the base plate is connected with the cover plate and defines an evaporation cavity with the cover plate; and a two-phase cooling working medium which is used for absorbing heat generated by the heating device and generating phase change circulation between the evaporator and the condenser is arranged in the evaporation cavity. The substrate comprises a first part and a second part, the first part and the second part are adjacently connected in the direction perpendicular to the thickness direction of the substrate, the heating device is connected with the first part, the first part is made of copper, and the second part is made of aluminum. The heat resistance can be reduced, and the heat exchange boiling capacity of the working medium is enhanced.

Description

Technical Field

[0001] This application relates to the field of photovoltaic technology, and in particular to a two-phase heat sink and power conversion device. Background Technology

[0002] With the continuous increase in the power density of photovoltaic inverters, heat dissipation has become a key challenge restricting the lifespan and stability of the equipment. Traditional air-cooling solutions rely on a combination of fans and heat sinks, which are difficult to meet the demands of higher power density in terms of size and cost. Two-phase siphon cooling technology, due to its efficient heat transfer capabilities, has become a potential solution for achieving low-cost, high-performance heat dissipation.

[0003] Current two-phase siphon heat sinks are mostly made of aluminum. However, while aluminum has the advantages of low cost and corrosion resistance, its inherent thermal conductivity is limited, resulting in a relatively high overall thermal resistance of the heat sink, making it difficult to meet the ever-increasing demand for high heat flux density. To compensate for its performance shortcomings, the size of the heat sink often needs to be increased, which in turn increases the structural volume and manufacturing cost. In addition, the boiling heat transfer capacity of the aluminum substrate surface is relatively low, which can easily cause localized drying of the working fluid under high heat flux density conditions, leading to interruption of phase change cycle and failure of heat dissipation function, thus limiting its reliability and performance limits in high-power scenarios. Summary of the Invention

[0004] This application provides a two-phase heat sink and a power conversion device. The two-phase heat sink and power conversion device can reduce thermal resistance, enhance the heat exchange boiling capacity of the working fluid, and improve the heat dissipation performance of the two-phase heat sink in high heat flux density scenarios.

[0005] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0006] On one hand, this application provides a power conversion device, which includes a power housing, a heating element, and a two-phase heat sink. The power housing has a mounting cavity and an opening communicating with the mounting cavity, the mounting cavity being used to house the heating element. The two-phase heat sink includes an evaporator and a condenser, the evaporator and condenser being in communication. The evaporator closes the opening and is fixedly connected to the power housing. The evaporator includes a substrate and a cover plate, the substrate being located between the cover plate and the heating element and connected to the heating element. The substrate connects to the cover plate and encloses the cover plate to form an evaporation cavity. A two-phase cooling medium is disposed within the evaporation cavity, the two-phase cooling medium being used to absorb heat generated by the heating element and undergo a phase change cycle between the evaporator and the condenser. The substrate includes a first part and a second part, the first part and the second part being adjacent along a direction perpendicular to the thickness of the substrate. The heating element is connected to the first part, the first part is made of copper, and the second part is made of aluminum.

[0007] In the power conversion device provided in this application, the first part of the substrate connected to the heating device is made of copper, which has a high thermal conductivity, while the second part of the substrate not connected to the heating device is made of aluminum. In this way, the copper first part can quickly introduce and spread the heat transferred by the heating device laterally, reducing the thermal resistance of conduction and diffusion from the heating device to the two-phase cooling medium in the evaporation chamber. This allows the heat to be quickly transferred to the two-phase cooling medium. The rapid introduction of heat causes the two-phase cooling medium to activate nucleation boiling earlier and more violently, resulting in more frequent bubble generation and faster detachment per unit area. This avoids local overheating caused by heat accumulation under the heating device, reduces the risk of the two-phase cooling medium burning out in high heat flux density scenarios, and improves the heat dissipation limit and reliability of the two-phase heat sink in high heat flux density scenarios. In addition, the first part connected to the heat-generating device is made of copper, while the second part is made of aluminum. Copper, which is more expensive, is used in local areas with high heat flow, while aluminum, which is lighter and cheaper, is used in areas with low heat load. This avoids the expensive material costs associated with using an all-copper substrate and also reduces the overall weight. As a result, this application optimizes the manufacturing cost of the heat sink while ensuring heat dissipation performance, achieving a better balance between heat dissipation performance and cost.

[0008] In one implementation, the first part has a plurality of spaced protrusions on the side facing the cover plate, and the plurality of protrusions are located inside the evaporation chamber.

[0009] This application, by incorporating multiple protruding structures, increases the effective contact heat exchange area between the substrate and the two-phase cooling medium within the evaporation chamber. This allows heat to be absorbed and carried away by the medium more efficiently and evenly, enhancing the heat dissipation capacity and the upper limit of the heat flux density that the two-phase radiator can withstand. Furthermore, the multiple protruding structures also provide mechanical support between the cover plate and the substrate. These structures separate and reinforce the evaporation chamber, resisting deformation or vibration of the evaporator caused by phase changes and pressure fluctuations in the two-phase cooling medium. This strengthens the overall structural strength and long-term reliability of the evaporator, ensuring structural integrity and performance stability of the two-phase radiator under high load and high pressure differential conditions.

[0010] In one implementation, the outer wall surface of the protruding structure has an uneven texture.

[0011] This application creates an uneven, textured structure on the outer wall of the raised structure. This structure increases the actual contact area with the two-phase cooling medium, providing a large number of stable vaporization nuclei. This promotes the rapid generation, growth, and detachment of bubbles in the two-phase cooling medium when heated, enhancing the boiling heat transfer intensity of the two-phase cooling medium in the evaporation chamber. As a result, the evaporator can more efficiently stimulate the phase change heat transfer of the two-phase cooling medium when dealing with transient peak power, improving the heat dissipation limit and reliability of the two-phase radiator in high heat flux density scenarios.

[0012] In one implementation, the side of the first part facing the cover plate has an uneven texture.

[0013] Through the above-mentioned configuration, the uneven textured structure in the first part of this application can enhance nucleation boiling, enabling the evaporator to more efficiently excite the phase change heat of the working fluid, thereby improving the heat dissipation performance of the two-phase radiator in high heat flux density scenarios.

[0014] In one implementation, the first part includes a first mounting plate and a second mounting plate. The first mounting plate is located on the side of the second mounting plate opposite to the cover plate and is connected to the heating element. The second mounting plate connects to the first mounting plate and encloses it to form a receiving cavity, which contains a liquid working fluid. The side of the first mounting plate facing the second mounting plate has a first capillary liquid absorption structure, and the side of the second mounting plate facing the first mounting plate has a second capillary liquid absorption structure. The first and second capillary liquid absorption structures are used to transfer heat from the heating element from the first mounting plate to the two-phase cooling working fluid through the phase change cycle of the liquid working fluid.

[0015] The structure described in the first part of this application can achieve an effect comparable to a VC heatsink. Thus, relying on its internal two-phase circulation mechanism, the first part can provide a lateral equivalent thermal conductivity far exceeding that of solid metal, reducing the diffusion thermal resistance from the heating element to the entire evaporator. This allows the heat generated by the heating element to be instantaneously and more evenly diffused throughout the evaporation chamber, improving thermal uniformity and reducing heat flux density. This temperature uniformity reduces localized hot spots generated by the heating element, enabling the two-phase cooling medium within the evaporation chamber to undergo a more intense and uniform boiling phase transition over a wider range. This, in turn, enhances the overall heat dissipation capacity of the two-phase heatsink and its reliability in responding to transient power surges.

[0016] In one implementation, the substrate has an opening extending through the thickness of the substrate; a first portion is disposed within the opening, and the outer wall of the first portion is welded to the inner wall of the opening; a portion of the substrate without an opening is designated as a second portion.

[0017] This application fixes the first and second parts by welding, which is a reliable structure and avoids the introduction of external connection structures, thus simplifying the connection method.

[0018] In one implementation, the substrate has a stepped hole extending through the thickness direction of the substrate; a first portion is disposed within the stepped hole, and a portion of the substrate without a stepped hole is designated as a second portion. The stepped hole includes a first sub-hole and a second sub-hole communicating in the thickness direction of the substrate. The first sub-hole is located on the side of the second sub-hole facing away from the evaporation chamber, and the radial dimension of the first sub-hole is larger than that of the second sub-hole. A portion of the first portion is located within the first sub-hole and contacts the stepped surface of the stepped hole, while another portion of the first portion is located within the second sub-hole.

[0019] This application provides a stepped hole with a first sub-hole and a second sub-hole, and places a portion of the first part in the first sub-hole and another portion of the first part in the second sub-hole. In this way, when assembling the second part and the first part, the first sub-hole and the second sub-hole with different radial dimensions can cooperate with the first part to achieve assembly limit of the first part, which facilitates the positioning of the first part and the second part.

[0020] In one implementation, the portion of the first part located inside the first sub-hole is fixed to the second part by screws, and the portion of the first part located inside the second sub-hole is sealed to the inner wall of the second sub-hole by a sealing ring; or, the portion of the first part located inside the first sub-hole is welded to the inner wall of the first sub-hole, and the portion of the first part located inside the second sub-hole is welded to the inner wall of the second sub-hole.

[0021] This application provides two methods for fixing the first and second parts. One method involves welding, which provides a reliable structure and simplifies the connection. The other method uses screws to fix the first and second parts, facilitating their disassembly and installation. If either part is damaged and needs replacement, the corresponding component can be replaced by removing the screws. The use of a sealing ring improves the sealing performance of the evaporation chamber, preventing leakage.

[0022] In one implementation, the sides of the first and second parts facing away from the cover plate are flush.

[0023] Through the above-mentioned design, this application can avoid the protruding part of the substrate from scratching the devices in the mounting cavity of the power case. Furthermore, the flush first and second parts can make the outer surface of the two-phase heat sink more regular, which can simplify the installation process, facilitate mechanical fixation (such as clamping), and apply uniform pressure, thereby ensuring the stability and reliability of the thermal interface during long-term operation.

[0024] In one implementation, the side of the first part facing the heating element is soldered to the heating element.

[0025] This application welds the heating element to the first part, so that the heat generated by the heating element can be directly transferred to the first part of the evaporator, reducing the thermal resistance in the heat transfer path and improving the heat transfer efficiency.

[0026] In one implementation, the two-phase heat sink further includes a thermally conductive layer, wherein the thermally conductive layer is disposed on the side of the first part facing the heat-generating device, and the first part is connected to the heat-generating device through the thermally conductive layer.

[0027] This application utilizes a thermally conductive layer to fill the microscopic air gaps between the heating element and the first part caused by surface unevenness, eliminating the insulation effect caused by the air layer, reducing interfacial contact thermal resistance, and thus establishing an efficient heat conduction path. Furthermore, the thermally conductive layer also acts as a buffer against mechanical stress, reducing potential mechanical damage to the heating element caused by differences in thermal expansion coefficients and clamping pressure.

[0028] On the other hand, this application provides a two-phase heat sink, which includes an evaporator and a condenser. The evaporator and condenser are connected. The evaporator includes a substrate and a cover plate. The side of the substrate facing away from the cover plate is used to connect to a heat-generating device. The substrate connects to the cover plate and encloses the cover plate to form an evaporation chamber. A two-phase cooling medium is disposed within the evaporation chamber. The two-phase cooling medium absorbs heat generated by the heat-generating device and undergoes a phase change cycle between the evaporator and the condenser. The substrate includes a first portion and a second portion, which are adjacent to each other along a direction perpendicular to the thickness of the substrate. The first portion is used to connect to the heat-generating device, and the first portion is made of copper, while the second portion is made of aluminum.

[0029] In the two-phase heat sink provided in this application, by setting the material of the first part of the substrate connected to the heat-generating device to copper, which has a high thermal conductivity, and setting the material of the second part of the substrate not connected to the heat-generating device to aluminum, the thermal resistance can be reduced, the heat exchange boiling capacity of the working fluid can be enhanced, and the heat dissipation performance of the two-phase heat sink in high heat flux density scenarios can be improved.

[0030] In one implementation, the first part has a plurality of spaced protrusions on the side facing the cover plate, and the plurality of protrusions are located inside the evaporation chamber.

[0031] This application, by setting multiple protruding structures, can increase the effective contact heat exchange area between the substrate and the two-phase cooling medium in the evaporation chamber, thereby improving the heat dissipation capacity and the upper limit of the heat flux density that the two-phase radiator can withstand. In addition, the multiple protruding structures can also provide mechanical support between the cover plate and the substrate, resisting the deformation or vibration of the evaporator caused by the phase change of the two-phase cooling medium and pressure fluctuations.

[0032] In one implementation, the outer wall surface of the protruding structure has an uneven texture.

[0033] By adopting the above-mentioned configuration, this application can increase the actual contact area between the raised structure and the two-phase cooling medium, provide a large number of stable vaporization cores, enhance the boiling heat transfer intensity of the two-phase cooling medium in the evaporation chamber, and improve the heat dissipation limit and reliability of the two-phase radiator in high heat flux density scenarios.

[0034] In one implementation, the side of the first part facing the cover plate has an uneven texture.

[0035] Through the above-mentioned configuration, the uneven textured structure in the first part of this application can enhance nucleation boiling, enabling the evaporator to more efficiently stimulate phase change heat transfer, thereby improving the heat dissipation performance of the two-phase radiator in high heat flux density scenarios.

[0036] In one implementation, the first part includes a first mounting plate and a second mounting plate. The first mounting plate is located on the side of the second mounting plate opposite to the cover plate and is used to connect to the heating device. The second mounting plate connects to the first mounting plate and encloses it to form a receiving cavity, which contains a liquid working fluid. The side of the first mounting plate facing the second mounting plate has a first capillary liquid absorption structure, and the side of the second mounting plate facing the first mounting plate has a second capillary liquid absorption structure. The first and second capillary liquid absorption structures are used to transfer heat from the heating device from the first mounting plate to the two-phase cooling working fluid through a phase change cycle occurring between the two liquid working fluids.

[0037] The structure described in the first part of this application can achieve an effect comparable to that of a VC radiator. In this way, the first part, relying on its internal two-phase circulation mechanism, can provide a lateral equivalent thermal conductivity far exceeding that of solid metal, improve the uniformity of heat conduction, reduce the heat flux density, and enable the two-phase cooling medium in the evaporation chamber to undergo a more intense and uniform boiling phase change over a wider range, thereby improving the overall heat dissipation capacity of the two-phase radiator and its reliability in dealing with transient power surges.

[0038] In one implementation, the substrate has an opening extending through the thickness of the substrate; a first portion is disposed within the opening, and the outer wall of the first portion is welded to the inner wall of the opening. The portion of the substrate without an opening is designated as a second portion.

[0039] This application fixes the first and second parts by welding, which is structurally reliable and avoids the introduction of external connection structures, thus simplifying the connection method.

[0040] In one implementation, the substrate has a stepped hole extending through the thickness direction of the substrate; a first portion is disposed within the stepped hole, and a portion of the substrate without a stepped hole is designated as a second portion. The stepped hole includes a first sub-hole and a second sub-hole communicating in the thickness direction of the substrate. The first sub-hole is located on the side of the second sub-hole facing away from the evaporation chamber, and the radial dimension of the first sub-hole is larger than the radial dimension of the second sub-hole; a portion of the first portion is located within the first sub-hole and contacts the stepped surface of the stepped hole, while another portion of the first portion is located within the second sub-hole.

[0041] With the above-described configuration, when assembling the second part and the first part, the first and second sub-holes with different radial dimensions can cooperate with the first part to achieve assembly limit of the first part, which facilitates the positioning of the first part and the second part.

[0042] In one implementation, the portion of the first part located inside the first sub-hole is fixed to the second part by screws, and the portion of the first part located inside the second sub-hole is sealed to the inner wall of the second sub-hole by a sealing ring; or, the portion of the first part located inside the first sub-hole is welded to the inner wall of the first sub-hole, and the portion of the first part located inside the second sub-hole is welded to the inner wall of the second sub-hole.

[0043] This application provides two methods for fixing the first and second parts. Welding is a simple and reliable method for fixing both parts. Using screws facilitates disassembly and installation. The sealing ring improves the sealing performance of the evaporation chamber, preventing leakage.

[0044] In one implementation, the sides of the first and second parts facing away from the cover plate are flush.

[0045] By adopting the above-mentioned configuration, this application can avoid the protruding part of the substrate from scratching the devices in the mounting cavity of the power case, and can make the outer surface of the two-phase heat sink more regular, which can simplify the installation process and facilitate mechanical fixation (such as clamping). Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the structure of a photovoltaic system provided in an embodiment of this application;

[0047] Figure 2 This is a schematic diagram of the power conversion device provided in the embodiments of this application;

[0048] Figure 3 This is one of the structural schematic diagrams of a two-phase heat sink provided in the embodiments of this application;

[0049] Figure 4 This is a second schematic diagram of the structure of a two-phase heat sink provided in an embodiment of this application;

[0050] Figure 5 for Figure 4 A cross-sectional view of a two-phase radiator in the image;

[0051] Figure 6 for Figure 4 One of the structural diagrams of the evaporator in the image;

[0052] Figure 7 This is one of the structural schematic diagrams of the substrate and protrusion structure provided in the embodiments of this application;

[0053] Figure 8 This is a second schematic diagram of the substrate and protrusion structure provided in the embodiments of this application;

[0054] Figure 9 for Figure 4One of the schematic diagrams of a partial structure of the evaporator in the image;

[0055] Figure 10 for Figure 4 The second schematic diagram of the partial structure of the evaporator in the diagram;

[0056] Figure 11 for Figure 4 The third schematic diagram of the partial structure of the evaporator in the diagram;

[0057] Figure 12 for Figure 4 The fourth schematic diagram of the partial structure of the evaporator in the diagram;

[0058] Figure 13 for Figure 4 The second schematic diagram of the evaporator structure in the image;

[0059] Figure 14 for Figure 4 One of the structural schematic diagrams of the evaporator and part of the condenser in the image;

[0060] Figure 15 for Figure 4 The second schematic diagram of the evaporator and part of the condenser in the diagram;

[0061] Figure 16 for Figure 4 The third schematic diagram of the evaporator structure in the diagram;

[0062] Figure 17 for Figure 4 The fourth schematic diagram of the evaporator structure in the diagram;

[0063] Figure 18 for Figure 4 The third schematic diagram of the evaporator and part of the condenser in the diagram;

[0064] Figure 19 for Figure 4 The fourth schematic diagram of the evaporator and part of the condenser in the diagram;

[0065] Figure 20 for Figure 4 Fifth schematic diagram of the evaporator and part of the condenser in the diagram;

[0066] Figure 21 for Figure 4 The sixth schematic diagram of the structure of the evaporator and part of the condenser.

[0067] Figure label:

[0068] 01-Photovoltaic system; 100-Power conversion device; 100A-Photovoltaic inverter; 100B-Energy storage converter; 200-Photovoltaic module; 300-Transformer; 400-Energy storage battery; 500-Grid;

[0069] 10-Power housing; 11-Mounting cavity; 12-Opening;

[0070] 21-Circuit board; 22-Heating device;

[0071] 30-Two-phase radiator; 31-Evaporator; 311-Baseboard; 3111-First part; 31111-First mounting plate; 31112-Second mounting plate; 31113-Receiving cavity; 31114-First capillary liquid absorption structure; 31115-Second capillary liquid absorption structure; 3112-Second part; 31121-Opening; 31122-Stepped hole; 311221-First sub-hole; 311222-Second sub-hole; 312-Cover plate; 313-Evaporation cavity; 314-Reinforcing rib; 315-Protruding structure; 316-Screw; 317-Sealing ring; 32-Condenser; 321-Flat tube fin; 3211-Flat tube hole; 322-Secondary fin; 323-Condensation cavity; 33-Gas pipe; 34-Liquid pipe;

[0072] 40 - Heat sink;

[0073] 50 - Thermal conductive layer. Detailed Implementation

[0074] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0075] The terms "first," "second," and similar terms used herein do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms "a" or "one," and similar terms, do not indicate a quantity limitation, but rather indicate the presence of at least one. Furthermore, in the description of the embodiments in this application, unless otherwise stated, "multiple" means two or more.

[0076] Figure 1This is a schematic diagram of the structure of a photovoltaic system 01 provided in an embodiment of this application. The photovoltaic system 01 includes a power conversion device 100, a photovoltaic module 200, a transformer 300, and an energy storage battery 400. The power conversion device 100 provided in this application can be a photovoltaic inverter 100A or a power conversion system (PCS) 100B. The photovoltaic inverter 100A is used to convert the direct current generated by the photovoltaic module 200 into alternating current and supply it to the transformer 300. The transformer 300 is used to boost the alternating current output by the photovoltaic inverter 100A and then supply it to the power grid 500.

[0077] Similarly, the energy storage inverter 100B converts the direct current (DC) output from the energy storage battery 400 into alternating current (AC) and supplies it to the transformer 300. The transformer 300 then boosts the AC output from the energy storage inverter 100B before supplying it to the grid 500. Unlike the photovoltaic inverter 100A, when the electricity price on the grid 500 is low, the energy storage inverter 100B can also convert the AC power from the grid 500 into DC power to charge the energy storage battery 400.

[0078] The specific structure of the power conversion device 100 provided in this application will be described below.

[0079] Figure 2 This is a schematic diagram of the structure of the power conversion device 100 provided in the embodiments of this application, as shown below. Figure 2 As shown, the power conversion device 100 includes a power housing 10, a circuit board 21, a heat-generating device 22, and a two-phase heat sink 30.

[0080] The power housing 10 has a mounting cavity 11 and an opening 12 communicating with the mounting cavity 11. The mounting cavity 11 is used to house the circuit board 21 and the heating element 22, and the heating element 22 is fixed to the circuit board 21. The opening 12 is used to allow the two-phase heat sink 30 to be exposed from inside the mounting cavity 11.

[0081] The two-phase heat sink 30 covers the opening 12 of the power housing 10 and is fixed to the power housing 10. In this application, the two-phase heat sink 30 is at least partially located outside the power housing 10, and one side of the two-phase heat sink 30 is fixed to the side of the heat-generating device 22 facing away from the circuit board 21. For example, a portion of the two-phase heat sink 30 is located inside the mounting cavity 11 of the power housing 10, and another portion is located outside the power housing 10; or, as... Figure 2 As shown, all two-phase heat sinks 30 are located outside the power housing 10, and one side of the two-phase heat sinks 30 is exposed through the opening 12 of the power housing 10 (i.e., one side of the two-phase heat sinks 30 can be seen from inside the mounting cavity 11).

[0082] In this application, the side of the two-phase radiator 30 exposed from the opening 12 is the evaporator 31 of the two-phase radiator 30. Figure 2 (Not shown, but will be described in detail below) one side.

[0083] In addition, to ensure the sealing performance of the power cavity, a sealing ring is provided between the two-phase heat sink 30 and the power housing 10. The sealing ring improves the sealing level of the power housing 10 and prevents moisture from the external environment from affecting the circuit board 21 or components inside the power housing 10.

[0084] For example, the power conversion device 100 of this application also includes a heat sink 40, which is fixed to one side of the power housing 10. At least a portion of the two-phase heat sink 30 is located inside the heat sink 40, and the heat sink 40 has an air inlet and an air outlet communicating with the external environment. In addition, a cooling fan may be provided inside the heat sink 40 to dissipate heat and cool the condenser 32 of the two-phase heat sink 30, thereby increasing the condensation rate and accelerating the two-phase conversion of the two-phase heat sink 30.

[0085] Alternatively, in some other embodiments, the power conversion device 100 may not have a heat sink 40, and the condenser 32 of the two-phase heat sink 30 may be directly exposed to the external environment, using the cold air in the external environment for heat dissipation and cooling.

[0086] Figure 3 This is one of the structural schematic diagrams of the two-phase heat sink 30 provided in the embodiments of this application. Figure 4 This is the second schematic diagram of the structure of the two-phase radiator 30 provided in the embodiments of this application. Figure 5 for Figure 4 A cross-sectional view of the two-phase radiator 30, in conjunction with reference to Figures 3 to 5 As shown, the two-phase radiator 30 includes an evaporator 31 and a condenser 32, with the evaporator 31 and the condenser 32 connected together.

[0087] The two-phase radiator 30 of this application can be as follows: Figure 3 The split type shown can also be as follows: Figure 4 and Figure 5 The integrated type shown (e.g., evaporator 31 and condenser 32 welded together) should be selected according to the specific application requirements. When the two-phase radiator 30 is a separate type, such as... Figure 3As shown, the two-phase radiator 30 also includes a gas pipe 33 and a liquid pipe 34. One end of both the gas pipe 33 and the liquid pipe 34 is connected to the evaporator 31, and the other end is connected to the condenser 32. The two-phase cooling medium is heated and boils into a gaseous state in the evaporator 31 by the high-heat-dissipation heating element 22. The gaseous two-phase cooling medium then flows upward through the gas pipe 33 into the condenser 32. Under the influence of an external airflow, the gaseous two-phase cooling medium condenses upon contact with the condenser. The condensed liquid two-phase cooling medium flows back into the evaporator 31 under gravity through the liquid pipe 34 to continue being heated and boiling, thus completing the cycle.

[0088] When the two-phase radiator 30 is a single unit, combined with Figure 4 and Figure 5 As shown, the condenser 32 of the two-phase radiator 30 includes multiple flat tube fins 321 and a condensing chamber 323. The condensing chamber 323 is located on the side of the multiple flat tube fins 321 away from the evaporator 31. The flat tube fins 321 have flat tube holes 3211, one end of which connects to the evaporation chamber 313 of the evaporator 31, and the other end of which connects to the condensing chamber 323. The condenser 32 of the two-phase radiator 30 may also include secondary fins 322, which are connected between two adjacent flat tube fins 321 to increase the heat exchange area between the condenser 32 and the air. After the two-phase cooling medium is heated and boiled into a gaseous state by the high-heat-dissipation heating device 22 in the evaporation chamber 313, the gaseous two-phase cooling medium enters the flat tube hole 3211 and condenses upon cooling. After condensation, part of the liquid two-phase cooling medium flows back into the evaporation chamber 313, and the other part enters the condensation chamber 323 and then merges with the liquid two-phase cooling medium in the evaporation chamber 313 through the flat tube hole 3211 and continues to be heated and boiled, thus circulating.

[0089] For example, this application does not limit the specific placement of the condenser 32 and evaporator 31 in their operating state. For instance, in some embodiments, such as Figure 3 As shown, the condenser 32 is located above the evaporator 31, which facilitates the return of the liquid two-phase cooling medium to the evaporation chamber 313 under gravity; or, as... Figure 5 As shown, the condenser 32 and the evaporator 31 are arranged horizontally side by side. This arrangement can reduce the space occupied by the two-phase radiator 30 and improve space utilization. Alternatively, the condenser 32 and the evaporator 31 can be placed at an angle. This arrangement can also rely on gravity to facilitate the reflux of the two-phase cooling medium.

[0090] Additionally, when the two-phase radiator 30 is a single unit, the axial direction of the flat tube hole 3211 and the arrangement direction of the evaporator cavity 313 and the condenser cavity 323 can be as follows: Figure 5It can be vertical or non-vertical. For example, the axial direction of the flat tube hole 3211 is not perpendicular to the arrangement direction of the evaporation chamber 313 and the condensation chamber 323. For instance, the end of the flat tube hole 3211 that connects to the evaporation chamber 313 is higher than the end of the flat tube hole 3211 that connects to the condensation chamber 323. This facilitates the reflux of the condensed liquid working fluid.

[0091] In this application, the evaporator 31 covers the opening 12 of the power housing 10 and is fixedly connected to the power housing 10, which facilitates the fixing of one side of the evaporator 31 to the heating device 22.

[0092] Figure 6 for Figure 4 One of the structural schematic diagrams of the evaporator 31 in the diagram, combined with Figure 4 and Figure 6 As shown, the evaporator 31 includes a substrate 311 and a cover plate 312. The substrate 311 is located between the cover plate 312 and the heating element 22 and is connected to the heating element 22. The substrate 311 is connected to the cover plate 312 and together with the cover plate 312 forms the aforementioned evaporation chamber 313. The evaporation chamber 313 contains the aforementioned two-phase cooling medium, which can be used to absorb the heat generated by the heating element 22 and undergo a phase change cycle between the evaporator 31 and the condenser 32.

[0093] For example, the cover plate 312 can be obtained by stamping, so that the evaporation cavity 313 formed by the substrate 311 and the cover plate 312 is the stamping cavity of the cover plate 312.

[0094] In the power conversion device 100 of this application, by connecting the substrate 311 in the evaporator 31 of the two-phase radiator 30 to the heating device 22, the two-phase cooling working fluid located in the evaporation cavity 313 formed by the substrate 311 and the cover plate 312 can absorb the heat of the heating device 22 and undergo a phase change (conversion between liquid and gas). The heat of the heating device 22 is carried away by the extremely high latent heat of vaporization, so as to achieve a heat transfer efficiency far exceeding that of traditional air cooling and single-phase liquid cooling.

[0095] The substrate 311 and the cover plate 312 can be fixed by welding, fastening, or screws. However, regardless of the method used, the sealing performance of the evaporation chamber 313 formed by the substrate 311 and the cover plate 312 must be ensured to reduce the risk of leakage.

[0096] For example, the side of the substrate 311 facing the cover plate 312 has a reinforcing rib 314. One end of the reinforcing rib 314 is connected to the substrate 311 and the other end is connected to the cover plate 312. By providing the reinforcing rib 314, the structural strength of the evaporator 31 can be improved, the risk of deformation of the evaporator 31 under high temperature can be reduced, and the working reliability of the evaporator 31 can be improved.

[0097] For example, combined Figure 5 and Figure 6 As shown, the substrate 311 includes a first portion 3111 and a second portion 3112, the first portion 3111 and the second portion 3112 being adjacent to each other along a thickness direction perpendicular to the substrate 311, the thickness direction of the substrate 311 corresponding to... Figure 5 The directions shown are horizontal, corresponding to... Figure 6 The orientation shown is the vertical direction. The direction perpendicular to the thickness of substrate 311 refers to... Figure 5 The vertical direction in the indicated orientation and Figure 6 The horizontal direction is shown in the diagram. The first part 3111 and the second part 3112 being adjacent along the thickness direction perpendicular to the substrate 311 means that the substrate 311 is divided into the first part 3111 and the second part 3112, the first part 3111 and the second part 3112 are adjacent along the thickness direction perpendicular to the substrate 311, and the first part 3111 and the second part 3112 are contiguous in the thickness direction perpendicular to the substrate 311.

[0098] The heating element 22 is connected to the first part 3111, which is made of copper, and the second part 3112 is made of aluminum.

[0099] For example, the first portion 3111 may include one or more, and the number of first portions 3111 may be determined according to the number of heat-generating devices 22 that need to dissipate heat. The area of ​​the substrate 311 other than the first portion 3111 is the second portion 3112.

[0100] Furthermore, the projected area of ​​the first portion 3111 along the thickness direction of the substrate 311 can be greater than or equal to the projected area of ​​the heat-generating device 22 along the thickness direction of the substrate 311. For example, when there is only one first portion 3111 and it is used to dissipate heat for multiple heat-generating devices 22 simultaneously, the projected area of ​​the first portion 3111 along the thickness direction of the substrate 311 is greater than the projected area of ​​the heat-generating device 22 along the thickness direction of the substrate 3111; when there are multiple first portions 3111 and each first portion 3111 is used to dissipate heat for one heat-generating device 22, the projected area of ​​the first portion 3111 along the thickness direction of the substrate 311 is equal to or slightly greater than the projected area of ​​the corresponding heat-generating device 22 along the thickness direction of the substrate 3111.

[0101] Because this application uses copper, which has a high thermal conductivity, as the material of the first part 3111 connected to the heating device 22, and aluminum as the material of the part of the substrate 311 not connected to the heating device 22 (i.e., the second part 3112), the copper first part 3111 can quickly introduce and spread the heat transferred by the heating device 22 laterally, reducing the thermal resistance (thermal resistance of longitudinal heat transfer) and diffusion resistance (thermal resistance of lateral heat transfer) of the two-phase cooling medium from the heating device 22 to the evaporation chamber 313, the heat is quickly transferred to the two-phase cooling medium. The rapid introduction of heat causes the two-phase cooling medium to activate nucleation boiling earlier and more violently, and the bubbles are generated more frequently and detached faster per unit area. This avoids local overheating caused by heat accumulation under the heating device 22, reduces the risk of the two-phase cooling medium being burned dry in high heat flux density scenarios, and improves the heat dissipation limit and reliability of the two-phase heat sink 30 in high heat flux density scenarios.

[0102] In addition, the first part 3111 connected to the heat-generating device 22 is made of copper, while the second part 3112 is made of aluminum. Copper, which is more expensive, is used in local areas with high heat flow, while aluminum, which is lighter and cheaper, is used in areas with low heat load. This avoids the expensive material cost of using a full copper substrate 311 and also reduces the overall weight. This allows the present application to optimize the manufacturing cost of the heat sink while ensuring heat dissipation performance, and achieves a better balance between heat dissipation performance and cost.

[0103] Continue to refer to Figure 6 In one implementation, the first part 3111 has a plurality of spaced protrusions 315 on the side facing the cover plate 312, and the plurality of protrusions 315 are located in the evaporation chamber 313.

[0104] For example, Figure 7 This is one of the structural schematic diagrams of the substrate 311 and the protrusion structure 315 provided in the embodiments of this application, such as... Figure 7 As shown, the multiple protruding structures 315 can be multiple columnar protrusions, or needle fins (i.e., needle-shaped fins), which can be manufactured by stamping or forging; or, Figure 8 This is a second schematic diagram of the structure of the substrate 311 and the protrusion structure 315 provided in the embodiments of this application, as shown below. Figure 8 As shown, the multiple protrusions 315 can be multiple parallel, thin and tall sheet-like protrusions, or dense tooth structure (i.e., a structure formed by multiple heat dissipation fins). The dense tooth structure can be formed by CNC machining or other methods.

[0105] Furthermore, this application does not limit the arrangement of the multiple protrusions 315; they can be arranged randomly, linearly, or in an array, etc.

[0106] The height of the protruding structure 315 can be determined according to actual needs. For example, the end of the protruding structure 315 facing the cover plate 312 can extend to and connect with the cover plate 312, or the end of the protruding structure 315 facing the cover plate 312 can have a gap with the cover plate 312. Figure 6 The illustration is based on the example where the end of the protruding structure 315 facing the cover plate 312 has a gap with the cover plate 312.

[0107] This application, by setting multiple protruding structures 315, can increase the effective contact heat exchange area between the substrate 311 and the two-phase cooling medium in the evaporation chamber 313, so that heat can be absorbed and carried away by the medium more efficiently and evenly, thereby improving the heat dissipation capacity and the upper limit of the heat flux density that the two-phase radiator 30 can withstand. In addition, the multiple protruding structures 315 can also play a mechanical support role between the cover plate 312 and the substrate 311. The multiple protruding structures 315 can separate and reinforce the evaporation chamber 313, resisting the deformation or vibration of the evaporator 31 caused by the phase change of the two-phase cooling medium and pressure fluctuations, enhancing the overall structural strength and long-term operational reliability of the evaporator 31, and ensuring the structural integrity and performance stability of the two-phase radiator 30 under high load and high pressure differential conditions.

[0108] Figure 9 for Figure 4 One of the partial structural diagrams of the evaporator 31 in the diagram. Figure 10 for Figure 4 The second schematic diagram of the partial structure of the evaporator 31 in the diagram is as follows: Figure 9 or Figure 10 As shown, in one implementation, the outer wall surface of the protrusion structure 315 has an uneven texture.

[0109] The outer wall surface of the raised structure 315 has an uneven texture, or it can be considered that the outer wall surface of the raised structure 315 has a microstructure surface, which means that the outer wall surface of the raised structure 315 is pitted and uneven.

[0110] For example, the uneven textured outer wall surface of the raised structure 315 can be obtained by additive or subtractive manufacturing processes. For instance, the outer wall surface of the raised structure 315 can be treated with copper powder sintering, laser processing, or sandblasting. Figure 9 This is the structure obtained after additive manufacturing of the outer wall surface of the protruding structure 315. Figure 9 The outer wall surface of the protruding structure 315 in the middle has many protrusions after the additive manufacturing process; Figure 10 The structure is obtained by subtractive processing of the outer wall surface of the protruding structure 315. Figure 10 The outer wall surface of the protruding structure 315 in the middle has many grooves after the material reduction process.

[0111] This application forms an uneven, textured structure on the outer wall of the raised structure 315 using additive or subtractive manufacturing processes. This structure increases the actual contact area with the two-phase cooling medium, providing a large number of stable vaporization nuclei. This promotes the rapid generation, growth, and detachment of bubbles in the two-phase cooling medium when heated, enhancing the boiling heat transfer intensity of the two-phase cooling medium in the evaporation chamber 313. As a result, the evaporator 31 can more efficiently stimulate the phase change heat transfer of the two-phase cooling medium when dealing with transient peak power, improving the heat dissipation limit and reliability of the two-phase radiator 30 in high heat flux density scenarios.

[0112] Figure 11 for Figure 4 The third schematic diagram of the partial structure of the evaporator 31 in the diagram. Figure 12 for Figure 4 The fourth schematic diagram of the partial structure of the evaporator 31 in the diagram is as follows: Figure 11 or Figure 12 As shown, in one implementation, the side of the first part 3111 facing the cover plate 312 has an uneven texture.

[0113] in, Figure 11 The structure shown is obtained by additive processing on the side of the first part 3111 facing the cover plate 312. After additive processing, the side of the first part 3111 facing the cover plate 312 has many protrusions. Figure 12 The diagram shows the structure obtained by subtracting material from the side of the first part 3111 facing the cover plate 312. After the subtraction process, the side of the first part 3111 facing the cover plate 312 forms many grooves. The methods of additive and subtractive processing can be referred to the previous text and will not be repeated here.

[0114] The uneven texture of the first part 3111 facing the cover plate 312 is the same as the uneven texture of the outer wall of the raised structure 315. It also enhances nucleation boiling through the uneven texture structure, so that the evaporator 31 can more efficiently stimulate the phase change heat of the working fluid, thereby improving the heat dissipation performance of the two-phase radiator 30 in high heat flux density scenarios.

[0115] Additionally, the side of the second part 3112 facing the cover plate 312 can also be processed by additive or subtractive manufacturing to obtain an uneven textured structure. The uneven textured structure can be provided in at least one or more of the first part 3111, the second part 3112, and the protrusion structure 315.

[0116] Figure 13 for Figure 4 The second schematic diagram of the structure of the evaporator 31 in the diagram. Figure 14 for Figure 4 One of the structural schematic diagrams of the evaporator 31 and part of the condenser 32 in the diagram. Figure 15 for Figure 4 The second schematic diagram of the structure of the evaporator 31 and part of the condenser 32 is shown in the figure. Figure 13 , Figure 14 or Figure 15 As shown, in one implementation, the first part 3111 is a vacuum chamber heat sink (VC), or simply a VC heat sink.

[0117] The VC heat sink includes a first mounting plate 31111 and a second mounting plate 31112. The first mounting plate 31111 is located on the side of the second mounting plate 31112 opposite to the cover plate 312 and is connected to the heat-generating device 22. The second mounting plate 31112 is connected to the first mounting plate 31111 and forms a receiving cavity 31113 with it, and the receiving cavity 31113 contains a liquid working fluid. The side of the first mounting plate 31111 facing the second mounting plate 31112 has a first capillary liquid absorption structure 31114, and the side of the second mounting plate 31112 facing the first mounting plate 31111 has a second capillary liquid absorption structure 31115. The first capillary liquid absorption structure 31114 and the second capillary liquid absorption structure 31115 are used to transfer the heat of the heat-generating device 22 from the first mounting plate 31111 through the second mounting plate 31112 to the two-phase cooling working fluid through the phase change cycle of the liquid working fluid.

[0118] The aforementioned receiving cavity 31113 is a vacuum cavity.

[0119] When the heat from the heating device 22 is conducted to the first mounting plate 31111, the liquid working fluid in the receiving cavity 31113 rapidly absorbs heat and evaporates at the first capillary liquid absorption structure 31114. The vapor diffuses into the cavity to the second mounting plate 31112, which has a lower temperature. The vapor condenses and releases latent heat on the surface of the second capillary liquid absorption structure 31115 at the second mounting plate 31112. The heat is then transferred to the two-phase cooling working fluid. The condensed liquid working fluid, relying on the capillary force generated by the combined action of the first capillary liquid absorption structure 31114 and the second capillary liquid absorption structure 31115, quickly flows back to the first mounting plate 31111, thereby completing a continuous and efficient heat transfer cycle.

[0120] The first part 3111 of this application employs a VC heat sink. The VC heat sink, with its internal two-phase circulation mechanism, provides a lateral equivalent thermal conductivity far exceeding that of solid metals. This reduces the diffusion thermal resistance from the high heat flux density heating element 22 to the entire evaporator 31, allowing the heat generated by the heating element 22 to be instantaneously and more evenly diffused throughout the evaporation chamber 313, improving thermal uniformity and reducing heat flux density. This temperature uniformity reduces local hot spots generated by the heating element 22, enabling the two-phase cooling medium within the evaporation chamber 313 to undergo a more intense and uniform boiling phase change over a wider range. This improves the overall heat dissipation capacity of the two-phase heat sink 30 and its reliability in responding to transient power surges. Furthermore, the flat package structure of the VC heat sink facilitates integration with the second part 3112, contributing to a compact design of the evaporator 31.

[0121] In addition, besides using the VC heatsink structure, the first part 3111 can also use a structure of multiple square heat pipes instead. That is, the first structure can include multiple heat pipes, each heat pipe has a square cross-section, and adjacent heat pipes are connected.

[0122] When the first part 3111 uses a VC heatsink, the side of the first part 3111 facing the cover plate 312 can also be as follows: Figure 13 The diagram shows a protruding structure 315, which can be as follows: Figure 14 The needle FIN structure shown can also be Figure 15 The aforementioned close-tooth structure.

[0123] The substrate 311 may have a through hole. The first part 3111 is disposed in the through hole, and the part of the substrate 311 without the through hole is the second part 3112. The optional methods of the through hole will be described below.

[0124] (1) The first type of through hole in substrate 311: Figure 16 for Figure 4 The third schematic diagram of the evaporator 31 in the diagram is as follows: Figure 16 As shown, the substrate 311 has an opening 31121 (i.e., a through hole) that extends through the thickness direction of the substrate 311. The radial dimension of the opening 31121 remains unchanged along the thickness direction of the substrate 311.

[0125] With the radial dimension of the opening 31121 remaining constant, for example, a first portion 3111 is disposed within the opening 31121, and the outer wall of the first portion 3111 is welded (e.g., soldered) to the inner wall of the opening 31121. Fixing the first portion 3111 and the second portion 3112 by welding provides a reliable structure and avoids the introduction of external connection structures, simplifying the connection method. In another example, when the radial dimension of the opening 31121 remains constant, the first portion 3111 and the second portion 3112 can also be fixed by screws or adhesive.

[0126] (2) The second method of through hole in substrate 311: Figure 17 for Figure 4 The fourth schematic diagram of the evaporator 31 in the diagram is shown below. Figure 17 As shown, in one implementation, the substrate 311 has a stepped hole 31122 (i.e., a through hole is the stepped hole 31122) extending through the thickness direction of the substrate 311; the stepped hole 31122 includes a first sub-hole 311221 and a second sub-hole 311222 communicating in the thickness direction of the substrate 311. The first sub-hole 311221 is located on the side of the second sub-hole 311222 facing away from the evaporation chamber 313, and the radial dimension of the first sub-hole 311221 is larger than the radial dimension of the second sub-hole 311222. A portion of the first portion 3111 is located within the first sub-hole 311221, and another portion of the first portion 3111 is located within the second sub-hole 311222.

[0127] In this part, the portion of the first part 3111 located inside the first sub-hole 311221 contacts the stepped surface of the first sub-hole 311221 (i.e., the bottom wall of the first sub-hole 311221, or the connecting surface between the inner wall of the first sub-hole 311221 and the inner wall of the second sub-hole 311222). The stepped surface of the first sub-hole 311221 can limit the first part 3111 when it is assembled in the second part 3112.

[0128] This application provides a stepped hole 31122 with a first sub-hole 311221 and a second sub-hole 311222, and places a portion of the first part 3111 within the first sub-hole 311221 and another portion of the first part 3111 within the second sub-hole 311222. In this way, when assembling the second part 3112 and the first part 3111, the first sub-hole 311221 and the second sub-hole 311222 with different radial dimensions can cooperate with the first part 3111 to limit the assembly of the first part 3111, which facilitates the positioning of the first part 3111 and the second part 3112.

[0129] When the through hole is a stepped hole 31122, the first part 3111 and the second part 3112 can be fixed by welding. For example, the portion of the first part 3111 located inside the first sub-hole 311221 can be welded to the inner wall of the first sub-hole 311221, and the portion of the first part 3111 located inside the second sub-hole 311222 can be welded to the inner wall of the second sub-hole 311222; or, the first part 3111 and the second part 3112 can also be fixed by screws 316. For example, the portion of the first part 3111 located inside the first sub-hole 311221 can be fixed to the second part 3112 by screws 316, and the portion of the first part 3111 located inside the second sub-hole 311222 can be sealed to the inner wall of the second sub-hole 311222 by a sealing ring 317.

[0130] This application uses screws 316 to fix the first part 3111 and the second part 3112, which facilitates the disassembly and installation of the first part 3111 and the second part 3112. If the first part 3111 or the second part 3112 is damaged and needs to be replaced, the corresponding part can be replaced by removing the screws 316. The sealing ring 317 improves the sealing performance of the evaporation chamber 313 and prevents leakage.

[0131] Additionally, to prevent the first part 3111 from scratching the components inside the mounting cavity 11 of the power housing 10, in one implementation, such as Figure 17 As shown, the sides of the first part 3111 and the second part 3112 facing away from the cover plate 312 are flush. That is, the side of the substrate 311 facing away from the cover plate 312 is a plane.

[0132] In addition, the flush first part 3111 and the second part 3112 can make the outer surface of the two-phase radiator 30 more regular, which can simplify the installation process, facilitate mechanical fixing (such as clamping), and apply uniform pressure, thereby ensuring the stability and reliability of the thermal interface during long-term operation.

[0133] Figure 18 for Figure 4 The third schematic diagram of the structure of the evaporator 31 and part of the condenser 32. Figure 19 for Figure 4 The fourth schematic diagram of the structure of the evaporator 31 and part of the condenser 32 is shown in one implementation, such as... Figure 18 or Figure 19 As shown, the side of the first part 3111 facing the heating device 22 is in contact with and welded to the heating device 22.

[0134] This application welds the heating element 22 to the first part 3111, so that the heat generated by the heating element 22 can be directly transferred to the first part 3111 of the evaporator 31, reducing the contact thermal resistance on the heat transfer path and improving the heat transfer efficiency.

[0135] Figure 20 for Figure 4 The fifth schematic diagram of the structure of the evaporator 31 and part of the condenser 32 is shown. Figure 21 for Figure 4 The sixth schematic diagram of the structure of the evaporator 31 and part of the condenser 32 is shown in Figure 6. Figure 20 or Figure 21 As shown, in another implementation, the two-phase heat sink 30 further includes a heat-conducting layer 50, wherein the heat-conducting layer 50 is disposed on the side of the first part 3111 facing the heat-generating device 22, and the first part 3111 is connected to the heat-generating device 22 through the heat-conducting layer 50.

[0136] The thermally conductive layer 50 is a thermal interface material (TIM) layer, such as thermal grease, phase change material, or thermal pad. By filling the microscopic air gaps between the heating device 22 and the first part 3111 caused by surface unevenness, the thermally conductive layer 50 can eliminate the insulation effect caused by the air layer, reduce the interfacial contact thermal resistance, and thus establish an efficient heat conduction path.

[0137] In addition, the thermally conductive layer 50 has a certain degree of flexibility and compressibility, which can adapt to the slight height difference or deformation that may exist between the heating device 22 and the substrate 311, ensuring a uniform distribution of contact pressure and avoiding overheating caused by poor local contact. Furthermore, the thermally conductive layer 50 can also act as a buffer for mechanical stress, reducing potential mechanical damage to the heating device 22 caused by differences in thermal expansion coefficients and fastening pressure.

[0138] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples. The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A power conversion device, characterized by, The power shell, the heat generating device, and a two-phase heat sink are included; wherein: The power shell has a mounting cavity for accommodating the heat generating device and an opening communicating with the mounting cavity; The two-phase heat sink includes an evaporator and a condenser, and the evaporator is in communication with the condenser; The evaporator covers the opening and is fixedly connected with the power shell, and the evaporator includes a base plate and a cover plate, the base plate is located between the cover plate and the heat generating device and is connected with the heat generating device, the base plate is connected with the cover plate and encloses the evaporator cavity, the two-phase cooling working medium is arranged in the evaporator cavity, the two-phase cooling working medium is used for absorbing the heat generated by the heat generating device and circulating in the phase change between the evaporator and the condenser; The base plate includes a first part and a second part, the first part and the second part are adjacent along the thickness direction perpendicular to the base plate, the heat generating device is connected with the first part, the material of the first part is copper, and the material of the second part is aluminum.

2. The power conversion device of claim 1, wherein, One side of the first part facing the cover plate is provided with a plurality of spaced protruding structures, and the plurality of protruding structures are located in the evaporator cavity.

3. The power conversion device of claim 2, wherein, The outer wall surface of the protruding structure is in a concave-convex texture shape.

4. A power conversion device according to any one of claims 1-3, characterized in that One side of the first part facing the cover plate is in a concave-convex texture shape.

5. The power conversion device according to any one of claims 1 to 4, characterized by, The first part includes a first mounting plate and a second mounting plate, wherein: The first mounting plate is located on the side of the second mounting plate away from the cover plate and is connected with the heat generating device; The second mounting plate is connected with the first mounting plate and encloses the accommodation cavity, and the liquid working medium is arranged in the accommodation cavity; One side of the first mounting plate facing the second mounting plate has a first capillary liquid suction structure, and one side of the second mounting plate facing the first mounting plate has a second capillary liquid suction structure; The first capillary liquid suction structure and the second capillary liquid suction structure are used for transmitting the heat of the heat generating device from the first mounting plate to the two-phase cooling working medium through the second mounting plate by the phase change circulation of the liquid working medium.

6. The power conversion device of any one of claims 1-5, wherein, The base plate has an opening hole penetrating through the thickness direction of the base plate; The first part is arranged in the opening hole, and the outer wall of the first part is welded with the inner wall of the opening hole; The part of the base plate without the opening hole serves as the second part.

7. A power conversion device according to any one of claims 1-5, characterized in that The base plate has a stepped hole penetrating through the thickness direction of the base plate; the first part is arranged in the stepped hole, and the part of the base plate without the stepped hole serves as the second part; The stepped hole includes a first sub-hole and a second sub-hole in communication in the thickness direction of the base plate, the first sub-hole is located on the side of the second sub-hole away from the evaporator cavity, and the radial size of the first sub-hole is greater than that of the second sub-hole; Part of the first part is located in the first sub-hole and contacts with the stepped surface of the stepped hole, and the other part of the first part is located in the second sub-hole.

8. The power conversion device of claim 7, wherein, The part of the first part located in the first sub-hole is fixed with the second part by a screw, and the part of the first part located in the second sub-hole is sealingly connected with the inner wall of the second sub-hole by a sealing ring. Alternatively, the portion of the first portion located in the first sub-hole is welded to the inner wall of the first sub-hole, and the portion of the first portion located in the second sub-hole is welded to the inner wall of the second sub-hole.

9. The power conversion device of any of claims 1-8, wherein, One side of the first portion facing the heat generating device is welded to the heat generating device.

10. The power conversion device of any one of claims 1-8, wherein, The two-phase heat sink further comprises a heat-conducting layer, wherein: The heat-conducting layer is arranged on the side of the first portion facing the heat generating device, and the first portion is connected to the heat generating device through the heat-conducting layer.

11. A two-phase heat spreader, comprising: It comprises an evaporator and a condenser, wherein: The evaporator is in communication with the condenser; The evaporator comprises a base plate and a cover plate, one side of the base plate away from the cover plate is used to connect with the heat generating device, the base plate connects the cover plate and encloses the cover plate to form an evaporation cavity; the evaporation cavity is provided with a two-phase cooling working medium, which is used to absorb the heat generated by the heat generating device and circulate between the evaporator and the condenser; the base plate comprises a first portion and a second portion, the first portion and the second portion are adjacent along the thickness direction perpendicular to the base plate, the first portion is used to connect with the heat generating device, the material of the first portion is copper, and the material of the second portion is aluminum. One side of the first portion facing the cover plate is provided with a plurality of spaced protruding structures, and the plurality of protruding structures are located in the evaporation cavity.

12. The two-phase heat spreader of claim 11, wherein, The outer wall surface of the protruding structure is in a concave-convex texture shape.

13. The two-phase heat spreader of claim 12, wherein, The side of the first portion facing the cover plate is in a concave-convex texture shape.

14. The two-phase heat spreader of any of claims 11-13, wherein, The first portion comprises a first mounting plate and a second mounting plate, wherein:

15. The two-phase heat spreader of any of claims 11-14, wherein, The first mounting plate is located on the side of the second mounting plate away from the cover plate and is used to connect with the heat generating device; The second mounting plate connects the first mounting plate and encloses the first mounting plate to form a containing cavity, and the containing cavity is provided with a liquid working medium; One side of the first mounting plate facing the second mounting plate has a first capillary liquid suction structure, and one side of the second mounting plate facing the first mounting plate has a second capillary liquid suction structure; The first capillary liquid suction structure and the second capillary liquid suction structure are used to transfer the heat of the heat generating device from the first mounting plate to the two-phase cooling working medium through the phase change cycle of the liquid working medium between them. The base plate has an opening penetrating in the thickness direction of the base plate; 16. The two-phase heat spreader of any of claims 11-15, wherein, The first portion is arranged in the opening, and the outer wall of the first portion is welded to the inner wall of the opening; The portion of the base plate without the opening serves as the second portion. The base plate has a stepped hole penetrating in the thickness direction of the base plate; the first portion is arranged in the stepped hole, and the portion of the base plate without the stepped hole serves as the second portion; 17. The two-phase heat spreader of any of claims 11-15, wherein, The stepped hole comprises a first sub-hole and a second sub-hole in communication in the thickness direction of the base plate, the first sub-hole is located on the side of the second sub-hole away from the evaporation cavity, and the radial size of the first sub-hole is greater than the radial size of the second sub-hole; ​ Part of the first part is located in the first sub-hole and in contact with the stepped surface of the stepped hole, and another part of the first part is located in the second sub-hole.

18. The two-phase heat spreader of claim 17, wherein, The part of the first part located in the first sub-hole is fixed with the second part by a screw, and the part of the first part located in the second sub-hole is sealingly connected with the inner wall of the second sub-hole by a sealing ring. Alternatively, the part of the first part located in the first sub-hole is welded with the inner wall of the first sub-hole, and the part of the first part located in the second sub-hole is welded with the inner wall of the second sub-hole.

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