Power conversion device and motor module

Abstract

The present invention is provided with: a capacitor module having a capacitor element and a case part that accommodates the capacitor element; a power module having a power semiconductor element that performs power conversion; a control substrate driving the power module; and a bus bar module having a bus bar. The capacitor element has a capacitor body portion and a first connection terminal extending from the capacitor body portion toward one side in a first direction. The power module has a second connection terminal. The bus bar electrically connects the first connection terminal and the second connection terminal. The housing part has: a first accommodating part which is recessed from one side of the first direction to the other side of the first direction and accommodates the capacitor main body part; and a first flow path through which a refrigerant flows.

Description

Technical Field

[0001] This invention relates to power conversion devices and motor modules. Background Technology

[0002] As an example of an electric power conversion device for supplying power to a motor, an electric power conversion device is disclosed, comprising: a power module unit having a power semiconductor; a capacitor unit having a capacitor element; and a refrigerant flow path for supplying refrigerant to cool the capacitor element, wherein the power module unit and the capacitor element are electrically connected via a busbar (e.g., Japanese Patent Application Publication No. 2013-031330).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Publication No.: Japanese Patent Application Publication No. 2013-031330 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In the power conversion device described in Patent Document 1, because a busbar is arranged between the capacitor element and the refrigerant flow path, the thermal resistance between the capacitor element and the refrigerant flow path tends to increase. Therefore, it is difficult to increase the amount of heat transferred from the capacitor element to the refrigerant flowing in the refrigerant flow path, and the temperature of the capacitor element may become excessively high. This may accelerate the deterioration of the capacitor element.

[0008] In view of the above circumstances, one objective of this invention is to provide a power conversion device and motor module that can suppress the temperature of capacitor elements from becoming too high.

[0009] Solution for solving the problem

[0010] One embodiment of the power conversion device of the present invention includes: a capacitor module having a capacitor element and a housing portion for accommodating the capacitor element; a power module having a power semiconductor element for performing power conversion; a control board for driving the power semiconductor element; and a busbar module having a busbar. The capacitor element has a capacitor body portion and a first connection terminal extending from the capacitor body portion in a first direction. The power module has a second connection terminal. The busbar electrically connects the first connection terminal and the second connection terminal. The housing portion has: a first receiving portion recessed from one side in the first direction to the other side in the first direction to accommodate the capacitor body portion; and a first flow path for refrigerant flow.

[0011] One embodiment of the motor module of the present invention includes: the power conversion device described above; and a motor driven by current supplied from the power conversion device.

[0012] Invention Effects

[0013] According to one aspect of the present invention, in power conversion devices and motor modules, it is possible to suppress the temperature of capacitor elements from becoming too high. Attached Figure Description

[0014] Figure 1 This is a perspective view of the motor module according to the first embodiment.

[0015] Figure 2 This is a perspective view showing a portion of the motor module according to the first embodiment.

[0016] Figure 3 This is a cross-sectional view showing a portion of the power conversion device according to the first embodiment.

[0017] Figure 4 This is a cross-sectional view showing a portion of the power conversion device according to the first embodiment. Figure 3 Sectional view IV-IV.

[0018] Figure 5 This is a cross-sectional view showing a portion of the power conversion device according to the second embodiment. Detailed Implementation

[0019] Hereinafter, a power conversion device according to an embodiment of the present invention will be described with reference to the accompanying drawings. It should be noted that the scope of the present invention is not limited to the following embodiments, and modifications can be made arbitrarily within the scope of the technical concept of the present invention. Furthermore, in the following drawings, for ease of understanding of the various components, the actual structure may sometimes differ from the scale, quantities, etc.

[0020] <First Implementation>

[0021] In the following description, the first direction D1 is appropriately shown in the figures. In this embodiment, the first direction D1 is the vertical direction of the power conversion device 10. In the following description, the side in which the arrow of the first direction D1 points (+D1 side) is referred to as "one side of the first direction D1" or "upper side". The side opposite to the side in which the arrow of the first direction D1 points (-D1 side) is referred to as "the other side of the first direction D1" or "lower side".

[0022] In the following description, the second direction D2 is appropriately shown in the figures. In this embodiment, the second direction D2 is the left-right direction of the power conversion device 10. The second direction D2 intersects the first direction D1. In this embodiment, the second direction D2 is orthogonal to the first direction D1. In the following description, the side in which the arrow of the second direction D2 points (+D2 side) is referred to as the "left side". The side opposite to the side in which the arrow of the second direction D2 points (-D2 side) is referred to as the "right side".

[0023] In the following description, the third direction D3 is appropriately shown in each figure. The third direction D3 is a direction orthogonal to both the first direction D1 and the second direction D2. The third direction D3 is the front-rear direction of the power conversion device 10. In the following description, the side in which the arrow of the third direction D3 points (+D3 side) is referred to as the "front side". The side opposite to the side in which the arrow of the third direction D3 points (-D3 side) is referred to as the "rear side".

[0024] It should be noted that the terms "upper side," "lower side," "left side," "right side," "front side," and "rear side" are merely names used to describe the relative positional relationships of the various parts. The actual configuration relationships may also be those other than those indicated by these names.

[0025] Figure 1 This is a perspective view showing the motor module 90 of this embodiment. The motor module 90 includes a power conversion device 10 and a motor 91. The motor 91 is, for example, a drive device mounted on a vehicle and rotating the vehicle's axle. The motor 91 is driven by current supplied from the power conversion device 10. Vehicles equipped with the motor module 90 are hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHVs), electric vehicles (EVs), and other vehicles that use the motor 91 as a power source.

[0026] The power conversion device 10 supplies current to the motor 91. The power conversion device 10 generates the current supplied to the motor 91 and supplies current to the U-phase coil, V-phase coil, and W-phase coil of the motor 91 respectively. Figure 2 As shown, the power conversion device 10 includes a housing 11, a holding part 21, a power module 24, a control board 25, a busbar module 30, a capacitor module 40, and a refrigerant flow path 60.

[0027] The outer casing 11 internally houses the retaining part 21, power module 24, control board 25, busbar module 30, capacitor module 40, and other components constituting the power conversion device 10. Figure 1As shown, the outer casing 11 is a generally rectangular box shape. When viewed from the first direction D1, the outer casing 11 is a generally rectangular shape with its long side extending along the second direction D2. The outer casing 11 has a first outer casing 12 and a second outer casing 13.

[0028] like Figure 2 As shown, the first outer casing 12 is box-shaped with an opening on the upper side (-D3 side). The first outer casing 12 has a peripheral wall portion 12a and a bottom wall portion 12b. Figure 1 As shown, the peripheral wall portion 12a is a square cylindrical shape protruding in the first direction D1. The peripheral wall portion 12a surrounds the retaining portion 21, the power module 24, the control board 25, the busbar module 30, and the capacitor module 40 in the second direction D2 and the third direction D3. The wall portion of the peripheral wall portion 12a located on the front side (+D3 side) and extending along the second direction D2 is provided with a first conduit 61 and a fourth conduit 66 extending along the third direction D3.

[0029] The first pipe 61 is positioned to the right (-D2 side) of the fourth pipe 66. The front (+D3 side) portions of both the first pipe 61 and the fourth pipe 66 protrude forward beyond the peripheral wall portion 12a. A supply pipe 71 is connected to the front end of the first pipe 61. A discharge pipe 72 is connected to the front end of the fourth pipe 66. Figure 2 As shown, the rear (-D3 side) portions of both the first pipe 61 and the fourth pipe 66 protrude rearward beyond the peripheral wall portion 12a. Although not shown in the figure, the rear end of the first pipe 61 is connected to the capacitor module 40. The rear end of the fourth pipe 66 is connected to the retaining portion 21. Refrigerant L flows inside the first pipe 61 and the fourth pipe 66.

[0030] The bottom wall portion 12b is a plate-shaped portion extending in a direction orthogonal to the first direction D1. The plate surface of the bottom wall portion 12b faces the first direction D1. The outer edge of the bottom wall portion 12b is connected to the lower end of the peripheral wall portion 12a.

[0031] Figure 1 The second outer casing 13 shown is box-shaped with an opening on the downward side (-D1 side). The second outer casing 13 is fixed to the upper end of the first outer casing 12.

[0032] like Figure 3 As shown, the holding part 21 holds the power module 24. The holding part 21 is positioned lower than the power module 24 (-D1 side). The power module 24 is fixed to the upper end of the holding part 21. The holding part 21 has a holding housing 22 and a heat sink 23.

[0033] like Figure 4 As shown, the housing 22 maintains a generally cuboid shape extending along the third direction D3. (As indicated...) Figure 3As shown, two surfaces of the retaining housing 22 face the first direction D1, and the other two surfaces of the retaining housing 22 face the second direction D2. The retaining housing 22 is provided with a first recess 22a, a second recess 22b, a third hole 22c, and a fourth hole 22d.

[0034] The first recess 22a is recessed downward from the surface of the retaining housing 22 that faces upward (+D1 side). For example... Figure 4 As shown, when viewed from the first direction D1, the first recess 22a is approximately rectangular. Figure 3 As shown, the second recess 22b is recessed downward from the upward-facing surface of the retaining housing 22. Although not shown in the figure, when viewed from the first direction D1, the second recess 22b is a generally quadrilateral ring with its long side extending along the third direction D3. The second recess 22b surrounds the first recess 22a from the outer sides of both the second direction D2 and the third direction D3.

[0035] like Figure 4 As shown, the third hole 22c is a hole that penetrates the wall portion of the retaining housing 22 in the third direction D3, located on the rear side (-D3 side) and extending in the second direction D2. The exterior of the retaining housing 22 is connected to the interior of the first recess 22a via the third hole 22c. A third conduit 64 is connected to the third hole 22c. The fourth hole 22d is a hole that penetrates the wall portion of the retaining housing 22 in the third direction D3, located on the front side (+D3 side) and extending in the second direction D2. The exterior of the retaining housing 22 is connected to the interior of the first recess 22a via the fourth hole 22d. A fourth conduit 66 is connected to the fourth hole 22d.

[0036] Figure 3 The heat sink 23 shown transfers heat generated in the power module 24 to the refrigerant L flowing inside the first recess 22a of the retaining housing 22. In this embodiment, the heat sink 23 is made of a metallic material such as copper and aluminum. The heat sink 23 has a main body 23a, a fixing part 23b, and a plurality of finned parts 23c.

[0037] The main body 23a is a plate-shaped portion extending in a direction orthogonal to the first direction D1. The plate surface of the main body 23a faces the first direction D1. The main body 23a blocks the first recess 22a from the upper side (+D1 side). The power module 24 is fixed to the upper-facing surface of the main body 23a. Thus, the holding part 21 holds the power module 24.

[0038] The fixing part 23b protrudes downward from the outer edge of the main body part 23a. Although not shown in the figure, when viewed from the first direction D1, the fixing part 23b is a roughly quadrilateral ring with its long side extending along the third direction D3. The fixing part 23b is disposed inside the second recess 22b. The fixing part 23b is fixed to the inner surface of the second recess 22b. Thus, the heat sink 23 is fixed to the retaining housing 22. A sealing member 81 is disposed between the inner peripheral surface of the fixing part 23b and the inner surface of the second recess 22b. The sealing member 81 contacts both the inner peripheral surface of the fixing part 23b and the inner surface of the second recess 22b. Thus, the sealing member 81 seals the heat sink 23 and the retaining housing 22.

[0039] Multiple finned portions 23c protrude downwards from the main body portion 23a. Each finned portion 23c is disposed inside the first recess 22a. For example... Figure 4 As shown, in this embodiment, each fin portion 23c is arranged spaced apart from each other along both the second direction D2 and the third direction D3. Alternatively, each fin portion 23c may be arranged spaced apart from each other only along either the second direction D2 or the third direction D3. Figure 3 As shown, in this embodiment, each fin portion 23c is arranged at a distance from the upward-facing (+D1 side) surface of the first recess 22a in the first direction D1. Each fin portion 23c may also contact the upward-facing surface of the first recess 22a. It should be noted that the heat sink 23 may also not have fin portions 23c.

[0040] The holding part 21 is provided with a second flow path 65 for the refrigerant L to flow. The second flow path 65 is formed by the inner surface of the first recess 22a, the downward-facing surface of the main body 23a, and the outer surface of each fin portion 23c. Each fin portion 23c protrudes into the interior of the second flow path 65. Each fin portion 23c is in contact with the refrigerant L flowing in the second flow path 65.

[0041] The power module 24 generates a current of a predetermined waveform based on the current supplied by an external power source (not shown) and supplies this current to the motor 91. More specifically, the power conversion device 10 generates phase currents (U-phase current, V-phase current, and W-phase current) that are respectively supplied to the U-phase coil, V-phase coil, and W-phase coil of the motor 91. In this embodiment, the power conversion device 10 is an inverter that converts direct current to alternating current. The power module 24 has a power semiconductor element 24c and a second connection terminal 26.

[0042] Power semiconductor element 24c generates a current of a predetermined waveform based on the current supplied by an external power source (not shown). Thus, power semiconductor element 24c performs power conversion. In this embodiment, as an example, power semiconductor element 24c converts direct current to alternating current. In this embodiment, power semiconductor element 24c is, for example, an electronic component such as a metal-oxide-semiconductor field-effect transistor (MOSFET) and an insulated-gate bipolar transistor (IGBT). Power module 24 has multiple power semiconductor elements 24c. Although not shown, in this embodiment, power module 24 has six power semiconductor elements 24c. Each pair of power semiconductor elements 24c generates one of the following phase currents: U-phase current, V-phase current, and W-phase current.

[0043] The second connection terminal 26 electrically connects the power semiconductor element 24c disposed inside the power module 24 to the busbar module 30. The second connection terminal 26 is a plate-shaped protrusion extending to the right side (-D2 side) of the power module 24. The plate surface of the second connection terminal 26 faces the first direction D1. The second connection terminal 26 is made of metal. In this embodiment, the power module 24 has six second connection terminals 26. The six second connection terminals 26 include three second positive terminals 26a and three second negative terminals 26b.

[0044] Each second positive terminal 26a is arranged spaced apart from the other in the third direction D3. Each second positive terminal 26a is electrically connected to a pair of different power semiconductor elements 24c. The second negative terminals 26b are also arranged spaced apart from the other in the third direction D3. When viewed from the first direction D1, each second negative terminal 26b is positioned offset from the second positive terminals 26a in the third direction D3. Figure 3 As shown, each second negative terminal 26b is positioned above (on the +D1 side) each second positive terminal 26a. Each second negative terminal 26b is electrically connected to a pair of different power semiconductor elements 24c.

[0045] Figure 2The output terminal 95 shown is the path for the current generated by the power semiconductor element 24c to flow. The output terminal 95 is a plate-shaped protrusion extending to the left (+D2 side) from the power module 24. The output terminal 95 is made of metal. Although not shown in the figure, the right end (+D2 side) of the output terminal 95 is electrically connected to the power semiconductor element 24c of the power module 24. Furthermore, a terminal connected to the coil of the motor 91 is connected to the left end of the output terminal 95. Thus, phase current is supplied from the power module 24 to the coil of the motor 91. In this embodiment, the power module 24 has three output terminals 95. Each output terminal 95 is arranged in the third direction D3. Any one of the following currents flows in each output terminal 95: U-phase current, V-phase current, and W-phase current.

[0046] The control substrate 25 is a printed mounting substrate extending in a direction orthogonal to the first direction D1. Viewed from the first direction D1, the control substrate 25 has a generally rectangular shape with its long side extending along the third direction D3. The control substrate 25 drives power semiconductor elements 24c. Although not shown in the figure, multiple electronic components such as ICs (Integrated Circuits) and resistors are mounted on the control substrate 25. Figure 3 As shown, the control board 25 is positioned above the heat sink 23 (on the +D1 side). The control board 25 is supported by a plurality of connecting pins 24d in a first direction D1. Each connecting pin 24d is conductive. Each connecting pin 24d electrically connects the power module 24 to the control board 25. Thus, each power semiconductor element 24c is electrically connected to the control board 25. The control board 25 controls the power conversion of the power module 24 by applying control pulses to each power semiconductor element 24c.

[0047] In this embodiment, the busbar module 30 is positioned to the right (-D2 side) of the power specific module 24 and above the capacitor module 40 (+D1 side). The busbar module 30 has a first holding member 31 and a plurality of busbars 33.

[0048] Although not shown in the diagram, the first retaining member 31 is a generally cuboid shape extending along a third direction D3. Two faces of the first retaining member 31 face the first direction D1, and the other two faces face the second direction D2. In this embodiment, the first retaining member 31 is made of resin and has insulating properties. In this embodiment, the first retaining member 31 is formed by embedding multiple busbars 33 as embedded members. Thus, the first retaining member 31 retains each busbar 33. The first retaining member 31 is provided with a first through hole 31a and a second through hole 31b.

[0049] The first through hole 31a and the second through hole 31b are holes that penetrate the first retaining member 31 along the first direction D1. The first through hole 31a is located to the left (+D2 side) of the second through hole 31b. Figure 2 As shown, when viewed from the first direction D1, the first through hole 31a is generally rectangular. In this embodiment, the first retaining member 31 is provided with three first through holes 31a. Each first through hole 31a is spaced apart from each other along the third direction D3. When viewed from the first direction D1, the second through hole 31b is generally rectangular. In this embodiment, the first retaining member 31 is provided with three second through holes 31b. Each second through hole 31b is spaced apart from each other along the third direction D3. When viewed from the second direction D2, each second through hole 31b is located at a position offset from the first through hole 31a in the third direction D3.

[0050] like Figure 3 As shown, multiple busbars 33 electrically connect the power module 24 to the capacitor module 40. Each busbar 33 is a plate-shaped component. The multiple busbars 33 include a first busbar 34 and a second busbar 35.

[0051] The first busbar 34 has a first main body portion 34a and a first protrusion 34b. The first main body portion 34a is held on the upward-facing (+D1 side) surface of the first retaining member 31. Figure 2 As shown, the first main body 34a is a plate-shaped portion extending in a direction orthogonal to the first direction D1. The front end (+D3 side) of the first main body 34a is located further forward than the second connecting terminal 26 disposed at the foremost side, and is electrically connected to the cathode side of an external power supply (not shown). Figure 3 As shown, the left side (+D2 side) of the first main body 34a is fixed to each of the second negative terminals 26b by bolts 82. Thus, the first busbar 34 is electrically connected to each of the second negative terminals 26b. A hole 34d is provided in the first main body 34a.

[0052] Hole 34d is a hole that penetrates the first main body portion 34a along the first direction D1. For example... Figure 2 As shown, when viewed from the first direction D1, the hole portion 34d is approximately rectangular. In this embodiment, three holes 34d are provided in the first main body portion 34a. Each hole portion 34d is spaced apart from each other along the third direction D3. When viewed from the first direction D1, each hole portion 34d surrounds a different first through hole 31a.

[0053] like Figure 3 As shown, the first protrusion 34b is a plate-shaped portion protruding upward from the right side (-D2 side) of the first main body portion 34a towards the upper side (+D1 side). The plate surface of the first protrusion 34b faces the second direction D2. Figure 2As shown, the first busbar 34 has three first protrusions 34b. Each first protrusion 34b is arranged at intervals along the third direction D3.

[0054] like Figure 3 As shown, the second busbar 35 has a second main body portion 35a and a second protrusion 35b. The second main body portion 35a passes through the interior of the first retaining member 31 in the second direction D2. The second main body portion 35a is plate-shaped and extends in a direction orthogonal to the first direction D1. Although not shown in the figure, the front end (+D3 side) of the second main body portion 35a is located further forward than the second connecting terminal 26 disposed at the foremost side, and is electrically connected to the positive side of an external power source (not shown). The left side (+D2 side) of the second main body portion 35a is fixed to each of the second positive terminals 26a by bolts 82. Thus, the second busbar 35 is electrically connected to each of the second positive terminals 26a. As described above, the first busbar 34 is electrically connected to each of the second negative terminals 26b. Thus, the busbar 33 is electrically connected to the second connecting terminal 26.

[0055] The second protrusion 35b is a plate-shaped portion that protrudes upward from the right side (-D2 side) end of the second main body portion 35a to the upper side (+D1 side). The plate surface of the second protrusion 35b faces the second direction D2. Figure 2 As shown, the second busbar 35 has three second protrusions 35b. Each second protrusion 35b is spaced apart from the others along a third direction D3. Figure 3 As shown, each second protrusion 35b passes through a different first through hole 31a and hole portion 34d in the first direction D1. The upper end of each second protrusion 35b is located above the first main body portion 34a.

[0056] In this embodiment, the capacitor module 40 is positioned lower than the busbar module 30 (-D1 side). The capacitor module 40 has a housing portion 41 and a capacitor element 50. The housing portion 41 internally houses the capacitor element 50. The housing portion 41 has a first housing portion 42, a second housing portion 45, and a first flow path 62.

[0057] like Figure 4 As shown, the first housing portion 42 is a generally cuboid shape extending along the third direction D3. Figure 3 As shown, two surfaces of the first housing portion 42 face the first direction D1, and the other two surfaces of the first housing portion 42 face the second direction D2. In this embodiment, the first housing portion 42 is made of metal. The first housing portion 42 is provided with a first receiving portion 42a and a plurality of protrusions 42c.

[0058] The first receiving portion 42a is recessed from the upper side of the first housing portion 42, that is, the side facing the first direction D1 (+D1 side), to the lower side, that is, the other side of the first direction D1 (-D1 side). Figure 4 As shown, when viewed from the first direction D1, the first receiving portion 42a is approximately rectangular in shape with its long side extending along the third direction D3. In this embodiment, three first receiving portions 42a are provided in the first housing portion 42. Each first receiving portion 42a is provided at intervals along the third direction D3.

[0059] like Figure 3 As shown, multiple protrusions 42c protrude downwards from the first housing portion 42. In this embodiment, the protrusions 42c are heat dissipation fins. Although not shown in the figure, in this embodiment, each protrusion 42c is arranged spaced apart from each other along both the second direction D2 and the third direction D3. Alternatively, each protrusion 42c may be arranged spaced apart from each other only along either the second direction D2 or the third direction D3. Each protrusion 42c protrudes into the interior of the first flow path 62. It should be noted that the protrusions 42c may not be provided in the first housing portion 42.

[0060] like Figure 4 As shown, the second housing portion 45 is a generally cuboid shape extending along the third direction D3. Figure 3 As shown, two surfaces of the second housing portion 45 face the first direction D1, and the other two surfaces of the second housing portion 45 face the second direction D2. The second housing portion 45 is provided with a second receiving portion 45a, a first hole portion 45e, and a second hole portion 45f.

[0061] The second receiving portion 45a is a recessed portion that is recessed from the upper side (+D1 side) of the second housing portion 45 to the lower side (-D1 side). For example... Figure 4 As shown, when viewed from the first direction D1, the second receiving portion 45a has a generally rectangular shape with its long side extending along the third direction D3. Figure 3 As shown, a first housing portion 42 is housed inside the second receiving portion 45a. The lower end of the second receiving portion 45a is located below the lower end of the first housing portion 42. In this embodiment, the second housing portion 45 is made of resin. In this embodiment, the second housing portion 45 is formed by inserting the first housing portion 42 as an insert member. Thus, the first housing portion 42 is fixed to the inner surface of the second receiving portion 45a.

[0062] like Figure 4 As shown, the first hole 45e is a hole in the wall portion of the second housing portion 45 disposed on the front side (+D3 side) and extending in the second direction D2, penetrating the wall portion of the second housing portion 45 in the third direction D3. Figure 3 As shown, the first hole 45e is located lower than the first housing portion 42 (on the -D1 side). Figure 4 As shown, a first pipe 61 is connected to the first hole 45e.

[0063] The second hole 45f is a hole in the wall portion of the second housing portion 45 that is disposed on the rear side (-D3 side) and extends in the second direction D2, penetrating the wall portion in the third direction D3. For example... Figure 3 As shown, the second hole 45f is located lower than the first housing portion 42 (on the -D1 side). Figure 4 As shown, a second pipe 63 is connected to the second hole 45f.

[0064] The first flow path 62 is the flow path for refrigerant L. For example... Figure 3 As shown, the first flow path 62 is formed by the outer surface of the first housing portion 42 and the inner surface of the second receiving portion 45a. The first flow path 62 is connected to the outside of the second housing portion 45 via the first hole portion 45e. The first flow path 62 is connected to the outside of the second housing portion 45 via the second hole portion 45f.

[0065] Capacitor element 50 acts as a smoothing capacitor to smooth the current supplied to power module 24 from an external power source (not shown). For example... Figure 4 As shown, in this embodiment, the capacitor module 40 has a plurality of capacitor elements 50. In this embodiment, the capacitor module 40 has three capacitor elements 50. The number of capacitor elements 50 in the capacitor module 40 may be two or less, or it may be four or more. Figure 3 As shown, each capacitor element 50 has a capacitor body portion 51 and a first connection terminal 52.

[0066] The capacitor body 51 is generally rectangular parallelepiped in shape. For example... Figure 3 and Figure 4 As shown, each capacitor body portion 51 is housed within a different first receiving portion 42a. In this embodiment, each capacitor element 50 is arranged spaced apart from each other along the direction (third direction D3) extending from the first flow path 62. Each capacitor body portion 51 is fixed to the inner surface of the first receiving portion 42a. Thus, the housing portion 41 holds a plurality of capacitor elements 50. The outer surface of each capacitor body portion 51 is made of, for example, an insulating material such as resin. Thus, the outer surface of each capacitor body portion 51 is insulating.

[0067] like Figure 3As shown, the first connection terminal 52 electrically connects the capacitor body 51 to the busbar 33. The first connection terminal 52 extends upward from the capacitor body 51, i.e., on the side of the first direction D1 (+D1 side). The first connection terminal 52 is conductive. In this embodiment, each capacitor element 50 has two first connection terminals 52. The two first connection terminals 52 include a first positive terminal 52a and a first negative terminal 52b.

[0068] Each capacitor element 50 has a first positive terminal 52a that passes through a different first through hole 31a in the first direction D1. Each first positive terminal 52a is fixed to a different second protrusion 35b of the second busbar 35. Thus, each capacitor element 50 is electrically connected to the second busbar 35. The first negative terminal 52b is positioned to the right (-D3 side) of the first positive terminal 52a. Each capacitor element 50 has a first negative terminal 52b that passes through a different second through hole 31b in the first direction D1. Each first negative terminal 52b is fixed to a different first protrusion 34b of the second busbar 35. Thus, each capacitor element 50 is electrically connected to the first busbar 34. As described above, each capacitor element 50 is electrically connected to the second busbar 35. Thus, the busbar 33 is electrically connected to the first connection terminal 52 of each capacitor element 50. Furthermore, as described above, the busbar 33 is electrically connected to the second connection terminal 26. Therefore, the busbar 33 electrically connects the first connecting terminal 52 and the second connecting terminal 26. It should be noted that in this embodiment, the first connecting terminal 52 and the busbar 33 are fixed by welding. Alternatively, the first connecting terminal 52 and the busbar 33 can be fixed by bolts or other fastening components.

[0069] Figure 4 The refrigerant flow path 60 shown is a flow path that supplies refrigerant L to the first flow path 62 and the second flow path 65. A pump (not shown) and a cooler are provided in the refrigerant flow path 60. The pump pumps the refrigerant L. The cooler cools the refrigerant L. In this embodiment, the refrigerant L is, for example, a liquid such as water or oil. The refrigerant flow path 60 has a first pipe 61, a first flow path 62, a second pipe 63, a third pipe 64, a second flow path 65, and a fourth pipe 66. In this embodiment, the first pipe 61, the second pipe 63, the third pipe 64, and the fourth pipe 66 are pipes. In this embodiment, the refrigerant L flows in the order of the first pipe 61, the first flow path 62, the second pipe 63, the third pipe 64, the second flow path 65, and the fourth pipe 66. The refrigerant L may also flow in the order of the fourth pipe 66, the second flow path 65, the third pipe 64, the second pipe 63, the first flow path 62, and the first pipe 61.

[0070] The first conduit 61 is fixed to the first orifice 45e. Thus, the first conduit 61 is connected to the first flow path 62 via the first orifice 45e. The first flow path 62 connects the first conduit 61 to the second conduit 63. In the first flow path 62, refrigerant L flows from the front side (+D3 side) to the rear side (-D3 side). Figure 3 As shown, each protrusion 42c of the first housing portion 42 protrudes into the interior of the first flow path 62. Each protrusion 42c contacts the refrigerant L flowing in the first flow path 62. This increases the contact area between the refrigerant L flowing in the first flow path 62 and the first housing portion 42.

[0071] like Figure 4 As shown, the second conduit 63 connects the first flow path 62 to the third conduit 64. One end of the second conduit 63 is fixed to the second hole 45f. Thus, the second conduit 63 is connected to the first flow path 62 via the second hole 45f. The other end of the second conduit 63 is connected to one end of the third conduit 64. The third conduit 64 connects the second conduit 63 to the second flow path 65. The other end of the third conduit 64 is fixed to the third hole 22c. Thus, the third conduit 64 is connected to the second flow path 65 via the third hole 22c.

[0072] The second flow path 65 connects the third pipe 64 and the fourth pipe 66. In the second flow path 65, the refrigerant L flows from the rear side (-D3 side) towards the front side (+D3 side). As described above, the plurality of fins 23c of the radiator 23 protrude into the interior of the second flow path 65. Each fin 23c contacts the refrigerant L flowing in the second flow path 65. This increases the contact area between the refrigerant L flowing in the second flow path 65 and the radiator 23. The fourth pipe 66 is fixed to the fourth hole 22d. Thus, the fourth pipe 66 is connected to the second flow path 65. The refrigerant L flowing from the second flow path 65 into the fourth pipe 66 is discharged to the outside of the power conversion device 10.

[0073] According to this embodiment, the power conversion device 10 includes: a capacitor module 40 having a capacitor element 50 and a housing portion 41 for accommodating the capacitor element 50; a power module 24 having a power semiconductor element 24c for power conversion; a control board 25 for driving the power module 24; and a busbar module 30 having a busbar 33. The capacitor element 50 has a capacitor body portion 51 and a first connection terminal 52 extending upward from the capacitor body portion 51 to one side (+D1 side) in the first direction D1. The power module 24 has a second connection terminal 26, and the busbar 33 electrically connects the first connection terminal 52 and the second connection terminal 26. The housing portion 41 has: a first receiving portion 42a recessed from the upper side to the lower side (-D1 side) in the first direction D1 to accommodate the capacitor body portion 51; and a first flow path 62 for supplying refrigerant L. Therefore, since the housing portion 41 accommodating the capacitor body portion 51 has a first flow path 62, the thermal resistance between the capacitor element 50 and the first flow path 62 can be reduced compared to the case where the first flow path 62 is provided in a different component than the housing portion 41. This increases the amount of heat transferred from the capacitor element 50 to the refrigerant L flowing in the first flow path 62. Consequently, it prevents the temperature of the capacitor element 50 from becoming excessively high. Therefore, it suppresses the deterioration of the capacitor element 50.

[0074] Furthermore, in this embodiment, since the first flow path 62 is provided in the housing portion 41, the shape and structure of the housing 11 can be simplified compared to the case where the first flow path 62 is provided in the outer casing 11. This helps to suppress the increase in manufacturing cost of the housing 11. Therefore, it helps to suppress the increase in manufacturing cost of the power conversion device 10.

[0075] For example, when capacitor element 50 is electrically connected to busbar 33 and then integrated into a single unit via insert molding, the manufacturing time of the integrated unit tends to increase due to the increased number of embedded components. In contrast, in this embodiment, capacitor element 50 can be electrically connected to busbar 33 after capacitor module 40 and busbar module 30 are manufactured separately. Therefore, the number of embedded components in each module 30, 40 can be easily reduced. Consequently, the increase in manufacturing time for each module 30, 40 can be easily suppressed, thus suppressing the increase in manufacturing time for power conversion device 10.

[0076] Furthermore, in this embodiment, the capacitor module 40, the busbar module 30, and the power module 24 can be manufactured in parallel during the manufacturing process of the power conversion device 10, thus making it easier to more appropriately suppress the increase in manufacturing time of the power conversion device 10.

[0077] According to this embodiment, the housing portion 41 has a first housing portion 42 for receiving a first receiving portion 42a and a second housing portion 45 for receiving a second receiving portion 45a of the first housing portion 42. The first flow path 62 is formed by the outer surface of the first housing portion 42 and the inner surface of the second housing portion 45. Therefore, the refrigerant L flowing in the first flow path 62 can be in direct contact with the first housing portion 42 that receives the capacitor body portion 51. As a result, the heat transferred from the capacitor element 50 to the refrigerant L flowing in the first flow path 62 can be increased more appropriately. Therefore, the temperature of the capacitor element 50 can be suppressed from becoming too high more appropriately. Therefore, the degradation of the capacitor element 50 can be suppressed more appropriately.

[0078] According to this embodiment, the first housing portion 42 is made of metal. Therefore, compared to the case where the first housing portion 42 is made of resin, the thermal conductivity of the first housing portion 42 can be improved. As a result, the heat transferred from the capacitor element 50 to the refrigerant L flowing in the first flow path 62 can be increased more appropriately. Therefore, the temperature of the capacitor element 50 can be more appropriately suppressed from becoming too high.

[0079] According to this embodiment, the first housing portion 42 is provided with a plurality of protrusions 42c protruding into the interior of the first flow path 62. Therefore, as described above, the contact area between the refrigerant L flowing in the first flow path 62 and the first housing portion 42 can be increased. As a result, the heat transferred from the capacitor element 50 to the refrigerant L flowing in the first flow path 62 can be increased more appropriately. Therefore, the temperature of the capacitor element 50 can be more appropriately suppressed from becoming too high.

[0080] According to this embodiment, the second housing portion 45 is made of resin and is formed by inserting the first housing portion 42 as an insert member. Therefore, the housing portion 41 is easy to manufacture, thus reducing the increase in manufacturing time and cost of the capacitor module 40.

[0081] The busbar module 30 has a plurality of busbars 33 and a first retaining member 31 made of resin that holds the plurality of busbars 33. The first retaining member 31 is formed by inserting the plurality of busbars 33 as embedded members. Therefore, the busbar module 30 can be easily manufactured, thereby suppressing the increase in manufacturing time and manufacturing cost of the busbar module 30.

[0082] The multiple busbars 33 include a first busbar 34 and a second busbar 35 through which approximately equal currents flow in opposite directions. In this embodiment, by arranging a portion of an insulating first holding member 31 between the first busbar 34 and the second busbar 35, they can be easily arranged close together. Therefore, the mutual inductance generated by the current flowing in the first busbar 34 and the current flowing in the second busbar 35 acts in a manner that cancels out self-inductance, reducing the parasitic inductance generated in each busbar 33. As a result, the increase in surge noise caused by the switching operation of the power semiconductor element 24c of the power module 24 can be suppressed. Therefore, the large size of the noise filter provided to remove noise generated in the power module 24 can be suppressed. As a result, the large size of the power conversion device 10 can be suppressed, and the increase in the manufacturing cost of the power conversion device 10 can be suppressed.

[0083] According to this embodiment, the first connecting terminal 52 and the busbar 33 are fixed by welding. Therefore, compared with the case where the first connecting terminal 52 and the busbar 33 are fixed by fastening members such as bolts, there is no need to allocate space for fastening members. Therefore, it is easy to prevent the capacitor module 40 and the busbar module 30 from becoming larger. Therefore, it is possible to more appropriately prevent the power conversion device 10 from becoming larger.

[0084] Furthermore, in this embodiment, compared to the case where the first connecting terminal 52 is fixed to the busbar 33 by fastening members such as bolts, there is no need to measure the tightening torque of the fastening members in the manufacturing process of the power conversion device 10. Therefore, the increase in manufacturing time of the power conversion device 10 can be more appropriately suppressed.

[0085] Furthermore, when the first connecting terminal 52 and the busbar 33 are fixed by a fastening member, if the tightening torque of the fastening member is too small, the contact resistance between the first connecting terminal 52 and the busbar 33 will increase. Consequently, the heat generated at the connection between the first connecting terminal 52 and the busbar 33 will increase. In contrast, in this embodiment, as described above, the first connecting terminal 52 and the busbar 33 are fixed by welding, thus easily suppressing the increase in contact resistance between the first connecting terminal 52 and the busbar 33. Therefore, the increase in heat generated at the connection between the first connecting terminal 52 and the busbar 33 can be suppressed.

[0086] According to this embodiment, the power conversion device 10 includes a holding portion 21 for holding the power module 24, and a second flow path 65 for the refrigerant L to flow through the holding portion 21. Therefore, compared to the case where the second flow path 65 is provided in a different component than the holding portion 21, the thermal resistance between the power module 24 and the second flow path 65 can be reduced. As a result, the heat transferred from the power module 24 to the refrigerant L flowing in the second flow path 65 can be increased. Therefore, it is possible to prevent the temperature of the power module 24 from becoming too high.

[0087] Furthermore, in this embodiment, since the second flow path 65 is provided in the holding portion 21, the shape and structure of the housing 11 can be simplified more appropriately compared to the case where the second flow path 65 is provided in the housing 11. Therefore, the increase in manufacturing cost of the housing 11 can be more appropriately suppressed. Consequently, the increase in manufacturing cost of the power conversion device 10 can be more appropriately suppressed.

[0088] <Second Implementation>

[0089] In the following explanation, in Figure 5 The first direction D1 is shown in the figure. In this embodiment, the first direction D1 is the left-right direction of the power conversion device 210. In the following description, the side in which the arrow of the first direction D1 points (+D1 side) is referred to as "the side of the first direction D1" or "the left side". The side opposite to the side in which the arrow of the first direction D1 points (-D1 side) is referred to as "the other side of the first direction D1" or "the right side".

[0090] In the following explanation, in Figure 5 The second direction D2 is shown. In this embodiment, the second direction D2 is the vertical direction of the power conversion device 210. The second direction D2 intersects the first direction D1. In this embodiment, the second direction D2 is orthogonal to the first direction D1. In the following description, the side in which the arrow of the second direction D2 points (the +D2 side) is referred to as the "upper side". The side opposite to the side in which the arrow of the second direction D2 points (the -D2 side) is referred to as the "lower side".

[0091] In the following description, the third direction D3 is appropriately shown in each figure. The third direction D3, as in the first embodiment described above, is the front-rear direction of the power conversion device 210. It should be noted that the terms "upper side," "lower side," "left side," "right side," "front side," and "rear side" are merely names used to describe the relative positional relationships of each part, and the actual configuration relationships may be other than those indicated by these names.

[0092] Figure 5 This is a cross-sectional view showing a portion of the power conversion device 210 in the motor module 290 of this embodiment. The power conversion device 210 includes a housing 11 (not shown), a holding part 221, a pair of power modules 24, a pair of control boards 25, a busbar module 230, a capacitor module 240, and a refrigerant flow path 260. In the following description, the same reference numerals are used to denote the constituent elements that are the same as those in the first embodiment described above, and their descriptions are omitted.

[0093] The retaining part 221 holds the power modules 24. In the second direction D2, the retaining part 221 is disposed between a pair of power modules 24. The power modules 24 are fixed at the upper and lower ends of the retaining part 221. The retaining part 221 has a retaining housing 222 and a pair of heat sinks 23.

[0094] Although the illustration is omitted, the retaining housing 222 is a generally cuboid shape extending along a third direction D3. Two faces of the retaining housing 222 face the first direction D1, and the other two faces face the second direction D2. The retaining housing 222 is provided with a first recess 222a, a second recess 22b, a third hole 22c, and a fourth hole 22d.

[0095] The first recess 222a is recessed downward from the upward-facing (+D2 side) surface of the retaining housing 222. Although not shown in the figure, the first recess 222a is generally rectangular when viewed from the first direction D1. In this embodiment, the first recess 222a opens downward (-D2 side). The second recess 22b is recessed downward from the upward-facing surface of the retaining housing 222. The second recess 222b is recessed upward from the downward-facing surface of the retaining housing 222. Although not shown in the figure, when viewed from the first direction D1, the second recesses 22b and 222b are generally quadrilateral rings with their long sides extending along the third direction D3. The second recesses 22b and 222b surround the first recess 222a from the outer sides of both the second direction D2 and the third direction D3.

[0096] A pair of heat sinks 23 respectively transfer the heat generated in the power module 24 to the refrigerant L flowing in the second flow path 265. One heat sink 223a is positioned above the retaining housing 222 (+D2 side). The other heat sink 223b is positioned below the retaining housing 222 (-D2 side). With the plane orthogonal to the second direction D2 and passing through the plane between the pair of heat sinks 223a and 223b as the plane of symmetry, the shapes of each heat sink 223a and 223b are mutually symmetrical.

[0097] A fixing portion 23b of one heat sink 223a is disposed inside the second recess 22b and fixed to the inner surface of the second recess 22b. A fixing portion 23b of the other heat sink 223b is disposed inside the second recess 222b and fixed to the inner surface of the second recess 222b. Thus, a pair of heat sinks 23 are fixed to the retaining housing 222.

[0098] Each fin portion 23c of one radiator 223a protrudes downward from the main body portion 23a (-D2 side). Each fin portion 23c of the other radiator 223b protrudes upward from the main body portion 23a (+D2 side). Each fin portion 23c is disposed inside the first recess 222a.

[0099] The holding portion 221 is provided with a second flow path 265 for the refrigerant L to flow. In this embodiment, the second flow path 265 is composed of the inner surface of the first recess 222a, the downward-facing surface of the main body portion 23a of one radiator 223a, the upward-facing surface of the main body portion 23a of another radiator 223b, and the outer surface of each fin portion 23c. Each fin portion 23c is in contact with the refrigerant L flowing in the second flow path 265. Other configurations of the holding portion 221 in this embodiment are the same as those in the holding portion 21 of the first embodiment described above.

[0100] A pair of power modules 24 generate currents of a predetermined waveform based on current supplied by an external power source (not shown), and supply this current to the motor 91. Each power module 24 has a power semiconductor element 24c and a second connection terminal 26. The configurations of the power semiconductor element 24c and the second connection terminal 26 in this embodiment are the same as those in the first embodiment described above.

[0101] The second connection terminal 26 electrically connects the power semiconductor element 24c disposed inside the power module 24 to the busbar module 30. Although not shown in the figure, one power module 224a has six second connection terminals 226a. The six second connection terminals 226a include three second positive terminals 26a and three second negative terminals 26b. Another power module 224b has six second connection terminals 226b. The six second connection terminals 226b include three second positive terminals 26a and three second negative terminals 26b. Each second positive terminal 26a is electrically connected to a different pair of power semiconductor elements 24c. Each second negative terminal 26b is electrically connected to a different pair of power semiconductor elements 24c. Thus, current is supplied from the busbar module 230 to each pair of power semiconductor elements 24c via the second connection terminals 26. Other configurations of the power module 24 are the same as those of the power module 24 in the first embodiment described above.

[0102] A control board 225a driving a power module 224a is positioned above a heat sink 223a (+D2 side). Another control board 225b driving another power module 224b is positioned below the other heat sink 223b (-D2 side). A connecting pin 24d electrically connects one power module 224a to one control board 225a. Thus, each power semiconductor element 24c of one power module 224a is electrically connected to one control board 225a. Furthermore, the connecting pin 24d electrically connects another power module 224b to another control board 225b. Thus, each power semiconductor element 24c of another power module 224b is electrically connected to another control board 225b. Each control board 25 controls the power conversion of each power module 24 by applying control pulses to each power semiconductor element 24c.

[0103] like Figure 3 As shown, in this embodiment, the busbar module 230 is positioned to the right (-D1 side) of the power specific module 24 and to the left (+D1 side) of the capacitor specific module 40. The busbar module 230 has a first holding member 231 and a plurality of busbars 233.

[0104] Although not shown in the diagram, the first retaining member 231 is generally cuboid in shape, extending along a third direction D3. Two faces of the first retaining member 231 face the first direction D1, and the other two faces face the second direction D2. In this embodiment, the first retaining member 231 is made of resin and has insulating properties. In this embodiment, the first retaining member 231 is formed by embedding multiple busbars 233 as embedded members. Thus, the first retaining member 231 retains each busbar 233. A first through hole 231a is provided in the first retaining member 231.

[0105] The first through hole 231a is a hole that passes through the first retaining member 231 in the first direction D1. In this embodiment, the first retaining member 231 is provided with three first through holes 231a. Although not shown in the figure, each first through hole 231a is provided at intervals along the third direction D3.

[0106] Multiple busbars 233 electrically connect the power module 24 to the capacitor module 240. Each busbar 233 is a plate-shaped component. The multiple busbars 233 include a first busbar 234 and a second busbar 235.

[0107] The first busbar 234 has a first main body portion 234a and a first protrusion 234h. The first main body portion 234a is held by a first retaining member 231. The first main body portion 234a is a plate-shaped member. Although not shown in the figure, the front end (+D3 side) of the first main body portion 234a is located in a position further forward than the second connecting terminal 26 located at the farthest side. The rear end (-D3 side) of the first main body portion 234a is located in a position further rearward than the second connecting terminal 26 located at the farthest side. The first main body portion 234a has a first portion 234b, a second portion 234c, and a third portion 234d.

[0108] The first part 234b and the second part 234c are plate-shaped structures protruding in the first direction D1. The plate surfaces of both parts face the second direction D2. The left side (+D1 side) of the first part 234b is fixed to the second negative terminals 26b of a power module 224a by bolts 82. The left side (+D1 side) of the second part 234c is fixed to the second negative terminals 26b of another power module 224b by bolts 82. Thus, the first busbar 234 is electrically connected to a pair of power modules 24.

[0109] The third part 234d is a plate extending along the second direction D2. The plate surface of the third part 234d faces the first direction D1. The upper end of the third part 234d is connected to the right end (-D1 side) of the first part 234b. The lower end of the third part 234d is connected to the right end of the second part 234c. A first hole 234e and a second hole 234f are provided in the third part 234d.

[0110] The first hole 234e and the second hole 234f are holes that penetrate the third portion 234d in the first direction D1. When viewed from the third direction D3, the first hole 234e is located above the second hole 234f (on the +D2 side). In this embodiment, there are three first holes 234e. Each first hole 234e is spaced apart from the others in the third direction D3. In this embodiment, there are three second holes 234f. Each second hole 234f is spaced apart from the others in the third direction D3.

[0111] The first protrusion 234h is a plate-shaped portion protruding to the left (+D1 side) from the third portion 234d. The plate surface of the first protrusion 234h faces the second direction D2. Although not shown in the figure, the first busbar 234 has three first protrusions 234h. Each first protrusion 234h is arranged at intervals along the third direction D3. Other configurations of the first busbar 234 are the same as those of the first busbar 34 in the first embodiment described above.

[0112] The second busbar 235 has a second main body portion 235a and a second protrusion 235h. The second main body portion 235a is held in place by the first retaining member 231. The second main body portion 235a is a plate-shaped member. Although not shown in the figure, the front end (+D3 side) of the second main body portion 235a is located further forward than the second connecting terminal 26 located at the farthest side. The rear end (-D3 side) of the second main body portion 235a is located further rearward than the second connecting terminal 26 located at the farthest side. The second main body portion 235a has a fourth portion 235b, a fifth portion 235c, and a sixth portion 235d.

[0113] The fourth part 235b and the fifth part 235c are plate-shaped protrusions in the first direction D1. The plate surfaces of both the fourth part 235b and the fifth part 235c face the second direction D2. The left side (+D1 side) of the fourth part 235b is fixed to the second positive terminals 26a of one power module 224a by bolts 82. The left side (+D1 side) of the fifth part 235c is fixed to the second positive terminals 26a of another power module 224b by bolts 82. Thus, the second busbar 235 is electrically connected to a pair of power modules 24.

[0114] The sixth part 235d is a plate extending along the second direction D2. The plate surface of the sixth part 235d faces the first direction D1. The upper end of the sixth part 235d is connected to the right end (-D1 side) of the fourth part 235b. The lower end of the sixth part 235d is connected to the right end of the fifth part 235c. A third hole 235e and a fourth hole 235f are provided in the sixth part 235d.

[0115] The third hole 235e and the fourth hole 235f are holes that penetrate the sixth portion 235d in the first direction D1. When viewed from the third direction D3, the third hole 235e is located above the fourth hole 235f (on the +D2 side). In this embodiment, there are three third holes 235e. Each third hole 235e is spaced apart from the others in the third direction D3. In this embodiment, there are three fourth holes 235f. Each fourth hole 235f is spaced apart from the others in the third direction D3. When viewed from the first direction D1, a portion of the third hole 235e overlaps with a portion of the first hole 234e. When viewed from the first direction D1, a portion of the fourth hole 235f overlaps with a portion of the second hole 234f.

[0116] The second protrusion 235h is a plate-shaped portion protruding to the left (+D1 side) from the sixth portion 235d. The plate surface of the second protrusion 235h faces the second direction D2. Although not shown in the figure, the second busbar 235 has three second protrusions 235h. Each second protrusion 235h is arranged at intervals along the third direction D3. Other configurations of the second busbar 235 in this embodiment are the same as those of the second busbar 35 in the first embodiment described above.

[0117] In this embodiment, the capacitor module 240 is positioned to the right (-D1 side) of the busbar module 230. The capacitor module 240 has a housing portion 41 and a capacitor element 50. When viewed from the front (+D3 side), the capacitor module 240 of this embodiment is positioned in the state after rotating 90° counterclockwise around the axis extending along the third direction D3 of the capacitor module 40 of the first embodiment. Therefore, the first receiving portion 42a is recessed from the left-facing side (+D1 side) of the first housing portion 42 to the right-facing side (-D1 side) of the first direction D1. Each protrusion 42c protrudes into the interior of the first flow path 62. The second receiving portion 45a is recessed from the left-facing side of the second housing portion 45 to the right-facing side. The first flow path 62 is formed by the outer surface of the first housing portion 42 and the inner surface of the second receiving portion 45a. Other configurations of the housing portion 41 are the same as those of the housing portion 41 of the first embodiment described above.

[0118] Each capacitor body portion 51 is housed within a distinct first receiving portion 42a. A first connection terminal 52 extends from the capacitor body portion 51 to the left, i.e., to the side in the first direction D1 (+D1 side). The two first connection terminals 52 include a first positive terminal 52a and a first negative terminal 52b.

[0119] Each capacitor element 50's first positive terminal 52a passes through a distinct first through-hole 231a in the first direction D1. Each first positive terminal 52a also passes through a first hole 234e of the first busbar 234 and a third hole 235e of the second busbar 235 in the first direction D1, and is fixed to a distinct second protrusion 235h of the second busbar 235. Thus, each capacitor element 50 is electrically connected to the second busbar 235. Each capacitor element 50's first negative terminal 52b passes through a distinct first through-hole 231a in the first direction D1. Each first positive terminal 52a passes through a second hole 234f of the first busbar 234 and a fourth hole 235f of the second busbar 235 in the first direction D1, and is fixed to a distinct first protrusion 234h of the first busbar 234. Thus, each capacitor element 50 is electrically connected to the first busbar 234. Therefore, busbar 233 electrically connects the first connection terminal 52 and the second connection terminal 26. It should be noted that in this embodiment, the first connection terminal 52 and busbar 233 are fixed by welding. Other configurations of the capacitor module 240 in this embodiment are the same as those of the capacitor module 40 in the first embodiment described above.

[0120] In this embodiment, the refrigerant flow path 260 is a flow path that supplies refrigerant L to the first flow path 62 and the second flow path 265. The refrigerant flow path 260 includes a first conduit 61 (see reference 62). Figure 4 ), the first flow path 62, the second pipeline 63 (refer to Figure 4 ), third pipeline 64 (refer to) Figure 4 ), second flow path 265 and fourth pipe 66 (refer to Figure 4 ).

[0121] Second Path 265 Figure 4 The third pipe 64 shown is connected to the fourth pipe 66. Although not shown in the figure, in the second flow path 265, the refrigerant L flows from the rear side (-D3 side) to the front side (+D3 side). As described above, the plurality of fin portions 23c of the pair of radiators 23 are in contact with the refrigerant L flowing in the second flow path 265. As a result, the contact area between the refrigerant L flowing in the second flow path 265 and the pair of radiators 23 can be increased. Other configurations of the refrigerant flow path 260 in this embodiment are the same as those of the refrigerant flow path 60 in the first embodiment described above.

[0122] According to this embodiment, the capacitor element 50 has a capacitor body portion 51 and a first connection terminal 52 extending from the capacitor body portion 51 to the left, i.e., one side in the first direction (+D1 side). The housing portion 41 has a first receiving portion 42a recessed from the left to the right, i.e., the other side in the first direction D1 (-D1 side), to accommodate the capacitor body portion 51, and a first flow path 62 for the refrigerant L to flow. Therefore, compared to the case where the first flow path 62 is provided in a different component than the housing portion 41, the thermal resistance between the capacitor element 50 and the first flow path 62 can be reduced. As a result, the heat transferred from the capacitor element 50 to the refrigerant L flowing in the first flow path 62 can be increased. Therefore, the temperature of the capacitor element 50 can be prevented from becoming too high. Therefore, the degradation of the capacitor element 50 can be prevented.

[0123] Furthermore, in this embodiment, compared to a configuration where a first flow path 62 is provided in the outer casing 11, the shape of the outer casing 11 can be simplified. This helps to reduce the increase in manufacturing costs of the outer casing 11.

[0124] According to this embodiment, the power conversion device 210 includes a holding portion 221 for holding the power module 24, and a second flow path 265 for refrigerant L to flow through the holding portion 221. Therefore, compared to the case where the second flow path 265 is provided in a different component than the holding portion 221, the thermal resistance between the power module 24 and the second flow path 265 can be reduced. As a result, the heat transferred from the power module 24 to the refrigerant L flowing in the second flow path 265 can be increased. Therefore, it is possible to prevent the temperature of the power module 24 from becoming too high.

[0125] Furthermore, in this embodiment, since the second flow path 265 is provided in the holding portion 221, the shape and structure of the housing 11 can be simplified more appropriately compared to the case where the second flow path 265 is provided in the housing 11. As a result, the increase in manufacturing cost of the housing 11 can be more appropriately suppressed.

[0126] The present invention is not limited to the embodiments described above. Other configurations and methods can also be adopted within the scope of the technical concept of the present invention.

[0127] For example, power modules or power semiconductor elements can be in direct contact with the refrigerant without a heat sink, provided insulation can be ensured. In this case, the heat transferred from the power semiconductor element to the refrigerant can be further increased.

[0128] The application of the power conversion device in this embodiment is not limited to generating current for a motor driving a vehicle; it can also generate current for a drive device such as a motor mounted on an electrical appliance. Furthermore, the power conversion device can be an inverter that generates an alternating current of a predetermined waveform from a direct current supplied from an external power source, or a converter that generates a direct current from an alternating current supplied from an external power source.

[0129] The embodiments of the present invention have been described above. However, the various components and combinations thereof in the embodiments are merely examples, and additions, omissions, substitutions, and other modifications to the components can be made without departing from the spirit of the present invention. Furthermore, the present invention is not limited to the embodiments.

[0130] It should be noted that the present technology can be configured as follows. (1) A power conversion device comprising: a capacitor module having a capacitor element and a housing portion for accommodating the capacitor element; a power module having a power semiconductor element for power conversion; a control board for driving the power module; and a busbar module having a busbar, wherein the capacitor element has a capacitor body portion and a first connection terminal extending from the capacitor body portion to one side in a first direction, the power module has a second connection terminal, the busbar electrically connecting the first connection terminal and the second connection terminal, and the housing portion having: a first receiving portion recessed from one side in the first direction to the other side in the first direction for accommodating the capacitor body portion; and a first flow path for refrigerant flow. (2) The power conversion device according to (1), wherein the housing portion has a first housing portion for the first receiving portion and a second housing portion for accommodating the first housing portion, and the first flow path is formed by the outer surface of the first housing portion and the inner surface of the second housing portion. (3) The power conversion device according to (2), wherein the first housing portion is made of metal. (4) The power conversion device according to (2) or (3), wherein a plurality of protrusions protruding into the interior of the first flow path are provided in the first housing portion. (5) The power conversion device according to any one of (2) to (4), wherein the second housing portion is made of resin and is formed by embedding the first housing portion as an embedding member. (6) The power conversion device according to any one of (1) to (5), wherein the busbar module has a plurality of said busbars and a first resin retaining member for retaining the plurality of said busbars, the first retaining member being formed by embedding the plurality of said busbars as an embedding member. (7) The power conversion device according to any one of (1) to (6), wherein the first connecting terminal and the busbar are fixed by welding. (8) The power conversion device according to any one of (1) to (7), wherein the power conversion device includes a retaining portion for retaining the power module, wherein a second flow path for refrigerant flow is provided in the retaining portion. (9) A motor module comprising: a power conversion device according to any one of (1) to (8); and a motor driven by current supplied from the power conversion device.

[0131] Explanation of reference numerals in the attached figures

[0132] 10, 210: Power conversion device; 21, 221: Holding part; 22: Holding housing; 23: Heat sink; 24: Power module; 25: Control board; 24c: Power semiconductor element; 26: Second connection terminal; 30, 230: Busbar module; 31, 231: First holding member; 33, 233: Busbar; 40, 240: Capacitor module; 41: Housing part; 42: First housing part; 42a: First receiving part; 42c: Protrusion; 45: Second housing part; 45a: Second receiving part; 50: Capacitor element; 51: Capacitor body part; 52: First connection terminal; 62: First flow path; 65, 265: Second flow path; 90: Motor module; 91: Motor; D1: First direction; L: Refrigerant.

Claims

1. A power conversion device, comprising: A capacitor module having capacitor elements and a housing portion for accommodating said capacitor elements; A power module, which has power semiconductor elements for power conversion; The control board drives the power module; as well as Busbar module, which has busbars, The capacitor element has a capacitor body portion and a first connection terminal extending from the capacitor body portion in a first direction. The power module has a second connection terminal. The busbar electrically connects the first connection terminal and the second connection terminal. The housing portion has: The first receiving portion is recessed from one side of the first direction to the other side of the first direction to receive the capacitor body portion; as well as The first flow path supplies the refrigerant.

2. The power conversion device according to claim 1, wherein, The housing portion has a first housing portion for receiving the first housing portion and a second housing portion for receiving the first housing portion. The first flow path is formed by the outer surface of the first housing portion and the inner surface of the second housing portion.

3. The power conversion device according to claim 2, wherein, The first housing part is made of metal.

4. The power conversion device according to claim 2, wherein, The first housing portion is provided with a plurality of protrusions that protrude into the interior of the first flow path.

5. The power conversion device according to claim 2, wherein, The second housing part is made of resin and is formed by inserting the first housing part as an insert member.

6. The power conversion device according to claim 1, wherein, The busbar module has a plurality of busbars and a first resin retaining member for retaining the plurality of busbars. The first retaining member is formed by embedding the plurality of said busbars as embedded members.

7. The power conversion device according to claim 1, wherein, The first connecting terminal and the bus bar are fixed together by welding.

8. The power conversion device according to claim 1, wherein, The power conversion device includes a holding part for holding the power module. The retaining part is provided with a second flow path for the refrigerant to flow.

9. A motor module, comprising: The power conversion device according to any one of claims 1 to 8; and The motor is driven by current supplied from the power conversion device.

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