Power conversion device and method for manufacturing the same

Abstract

The power conversion device (100) includes electronic components, a first printed circuit board (31), a first cooling body (51), a second printed circuit board (32), a second cooling body (52), a third printed circuit board (33), and a third cooling body (53). The second cooling body (52) extends in a direction from the second main surface (S2) of the first printed circuit board (31) toward the first main surface (S1). The third cooling body (53) extends in a direction from the second main surface (S2) of the first printed circuit board (31) toward the first main surface (S1).

Description

Technical Field

[0001] The present disclosure relates to a power conversion device and a method for manufacturing the power conversion device. Background Art

[0002] Generally, electronic components such as switching elements, rectifying elements, and magnetic components are included in a power conversion device. These electronic components generate heat as the power conversion device operates. The heat generated in these electronic components is transferred to a cooling body through a heat dissipation path and dissipated from the cooling body. In this way, the temperatures of these electronic components are suppressed below the allowable temperatures of the respective electronic components.

[0003] In recent years, as the demand for miniaturization and high output of power conversion devices has increased, the amount of heat generated by the electronic components mounted on the power conversion device has increased. Therefore, there has been a strong demand for improving the heat dissipation performance of the power conversion device.

[0004] As an example of a power conversion device, a motor drive device for an automobile is described in Japanese Patent No. 4231626 (Patent Document 1). In the motor drive device for an automobile described in this publication, a power conversion element, which is a high heat generating component among the electronic components housed in a housing, is arranged on the bottom surface of the housing. The bottom surface of the housing on which the power conversion element is arranged is integrated with a cooling body. In addition, a printed circuit board on which a control element is mounted is fixed to a plate-like substrate mounting portion formed inside the housing. The heat generated in the control element is transferred to the housing via the plate-like substrate mounting portion.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Patent No. 4231626 Summary of the Invention

[0008] Problems to be Solved by the Invention

[0009] In the motor drive device for an automobile described in the above publication, a power conversion element, which is a high heat generating component, is arranged on the bottom surface of the housing. Therefore, when the number of high heat generating components increases due to an increase in the output of the power conversion device, in order to arrange these high heat generating components, it is necessary to increase the area of the bottom surface of the housing. As a result, the power conversion device becomes large-sized. In addition, in the motor drive device for an automobile described in the above publication, the heat generated in the control element is transferred to the housing via the plate-like substrate fixing portion. Therefore, the heat dissipation path becomes long. As a result, the heat dissipation performance deteriorates.

[0010] The present disclosure has been made in view of the above problems, and an object thereof is to provide a power conversion device and a method for manufacturing the power conversion device that can suppress an increase in the bottom area of the power conversion device and can improve the heat dissipation performance.

[0011] Technical solution for solving the problem

[0012] The power conversion device of the present disclosure includes electronic components, a first substrate, a first cooling body, a second substrate, a second cooling body, a third substrate, and a third cooling body. The electronic components include a first component, a second component, and a third component. The first substrate has a first main surface on which the first component of the electronic components is mounted and a second main surface facing the first main surface. The first cooling body is thermally connected to the second main surface of the first substrate. The second substrate has a third main surface on which the second component of the electronic components is mounted and a fourth main surface facing the third main surface. The second cooling body is thermally connected to the fourth main surface of the second substrate. The third substrate has a fifth main surface on which the third component of the electronic components is mounted and a sixth main surface facing the fifth main surface. The third cooling body is thermally connected to the sixth main surface of the third substrate. The second cooling body extends in a direction from the second main surface of the first substrate toward the first main surface. The third cooling body extends in a direction from the second main surface of the first substrate toward the first main surface.

[0013] Effects of the invention

[0014] In the power conversion device according to the present disclosure, the electronic components are mounted not only on the first substrate but also on the second substrate and the third substrate. Therefore, even when the number of electronic components, which are high heat-generating components, increases, it is possible to suppress the enlargement of the first cooling body by mounting the electronic components on the second substrate and the third substrate. Therefore, it is possible to suppress the enlargement of the bottom area of the power conversion device. In addition, by mounting the electronic components on the second substrate and the third substrate, it is possible to shorten the heat dissipation path through which the heat generated in the electronic components mounted on the second substrate is transferred to the second cooling body, and it is possible to shorten the heat dissipation path through which the heat generated in the electronic components mounted on the third substrate is transferred to the third cooling body. Therefore, the heat dissipation performance can be improved. Description of the drawings

[0015] Figure 1 is a circuit diagram of the power conversion device of Embodiment 1.

[0016] Figure 2 is a perspective view schematically showing the structure of the power conversion device of Embodiment 1.

[0017] Figure 3 is a perspective view schematically showing the structure of the first printed circuit board module of the power conversion device of Embodiment 1.

[0018] Figure 4 is a perspective view schematically showing the structure of the second printed circuit board module of the power conversion device of Embodiment 1.

[0019] Figure 5 is a perspective view schematically showing the structure of the third printed circuit board module of the power conversion device of Embodiment 1.

[0020] Figure 6 is a cross-sectional view taken along line VI-VI of Figure 4 .

[0021] Figure 7 is a cross-sectional view corresponding to Figure 6 of Modification 1 of the power conversion device of Embodiment 1.

[0022] Figure 8 is a cross-sectional view taken along line VIII-VIII of Figure 5 .

[0023] Figure 9 is a cross-sectional view corresponding to Figure 8 of Modification 2 of the power conversion device of Embodiment 1.

[0024] Figure 10 is a flowchart showing the manufacturing method of the power conversion device of Embodiment 1.

[0025] Figure 11 is a perspective view for explaining the electrical connection between the printed circuit board modules of the power conversion device of Embodiment 1.

[0026] Figure 12 is a perspective view schematically showing the structure of Modification 3 of the power conversion device of Embodiment 1.

[0027] Figure 13 is a perspective view schematically showing the structure of Modification 4 of the power conversion device of Embodiment 1.

[0028] Figure 14 is a perspective view schematically showing the structure of the power conversion device of Embodiment 2.

[0029] Figure 15 is a perspective view schematically showing the structure of a modification of the power conversion device of Embodiment 2.

[0030] Figure 16 is a perspective view schematically showing the structure of the power conversion device of Embodiment 3.

[0031] Figure 17 is a perspective view schematically showing the structure of the first printed circuit board module of the power conversion device of Embodiment 3.

[0032] Figure 18 is a perspective view schematically showing the structure of the second printed circuit board module of the power conversion device of Embodiment 3.

[0033] Figure 19 is a perspective view schematically showing the structure of the third printed circuit board module of the power conversion device of Embodiment 3.

[0034] Figure 20 is a perspective view schematically showing the structure of the fourth printed circuit board module of the power conversion device according to Embodiment 3.

[0035] Figure 21 is a perspective view schematically showing the structure of the fifth printed circuit board module of the power conversion device according to Embodiment 3.

[0036] Figure 22 is a perspective view schematically showing the structure of Modification 1 of the power conversion device according to Embodiment 3.

[0037] Figure 23 is a perspective view schematically showing the structure of the first printed circuit board module of Modification 1 of the power conversion device according to Embodiment 3.

[0038] Figure 24 is a perspective view schematically showing the structure of the second printed circuit board module of Modification 1 of the power conversion device according to Embodiment 3.

[0039] Figure 25 is a perspective view schematically showing the structure of the third printed circuit board module of Modification 1 of the power conversion device according to Embodiment 3.

[0040] Figure 26 is a perspective view schematically showing the structure of the fourth printed circuit board module of Modification 1 of the power conversion device according to Embodiment 3.

[0041] Figure 27 is a perspective view schematically showing the structure of the fifth printed circuit board module of Modification 1 of the power conversion device according to Embodiment 3.

[0042] Figure 28 is a perspective view schematically showing the structure of the power conversion device according to Embodiment 4.

[0043] Figure 29 is a perspective view schematically showing the structure of the power conversion device according to Embodiment 5.

[0044] Figure 30 is a perspective view schematically showing the structure of Modification 5 of the power conversion device according to Embodiment 1.

[0045] Figure 31 is a perspective view schematically showing the structure of Modification 2 of the power conversion device according to Embodiment 3.

[0046] Figure 32 is a circuit diagram of Modification 6 of the power conversion device according to Embodiment 1.

[0047] Figure 33It is a perspective view schematically showing the structure of the power conversion device according to Embodiment 6.

[0048] Figure 34 It is a circuit diagram of the power conversion device according to Embodiment 6. Detailed Embodiment

[0049] Hereinafter, the embodiments will be described based on the drawings. In addition, hereinafter, the same or corresponding parts will be denoted by the same reference numerals, and repeated descriptions will be omitted.

[0050] Embodiment 1.

[0051] Figure 1 It is an example of a circuit diagram of the power conversion device according to Embodiment 1. Figure 1 The power conversion device shown in the circuit diagram is, for example, a DC-DC converter mounted on an electric vehicle that converts an input voltage of a lithium-ion battery of 100V to 300V DC into a voltage of 12 to 15V DC and outputs it to charge a lead-acid battery. Figure 1 The power conversion device shown in the circuit diagram includes an input capacitor 1, an inverter circuit section 11 composed of four switching elements 2a, 2b, 2c, 2d, a transformer section 12 composed of transformers 3 and 4, a rectifier circuit section 13 composed of eight rectifying elements 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, a smoothing circuit section 14 composed of reactors 6, 7 and a smoothing capacitor 8, an input terminal 9, an output terminal 10, and a control circuit section 15. In addition, Figure 1 Each of the electronic components shown by circuit symbols in can be a series structure or a parallel structure with any number.

[0052] Each of the switching elements 2a, 2b, 2c, 2d is a power semiconductor element such as a transistor, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), or an IGBT (Insulated Gate Bipolar Transistor). The rectifying element 5 is a power semiconductor element such as a diode, a MOSFET, or a thyristor.

[0053] Figure 1The power conversion device shown in the circuit diagram converts the DC voltage input from the input terminal 9 into an AC voltage by performing switching control on the inverter circuit section 11 using the control circuit section 15. The voltage conversion section 12 converts the AC voltage converted by the inverter circuit section 11 into an arbitrary voltage according to the turns ratio of the transformers 3 and 4. In addition, the transformers 3 and 4 electrically insulate the input terminal 9 and the output terminal 10. The rectifier circuit section 13 converts the AC voltage supplied from the transformers 3 and 4 back into a DC voltage. The smoothing circuit section 14 smoothes the DC voltage converted by the rectifier circuit section 13 and stabilizes the output voltage.

[0054] In the power conversion device configured in this way Figure 1 shown in the circuit diagram, the four switching elements 2a, 2b, 2c, 2d, the transformers 3, 4, the eight rectifying elements 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, and the reactors 6, 7 become high heat generating components. It is necessary to dissipate the heat generated in these high heat generating components and keep the temperature of the high heat generating components below the allowable temperature of each component. The allowable temperature of each component is, for example, 100°C or higher and 120°C or lower.

[0055] In addition, since a relatively large current flows through the wiring that electrically connects these high heat generating components, Joule heat is generated in the wiring due to the resistance of the wiring itself. Therefore, the wiring itself that electrically connects the high heat generating components also generates a relatively high amount of heat. Therefore, when the high heat generating components are electrically connected by a circuit pattern formed on or inside a printed circuit board, it is necessary to dissipate the heat generated in the circuit pattern and keep the printed circuit board below the allowable temperature. The allowable temperature of the printed circuit board is, for example, 100°C or higher and 120°C or lower.

[0056] Figure 2 is a perspective view of the power conversion device 100 of Embodiment 1. Figure 3 is a perspective view of the first printed circuit board module 71 included in the power conversion device 100. Figure 4 is a perspective view of the second printed circuit board module 72 included in the power conversion device 100. Figure 5 is a perspective view of the third printed circuit board module 73 included in the power conversion device 100.

[0057] As Figure 2 shown, the power conversion device 100 of Embodiment 1 includes an external cooling body 21, a first printed circuit board module 71, a second printed circuit board module 72, and a third printed circuit board module 73. As will be described later using Figure 11 the first printed circuit board module 71, the second printed circuit board module 72, and the third printed circuit board module 73 are electrically connected by a wiring harness 86 or the like.

[0058] As Figures 2 - 5As shown, the power conversion device 100 includes an external cooling body 21, a first printed circuit board 31, a first insulating member 41, a first cooling body 51, a first fixing member 61, a second printed circuit board 32, a second insulating member 42, a second cooling body 52, a second fixing member 62, a third printed circuit board 33, a third insulating member 43, a third cooling body 53, a third fixing member 63, and electronic components. The external cooling body 21 has a main surface 21a.

[0059] The first printed circuit board (first substrate) 31 has a surface (first main surface) S1 on which electronic components (first components) are mounted and a back surface (second main surface) S2 facing the first cooling body 51. The second main surface S2 faces the first main surface S1. The first insulating member 41 is disposed between the second main surface S2 of the first printed circuit board 31 and the first cooling body 51. The first cooling body 51 is thermally connected to the second main surface S2 of the first printed circuit board 31 via the first insulating member 41. The first cooling body 51 is thermally bonded to the external cooling body 21. The external cooling body 21 is thermally connected to the first cooling body 51. The first cooling body 51 is thermally connected to the second main surface S2 of the first printed circuit board 31. The first fixing member 61 is configured to fix the first printed circuit board 31 to the first cooling body 51.

[0060] The second printed circuit board (second substrate) 32 has a surface (third main surface) S3 on which electronic components (second components) are mounted and a back surface (fourth main surface) S4 facing the second cooling body 52. The fourth main surface S4 faces the third main surface S3. The second insulating member 42 is disposed between the fourth main surface S4 of the second printed circuit board 32 and the second cooling body 52. The second cooling body 52 is thermally connected to the fourth main surface S4 of the second printed circuit board 32. The second cooling body 52 is thermally connected to the fourth main surface S4 of the second printed circuit board 32 via the second insulating member 42. The second cooling body 52 is configured to have a bottom surface that is the surface connecting to the surface 51a of the first cooling body 51 facing the first printed circuit board 31 and extends vertically. The second cooling body 52 extends in the direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1. The second cooling body 52 is thermally connected to the first cooling body 51. The second fixing member 62 is configured to fix the second printed circuit board 32 to the second cooling body 52.

[0061] The third printed circuit board (third substrate) 33 has a surface (fifth main surface) S5 on which electronic components (third components) are mounted and a back surface (sixth main surface) S6 facing the third cooling body 53. The sixth main surface S6 faces the fifth main surface S5. The third insulating member 43 is disposed between the sixth main surface S6 of the third printed circuit board 33 and the third cooling body 53. The third cooling body 53 is thermally connected to the sixth main surface S6 of the third printed circuit board 33 via the third insulating member 43. The third cooling body 53 is thermally connected to the sixth main surface S6 of the third printed circuit board 33. The third cooling body 53 is configured such that the surface connected to the surface 51a of the first cooling body 51 serves as a bottom surface and extends vertically. The third cooling body 53 extends in the direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1. The third cooling body 53 is thermally connected to the first cooling body 51. The third fixing member 63 is configured to fix the third printed circuit board 33 to the third cooling body 53.

[0062] In addition, the vertical direction is set to a direction substantially perpendicular to the main surface 21a of the external cooling body 21. The first cooling body 51 constitutes the bottom surface of the support body of the power conversion device 100. The second cooling body 52 and the third cooling body 53 constitute the side surfaces of the support body of the power conversion device 100.

[0063] The external cooling body 21 has a thermal conductivity of 1.0 W / (m·K) or more, preferably 10.0 W / (m·K) or more, and more preferably 100.0 W / (m·K) or more. The external cooling body 21 is formed of a metal material such as copper, iron, aluminum, iron alloy, aluminum alloy, or a resin having a relatively high thermal conductivity. The external cooling body 21 may have a pipe for allowing cooling water to pass therethrough inside. In addition, in order to promote heat dissipation to the surrounding atmosphere, the external cooling body 21 may have heat dissipation fins or the like.

[0064] Each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 may form a circuit pattern (not shown) on its surface or inside. The thickness of the circuit pattern is 1 μm or more and 2000 μm or less. In addition, the circuit pattern is formed of a conductive material. The circuit pattern is formed of, for example, copper, nickel, gold, aluminum, silver, tin, or the like, or an alloy thereof. The material constituting each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 may be, for example, glass fiber-reinforced epoxy resin, phenol resin, polyphenylene sulfide (PPS), polyether ether ketone (PEEK), or the like. In other words, each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 may be made of a material generally considered to have a low thermal conductivity. That is to say, each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 may be a general-purpose printed circuit board. In addition, each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 may be made of ceramics such as alumina, aluminum nitride, and silicon carbide.

[0065] Each of the first insulating member 41, the second insulating member 42, and the third insulating member 43 has electrical insulation. In addition, each of the first insulating member 41, the second insulating member 42, and the third insulating member 43 may have elasticity. In addition, each of the first insulating member 41, the second insulating member 42, and the third insulating member 43 may have a Young's modulus of 1 MPa or more and 100 MPa or less. Each of the first insulating member 41, the second insulating member 42, and the third insulating member 43 has a thermal conductivity of 0.1 W / (m·K) or more, preferably 1.0 W / (m·K) or more. Each of the first insulating member 41, the second insulating member 42, and the third insulating member 43 may be constituted of, for example, rubber materials such as silicon and polyurethane; resin materials such as acrylonitrile-butadiene-styrene (ABS), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), and phenol resin; polymer materials such as polyimide; ceramic materials such as alumina and aluminum nitride; phase change materials mainly made of silicon. In addition, each of the first insulating member 41, the second insulating member 42, and the third insulating member 43 may be constituted of a material obtained by mixing fine particles of alumina, aluminum nitride, boron nitride, or the like into silicone resin.

[0066] Each of the first cooling body 51, the second cooling body 52, and the third cooling body 53 has a thermal conductivity of 1.0 W / (m·K) or more, preferably 10.0 W / (m·K) or more, and more preferably 100.0 W / (m·K) or more. Each of the first cooling body 51, the second cooling body 52, and the third cooling body 53 is formed of a metal material such as copper, iron, aluminum, an iron alloy, an aluminum alloy, or a resin having a relatively high thermal conductivity. In addition, in order to make the potential of each of the first cooling body 51, the second cooling body 52, and the third cooling body 53 the same as the potential of the ground, it can be electrically connected to other components. In addition, each of the second cooling body 52 and the third cooling body 53 is directly or via other components connected and fixed to the first cooling body 51. Each of the second cooling body 52 and the third cooling body 53 is thermally connected to the first cooling body 51.

[0067] Thermal conduction members (first thermal conduction members) HC1 such as thermal conductive grease, thermal conductive sheets, and thermal conductive adhesives can be disposed on the contact surfaces between the first cooling body 51 and the second cooling body 52 and between the first cooling body 51 and the third cooling body 53. The thermal conduction members (first thermal conduction members) HC1 include at least any one of thermal conductive grease, thermal conductive sheets, and thermal conductive adhesives. The first cooling body 51 is thermally connected to each of the second cooling body 52 and the third cooling body 53 via the thermal conduction members (first thermal conduction members) HC1.

[0068] The first cooling body 51 can be in surface contact with the external cooling body 21. When the first cooling body 51 is in surface contact with the external cooling body 21, thermal conduction members such as thermal conductive grease, thermal conductive sheets, and thermal conductive adhesives can be disposed on the contact surface between the first cooling body 51 and the external cooling body 21.

[0069] Since the first cooling body 51 is thermally bonded to the external cooling body 21, the heat dissipation performance for the heat generated in the first printed circuit board module 71 is higher than the heat dissipation performance for the heat generated in the second printed circuit board module 72 and the third printed circuit board module 73. Therefore, the electronic components disposed in the first printed circuit board module 71, the second printed circuit board module 72, and the third printed circuit board module 73 can be exchanged, but it is preferable to dispose electronic components (high heat generating components) that generate particularly high heat in the first printed circuit board module 71. In the present embodiment, it is assumed that each of the switching elements 2a, 2b, 2c, and 2d is a particularly high heat generating component, and each of the switching elements 2a, 2b, 2c, and 2d is disposed in the first printed circuit board module 71.

[0070] Next, refer to Figures 3 - 10 An example of the first printed circuit board module 71, the second printed circuit board module 72, and the third printed circuit board module 73 will be described.

[0071] As Figure 3 shown, the first printed circuit board module 71 includes a first printed circuit board 31, a first insulating member 41, a first cooling body 51, a first fixing member 61, and electronic components (first components). The electronic components (first components) are mounted on the first printed circuit board 31. The electronic components (first components) are each of the switching elements 2a, 2b, 2c, 2d that are particularly high heat-generating components. The first insulating member 41 is disposed between the first printed circuit board 31 and the first cooling body 51. Preferably, the first insulating member 41 is in surface contact with the first printed circuit board 31 and the first cooling body 51. The first fixing member 61 fixes the first printed circuit board 31 to the first cooling body 51.

[0072] An input capacitor 1 and switching elements 2a, 2b, 2c, 2d are mounted on the surface 31a of the first printed circuit board 31 that is opposite to the surface facing the first cooling body 51. An input terminal 9 (not shown) is mounted on the surface 31a. Other electronic components can be mounted on the surface 31a. Additionally, other electronic components can be mounted on the surface of the first printed circuit board 31 that faces the first cooling body 51. The surface of the first printed circuit board 31 that faces the first cooling body 51 corresponds to the second main surface S2. The surface 31a of the first printed circuit board 31 that is opposite to the surface facing the first cooling body 51 corresponds to the first main surface S1.

[0073] As Figure 4 shown, the second printed circuit board module 72 includes a second printed circuit board 32, a second insulating member 42, a second cooling body 52, a second fixing member 62, and electronic components (second components). The electronic components (second components) are mounted on the second printed circuit board 32. The electronic components (second components) are the transformers 3, 4 and rectifying elements 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h that are particularly high heat-generating components. The second insulating member 42 is disposed between the fourth main surface S4 of the second printed circuit board 32 and the second cooling body 52. Preferably, the second insulating member 42 is in surface contact with the second printed circuit board 32 and the second cooling body 52. The second fixing member 62 fixes the second printed circuit board 32 to the second cooling body 52.

[0074] Rectifying elements 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h and transformers 3, 4 are mounted on the surface 32a of the second printed circuit board 32 that is opposite to the surface facing the second cooling body 52. Other electronic components can be mounted on the surface 32a. Additionally, other electronic components can be mounted on the surface of the second printed circuit board 32 that faces the second cooling body 52. The surface of the second printed circuit board 32 that faces the second cooling body 52 corresponds to the fourth main surface S4. The surface 32a of the second printed circuit board 32 that is opposite to the surface facing the second cooling body 52 corresponds to the third main surface S3.

[0075] Figure 6 is a cross-sectional view taken along line VI-VI shown in Figure 4 . As shown in Figure 6 , in the hole portion provided in the second printed circuit board 32, the upper core 81 and the lower core 82 are in contact with each other and magnetically coupled. On the second printed circuit board 32, coils 3a, 3b, 3c and coils 4a, 4b, 4c shown in Figure 1 are formed using wiring patterns (not shown). A transformer 3 is formed using the upper core 81, the lower core 82, and the coils 3a, 3b, 3c shown in Figure 1 . In addition, a transformer 4 is formed using the upper core 81, the lower core 82, and the coils 4a, 4b, 4c shown in Figure 1 .

[0076] The upper core 81 and the lower core 82 are, for example, ferrite cores such as Mn-Zn ferrite cores or Ni-Zn ferrite cores. The upper core 81 and the lower core 82 may also be amorphous cores or compacted cores.

[0077] The lower core 82 is provided in a groove 52a formed in the second cooling body 52. Preferably, the lower surface of the lower core 82 is in contact with the second cooling body 52. Heat conduction members such as heat conductive grease, heat conductive sheets, and heat conductive adhesives may be disposed between the lower surface of the lower core 82 and the second cooling body 52. The lower core 82 may be fixed to the second cooling body 52. The upper core 81 may be fixed to the lower core 82 using an adhesive. In addition, an insulating member (not shown) may be disposed between the lower core 82 and the second cooling body 52.

[0078] As shown in Figure 6 , preferably, the upper core 81 and the lower core 82 are pressed against the second cooling body 52 using a pressing spring 83. The pressing spring 83 is fixed to the second printed circuit board 32 using screws (not shown) or the like. In this case, since the upper core 81 and the lower core 82 are fixed to the second cooling body 52, position deviation can be prevented, and breakage of the upper core 81, the lower core 82, etc. due to vibration can be prevented. In addition, an insulating member (not shown) may be disposed between the upper core 81 and the pressing spring 83.

[0079] As shown in Figure 7 , the upper core 81 and the lower core 82 may also be pressed against the second cooling body 52 using a support pillar 84 and a pressing plate 85. The pressing plate 85 is fixed to the support pillar 84 so as to press the upper core 81 against the lower core 82. The support pillar 84 is fixed to the second printed circuit board 32. In addition, the support pillar 84 may penetrate through a hole portion (not shown) formed in the second printed circuit board 32 and be fixed to the second cooling body 52. In this case, since the upper core 81 and the lower core 82 are fixed to the second cooling body 52, position deviation can be prevented, and breakage of the upper core 81, the lower core 82, etc. due to vibration can be prevented. In addition, an insulating member (not shown) may be disposed between the upper core 81 and the pressing plate 85.

[0080] As shown Figure 5 in FIG. 2, the third printed circuit board module 73 includes a third printed circuit board 33, a third insulating member 43, a third cooling body 53, a third fixing member 63, and electronic components (third components). The electronic components (third components) are mounted on the third printed circuit board 33. The electronic components (third components) are reactors 6 and 7 that are particularly high heat-generating components. The third insulating member 43 is disposed between the third printed circuit board 33 and the third cooling body 53. Preferably, the third insulating member 43 is in surface contact with the third printed circuit board 33 and the third cooling body 53. The third fixing member 63 fixes the third printed circuit board 33 to the third cooling body 53.

[0081] On the surface 33a of the third printed circuit board 33 opposite to the surface facing the third cooling body 53, a smoothing capacitor 8 and reactors 6 and 7 are mounted. In addition, output terminals 10 (not shown) are mounted on the surface 33a. In addition, other electronic components may be mounted on the surface 33a. In addition, other electronic components may be mounted on the surface of the third printed circuit board 33 facing the third cooling body 53. The surface of the third printed circuit board 33 facing the third cooling body 53 corresponds to the sixth main surface S6. The surface 33a of the third printed circuit board 33 opposite to the surface facing the third cooling body 53 corresponds to the fifth main surface S5.

[0082] Figure 8 along Figure 5 the cross-sectional view taken along line VIII-VIII shown in FIG. 2. As shown Figure 8 in FIG. 2, in the hole portion provided in the third printed circuit board 33, the upper core 81 is in contact with the lower core 82 and magnetically coupled. Reactors 6 and 7 are formed by using wiring patterns (not shown) formed on the third printed circuit board 33, the upper core 81, and the lower core 82.

[0083] The lower core 82 is disposed in the groove 53a formed in the third cooling body 53. Preferably, the lower surface of the lower core 82 is in contact with the third cooling body 53. A heat conduction member such as heat conductive grease, a heat conductive sheet, or a heat conductive adhesive may be disposed between the lower surface of the lower core 82 and the third cooling body 53. The lower core 82 may be fixed to the third cooling body 53. In addition, an insulating member (not shown) may be disposed between the lower core 82 and the third cooling body 53.

[0084] As shown Figure 8 in FIG. 2, preferably, the upper core 81 and the lower core 82 are pressed against the third cooling body 53 by a pressing spring 83. The pressing spring 83 is fixed to the third printed circuit board 33 using screws or the like (not shown). In this case, since the upper core 81 and the lower core 82 are fixed to the third cooling body 53, position deviation can be prevented, and breakage of the upper core 81, the lower core 82, etc. due to vibration can be prevented. In addition, an insulating member (not shown) may be disposed between the upper core 81 and the pressing spring 83.

[0085] As Figure 9 shown, the upper core 81 and the lower core 82 can also be pressed against the third cooling body 53 by the support columns 84 and the pressing plate 85. The pressing plate 85 is fixed to the support columns 84 in such a manner as to press the upper core 81 against the lower core 82. The support columns 84 are fixed to the third printed circuit board 33. In addition, the support columns 84 may penetrate through a hole portion (not shown) formed in the third printed circuit board 33 and be fixed to the third cooling body 53. In this case, since the upper core 81 and the lower core 82 are fixed to the third cooling body 53, positional deviation can be prevented, and breakage of the upper core 81, the lower core 82, etc. due to vibration can be prevented. In addition, an insulating member (not shown) may be disposed between the upper core 81 and the pressing plate 85.

[0086] Figure 1 The control circuit unit 15 shown can be mounted on any one of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33. In addition, the control circuit unit 15 can be divided and mounted on at least two or more of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33.

[0087] Next, with reference to Figure 10 and Figure 11 a manufacturing method of the power conversion device 100 according to Embodiment 1 will be described.

[0088] As Figure 10 and Figure 11 shown, the power conversion device 100 is manufactured via a preparation process S100, an assembly process S200, and a connection process S300.

[0089] In the preparation process S100, electronic components including a first component, a second component, and a third component, the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33, the first cooling body 51, the second cooling body 52, and the third cooling body 53 are prepared.

[0090] In the assembly process S200, the first printed circuit board module 71, the second printed circuit board module 72, and the third printed circuit board module 73 are assembled respectively. In addition, the first printed circuit board module 71, the second printed circuit board module 72, and the third printed circuit board module 73 are electrically connected by a wire harness 86. That is, the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 are electrically connected.

[0091] In the connection process S300, each of the second printed circuit board module 72 and the third printed circuit board module 73 is connected and fixed to the first printed circuit board module 71.

[0092] In the assembling process S200, each of the first printed circuit board module 71, the second printed circuit board module 72, and the third printed circuit board module 73 is manufactured through an electronic component mounting process, a printed circuit board combining process, and a printed circuit board fixing process.

[0093] The assembling process of the first printed circuit board module 71 will be described. In the electronic component mounting process, electronic components (first components) are mounted on the first main surface S1 of the first printed circuit board 31 by flow soldering or reflow soldering, etc. In the printed circuit board combining process, the first cooling body 51, the first insulating member 41, and the first printed circuit board 31 on which the electronic components are mounted on the surface 31a are combined. At this time, the first cooling body 51 is thermally connected to the second main surface S2 of the first printed circuit board 31 facing the first main surface S1. In the printed circuit board fixing process, the first printed circuit board 31 is fixed to the first cooling body 51 via the first insulating member 41 using the first fixing member 61.

[0094] The assembling process of the second printed circuit board module 72 will be described. In the electronic component mounting process, electronic components (second components) are mounted on the third main surface S3 of the second printed circuit board 32 by flow soldering or reflow soldering, etc. In the printed circuit board combining process, the second cooling body 52, the second insulating member 42, the second printed circuit board 32 on which the electronic components are mounted on the surface 32a, the upper core 81, and the lower core 82 are combined. At this time, the second cooling body 52 is thermally connected to the fourth main surface S4 of the second printed circuit board 32 facing the third main surface S3. In the printed circuit board fixing process, the second printed circuit board 32 is fixed to the second cooling body 52 via the second insulating member 42 using the second fixing member 62.

[0095] The assembling process of the third printed circuit board module 73 will be described. In the electronic component mounting process, electronic components (third components) are mounted on the fifth main surface S5 of the third printed circuit board 33 by flow soldering or reflow soldering, etc. In the printed circuit board combining process, the third cooling body 53, the third insulating member 43, the third printed circuit board 33 on which the electronic components are mounted on the surface 33a, the upper core 81, and the lower core 82 are combined. At this time, the third cooling body 53 is thermally connected to the sixth main surface S6 of the third printed circuit board 33 facing the fifth main surface S5. In the printed circuit board fixing process, the third printed circuit board 33 is fixed to the third cooling body 53 via the third insulating member 43 using the third fixing member 63.

[0096] In the assembling process S200, each of the electronic components (second components) and the electronic components (third components) is respectively fixed to the grooves provided in each of the second printed circuit board 32 and the third printed circuit board 33.

[0097] As Figure 11As shown, each of the second printed circuit board module 72 and the third printed circuit board module 73 is electrically connected to the first printed circuit board module 71 by a wire harness 86. For example, the wire harness 86 has round hole terminals at both ends. In addition, a terminal block 87 is mounted on each of the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33. And it can be fixed to the terminal block 87 in a state where the round hole terminals of the wire harness 86 are inserted by screws or the like not shown, so that each of the second printed circuit board module 72 and the third printed circuit board module 73 is electrically connected to the first printed circuit board module 71.

[0098] Preferably, the terminal block 87 is arranged in such a way that the length of the wire harness 86 becomes shorter. In other words, as Figure 11 shown, preferably, the terminal block 87 is arranged in such a way that the distance between the two terminal blocks 87 connected by the wire harness 86 becomes shorter. In this case, since the length of the wire harness 86 becomes shorter, the resistance of the wire harness 86 can be reduced. Therefore, the Joule heat generated in the wire harness 86 can be reduced.

[0099] In the connection process, the second cooling body 52 included in the second printed circuit board module 72 and the third cooling body 53 included in the third printed circuit board module 73 are directly or via other components connected and fixed to the first cooling body 51 included in the first printed circuit board module 71. At this time, each of the second cooling body 52 and the third cooling body 53 is arranged to extend in the direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1. The first cooling body 51 is thermally coupled to the external cooling body 21 by methods such as surface contact with the external cooling body 21.

[0100] In the connection process S300, the second cooling body 52 and the third cooling body 53 are thermally connected to the first cooling body 51.

[0101] Next, the effects of the power conversion device 100 of Embodiment 1 will be described.

[0102] According to the power conversion device 100 of Embodiment 1, electronic components are mounted not only on the first printed circuit board 31 but also on the second printed circuit board 32 and the third printed circuit board 33. Therefore, even when the number of electronic components as high heat generating components increases, by mounting the electronic components on the second printed circuit board 32 and the third printed circuit board 33, the expansion of the first cooling body 51 can be suppressed. Therefore, the expansion of the bottom area of the power conversion device 100 can be suppressed. In addition, by mounting the electronic components on the second printed circuit board 32 and the third printed circuit board 33, the heat dissipation path from the electronic components mounted on the second printed circuit board 32 to the second cooling body 52 can be shortened, and the heat dissipation path from the electronic components mounted on the third printed circuit board 33 to the third cooling body 53 can be shortened. Therefore, the heat dissipation performance can be improved.

[0103] The power conversion device 100 according to Embodiment 1 includes an external cooling body 21 that is thermally connected to the first cooling body 51. As a heat dissipation path for dissipating heat generated in the circuit pattern formed on the surface or inside of the first printed circuit board 31 and heat generated in the switching elements 2a, 2b, 2c, 2d, which are high heat generating components mounted on the first printed circuit board 31, a first heat dissipation path can be formed that dissipates heat via the first printed circuit board 31, the first insulating member 41, and the first cooling body 51 to the external cooling body 21. Therefore, the heat dissipation performance of the power conversion device 100 with respect to heat generated in the circuit pattern formed on the surface or inside of the first printed circuit board 31 and heat generated in the high heat generating components mounted on the first printed circuit board 31 can be improved. As a result, the power conversion device 100 according to Embodiment 1 can operate with high output.

[0104] In addition, when the first insulating member 41 is in surface contact with the first printed circuit board 31 and the first cooling body 51, since the area of the contact surface between the first insulating member 41 and the first printed circuit board 31 and the area of the contact surface between the first insulating member 41 and the first cooling body 51 can be increased, the contact thermal resistance of the contact surface between the first insulating member 41 and the first printed circuit board 31 and the contact thermal resistance of the contact surface between the first insulating member 41 and the first cooling body 51 can be reduced, and the heat dissipation performance of the first heat dissipation path can be improved. As a result, the power conversion device 100 according to Embodiment 1 can operate with high output.

[0105] In addition, as a heat dissipation path for dissipating heat generated in the circuit pattern formed on the surface or inside of the second printed circuit board 32 and heat generated in the rectifying elements 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h and the transformers 3, 4, which are high heat generating components mounted on the second printed circuit board 32, a second heat dissipation path can be formed that dissipates heat via the second printed circuit board 32, the second insulating member 42, the second cooling body 52, and the first cooling body 51 to the external cooling body 21. Compared with the structure described in Patent Document 1, the second heat dissipation path does not include a plate-shaped substrate mounting portion, so the length of the heat dissipation path can be shortened and the heat dissipation performance can be improved. Therefore, the heat dissipation performance of the power conversion device 100 with respect to heat generated in the circuit pattern formed on the surface or inside of the second printed circuit board 32 and heat generated in the high heat generating components mounted on the second printed circuit board 32 can be improved. As a result, the power conversion device 100 according to Embodiment 1 can operate with high output.

[0106] In addition, when the second insulating member 42 is in surface contact with the second printed circuit board 32 and the second cooling body 52, since the contact area between the second insulating member 42 and the second printed circuit board 32 and the contact area between the second insulating member 42 and the second cooling body 52 can be increased, the contact thermal resistance of the contact surface between the second insulating member 42 and the second printed circuit board 32 and the contact thermal resistance of the contact surface between the second insulating member 42 and the second cooling body 52 can be reduced, and the heat dissipation performance of the second heat dissipation path can be improved. As a result, the power conversion device 100 of Embodiment 1 can operate with high output.

[0107] In addition, as Figure 7 shown, when the upper core 81 and the lower core 82 are fixed to the second cooling body 52 by the support columns 84 and the pressing plate 85 fixed to the second cooling body 52, since the heat generated in the transformers 3 and 4 can be dissipated to the external cooling body 21 via the pressing plate 85, the support columns 84, the second cooling body 52, and the first cooling body 51, the heat dissipation performance of the power conversion device 100 for the heat generated in the transformers 3 and 4 can be improved. As a result, the power conversion device 100 of Embodiment 1 can operate with high output.

[0108] In addition, when the lower surface of the lower core 82 is in direct contact with the second cooling body 52, or when the lower surface of the lower core 82 is in contact with the second cooling body 52 via a heat conduction member such as heat conduction grease, a heat conduction sheet, or a heat conduction adhesive, or when the lower surface of the lower core 82 is in contact with the second cooling body 52 via an insulating member, since the heat generated in the transformers 3 and 4 can be dissipated to the external cooling body 21 via the second cooling body 52 and the first cooling body 51, the heat dissipation performance of the power conversion device 100 for the heat generated in the transformers 3 and 4 can be improved. As a result, the power conversion device 100 of Embodiment 1 can operate with high output.

[0109] In addition, as a heat dissipation path for dissipating the heat generated in the circuit pattern formed on the surface or inside of the third printed circuit board 33 and the heat generated in the reactors 6 and 7 which are high heat generating components mounted on the third printed circuit board 33, a third heat dissipation path can be formed which dissipates heat to the external cooling body 21 via the third printed circuit board 33, the third insulating member 43, the third cooling body 53, and the first cooling body 51. Compared with the structure described in Patent Document 1, the third heat dissipation path does not include a plate-shaped substrate mounting portion, so the length of the heat dissipation path can be shortened and the heat dissipation performance can be improved. Therefore, the heat dissipation performance of the power conversion device 100 for the heat generated in the circuit pattern formed on the surface or inside of the third printed circuit board 33 and the heat generated in the high heat generating components mounted on the third printed circuit board 33 can be improved. As a result, the power conversion device 100 of Embodiment 1 can operate with high output.

[0110] In addition, when the third insulating member 43 is in surface contact with the third printed circuit board 33 and the third cooling body 53, since the contact area between the third insulating member 43 and the third printed circuit board 33 and the contact area between the third insulating member 43 and the third cooling body 53 can be increased, the contact thermal resistance of the contact surface between the third insulating member 43 and the third printed circuit board 33 and the contact thermal resistance of the contact surface between the third insulating member 43 and the third cooling body 53 can be reduced, and the heat dissipation performance of the third heat dissipation path can be improved. As a result, the power conversion device 100 of Embodiment 1 can operate at a high output.

[0111] In addition, as Figure 9 shown, when the upper core 81 and the lower core 82 are fixed to the third cooling body 53 by the support column 84 and the pressing plate 85 fixed to the third cooling body 53, since the heat generated in the reactors 6 and 7 can be dissipated to the external cooling body 21 via the pressing plate 85, the support column 84, the third cooling body 53 and the first cooling body 51, the heat dissipation performance of the power conversion device 100 for the heat generated in the reactors 6 and 7 can be improved. As a result, the power conversion device 100 of Embodiment 1 can operate at a high output.

[0112] In addition, when the lower surface of the lower core 82 is in direct contact with the third cooling body 53, or when the lower surface of the lower core 82 is in contact with the third cooling body 53 via a heat conduction member such as a heat conductive grease, a heat conductive sheet, or a heat conductive adhesive, or when the lower surface of the lower core 82 is in contact with the third cooling body 53 via an insulating member, since the heat generated in the reactors 6 and 7 can be dissipated to the external cooling body 21 via the third cooling body 53 and the first cooling body 51, the heat dissipation performance of the power conversion device 100 for the heat generated in the reactors 6 and 7 can be improved. As a result, the power conversion device 100 of Embodiment 1 can operate at a high output.

[0113] In addition, since the first cooling body 51 is thermally coupled to the external cooling body 21, the heat dissipation performance of the first heat dissipation path is higher than that of the second and third heat dissipation paths. Therefore, by mounting particularly high-heat-generating electronic components among the high-heat-generating electronic components on the first printed circuit board 31, the heat dissipation performance of the power conversion device 100 for the heat generated in these components can be improved. As a result, the power conversion device 100 of Embodiment 1 can operate at a high output.

[0114] Preferably, the thickness of the first cooling body 51 in a direction substantially perpendicular to the surface 31a of the first printed circuit board 31 is reduced. Thereby, since the lengths of the first, second, and third heat dissipation paths can be shortened, the heat dissipation performance can be improved.

[0115] Preferably, the thickness of the second cooling body 52 in a direction substantially perpendicular to the surface 32a of the second printed circuit board 32 is increased. Thereby, since the thermal resistance of the second cooling body 52 included in the second heat dissipation path can be reduced, the heat dissipation performance can be improved.

[0116] Preferably, the thickness of the third cooling body 53 in a direction substantially perpendicular to the surface 33a of the third printed circuit board 33 is increased. Thereby, since the thermal resistance of the third cooling body 53 included in the third heat dissipation path can be reduced, the heat dissipation performance can be improved.

[0117] That is, referring to Figure 30 , preferably, the thickness of the first cooling body 51 in the direction in which the second main surface S2 faces the first main surface S1 is thinner than the thickness of the second cooling body 52 in the direction in which the fourth main surface S4 faces the third main surface S3 and the thickness of the third cooling body 53 in the direction in which the sixth main surface S6 faces the fifth main surface S5.

[0118] In addition, in the power conversion device 100 of Embodiment 1, the first cooling body 51 can be thermally connected to the first printed circuit board 31 via the first insulating member 41. The second cooling body 52 can be thermally connected to the second printed circuit board 32 via the second insulating member 42. The third cooling body 53 can be thermally connected to the third printed circuit board 33 via the third insulating member 43.

[0119] In addition, in the power conversion device 100 of Embodiment 1, the second cooling body 52 is thermally connected to the first cooling body 51, and the third cooling body 53 is thermally connected to the first cooling body 51. Therefore, the heat generated in the electronic components mounted on the second printed circuit board 32 can be dissipated from the first cooling body 51 via the second cooling body 52, and the heat generated in the electronic components mounted on the third printed circuit board 33 can be dissipated from the first cooling body 51 via the third cooling body 53.

[0120] In addition, in the power conversion device 100 of Embodiment 1, the first cooling body 51 is thermally connected to each of the second cooling body 52 and the third cooling body 53 via the first heat conductive member HC1. Therefore, the heat transfer efficiency from the second cooling body 52 to the first cooling body 51 can be improved by using the first heat conductive member HC1, and the heat transfer efficiency from the third cooling body 53 to the first cooling body 51 can be improved.

[0121] In addition, in the power conversion device 100 of Embodiment 1, the first cooling body 51, the second cooling body 52, and the third cooling body 53 constitute a support body of the power conversion device 100. Therefore, compared with the case where the cooling body is not also used as a support body, the amount of the support body can be reduced, and as a result, the power conversion device 100 of Embodiment 1 can be miniaturized.

[0122] As described above, in the power conversion device 100 of Embodiment 1, the first coolant body 51, the second coolant body 52, and the third coolant body 53 constitute the support body of the power conversion device 100. However, a support body may be additionally and newly provided on the basis of the first coolant body 51 to the third coolant body 53.

[0123] In addition, the first coolant body 51, the second coolant body 52, and the third coolant body 53 can be used as current paths. For example, in Figure 32 the circuit diagram of Modification 6 of the power conversion device of Embodiment 1 shown, the current path between A - A' can use the first coolant body 51, the second coolant body 52, and the third coolant body 53. At this time, the first coolant body 51, the second coolant body 52, and the third coolant body 53 are electrically connected. In addition, at this time, the circuit pattern formed on the printed circuit board is electrically connected to the coolant body at necessary parts. That is, between the first coolant body 51 and the circuit pattern formed on the first printed circuit board 31, between the second coolant body 52 and the circuit pattern formed on the second printed circuit board 32, and between the third coolant body 53 and the circuit pattern formed on the third printed circuit board 33 can be electrically connected as needed. Regarding the electrical connection, for example, by making the fixing members 61, 62, 63 made of conductive materials such as metal screws, the first coolant body 51 and the circuit pattern formed on the first printed circuit board 31 are electrically connected by the first fixing member 61, the second coolant body 52 and the circuit pattern formed on the second printed circuit board 32 are electrically connected by the second fixing member 62, and the third coolant body 53 and the circuit pattern formed on the third printed circuit board 33 are electrically connected by the third fixing member 63.

[0124] By using the first coolant body 51, the second coolant body 52, and the third coolant body 53 as current paths, the number of wire harnesses 86 that electrically connect each of the first printed circuit board module 71, the second printed circuit board module 72, and the third printed circuit board module 73 can be reduced, and the space for arranging the wire harnesses 86 can be reduced. As a result, the power conversion device 100 of Embodiment 1 can be miniaturized.

[0125] In addition, in the structure described in Patent Document 1, electronic components are arranged in a space formed in a housing. In the structure described in Patent Document 1, as in the present embodiment, when a printed circuit board is fixed to the bottom surface and side surface of the housing via an insulating member, it is necessary to arrange the insulating member, arrange the printed circuit board, fix the printed circuit board, and electrically connect the printed circuit boards in a substantially enclosed space, resulting in poor workability. As a result, deviations in the thickness of the insulating member are likely to occur, and thermal design considering this situation is required. In addition, when electrically connecting terminal blocks fixed to a printed circuit board with a wire harness having round-hole terminals at both ends, it is necessary to screw-fix the round-hole terminals at both ends of the wire harness to the terminal blocks in a substantially enclosed space. Therefore, when the substantially enclosed space is narrow, it is necessary to design the fixing position of the terminal block in consideration of the screw-fixing operation.

[0126] In contrast, the manufacturing method of the power conversion device 100 according to Embodiment 1 includes a preparation process S100, an assembly process S200, and a connection process S300. Therefore, it is not necessary to perform operations such as arranging the first insulating member 41, the second insulating member 42, and the third insulating member 43 on the first cooling body 51 constituting the bottom surface of the support body, the second cooling body 52 and the third cooling body 53 constituting the side surface of the support body, and fixing the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33, and electrically connecting the first printed circuit board module 71, the second printed circuit board module 72, and the third printed circuit board module 73 in a substantially enclosed space. As a result, it is not necessary to perform thermal design considering the thickness deviation of the first insulating member 41, the second insulating member 42, and the third insulating member 43 caused by poor workability. In addition, it is not necessary to design the mounting position of the terminal block considering the screw-fixing operation, which is caused by the necessity of screw-fixing the round-hole terminals at both ends of the wire harness 86 to the terminal block 87 in a substantially enclosed space when electrically connecting the terminal blocks 87 with a wire harness 86 having round-hole terminals at both ends.

[0127] In addition, in the manufacturing method of the power conversion device 100 according to Embodiment 1, in the connection process S300, the second cooling body 52 and the third cooling body 53 are thermally connected to the first cooling body 51.

[0128] In addition, in the manufacturing method of the power conversion device 100 according to Embodiment 1, in the assembly process S200, each of the electronic components (second component) and the electronic components (third component) is fixed to a groove provided on each of the second printed circuit board 32 and the third printed circuit board 33. Therefore, the electronic components can be reliably fixed.

[0129] As Figure 12As shown, the power conversion device 100 of Embodiment 1 can be configured such that the first cooling body 51 is disposed while being sandwiched between the second cooling body 52 and the third cooling body 53.

[0130] As Figure 13 shown, in the power conversion device 100 of Embodiment 1, the first cooling body 51 can be integrally formed with the external cooling body 21. In this case, the first cooling body 51 also serves as the external cooling body 21. The first cooling body 51 is thermally coupled to the external cooling body 21 by a method such as being integrally formed with the external cooling body 21.

[0131] Embodiment 2.

[0132] Next, the power conversion device 100 of Embodiment 2 will be described with reference to Figure 14 As long as not particularly stated, Embodiment 2 has the same structure, operation, and effects as those of Embodiment 1 described above. Therefore, the same reference numerals are given to the same structures as those of Embodiment 1 described above, and redundant description will not be repeated.

[0133] The power conversion device 100 of Embodiment 2 has substantially the same structure as the power conversion device 100 of Embodiment 1. The power conversion device 100 of Embodiment 2 is different from the power conversion device 100 of Embodiment 1 in that it includes a fourth cooling body 54 and a fifth cooling body 55.

[0134] The fourth cooling body 54 is configured to have a bottom surface that is the surface connected to the surface 51a of the first cooling body 51 and extends vertically. The fourth cooling body 54 extends in a direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1. The fifth cooling body 55 is configured to have a bottom surface that is the surface connected to the surface 51a of the first cooling body 51 and extends vertically. The fifth cooling body 55 extends in a direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1.

[0135] Each of the fourth cooling body 54 and the fifth cooling body 55 is directly or via other members, connected and fixed to at least one of the first cooling body 51, the second cooling body 52, and the third cooling body 53. Each of the fourth cooling body 54 and the fifth cooling body 55 is thermally connected to each of the first cooling body 51, the second cooling body 52, and the third cooling body 53. The fourth cooling body 54 is thermally connected to the first cooling body 51, the second cooling body 52, and the third cooling body 53. The fifth cooling body 55 is thermally connected to the first cooling body 51, the second cooling body 52, and the third cooling body 53.

[0136] A heat conduction member such as a heat conductive grease, a heat conductive sheet, a heat conductive adhesive (second heat conduction member) HC2, etc. may be disposed on the contact surface between each of the fourth cooling body 54 and the fifth cooling body 55 and each of the first cooling body 51, the second cooling body 52, and the third cooling body 53. The heat conduction member (second heat conduction member) HC2 includes at least any one of a heat conductive grease, a heat conductive sheet, and a heat conductive adhesive. The fourth cooling body 54 is thermally connected to each of the first cooling body 51, the second cooling body 52, and the third cooling body 53 via the heat conduction member (second heat conduction member) HC2. The fifth cooling body 55 is thermally connected to each of the first cooling body 51, the second cooling body 52, and the third cooling body 53 via the heat conduction member (second heat conduction member) HC2. Each of the fourth cooling body 54 and the fifth cooling body 55 constitutes a side surface of the support body of the power conversion device 100.

[0137] Thus, the power conversion device 100 of Embodiment 2 can also achieve the same effects as the power conversion device 100 of Embodiment 1. Moreover, as heat dissipation paths for dissipating heat generated in the circuit pattern formed on the surface or inside of the second printed circuit board 32 and heat generated in the rectifying elements 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h and the transformers 3, 4 which are high heat generating components mounted on the second printed circuit board 32, in addition to the second heat dissipation path that dissipates heat to the external cooling body 21 via the second printed circuit board 32, the second insulating member 42, the second cooling body 52 and the first cooling body 51, the following two heat dissipation paths are also formed. The first is the heat dissipation path that dissipates heat to the external cooling body 21 via the second printed circuit board 32, the second insulating member 42, the second cooling body 52, the fourth cooling body 54 and the first cooling body 51. The second is the heat dissipation path that dissipates heat to the external cooling body 21 via the second printed circuit board 32, the second insulating member 42, the second cooling body 52, the fifth cooling body 55 and the first cooling body 51. Therefore, the heat dissipation performance of the power conversion device 100 for heat generated in the circuit pattern formed on the surface or inside of the second printed circuit board 32 and heat generated in the high heat generating components mounted on the second printed circuit board 32 can be improved. In addition, as heat dissipation paths for dissipating heat generated in the circuit pattern formed on the surface or inside of the third printed circuit board 33 and heat generated in the reactors 6, 7 which are high heat generating components mounted on the third printed circuit board 33, in addition to the third heat dissipation path that dissipates heat to the external cooling body 21 via the third printed circuit board 33, the third insulating member 43, the third cooling body 53 and the first cooling body 51, the following two heat dissipation paths are also formed. The first is the heat dissipation path that dissipates heat to the external cooling body 21 via the third printed circuit board 33, the third insulating member 43, the third cooling body 53, the fourth cooling body 54 and the first cooling body 51. The second is the heat dissipation path that dissipates heat to the external cooling body 21 via the third printed circuit board 33, the third insulating member 43, the third cooling body 53, the fifth cooling body 55 and the first cooling body 51. Therefore, the heat dissipation performance of the power conversion device 100 for heat generated in the circuit pattern formed on the surface or inside of the third printed circuit board 33 and heat generated in the high heat generating components mounted on the third printed circuit board 33 can be improved. As a result, the power conversion device 100 of Embodiment 2 can operate with high output.

[0138] In addition, in the power conversion device 100 of Embodiment 2, the fourth cooling body 54 is thermally connected to each of the first cooling body 51, the second cooling body 52, and the third cooling body 53 via a heat conduction member (second heat conductive member) HC2. The fifth cooling body 55 is thermally connected to each of the first cooling body 51, the second cooling body 52, and the third cooling body 53 via a heat conduction member (second heat conductive member) HC2. Therefore, the heat transfer efficiency from the fourth cooling body 54 to the first cooling body 51, the second cooling body 52, and the third cooling body 53 can be improved by using the second heat conductive member HC2, and the heat transfer efficiency from the fifth cooling body 55 to the first cooling body 51, the second cooling body 52, and the third cooling body 53 can be improved.

[0139] As Figure 15 shown, the power conversion device 100 of Embodiment 2 may be configured such that the first cooling body 51 is disposed while being sandwiched between the fourth cooling body 54 and the fifth cooling body 55.

[0140] In addition, in the power conversion device 100 of Embodiment 2, as Figure 14 or Figure 15 shown, the second printed circuit board 32 and the third printed circuit board 33 may be arranged such that the surface (third main surface) S3 of the second printed circuit board 32 on which electronic components are mounted faces the surface (fifth main surface) S5 of the third printed circuit board 33 on which electronic components are mounted.

[0141] When the second printed circuit board 32 and the third printed circuit board 33 are arranged such that the surface (third main surface) S3 of the second printed circuit board 32 on which electronic components are mounted faces the surface (fifth main surface) S5 of the third printed circuit board 33 on which electronic components are mounted, when the first cooling body 51 to the fifth cooling body 55 are made of metal, the first cooling body 51 to the fifth cooling body 55 function as an electromagnetic shielding cover that prevents the power conversion device 100 from malfunctioning due to electromagnetic wave noise emitted from other electronic devices or the like arranged around the power conversion device 100. In addition, generally, with the operation of the power conversion device, electromagnetic waves are emitted from the inverter circuit unit 11 composed of the switching elements 2a, 2b, 2c, 2d, the transformer unit 12 composed of the transformers 3, 4, the rectifier circuit unit 13 composed of eight rectifier elements 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, and the smoothing circuit unit 14 composed of the reactors 6, 7 and the smoothing capacitor 8. When the second printed circuit board 32 and the third printed circuit board 33 are arranged such that the surface (third main surface) S3 of the second printed circuit board 32 on which electronic components are mounted faces the surface (fifth main surface) S5 of the third printed circuit board 33 on which electronic components are mounted, when the first cooling body 51 to the fifth cooling body 55 are made of metal, the first cooling body 51 to the fifth cooling body 55 function as an electromagnetic shielding cover that prevents the electromagnetic wave noise emitted from the inverter circuit unit 11 composed of the switching elements 2a, 2b, 2c, 2d, the transformer unit 12 composed of the transformers 3, 4, the rectifier circuit unit 13 composed of eight rectifier elements 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, and the smoothing circuit unit 14 composed of the reactors 6, 7 and the smoothing capacitor 8 from being emitted to the outside of the power conversion device 100. Therefore, compared with the case where the cooling body is not also used as an electromagnetic shielding cover, the amount of the electromagnetic shielding cover can be reduced, and as a result, the power conversion device 100 of Embodiment 2 can be miniaturized.

[0142] As described above, in the power conversion device 100 of Embodiment 2, when the second printed circuit board 32 and the third printed circuit board 33 are arranged such that the surface (third main surface) S3 of the second printed circuit board 32 on which electronic components are mounted faces the surface (fifth main surface) S5 of the third printed circuit board 33 on which electronic components are mounted, when the first cooling body 51 to the fifth cooling body 55 are made of metal, the first cooling body 51 to the fifth cooling body 55 also function as an electromagnetic shielding cover. However, an electromagnetic shielding cover can also be newly added on the basis of the first cooling body 51 to the fifth cooling body 55.

[0143] Embodiment 3.

[0144] Next, referring to Figures 16 - 21Describe the power conversion device 100 of Embodiment 3. Unless otherwise specified, Embodiment 3 has the same structure, operation, and effects as Embodiment 2 described above. Therefore, the same reference numerals are assigned to the same structures as those in Embodiment 2, and no repeated description is provided.

[0145] The power conversion device 100 of Embodiment 3 has substantially the same structure as the power conversion device 100 of Embodiment 2. The power conversion device 100 of Embodiment 3 is different from the power conversion device 100 of Embodiment 2 in that it includes a fourth printed circuit board module 74 and a fifth printed circuit board module 75.

[0146] The fourth printed circuit board module 74 includes a fourth printed circuit board 34, a fourth insulating member 44, a fourth cooling body 54, a fourth fixing member 64, and electronic components.

[0147] The fourth printed circuit board (fourth substrate) 34 has a surface (seventh main surface) S7 on which electronic components (fourth components) are mounted and a back surface (eighth main surface) S8 facing the fourth cooling body 54. The seventh main surface S7 faces the eighth main surface S8. The fourth insulating member 44 is disposed between the eighth main surface S8 of the fourth printed circuit board 34 and the fourth cooling body 54. The fourth cooling body 54 is thermally connected to the eighth main surface S8 of the fourth printed circuit board 34. The fourth cooling body 54 is thermally connected to the eighth main surface S8 of the fourth printed circuit board 34 via the fourth insulating member 44. The fourth cooling body 54 is configured such that the surface connected to the surface 51a of the first cooling body 51 facing the first printed circuit board 31 serves as the bottom surface and extends vertically. The fourth cooling body 54 extends in the direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1. The fourth cooling body 54 is thermally connected to each of the first cooling body 51, the second cooling body 52, and the third cooling body 53. The fourth fixing member 64 is configured to fix the fourth printed circuit board 34 to the fourth cooling body 54.

[0148] The fifth printed circuit board module 75 includes a fifth printed circuit board 35, a fifth insulating member 45, a fifth cooling body 55, a fifth fixing member 65, and electronic components.

[0149] The fifth printed circuit board (fifth substrate) 35 has a front surface (ninth main surface) S9 on which electronic components (fifth components) are mounted and a back surface (tenth main surface) S10 facing the fifth cooling body 55. The ninth main surface S9 faces the tenth main surface S10. The fifth insulating member 45 is disposed between the tenth main surface S10 of the fifth printed circuit board 35 and the fifth cooling body 55. The fifth cooling body 55 is thermally connected to the tenth main surface S10 of the fifth printed circuit board 35. The fifth cooling body 55 is thermally connected to the tenth main surface S10 of the fifth printed circuit board 35 via the fifth insulating member 45. The fifth cooling body 55 is configured such that the surface connected to the surface 51a of the first cooling body 51 facing the first printed circuit board 31 is the bottom surface and extends vertically. The fifth cooling body 55 extends in the direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1. The fifth cooling body 55 is thermally connected to each of the first cooling body 51, the second cooling body 52, and the third cooling body 53. The fifth fixing member 65 is configured to fix the fifth printed circuit board 35 to the fifth cooling body 55.

[0150] The power conversion device 100 according to the third embodiment includes a first printed circuit board module 71, a second printed circuit board module 72, a third printed circuit board module 73, a fourth printed circuit board module 74, and a fifth printed circuit board module 75. The first printed circuit board module 71, the second printed circuit board module 72, the third printed circuit board module 73, the fourth printed circuit board module 74, and the fifth printed circuit board module 75 are electrically connected by a wire harness or the like. That is, the first printed circuit board 31, the second printed circuit board 32, the third printed circuit board 33, the fourth printed circuit board 34, and the fifth printed circuit board 35 are electrically connected.

[0151] Next, with reference to Figures 17 - 21 , an example of the first printed circuit board module 71, the second printed circuit board module 72, the third printed circuit board module 73, the fourth printed circuit board module 74, and the fifth printed circuit board module 75 in the power conversion device 100 according to the third embodiment will be described.

[0152] As Figure 17 shown, the first printed circuit board module 71 includes a first printed circuit board 31, a first insulating member 41, a first cooling body 51, a first fixing member 61, and electronic components. The electronic components are mounted on the first printed circuit board 31. The first insulating member 41 is disposed between the first printed circuit board 31 and the first cooling body 51. The first fixing member 61 fixes the first printed circuit board 31 to the first cooling body 51.

[0153] On the surface 31a of the first printed circuit board 31 opposite to the surface facing the first cooling body 51, an input capacitor 1 and switching elements 2a, 2b, 2c, 2d are mounted. An input terminal 9 (not shown) is mounted on the surface 31a. Other electronic components can be mounted on the surface 31a. Additionally, other electronic components can be mounted on the surface of the first printed circuit board 31 facing the first cooling body 51.

[0154] As Figure 18 shown, the second printed circuit board module 72 includes a second printed circuit board 32, a second insulating member 42, a second cooling body 52, a second fixing member 62, and electronic components. The electronic components are mounted on the second printed circuit board 32. The second insulating member 42 is disposed between the second printed circuit board 32 and the second cooling body 52. The second fixing member 62 fixes the second printed circuit board 32 to the second cooling body 52.

[0155] On the surface 32a of the second printed circuit board 32 opposite to the surface facing the second cooling body 52, rectifying elements 5a, 5b, 5c, 5d and a transformer 3 are mounted. Other electronic components can be mounted on the surface 32a. Additionally, other electronic components can be mounted on the surface of the second printed circuit board 32 facing the second cooling body 52.

[0156] As Figure 19 shown, the third printed circuit board module 73 includes a third printed circuit board 33, a third insulating member 43, a third cooling body 53, a third fixing member 63, and electronic components. The electronic components are mounted on the third printed circuit board 33. The third insulating member 43 is disposed between the third printed circuit board 33 and the third cooling body 53. The third fixing member 63 fixes the third printed circuit board 33 to the third cooling body 53.

[0157] On the surface 33a of the third printed circuit board 33 opposite to the surface facing the third cooling body 53, rectifying elements 5e, 5f, 5g, 5h and a transformer 4 are mounted. Other electronic components can be mounted on the surface 33a. Additionally, other electronic components can be mounted on the surface of the third printed circuit board 33 facing the third cooling body 53.

[0158] As Figure 20 shown, the fourth printed circuit board module 74 includes a fourth printed circuit board 34, a fourth insulating member 44, a fourth cooling body 54, a fourth fixing member 64, and electronic components (fourth components). The electronic components (fourth components) are mounted on the fourth printed circuit board 34. The electronic components (fourth components) are a reactor 6 which is a particularly high heat generating component. The fourth insulating member 44 is disposed between the fourth printed circuit board 34 and the fourth cooling body 54. The fourth fixing member 64 fixes the fourth printed circuit board 34 to the fourth cooling body 54. Preferably, the fourth insulating member 44 is in surface contact with the fourth printed circuit board 34 and the fourth cooling body 54.

[0159] A smoothing capacitor 8 and a reactor 6 are mounted on the opposite surface 34a of the fourth printed circuit board 34 from the surface facing the fourth cooling body 54. Output terminals 10 (not shown) are mounted on the surface 34a. Other electronic components can be mounted on the surface 34a. The surface of the fourth printed circuit board 34 facing the fourth cooling body 54 corresponds to the eighth main surface S8. The opposite surface 34a of the fourth printed circuit board 34 from the surface facing the fourth cooling body 54 corresponds to the seventh main surface S7. Additionally, other electronic components can be mounted on the surface of the fourth printed circuit board 34 facing the fourth cooling body 54.

[0160] As Figure 21 shown, the fifth printed circuit board module 75 includes a fifth printed circuit board 35, a fifth insulating member 45, a fifth cooling body 55, a fifth fixing member 65, and electronic components (fifth components). The electronic components (fifth components) are mounted on the fifth printed circuit board 35. The electronic components (fifth components) are reactors 7, which are particularly high heat-generating components. The fifth insulating member 45 is disposed between the fifth printed circuit board 35 and the fifth cooling body 55. The fifth fixing member 65 fixes the fifth printed circuit board 35 to the fifth cooling body 55. Preferably, the fifth insulating member 45 is in surface contact with the fifth printed circuit board 35 and the fifth cooling body 55.

[0161] A smoothing capacitor 8 and a reactor 7 are mounted on the opposite surface 35a of the fifth printed circuit board 35 from the surface facing the fifth cooling body 55. Additionally, output terminals 10 (not shown) are mounted on the surface 35a. Other electronic components can be mounted on the surface 35a. The surface of the fifth printed circuit board 35 facing the fifth cooling body 55 corresponds to the tenth main surface S10. The opposite surface 35a of the fifth printed circuit board 35 from the surface facing the fifth cooling body 55 corresponds to the ninth main surface S9. Additionally, other electronic components can be mounted on the surface of the fifth printed circuit board 35 facing the fifth cooling body 55.

[0162] In this way, the power conversion device 100 of Embodiment 3 can also achieve the same effects as the power conversion device 100 of Embodiment 2. Moreover, in the power conversion device 100 of Embodiment 3, as a heat dissipation path for dissipating heat generated in the circuit pattern formed on the surface or inside of the fourth printed substrate 34 and heat generated in the smoothing capacitor 8 and the reactor 6 which are high heat-generating components mounted on the fourth printed substrate 34, a fourth heat dissipation path can be formed to dissipate heat to the external cooling body 21 via the fourth printed substrate 34, the fourth insulating member 44, the fourth cooling body 54 and the first cooling body 51. Compared with the structure described in Patent Document 1, the fourth heat dissipation path does not include a plate-shaped substrate mounting portion, so the length of the heat dissipation path can be shortened, and thus the heat dissipation performance can be improved. Therefore, the heat dissipation performance of the power conversion device 100 for heat generated in the circuit pattern formed on the surface or inside of the fourth printed substrate 34 and heat generated in the high heat-generating components mounted on the fourth printed substrate 34 can be improved. As a result, the power conversion device 100 of Embodiment 3 can operate with high output.

[0163] In addition, when the fourth insulating member 44 is in surface contact with the fourth printed substrate 34 and the fourth cooling body 54, the contact area between the fourth insulating member 44 and the fourth printed substrate 34 and the contact area between the fourth insulating member 44 and the fourth cooling body 54 can be increased. Therefore, since the contact thermal resistance of the contact surface between the fourth insulating member 44 and the fourth printed substrate 34 and the contact thermal resistance of the contact surface between the fourth insulating member 44 and the fourth cooling body 54 can be reduced, the heat dissipation performance of the fourth heat dissipation path can be improved. As a result, the power conversion device 100 of Embodiment 3 can operate with high output.

[0164] In addition, as a heat dissipation path for dissipating heat generated in the circuit pattern formed on the surface or inside of the fifth printed substrate 35 and heat generated in the smoothing capacitor 8 and the reactor 7 which are high heat-generating components mounted on the fifth printed substrate 35, a fifth heat dissipation path can be formed to dissipate heat to the external cooling body 21 via the fifth printed substrate 35, the fifth insulating member 45, the fifth cooling body 55 and the first cooling body 51. Compared with the structure described in Patent Document 1, the fifth heat dissipation path does not include a plate-shaped substrate mounting portion, so the length of the heat dissipation path can be shortened, and thus the heat dissipation performance can be improved. Therefore, the heat dissipation performance of the power conversion device 100 for heat generated in the circuit pattern formed on the surface or inside of the fifth printed substrate 35 and heat generated in the high heat-generating components mounted on the fifth printed substrate 35 can be improved. As a result, the power conversion device 100 of Embodiment 3 can operate with high output.

[0165] In addition, when the fifth insulating member 45 is in surface contact with the fifth printed circuit board 35 and the fifth cooling body 55, since the contact area between the fifth insulating member 45 and the fifth printed circuit board 35 and the contact area between the fifth insulating member 45 and the fifth cooling body 55 can be increased, the contact thermal resistance of the contact surface between the fifth insulating member 45 and the fifth printed circuit board 35 and the contact thermal resistance of the contact surface between the fifth insulating member 45 and the fifth cooling body 55 can be reduced, so that the heat dissipation performance of the fifth heat dissipation path can be improved. As a result, the power conversion device 100 of Embodiment 3 can operate with high output.

[0166] Preferably, the thickness of the fourth cooling body 54 in a direction substantially perpendicular to the surface 34a of the fourth printed circuit board 34 is increased. Thereby, since the thermal resistance of the fourth cooling body 54 included in the fourth heat dissipation path can be reduced, the heat dissipation performance can be improved.

[0167] Preferably, the thickness of the fifth cooling body 55 in a direction substantially perpendicular to the surface 35a of the fifth printed circuit board 35 is increased. Thereby, since the thermal resistance of the fifth cooling body 55 included in the fifth heat dissipation path can be reduced, the heat dissipation performance can be improved.

[0168] That is, referring to Figure 31 , preferably, the thickness of each of the fourth cooling body 54 and the fifth cooling body 55 in a direction orthogonal to the direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1 is thicker than the thickness of the first cooling body 51 in the direction in which the second main surface S2 faces the first main surface S1.

[0169] In addition, in addition to the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33, high-heat-generating components can also be mounted on each of the fourth printed circuit board 34 and the fifth printed circuit board 35. Therefore, since the distance between the high-heat-generating components mounted on the printed circuit board can be extended, the thermal interference of the heat generated in each high-heat-generating component can be suppressed, and the heat dissipation performance of the power conversion device 100 with respect to the heat generated in each high-heat-generating component can be improved. As a result, the power conversion device 100 of Embodiment 3 can operate with high output.

[0170] In addition, in addition to the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33, electronic components can also be mounted on each of the fourth printed circuit board 34 and the fifth printed circuit board 35. Therefore, since the component mounting area is increased, the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 can be made smaller than in Embodiments 1 and 2. As a result, the power conversion device 100 of Embodiment 3 can be made smaller.

[0171] In addition, the electronic components on the first printed circuit board 31, the second printed circuit board 32, the third printed circuit board 33, the fourth printed circuit board 34, and the fifth printed circuit board 35 included in the power conversion device 100 of Embodiment 3 can be exchanged. For example, the power conversion device 100 of Embodiment 3 can be configured as shown in Figures 22 - 27 . Hereinafter, an example of the first printed circuit board module 71, the second printed circuit board module 72, the third printed circuit board module 73, the fourth printed circuit board module 74, and the fifth printed circuit board module 75 shown in Figures 23 - 27 will be described.

[0172] As shown in Figure 23 , switching elements 2a, 2b, 2c, and 2d are mounted on the opposite surface 31a of the first printed circuit board 31 to the surface facing the first cooling body 51. Other electronic components can be mounted on the surface 31a. Additionally, other electronic components can be mounted on the surface of the first printed circuit board 31 facing the first cooling body 51.

[0173] As shown in Figure 24 , an input capacitor 1, reactors 6, 7, and a smoothing capacitor 8 are mounted on the opposite surface 32a of the second printed circuit board 32 to the surface facing the second cooling body 52. An input terminal 9 (not shown) is mounted on the surface 32a. Other electronic components can be mounted on the surface 32a. Additionally, other electronic components can be mounted on the surface of the second printed circuit board 32 facing the second cooling body 52.

[0174] As shown in Figure 25 , transformers 3 and 4 are mounted on the opposite surface 33a of the third printed circuit board 33 to the surface facing the third cooling body 53. Other electronic components can be mounted on the surface 33a. Additionally, other electronic components can be mounted on the surface of the third printed circuit board 33 facing the third cooling body 53.

[0175] As shown in Figure 26 , rectifying elements 5a, 5b, 5c, and 5d are mounted on the opposite surface 34a of the fourth printed circuit board 34 to the surface facing the fourth cooling body 54. Other electronic components can be mounted on the surface 34a. Additionally, other electronic components can be mounted on the surface of the fourth printed circuit board 34 facing the fourth cooling body 54.

[0176] As shown in Figure 27 , rectifying elements 5e, 5f, 5g, and 5h are mounted on the opposite surface 35a of the fifth printed circuit board 35 to the surface facing the fifth cooling body 55. Other electronic components can be mounted on the surface 35a. Additionally, other electronic components can be mounted on the surface of the fifth printed circuit board 35 facing the fifth cooling body 55.

[0177] In addition, the power conversion device 100 of Embodiment 3 may not include the fifth printed circuit board 35, the fifth insulating member 45, and the fifth fixing member 65. In other words, the power conversion device 100 may include an external cooling body 21, a first printed circuit board module 71, a second printed circuit board module 72, a third printed circuit board module 73, a fourth printed circuit board module 74, and a fifth cooling body 55. The first printed circuit board module 71, the second printed circuit board module 72, the third printed circuit board module 73, and the fourth printed circuit board module 74 are electrically connected by a wiring harness or the like.

[0178] In addition, the electronic components arranged on the first printed circuit board module 71, the second printed circuit board module 72, the third printed circuit board module 73, the fourth printed circuit board module 74, and the fifth printed circuit board module 75 can be exchanged, but it is preferable to arrange particularly high-heat-generating components on the first printed circuit board module 71.

[0179] Embodiment 4.

[0180] Next, refer to Figure 28 to describe the power conversion device 100 of Embodiment 4. Unless otherwise specified, Embodiment 4 has the same structure, operation, and effects as Embodiment 2 or Embodiment 3 described above. Therefore, the same reference numerals are assigned to the same structures as those in Embodiment 2 or Embodiment 3 described above, and no repeated description is given.

[0181] The power conversion device 100 of Embodiment 4 has substantially the same structure as the power conversion device 100 of Embodiment 2 or Embodiment 3. The power conversion device 100 of Embodiment 4 is different in that a sealing member 91 is filled in the space substantially surrounded by the first cooling body 51, the second cooling body 52, the third cooling body 53, the fourth cooling body 54, and the fifth cooling body 55.

[0182] The power conversion device 100 of Embodiment 4 includes a sealing member 91. The sealing member 91 is filled in the space surrounded by the first cooling body 51, the second cooling body 52, the third cooling body 53, the fourth cooling body 54, and the fifth cooling body 55. The sealing member 91 seals the electronic components mounted on each of the first printed circuit board 31, the second printed circuit board 32, the third printed circuit board 33, the fourth printed circuit board 34, and the fifth printed circuit board 35.

[0183] The sealing member 91 may be made of a material having a thermal conductivity of 0.1 W / (m·K) or more, preferably 1.0 W / (m·K). The sealing member 91 has 1×10 10 Ω·m or more, preferably 1×10 12 Ω·m or more, more preferably 1×10 14The sealing member 91 is made of a material having a volume resistivity of Ω·m or more. In other words, the sealing member 91 has electrical insulation properties. The sealing member 91 may have a Young's modulus of 1 MPa or more. The sealing member 91 may be made of an elastic resin material. The sealing member 91 may be made of a resin material such as polyphenylene sulfide (PPS) or polyetheretherketone (PEEK) containing a heat-conductive filler. The sealing member 91 may also be made of a rubber material such as silicon or polyurethane.

[0184] Next, a method for manufacturing the power conversion device 100 according to Embodiment 5 will be described.

[0185] In Figure 10 In the preparation step S100 shown, the fourth component and the fifth component included in the electronic components, the fourth printed circuit board 34 and the fifth printed circuit board 35, the fourth cooling body 54 and the fifth cooling body 55 are prepared.

[0186] In the assembly step S200, the electronic component (fourth component) is mounted on the seventh main surface S7 of the fourth printed circuit board 34, and the fourth cooling body 54 is thermally connected to the eighth main surface S8 of the fourth printed circuit board 34 facing the seventh main surface S7. The electronic component (fifth component) is mounted on the ninth main surface S9 of the fifth printed circuit board 35, and the fifth cooling body 55 is thermally connected to the tenth main surface S10 of the fifth printed circuit board 35 facing the ninth main surface S9.

[0187] In the connection step S300, each of the fourth cooling body 54 and the fifth cooling body 55 is arranged to extend in the direction from the second main surface S2 of the first printed circuit board 31 toward the first main surface S1. The sealing member 91 is filled in the space surrounded by the first cooling body 51, the second cooling body 52, the third cooling body 53, the fourth cooling body 54, and the fifth cooling body 55.

[0188] In this way, the power conversion device 100 according to Embodiment 4 can also achieve the same effects as the power conversion devices 100 according to Embodiments 2 and 3. Moreover, in the power conversion device 100 according to Embodiment 4, as a heat dissipation path for dissipating heat generated in the circuit pattern formed on the surface or inside of the printed circuit board and heat generated in the high-heat-generating components mounted on the printed circuit board, a heat dissipation path can be formed that dissipates heat to the external cooling body 21 via the sealing member 91, the first cooling body 51, the second cooling body 52, the third cooling body 53, the fourth cooling body 54, and the fifth cooling body 55. Therefore, the heat dissipation performance of the power conversion device 100 for heat generated in the circuit pattern formed on the surface or inside of the printed circuit board and heat generated in the high-heat-generating components mounted on the printed circuit board can be improved. As a result, the power conversion device 100 can operate with a high output.

[0189] In addition, generally, in order to prevent surface discharge between electronic components, it is necessary to ensure a creepage distance corresponding to the voltage applied to each electronic component between the electronic components. In the power conversion device 100 of Embodiment 4, since a sealing member 91 having electrical insulation properties is filled between the electronic components, surface discharge is less likely to occur. Therefore, the creepage distance between the electronic components can be shortened. As a result, compared with the power conversion devices 100 of Embodiments 1 to 3, the power conversion device 100 of Embodiment 4 can miniaturize the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33. As a result, the power conversion device 100 of Embodiment 4 can be miniaturized.

[0190] In addition, when the sealing member 91 is filled between the printed circuit board and the cooling body, an insulating member disposed between the printed circuit board and the cooling body can be dispensed with. Therefore, the number of components constituting the power conversion device 100 can be reduced.

[0191] Embodiment 5.

[0192] Next, Figure 29 the power conversion device 100 of Embodiment 5 will be described. Unless otherwise specified, Embodiment 5 has the same structure, operation, and effects as those of the above-described Embodiments 1 to 4. Therefore, the same reference numerals are given to the same structures as those of the above-described Embodiments 1 to 4, and redundant description will not be repeated.

[0193] The power conversion device 100 of Embodiment 5 has substantially the same structure as the power conversion devices 100 of Embodiments 1 to 4. The power conversion device 100 of Embodiment 5 is different from the power conversion devices 100 of Embodiments 1 to 4 in that it includes a sixth printed circuit board (sixth substrate) 36, an electronic component (sixth component) mounted on the sixth printed circuit board 36, and a sixth fixing member 66.

[0194] The power conversion device 100 of Embodiment 5 includes an electronic component (sixth component) and a sixth printed circuit board (sixth substrate) on which the electronic component (sixth component) is mounted.

[0195] The sixth fixing member 66 fixes the sixth printed circuit board 36 to at least one of the second cooling body 52, the third cooling body 53, the fourth cooling body, and the fifth cooling body 55. The sixth printed circuit board 36 is fixed to at least one of the first cooling body 51, the second cooling body 52, the third cooling body 53, the fourth cooling body 54, and the fifth cooling body 55 by the sixth fixing member 66. For example, as Figure 29 shown, the sixth printed circuit board 36 can also be fixed to the second cooling body 52 and the third cooling body 53 by the sixth fixing member 66. In this case, Figure 10In the connection process S300 shown, the sixth printed circuit board 36 is fixed to the second cooling body 52 and the third cooling body 53.

[0196] On the surface 36a of the sixth printed circuit board 36 opposite to the surface facing the first cooling body 51, components included in the power conversion device 100 that are not high heat generating components are mounted, such as the input capacitor 1, the smoothing capacitor 8, the control circuit unit 15 (not shown), etc. The heat generation amount of the electronic components (sixth components) mounted on the sixth printed circuit board 36 is less than that of each of the electronic components (first components) mounted on the first printed circuit board 31, the electronic components (second components) mounted on the second printed circuit board 32, and the electronic components (third components) mounted on the third printed circuit board 33. In addition, these heat generation amounts are the heat generation amounts when the power conversion device 100 is operating. An input terminal 9 and an output terminal 10 (not shown) are mounted on the surface 36a. In addition, part or all of the electronic components mounted on the surface 36a of the sixth printed circuit board 36 may also be mounted on the surface 36b opposite to the surface 36a of the sixth printed circuit board 36.

[0197] In this way, the power conversion device 100 of Embodiment 5 can also achieve the same effects as the power conversion devices 100 of Embodiments 1 to 4. In addition, generally speaking, components that are not high heat generating components, such as the input capacitor 1, the smoothing capacitor 8, the control circuit unit 15 (not shown), etc., have a lower heat resistant temperature than high heat generating components. Therefore, when mounting high heat generating components and components that are not high heat generating components on the same printed circuit board, it is necessary to perform thermal design so that the temperature of the components that are not high heat generating components does not exceed their allowable temperature due to the heat generated in the high heat generating components. In the power conversion device 100 of Embodiment 5, since the components that are not high heat generating components are mounted on a printed circuit board different from the high heat generating components, it is not necessary to perform thermal design so that the temperature of the components that are not high heat generating components does not exceed their allowable temperature due to the heat generated in the high heat generating components.

[0198] Embodiment 6.

[0199] Next, with reference to Figure 33 and Figure 34 the power conversion device 100 of Embodiment 6 will be described. Unless otherwise specified, Embodiment 6 has the same structure, operation, and effects as Embodiment 1 described above. Therefore, the same reference numerals are assigned to the same structures as those in Embodiment 1 described above, and no repeated description will be given.

[0200] The power conversion device 100 of Embodiment 6 has substantially the same structure as the power conversion device 100 of Embodiment 1. The power conversion device 100 of Embodiment 6 is different from the power conversion device 100 of Embodiment 1 in that it includes a low resistance current path member (current path member) 88.

[0201] The low-resistance current path member 88 is formed of an arbitrary conductive material, such as copper, nickel, gold, aluminum, silver, tin, or their alloys. The low-resistance current path member 88 has a volume resistivity of 1.0×10 -6 Ω·m or less, preferably 1.0×10 -7 Ω·m or less. A part or all of the first cooling body 51, the second cooling body 52, and the third cooling body 53 form a current path (first conduction path) A-A'.

[0202] As Figure 34 shown, the low-resistance current path member 88 forms a current path (second conduction path) B that is electrically connected in parallel with the current path A-A', and the current path A-A' is constituted by a part or all of the first cooling body 51, the second cooling body 52, and the third cooling body 53.

[0203] A specific example of the current path A-A' and the current path B will be described. For example, as Figure 33 shown, the current path A-A' is constituted by the third cooling body 53, the first cooling body 51, and the second cooling body 52, and electrically connects the third printed circuit board 33 and the second printed circuit board 32. At this time, for example, as Figure 33 shown, the current path B can be constituted by the third cooling body 53, the low-resistance current path member 88, and the second cooling body 52, and is formed to electrically connect the third printed circuit board 33 and the second printed circuit board 32.

[0204] Preferably, the resistance of the current path B formed by the low-resistance current path member 88 is lower than the resistance of the current path A-A'. The material and shape of the current path B can be determined independently of the material and shape of the current path A-A' constituted by a part or all of the first cooling body 51, the second cooling body 52, and the third cooling body 53. Therefore, for example, when the current path A-A' is made of aluminum, by forming the current path B with a conductor having a smaller volume resistivity than aluminum, such as copper, the resistance of the current path B can be made smaller than the resistance of the current path A-A'. In addition, by making the path length of the current path B shorter than the path length of the current path A-A' or making the cross-sectional area of the current path B larger than the cross-sectional area of the current path A-A', the resistance of the current path B can be made smaller than the resistance of the current path A-A'.

[0205] In this way, the power conversion device 100 of Embodiment 6 can also achieve the same effect as the power conversion device 100 of Embodiment 1.

[0206] In the power conversion device 100 of Embodiment 1, when the first cooling body 51, the second cooling body 52, and the third cooling body 53 are used as Figure 32In the case of the current path A - A' shown, current flows through the first cooling body 51, the second cooling body 52, and the third cooling body 53. At this time, since Joule heat proportional to the square of the current value is generated in the first cooling body 51, the second cooling body 52, and the third cooling body 53, the temperatures of the first cooling body 51, the second cooling body 52, and the third cooling body 53 rise. As a result, since the temperatures of the high - heat - generating components mounted on the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 also rise corresponding to the temperature rises of the first cooling body 51, the second cooling body 52, and the third cooling body 53, the heat dissipation performance for the high - heat - generating components mounted on the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 of the power conversion device 100 of Embodiment 1 deteriorates.

[0207] On the other hand, in the power conversion device 100 of Embodiment 6, a current path B that is electrically connected in parallel with the current path A - A' is formed by the low - resistance current path member 88. Therefore, a part of the current flowing in the current path A - A' is shunted to the current path B. As a result, the current flowing in the current path A - A' decreases, and the Joule heat generated in the first cooling body 51, the second cooling body 52, and the third cooling body 53 decreases. As a result, in the power conversion device 100 of Embodiment 1, compared with the case where the first cooling body 51, the second cooling body 52, and the third cooling body 53 are used as, for example, Figure 32 the current path A - A' shown, the heat dissipation performance for the high - heat - generating components mounted on the first printed circuit board 31, the second printed circuit board 32, and the third printed circuit board 33 can be improved.

[0208] In addition, the smaller the resistance of the current path B formed by the low - resistance current path member 88 is compared with the resistance of the current path A - A', the larger the amount of current shunted from the current flowing in the current path A - A' to the current path B becomes. For example, when the resistance of the current path B is 1 / 2 of the resistance of the current path A - A', the amount of current flowing in the current path A - A' is reduced to 1 / 3 compared with the case where there is no current path B. Therefore, since Joule heat is proportional to the square of the current value, the heat generation of the current path A - A' is reduced to 1 / 9 compared with the case where there is no current path B.

[0209] In addition, in Figure 33 only one low - resistance current path member 88 is illustrated, but a plurality of low - resistance current path members 88 can also be combined to form a plurality of current paths B that are electrically connected in parallel with the current path A - A'.

[0210] In addition, the above - described embodiments can be appropriately combined.

[0211] The embodiments disclosed this time shall be considered illustrative only and not restrictive in all respects. The scope of the present disclosure is shown not by the above description but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0212] Description of Reference Numerals

[0213] 21 External cooling body, 31 First printed circuit board, 32 Second printed circuit board, 33 Third printed circuit board, 34 Fourth printed circuit board, 35 Fifth printed circuit board, 36 Sixth printed circuit board, 41 - 45 First insulating member - Fifth insulating member, 51 - 55 First cooling body - Fifth cooling body, 61 - 66 First fixing member - Sixth fixing member, 71 - 75 First printed circuit board module - Fifth printed circuit board module, 81 Upper core, 82 Lower core, 83 Spring, 84 Support pillar, 85 Pressing plate, 86 Wiring harness, 87 Terminal block, 88 Low-resistance current path member, 91 Sealing member, 100 Power conversion device, HC1 First heat-conductive member, HC2 Second heat-conductive member, S1 - S10 First main surface - Tenth main surface, S100 Preparation process, S200 Assembly process, S300 Connection process.

Claims

1. A power conversion device, wherein, The power conversion device includes: electronic components, which include a first component and a second component; a first substrate having a first main surface on which the first component of the electronic components is mounted and a second main surface facing the first main surface; a first cooling body thermally connected to the second main surface of the first substrate; a second substrate having a third main surface on which the second component of the electronic components is mounted and a fourth main surface facing the third main surface; and a second cooling body thermally connected to the fourth main surface of the second substrate, the first cooling body forms the bottom surface of the support body, the second cooling body forms the side surface of the support body, the second cooling body extends in a direction from the second main surface of the first substrate toward the first main surface, the second substrate is disposed on the surface of the second cooling body facing the first substrate.

2. The power conversion device according to claim 1, wherein the power conversion device further includes an external cooling body thermally connected to the first cooling body, each of the first cooling body and the second cooling body is configured as a plate, the thickness of the first cooling body in the direction in which the second main surface faces the first main surface is thinner than the thickness of the second cooling body in the direction in which the fourth main surface faces the third main surface.

3. A power conversion device, wherein, The power conversion device includes: electronic components, which include a first component, a second component, and a third component; a first substrate having a first main surface on which the first component of the electronic components is mounted and a second main surface facing the first main surface; a first cooling body thermally connected to the second main surface of the first substrate; a second substrate having a third main surface on which the second component of the electronic components is mounted and a fourth main surface facing the third main surface; a second cooling body thermally connected to the fourth main surface of the second substrate; a third substrate having a fifth main surface on which the third component of the electronic components is mounted and a sixth main surface facing the fifth main surface; and a third cooling body thermally connected to the sixth main surface of the third substrate, the second cooling body extends in a direction from the second main surface of the first substrate toward the first main surface, the third cooling body extends in a direction from the second main surface of the first substrate toward the first main surface, the second substrate and the third substrate are disposed opposite to each other.

4. The power conversion device according to claim 3, wherein the power conversion device further includes an external cooling body thermally connected to the first cooling body, each of the first cooling body, the second cooling body, and the third cooling body is configured as a plate, the thickness of the first cooling body in the direction in which the second main surface faces the first main surface is thinner than the thickness of the second cooling body in the direction in which the fourth main surface faces the third main surface and the thickness of the third cooling body in the direction in which the sixth main surface faces the fifth main surface.

5. The power conversion device according to claim 3 or 4, wherein, the power conversion device further comprises: a first insulating member disposed between the second main surface of the first substrate and the first cooling body; a second insulating member disposed between the fourth main surface of the second substrate and the second cooling body; and a third insulating member disposed between the sixth main surface of the third substrate and the third cooling body, the first cooling body is thermally connected to the second main surface of the first substrate via the first insulating member, the second cooling body is thermally connected to the fourth main surface of the second substrate via the second insulating member, the third cooling body is thermally connected to the sixth main surface of the third substrate via the third insulating member.

6. The power conversion device according to claim 3 or 4, wherein, the second cooling body is thermally connected to the first cooling body, the third cooling body is thermally connected to the first cooling body.

7. The power conversion device according to claim 6, wherein, the power conversion device further comprises a first heat conductive member, the first cooling body is thermally connected to each of the second cooling body and the third cooling body via the first heat conductive member.

8. The power conversion device according to claim 3 or 4, wherein, the power conversion device further comprises: a fourth cooling body thermally connected to the first cooling body, the second cooling body, and the third cooling body; and a fifth cooling body thermally connected to the first cooling body, the second cooling body, and the third cooling body, the fourth cooling body extends in a direction from the second main surface of the first substrate toward the first main surface, the fifth cooling body extends in a direction from the second main surface of the first substrate toward the first main surface.

9. The power conversion device according to claim 8, wherein, each of the fourth cooling body and the fifth cooling body is configured in a plate shape, the thickness of each of the fourth cooling body and the fifth cooling body in a direction orthogonal to the direction from the second main surface of the first substrate toward the first main surface is thicker than the thickness of the first cooling body in a direction in which the second main surface faces the first main surface.

10. The power conversion device according to claim 9, wherein, the power conversion device further comprises a second heat conductive member, the fourth cooling body is thermally connected to each of the first cooling body, the second cooling body, and the third cooling body via the second heat conductive member, the fifth cooling body is thermally connected to each of the first cooling body, the second cooling body, and the third cooling body via the second heat conductive member.

11. The power conversion device according to claim 8, wherein, the electronic component includes a fourth component, the power conversion device further comprises: a fourth substrate having a seventh main surface on which the fourth component of the electronic component is mounted and an eighth main surface facing the seventh main surface; and A fourth insulating member, the fourth insulating member being disposed between the eighth main surface of the fourth substrate and the fourth cooling body, the fourth cooling body being thermally connected to the eighth main surface of the fourth substrate via the fourth insulating member.

12. The power conversion device according to claim 8, wherein, the electronic component includes a fifth component, the power conversion device further includes: a fifth substrate having a ninth main surface on which the fifth component of the electronic component is mounted and a tenth main surface facing the ninth main surface; and a fifth insulating member disposed between the tenth main surface of the fifth substrate and the fifth cooling body, the fifth cooling body being thermally connected to the tenth main surface of the fifth substrate via the fifth insulating member.

13. The power conversion device according to claim 8, wherein, the power conversion device further includes a sealing member, the sealing member being filled in a space surrounded by the first cooling body, the second cooling body, the third cooling body, the fourth cooling body, and the fifth cooling body.

14. The power conversion device according to claim 13, wherein, The sealing member has a volume resistivity of 1×10 10 Ω·m or more.

15. The power conversion device according to claim 3 or 4, wherein, the electronic component includes a sixth component, the power conversion device further includes a sixth substrate on which the sixth component of the electronic component is mounted, the heat generation amount of the sixth component being less than the heat generation amount of each of the first component, the second component, and the third component.

16. The power conversion device according to claim 3 or 4, wherein, the power conversion device further includes a current path member, a part or all of the first cooling body, the second cooling body, and the third cooling body form a first conduction path, the current path member forms a second conduction path electrically connected in parallel with the first conduction path.

17. The power conversion device according to claim 16, wherein, the resistance value of the second conduction path is lower than the resistance value of the first conduction path.

18. A manufacturing method of a power conversion device, wherein, The manufacturing method of the power conversion device includes: a preparation step in which a first substrate, a second substrate, and a third substrate, a first cooling body, a second cooling body, and a third cooling body, and an electronic component including a first component, a second component, and a third component are prepared; an assembly step in which, in the assembly step, the first component of the electronic component is mounted on the first main surface of the first substrate and the first cooling body is thermally connected to the second main surface of the first substrate facing the first main surface, the second component of the electronic component is mounted on the third main surface of the second substrate and the second cooling body is thermally connected to the fourth main surface of the second substrate facing the third main surface, the third component of the electronic component is mounted on the fifth main surface of the third substrate and the third cooling body is thermally connected to the sixth main surface of the third substrate facing the fifth main surface, the second substrate and the third substrate are arranged facing each other, and the first substrate, the second substrate, and the third substrate are electrically connected; and Connecting step, in which the second cooling body and the third cooling body are fixed to the first cooling body in such a manner that each of the second cooling body and the third cooling body is configured to extend in a direction from the second main surface of the first substrate toward the first main surface.

19. The method for manufacturing a power conversion device according to claim 18, wherein, in the connecting step, the second cooling body and the third cooling body are thermally connected to the first cooling body.

20. The method for manufacturing a power conversion device according to claim 18 or 19, wherein, in the assembling step, each of the second component and the third component is fixed to a groove provided in each of the second substrate and the third substrate.

21. The method for manufacturing a power conversion device according to claim 18 or 19, wherein, in the preparation step, a fourth substrate and a fifth substrate, a fourth cooling body and a fifth cooling body, a fourth component and a fifth component included in the electronic component are prepared, in the assembling step, the fourth component of the electronic component is mounted on the seventh main surface of the fourth substrate and the fourth cooling body is thermally connected to the eighth main surface of the fourth substrate facing the seventh main surface, the fifth component of the electronic component is mounted on the ninth main surface of the fifth substrate and the fifth cooling body is thermally connected to the tenth main surface of the fifth substrate facing the ninth main surface, and the first substrate, the second substrate, the third substrate, the fourth substrate and the fifth substrate are electrically connected, in the connecting step, each of the fourth cooling body and the fifth cooling body is configured to extend in a direction from the second main surface of the first substrate toward the first main surface, and a sealing member is filled in the space surrounded by the first cooling body, the second cooling body, the third cooling body, the fourth cooling body and the fifth cooling body.

22. The method for manufacturing a power conversion device according to claim 18 or 19, wherein, in the preparation step, a sixth substrate and a sixth component included in the electronic component are prepared, in the connecting step, the sixth substrate is fixed to the second cooling body and the third cooling body.

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