Cooling device for power module

Abstract

A cooling device for a power module includes a collector cover including an interior space in which the power module is mounted, an inlet providing a passage for cooling fluid to flow into the interior space, and an outlet providing a passage for cooling fluid to discharge from the interior space, and a valve member disposed on the collector cover. The valve member includes a bimetal switch disposed on the collector cover so as to adjust the flow rate of the cooling fluid depending on the temperature.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit of priority to Korean Patent Application No. 10-2024-0122779, filed on September 10, 2024, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to a cooling device for a power module, which uses a cooling fluid to cool the power module. Background Technology

[0004] The power conversion unit in an environmentally friendly vehicle receives DC current from a high-voltage battery, converts it to AC current, and supplies the AC current to the electric motor. The motor's torque and revolutions per minute (RPM) are controlled by adjusting the magnitude and phase of the AC current. The power module of the power conversion unit is the conversion element that converts the DC current received from the high-voltage battery to AC current. If heat is generated during the conversion process and the temperature rises above a certain level, damage may occur. Therefore, all power modules in power conversion units require cooling. Improved cooling performance allows for the conversion of higher current ratings within the power module, thus enhancing the overall performance of the power conversion unit.

[0005] Power modules are used in environmentally friendly vehicles to control high voltage and high current. Therefore, they generate a great deal of heat, requiring proper cooling to maintain performance and durability. This can be achieved by using cooling fluids to cool the power modules, or by using the waste heat from the power modules to heat the vehicle. Summary of the Invention

[0006] Cooling devices used in power modules may be subjected to thermal shocks (e.g., pumpingout) caused by temperature changes, and thermal shocks may affect the durability of cooling devices used in power modules.

[0007] One aspect of the present invention is to provide a cooling device for a power module that can reduce factors that reduce durability due to temperature variations (e.g., the joint durability between the power module and its adjacent structures).

[0008] According to one aspect of the invention, a cooling device for a power module includes a manifold and a valve member. The manifold includes an internal space in which the power module is installed, an inlet providing a channel for cooling fluid to flow into the internal space, and an outlet providing a channel for cooling fluid to drain from the internal space. The valve member includes a bimetallic switch arranged in the manifold to regulate the flow rate of the cooling fluid according to temperature.

[0009] For example, the valve component can be configured such that the flow rate of the cooling fluid is higher when the temperature is above the reference temperature than when the temperature is below the reference temperature.

[0010] For example, the valve component can be configured to be more flexible when the temperature is below a reference temperature than when the temperature is above the reference temperature.

[0011] For example, the inlet may extend in a direction perpendicular to the direction in which the cooling fluid flows in the interior space of the manifold, and the valve member may be configured to block the space between the interior space of the manifold and the inlet when the valve member is bent.

[0012] For example, the inlet, the valve member, and the outlet may overlap each other in the direction of the inlet's extension, and the overlap area of ​​the valve member relative to the inlet may be configured to decrease as the valve member bends.

[0013] For example, the cooling device may further include a finned plate constructed in a manifold to contact the power module and having a plurality of cooling fins formed on the surface of the finned plate facing the inner surface of the manifold.

[0014] For example, the finned plate may include a mounting portion disposed on a surface facing the inner surface of the manifold in a region different from the region where the multiple cooling fins are formed, and the valve member may be arranged in the mounting portion.

[0015] For example, the cooling device may further include a guide wall configured to form a plurality of channels extending parallel to the flow direction of the cooling fluid flowing on the inner surface of the manifold.

[0016] For example, the valve component can be configured to block multiple channels when the temperature is above a reference temperature, and to open multiple channels when the temperature is below a reference temperature.

[0017] For example, each of the plurality of cooling fins may extend in a direction perpendicular to the flow direction of the cooling fluid.

[0018] For example, the finned plate may include a first finned plate disposed on one surface of the power module and having a first flow hole, and a second finned plate disposed on another surface of the power module and having a second flow hole, wherein the first flow hole and the second flow hole overlap each other.

[0019] For example, the power module may be a plurality of power modules arranged in the flow direction of the cooling fluid.

[0020] For example, the current collector cover may include a first current collector cover arranged on a plurality of cooling fins of a first finned plate and a second current collector cover arranged on a plurality of cooling fins of a second finned plate, wherein the first current collector cover and the second current collector cover are connected to each other. Attached Figure Description

[0021] The described and other aspects, features, and advantages of the invention will become clearer from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0022] Figure 1 This is a schematic diagram illustrating a cooling device for a power module according to an embodiment of the present invention;

[0023] Figure 2A This is an assembly diagram of a cooling device for a power module according to an embodiment of the present invention at high temperatures;

[0024] Figure 2B This is an assembly diagram of a cooling device for a power module at low temperatures according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram showing the cooling fins of a finned plate of a cooling device for a power module according to an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram illustrating the connection structure of the guide wall and finned plate of a cooling device for a power module according to an embodiment of the present invention; and

[0027] Figure 5 This is an assembly diagram showing the structure of a manifold cover for a cooling device for a power module, where the joint is further added according to an embodiment of the invention. Detailed Implementation

[0028] While the invention may be modified in various ways and taken in various alternative forms, its specific embodiments are shown in the accompanying drawings and described in detail below. However, it should be understood that the invention is not intended to be limited to the specific forms disclosed, but rather, the invention covers all modifications, equivalents, and alternatives that fall within the spirit and scope of the invention.

[0029] It will be understood that although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and a second element may similarly be referred to as a first element, without departing from the scope of the invention. As used herein, the term “and / or” includes any and all combinations of one or more of the associated enumerations.

[0030] The terminology used herein to describe embodiments of the invention is not intended to limit the scope of the invention. The articles “a” and “an” are singular because they have a single indicator; however, the use of the singular form herein should not preclude the presence of more than one indicator. In other words, unless the context clearly indicates otherwise, elements of the invention referred to in the singular form may be counted as one or more. It will be further understood that the terms “comprising,” “including,” “containing,” and / or “comprising” as used herein specify the presence of stated features, values, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, values, steps, operations, elements, components, and / or groups thereof.

[0031] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as understood by one of ordinary skill in the art to which this invention pertains. These terms, as defined in commonly used dictionaries, should be interpreted as having the same meaning as in the context of the relevant art, and should not be construed as having an ideal or overly formal meaning unless clearly defined in this application.

[0032] In this specification, a vehicle (including electric vehicles) means any vehicle that moves a transported object, such as a person, animal, or cargo, from a starting point to a destination. These vehicles are not limited to those that travel on roads or tracks.

[0033] In the following description, embodiments of the present invention will be described with reference to the accompanying drawings.

[0034] Reference Figure 1 , Figure 2A and Figure 2B According to an embodiment of the present invention, a cooling device for a power module may include a power module 10, a manifold cover 20, and valve components 50a and 50b.

[0035] Cooling devices for power modules can be installed in environmentally friendly vehicles. For example, environmentally friendly vehicles may include hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (HEVs), electric vehicles (EVs), fuel cell electric vehicles (FCEVs), etc., and may include high-voltage batteries and electric motors.

[0036] Power module 10 can convert DC current received from an external high-voltage battery (e.g., in an environmentally friendly vehicle) into AC current and output it to an external electric motor (e.g., in an environmentally friendly vehicle). Power module 10 may include an inverter for converting DC current into AC current, and the inverter may include multiple conversion elements. For example, power module 10 may receive DC current through multiple (e.g., four) input terminals on one side and output AC current through multiple (e.g., 20) output terminals on the other side. For example, each of the multiple conversion elements may include power semiconductor devices (e.g., insulated-gate bipolar transistors (IGBTs), thyristors, etc.) and / or diodes. Depending on the design, power module 10 may further include a converter or rectifier that converts AC current based on regenerative braking in the electric motor into DC current.

[0037] Power modules 10 can be multiple power modules 10 arranged in the flow direction of the cooling fluid (e.g., horizontal direction). As the number of power modules 10 increases, the total power capacity of the power modules 10 can increase. As the total power capacity of the power modules 10 increases, the magnitude of the current flowing to the input and output terminals of the power modules 10 can increase, the torque of the motor can become stronger, and the heat generated by the power modules 10 can also increase.

[0038] The manifold 20 may have an internal space, an inlet 21, and an outlet 22. The power modules 10 are installed in the internal space. The inlet 21 provides a passage for cooling fluid to flow into the internal space, and the outlet 22 provides a passage for cooling fluid to exit from the internal space. As cooling fluid flows from the inlet 21 to the outlet 22 once, all the power modules 10 installed in the manifold 20 can be cooled once.

[0039] The internal space of the manifold 20 can expand or contract according to temperature, and the stress caused by the expansion and contraction of the internal space of the manifold 20 can increase with the expansion of the temperature range. Stress may be a factor that reduces the durability of the internal space of the manifold 20 (e.g., the joint durability of adjacent structures of the power module 10).

[0040] When the temperature variation range of the internal space of the manifold 20 narrows, the stress caused by the temperature variation of the internal space of the manifold 20 can be reduced, and the durability of the internal space of the manifold 20 can be improved. For example, the temperature variation range may be affected by the external environment (e.g., external weather, season, and the region where the vehicle is located) and may also be affected by the temperature of the cooling fluid. Since the temperature of the cooling fluid may also be affected by the external environment, the temperature variation pattern of the internal space of the manifold 20 may be similar to the temperature variation pattern of the cooling fluid. For example, when the temperature of the internal space of the manifold 20 is high, the temperature of the cooling fluid can be high, and when the temperature of the internal space of the manifold 20 is low, the temperature of the cooling fluid can be low.

[0041] Therefore, when the flow rate of the cooling fluid varies according to the temperature of the manifold 20, the heat cooled by the cooling fluid in the internal space of the manifold 20 can vary according to the temperature, and the range of temperature variation of the external environment that depends on the internal space of the manifold 20 can be reduced.

[0042] Valve components 50a and 50b may include a bimetallic switch arranged in the manifold 20, such that the flow rate of the cooling fluid is regulated according to temperature. The bimetallic switch may have a shape in which two metal plates with different coefficients of thermal expansion overlap each other, and the angle of bending of the bimetallic switch may vary according to temperature. Therefore, the cooling device for the power module according to an embodiment of the invention can reduce the range of temperature variations depending on the external environment and the internal space of the manifold 20, and can reduce factors that reduce durability (e.g., the joint durability of adjacent structures of the power module 10) depending on temperature variations.

[0043] Furthermore, the bimetallic switches of valve components 50a and 50b can operate (e.g., bend) without external control signals (e.g., signals from the electronic control unit in an environmentally friendly vehicle) and without external power supply (e.g., power from the battery in an environmentally friendly vehicle). That is, even without a separate structure for controlling valve components 50a and 50b (and / or supplying power to them), the cooling device for the power module according to an embodiment of the invention can control the flow rate of the cooling fluid based on temperature, thus reducing the cost associated with a separate structure. For example, the bimetallic switches can be manufactured according to a molding die.

[0044] Reference Figure 2AWhen the temperature of the internal space of the manifold 20 and the cooling fluid (e.g., 65 degrees Celsius) is higher than the reference temperature (e.g., room temperature, 25 degrees Celsius), the valve member 50a can open the space between the internal space of the manifold 20 and the inlet 21, thereby maximizing the flow rate of the cooling fluid. Therefore, the amount of heat cooled by the cooling fluid in the internal space of the manifold 20 can be relatively large.

[0045] Reference Figure 2B When the temperature of the internal space of the manifold 20 and the cooling fluid (e.g., -40°C to 0°C) is lower than the reference temperature (e.g., room temperature, 25°C), the valve member 50b can block at least a portion of the space between the internal space of the manifold 20 and the inlet 21, thereby reducing the flow rate of the cooling fluid. Therefore, the heat cooled by the cooling fluid in the internal space of the manifold 20 can be relatively small or nonexistent.

[0046] In other words, valve components 50a and 50b can be configured such that the flow rate of the cooling fluid when the temperature of the internal space of the manifold 20 and the cooling fluid is higher than that when its temperature is lower than the reference temperature is higher than that when the temperature is lower than the reference temperature. Therefore, the temperature variation range of the internal space of the manifold 20, which depends on the external environment (e.g., external weather, season, and the region of environmentally friendly vehicles), can be narrowed.

[0047] For example, valve members 50a and 50b can be configured to be more flexed when the temperature of the internal space of the manifold 20 and the cooling fluid is below a reference temperature (e.g., room temperature, 25 degrees Celsius) than when it is above a reference temperature. Valve members 50a and 50b can operate (e.g., bend) without external control signals (e.g., signals from the electronic control unit in an environmentally friendly vehicle) and without external power supply (e.g., power supply from the battery in an environmentally friendly vehicle). That is, even without a separate structure controlling the bending (and / or supplying power to) of valve members 50a and 50b, the cooling device for the power module according to an embodiment of the invention can control the flow rate of the cooling fluid based on temperature, thus reducing the cost associated with a separate structure.

[0048] For example, inlet 21 may extend in a direction perpendicular to the flow direction of the cooling fluid within the interior space of manifold 20 (e.g., vertical), and inlet 21, valve members 50a and 50b, and outlet 22 may overlap each other in the extension direction of inlet 21 (e.g., vertical). Valve members 50a and 50b may be configured to block the space between the interior space of manifold 20 and inlet 21 when valve members 50a and 50b bend, and the overlap area of ​​valve members 50a and 50b relative to inlet 21 may be configured to decrease as valve members 50a and 50b bend. As the overlap area decreases, valve members 50a and 50b can more significantly reduce the flow rate of the cooling fluid. Inlet 21 and outlet 22 may be configured in series, and although the schematic diagram shows the cooling fluid flowing in the vertical direction, the flow direction may be opposite and is not limited to the vertical direction.

[0049] Reference Figure 2A , Figure 2B and Figure 3 According to an embodiment of the invention, the cooling device for the power module may further include a fin plate 30, which is constructed in the manifold 20, contacts the power module 10, and has a plurality of cooling fins 31 formed on the surface of the fin plate 30 facing the inner surface of the manifold 20.

[0050] Since the finned plate 30 is in contact with the power module 10, it can absorb the heat generated by the power module 10. Because multiple cooling fins 31 increase the contact area between the finned plate 30 and the cooling fluid, the cooling efficiency of the cooling fluid can be improved. The cooling device for the power module according to an embodiment of the present invention can reduce factors that reduce the bonding durability between the finned plates 30 of the power module 10 due to significant temperature variations within the internal space of the manifold 20.

[0051] For example, the finned plate 30 may include a first finned plate 30a disposed on one surface (e.g., the upper surface) of the power module 10 and having a first flow hole 32a, and a second finned plate 30b disposed on another surface (e.g., the lower surface) of the power module 10 and having a second flow hole 32b. Thus, the power module 10 can generate heat through both surfaces. The first finned plate 30a and the second finned plate 30b may have the same shape and may be arranged symmetrically relative to each other, but are not limited thereto.

[0052] The manifold 20 may include a first manifold 20a arranged on a plurality of cooling fins 31 of the first finned plate 30a and a second manifold 20b arranged on a plurality of cooling fins (not shown) of the second finned plate 30b. The first manifold 20a and the second manifold 20b may have the same shape and may be arranged symmetrically relative to each other, but are not limited thereto.

[0053] A first finned plate 30a can be arranged between the first current collector cover 20a of the current collector cover 20 and the power module 10, and a second finned plate 30b can be arranged between the second current collector cover 20b of the current collector cover 20 and the power module 10. When the first current collector cover 20a and the second current collector cover 20b are combined, the first finned plate 30a and the second finned plate 30b can be tightly attached to both sides of the power module 10. For example, the edge of the first current collector cover 20a can be combined with the first finned plate 30a by at least one of welding, bonding, and bolting, and the edge of the second current collector cover 20b can be combined with the second finned plate 30b by at least one of welding, bonding, and bolting.

[0054] The first flow hole 32a and the second flow hole 32b can overlap each other in the vertical direction, and the cooling fluid can pass through the first flow hole 32a and the second flow hole 32b. Therefore, when the cooling fluid flows from the inlet 21 to the outlet 22 once, each side of the power module 10 can be cooled once.

[0055] The finned plate 30 may include a mounting portion disposed in a region (e.g., an end region) different from the region (e.g., a central region) on the surface where the plurality of cooling fins 31 are formed facing the inner surface of the manifold 20, and valve members 50a and 50b may be arranged in the mounting portion. For example, the mounting portion may be formed recessed or recessed in a shape substantially the same as that of the valve members 50a and 50b, and may fix the position of the valve members 50a and 50b.

[0056] Alternatively, the mounting portions located in different areas (e.g., the two end areas) of the finned plate 30 can be bonded to a portion of the valve components 50a and 50b by adhesive members, or by mechanical connections (e.g., bolt connections, screw connections, double-ended bolt connections, etc.) to a portion of the valve components 50a and 50b.

[0057] Reference Figure 2A , Figure 2B and Figure 4 The cooling device for a power module according to an embodiment of the invention may further include a guide wall 40 configured to form a plurality of channels extending parallel to each other in the flow direction (e.g., horizontal) of the cooling fluid flowing from the inner surface of the manifold 20. The cooling fluid can pass through the plurality of channels. By design, the plurality of channels may be zig-connected to each other, and the cooling fluid may further circulate through the plurality of channels as if in turbulent flow.

[0058] Valve components 50a and 50b can be configured to block multiple channels when the internal space of the manifold 20 and the temperature of the cooling fluid are above a reference temperature (e.g., room temperature, 25 degrees Celsius), and to open multiple channels when they are below the reference temperature. Since the multiple channels of the guide wall 40 are part of the internal space of the manifold 20, the cooling performance of the cooling fluid can be adjusted when the valve components 50a and 50b block the multiple channels of the guide wall 40.

[0059] For example, the guide wall 40 can be formed to contact the cooling fins 31 of the finned plate 30, and the main flow of cooling fluid can be formed through the cooling fins 31. The guide wall 40 can be arranged on the first manifold 20a and can contact the cooling fins 31 of the first finned plate 30a, and can be arranged on the second manifold 20b and can contact the cooling fins (not shown) of the second finned plate 30b. The guide wall (not shown) arranged on the first manifold 20a and the guide wall 40 arranged on the second manifold 20b can be arranged to be point-symmetrical with respect to each other in the vertical direction, but is not limited thereto.

[0060] Reference Figure 3 and Figure 4 Each of the plurality of cooling fins 31 can extend in a direction perpendicular to the flow direction of the cooling fluid. Therefore, as the cooling fluid flows through the plurality of channels of the guide wall 40, it can be cooled on the plurality of cooling fins 31 by means of jet impingement. Jet impingement can achieve a locally high heat transfer effect at each point of the finned plate 30. The plurality of cooling fins 31 are not limited to the structure used for jet impingement and can have needle-fin or wave-fin structures depending on the design.

[0061] Reference Figure 5 The first manifold cover 20a may include a connecting portion 60, which may include a first connecting portion 63. The second manifold cover 20b may include a second connecting portion 23. By connecting the first connecting portion 63 and the second connecting portion 23 to each other, the connecting portion 60 can compress the first manifold cover 20a, and the first manifold cover 20a and the second manifold cover 20b can be more securely connected to each other. For example, the first connecting portion 63 and the second connecting portion 23 can be connected by a mechanical connection (e.g., bolt connection, screw connection, double-ended bolt connection, etc.), but are not limited thereto.

[0062] For example, the connecting part 60 can be connected to the first manifold cover 20a through the inlet 21 and through the through hole 61. The first connecting part 63 can be a plurality of first connecting parts 63 arranged at equal intervals along the edge of the connecting part 60, and the second connecting part 23 can be a plurality of second connecting parts 23 arranged at equal intervals along the edge of the second manifold cover 20b.

[0063] At the same time, with Figure 2A Unlike the cooling device used for power modules, valve member 50a can selectively block the space between the internal space of the second manifold 20b and the outlet 22 according to temperature. The position of valve member 50a is not limited to inlet 21 or outlet 22, and can be arranged at any position in the cooling device for power modules where the flow rate of cooling fluid can be adjusted according to temperature.

[0064] The cooling device for power modules according to embodiments of the present invention can reduce factors that reduce durability due to temperature variations (e.g., the joint durability between the power module and adjacent structures), and can reduce the cost associated with individual structures because the flow rate of the cooling fluid can be adjusted according to temperature even without a control valve component (and / or power supplied to it).

[0065] Although the embodiments have been described and illustrated above, it will be apparent to those skilled in the art that modifications and alterations may be made without departing from the scope of the invention as defined by the appended claims.

Claims

1. A cooling device for a power module, the cooling device comprising: A manifold includes an internal space, an inlet, and an outlet. The internal space has a power module, the inlet provides a channel for cooling fluid to flow into the internal space, and the outlet provides a channel for cooling fluid to exit from the internal space. as well as A valve component comprising a bimetallic switch disposed on the manifold, the bimetallic switch being configured to regulate the flow rate of cooling fluid according to temperature.

2. The cooling device for a power module according to claim 1, wherein, The valve component is configured such that the flow rate of the cooling fluid is higher when the temperature is above the reference temperature than when the temperature is below the reference temperature.

3. The cooling device for a power module according to claim 2, wherein, The valve component is configured to be more flexible when the temperature is below the reference temperature than when the temperature is above the reference temperature.

4. The cooling device for a power module according to claim 3, wherein: The inlet extends in a direction perpendicular to the direction in which the cooling fluid flows within the interior space of the manifold; The valve member is configured to block the space between the internal space of the manifold and the inlet when the valve member is bent.

5. The cooling device for a power module according to claim 4, wherein, The inlet, the valve member, and the outlet overlap each other in the direction of extension of the inlet, and the overlap area of ​​the valve member relative to the inlet is configured to decrease as the valve member bends.

6. The cooling device for a power module according to claim 1, further comprising a finned plate constructed in a manifold, configured to contact the power module, and having a plurality of cooling fins formed on a surface of the finned plate facing the inner surface of the manifold.

7. The cooling device for a power module according to claim 6, wherein, The finned plate includes a mounting portion disposed on a surface facing the inner surface of the manifold in a region different from the region where multiple cooling fins are formed, and the valve member is arranged in the mounting portion.

8. The cooling device for a power module according to claim 6, further comprising a guide wall forming a plurality of channels extending parallel to the flow direction of the cooling fluid flowing on the inner surface of the manifold.

9. The cooling device for a power module according to claim 8, wherein, The valve component is configured to block the plurality of channels when the temperature is higher than the reference temperature, and to open the plurality of channels when the temperature is lower than the reference temperature.

10. The cooling device for a power module according to claim 9, wherein, Each of the plurality of cooling fins extends in a direction perpendicular to the flow direction of the cooling fluid.

11. The cooling device for a power module according to claim 6, wherein, The finned plate includes: A first finned plate, disposed on a surface of the power module and having a first flow hole; and A second finned plate is arranged on the other surface of the power module and has a second flow hole; The first flow hole and the second flow hole overlap each other.

12. The cooling device for a power module according to claim 11, wherein, The power module includes multiple power modules arranged in the flow direction of the cooling fluid.

13. The cooling device for a power module according to claim 11, wherein, The manifold includes: The first manifold cover is arranged on multiple cooling fins of the first finned plate; and The second manifold cover is arranged on multiple cooling fins of the second fin plate; The first and second collection covers are connected to each other.

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