Power converter

Abstract

A power conversion device (1) comprises: a plurality of circuit components (21, 22, 23); a metal base substrate (30); a first heat transport member (40); and a cooler (50). The metal base substrate (30) includes: a main surface (33) on which the plurality of circuit components (21, 22, 23) are mounted; and an end surface (32) connected to the main surface (33). The first heat transport member (40) includes a main surface (43), and an end surface (42) facing the cooler (50). The end surface (32) and the end surface (42) are thermally connected to the cooler (50). The main surface (43) is thermally connected to the metal base substrate (30).

Description

[Technical Field]

[0001] The present disclosure relates to a power converter. [Background Art]

[0002] Japanese Patent No. 4983959 (Patent Document 1) discloses a switching power supply including an electronic component, a storage case that stores the electronic component, a pedestal portion integrally formed with the storage case and on which the electronic component is placed, and a refrigerant flow path that penetrates through the pedestal portion and through which a refrigerant for cooling the electronic component flows. [Prior Art Literature] [Patent Literature]

[0003] [Patent Document 1] Japanese Patent No. 4983959 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] An object of the present disclosure is to provide a power converter capable of cooling a plurality of circuit components without increasing the size of a cooler even when the number of circuit components increases. [Means for Solving the Problem]

[0005] A power converter according to a first aspect of the present disclosure includes a plurality of circuit components, a metal base substrate including a metal plate, a heat transport member, and a cooler. The metal base substrate includes a first main surface on which the plurality of circuit components are mounted, and a first end surface connected to the first main surface. The thermal conductivity of the heat transport member is equal to or higher than the thermal conductivity of the metal plate. The heat transport member includes a second main surface, and a second end surface connected to the second main surface and facing the cooler. The first end surface and the second end surface are thermally connected to the cooler. The second main surface is thermally connected to the metal base substrate.

[0006] A power converter in a second aspect of the present disclosure comprises a plurality of circuit components, a metal base substrate including a metal plate, a heat transport member, and a cooler. The metal base substrate includes a first main surface on which the plurality of circuit components are mounted, a second main surface opposite to the first main surface, and a first end surface connected to the first and second main surfaces. The metal plate includes the second main surface. The first end surface faces the cooler and is thermally connected to the cooler. The thermal conductivity of the heat transport member is greater than or equal to the thermal conductivity of the metal plate. The heat transport member faces the second main surface and is thermally connected to the second main surface. In a plan view of the first main surface, the heat transport member includes a projection protruding from the first end surface. The cooler is provided with holes or recesses. The projection of the heat transport member is inserted into the holes or recesses and is thermally connected to the cooler. [Effects of the Invention]

[0007] The cooler is thermally connected to the first end face of the metal base substrate and the heat transport member. Heat generated by multiple circuit components is transferred to the cooler by both the metal base substrate and the heat transport member and concentrated in the cooler. According to the power conversion device of this disclosure, even if the number of circuit components increases and the size of the metal base substrate increases, multiple circuit components can be cooled without increasing the size of the cooler. [Brief explanation of the drawing]

[0008] [Figure 1] This is a circuit diagram of a power conversion device according to Embodiment 1. [Figure 2] This is a schematic plan view of the power conversion device according to Embodiment 1. [Figure 3] This is a schematic cross-sectional view of the power conversion device according to Embodiment 1, taken along the cross-sectional line III-III shown in Figure 2. [Figure 4] This is a schematic, partially enlarged cross-sectional view of region IV shown in Figure 3 of the power conversion device according to Embodiment 1. [Figure 5] This is a schematic cross-sectional view of the power conversion device according to Embodiment 2. [Figure 6] This is a schematic cross-sectional view of a power conversion device according to Embodiment 3. [Figure 7] This is a schematic plan view of the power conversion device according to Embodiment 4. [Figure 8] This is a schematic cross-sectional view of the power conversion device according to Embodiment 4, taken along the cross-sectional line VIII-VIII shown in Figure 7. [Figure 9] This is a schematic cross-sectional view of the power conversion device according to Embodiment 4, taken along the cross-sectional line IX-IX shown in Figure 7. [Figure 10] This is a schematic plan view of the power conversion device according to Embodiment 5. [Figure 11] This is a schematic cross-sectional view of the power conversion device according to Embodiment 5, taken along the cross-sectional line XI-XI shown in Figure 10. [Figure 12] This is a schematic plan view of a power conversion device according to Embodiment 6. [Figure 13] This is a schematic cross-sectional view of the power conversion device according to Embodiment 6, taken along the cross-sectional line XIII-XIII shown in Figure 12. [Figure 14] This is a schematic cross-sectional view of the power conversion device according to Embodiment 6, taken along the cross-sectional line XIV-XIV shown in Figure 12. [Figure 15] This is a schematic cross-sectional view of the power conversion device according to Embodiment 6, taken along the cross-sectional line XV-XV shown in Figure 12. [Figure 16] This is a schematic plan view of the power conversion device according to Embodiment 7. [Figure 17] This is a schematic cross-sectional view of the power conversion device according to Embodiment 7, taken along the cross-sectional line XVII-XVII shown in Figure 16. [Figure 18] This is a schematic cross-sectional view of the power conversion device according to Embodiment 7, taken along the cross-sectional line XVIII-XVIII shown in Figure 16. [Figure 19] This is a schematic cross-sectional view of the power conversion device according to Embodiment 7, taken along the cross-sectional line XIX-XIX shown in Figure 16. [Figure 20] This is a schematic plan view of the power conversion device according to Embodiment 8. [Figure 21] This is a schematic cross-sectional view of the power conversion device according to Embodiment 8, taken along the cross-sectional line XXI-XXI shown in Figure 20. [Figure 22]It is a schematic cross-sectional view of the power conversion device according to Embodiment 8, taken along section line XXII-XXII shown in FIG. 20. [Figure 23] It is a schematic cross-sectional view of the power conversion device according to Embodiment 8, taken along section line XXIII-XXIII shown in FIG. 20. [Figure 24] It is a schematic cross-sectional view of the power conversion device according to Embodiment 9. [Figure 25] It is a schematic cross-sectional view of the power conversion device according to Embodiment 10. [Figure 26] It is a schematic cross-sectional view of the power conversion device according to another modified example of Embodiment 10. [Figure 27] It is a schematic cross-sectional view of the power conversion device according to Embodiment 11. [Figure 28] It is a schematic cross-sectional view of the power conversion device according to a modified example of Embodiment 11. [Figure 29] It is a schematic cross-sectional view of the power conversion device according to Embodiment 12. [Figure 30] It is a schematic cross-sectional view of the power conversion device according to a modified example of Embodiment 12. [Figure 31] It is a schematic plan view of the power conversion device according to Embodiment 13. [Figure 32] It is a schematic cross-sectional view of the power conversion device according to Embodiment 13, taken along section line XXXII-XXXII shown in FIG. 31. [Figure 33] It is a schematic view of the power conversion device according to Embodiment 13, viewed from the direction of arrow XXXIII shown in FIG. 31. [Figure 34] It is a schematic plan view of the power conversion device according to a first modified example of Embodiment 13. [Figure 35] It is a schematic cross-sectional view of the power conversion device according to the first modified example of Embodiment 13, taken along section line XXXV-XXXV shown in FIG. 34. [Figure 36] It is a schematic view of the power conversion device according to the first modified example of Embodiment 13, viewed from the direction of arrow XXXVI shown in FIG. 34. [Figure 37] It is a schematic plan view of the power conversion device according to a second modified example of Embodiment 13. [Figure 38]This is a schematic cross-sectional view of a power conversion device according to a second modified example of Embodiment 13, taken along the cross-sectional line XXXVIII-XXXVIII shown in Figure 37. [Figure 39] This is a schematic view of a power conversion device according to a second modified example of Embodiment 13, taken from the direction of arrow XXXIX shown in Figure 37. [Figure 40] This is a schematic plan view of a power conversion device according to a third modified example of Embodiment 13. [Figure 41] This is a schematic cross-sectional view of the power conversion device according to the third modified example of Embodiment 13, along the cross-sectional line XLI-XLI shown in Figure 40. [Figure 42] This is a schematic view of a power conversion device according to a third modified example of Embodiment 13, taken from the direction of arrow XLII shown in Figure 40. [Figure 43] This is a schematic plan view of a power conversion device according to a fourth modified example of Embodiment 13. [Figure 44] This is a schematic cross-sectional view of the power conversion device according to the fourth modified example of Embodiment 13, along the cross-sectional line XLIV-XLIV shown in Figure 43. [Figure 45] This is a schematic view of the power conversion device according to the fourth modification of Embodiment 13, taken from the direction of the arrow XLV shown in Figure 43. [Figure 46] This is a schematic plan view of a power conversion device according to a fifth modified example of Embodiment 13. [Figure 47] This is a schematic cross-sectional view of the power conversion device according to the fifth modified example of Embodiment 13, along the cross-sectional line XLVII-XLVII shown in Figure 46. [Figure 48] This is a schematic view of the power conversion device according to the fifth modification of Embodiment 13, taken from the direction of arrow XLVIII shown in Figure 46. [Modes for carrying out the invention]

[0009] Embodiments of the present disclosure will be described below. The same components will be given the same reference numerals, and their descriptions will not be repeated.

[0010] Embodiment 1. Referring to Figure 1, an example of the circuit configuration of the power converter 1 of Embodiment 1 will be described. The power converter 1 comprises an inverter circuit 2, a transformer circuit 3, a rectifier circuit 4, a smoothing circuit 5, an input terminal 6, an output terminal 7, an input capacitor 8, and a control circuit 10. The power converter 1 is, for example, a DC-DC converter mounted in an electric vehicle. An input DC voltage of approximately 300V from, for example, a lithium-ion battery is input to the input terminal 6. The power converter 1 converts the input DC voltage to an output DC voltage of, for example, 12V to 15V. The output DC voltage is output from the output terminal 7. The output DC voltage is used, for example, to charge a lead-acid battery.

[0011] Input capacitor 8 is connected to input terminal 6 and inverter circuit 2. Input capacitor 8 reduces ripple voltage.

[0012] The inverter circuit 2 converts the input DC voltage received from the input terminal 6 into a first AC voltage. The inverter circuit 2 includes switching elements 9a, 9b, 9c, and 9d. The switching elements 9a, 9b, 9c, and 9d are power semiconductor devices such as metal oxide semiconductor field-effect transistors (MOSFETs) or insulated-gate bipolar transistors (IGBTs). The switching elements 9a, 9b, 9c, and 9d are formed from semiconductor materials such as silicon (Si), silicon carbide (SiC), or gallium nitride (GaN).

[0013] The control circuit 10 controls the switching elements 9a, 9b, 9c, and 9d included in the inverter circuit 2.

[0014] The transformer circuit 3 converts the first AC voltage output from the inverter circuit 2 into a second AC voltage. The transformer circuit 3 includes a transformer 11. The transformer 11 includes a primary winding 11a and a secondary winding 11b. The primary winding 11a is connected to the inverter circuit 2. The secondary winding 11b is connected to the rectifier circuit 4. The secondary winding 11b is magnetically coupled to the primary winding 11a. The ratio of the first AC voltage to the second AC voltage depends on the winding ratio between the primary winding 11a and the secondary winding 11b. The transformer 11 electrically insulates the input terminal 6 and the output terminal 7.

[0015] The rectifier circuit 4 converts the second AC voltage output from the transformer circuit 3 into an output DC voltage. The rectifier circuit 4 includes rectifier elements 12a and 12b. The rectifier elements 12a and 12b are power semiconductor elements such as diodes, MOS transistors, or thyristors. The rectifier elements 12a and 12b are formed from semiconductor materials such as Si, SiC, or GaN.

[0016] The smoothing circuit 5 is connected to the rectifier circuit 4 and the output terminal 7. The smoothing circuit 5 includes a smoothing reactor 13 and a smoothing capacitor 14. In the smoothing circuit 5, the output DC voltage converted by the rectifier circuit 4 is smoothed by the smoothing reactor 13 and the smoothing capacitor 14. As a result, the output DC voltage output from the output terminal 7 is stabilized.

[0017] In the power converter 1, the switching elements 9a, 9b, 9c, and 9d, the rectifier elements 12a and 12b, the transformer 11, and the smoothing reactor 13 are electronic components that generate a large amount of heat. The heat from these high-heat-generating electronic components makes the transformer 11 and the smoothing reactor 13 prone to failure. Therefore, the power converter 1 needs to be cooled.

[0018] Referring to Figures 2 to 4, the configuration of the power converter 1 of this embodiment will be described. The power converter 1 comprises a metal base substrate 30, a plurality of circuit components 21, 22, 23, a cooler 50, and a first heat transport member 40.

[0019] The metal base substrate 30 includes an end face 31, an end face 32 opposite to end face 31, a main surface 33, and a main surface 34 opposite to main surface 33. The end faces 31 and 32 are, for example, the end faces of the metal base substrate 30 in the longitudinal direction (e.g., the z direction). The longitudinal direction (e.g., the z direction) of the metal base substrate 30 is not particularly limited, but may be the direction of gravity. End face 31 is the distal end face of the metal base substrate 30 relative to the cooler 50. End face 32 is the proximal end face of the metal base substrate 30 relative to the cooler 50. End face 32 faces the cooler 50.

[0020] The main surfaces 33 and 34 extend in the longitudinal direction (e.g., z-direction) of the metal base substrate 30 and in the short direction (e.g., x-direction) of the metal base substrate 30 perpendicular to the longitudinal direction (e.g., z-direction). The main surfaces 33 and 34 are connected to the end surfaces 31 and 32, respectively. The main surfaces 33 and 34 are the end faces of the metal base substrate 30 in the thickness direction (e.g., y-direction).

[0021] Referring to Figure 4, the metal base substrate 30 includes a metal plate 36, an insulating layer 37, and a circuit pattern 38.

[0022] The metal plate 36 is formed of a metallic material such as copper, iron, aluminum, a copper alloy, or an aluminum alloy. The metal plate 36 has a thermal conductivity of, for example, 1.0 W / (m·K) or more. The metal plate 36 may have a thermal conductivity of 10.0 W / (m·K) or more, or 100.0 W / (m·K) or more. The metal plate 36 supports the multiple circuit components 21, 22, 23 and transfers the heat generated by the multiple circuit components 21, 22, 23 to the cooler 50. The metal plate 36 is, for example, a rigid substrate.

[0023] The insulating layer 37 has electrical insulating properties and is provided on the metal plate 36. The insulating layer 37 electrically insulates the circuit pattern 38 from the metal plate 36. The insulating layer 37 is formed of an insulating resin such as epoxy resin, glass fiber reinforced epoxy resin, or polyimide resin. To improve the thermal conductivity of the insulating layer 37, the insulating layer 37 may be formed of an insulating resin to which a thermally conductive filler such as silica filler, alumina filler, or aluminum nitride filler has been added.

[0024] The heat generated by the multiple circuit components 21, 22, and 23 is transferred to the metal plate 36 and the first heat transport member 40 through the insulating layer 37. Therefore, the thickness of the insulating layer 37 is preferably as thin as possible, as long as it does not adversely affect the electrical insulation capability of the insulating layer 37. The thickness of the insulating layer 37 is, for example, 1 μm or more and 2000 μm or less. The thickness of the insulating layer 37 may also be 1 μm or more and 200 μm or less.

[0025] The circuit pattern 38 is provided on the insulating layer 37. The circuit pattern 38 is formed of a conductive material such as a metal such as copper, nickel, gold, aluminum, silver, or tin, or an alloy containing these metals. The thickness of the circuit pattern 38 is, for example, 1 μm to 2000 μm.

[0026] Referring to Figures 2 to 4, the main surface 33 of the metal base substrate 30 is mainly formed by an insulating layer 37 and a circuit pattern 38. The main surface 34 of the metal base substrate 30 is formed by a metal plate 36.

[0027] Each of the circuit components 21, 22, and 23 includes at least one of the following, as shown in Figure 1: an input capacitor 8, switching elements 9a, 9b, 9c, and 9d, a transformer 11, rectifier elements 12a and 12b, a smoothing reactor 13, or a smoothing capacitor 14. The circuit components 21, 22, and 23 may further include other electronic components such as resistors. Each of the circuit components 21, 22, and 23 may also include wiring components (not shown), such as leads. The heat generated by the circuit components 21, 22, and 23 includes the heat generated by the wiring components.

[0028] Multiple circuit components 21, 22, and 23 are mounted on the main surface 33 of the metal base substrate 30. The circuit components 21, 22, and 23 are electrically connected to the circuit pattern 38. Specifically, the circuit components 21, 22, and 23 may be fixed to the circuit pattern 38 using a conductive bonding member 39 such as solder. The circuit components 21, 22, and 23 may also be fixed to the circuit pattern 38 by welding or crimping their wiring components (not shown) to the circuit pattern 38.

[0029] In a plan view of the main surface 33, the circuit components 21, 22, and 23 are arranged, for example, in a direction away from the cooler 50 (e.g., in the -z direction). The circuit components 21, 22, and 23 are arranged, for example, in a direction perpendicular to the end face 32 of the metal base substrate 30 facing the cooler 50 (e.g., in the z direction). The circuit components 21, 22, and 23 are arranged, for example, in a direction perpendicular to the end face 42 of the first heat transport member 40 facing the cooler 50 (e.g., in the z direction). Circuit component 21 is positioned furthest from the cooler 50 among the multiple circuit components 21, 22, and 23. Circuit component 23 is positioned closest to the cooler 50 among the multiple circuit components 21, 22, and 23. Circuit component 22 is positioned between circuit component 21 and circuit component 23.

[0030] Referring to Figures 2 and 3, the cooler 50 cools the power converter 1 by dissipating the heat generated by the multiple circuit components 21, 22, and 23 to the outside of the power converter 1. The cooler 50 includes a heat sink 51. The heat sink 51 is made of a metal such as copper, iron, aluminum, iron alloy, or aluminum alloy. The heat sink 51 has a thermal conductivity of, for example, 1.0 W / (m·K) or more. The heat sink 51 may have a thermal conductivity of 10.0 W / (m·K) or more, or a thermal conductivity of 100.0 W / (m·K) or more. The heat sink 51 dissipates the heat generated by the multiple circuit components 21, 22, and 23 into the air surrounding the heat sink 51.

[0031] A cooler circulating path may be formed in the cooler 50. The cooler 50 may further include a cooling pipe 52 that penetrates the heat sink 51 as a coolant circulating path. A coolant such as air or water flows through the cooling pipe 52. The heat generated by the multiple circuit components 21, 22, and 23 is carried out of the power converter 1 by the coolant. For example, the cooling pipe 52 is connected to a coolant circulation device (not shown) via a hose (not shown). The hose is, for example, a flexible resin hose. If the coolant is water, the coolant circulation device is, for example, a cooling water circulation device. The coolant circulation device supplies coolant at a constant temperature to the cooling pipe 52 at a constant flow rate.

[0032] The cooler 50 is thermally connected to the end face 32 of the metal base substrate 30. In this specification, thermal connection of member A to member B means that member A is in direct contact with member B, or is connected via a thermal conductive member having a thermal conductivity of 0.5 W / (m·K) or more. Examples of such thermal conductive members include thermal conductive grease, thermal conductive sheets, or thermal conductive adhesives. The cooler 50 is fixed to the end face 32 of the metal base substrate 30 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0033] The first heat transport member 40 transports or diffuses the heat generated by the multiple circuit components 21, 22, and 23 to the cooler 50.

[0034] The first heat transport member 40 includes an end face 41, an end face 42 opposite to end face 41, a main face 43, and a main face 44 opposite to main face 43. The end faces 41 and 42 are, for example, the end faces of the first heat transport member 40 in the longitudinal direction (e.g., the z direction). The longitudinal direction (e.g., the z direction) of the first heat transport member 40 is not particularly limited, but may be the direction of gravity. End face 41 is the distal end face of the first heat transport member 40 relative to the cooler 50. End face 42 is the proximal end face of the first heat transport member 40 relative to the cooler 50. End face 42 faces the cooler 50. The main faces 43 and 44 are connected to the end faces 41 and 42, respectively. The main faces 43 and 44 are the end faces of the first heat transport member 40 in the thickness direction (e.g., the y direction).

[0035] The main surface 43 of the first heat transport member 40 is thermally connected to the main surface 34 of the metal base substrate 30. The main surface 43 of the first heat transport member 40 is fixed to the main surface 34 of the metal base substrate 30 by crimping, pressure welding, soldering, brazing, bonding, or welding. The end surface 42 of the first heat transport member 40 is thermally connected to the cooler 50. The end surface 42 of the first heat transport member 40 is fixed to the cooler 50 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0036] In a plan view of the main surface 33, the first heat transport member 40 extends from the end face 32 of the metal base substrate 30 to the end face 31 of the metal base substrate 30. The end face 41 of the first heat transport member 40 may be flush with the end face 31 of the metal base substrate 30. The end face 42 of the first heat transport member 40 may be flush with the end face 32 of the metal base substrate 30. In a plan view of the main surface 33, the first heat transport member 40 overlaps with a plurality of circuit components 21, 22, and 23. In a plan view of the main surface 33, the first heat transport member 40 may overlap the entire metal base substrate 30.

[0037] The cross-sectional area of ​​the first heat transport member 40 may be larger than the cross-sectional area of ​​the metal base substrate 30. The cross-sectional area of ​​the first heat transport member 40 may be larger than the cross-sectional area of ​​the metal plate 36. The cross-sectional area of ​​the first heat transport member 40 is the cross-sectional area of ​​the first heat transport member 40 in a cross section perpendicular to the direction in which the heat generated by the multiple circuit components 21, 22, 23 is mainly transferred (for example, the z-direction). The cross-sectional area of ​​the metal base substrate 30 is the cross-sectional area of ​​the metal base substrate 30 in a cross section perpendicular to the direction in which the heat generated by the multiple circuit components 21, 22, 23 is mainly transferred (for example, the z-direction). The cross-sectional area of ​​the metal plate 36 is the cross-sectional area of ​​the metal plate 36 in a cross section perpendicular to the direction in which the heat generated by the multiple circuit components 21, 22, 23 is mainly transferred (for example, the z-direction).

[0038] The thermal conductivity of the first heat transport member 40 is equal to or higher than the thermal conductivity of the metal plate 36. The first heat transport member 40 is, for example, a heat pipe, a vapor chamber, or a graphite sheet, or a metal plate integrated with any of these. The first heat transport member 40 is formed of a metallic material such as copper, iron, aluminum, an iron alloy or an aluminum alloy, or carbon. The first heat transport member 40 has a thermal conductivity of, for example, 1.0 W / (m·K) or more. The first heat transport member 40 may have a thermal conductivity of 10.0 W / (m·K) or more, or a thermal conductivity of 100.0 W / (m·K) or more.

[0039] To enhance heat transport capacity, a capillary structure is formed on the inner wall of the heat pipe. Therefore, bending the heat pipe causes the capillary structure to collapse, reducing the heat transport capacity of the heat pipe. However, in this embodiment, when the first heat transport member 40 is a heat pipe, the heat pipe can be used without bending it. Therefore, a decrease in the heat transport capacity of the heat pipe can be prevented. Furthermore, when the first heat transport member 40 is a heat pipe and the longitudinal direction of the first heat transport member 40 is in the direction of gravity, the performance of the heat pipe is improved, and the cooler 50 can be miniaturized.

[0040] The operation of the power converter 1 of this embodiment will now be explained. The heat generated by the multiple circuit components 21, 22, and 23 is transferred to the cooler 50 by both the metal base substrate 30 and the first heat transport member 40. Therefore, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is reduced. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be miniaturized.

[0041] In the comparative example where the cooler 50 is thermally connected to the main surface 34 of the metal base substrate 30, as the number of circuit components 21, 22, 23 increases and the size of the metal base substrate 30 increases, the size of the cooler 50 also increases. In contrast, in this embodiment, the cooler 50 is thermally connected not to the main surface 34 of the metal base substrate 30, but to the end surface 32 of the metal base substrate 30 and the end surface 42 of the first heat transport member 40. Therefore, the heat generated by the circuit components 21, 22, 23 is concentrated in the cooler 50 by the metal base substrate 30 and the first heat transport member 40. Even if the number of circuit components 21, 22, 23 increases and the size of the metal base substrate 30 increases, there is no need to increase the size of the cooler 50.

[0042] The power converter 1 includes a first heat transport member 40 in addition to the metal base substrate 30. As a result, the difference between the thermal resistance of the heat transfer path from the circuit component 21, 22, 23 located further from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from the circuit component 23 located closer to the cooler 50 to the cooler 50 is reduced. The power converter 1 can cool the circuit components 21, 22, 23 more uniformly. Circuit components that generate more heat can be used as the circuit component located further from the cooler 50 (e.g., circuit component 21). The degree of freedom in the arrangement of circuit components 21, 22, 23 is improved. The thermal design of the power converter 1 becomes easier.

[0043] In a plan view of the main surface 33, the circuit components 21, 22, and 23 are arranged perpendicular to the end face 32 of the metal base substrate 30 facing the cooler 50 (for example, in the z-direction). Therefore, in a plan view of the main surface 33, the size of the metal base substrate 30 in the direction along the end face 32 of the metal base substrate 30 (for example, in the x-direction) is reduced. In a plan view of the main surface 33, the size of the cooler 50 in the direction along the end face 32 of the metal base substrate 30 (for example, in the x-direction) is reduced.

[0044] The effects of the power converter 1 of this embodiment will be explained. The power converter 1 comprises a plurality of circuit components 21, 22, 23, a metal base substrate 30 including a metal plate 36, a first heat transport member 40, and a cooler 50. The metal base substrate 30 includes a first main surface (main surface 33) on which the plurality of circuit components 21, 22, 23 are mounted, and a first end surface (end surface 32) connected to the first main surface. The thermal conductivity of the first heat transport member 40 is greater than or equal to the thermal conductivity of the metal plate 36. The first heat transport member 40 includes a second main surface (main surface 43) and a second end surface (end surface 42) connected to the second main surface and facing the cooler 50. The first and second end surfaces are thermally connected to the cooler 50. The second main surface is thermally connected to the metal base substrate 30.

[0045] Therefore, the heat generated by the multiple circuit components 21, 22, and 23 is transferred to the cooler 50 by both the metal base substrate 30 and the first heat transport member 40. The cooler 50 is thermally connected to the first end face (end face 32) of the metal base substrate 30 and the second end face (end face 42) of the first heat transport member 40. The heat generated by the multiple circuit components 21, 22, and 23 is concentrated in the cooler 50 by the metal base substrate 30 and the first heat transport member 40. Even if the number of multiple circuit components 21, 22, and 23 increases and the size of the metal base substrate 30 increases, the multiple circuit components 21, 22, and 23 can be cooled without increasing the size of the cooler 50.

[0046] In the power converter 1, the metal base substrate 30 includes a third end face (end face 31) opposite to the first end face (end face 32). In a plan view of the first main surface (main surface 33), the first heat transport member 40 extends from the first end face to the third end face.

[0047] Therefore, heat generated by circuit components located far from the cooler 50 (e.g., circuit component 21) can be transferred to the cooler 50 with lower thermal resistance. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1 becomes easier. The cooler 50 can be made smaller.

[0048] Embodiment 2. Referring to Figure 5, the power converter 1b according to Embodiment 2 will be described. The power converter 1b of this embodiment has the same configuration as the power converter 1 of Embodiment 1, but differs mainly in the following points.

[0049] The first heat transport member 40 is curved relative to the metal base substrate 30. An air layer 55 exists between the metal base substrate 30 and the first heat transport member 40. As you move away from the cooler 50 (i.e., as you move from end face 42 towards end face 41), the distance between the metal base substrate 30 and the first heat transport member 40 decreases. The distance between end face 32 and end face 42 is greater than the distance between end face 31 and end face 41. The distance between end face 32 and end face 42 is, for example, 10 μm or less. The distance between end face 31 and end face 41 is, for example, 0 μm.

[0050] As shown in Figure 2, in a plan view of the main surface 33, in the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction), the length of the heat transfer path from the circuit components to the cooler 50 increases as the distance from the cooler 50 increases. Conversely, the thickness of the air layer 55 decreases as the distance from the cooler 50 increases. Some of the heat generated by the circuit components 21, 22, 23 that are located further from the cooler 50 is transferred to the cooler 50 through the first heat transport member 40 and the thinner air layer 55. The thermal conductivity of the air layer 55 is greater than that of the metal base substrate 30 and the first heat transport member 40. Therefore, the difference between the thermal resistance of the heat transfer path from the circuit components located further from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from the circuit components located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 decreases.

[0051] In addition to the effects of the power converter 1 of Embodiment 1, the power converter 1b of this embodiment has the following effects.

[0052] In the power converter 1b, the distance between the metal base substrate 30 and the first heat transport member 40 decreases as the distance from the cooler 50 increases.

[0053] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. The power converter 1b can cool the multiple circuit components 21, 22, and 23 more uniformly. Among the multiple circuit components 21, 22, and 23, the circuit component located further away from the cooler 50 (e.g., circuit component 21) can be a circuit component that generates more heat. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1b becomes easier.

[0054] Embodiment 3. Referring to Figure 6, the power converter 1c according to Embodiment 3 will be described. The power converter 1c of this embodiment has the same configuration as the power converter 1 of Embodiment 1, but differs mainly in the following points.

[0055] In the power converter 1c, the contact area between the metal base substrate 30 and the first heat transport member 40 increases as you move away from the cooler 50 (i.e., as you move from the end face 42 towards the end face 41). For example, the surface roughness of the main surface 34 of the first heat transport member 40 decreases as you move away from the cooler 50.

[0056] As shown in Figure 2, in a plan view of the main surface 33, in the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction), the length of the heat transfer path from the circuit components to the cooler 50 increases as they move away from the cooler 50. Conversely, as the contact area between the metal base substrate 30 and the first heat transport member 40 increases, the thermal resistance between the metal base substrate 30 and the first heat transport member 40 decreases. Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 decreases.

[0057] In addition to the effects of the power converter 1 of Embodiment 1, the power converter 1c of this embodiment has the following effects.

[0058] In the power converter 1c, the contact area between the metal base substrate 30 and the first heat transport member 40 increases as it moves away from the cooler 50.

[0059] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. The power converter 1c can cool the multiple circuit components 21, 22, and 23 more uniformly. Among the multiple circuit components 21, 22, and 23, the circuit component located further away from the cooler 50 (e.g., circuit component 21) can be a circuit component that generates more heat. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1c becomes easier.

[0060] Embodiment 4. Referring to Figures 7 to 9, the power converter 1d according to Embodiment 4 will be described. The power converter 1d of this embodiment has the same configuration as the power converter 1 of Embodiment 1, but differs mainly in the following points.

[0061] In the power converter 1d, the first heat transport member 40 includes a plurality of heat transport sections 45, 46. The heat transport sections 45 and 46 are each thermally connected to the main surface 34 of the metal base substrate 30. The heat transport sections 45 and 46 are each fixed to the main surface 34 of the metal base substrate 30 by crimping, pressure welding, soldering, brazing, bonding, or welding. The main surface 43 of the first heat transport member 40 is composed of the main surface of the heat transport section 45 facing the main surface 34 of the metal base substrate 30 and the main surface of the heat transport section 46 facing the main surface 34 of the metal base substrate 30. The heat transport sections 45 and 46 are each thermally connected to the cooler 50. The heat transport sections 45 and 46 are each fixed to the cooler 50 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0062] In a plan view of the main surface 33, the heat transport portions 45 and 46 each extend from the end face 32 of the metal base substrate 30 to the end face 31 of the metal base substrate 30. The distal end face of the heat transport portion 45 to the cooler 50 and the distal end face of the heat transport portion 46 to the cooler 50 may be flush with the end face 31 of the metal base substrate 30. The proximal end face of the heat transport portion 45 to the cooler 50 and the proximal end face of the heat transport portion 46 to the cooler 50 may be flush with the end face 32 of the metal base substrate 30. The end face 41 of the first heat transport member 40 is composed of the distal end face of the heat transport portion 45 to the cooler 50 and the distal end face of the heat transport portion 46 to the cooler 50. The end face 42 of the first heat transport member 40 is composed of the proximal end face of the heat transport portion 45 to the cooler 50 and the proximal end face of the heat transport portion 46 to the cooler 50.

[0063] In the power converter 1d, in a plan view of the main surface 33, the first heat transport member 40 does not overlap with the multiple circuit components 21, 22, 23. Specifically, in a plan view of the main surface 33, the heat transport portions 45 and 46 do not overlap with the multiple circuit components 21, 22, 23. In a plan view of the main surface 33, the multiple circuit components 21, 22, 23 are positioned between the heat transport portion 45 and the heat transport portion 46. In a plan view of the main surface 33, the heat transport portion 45 and the heat transport portion 46 may be positioned symmetrically with respect to the multiple circuit components 21, 22, 23. In a plan view of the main surface 33, the distance between the multiple circuit components 21, 22, 23 and the heat transport portion 45 may be equal to the distance between the multiple circuit components 21, 22, 23 and the heat transport portion 46.

[0064] The power converter 1d further comprises a metal support member 60. The metal support member 60 includes an end face 61, an end face 62 opposite to end face 61, and a main surface 63. The end faces 61 and 62 are, for example, the end faces of the metal support member 60 in the longitudinal direction (e.g., the z direction). The longitudinal direction (e.g., the z direction) of the metal support member 60 is not particularly limited, but may be the direction of gravity. End face 61 is the distal end face of the metal support member 60 relative to the cooler 50. End face 62 is the proximal end face of the metal support member 60 relative to the cooler 50. End face 62 faces the cooler 50. The main surface 63 is connected to the end faces 61 and 62. The main surface 63 is the end face of the metal support member 60 in the thickness direction (e.g., the y direction). The main surface 63 faces the main surface 44 of the first heat transport member 40.

[0065] The metal support member 60 supports the first heat transport member 40. Specifically, grooves 65 and 66 are provided on the main surface 63. The heat transport portion 45 is housed in groove 65. The heat transport portion 46 is housed in groove 66. The main surface 63 of the metal support member 60 may be flush with the main surface of the heat transport portion 45 facing the main surface 34 of the metal base substrate 30, and with the main surface of the heat transport portion 46 facing the main surface 34 of the metal base substrate 30.

[0066] The first heat transport member 40 is thermally connected to the metal support member 60. The first heat transport member 40 is fixed to the metal support member 60 by crimping, pressure welding, soldering, brazing, bonding, or welding. The heat transport portions 45 and 46 are thermally connected to the metal support member 60. The heat transport portions 45 and 46 are fixed to the metal support member 60 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0067] The main surface 63 of the metal support member 60 is thermally connected to the main surface 34 of the metal base substrate 30. The main surface 63 of the metal support member 60 is fixed to the main surface 34 of the metal base substrate 30 by crimping, pressure welding, soldering, brazing, bonding, or welding. The end surface 62 of the metal support member 60 is thermally connected to the cooler 50. The end surface 62 of the metal support member 60 is fixed to the cooler 50 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0068] In a plan view of the main surface 33, the metal support member 60 overlaps with a plurality of circuit components 21, 22, and 23. In a plan view of the main surface 33, the metal support member 60 may overlap the entire metal base substrate 30 and the entire first heat transport member 40. In a plan view of the main surface 33, the metal support member 60 extends from the end face 32 of the metal base substrate 30 to the end face 31 of the metal base substrate 30. In a plan view of the main surface 33, the metal support member 60 extends from the end face 42 of the first heat transport member 40 to the end face 41 of the first heat transport member 40.

[0069] The cross-sectional area of ​​the metal support member 60 may be larger than the cross-sectional area of ​​the metal base substrate 30. The cross-sectional area of ​​the metal support member 60 may be larger than the cross-sectional area of ​​the metal plate 36. The cross-sectional area of ​​the metal support member 60 may be larger than the cross-sectional area of ​​the first heat transport member 40. The cross-sectional area of ​​the metal support member 60 is the cross-sectional area of ​​the metal support member 60 in a section perpendicular to the direction (for example, the z-direction) in which the heat generated by the plurality of circuit components 21, 22, 23 is mainly transferred.

[0070] The thermal conductivity of the metal support member 60 is equal to or higher than that of the metal plate 36. The thermal conductivity of the metal support member 60 is equal to or lower than that of the first heat transport member 40. The metal support member 60 is formed of a metallic material such as copper, iron, aluminum, iron alloy, or aluminum alloy. The metal support member 60 has a thermal conductivity of, for example, 1.0 W / (m·K) or more. The metal support member 60 may have a thermal conductivity of 10.0 W / (m·K) or more, or a thermal conductivity of 100.0 W / (m·K) or more. The metal support member 60 transfers the heat generated by the multiple circuit components 21, 22, and 23 to the cooler 50. The metal support member 60 is, for example, a rigid plate.

[0071] In addition to the effects of the power converter 1 of Embodiment 1, the power converter 1d of this embodiment has the following effects.

[0072] The power converter 1d further comprises a metal support member 60 that supports the first heat transport member 40. The metal base substrate 30 includes a third main surface (main surface 34) opposite to the first main surface (main surface 33). The third main surface is connected to the first end surface (end surface 32). The metal support member 60 includes a fourth main surface (main surface 63) thermally connected to the third main surface and a fourth end surface (end surface 62) connected to the fourth main surface. The fourth end surface is thermally connected to the cooler 50.

[0073] Therefore, the heat generated by the multiple circuit components 21, 22, and 23 is transferred to the cooler 50 not only by the metal base substrate 30 and the first heat transport member 40, but also by the metal support member 60. The thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is reduced. Furthermore, the cooler 50 is thermally connected to the first end face (end face 32) of the metal base substrate 30, the second end face (end face 42) of the first heat transport member 40, and the fourth end face (end face 62) of the metal support member 60. The heat generated by the multiple circuit components 21, 22, and 23 is concentrated in the cooler 50 by the metal base substrate 30, the first heat transport member 40, and the metal support member 60. Even if the number of multiple circuit components 21, 22, and 23 increases and the size of the metal base substrate 30 increases, the multiple circuit components 21, 22, and 23 can be cooled without increasing the size of the cooler 50.

[0074] In the power converter 1d, in addition to the second end face (end face 42) of the first heat transport member 40, the fourth end face (end face 62) of the metal support member 60 that supports the first heat transport member 40 is also thermally connected to the cooler 50. Therefore, fixing the first heat transport member 40 to the cooler 50 becomes easier. Furthermore, if the metal support member 60 is a rigid plate, the mechanical strength of the power converter 1d is improved.

[0075] Embodiment 5. The power converter 1e according to Embodiment 5 will be described with reference to Figures 10 and 11. The power converter 1e of this embodiment has a similar configuration to the power converter 1d of Embodiment 4, but differs mainly in the following points.

[0076] The power converter 1e further comprises circuit components 24, 25, and 26. In a plan view of the main surface 33, the circuit components 24, 25, and 26 are arranged, for example, in the direction away from the cooler 50 (-z direction). In a plan view of the main surface 33, the circuit components 24, 25, and 26 are arranged, for example, in the longitudinal direction of the metal base substrate 30 (e.g., z direction). In a plan view of the main surface 33, the circuit components 24, 25, and 26 are arranged, for example, in the direction perpendicular to the end face 32 of the metal base substrate 30 (e.g., z direction). In a plan view of the main surface 33, the circuit components 24, 25, and 26 are arranged, for example, in the direction perpendicular to the end face 42 of the first heat transport member 40 (e.g., z direction).

[0077] Circuit component 24 is positioned furthest from the cooler 50 among circuit components 24, 25, and 26. Circuit component 26 is positioned closest to the cooler 50 among circuit components 24, 25, and 26. Circuit component 25 is positioned between circuit components 24 and 26. Circuit components 24, 25, and 26 are positioned offset from circuit components 21, 22, and 23 in the short-side direction (e.g., x-direction) of the metal base substrate 30.

[0078] Each of the circuit components 24, 25, and 26 includes at least one of the input capacitor 8, switching elements 9a, 9b, 9c, and 9d, transformer 11, rectifier elements 12a and 12b, and smoothing reactor 13 or smoothing capacitor 14, as shown in Figure 1. The circuit components 24, 25, and 26 may further include other electronic components such as resistors. Each of the circuit components 24, 25, and 26 may also include wiring components (not shown), such as leads. The heat generated by the multiple circuit components 24, 25, and 26 includes the heat generated by the wiring components.

[0079] In a plan view of the main surface 33, the first heat transport member 40 overlaps with multiple circuit components 21, 22, 23, 24, 25, and 26. Specifically, in a plan view of the main surface 33, the heat transport portion 45 overlaps with circuit components 21, 22, and 23. In a plan view of the main surface 33, the heat transport portion 46 overlaps with circuit components 24, 25, and 26.

[0080] In addition to the effects of the power converter 1d of Embodiment 4, the power converter 1e of this embodiment has the following effects.

[0081] In the power converter 1e, in a plan view of the first main surface (main surface 33), multiple circuit components 21, 22, 23, 24, 25, and 26 overlap the first heat transport member 40.

[0082] Therefore, the heat transfer path from the multiple circuit components 21, 22, 23, 24, 25, 26 to the cooler 50 is shortened, and the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, 23, 24, 25, 26 to the cooler 50 is reduced. Even if the number of multiple circuit components 21, 22, 23, 24, 25, 26 increases and the size of the metal base substrate 30 increases, the multiple circuit components 21, 22, 23, 24, 25, 26 can be cooled without increasing the size of the cooler 50.

[0083] Embodiment 6. Referring to Figures 12 to 15, the power converter 1f according to Embodiment 6 will be described. The power converter 1f of this embodiment has the same configuration as the power converter 1d of Embodiment 4, but differs mainly in the following points.

[0084] The first heat transport member 40 includes a heat transport portion 47 in addition to the heat transport portions 45 and 46. The heat transport portion 47 is also thermally connected to the main surface 34 of the metal base substrate 30. The heat transport portion 47 is fixed to the main surface 34 of the metal base substrate 30 by crimping, pressure welding, soldering, brazing, bonding, or welding. The main surface 43 of the first heat transport member 40 is composed of the main surface of the heat transport portion 45 facing the main surface 34 of the metal base substrate 30, the main surface of the heat transport portion 46 facing the main surface 34 of the metal base substrate 30, and the main surface of the heat transport portion 47 facing the main surface 34 of the metal base substrate 30. The heat transport portion 47 is also thermally connected to the cooler 50. The heat transport portion 47 is fixed to the cooler 50 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0085] In a plan view of the main surface 33, the heat transport portion 47 also extends from the end face 32 of the metal base substrate 30 to the end face 31 of the metal base substrate 30. The distal end face of the heat transport portion 47 to the cooler 50 may be flush with the end face 31 of the metal base substrate 30. The proximal end face of the heat transport portion 47 to the cooler 50 may be flush with the end face 32 of the metal base substrate 30. The end face 41 of the first heat transport member 40 is composed of the distal end face of the heat transport portion 45 to the cooler 50, the distal end face of the heat transport portion 46 to the cooler 50, and the distal end face of the heat transport portion 47 to the cooler 50. The end face 42 of the first heat transport member 40 is composed of the proximal end face of the heat transport portion 45 to the cooler 50, the proximal end face of the heat transport portion 46 to the cooler 50, and the proximal end face of the heat transport portion 47 to the cooler 50.

[0086] In a plan view of the main surface 33, a portion of the first heat transport member 40 overlaps with multiple circuit components 21, 22, and 23. For example, in a plan view of the main surface 33, the heat transport portion 47 overlaps with multiple circuit components 21, 22, and 23.

[0087] The metal support member 60 also supports the heat transport portion 47. Specifically, a groove 67 is provided on the main surface 63. The heat transport portion 47 is housed in the groove 67. The main surface 63 of the metal support member 60 may be flush with the main surface of the heat transport portion 47 that faces the main surface 34 of the metal base substrate 30. The heat transport portion 47 is also thermally connected to the metal support member 60. The heat transport portion 47 is fixed to the metal support member 60 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0088] In a plan view of the main surface 33, the heat transport portion 45 includes a side surface 45s facing a plurality of circuit components 21, 22, 23. In a plan view of the main surface 33, the heat transport portion 46 includes a side surface 46s facing a plurality of circuit components 21, 22, 23. In a plan view of the main surface 33, the heat transport portion 45 and the heat transport portion 46 may be arranged symmetrically with respect to the heat transport portion 47. In a plan view of the main surface 33, the heat transport portion 45 and the heat transport portion 46 may be arranged symmetrically with respect to the plurality of circuit components 21, 22, 23.

[0089] In a plan view of the main surface 33, the distance between the multiple circuit components 21, 22, 23 and the heat transport portion 45 decreases as the distance from the cooler 50 increases. Specifically, in a plan view of the main surface 33, the side surface 45s of the heat transport portion 45 approaches the multiple circuit components 21, 22, 23 as the distance from the cooler 50 increases. In a plan view of the main surface 33, the side surface 45s of the heat transport portion 45 is inclined with respect to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction). In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction) (e.g., the x direction), the distance between circuit component 22 and the heat transport portion 45 is smaller than the distance between circuit component 23 and the heat transport portion 45. In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, and 23 are arranged (e.g., the z-direction) (e.g., the x-direction), the distance between circuit component 21 and the heat transport portion 45 is smaller than the distance between circuit component 22 and the heat transport portion 45.

[0090] In a plan view of the main surface 33, the distance between the multiple circuit components 21, 22, 23 and the heat transport portion 46 decreases as the distance from the cooler 50 increases. Specifically, in a plan view of the main surface 33, the side surface 46s of the heat transport portion 46 approaches the multiple circuit components 21, 22, 23 as the distance from the cooler 50 increases. In a plan view of the main surface 33, the side surface 46s of the heat transport portion 46 is inclined with respect to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction). In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction) (e.g., the x direction), the distance between circuit component 22 and the heat transport portion 46 is smaller than the distance between circuit component 23 and the heat transport portion 46. In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, and 23 are arranged (e.g., the z-direction) (e.g., the x-direction), the distance between circuit component 21 and the heat transport portion 46 is smaller than the distance between circuit component 22 and the heat transport portion 46.

[0091] In a plan view of the main surface 33, in the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction), the length of the heat transfer path from the circuit components to the cooler 50 increases as it moves away from the cooler 50. In contrast, in a direction perpendicular to the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction) in a plan view of the main surface 33 (e.g., the x-direction), the distance between the circuit components and at least one of the multiple heat transport parts 45, 46, 47 (e.g., heat transport parts 45, 46) decreases as it moves away from the cooler 50. Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 decreases.

[0092] In this modified embodiment, in a plan view of the main surface 33, the heat transport portions 45 and 46 may overlap with at least one of the circuit components 21, 22, and 23.

[0093] In addition to the effects of the power converter 1d of Embodiment 4, the power converter 1f of this embodiment has the following effects.

[0094] In the power converter 1f, the first heat transport member 40 includes a plurality of heat transport sections 45, 46, and 47. Each of the plurality of heat transport sections 45, 46, and 47 is thermally connected to the metal base substrate 30 and the cooler 50. As the distance from the cooler 50 increases, the distance between the plurality of circuit components 21, 22, and 23 and at least one of the plurality of heat transport sections 45, 46, and 47 (for example, heat transport section 45, 46) decreases.

[0095] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. The power converter 1f can cool the multiple circuit components 21, 22, and 23 more uniformly. Among the multiple circuit components 21, 22, and 23, the circuit component located further away from the cooler 50 (e.g., circuit component 21) can be a circuit component that generates more heat. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1f becomes easier.

[0096] The power converter 1f includes more heat transport parts 45, 46, and 47. Therefore, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is reduced. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0097] In the power converter 1f, in a plan view of the first main surface (main surface 33), as you move away from the cooler 50, the side surface (e.g., side surface 45s, 46s) of at least one of the heat transport parts 45, 46, 47 facing the circuit components 21, 22, 23 (e.g., heat transport parts 45, 46) approaches the circuit components 21, 22, 23.

[0098] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. The power converter 1f can cool the multiple circuit components 21, 22, and 23 more uniformly. Among the multiple circuit components 21, 22, and 23, the circuit component located further away from the cooler 50 (e.g., circuit component 21) can be a circuit component that generates more heat. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1f becomes easier.

[0099] In the power converter 1f, in a plan view of the first main surface (main surface 33), the multiple circuit components 21, 22, and 23 are arranged in a direction away from the cooler 50 (for example, in the -z direction). In a plan view of the first main surface, at least one of the multiple heat transport sections 45, 46, and 47 (for example, heat transport sections 45 and 46) is inclined with respect to the direction in which the multiple circuit components 21, 22, and 23 are arranged.

[0100] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. Among the multiple circuit components 21, 22, and 23, a circuit component with a larger heat generation can be used as the circuit component located further away from the cooler 50 (e.g., circuit component 21). The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1f becomes easier.

[0101] Embodiment 7. The power converter 1g according to Embodiment 7 will be described with reference to Figures 16 to 19. The power converter 1g of this embodiment has the same configuration as the power converter 1f of Embodiment 6, but differs mainly in the following points.

[0102] In a plan view of the main surface 33, the width of the heat transport portion 45 increases as it moves away from the cooler 50. The side surface 45s of the heat transport portion 45 is inclined with respect to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z-direction). Therefore, in a plan view of the main surface 33, the distance between the multiple circuit components 21, 22, 23 and the heat transport portion 45 decreases as it moves away from the cooler 50. In a plan view of the main surface 33, the side surface 45s of the heat transport portion 45 approaches the multiple circuit components 21, 22, 23 as it moves away from the cooler 50.

[0103] In a plan view of the main surface 33, the width of the heat transport portion 46 increases as it moves away from the cooler 50. The side surface 46s of the heat transport portion 46 is inclined with respect to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z-direction). Therefore, in a plan view of the main surface 33, the distance between the multiple circuit components 21, 22, 23 and the heat transport portion 46 decreases as it moves away from the cooler 50. In a plan view of the main surface 33, the side surface 46s of the heat transport portion 46 approaches the multiple circuit components 21, 22, 23 as it moves away from the cooler 50.

[0104] In a plan view of the main surface 33, in the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction), the length of the heat transfer path from the circuit components to the cooler 50 increases as it moves away from the cooler 50. In contrast, in a direction perpendicular to the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction) in a plan view of the main surface 33 (e.g., the x-direction), the distance between the circuit components and at least one of the multiple heat transport parts 45, 46, 47 (e.g., heat transport parts 45, 46) decreases as it moves away from the cooler 50. Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 decreases.

[0105] The power converter 1g of this embodiment provides the same effects as the power converter 1f of Embodiment 6.

[0106] In the power converter 1g, in a plan view of the first main surface (main surface 33), the width of at least one of the multiple heat transport sections 45, 46, 47 (e.g., heat transport sections 45, 46) increases as it moves away from the cooler 50.

[0107] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. The power converter 1g can cool the multiple circuit components 21, 22, and 23 more uniformly. Among the multiple circuit components 21, 22, and 23, the circuit component located further away from the cooler 50 (e.g., circuit component 21) can be a circuit component that generates more heat. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1g becomes easier.

[0108] In the power converter 1g, in a plan view of the first main surface (main surface 33), the multiple circuit components 21, 22, and 23 are arranged in a direction away from the cooler 50 (-z direction). In a plan view of the first main surface, the side surface (e.g., side surfaces 45s, 46s) of at least one of the multiple heat transport sections 45, 46, and 47 (e.g., heat transport section 45, 46) is inclined with respect to the direction in which the multiple circuit components 21, 22, and 23 are arranged.

[0109] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. The power converter 1g can cool the multiple circuit components 21, 22, and 23 more uniformly. Among the multiple circuit components 21, 22, and 23, the circuit component located further away from the cooler 50 (e.g., circuit component 21) can be a circuit component that generates more heat. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1g becomes easier.

[0110] Embodiment 8. The power converter 1h according to Embodiment 8 will be described with reference to Figures 20 to 23. The power converter 1h of this embodiment has the same configuration as the power converter 1g of Embodiment 7, but differs mainly in the following points.

[0111] In a plan view of the main surface 33, the side surface 45s of the heat transport portion 45 has a stepped shape. Therefore, in a plan view of the main surface 33, the width of the heat transport portion 45 increases as it moves away from the cooler 50. In a plan view of the main surface 33, the distance between the multiple circuit components 21, 22, 23 and the heat transport portion 45 decreases as it moves away from the cooler 50. In a plan view of the main surface 33, the side surface 45s of the heat transport portion 45 approaches the multiple circuit components 21, 22, 23 as it moves away from the cooler 50.

[0112] Specifically, the heat transport section 45 includes heat transport elements 45a, 45b, and 45c. In a plan view of the main surface 33, heat transport element 45a faces circuit component 21 but not circuit components 22 and 23. In a plan view of the main surface 33, heat transport element 45b faces circuit components 21 and 22 but not circuit component 23. In a plan view of the main surface 33, heat transport element 45c faces circuit components 21, 22, and 23.

[0113] In a plan view of the main surface 33, the heat transport element 45c is longer than the heat transport elements 45a and 45b. In a plan view of the main surface 33, the heat transport element 45b is longer than the heat transport element 45a. The distal end face of the heat transport element 45a relative to the cooler 50 may be flush with the end face 31 of the metal base substrate 30. The distal end face of the heat transport element 45b relative to the cooler 50 may be flush with the end face 31 of the metal base substrate 30. The distal end face of the heat transport element 45c relative to the cooler 50 may be flush with the end face 31 of the metal base substrate 30. The proximal end face of the heat transport element 45a relative to the cooler 50 is separated from the end face 32 of the metal base substrate 30. The proximal end face of the heat transport element 45b relative to the cooler 50 is separated from the end face 32 of the metal base substrate 30. The proximal end face of the heat transport element 45c relative to the cooler 50 may be flush with the end face 32 of the metal base substrate 30.

[0114] In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction) (e.g., the x direction), heat transport element 45a is positioned closest to the multiple circuit components 21, 22, 23 among heat transport elements 45a, 45b, and 45c. In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction) (e.g., the x direction), heat transport element 45c is positioned furthest from the multiple circuit components 21, 22, 23 among heat transport elements 45a, 45b, and 45c. In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction) (e.g., the x direction), heat transport element 45b is positioned between heat transport element 45a and heat transport element 45c. The heat transport element 45b is thermally connected to the heat transport elements 45a and 45c. The heat transport elements 45a, 45b, and 45c are integrated and may be a single component.

[0115] In a plan view of the main surface 33, the side surface 46s of the heat transport portion 46 has a stepped shape. Therefore, in a plan view of the main surface 33, the width of the heat transport portion 46 increases as it moves away from the cooler 50. In a plan view of the main surface 33, the distance between the heat transport portion 46 and the circuit components 21, 22, 23 decreases as it moves away from the cooler 50. In a plan view of the main surface 33, the side surface 46s of the heat transport portion 46 approaches the circuit components 21, 22, 23 as it moves away from the cooler 50.

[0116] Specifically, the heat transport section 46 includes heat transport elements 46a, 46b, and 46c. In a plan view of the main surface 33, heat transport element 46a faces circuit component 21 but not circuit components 22 and 23. In a plan view of the main surface 33, heat transport element 46b faces circuit components 21 and 22 but not circuit component 23. In a plan view of the main surface 33, heat transport element 46c faces circuit components 21, 22, and 23.

[0117] In a plan view of the main surface 33, the heat transport element 46c is longer than the heat transport elements 46a and 46b. In a plan view of the main surface 33, the heat transport element 46b is longer than the heat transport element 46a. The distal end face of the heat transport element 46a relative to the cooler 50 may be flush with the end face 31 of the metal base substrate 30. The distal end face of the heat transport element 46b relative to the cooler 50 may be flush with the end face 31 of the metal base substrate 30. The distal end face of the heat transport element 46c relative to the cooler 50 may be flush with the end face 31 of the metal base substrate 30. The proximal end face of the heat transport element 46a relative to the cooler 50 is separated from the end face 32 of the metal base substrate 30. The proximal end face of the heat transport element 46b relative to the cooler 50 is separated from the end face 32 of the metal base substrate 30. The proximal end face of the heat transport element 46c relative to the cooler 50 may be flush with the end face 32 of the metal base substrate 30.

[0118] In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction) (e.g., the x direction), heat transport element 46a is positioned closest to the multiple circuit components 21, 22, 23 among heat transport elements 46a, 46b, and 46c. In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction) (e.g., the x direction), heat transport element 46c is positioned furthest from the multiple circuit components 21, 22, 23 among heat transport elements 46a, 46b, and 46c. In a plan view of the main surface 33, in a direction perpendicular to the direction in which the multiple circuit components 21, 22, 23 are arranged (e.g., the z direction) (e.g., the x direction), heat transport element 46b is positioned between heat transport element 46a and heat transport element 46c. The heat transport element 46b is thermally connected to the heat transport elements 46a and 46c. The heat transport elements 46a, 46b, and 46c are integrated and may be a single component.

[0119] In a plan view of the main surface 33, in the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction), the length of the heat transfer path from the circuit components to the cooler 50 increases as it moves away from the cooler 50. In contrast, the sides 45s and 46s of the heat transport sections 45 and 46 have a stepped shape. In a plan view of the main surface 33, in the direction perpendicular to the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction) (e.g., the x-direction), the distance between the circuit components and at least one of the multiple heat transport sections 45 and 46 (e.g., heat transport section 45 and 46) decreases as it moves away from the cooler 50. Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 decreases.

[0120] The power converter 1h of this embodiment provides the same effects as the power converter 1g of Embodiment 7.

[0121] In the power converter 1h, in a plan view of the first main surface (main surface 33), the side surface (e.g., side surface 45s, 46s) of at least one of the multiple heat transport parts 45, 46 (e.g., heat transport parts 45, 46) has a stepped shape.

[0122] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. The power converter 1h can cool the multiple circuit components 21, 22, and 23 more uniformly. Among the multiple circuit components 21, 22, and 23, the circuit component located further away from the cooler 50 (e.g., circuit component 21) can be a circuit component that generates more heat. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1h becomes easier.

[0123] Embodiment 9. Referring to Figure 24, the power converter 1i according to Embodiment 9 will be described. The power converter 1i of this embodiment has the same configuration as the power converter 1d of Embodiment 4, but differs mainly in the following points.

[0124] As you move away from the cooler 50, the distance between the metal base substrate 30 and the first heat transport member 40 decreases. Therefore, as you move away from the cooler 50, the distance between the multiple circuit components 21, 22, 23 and the first heat transport member 40 decreases.

[0125] Specifically, as you move away from the cooler 50, the distance between the metal base substrate 30 and the first heat transport member 40 in the thickness direction (e.g., the y-direction) of the metal base substrate 30 decreases. The distance between the circuit component 22 and the first heat transport member 40 is smaller than the distance between the circuit component 23 and the first heat transport member 40. The distance between the circuit component 21 and the first heat transport member 40 is smaller than the distance between the circuit component 22 and the first heat transport member 40.

[0126] In a plan view of the main surface 33, in the direction of arrangement of the multiple circuit components 21, 22, 23 (e.g., the z-direction), the length of the heat transfer path from the circuit components to the cooler 50 increases as the distance from the cooler 50 increases. In contrast, in the thickness direction of the metal base substrate 30 (e.g., the y-direction), the distance between the circuit components and the first heat transport member 40 decreases as the distance from the cooler 50 increases. Therefore, the difference between the thermal resistance of the heat transfer path from the circuit components located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 decreases, as does the thermal resistance of the heat transfer path from the circuit components located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50.

[0127] In addition to the effects of the power converter 1d of Embodiment 4, the power converter 1i of this embodiment provides the following effects.

[0128] In the power converter 1i, the distance between the metal base substrate 30 and the first heat transport member 40 decreases as the distance from the cooler 50 increases.

[0129] Therefore, the difference between the thermal resistance of the heat transfer path from a circuit component located further away from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from a circuit component located closer to the cooler 50 (e.g., circuit component 23) to the cooler 50 is reduced. The power converter 1i can cool the multiple circuit components 21, 22, and 23 more uniformly. Among the multiple circuit components 21, 22, and 23, the circuit component located further away from the cooler 50 (e.g., circuit component 21) can be a circuit component that generates more heat. The degree of freedom in arranging the multiple circuit components 21, 22, and 23 is improved. The thermal design of the power converter 1i becomes easier.

[0130] Embodiment 10. Referring to Figure 25, the power converter 1j according to Embodiment 10 will be described. The power converter 1j of this embodiment has the same configuration as the power converter 1d of Embodiment 4, but differs mainly in the following points.

[0131] The power converter 1j further comprises a metal member 70. The metal member 70 includes an end face 71, an end face 72 opposite to end face 71, and a main surface 73. End face 71 is the distal end face of the metal member 70 relative to the cooler 50. End face 71 faces the end face 32 of the metal base substrate 30. End face 72 is the proximal end face of the metal member 70 relative to the cooler 50. End face 72 faces the cooler 50. Each of the end faces 71 and 72 is larger than the end face 32 of the metal base substrate 30. Each of the end faces 71 and 72 may be larger than the end face 42 of the first heat transport member 40. The main surface 73 is connected to the end faces 71 and 72. The main surface 73 is the end face of the metal member 70 in the thickness direction (e.g., the y-direction). The main surface 73 faces the main surface 43 of the first heat transport member 40 and the main surface 63 of the metal support member 60.

[0132] The metal base substrate 30 is thermally connected to the cooler 50 via a metal member 70. The metal member 70 is thermally connected to the metal base substrate 30, the first heat transport member 40, the metal support member 60, and the cooler 50. Specifically, the end face 71 of the metal member 70 is thermally connected to the end face 32 of the metal base substrate 30. The end face 72 of the metal member 70 is thermally connected to the cooler 50. The main surface 73 of the metal member 70 is thermally connected to the main surface 43 of the first heat transport member 40 and the main surface 63 of the metal support member 60.

[0133] The metal member 70 is fixed to the metal base substrate 30, the first heat transport member 40, the metal support member 60, and the cooler 50. For example, the end face 71 of the metal member 70 is fixed to the end face 32 of the metal base substrate 30 by crimping, pressure welding, soldering, brazing, bonding, or welding. The end face 72 of the metal member 70 is fixed to the cooler 50 by crimping, pressure welding, soldering, brazing, bonding, or welding. The main surface 73 of the metal member 70 is fixed to the main surface 43 of the first heat transport member 40 and the main surface 63 of the metal support member 60 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0134] The thermal conductivity of the metal member 70 is equal to or higher than that of the metal plate 36. The metal member 70 is made of a metal such as copper, iron, aluminum, an iron alloy, or an aluminum alloy. The metal member 70 may be made of the same material as the metal support member 60. The metal member 70 has a thermal conductivity of, for example, 1.0 W / (m·K) or more. The metal member 70 may have a thermal conductivity of 10.0 W / (m·K) or more, or 100.0 W / (m·K) or more. The metal member 70 transfers the heat generated by the multiple circuit components 21, 22, and 23 to the cooler 50.

[0135] The metal member 70 may be a rigid member such as a metal block. The cross-sectional area of ​​the metal member 70 may be larger than the cross-sectional area of ​​the metal base substrate 30. The cross-sectional area of ​​the metal member 70 is the cross-sectional area of ​​the metal member 70 in a section perpendicular to the direction in which the heat generated by the multiple circuit components 21, 22, 23 is mainly transferred (for example, the z-direction). The metal member 70 may be integrated with the metal support member 60, or the metal member 70 and the metal support member 60 may be a single member.

[0136] In a modified example of this embodiment, the main surface 73 of the metal member 70 may be connected to at least one of the main surface 43 of the first heat transport member 40 or the main surface 63 of the metal support member 60.

[0137] Referring to Figure 26, in another modified power converter 1k of this embodiment, the metal member 70 is positioned between the metal base substrate 30 and the cooler 50, and also between the metal support member 60 and the cooler 50. The end face 62 of the metal support member 60 may be flush with the end face 32 of the metal base substrate 30. The main face 73 of the metal member 70 may be flush with the main face of the metal support member 60 on the opposite side of the main face 63. The metal support member 60 is thermally connected to the cooler 50 via the metal member 70. Specifically, the end face 71 of the metal member 70 faces the end face 32 of the metal base substrate 30 and the end face 62 of the metal support member 60, and is thermally connected to the end face 32 of the metal base substrate 30 and the end face 62 of the metal support member 60. The metal member 70 is fixed to the metal base substrate 30 and the metal support member 60 by crimping, pressure welding, soldering, brazing, bonding or welding.

[0138] A hole 74 is provided in the metal member 70. The hole 74 may be a through hole extending from end face 71 to end face 72, or it may be a blind hole formed in end face 71 and not reaching end face 72. The first heat transport member 40 includes a projection 76 that protrudes from the end face 32 of the metal base substrate 30 in a plan view of the main surface 33. The projection 76 includes the end face 42. The projection 76 is inserted into the hole 74 and is thermally connected to the metal member 70. The projection 76 is fixed to the metal member 70 by fitting, crimping, pressure welding, soldering, brazing, bonding or welding.

[0139] The metal member 70 may be a single metal part, or it may be formed by combining multiple metal parts.

[0140] In addition to the effects of the power converter 1d of Embodiment 4, the power converters 1j and 1k of this embodiment will be described below.

[0141] The power converters 1j and 1k further include a metal member 70 that is thermally connected to the cooler 50. The first end face (end face 32) is thermally connected to the metal member 70.

[0142] Therefore, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is reduced. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0143] In the power converter 1j,1k, the end face 72 of the metal member 70 facing the cooler 50 is larger than the first end face (end face 32).

[0144] Therefore, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is reduced. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0145] Embodiment 11. Referring to Figure 27, the power converter 1m according to Embodiment 11 will be described. The power converter 1m of this embodiment has the same configuration as the power converter 1j of Embodiment 10, but differs mainly in the following points.

[0146] The first heat transport member 40 includes a heat transport portion 48 and a heat transport portion 49. The heat transport portion 48 includes the main surfaces 43 and 44 of the first heat transport member 40. The heat transport portion 48 includes the end face 41 and the end face 48a of the first heat transport member 40. The end face 41 of the first heat transport member 40 is the distal end face of the heat transport portion 48 relative to the cooler 50. The end face 48a is the proximal end face of the heat transport portion 48 relative to the cooler 50. The end face 48a faces the cooler 50. The heat transport portion 48 includes the end face 42 of the first heat transport member 40. The end face 48a is part of the end face 42 of the first heat transport member 40. The end face 48a of the heat transport portion 48 may be flush with the end face 62 of the metal support member 60 and the end face 72 of the metal member 70.

[0147] The heat transport section 48 is thermally connected to the metal base substrate 30, the metal component 70, the cooler 50, and the metal support member 60. The heat transport section 48 is fixed to the metal base substrate 30, the metal component 70, the cooler 50, and the metal support member 60 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0148] The heat transport portion 49 is connected to the heat transport portion 48. The heat transport portion 49 protrudes from the main surface 43 of the first heat transport member 40 in the thickness direction (e.g., the y-direction) of the metal base substrate 30. The heat transport portion 49 includes an end face 49a. The end face 49a is the proximal end face of the heat transport portion 49 relative to the cooler 50. The end face 49a faces the cooler 50. The heat transport portion 49 includes an end face 42 of the first heat transport member 40. The end face 49a is part of the end face 42 of the first heat transport member 40. The end face 49a of the heat transport portion 49 may be flush with the end face 62 of the metal support member 60 and the end face 72 of the metal member 70. The end face 42 of the first heat transport member 40 is composed of an end face 48a and an end face 49a.

[0149] The heat transport section 49 is thermally connected to the metal member 70 and the cooler 50. The heat transport section 49 is fixed to the metal member 70 and the cooler 50 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0150] Referring to Figure 28, a modified example of this embodiment of the power conversion device 1n will be described. In the power conversion device 1n, the first heat transport member 40 is thermally connected to the cooler 50 via a metal member 70 and a metal support member 60. Parts of the metal member 70 and the metal support member 60 are located between the end face 42 of the first heat transport member 40 and the cooler 50. The end face 42 of the first heat transport member 40 is separated from the cooler 50 by the metal member 70 and the metal support member 60.

[0151] The heat transport section 48 is thermally connected to the metal base substrate 30, the metal member 70, and the metal support member 60. The heat transport section 48 is fixed to the metal base substrate 30, the metal member 70, and the metal support member 60 by crimping, pressure welding, soldering, brazing, bonding, or welding. The heat transport section 48 is thermally connected to the cooler 50 via the metal support member 60. The metal support member 60 is located between the end face 48a of the heat transport section 48 and the cooler 50.

[0152] The heat transport section 49 is thermally connected to the metal member 70. The heat transport section 49 is fixed to the metal member 70 by crimping, fitting, soldering, brazing, bonding, or welding. The metal member 70 is fixed to the cooler 50. The heat transport section 49 is thermally connected to the cooler 50 via the metal member 70. The metal member 70 is located between the end face 49a of the heat transport section 49 and the cooler 50.

[0153] In addition to the effects of the power converter 1j of Embodiment 10, the power converters 1m and 1n of this embodiment will be described below.

[0154] In the power converter 1m,1n, the first heat transport member 40 includes a first heat transport portion (heat transport portion 48) including a second main surface (main surface 43), and a second heat transport portion (heat transport portion 49) protruding from the second main surface. The second heat transport portion includes a second end surface (end surface 42) and is thermally connected to the cooler 50.

[0155] Therefore, the first heat transport member 40 faces the cooler 50 over a larger area. The thermal resistance of the heat transfer path from the multiple circuit components 21, 22, 23 to the cooler 50 is reduced. The multiple circuit components 21, 22, 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0156] The power converter 1m,1n further comprises a metal member 70 which is thermally connected to the cooler 50. The first end face (end face 32) and the second heat transport portion (heat transport portion 49) are thermally connected to the metal member 70.

[0157] Therefore, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is reduced. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0158] Embodiment 12. Referring to Figure 29, the power converter 1p according to Embodiment 12 will be described. The power converter 1p of this embodiment has the same configuration as the power converter 1 of Embodiment 1, but differs mainly in the following points.

[0159] The power conversion device 1p further comprises a second heat transport member 80 and a fixing member 85. The second heat transport member 80, like the first heat transport member 40, transports or diffuses the heat generated by the multiple circuit components 21, 22, and 23 to the cooler 50.

[0160] Specifically, the second heat transport member 80 includes an end face 81, an end face 82 opposite to end face 81, and a main face 83. The end faces 81 and 82 are, for example, the end faces of the second heat transport member 80 in the longitudinal direction (e.g., the z direction). The longitudinal direction (e.g., the z direction) of the second heat transport member 80 is not particularly limited, but may be the direction of gravity. End face 81 is the distal end face of the second heat transport member 80 relative to the cooler 50. End face 82 is the proximal end face of the second heat transport member 80 relative to the cooler 50. End face 82 faces the cooler 50.

[0161] The end face 82 of the second heat transport member 80 is thermally connected to the cooler 50. The end face 82 of the second heat transport member 80 is fixed to the cooler 50 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0162] The main surface 83 is connected to the end surfaces 81 and 82. The main surface 83 is the end surface in the thickness direction of the second heat transport member 80. The main surface 83 faces the multiple circuit components 21, 22, 23 and the main surface 33 of the metal base substrate 30. The main surface 83 of the second heat transport member 80 is thermally connected to the multiple circuit components 21, 22, 23. The main surface 83 of the second heat transport member 80 is fixed to the multiple circuit components 21, 22, 23 by means of pressure welding, soldering, brazing, bonding, or welding.

[0163] The thermal conductivity of the second heat transport member 80 is equal to or higher than the thermal conductivity of the metal plate 36. The second heat transport member 80 is, for example, a heat pipe, a vapor chamber, or a graphite sheet, or a metal plate integrated with any of these. The second heat transport member 80 is formed of a metallic material such as copper, iron, aluminum, an iron alloy or an aluminum alloy, or carbon. The second heat transport member 80 may be formed of the same material as the first heat transport member 40. The second heat transport member 80 has, for example, a thermal conductivity of 1.0 W / (m·K) or more. The second heat transport member 80 may have a thermal conductivity of 10.0 W / (m·K) or more, or a thermal conductivity of 100.0 W / (m·K) or more.

[0164] The second heat transport member 80 is fixed to the metal base substrate 30 using a fixing member 85. The fixing member 85 is, for example, a screw or adhesive. The second heat transport member 80 presses the multiple circuit components 21, 22, and 23 toward the metal base substrate 30. As a result, the vibration resistance of the power converter 1p is improved. Deterioration of the multiple circuit components 21, 22, and 23 can be prevented.

[0165] Referring to Figure 30, a modified example of this embodiment of the power converter 1q will be described. The power converter 1q further comprises a metal member 70, similar to the power converter 1j of Embodiment 10.

[0166] The end face 71 of the metal member 70 faces the end face 82 of the second heat transport member 80. The end face 71 of the metal member 70 may be larger than the end face 82 of the second heat transport member 80. The end face 72 of the metal member 70 faces the cooler 50. The end face 72 of the metal member 70 may be larger than the end face 82 of the second heat transport member 80. The main surface 73 of the metal member 70 faces the main surface 43 of the first heat transport member 40.

[0167] The metal member 70 is thermally connected to the second heat transport member 80, the metal base substrate 30, the first heat transport member 40, and the cooler 50. The second heat transport member 80 is thermally connected to the cooler 50 via the metal member 70. The end face 82 of the second heat transport member 80 is thermally connected to the end face 71 of the metal member 70. The end face 72 of the metal member 70 is thermally connected to the cooler 50.

[0168] The metal member 70 is fixed to the second heat transport member 80, the metal base substrate 30, the first heat transport member 40, and the cooler 50. For example, the end face 71 of the metal member 70 is fixed to the end face 82 of the second heat transport member 80 and the end face 32 of the metal base substrate 30 by crimping, pressure welding, soldering, brazing, bonding, or welding. The end face 72 of the metal member 70 is fixed to the cooler 50 by crimping, pressure welding, soldering, brazing, bonding, or welding. The main surface 73 of the metal member 70 is fixed to the main surface 43 of the first heat transport member 40 by crimping, pressure welding, soldering, brazing, bonding, or welding.

[0169] In addition to the effects of the power converter 1 of Embodiment 1, the power converters 1p and 1q of this embodiment will be described below.

[0170] The power converters 1p and 1q further comprise a second heat transport member 80 including a fifth main surface (main surface 83) and a fifth end surface (end surface 82) connected to the fifth main surface. The fifth main surface is thermally connected to a plurality of circuit components 21, 22, and 23. The fifth end surface is thermally connected to the cooler 50.

[0171] The heat generated by the multiple circuit components 21, 22, and 23 is transferred to the cooler 50 not only by the metal base substrate 30 and the first heat transport member 40, but also by the second heat transport member 80. As a result, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is reduced. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0172] The power converter 1q further comprises a metal member 70 which is thermally connected to the cooler 50. The first end face (end face 32) and the fifth end face (end face 82) are thermally connected to the metal member 70.

[0173] Therefore, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is reduced. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0174] Embodiment 13. The power converter 1r according to Embodiment 13 will be described with reference to Figures 31 to 33. The power converter 1r of this embodiment has the same configuration as the power converter 1 of Embodiment 1, but differs mainly in the following points.

[0175] The cooler 50 is provided with a hole 53. The hole 53 may be a through hole formed on the surface of the cooler 50 facing the end face 32, or it may be a blind hole formed on the surface of the cooler 50 facing the end face 32. The cross-sectional shape of the hole 53 (the shape of the hole 53 on the end face 32) may be, for example, a circle, an ellipse, or a rectangle. The first heat transport member 40 includes a projection 76 that protrudes from the end face 32 of the metal base substrate 30 in a plan view of the main surface 33. The projection 76 includes the end face 42. If the hole 53 is a through hole, the end face 42 may protrude from the cooler 50. The projection 76 is inserted into the hole 53 and is thermally connected to the cooler 50. The projection 76 is fixed to the cooler 50 by fitting, crimping, pressure welding, soldering, brazing, bonding, or welding.

[0176] The central axis 52c of the refrigerant flow path (e.g., cooling pipe 52) intersects the insertion direction (z-direction) of the projection 76 into the hole 53. The central axis 52c may also be perpendicular to the insertion direction (z-direction) of the projection 76 into the hole 53. As shown in Figure 33, in a plan view from the insertion direction (z-direction) of the projection 76 into the hole 53, the refrigerant flow path is offset from the projection 76 in the thickness direction (e.g., y-direction) of the metal base substrate 30.

[0177] As shown in Figure 31, in a plan view of the main surface 33, at least a portion of the refrigerant flow path (e.g., cooling pipe 52) may overlap with the projection 76 of the first heat transport member 40. In a plan view of the main surface 33, the first heat transport member 40 may extend with respect to the central axis 52c of the refrigerant flow path to the side opposite to the end face 41. In the insertion direction (z-direction) of the projection 76 into the hole 53, the portion of the refrigerant flow path (e.g., cooling pipe 52) provided on the heat sink 51 may be positioned between the end face 42 and the end face 32.

[0178] Referring to Figures 34 to 36, in the power converter 1s according to the first modified example of this embodiment, the first heat transport member 40 may be divided into a plurality of heat transport portions 45, 46, and the cooler 50 may be provided with a plurality of holes 53 into which the plurality of heat transport portions 45, 46 are inserted. The power converter 1s has the same configuration as the power converter 1d of Embodiment 4, but differs mainly in the following points.

[0179] The cooler 50 is provided with a plurality of holes 53. The plurality of holes 53 may be through holes formed on the surface of the cooler 50 facing the end face 32, or they may be blind holes formed on the surface of the cooler 50 facing the end face 32, or they may be a combination of through holes and blind holes. The cross-sectional shapes of the plurality of holes 53 may be different from each other.

[0180] The first heat transport member 40 includes a projection 76 that protrudes from the end face 32 of the metal base substrate 30 in a plan view of the main surface 33. The projection 76 includes the end face 42. Specifically, the heat transport portion 45 includes a projection 45p that protrudes from the end face 32 of the metal base substrate 30 in a plan view of the main surface 33. The heat transport portion 46 includes a projection 46p that protrudes from the end face 32 of the metal base substrate 30 in a plan view of the main surface 33. The projection 76 includes the projection 45p and the projection 46p. The projection 45p and projection 46p include the end face 42. The projection 45p and projection 46p are inserted into a plurality of holes 53 and are thermally connected to the cooler 50. The projection 45p and projection 46p are fixed to the cooler 50 by fitting, crimping, pressure welding, soldering, brazing, bonding or welding.

[0181] As shown in Figure 34, in a plan view of the main surface 33, at least a portion of the refrigerant flow path (cooling pipe 52) may overlap with the protruding portions 45p and 46p. In a plan view of the main surface 33, the protruding portions 45p and 46p may extend to the side opposite to the end face 41 with respect to the central axis 52c of the refrigerant flow path (e.g., cooling pipe 52) of the cooler. In the insertion direction (z-direction) of the multiple protruding portions 45p and 46p into the multiple holes 53, the portion of the refrigerant flow path (e.g., cooling pipe 52) provided in the heat sink 51 may be positioned between the end face 42 and the end face 32.

[0182] Referring to Figures 37 to 39, the power converter 1t according to the second modified example of this embodiment is configured similarly to the power converter 1r of this embodiment, but instead of the hole 53 (see Figures 31 to 33), a recess 54 is provided in the cooler 50. The recess 54 is formed on the surface of the cooler 50 facing the end face 32. The recess 54 may or may not penetrate the cooler 50. The projection 76 is inserted into the recess 54 and is thermally connected to the cooler 50. The projection 76 is fixed to the cooler 50 by fitting, crimping, pressure welding, soldering, brazing, bonding or welding. The central axis 52c of the refrigerant flow path (e.g., cooling pipe 52) intersects the insertion direction (z direction) of the projection 76 into the recess 54. The central axis 52c may be perpendicular to the insertion direction (z direction) of the projection 76 into the recess 54. As shown in Figure 36, in a plan view from the insertion direction (z-direction) of the projection 76 into the recess 54, the flow path of the refrigerant is offset from the projection 76 in the thickness direction (e.g., y-direction) of the metal base substrate 30.

[0183] Referring to Figures 40 to 42, the power converter 1u according to the third modified example of this embodiment is configured similarly to the power converter 1s of the first modified example of this embodiment, but instead of a plurality of holes 53 (see Figures 34 to 36), a plurality of recesses 54 are provided in the cooler 50. The plurality of recesses 54 are formed on the surface of the cooler 50 facing the end face 32. The plurality of recesses 54 may or may not penetrate the cooler 50. A portion of the plurality of recesses 54 may penetrate the cooler 50, while the remainder of the plurality of recesses 54 may not penetrate the cooler 50. The protruding portions 45p and 46p are inserted into the plurality of recesses 54 and are thermally connected to the cooler 50. The protruding portions 45p and 46p are fixed to the cooler 50 by fitting, crimping, pressure welding, soldering, brazing, bonding or welding.

[0184] Referring to Figures 43 to 45, the power converter 1v according to the fourth modification of this embodiment is configured similarly to the power converter 1t of the second modification of this embodiment, but further includes a fixing plate 87. The fixing plate 87 is fixed to the heat sink 51 by crimping, pressure welding, soldering, brazing, bonding, or welding. The fixing plate 87 may also be fixed to the protrusion 76 of the first heat transport member 40 by crimping, pressure welding, soldering, brazing, bonding, or welding. The protrusion 76 is sandwiched between the heat sink 51 and the fixing plate 87. The fixing plate 87 prevents the protrusion 76 from coming out of the recess 54. The fixing plate 87 is formed of, for example, metal or resin. By forming the fixing plate 87 of metal, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, 23 to the cooler 50 is further reduced.

[0185] Referring to Figures 46 to 48, the power converter 1w according to the fifth modification of this embodiment is configured similarly to the power converter 1u of the third modification of this embodiment, but further includes a fixing plate 87. The fixing plate 87 is fixed to the heat sink 51 by crimping, pressure welding, soldering, brazing, bonding, or welding. The fixing plate 87 may also be fixed to the protruding portions 45p and 46p of the heat transport portions 45 and 46 by crimping, pressure welding, soldering, brazing, bonding, or welding. The protruding portions 45p and 46p are sandwiched between the heat sink 51 and the fixing plate 87. The fixing plate 87 prevents the protruding portions 45p and 46p from coming out of the recess 54. The fixing plate 87 is formed of, for example, metal or resin. By forming the fixing plate 87 of metal, the thermal resistance of the heat transfer path from the multiple circuit components 21, 22, and 23 to the cooler 50 is further reduced.

[0186] In a sixth modification of this embodiment, the multiple protruding portions 45p, 46p of the heat transport portions 45, 46 may be inserted into at least one hole 53 and at least one recess 54.

[0187] The power converters 1r, 1s, 1t, 1u, 1v, and 1w of this embodiment provide the same effects as the power converter 1 of Embodiment 1.

[0188] The power converters 1r, 1s, 1t, 1u, 1v, and 1w of this embodiment include a plurality of circuit components 21, 22, and 23, a metal base substrate 30 including a metal plate 36, a heat transport member (first heat transport member 40), and a cooler 50. The metal base substrate 30 includes a first main surface (main surface 33) on which the plurality of circuit components 21, 22, and 23 are mounted, a second main surface (main surface 34) opposite to the first main surface, and a first end surface (end surface 32) connected to the first and second main surfaces. The metal plate 36 includes a second main surface. The first end surface faces the cooler 50 and is thermally connected to the cooler 50. The thermal conductivity of the heat transport member is greater than or equal to the thermal conductivity of the metal plate 36. The heat transport member faces the second main surface and is thermally connected to the second main surface. In a plan view of the first main surface, the heat transport member includes a projection 76 that protrudes from the first end face. The cooler 50 is provided with a hole 53 or a recess 54. The projection 76 of the heat transport member is inserted into the hole 53 or recess 54 and is thermally connected to the cooler 50.

[0189] The cooler 50 is thermally connected to the first end face (end face 32) of the metal base substrate 30 and the protrusion 76 of the heat transport member. Therefore, the heat generated by the multiple circuit components 21, 22, and 23 is transferred to the cooler 50 by both the metal base substrate 30 and the heat transport member (first heat transport member 40) and concentrated in the cooler 50. Even if the number of multiple circuit components 21, 22, and 23 increases and the size of the metal base substrate 30 increases, the multiple circuit components 21, 22, and 23 can be cooled without increasing the size of the cooler 50.

[0190] The power converters 1r, 1s, 1t, 1u, 1v, and 1w are equipped with a heat transport member (first heat transport member 40) in addition to the metal base substrate 30. Therefore, the difference between the thermal resistance of the heat transfer path from the circuit component 21, 22, and 23 located further from the cooler 50 (e.g., circuit component 21) to the cooler 50 and the thermal resistance of the heat transfer path from the circuit component 23 located closer to the cooler 50 to the cooler 50 is reduced. The power converters 1r, 1s, 1t, 1u, 1v, and 1w can cool the circuit components 21, 22, and 23 more uniformly. Circuit components that generate more heat can be used as the circuit component located further from the cooler 50 (e.g., circuit component 21) among the circuit components 21, 22, and 23. The degree of freedom in the arrangement of the circuit components 21, 22, and 23 is improved. Thermal design for power converters 1r, 1s, 1t, 1u, 1v, and 1w becomes easier.

[0191] The protruding portion 76 of the heat transport member (first heat transport member 40) is inserted into the hole 53 or recess 54. As a result, the vibration resistance of the power conversion devices 1r, 1s, 1t, 1u, 1v, and 1w is improved.

[0192] In the power converters 1r, 1s, 1t, 1u, 1v, and 1w of this embodiment, a coolant flow path (cooling pipe 52) is formed in the cooler 50.

[0193] The heat generated by the multiple circuit components 21, 22, and 23 is carried away to the outside of the power converter 1 by a coolant. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0194] In the power conversion devices 1r, 1s, 1t, 1u, 1v, 1w of this embodiment, in a plan view of the first main surface (main surface 33), at least a portion of the refrigerant flow path (cooling pipe 52) overlaps with the protrusion 76 of the heat transport member (first heat transport member 40).

[0195] Therefore, the distance between the refrigerant flow path (cooling pipe 52) and the heat transport member (first heat transport member 40) is reduced. Heat generated in the multiple circuit components 21, 22, and 23 can be transferred to the refrigerant flow path with lower thermal resistance. The multiple circuit components 21, 22, and 23 are efficiently cooled by the cooler 50. The cooler 50 can be made smaller.

[0196] The various aspects of this disclosure are summarized below as an appendix. (Note 1) Multiple circuit components, A metal base substrate including a metal plate, First heat transport member and Equipped with a cooler, The metal base substrate includes a first main surface on which the plurality of circuit components are mounted, and a first end surface connected to the first main surface. The thermal conductivity of the first heat transport member is greater than or equal to the thermal conductivity of the metal plate. The first heat transport member includes a second main surface and a second end surface connected to the second main surface and facing the cooler. The first end face and the second end face are thermally connected to the cooler. The second main surface is thermally connected to the metal base substrate, and is a power conversion device. (Note 2) The metal base substrate includes a third end face opposite to the first end face, In a plan view of the first main surface, the first heat transport member extends from the first end face to the third end face, as described in Appendix 1, for the power conversion device. (Note 3) The power conversion device according to Appendix 1, wherein the distance between the metal base substrate and the first heat transport member decreases as it moves away from the cooler. (Note 4) The power conversion device according to Appendix 1, wherein the contact area between the metal base substrate and the first heat transport member increases as it moves away from the cooler. (Note 5) The first heat transport member further comprises a metal support member, The metal base substrate includes a third main surface opposite to the first main surface, and the third main surface is connected to the first end surface. The metal support member includes a fourth main surface thermally connected to the third main surface and a fourth end surface connected to the fourth main surface. The fourth end face is thermally connected to the cooler, as described in Appendix 1, for the power conversion device. (Note 6) In a plan view of the first main surface, the plurality of circuit components overlap the first heat transport member, as described in Appendix 5, for the power conversion device. (Note 7) The first heat transport member includes a plurality of heat transport portions, Each of the aforementioned heat transport components is thermally connected to the metal base substrate and the cooler. The power conversion device according to Appendix 5, wherein the distance between the plurality of circuit components and at least one of the plurality of heat transport parts decreases as the distance from the cooler increases. (Note 8) The power conversion device according to Appendix 7, wherein, in a plan view of the first main surface, as it moves away from the cooler, at least one side of the plurality of heat transport portions facing the plurality of circuit components approaches the plurality of circuit components. (Note 9) In the plan view of the first main surface, the plurality of circuit components are arranged in a direction away from the cooler. The power conversion device according to Appendix 8, wherein, in the plan view of the first main surface, at least one of the plurality of heat transport portions is inclined with respect to the direction in which the plurality of circuit components are arranged. (Note 10) The power conversion device according to Appendix 8, wherein, in the plan view of the first main surface, the width of at least one of the plurality of heat transport portions increases as it moves away from the cooler. (Note 11) In the plan view of the first main surface, the plurality of circuit components are arranged in a direction away from the cooler. The power conversion device according to Appendix 10, wherein, in the plan view of the first main surface, at least one of the sides of the plurality of heat transport portions is inclined with respect to the direction in which the plurality of circuit components are arranged. (Note 12) The power conversion device according to Appendix 10, wherein, in the plan view of the first main surface, at least one of the multiple heat transport portions has a stepped shape. (Note 13) The power conversion device according to Appendix 7, wherein the distance between the metal base substrate and the first heat transport member decreases as it moves away from the cooler. (Note 14) The cooler further comprises a metal member that is thermally connected to the cooler, The power conversion device described in Appendix 1, wherein the first end face is thermally connected to the metal member. (Note 15) The power conversion device according to Appendix 14, wherein the end face of the metal member facing the cooler is larger than the first end face. (Note 16) The first heat transport member includes a first heat transport portion including the second main surface and a second heat transport portion protruding from the second main surface. The power conversion device according to Appendix 1, wherein the second heat transport portion includes the second end face and is thermally connected to the cooler. (Note 17) The cooler further comprises a metal member that is thermally connected to the cooler, The power conversion device as described in Appendix 16, wherein the first end face and the second heat transport portion are thermally connected to the metal member. (Note 18) The second heat transport member further includes a fifth main surface and a fifth end surface connected to the fifth main surface, The fifth main surface is thermally connected to the plurality of circuit components, The fifth end face is thermally connected to the cooler, as described in Appendix 1, for the power conversion device. (Note 19) The cooler further comprises a metal member that is thermally connected to the cooler, The power conversion device according to Appendix 18, wherein the first end face and the fifth end face are thermally connected to the metal member. (Note 20) Multiple circuit components, A metal base substrate including a metal plate, Heat transport member and Equipped with a cooler, The metal base substrate includes a first main surface on which the plurality of circuit components are mounted, a second main surface opposite to the first main surface, and a first end surface connected to the first main surface and the second main surface, and the metal plate includes the second main surface. The first end face faces the cooler and is thermally connected to the cooler. The thermal conductivity of the heat transport member is greater than or equal to the thermal conductivity of the metal plate. The heat transport member is facing the second main surface and is thermally connected to the second main surface. In a plan view of the first main surface, the heat transport member includes a projection that protrudes from the first end face, The cooler is provided with holes or recesses, A power conversion device in which the protruding portion of the heat transport member is inserted into the hole or the recess and is thermally connected to the cooler. (Note 21) The power conversion device described in Appendix 20, wherein a coolant flow path is formed in the cooler. (Note 22) The power conversion device according to Appendix 21, wherein, in the plan view of the first main surface, at least a portion of the flow path overlaps the protruding portion of the heat transport member.

[0197] Embodiments 1-13 and their variations disclosed herein should be considered in all respects as illustrative and not restrictive. To the extent that they do not contradict each other, at least two of Embodiments 1-13 and their variations disclosed herein can be combined. The scope of this disclosure is indicated by the claims rather than the foregoing description and is intended to include all modifications within the meaning and scope of the claims equivalents. [Explanation of Symbols]

[0198] 1,1b,1c,1d,1e,1f,1g,1h,1i,1j,1k,1m,1n,1p,1q,1r,1s,1t,1u,1v,1w Power converter, 2 Inverter circuit, 3 Transformer circuit, 4 Rectifier circuit, 5 Smoothing circuit, 6 Input terminal, 7 Output terminal, 8 Input capacitor, 9a,9b,9c,9d Switching element, 10 Control circuit, 11 Transformer, 11a Primary winding, 11b Secondary winding, 12a,12b Rectifier element, 13 Smoothing reactor, 14 Smoothing capacitor, 21,22,23,24,25,26 Circuit components, 30 Metal base substrate, 31,32 Edge face, 33,34 Main face, 36 Metal plate, 37 Insulating layer, 38 Circuit pattern, 39 Conductive bonding member, 40 First heat transport member, 41, 42 end faces, 43, 44 main faces, 45, 46, 47 heat transport portion, 45a, 45b, 45c, 46a, 46b, 46c heat transport element, 45p, 46p protruding portion, 45s, 46s side, 48, 49 heat transport portion, 48a, 49a end face, 50 cooler, 51 heat sink, 52 cooling pipe, 52c central axis, 53 hole, 54 recess, 55 air layer, 60 metal support member, 61, 62 end faces, 63 main face, 65, 66, 67 groove, 70 metal member, 71, 72 end faces, 73 main face, 74 hole, 76 protruding portion, 80 second heat transport member, 81, 82 end faces, 83 main face, 85 fixing member, 87 Fixed plate.

Claims

1. Multiple circuit components, A metal base substrate including a metal plate, First heat transport member and Equipped with a cooler, The metal base substrate includes a first main surface on which the plurality of circuit components are mounted, and a first end surface connected to the first main surface. The thermal conductivity of the first heat transport member is greater than or equal to the thermal conductivity of the metal plate. The first end face is thermally connected to the cooler, The first heat transport member is thermally connected to the cooler and the metal base substrate in a power conversion device.

2. The first heat transport member includes a second main surface and a second end surface connected to the second main surface and facing the cooler, The power conversion device according to claim 1, wherein the second end face is thermally connected to the cooler.

3. The metal base substrate includes a third end face opposite to the first end face, The power conversion device according to claim 1, wherein, in a plan view of the first main surface, the first heat transport member extends from the first end face to the third end face.

4. The power conversion device according to claim 1, wherein the distance between the metal base substrate and the first heat transport member decreases as it moves away from the cooler.

5. The power conversion device according to claim 1, wherein the contact area between the metal base substrate and the first heat transport member increases as it moves away from the cooler.

6. The first heat transport member is further supported by a metal support member, The metal base substrate includes a third main surface opposite to the first main surface, and the third main surface is connected to the first end surface. The metal support member includes a fourth main surface thermally connected to the third main surface and a fourth end surface connected to the fourth main surface. The power conversion device according to claim 1, wherein the fourth end face is thermally connected to the cooler.

7. The power conversion device according to claim 6, wherein, in a plan view of the first main surface, the plurality of circuit components overlap the first heat transport member.

8. The first heat transport member includes a plurality of heat transport portions, Each of the aforementioned heat transport components is thermally connected to the metal base substrate and the cooler. The power conversion device according to claim 6, wherein the distance between the plurality of circuit components and at least one of the plurality of heat transport parts decreases as the distance from the cooler increases.

9. The power conversion device according to claim 8, wherein, in a plan view of the first main surface, as it moves away from the cooler, at least one side of the plurality of heat transport portions facing the plurality of circuit components approaches the plurality of circuit components.

10. In the plan view of the first main surface, the plurality of circuit components are arranged in a direction away from the cooler. The power conversion device according to claim 9, wherein in the plan view of the first main surface, at least one of the plurality of heat transport portions is inclined with respect to the direction in which the plurality of circuit components are arranged.

11. The power conversion device according to claim 9, wherein, in the plan view of the first main surface, the width of at least one of the plurality of heat transport portions increases as it moves away from the cooler.

12. In the plan view of the first main surface, the plurality of circuit components are arranged in a direction away from the cooler. The power conversion device according to claim 11, wherein in the plan view of the first main surface, at least one of the sides of the plurality of heat transport portions is inclined with respect to the direction in which the plurality of circuit components are arranged.

13. The power conversion device according to claim 11, wherein in the plan view of the first main surface, at least one of the multiple heat transport portions has a stepped shape.

14. The power conversion device according to claim 8, wherein the distance between the metal base substrate and the first heat transport member decreases as the distance from the cooler increases.

15. The cooler further comprises a metal member that is thermally connected to the cooler, The power conversion device according to claim 1, wherein the first end face is thermally connected to the metal member.

16. The power conversion device according to claim 15, wherein the end face of the metal member facing the cooler is larger than the first end face.

17. The first heat transport member includes a first heat transport portion including the second main surface and a second heat transport portion protruding from the second main surface. The power conversion device according to claim 2, wherein the second heat transport portion includes the second end face and is thermally connected to the cooler.

18. The cooler further comprises a metal member that is thermally connected to the cooler, The power conversion device according to claim 17, wherein the first end face and the second heat transport portion are thermally connected to the metal member.

19. The second heat transport member further includes a fifth main surface and a fifth end surface connected to the fifth main surface, The fifth main surface is thermally connected to the plurality of circuit components, The power conversion device according to claim 1, wherein the fifth end face is thermally connected to the cooler.

20. The cooler further comprises a metal member that is thermally connected to the cooler, The power conversion device according to claim 19, wherein the first end face and the fifth end face are thermally connected to the metal member.

21. The power conversion device according to any one of claims 1 to 20, wherein a coolant flow path is formed in the cooler.

22. Multiple circuit components, A metal base substrate including a metal plate, Heat transport member and Equipped with a cooler, The metal base substrate includes a first main surface on which the plurality of circuit components are mounted, a second main surface opposite to the first main surface, and a first end surface connected to the first main surface and the second main surface. The first end face faces the cooler and is thermally connected to the cooler. The thermal conductivity of the heat transport member is greater than or equal to the thermal conductivity of the metal plate. The heat transport member is facing the second main surface and is thermally connected to the second main surface. In a plan view of the first main surface, the heat transport member includes a projection that protrudes from the first end face, The cooler is provided with holes or recesses, A power conversion device in which the protruding portion of the heat transport member is inserted into the hole or the recess and is thermally connected to the cooler.

23. The power conversion device according to claim 22, wherein a coolant flow path is formed in the cooler.

24. The power conversion device according to claim 23, wherein in the plan view of the first main surface, at least a portion of the flow path overlaps the protruding portion of the heat transport member.

25. The power conversion device according to any one of claims 22 to 24, wherein the metal plate includes the second main surface.

Images