A power conversion device

Abstract

The application discloses a power conversion device, and belongs to the technical field of heat dissipation. The power conversion device comprises a cavity, a heat exchanger, a condensing assembly, a pump assembly and a preheater. The cavity is configured to accommodate a heat generating device. The heat exchanger is arranged in the cavity and contains a working medium. The heat exchanger is configured to conduct heat in the cavity. The condensing assembly is arranged outside the cavity and connected with an outlet end of the heat exchanger. The pump assembly is connected with an outlet end of the condensing assembly. The preheater is connected with the outlet end of the pump assembly and an inlet end of the heat exchanger, and is configured to preheat the working medium. By arranging the heat exchanger and the preheater in the cavity, the preheated working medium actively absorbs heat in the cavity after entering the heat exchanger and rapidly changes phase, thereby achieving heat dissipation of the environment in the cavity and optimizing heat distribution in a sealed space.

Description

Technical Field

[0001] This application relates to the field of heat dissipation technology, and more particularly to a power conversion device. Background Technology

[0002] In the operation of power devices, external evaporators and condensers are typically required, with a pump driving the circulation of the working fluid to conduct heat generated by the power devices. Power devices are often housed within a sealed cavity, which also contains capacitors, busbars, and other heat-generating components. However, current technologies suffer from low heat dissipation efficiency within this sealed cavity. Utility Model Content

[0003] This application provides a power conversion device aimed at solving the technical problem of low heat dissipation efficiency in a sealed cavity.

[0004] Technical solution: This application provides a power conversion device, including:

[0005] A cavity configured to house a heating device;

[0006] A heat exchanger disposed within the cavity, the heat exchanger containing a working fluid, the heat exchanger being configured to conduct heat within the cavity;

[0007] A condensing assembly is disposed outside the cavity and connected to the outlet end of the heat exchanger;

[0008] A pump assembly connected to the outlet end of the condenser assembly;

[0009] A preheater is connected to the outlet end of the pump assembly and the inlet end of the heat exchanger, and the preheater is configured to preheat the working fluid.

[0010] In some embodiments, the power conversion device further includes:

[0011] A liquid storage tank is disposed outside the cavity and is respectively connected to the outlet end of the condensation assembly and the inlet end of the pump assembly.

[0012] In some embodiments, the power conversion device further includes:

[0013] An evaporator, connected in parallel with the heat exchanger and the preheater, is disposed between the pump assembly and the condenser assembly. The evaporator is configured to conduct heat from the heating element attached to the evaporator to change the working fluid input to the evaporator into gaseous and liquid components.

[0014] In some embodiments, the condensation assembly includes:

[0015] The first condenser has its inlet end connected to the outlet end of the evaporator and the outlet end of the heat exchanger, and is located upstream of the liquid storage tank.

[0016] In some embodiments, the condensation assembly includes:

[0017] A first condenser is disposed between the heat exchanger and the liquid storage tank;

[0018] A second condenser is disposed between the evaporator and the liquid storage tank.

[0019] In some embodiments, the pump assembly includes:

[0020] A first pump, configured to supply working fluid to the evaporator and the preheater;

[0021] In some embodiments, the pump assembly further includes:

[0022] A second pump, which is connected in parallel with the first pump, is configured to supply working fluid to the evaporator and the preheater.

[0023] In some embodiments, the power conversion device further includes:

[0024] A control valve is disposed at the inlet end of the preheater and is configured to control the flow rate of the working fluid supplied to the preheater.

[0025] In some embodiments, the pump assembly includes:

[0026] A first pump is disposed between the liquid storage tank and the preheater;

[0027] A second pump is disposed between the liquid storage tank and the evaporator.

[0028] In some embodiments, the power conversion device further includes a first fan, which is disposed on one side of the condensation assembly;

[0029] Alternatively, the first fan may be positioned between the first condenser and the second condenser.

[0030] In some embodiments, the heat exchanger includes:

[0031] The first manifold is connected to the outlet end of the preheater;

[0032] The second manifold is connected to the inlet end of the condenser assembly;

[0033] Multiple branch pipes are arranged in parallel between the first manifold and the second manifold, and are respectively connected to the first manifold and the second manifold. Multiple fins are provided on the outer wall of each branch pipe. The multiple fins are spaced apart and arranged in an array.

[0034] The power conversion device further includes a second fan, which is disposed within the cavity.

[0035] Beneficial Effects: The power conversion device in this embodiment includes a cavity, a heat exchanger, a condenser assembly, a liquid storage tank, a pump assembly, and a preheater. The cavity is configured to house the heating element. The heat exchanger is disposed within the cavity and contains the working fluid, and is configured to conduct heat within the cavity. The condenser assembly is disposed outside the cavity and connected to the outlet end of the heat exchanger. The pump assembly is connected to the outlet end of the condenser assembly. The preheater is connected to both the outlet end of the pump assembly and the inlet end of the heat exchanger, and is configured to preheat the working fluid. By placing the heat exchanger and preheater within the cavity, the preheated working fluid actively absorbs heat from the cavity after entering the heat exchanger and undergoes a rapid phase change, thereby dissipating heat from the cavity environment and optimizing the heat distribution within the confined space.

[0036] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0039] Figure 1 This is a schematic diagram of the power conversion device according to an embodiment of this application, showing the heat dissipation device.

[0040] Figure 2 This is a schematic diagram of the structure of a power conversion device according to another embodiment of this application;

[0041] Figure 3 This is a schematic diagram of the structure of a power conversion device according to another embodiment of this application;

[0042] Figure 4 This is a schematic diagram of the structure of a power conversion device according to another embodiment of this application;

[0043] Figure 5 This is a schematic diagram of the structure of a power conversion device according to another embodiment of this application;

[0044] Figure 6 This is a schematic diagram of the structure of a power conversion device according to another embodiment of this application;

[0045] Figure 7 This is a schematic diagram of the heat exchanger in the power conversion device according to an embodiment of this application;

[0046] Figure 8 This is a schematic diagram showing the positional relationship between the heat exchanger and the second fan in the power conversion device of this application embodiment.

[0047] Explanation of reference numerals in the attached figures:

[0048] 10. Cavity; 20. Heating element; 30. Heat exchanger; 40. Condensing assembly; 50. Liquid storage tank; 60. Pump assembly; 70. Preheater; 80. Evaporator; 41. First condenser; 42. Second condenser; 61. First pump; 62. Second pump; 90. Control valve; 100. First fan; 31. First manifold; 32. Second manifold; 33. Branch pipe; 34. Fin; 110. Second fan. Detailed Implementation

[0049] 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 a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0050] In the description of this application, it should be understood that the terms "inner," "outer," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. In the description of this application, "multiple" means two or more, and "at least one" can refer to one, two, or more, unless otherwise explicitly specified. The terms "first," "second," etc., are only for the convenience of description and are used to name components or embodiments by number, and do not imply any order of importance between the components or embodiments.

[0051] As a preamble to the embodiments of this application, during the use of power devices, external evaporators and condensers are typically required. A pump drives the circulation of the working fluid to conduct heat generated by the power devices. Power devices are often housed in a sealed cavity, which also contains capacitors, busbars, and other heat-generating components. However, in related technologies, the heat dissipation efficiency within the sealed cavity is low. Power conversion equipment relies on a pump to drive the circulation of the working fluid. The circulating working fluid can dissipate heat from the power devices alone, or simultaneously from both the power devices and the cavity. However, in the latter heat dissipation scheme, the heat inside the cavity is lower than that of the power devices. If working fluids at the same temperature flow through the evaporator and heat exchanger respectively, incomplete evaporation of the working fluid in the heat exchanger will occur, leading to a reduction in heat exchange efficiency.

[0052] In view of this, embodiments of this application provide a power conversion device aimed at solving at least one of the above-mentioned technical problems.

[0053] Please see Figure 1 As shown in the illustration, an embodiment of this application discloses a power conversion device, including a cavity 10, a heat exchanger 30, a condenser assembly 40, a pump assembly 60, and a preheater 70. The cavity 10 is a sealed structure configured to house a heating element 20. The heating element 20 includes power devices, capacitors, inductors, busbars, etc. The cavity 10 is used to fix and protect the heating element 20, isolating it from external dust, water vapor, corrosive gases, and electromagnetic interference, ensuring the reliable operation of precision electronic components. The heat exchanger 30 is disposed within the cavity 10 and contains a working fluid. The heat exchanger 30 is configured to conduct heat within the cavity 10 for the phase change of the working fluid input into the heat exchanger 30. The condenser assembly 40 is disposed outside the cavity 10 and connected to the outlet end of the heat exchanger 30. It is used to re-condense the gaseous working fluid output from the heat exchanger 30 into a liquid state to achieve heat transfer, transferring heat from inside the cavity 10 to outside the cavity 10. The pump assembly 60 is connected to the outlet end of the condenser assembly 40. The preheater 70 is connected to the outlet end of the pump assembly 60 and the inlet end of the heat exchanger 30 respectively. The preheater 70 is configured to preheat the working fluid to near the phase change temperature before the working fluid enters the heat exchanger 30.

[0054] It is important to understand that the air temperature inside the cavity 10 increases as the losses of the heating element 20 increase, and the temperature range inside the cavity 10 is generally between 65℃ and 75℃. By installing a heat exchanger 30 inside the cavity 10, the heat exchanger 30 can actively absorb the heat dissipation and local high temperature in the cavity, thereby reducing heat accumulation inside the cavity 10 and optimizing the heat distribution in the sealed space. By installing a preheater 70, the working fluid can quickly start the phase change after entering the heat exchanger 30, improving the heat exchange efficiency of the working fluid, and at the same time accelerating the response speed of the power conversion equipment to temperature changes inside the cavity 10.

[0055] In some embodiments, the power conversion device further includes a liquid storage tank 50 disposed outside the cavity 10 and connected to the outlet end of the condenser assembly 40 and the inlet end of the pump assembly 60, respectively. The liquid storage tank 50 is used to separate any gaseous working fluid that may remain after condensation by the condenser assembly 40, ensuring that the working fluid entering the downstream pump assembly 60 is a pure liquid, preventing gaseous working fluid from entering the pump body and causing cavitation, protecting the pump assembly 60 and maintaining its delivery efficiency. The liquid storage tank 50 also provides working fluid buffer storage. When the heat load inside the cavity 10 fluctuates, such as changes in the load of the power devices, the output is adjusted to prevent insufficient working fluid supply from causing heat dissipation interruption, or excessive supply from causing abnormal pipeline pressure, ensuring the continuity of the working fluid circulation.

[0056] Please see Figure 1 As shown, in some embodiments, the power conversion device further includes an evaporator 80, which is connected in parallel with the heat exchanger 30 and the preheater 70. The evaporator 80 is disposed between the pump assembly 60 and the condenser assembly 40. The evaporator 80 is configured to conduct heat from the heating element 20 attached to the evaporator 80, thereby changing the phase of the working fluid input to the evaporator 80 into gaseous and liquid components. It should be understood that the evaporator 80 contacts the heating element 20 inside the cavity 10 through attachment (including bonding and embedding) to directionally conduct the heat generated by the heating element 20 to the outside of the cavity 10, thereby ensuring the safety and reliability of the operation of the heating element 20. The evaporator 80 is arranged in parallel with the heat exchanger 30, and the pump assembly 60 provides the working fluid circulation power. Part of the working fluid enters the evaporator 80 and conducts heat with the heating element 20, while part of the working fluid enters the preheater 70 for preheating and is then transferred to the heat exchanger 30 to achieve heat exchange with the cavity 10. Considering the temperature difference between the ambient temperature inside the cavity 10 and the temperature of the heating device 20, the evaporator 80 is also connected in parallel with the preheater 70. The preheater 70 preheats the working fluid flowing through the heat exchanger 30, bringing its temperature close to the phase change temperature, thereby ensuring that the working fluid in the heat exchanger 30 undergoes a complete phase change and improving the heat exchange efficiency.

[0057] Please see Figure 1As shown, in some embodiments, the condensing assembly 40 includes a first condenser 41. The inlet end of the first condenser 41 is connected to the outlet end of the evaporator 80 and the outlet end of the heat exchanger 30, respectively. The first condenser 41 is located upstream of the liquid storage tank 50. It should be understood that the first condenser 41 is used to receive the gas-liquid mixture output from the evaporator 80 and the heat exchanger 30. It cools the working fluid through heat dissipation methods such as air cooling and water cooling, causing the gaseous components in the mixture to condense into liquid components. Simultaneously, it releases the heat absorbed by the working fluid to the external environment. The evaporator 80 and the heat exchanger 30 share the first condenser 41, eliminating the need for separate condensers for the two working fluids. This avoids the increased device size and complex piping caused by multiple condensers in parallel, and also improves the heat exchange efficiency of the condenser through centralized heat release, simplifying the heat release path of the entire power conversion device.

[0058] It should be understood that after the working fluid is condensed by the first condenser 41 and enters the liquid storage tank 50, it needs to undergo another gas-liquid separation in the liquid storage tank 50. The gaseous working fluid flows back to the condenser, while the liquid working fluid is stored in the liquid storage tank 50 or transported to the pump assembly 60 to realize the working fluid circulation.

[0059] Please see Figure 2 As shown, in some embodiments, the condensing assembly 40 includes a first condenser 41 and a second condenser 42. The first condenser 41 is disposed between the heat exchanger 30 and the liquid storage tank 50; the second condenser 42 is disposed between the evaporator 80 and the liquid storage tank 50. By setting independent first condensers 41 and second condensers 42, heat dissipation on demand is achieved. Compared to a single condenser handling two working fluids, using two independent sets of condensers to condense and release heat from working fluids of different heat values ​​ensures heat dissipation while reducing overall energy consumption and unnecessary fan operation and water pump energy consumption. It avoids the thermal interference problem caused by mixing working fluids of different heat values ​​in the same condenser, which leads to obstructed heat release of the high-temperature working fluid and excessive cooling of the low-temperature working fluid, significantly improving the condensation efficiency of the two working fluids and thus ensuring the overall heat transfer efficiency of the entire power conversion equipment.

[0060] Please see Figure 1 and Figure 2 As shown, in some embodiments, pump assembly 60 includes a first pump 61 configured to deliver working fluid to evaporator 80 and preheater 70. It should be understood that the first pump 61 simultaneously delivers working fluid to both the branch containing evaporator 80 and heat exchanger 30.

[0061] Referring to Figure 3, in some embodiments, the pump assembly 60 includes a first pump 61 and a second pump 62. The first pump 61 is configured to supply working fluid to the evaporator 80 and the preheater 70; the second pump 62 is connected in parallel with the first pump 61 and is also configured to supply working fluid to the evaporator 80 and the preheater 70. It should be understood that the first pump 61 and the second pump 62 are redundant backups of each other. When one of the circulation pumps fails to operate normally, the other circulation pump can support the continued operation of the power conversion equipment, reducing downtime for maintenance and ensuring the heat dissipation stability of the power conversion equipment.

[0062] Please see Figure 1 , Figure 2 and Figure 3 As shown, in some embodiments, the power conversion device further includes a control valve 90, which is located at the inlet end of the preheater 70 and configured to control the flow rate of the working fluid supplied to the preheater 70. It should be understood that when the heat exchanger 30 and the evaporator 80 share a pump, by setting the control valve 90 on the branch where the preheater 70 is located, the flow rate of the liquid working fluid supplied from the first pump 61 to the preheater 70 can be directly controlled by changing the valve opening, thereby controlling the flow rate of the preheating working fluid and adapting to fluctuations in preheating demand. When the preheater 70 malfunctions (e.g., heating element damage, pipeline blockage) or preheating is not required, if the ambient temperature inside the cavity 10 is high and the initial temperature of the working fluid is close to the phase change temperature, the control valve 90 can be completely closed, cutting off the working fluid supply to the preheater 70, achieving independent isolation of the preheater 70 branch, and improving the flexibility and maintainability of the power conversion device.

[0063] Please see Figure 4 As shown, in some embodiments, the pump assembly 60 includes a first pump 61 and a second pump 62. The first pump 61 is located between the liquid storage tank 50 and the preheater 70, and the second pump 62 is located between the liquid storage tank 50 and the evaporator 80. It should be understood that the first pump 61 is an independent power source for the branch containing the preheater 70. Its core function is to draw pure liquid working fluid from the liquid storage tank 50 after separation and condensation, pressurize it to form directional flow power, and specifically drive the working fluid to be transported along the pipeline to the preheater 70. The second pump 62 is an independent power source for the branch containing the evaporator 80. Its core function is to draw pure liquid working fluid from the liquid storage tank 50, pressurize it, and specifically transport it to the evaporator 80. By setting independent first pump 61 and second pump 62, on the one hand, the risk of unstable liquid supply caused by multiple branches sharing power can be reduced; on the other hand, when the flow demand of the preheater 70 is low, sufficient liquid supply to the evaporator 80 can be ensured. The flow control of the two branches is completely independent and does not interfere with each other, ensuring that the preheating accuracy and external heat dissipation efficiency can both reach the optimal state.

[0064] Please see Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, in some embodiments, the power conversion device further includes a first fan 100, which is disposed on one side of the condensation assembly 40. Please refer to... Figure 6 As shown, in some embodiments, the first fan 100 is disposed between the first condenser 41 and the second condenser 42. It should be understood that the core independent function of the first fan 100 is to enhance the heat exchange efficiency between the condensing assembly 40 and the external environment by actively driving airflow. When the first fan 100 is disposed on one side of the condensing assembly 40, it can provide directional airflow to the entire condensing assembly 40, achieving overall enhanced heat dissipation. When the first fan 100 is disposed between the first condenser 41 and the second condenser 42, it can simultaneously serve both condensers 41 and 42, achieving bidirectional precise airflow.

[0065] Please see Figure 7 and Figure 8 As shown, in some embodiments, the heat exchanger 30 includes a first manifold 31, a second manifold 32, and multiple branch pipes 33. The first manifold 31 is connected to the outlet end of the preheater 70; the second manifold 32 is connected to the inlet end of the condenser assembly 40; multiple branch pipes 33 are arranged in parallel between the first manifold 31 and the second manifold 32, and are respectively connected to the first manifold 31 and the second manifold 32. Multiple fins 34 are provided on the outer wall of the branch pipes 33, and the multiple fins 34 are spaced apart and arranged in an array. The power conversion device also includes a second fan 110, which is disposed in the cavity 10. It should be understood that the first manifold 31 serves as a transfer hub between the preheater 70 and the branch pipes 33, receiving the preheated working fluid output from the preheater 70 and distributing it evenly to the multiple parallel branch pipes 33. The function of the second manifold 32 is to collect the gas-liquid mixture of working fluid after heat absorption and phase change through multiple branch pipes 33, converging the dispersed branch working fluids into a main stream, and then uniformly transporting it to the condenser assembly 40. The parallel arrangement of multiple branch pipes 33 significantly increases the contact area between the heat exchanger 30 and the air inside the cavity 10, enhancing heat absorption capacity. Simultaneously, the parallel structure allows for flexible arrangement of the branch pipes 33, achieving close-range coverage of dispersed heat sources within the cavity, ensuring that the heat from each heat source is quickly absorbed by the working fluid carried by the nearest branch pipe 33. The fins 34 increase the effective heat transfer area of ​​the branch pipes 33, enabling the working fluid within the branch pipes 33 to absorb heat more efficiently. The spaced fins 34 allow for proper airflow, preventing airflow blockage caused by overly dense fins, further improving the heat transfer efficiency from the fins 34 to the air and accelerating the phase change of the working fluid. By installing a second fan 110 inside the cavity 10, the airflow inside the cavity 10 is increased, ensuring a uniform temperature at different locations inside the cavity 10, reducing the risk of local high temperatures, and improving the operational stability and safety of the heating device 20.

[0066] In the above embodiments, the descriptions of each embodiment have their own emphasis. Parts not described in detail in a particular embodiment can be referred to in the relevant descriptions of other embodiments. The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0067] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A power conversion device, characterized in that, include: A cavity (10) is configured to house a heating device (20); A heat exchanger (30) is disposed within the cavity (10), the heat exchanger (30) contains a working fluid, and the heat exchanger (30) is configured to conduct heat within the cavity (10); A condensing assembly (40) is disposed outside the cavity (10) and connected to the outlet end of the heat exchanger (30); A pump assembly (60) is connected to the outlet end of the condenser assembly (40); A preheater (70) is connected to the outlet end of the pump assembly (60) and the inlet end of the heat exchanger (30), and the preheater (70) is configured to preheat the working fluid.

2. The power conversion device according to claim 1, characterized in that, The power conversion device further includes: A liquid storage tank (50) is disposed outside the cavity (10) and is respectively connected to the outlet end of the condenser assembly (40) and the inlet end of the pump assembly (60).

3. The power conversion device according to claim 2, characterized in that, The power conversion device further includes: An evaporator (80) is connected in parallel with the heat exchanger (30) and the preheater (70). The evaporator (80) is disposed between the pump assembly (60) and the condenser assembly (40). The evaporator (80) is configured to conduct heat from the heating element (20) attached to the evaporator (80).

4. The power conversion device according to claim 3, characterized in that, The condensation assembly (40) includes: The first condenser (41) has its inlet end connected to the outlet end of the evaporator (80) and the outlet end of the heat exchanger (30), respectively. The first condenser (41) is located upstream of the liquid storage tank (50).

5. The power conversion device according to claim 3, characterized in that, The condensation assembly (40) includes: A first condenser (41) is disposed between the heat exchanger (30) and the liquid storage tank (50); The second condenser (42) is disposed between the evaporator (80) and the liquid storage tank (50).

6. The power conversion device according to any one of claims 3 to 5, characterized in that, The pump assembly (60) includes: A first pump (61) is configured to supply working fluid to the evaporator (80) and the preheater (70).

7. The power conversion device according to claim 6, characterized in that, The pump assembly (60) also includes: A second pump (62) is connected in parallel with the first pump (61) and is configured to supply working fluid to the evaporator (80) and the preheater (70).

8. The power conversion device according to claim 6, characterized in that, The power conversion device further includes: A control valve (90) is disposed at the inlet end of the preheater (70) and is configured to control the flow rate of the working fluid supplied to the preheater (70).

9. The power conversion device according to any one of claims 3 to 5, characterized in that, The pump assembly (60) includes: A first pump (61) is disposed between the liquid storage tank (50) and the preheater (70); A second pump (62) is disposed between the liquid storage tank (50) and the evaporator (80).

10. The power conversion device according to claim 5, characterized in that, The power conversion device further includes a first fan (100), which is disposed on one side of the condensation assembly (40); Alternatively, the first fan (100) may be positioned between the first condenser (41) and the second condenser (42).

11. The power conversion device according to claim 1, characterized in that, The heat exchanger (30) includes: The first manifold (31) is connected to the outlet end of the preheater (70); The second manifold (32) is connected to the inlet end of the condenser assembly (40); Multiple branch pipes (33) are arranged in parallel between the first manifold (31) and the second manifold (32), and are respectively connected to the first manifold (31) and the second manifold (32). Multiple fins (34) are provided on the outer wall of each branch pipe (33). The multiple fins (34) are spaced apart and arranged in an array. The power conversion device further includes a second fan (110), which is disposed inside the cavity (10).

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