COOLER FOR POWER MODULE OF AN INVERTER

Description

BACKGROUND1. Field

[0001] The following disclosure relates to a cooler for a power module of an inverter, and more particularly, to a cooler for a power module of an inverter, which is configured to effectively cool a power module coupled to a heat sink.2. Discussion of Related Art

[0002] In general, a vehicle is equipped with an inverter system as a power conversion device for converting high-voltage direct-current (DC) power generated from a battery or a fuel cell into alternating-current (AC) power of three phases (U-, V-, and W-phases).

[0003] Such an inverter system includes a power module, including a power conversion switching element (an insulated gate bipolar transistor (IGBT)), and a gate driving circuit.

[0004] When the inverter system operates, a large amount of heat is generated from a chip installed in a power module and emitting heat (hereinafter referred to as a chip) and thus a cooling structure such as a heat sink may be used to dissipate heat generated from the chip of the power module or the like.

[0005] For example, an existing power module cooling structure may employ a structure in which a pin is disposed on a base plate of a power module and the power module is watertight-treated and immersed in a housing with a flow path.

[0006] Specifically, either a serial cooling structure for cooling power modules corresponding to the U-, V-, and W-phases of an inverter by causing a fluid, such as cooling water flowing in a flow path (hereinafter referred to as a fluid), to flow through the power modules in series or a parallel cooling structure for cooling power modules corresponding to U-, V-, and W-phases of an inverter by causing a fluid to flow through the power modules in parallel is employed.

[0007] However, the serial cooling structure is configured to sequentially cool the power modules corresponding to the U-, V-, and W-phases of the inverter using a fluid and thus the power module at a rear end is less effectively cooled than the power module at a front end, thus increasing a temperature deviation between the power modules.

[0008] Meanwhile, the parallel cooling structure prevents an increase in a temperature deviation between the power modules but is configured to distribute a fluid to cause a relatively small amount of the fluid to flow through each of the power modules, thus reducing the cooling efficiency of each of the power modules.

[0009] US 2006 / 108098 A1 discloses an apparatus for cooling at least one heated surface includes a base plate defining a number of inlet and outlet manifolds. The apparatus also includes at least one substrate having inner and outer surfaces. The inner surface is coupled to the base plate and defines a number of microchannels that receive the coolant from the inlet manifolds and deliver the coolant to the outlet manifolds.

[0010] US 2010 / 226093 A1 discloses a substrate for power electronics mounted thereon, comprising a middle ceramic layer having a lower surface and an upper surface, an upper metal layer attached to the upper surface of the middle ceramic layer, and a lower metal layer attached to the lower surface of the middle ceramic layer. The lower metal layer has a plurality of millichannels configured to deliver a coolant for cooling the power electronics, and the millichannels are formed on the lower metal layer prior to attachment to the lower surface of the middle ceramic layer.

[0011] Therefore, it is necessary to develop a cooler, for a power module of an inverter, to prevent an increase in a temperature deviation between a plurality of power modules and increase the cooling efficiency of each of the power modules.SUMMARY

[0012] A cooler according to the present invention is set forth in claim 1. Preferred embodiments are provided in the dependent claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is an exploded perspective view of a cooler for a power module of an inverter according to an embodiment. FIG. 2 is a plan view of a power module. FIG. 3 is a plan view of one surface of a heat sink to which a power module is coupled; FIG. 4 is a bottom view of another surface of the heat sink in which a microfluidic channel is installed. FIG. 5 is an enlarged view of a region A of FIG. 4. FIG. 6 is a cross-sectional view of a cooler for a power module of an inverter, taken in a direction perpendicular to a second direction. FIG. 7 is a diagram illustrating a state in which a fluid flows in a cooler for a power module of an inverter.

[0014] Throughout the drawings and the detailed description, unless otherwise described or provided, the same drawing reference numerals will be understood to refer to the same elements, features, and structures. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience.DETAILED DESCRIPTION OF EMBODIMENTS

[0015] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings and the following description. Throughout the specification, the same reference numbers represent the same elements.

[0016] Hereinafter, a configuration of a cooler for a power module of an inverter according to an embodiment of the present invention will be described.

[0017] FIG. 1 is an exploded perspective view of a cooler for a power module of an inverter according to an embodiment.

[0018] Referring to FIG. 1, a cooler 1 for a power module of an inverter includes a plurality of power modules 100, a heat sink 200, and a housing 300.

[0019] First, the power module 100 will be described.

[0020] The power module 100 is commonly referred to as a power semiconductor module, and may include an insulated gate bipolar transistor (IGBT), a MOSFET or bipolar transistor, or the like and be formed by disposing a direct-bonded copper (DBC) substrate on an upper surface of a base plate and attaching a chip to the DBC substrate.

[0021] The plurality of power modules 100 may be included in the cooler 1 for a power module of an inverter. For example, the plurality of power modules 100 may be configured as three power modules 100 corresponding to the U-phase, V-phase, and W-phase of an inverter.

[0022] FIG. 2 is a plan view of a power module.

[0023] Referring to FIG. 2, a power module 100 may include a plurality of chips 110 arranged in parallel in a row direction and a column direction perpendicular to the row direction.

[0024] As described above, when an inverter system operates, high heat is generated from the chips 110 and the power module 100 may be effectively cooled by dissipating the heat generated from the chips 110.

[0025] Next, the heat sink 200 will be described.

[0026] The heat sink 200 is a thermally conductive thin plate to which the power module 100 from which heat is to be dissipated may be coupled, and extends in a first direction.

[0027] FIG. 3 is a plan view of one surface of a heat sink to which a power module is coupled.

[0028] As shown in FIG. 3, a plurality of power modules 100 are coupled to one surface of a heat sink 200 such that a row direction is parallel to a first direction.

[0029] FIG. 4 is a bottom view of another surface of the heat sink in which a microfluidic channel is installed. FIG. 5 is an enlarged view of a region A of FIG. 4.

[0030] As shown in FIG. 4, a microfluidic channel 210 is installed on another surface of the heat sink 200.

[0031] The microfluidic channel 210 may employ a configuration of a conventional microfluidic channel through which a fluid may flow. As shown in FIG. 5, a plurality of fine grooves 211 extending in a longitudinal direction may be formed.

[0032] In this case, the microfluidic channel 210 may be formed such that the longitudinal direction in which the fine grooves 211 are formed is parallel to the column direction in which the plurality of chips 110 are arranged.

[0033] The microfluidic channel 210 covers a separation part 330, which will be described below, to form a fine flow path 360. At least one chip 110 among the plurality of chips 110 may be positioned in a vertical direction perpendicular to the row direction and the column direction from the fine flow path 360.

[0034] That is, the microfluidic channel 210 may be installed on the heat sink 200 such that the fine flow path 360 passes through a lower portion of the chips 110 included in the power module 100.

[0035] Next, the housing 300 will be described.

[0036] The housing 300 may have a structure in which a fluid may flow therein, and includes a first groove part 310, a second groove part 320, and the separation part 330 as shown in FIG. 1.

[0037] The first groove part 310 includes an inlet 311 into which a fluid is introducible and a first groove 312 extending in a second direction to communicate with the inlet 311, and the second groove part 320 includes an outlet 321 through which the fluid is dischargeable and a second groove 322 extending in the second direction to communicate with the outlet 321.

[0038] FIG. 6 is a cross-sectional view of a cooler for a power module of an inverter, taken in a direction perpendicular to a second direction.

[0039] As shown in FIG. 6, when the heat sink 200 is coupled to the housing 300 such that the first direction is parallel to the second direction, the heat sink 200 is covered with the first groove part 310 to form a first flow path 340 and the heat sink 200 is covered with the second groove part 320 to form a second flow path 350.

[0040] Here, a cross-sectional area of the second flow path 350 perpendicular to the second direction is formed to be larger than that of the first flow path 340 perpendicular to the second direction to reduce a pressure loss of the fluid flowing in the cooler 1 for a power module of an inverter.

[0041] The separation part 330 is formed between the first groove part 310 and the second groove part 320 to separate the first groove part 310 and the second groove part 320. As described above, when the heat sink 200 is coupled to the housing 300, the microfluidic channel 210 covers the separation part 330 to form the fine flow path 360.

[0042] Here, a cross-sectional area of the fine flow path 360 perpendicular to the longitudinal direction is formed to be smaller than that of the first flow path 340 perpendicular to the second direction, so that the fluid may flow quickly in the fine flow path 360 to effectively cool the plurality of power modules 100.

[0043] Specifically, the cross-sectional area of the fine flow path 360 perpendicular to the longitudinal direction may be set to be 0.1 times or more and 0.7 times or less of that of the first flow path 340 perpendicular to the second direction. In this case, the plurality of power modules 100 may be effectively cooled by the fluid flowing in the fine flow path 360.

[0044] A chamfer may be formed at a corner C of the separation part 330 adjacent to the first groove part 310, and when the chamfer is formed on the separation part 330, the fluid may more easily flow through the first flow path 340, the fine flow path 360, and the second flow path 350, thereby reducing a pressure loss of the fluid flowing in the cooler 1 for a power module of an inverter.

[0045] Meanwhile, when the heat sink 200 covers the first groove part 310, a vertical height of the first flow path 340 in a direction from the first flow path 340 to the second flow path 350 may gradually increase.

[0046] In addition, when the heat sink 200 covers the second groove part 320, a vertical height of the second flow path 350 in the direction from the first flow path 340 to the second flow path 350 may gradually decrease.

[0047] That is, as shown in FIG. 6, when the heat sink 200 is coupled to the housing 300, an inclined corner portion B may be provided on the first flow path 340 and the second flow path 350.

[0048] As described above, when the inclined corner portion B is provided on the first flow path 340 and the second flow path 350, the fluid may more easily flow through the first flow path 340, the fine flow path 360, and the second flow path 350, thereby reducing a pressure loss of the fluid flowing in the cooler 1 for a power module of an inverter.

[0049] Hereinafter, operations and effects of a cooler for a power module of an inverter according to an embodiment will be described.

[0050] FIG. 7 is a diagram illustrating a state in which a fluid flows in a cooler for a power module of an inverter.

[0051] Referring to FIG. 7, when a fluid such as cooling water flows into the inlet 311 of the housing 300, the fluid flows in the first flow path 340 and thereafter flows into a plurality of fine flow paths 360, thus dissipating heat generated from the plurality of power modules 100.

[0052] In this case, the fine flow path 360 is formed to have a smaller cross-sectional area than that of the first flow path 340 and to pass through a lower portion of the chip 110 generating a large amount of heat. Therefore, the fluid flowing in the fine flow path 360 flows at a high speed to effectively cool the power module 200.

[0053] The fluid passing through the inside of the plurality of fine flow paths 360 flows into the second flow path 350 and thereafter is discharged to the outside of the cooler 1 for a power module of an inverter through the outlet 321 of the housing 300.

[0054] In the cooler 1 for a power module of an inverter, the second flow path 350 is formed to have a larger cross-sectional area than that of the first flow path 340, the inclined corner portion B is formed on the first flow path 340 and the second flow path 350, and a chamfer is formed on the corner C of the separation part 330 adjacent to the first groove part 310, thereby reducing a pressure loss of the fluid flowing in the cooler 1 for a power module of an inverter.

[0055] As described above, a cooler for a power module of an inverter according to an embodiment is configured to cause a fluid to flow through power modules of an inverter in parallel to cool the power modules, thereby preventing an increase in a temperature deviation between the plurality of power modules.

[0056] A fine flow path formed by a microfluidic channel is configured to be located in a lower portion of a chip that generates a large amount of heat and to have a relatively narrow cross-sectional area to allow the fluid to flow at a high speed, thereby achieving an effect of effectively cooling each of the power modules.

[0057] In addition, a cross-sectional area of a second flow path is set to be larger than that of a first flow path, an inclined corner portion is provided on the first flow path and the second flow path, and a chamfer is provided on a corner of a separation part to minimize a pressure loss of a fluid flowing to cool a plurality of power modules, thereby reducing load on a device such as a water pump for injecting the fluid.

[0058] According to an embodiment, a cooler for a power module of an inverter is configured to cause a fluid to flow through power modules of an inverter in parallel to cool the power modules of the inverter, thereby preventing an increase in a temperature deviation between the power modules.

[0059] A fine flow path formed by a microfluidic channel is configured to be located in a lower portion of a chip that generates a large amount of heat and to have a relatively narrow cross-sectional area to allow the fluid to flow at a high speed, thereby achieving an effect of effectively cooling each of the power modules.

[0060] In addition, a cross-sectional area of a second flow path is set to be larger than that of a first flow path, an inclined corner portion is provided on the first flow path and the second flow path, and a chamfer is provided on a corner of a separation part to minimize a pressure loss of a fluid flowing to cool a plurality of power modules, thereby reducing load on a device such as a water pump for injecting the fluid.

[0061] As disclosed above, there is provided a cooler for a power module of an inverter, which is capable of preventing an increase in a temperature deviation between a plurality of power modules.

[0062] As disclosed above, there is provided a cooler for a power module of an inverter, which is capable of effectively cooling each of a plurality of power modules when the plurality of power modules are cooled.

[0063] As disclosed above, there is provided a cooler for a power module of an inverter, which is capable of minimizing a pressure loss of a fluid flowing to cool a plurality of power modules.Reference Numerals

[0064] 1: cooler for power module of inverter 100: power module 110: chip 200: heat sink 210: microfluidic channel 211: fine groove 300: housing 310: first groove part 320: second groove part 330: separation part 340: first flow path 350: second flow part 360: fine flow path

Claims

1. A cooler (1) for a heat generating device, comprising: a heat sink (200) extending in a first direction, wherein one surface of the heat sink (200) is configured to be coupled to the heat generating device and a microfluidic channel (210) comprising grooves (211) is disposed on another surface of the heat sink (200), the grooves (211) extending in a longitudinal direction of the heat sink (200); and a housing (300) comprising a first groove part (310) comprising an inlet (311) configured to receive a fluid and a first groove (312) extending in a second direction to communicate with the inlet (311), a second groove part (320) comprising an outlet (321) configured to discharge the fluid and a second groove (322) extending in the second direction to communicate with the outlet (321), and a separation part (330) formed between the first groove part (310) and the second groove part (320), wherein the heat sink (200) is coupled to the housing (300) to cause the first direction to be parallel to the second direction, the first groove (312) is covered with the heat sink (200) to form a first flow path (340), the second groove part (320) is covered with the heat sink (200) to form a second flow path (350), and the microfluidic channel (210) covers the separation part (330) to cause the grooves (211) to form flow paths (360) for communication of the first flow path (340) and the second flow path (350), and wherein the flow paths (360) are configured to dispose at least one component of the heat generating device in a vertical direction perpendicular to a row direction and a column direction from the flow paths (360), wherein a cross-sectional area of the flow path (360) perpendicular to the longitudinal direction is less than a cross-sectional area of the first flow path (340) perpendicular to the second direction, characterised in that a cross-sectional area of the second flow path (350) perpendicular to the second direction is greater than the cross-sectional area of the first flow path (340) perpendicular to the second direction.

2. The cooler (1) according to claim 1, wherein the heat generating device includes an inverter, the inverter includes power modules (100) comprising chips (110) arranged in the row direction and the column direction perpendicular to the row direction, and wherein the first direction is parallel to the row direction, the power modules (100) being coupled to the one surface of the heat sink (200), the grooves (211) extending in a longitudinal direction of the heat sink (200).

3. The cooler (1) of claim 1 or 2, wherein the longitudinal direction is parallel to the column direction.

4. The cooler (1) of any of claims 1 to 3, wherein the cross-sectional area of the flow paths (360) perpendicular to the longitudinal direction is 0.1 times or more and 0.7 times or less of the cross-sectional area of the first flow path (340) perpendicular to the second direction.

5. The cooler (1) of any of claims 1 to 4, wherein a height of the first flow path (340) in the vertical direction increases in a direction from the first flow path (340) to the second flow path (350), when the heat sink (200) covers the first groove part (310), and a height of the second flow path (350) in the vertical direction decreases in the direction from the first flow path (340) to the second flow path (350), when the heat sink (200) covers the second first groove part (310).

6. The cooler (1) of any of claims 1 to 5, wherein a chamfer is provided on a corner of the separation part (330) adjacent to the first groove part (310).

7. The cooler (1) of claim 5 or 6, wherein the power modules (100) comprise three power modules corresponding to U-, V-, and W-phases of the inverter.